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Article

Cucurbita pepo var. styriaca Seeds: Deep Insights into Polar Lipid Profile

by
Annunziata Paolillo
1,2,
Assunta Napolitano
1,*,
Francesco Sottile
3,
Milena Masullo
1 and
Sonia Piacente
1,4,*
1
Dipartimento di Farmacia, Università degli Studi di Salerno, Via Giovanni Paolo II n. 132, 84084 Fisciano, SA, Italy
2
PhD Program in Drug Discovery and Development, Università degli Studi di Salerno, Via Giovanni Paolo II n. 132, 84084 Fisciano, SA, Italy
3
Dipartimento di Architettura, Università degli Studi di Palermo, Piazza Marina 61, 90133 Palermo, PA, Italy
4
National Biodiversity Future Center (NBFC), 90133 Palermo, PA, Italy
*
Authors to whom correspondence should be addressed.
Foods 2026, 15(12), 2215; https://doi.org/10.3390/foods15122215
Submission received: 6 May 2026 / Revised: 9 June 2026 / Accepted: 16 June 2026 / Published: 19 June 2026
(This article belongs to the Special Issue Plant-Based Lipids for Metabolic Health)
Browse Figures
Versions Notes

Abstract

The edible seeds of pumpkin plants (genus Cucurbita) are becoming increasingly appreciated as functional foods for their nutritional benefits, medicinal properties, and bioactive compounds, including lipids, proteins, and antioxidants. Particularly, the naked seeds of Cucurbita pepo var. styriaca have proved to yield both an edible oil showing anti-inflammatory properties in treating skin disorders and hydro-alcoholic extracts effective in inhibiting the growth of cancer cells. In this study, a detailed and extensive analysis of the eco-friendly alcoholic extract of the seeds of this variety was accomplished by using LC-HRMSMS techniques, with the main aim to broaden the knowledge on bioactive lipids other than the already reported fatty acids. The obtained results highlighted the occurrence of numerous compounds belonging to different classes of polar and neutral lipids, such as phospholipids, sphingolipids, glycolipids, acylglycerols, and oxylipins. Noteworthily, a significant presence of Cer-(EO)LCBs, i.e., Cer-EOS-type ceramides with different long chain base (LCB) and fatty acid composition, was detected, representing a real novelty for pumpkin. Additionally, a good number of multiflorane-type triterpenoids were detected, only some of which were previously reported in this plant. These findings highlight the nutraceutical value of these edible seeds.

Graphical Abstract

1. Introduction

Since the early times of humanity, pumpkin plants, belonging to the genus Cucurbita (Cucurbitaceae family), have been cultivated as a major crop grown in tropical and temperate regions for their economic importance due to their nutritional value. They have also been used worldwide in traditional medicine for their anti-inflammatory, antioxidant, antiviral, and anti-diabetic properties [1,2].
Along with the pulp, the peel and seeds can be utilized for food purposes. In particular, pumpkin seeds, having a rich nutty flavor and chewy texture, once toasted and salted, are consumed in many countries directly as a snack, salad dressing, or breakfast cereal, served as an ingredient in bread or cakes, or used as additives in bakery industries [1,3]. They are an extraordinarily rich source of lipids (among which unsaturated fatty acids, i.e., UFAs), proteins, carbohydrates, fibers, and some essential micronutrients, as well as of bioactive compounds like phenolics, squalene, phytosterols, tocopherols (α, β, γ and δ), tocotrienols, carotenoids, and flavonoids. According to this, pumpkin seeds are gradually attracting attention in large-scale food, pharmaceutical, and cosmetic applications, changing their status nowadays from waste by-products of agro-industrial processes to super-seeds falling into the category of functional foods that may have the ability to establish a positive relationship between health and diet [1,2,3,4,5,6,7].
In this regard, available literature indicates that total edible oil extracted from pumpkin seeds may exert beneficial effects against benign prostatic hyperplasia (BPH) and could play a potential role in managing metabolic disorders, including diabetes-related conditions [8,9]. Further evidence, largely derived from seed oil fractions or preliminary experimental models, suggests that pumpkin seed oil could be associated with protective effects on cardiovascular health, particularly regarding hypertension and hypercholesterolemia [5,10]. Additionally, when applied topically, total oil extracts have shown potential in supporting skin homeostasis by demonstrating soothing, anti-inflammatory, wound-healing, and photo-protective properties [11,12,13].
A prominent example of these matrices is found in Austria, where the special Styrian pumpkin variety (Cucurbita pepo var. styriaca), characterized by ‘naked’ or hull-less seeds, has been cultivated for decades. The conditioned, green-colored oil obtained from its seeds is particularly renowned for its unique sensory and optical characteristics, such as a nutty aroma and a distinct dark-green color [9,14,15]. Recent studies investigating this total oil suggest potential anti-inflammatory properties upon topical application, exploring its possible use in the management of mild to moderate skin inflammation, including acne-related conditions [14,16,17]. Beyond the oil, eco-friendly hydro-alcoholic extracts of pumpkin seeds have also been investigated for their potential biological activities. Specifically, in vitro antiproliferative effects against prostate, breast, and colon cancer cell lines, as well as regulatory effects on hyperplastic cell models, have been reported, providing partial support for the traditional use of pumpkin seeds as a complementary approach in BPH management [18].
From a chemical-analytical point of view, the most studied lipid class for Styrian pumpkin seeds is represented by free fatty acids, with the predominance of essential fatty acids (FA) like linoleic ω-6 (LA or FA 18:2 n-6) and oleic ω-9 (OA or FA 18:1 n-9) with respect to palmitic (PA or FA 16:0) and α-linolenic ω-3 (ALA or FA 18:3 n-3) [9,14,15]. Limited research is currently available on other lipid classes, particularly polar lipids such as phospholipids (PLs), glycolipids (GLs), and sphingolipids (SLs). Beyond simply carrying essential fatty acids, polar lipids are fundamental to cell membrane integrity, cell signaling, regulation of inflammation, and skin barrier function. There is growing scientific interest in these lipids due to their nutritional importance and bioactivities, which include antioxidant, anti-inflammatory, antitumoral, immunomodulatory, and antimicrobial properties [19,20,21,22,23,24,25,26,27]. Thereby, analyzing these lipids could reveal functional health benefits of Cucurbita pepo var. styriaca, moving past standard fatty acid profiles. On the other hand, the technological advances in chromatography and mass spectrometry platforms allowed the establishment of analytical methods able to characterize a wide range of intact lipid molecules occurring in complex samples. Mass spectrometry-based lipidomics has recently advanced the structural and compositional characterization of native lipid profiles within the Cucurbitaceae family. For instance, a recent screening of eleven distinct Cucurbita cultivars has utilized an integrated platform combining gas chromatography (GC), GC-mass spectrometry (GC-MS), and ultra-high-performance liquid chromatography (UPLC) to map the baseline distribution of native fatty acids, sterols, triacylglycerols, and diacylglycerols [28]. To achieve deeper structural insights into specific lipid classes, complementary liquid chromatography modes have been successfully coupled with tandem mass spectrometry. Specifically, the orthogonal combination of reversed-phase (RPLC-MS/MS) and hydrophilic interaction liquid chromatography (HILIC-MS) has enabled the comprehensive profiling of polar lipids in Cucurbita maxima oily seeds, resolving over 180 phospholipid molecular species across eight distinct classes [29]. This high-throughput capability has been further exemplified in other Cucurbitaceae species, such as Cucumis melo, where untargeted UHPLC-MS/MS profiling has successfully annotated more than 2500 lipid molecules spanning 7 categories and 47 subclasses, underscoring a prominent structural and storage prevalence of glycerolipids and glycerophospholipids [30].
Therefore, this paper aims at gaining deep insights that can extend the state of the art on the lipid composition of Styrian pumpkin seeds, including, where possible, unusual subclasses, by analyzing its alcoholic extract obtained using environmentally friendly and low-toxicity food-grade ethyl alcohol, by applying a liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-HRMSMS) method. In this way, highly diagnostic fragmentation spectra for each lipid class were generated, allowing us to assign the chemical formula to each product ion as well as to the precursor molecular ions, obtaining key structural information to explore the depth and breadth of lipid chemical diversity.

2. Materials and Methods

2.1. Plant Sample

The seeds of Cucurbita pepo var. styriaca (250 g), obtained from controlled organic cultivation of Styrian pumpkin in Austria, were purchased from Kräuterhaus Sanct Bernhard (Bad Ditzenbach, Germany) in September 2022. Samples were maintained at 4 °C during transport and stored at the same temperature.

2.2. Chemicals

Ethanol (absolute, ≥99.8%) for extraction was purchased from VWR International PBI S.r.l. (Milan, Italy). Acetonitrile (≥99.9%), water, and formic acid (≥99.8%) for LC-MS were purchased from VWR International PBI S.r.l. (Milan, Italy).

2.3. Sample Preparation Procedures

The pumpkin seeds were manually crushed. The entire procedure was performed using independent extraction replicates (n = 3). An amount of 5 g per replicate was immediately submitted to extraction by maceration with ethanol at room temperature and protected from light (50 mL × 3 days × 3 times, i.e., until the yield of the last extraction was <10%). In order to remove the non-extractable residue, each ethanolic extract was filtered through paper and concentrated under vacuum using a rotary evaporator. The method demonstrated high reproducibility, yielding a mean dry crude extract of 630 ± 4 mg, with an average percentage yield of 12.6% ± 0.08%. The resulting independent extracts were stored in air-tight glass vials at 4 °C for three days and subsequently analyzed separately under identical conditions.

2.4. UHPLC-Q-Orbitrap MS/MS Analysis

The ethanolic extracts of the seeds of Cucurbita pepo var. styriaca were analyzed by LC-ESI/HRMS, using a Thermo Ultimate RS 3000 ultrahigh-performance liquid chromatography (UHPLC) system coupled to a Q-Exactive high-resolution mass spectrometer equipped with a hybrid quadrupole-Orbitrap analyzer and HESI II heated electrospray ionization source (Thermo Fisher Scientific, Bremen, Germany), operating in positive and negative ionization modes. In accordance with our laboratory’s well-established chromatographic separation protocols for the analysis of polar lipids [19,23,31,32], separation was performed using a Symmetry 300 C-4 column (RP-4, 3.5 µm, 2.1 mm × 150 mm; Waters, Milford, MA, USA) held at 30 °C. The mobile phase consisted of 0.1% formic acid in water (v/v) as solvent A and 0.1% formic acid in acetonitrile (v/v) as solvent B, operating with a linear gradient from 30% to 95% B over 12 min, from 53% to 62% B over 9 min, from 62 to 95% B over 17 min, held at 95% B over 4 min, a flow rate of 0.2 mL/min. The autosampler was set to inject 8 μL of each ethanolic extract (0.5 mg/mL) in triplicate. In order to optimize analysis in both ionization modes, samples were run in separate batches for positive and negative polarities with dedicated HESI source parameters. Specifically, the spray voltage was set to 3.5 kV for positive mode and reduced to 2.5 kV for negative mode to prevent corona discharge. Capillary and probe heater temperatures, along with gas flows, were tailored independently for each batch to maximize desolvation efficiency based on polarity. The final parameters were capillary temperature 320 °C (positive) and 300 °C (negative); sheath gas 50 arbitrary units (a.u.); auxiliary gas 12.50 a.u. (positive) and 10 a.u. (negative); probe heater temperature 300 °C; and S-lens radio frequency (RF) voltage 50 a.u. The MS spectra were acquired in a mass range m/z 150–1400 with a resolution power of 70,000. To obtain HRMS/MS spectra, a “data dependent scan” experiment was performed, in which the first five intense ions in the HRMS spectrum were selected to be subjected to fragmentation, using a normalized collision energy (NCE) of 30 and a resolving power of 17,500. Xcalibur software (version 2.2) was used for instrument control, data acquisition, and data analysis. Metabolite identification was carried out through a manual comparative analysis of accurate precursor masses and MS/MS fragmentation pathways against peer-reviewed scientific literature. To validate the reliability of the qualitative profiling, the compounds were successfully annotated and included in the corresponding Table only if their specific mass spectrometric features and literature-matched criteria were consistently confirmed in all three independent extraction replicates. The validation thresholds were set as follows: an accurate mass error of <5 ppm for precursor ions and the presence of key diagnostic product ions matching literature-reported fragmentation pathways. System precision was established through outstanding retention time stability, with chromatographic behavior showing negligible variation (RSD < 1%) across all injections.

3. Results and Discussion

3.1. LC-HRMS/MS Analysis of the Styrian Pumpkin Seeds

In order to study the polar lipids of C. pepo var. styriaca seeds, ethanol was chosen as a safe, eco-friendly solvent, offering a sustainable alternative to toxic chloroform/methanol solvents. Although considered less effective in recovering highly hydrophobic lipids (such as neutral lipids and triacylglycerols), ethanol still extracted them efficiently enough for the study while offering a lower environmental impact. Additionally, ethanol’s high polarity served as a major advantage, effectively capturing highly interesting polar lipid classes, as highlighted by the LC-HRMS/MS analysis. This latter was carried out by using a UHPLC-Q-Exactive system in consideration of its sensitivity, high resolution, high mass accuracy, powerful product ion scanning capability, and ability to give in-depth lipid profile information, operating by both negative and positive electrospray ionizations, in consideration of the different structures and polarities of the lipid classes. Moreover, in order to reduce the strong interactions between the stationary phase and the hydrocarbon skeleton of higher molecular weight lipids, a RP-C4 column instead of a RP-C18 was used, allowing the shortening of retention time of less polar lipid classes, e.g., sphingolipids, and the complete separation of all polar lipid classes in a single chromatographic run. By studying the chromatographic behavior, accurate mass, and fragmentation pattern of each detected ion peak, and by comparing the acquired analytical data with those occurring in the literature, the molecular pool of the Styrian pumpkin variety could be defined as composed of metabolites mainly belonging to five distinct lipid classes, i.e., phospholipids, sphingolipids, glycolipids, oxylipins, and acylglycerols, along with specialized metabolites ascribable to the triterpenoid class (Figure S1).

3.1.1. Phospholipids

The largest group among the compounds detectable in Styrian pumpkin seeds was undoubtedly represented by phospholipids, polar lipids being the main constituents of biological membranes and exerting important structural and functional properties [23,24]. Beyond their roles as structural components of cellular membranes, dietary phospholipids (PLs) possess significant nutritional, functional, and health-promoting relevance. Functionally, they act as natural emulsifiers that modulate lipid digestion and transport, while delivering essential fatty acids and choline directly for cellular signaling and membrane fluidity. Furthermore, evidence highlights their therapeutic potential in mitigating hepatic steatosis, improving cognitive function, and attenuating systemic inflammatory responses [33,34,35]. They are made up of several distinct moieties and different polar head groups; these latter define the different subclasses of phospholipids, in turn consisting of a mixture of many molecular species containing different combinations of fatty acids at the sn-1 and sn-2 positions on the glycerol backbone. The careful analysis of the tandem mass spectra allowed us to assign each compound to the correct PL subclass by giving information on the nature of the headgroup and allowing us to ascertain the main occurrence of phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), and phosphatidylinositols (PIs) (Table 1). Moreover, phospholipids in which only one of the sn-1/sn-2 positions of glycerol is fatty acylated, i.e., the lyso-phospholipids (l-PL), were also detectable, all belonging to the previously mentioned PL subclasses, apart from one representative of the lyso-phosphatidic acid (l-PA) subclass (Table 1). Finally, two compounds assignable as N-acylglycerophosphatidylethanolamines (NA-GPEs), i.e., lipid compounds in which the only fatty acid is involved in an amide linkage with the amino head group of glycerophosphoethanolamine, along with three metabolites having the structure of phosphatidylethanols (PEths), i.e., phospholipids deriving from phosphatidic acids in which an ethyl group is located on the phosphate group [36], were identified (Table 1). As mentioned above, the tandem mass spectrometry technique represents a powerful tool for the lipid study as the fragmentation pathway of the components of each PL subclass allowed to discriminate them, even in the case, e.g., of l-PC/L-PE/NA-GPE and PC/PE, characterized by molecular formulae sharing the same heteroatomic composition (O7NP and O8NP, respectively) but yielding diagnostic product ions via typical neutral losses in tandem mass experiments. So, for example, the detection of a product ion at m/z 184 (C5H15O4NP) in the positive HRMSMS spectrum was promptly indicative of the phosphocholine head group, whereas the occurrence in negative tandem mass spectra of diagnostic product ions at m/z 214 and 196 (C5H13O6NP and C5H11O5NP, respectively) identified l-PE/PEs, corresponding to the glycero-phosphatidylethanolamine ion and to its mono-dehydrated form, respectively (Table 1). Instead, the occurrence in the negative HRMSMS spectrum of a main product ion originated from the [M-H]− ion by neutral loss of the mono-dehydrated-glycerol moiety (74 Da, C3H6O2) and corresponding to the phosphorylated N-fatty amide head group ion, promptly identified the NA-GPEs (Table 1). Moreover, in the case of l-PI/PIs, the structural assignment was guided by the detection in the negative tandem mass spectrum of the diagnostic product ion at m/z 241 (C6H10O8P), corresponding to the dehydrated form of the inositol-phosphate. Finally, the occurrence in the negative HRMSMS spectrum of the product ion at m/z 152 (C3H6O5P), due to the mono-dehydrated glycerophosphate, allowed us to ascertain the presence of l-PA, while the detection of the product ion at m/z 125 (C2H6O4P), corresponding to a 2-hydroxyethyl phosphonate, was indicative of a PEth (Table 1).
Contemporarily, both negative and positive HRMSMS spectra allowed the assignment of the fatty acids composing l-PL/PL, by checking the occurrence of abundant RxCOO− fatty acid ions in the negative ion spectra and of product ions corresponding to the monodehydrated form of the monoacylated-glycerol unit in the positive ion spectra, respectively (Table 1). Moreover, the occurrence in this variety of C. pepo of a good number of l-PL/PL composed of oxidized fatty acids could be appreciated (Table 1). These latter could be assumed to be naturally present in the seeds of Cucurbita pepo var. styriaca, as a result of endogenous oxidative processes, rather than being considered as derived from artificial oxidation occurring during sample handling, extraction, and storage, as these procedures were conducted under controlled conditions for light, temperature, and storage atmosphere.
Comparison of the number of lipids belonging to each detected PLs subclass allowed us to estimate that phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), and phosphatidylinositols (PIs), including their lyso-forms (l-PCs, l-PEs, and l-PIs), were the most represented subclasses in the pumpkin seed extract, with in particular the l-PC/PC subclass accounting for approximately 39% and both l-PE/PE and l-PI/PI for 26% each (Figure S2a). Moreover, it could be appreciated that in each of these three subclasses, the number of detected lyso-type compounds was significantly lower than that of the diacylated type (Figure S2b). It is noteworthy that, among the PLs with the highest peak intensities, PCs accounted for the largest number of species compared to PEs and PIs (Table 1).
By considering the composition in acyl chains of the different types of detected PLs, natural carriers of dietary FAs, a first difference among the main lyso-form subclasses in terms of composition in saturated and unsaturated FAs could be noted. In fact, l-PCs were mainly composed of unsaturated fatty acids, above all FA 18:2, in contrast to l-PEs, mainly made up of saturated FAs as 16:0 and 18:0, and l-PIs, having both the saturated and unsaturated species equally represented and composed of the same FAs so far considered (Figure S2c). Moreover, in the l-PCs were also comprised FAs in the oxygenated form (3, 4, 6), not present in either l-PEs or in l-PIs, which instead included in their subclass a l-PI structure (15) composed of an unsaturated alkyl chain ether-linked rather than ester-linked to the glycerol core, a typology of etherPI described also in other plant seeds (Table 1) [37].
On the other hand, by considering the diacylated PLs, at least one fatty acid of each detected structure was unsaturated, and once again the FA 18:2 was the most represented one, followed by the FA 18:1, and only to a minimal extent by FAs 18:3 and 16:1 (Figure S2d). These results were in agreement with the literature on seed FA composition of the Styrian variety grown in Austria [9,14]. However, these reports considered either FAs released by transmethylation from total lipid classes and analyzed by GC-FID, or FAs composing TGs, rather than FAs occurring in PLs alone.
In any case, PEs resulted in the PLs compounds showing the greatest acylation ratio of unsaturated FAs versus saturated ones, followed by PCs and finally PIs, with the FA 16:0 being the most recurring saturated fatty acid. Furthermore, all the three main PL classes displayed the occurrence of more or less the same number of components in which one fatty acid was oxygenated, mainly being FA 18:2-O1 in PCs, FA 18:2-O2 in PEs and both FA types in PIs, even though PCs with no oxylipin were in higher number than those in which an oxidized acyl chain composed the structure (Table 1; Figure S2d).

3.1.2. Sphingolipids

Among polar lipids occurring in the ethanol extract of Styrian pumpkin seeds, sphingolipids were the second group in terms of the number of components (Figure S1). SLs are an ubiquitous structural lipid class, characterized by a considerable structural variety, occurring in the biological membranes and performing additional essential functions as signaling molecules [21,22,23]. The basic building block of SLs is an amino-alcohol long-chain base (LCB), characterized by the presence of hydroxyl groups at C1 and C3 and an amino group at C2; it can vary on the basis of the length of the chain, commonly being C18, and its degree of hydroxylation and unsaturation. In the positive tandem mass spectra of Styrian pumpkin seed extract, five LCBs (5, 9, 11, 16, 18) could be detected, assigned by considering both their molecular formula and fragmentation pattern, which displayed main product ions generated by neutral loss of water molecules and CH2O moieties, useful to estimate the number of hydroxyl groups present in the sphingoid base (Table 2). Moreover, diagnostic product ions at m/z 106.0866 (C4H12O2N) and m/z 122.0814 (C4H12O3N), corresponding to the protonated forms of 2-aminobutane-1,3-diol and 3-aminobutane-1,2,4-triol, were observed in the positive-ion tandem mass spectra of compounds 9 and 11, respectively. These ions enabled the identification of dihydrosphingosine (d18:0) and phytosphingosine (t18:0), respectively (Table 2). Another dihydroxylated LCB, likely N-acetylsphingosine (d18:1), and two trihydroxylated LCBs, likely dehydrophytosphingosine (t18:1) and C19-dehydrophytosphingosine (t19:1), could be additionally identified by considering, along with the others, the product ion generated by the neutral loss of a C2H4O moiety from the [M + H]+ ion of 16 and corresponding to an acetyl unit, and the product ion at m/z 74.0606 (C3H8ON), occurring in the trihydroxylated LCBs and likely corresponding to a protonated 2-aminopropanal formed by rearrangement of the hydroxyl group at C4 in aldehyde form, contemporary to the cleavage of the C3-C4 bond and neutral loss of a water molecule, respectively (Table 2).
By carefully analyzing both positive and negative tandem mass spectra, the occurrence of metabolites known as ceramides (Cers) could also be highlighted. These compounds are generated by N-acylation of the LCB amine group with fatty acids mainly composed of saturated or not 18 and 16 carbon chains and in some cases characterized by a hydroxyl group (hence FA h, instead of FA N, where N is for “non-hydroxylated”) which in plants is usually located at C-2 (81, 83, 86, 91, 96, 101; Table 2).
Interestingly, at later retention times, a large group of ceramides, showing in their tandem mass spectra product ions that suggested the occurrence of a second fatty acid unit in the structural core, could be detected (117–118, 120, 122, 126, 129, 131–133, 137–155; Table 2). In fact, the analysis of tandem mass spectra of these compounds allowed both the prompt ascertainment of the identity of the LCB groups—by observing the presence of a main product ion generated by neutral loss of the intact sphingoid base from the [M + H]+ ion—and the exclusion of the O-acylation of the second fatty acid on the LCB unit. For example, in the case of compound 149, the occurrence in the tandem mass spectrum of the main product ion at m/z 535.4723, corresponding to the C34H63O4 elemental composition and originating from the neutral loss from the precursor ion of a structural moiety having the C16H33NO2 elemental composition, indicative of a d16:1 long chain base, could be observed. This finding along with the contemporary absence of product ions that could be formed by the removal of an acyl chain from the [M + H]+ ion, allowed to assign the ion at m/z 535.4723 as the dual-acyl core formed by the two fatty acids covalently linked to each other, thereby ruling out alternative structural isomers where the second FA was directly attached to the LCB (Table 2; Figure 1).
At the same time, by considering the elemental composition of this product ion, both the number of double bonds and overall the length of the carbon chain of the fatty acyl portion could be deduced (e.g., in the case of compound 149, it was determined to be C34:1) (Table 2). Moreover, the careful analysis of the positive HRMSMS spectra of these compounds, highlighting the presence of a product ion having three oxygen atoms in its molecular formula, likely generated by the neutral loss of the monodehydrated form of the second fatty acyl chain, allowed to infer that the FA involved in the N-acylation with the LCB group of the ceramide had to be a FA holding an additional hydroxyl group in its structure (Table 2). Specifically, for the case study of compound 149, it could be assumed that the product ion at m/z 299.2587 (C18H35O3) was generated by the cleavage of the ester bond (via neutral loss of a C16H28O moiety) and corresponded to the dihydroxylated form of the octadecanoic acid, i.e., a α-hydroxylated FA (FA h, inner acyl-chain) with an additional hydroxyl group, native to its structure (Table 2; Figure 1). Furthermore, the detection of a minor product ion at m/z 237.2212 (C16H29O) allowed the assignment of the second fatty acid (outer acyl-chain) under the well-stabilized form of a monodehydrated acyl-chain generated during the ester bond cleavage (Table 2; Figure 1). Some literature reports describe the occurrence in seeds of plants such as sesame and Camellia oleifera of a typology of ceramides known as Cer-EOS (Ceramide by Esterification of the Omega-hydroxyl group of fatty acid linked on Sphingosine), i.e., ceramides in which the fatty acid N-acylated to the LCB sphingosine has an ω-hydroxyl group (hence FA O) involved in the esterification of a second fatty acid (hence FA E). Considering this, a similar structural composition for the metabolites identified in Styrian pumpkin seed extract [38,39] could be tentatively suggested. Moreover, the occurrence in the tandem mass spectra of product ions ascribable to consecutive fragmentations involving both fatty acyl chains confirmed this hypothesis (Table 2). These findings are noteworthy considering that this is the first study describing the occurrence of this compound class in pumpkin. It is well-known that a deficiency of ceramides, essential components of the lipid skin barrier, may account, at least in part, for the dysfunction of the skin stratum corneum associated with aging and other inflammatory skin disorders (e.g., atopic dermatitis, psoriasis, ichthyoses). In fact, topical application of ceramide-based formulations as well as dietary ceramide-based supplementations have been proven as treatments able to restore skin-ceramide levels and lipid organization in the stratum corneum, by improving the epidermal barrier functionality in damaged skin, showing positive effects on skin-moisturizing and skin barrier recovery [40,41,42,43,44]. By considering the peculiar structural features of Cer-EOS molecules, it could be postulated that they have a potential structure–activity relationship in determining physical skin-barrier restoration, limiting trans-epidermal water loss. The ultra-long carbon chain, resulting from the mutual esterification of two fatty acids, may allow Cer-EOS molecules to act as a “bridge” between adjacent lipid lamellae in the stratum corneum. This arrangement would promote the organization of lipids into a long-periodicity phase, which is essential for skin impermeability. Furthermore, the presence of unsaturation on the terminal acyl chain could introduce molecular kinks, creating fluid microdomains within an otherwise rigid crystalline matrix. This structural alternation between crystalline and fluid domains may physically prevent water evaporation and shield the skin from external pathogens. Thereby, a potential role for these molecules in the treatment of skin inflammation could be hypothesized, in line with literature evidence ascribing similar anti-inflammatory properties to Styrian pumpkin seed variety, although it must be noted that existing studies investigated the oil matrix [16,17]. Finally, two metabolites belonging to the subclass of hexosylceramides (HexCers), glycosylation products of the primary hydroxyl group of the LCB unit, usually with glucose or galactose, were detectable in HRMSMS spectra of both polarity by observing, along with the product ions generated by fragmentation pathway involving the LCB and the FA moieties, the presence of product ions formed by neutral loss of C6H10O5 and C6H12O6 units, corresponding to the hexose group in the monodehydrated and whole form, respectively (62, 66; Table 2).
Evaluation of the number of species within the different SL structural groups revealed that Cer-(EO)LCB—so named due to their varying LCB composition—was the most represented subclass, both numerically and in terms of peak intensity (Figure S3a; Table 2). In particular, by considering the type and the number of sphingoid bases composing SL structures, undoubtedly Cer-(EO)LCBs showed the highest variability (Figure S3b). Notably, the most occurring LCB was the d16:1, likely a C16-sphingosine, rather than the C18-sphingosine, immediately followed, but to a lesser extent, by the LCB d18:2, likely sphingadienine, and the trihydroxylated LCB t18:2, previously described in the fungus Cordyceps sinensis [25], and the LCB t18:1, likely dehydrophitosphingosine (Figure S3b). Interesting was also the evaluation of the type of FAs N-acylating the sphingoid bases of SLs (Figure S3c). In fact, if Cers showed a predominance of N-type FAs with respect to HexCers, the FAs composing SLs of both subclasses were characterized only by acyl chains with an even number of carbon atoms, in contrast to those belonging to Cer-(EO)LCB subclass, mainly characterized by long acyl chains mostly having an odd number of carbon atoms, being FA O21:2 the most numerous. On the contrary, the E-type FAs were chemically characterized by shorter acyl chains, mostly with an even number of carbon atoms, with FA E16:1 being the most represented along with FA E18:2 (Figure S3d).

3.1.3. Acylglycerols

The third class in order of number of components detected in the ethanolic extract of Styrian pumpkin seeds was that of acylglycerols (AGs) (Figure S1; Table 3), structurally made up of a glycerol core esterified with one to three fatty acids to form mono-, di-, and triacylglycerols (MGs, DGs, and TGs), respectively. In plants, diacylglycerols are intermediates in the biosynthesis of triacylglycerols and other glycerolipids, including many phospholipids and mono- and digalactosyldiacylglycerols, while TGs are important high-energy compounds and a source of structural fatty acids, providing energy and carbon skeletons for seed germination and seedling development [45]. Analogously, triacylglycerols are the main dietary source of energy and essential fatty acids in humans [46]. Their fatty acid composition strongly influences cardiovascular and metabolic health, particularly the balance between saturated and unsaturated fatty acids [47]. Mono- and diacylglycerols are important intermediates in lipid digestion and enhance intestinal absorption of lipids and lipid-soluble vitamins [46]. Diets rich in unsaturated triacylglycerols have been associated with improved lipid profiles and reduced risk of cardiovascular disease [47,48].
The structural features of these lipids were promptly highlighted by observing in the tandem mass spectra acquired in positive ion mode the presence of product ions generated by neutral loss of one or two whole FAs, the first occurring both in diacylglycerols (DGs) and in triacylglycerols (TGs) HRMSMS spectra, the second ones detectable only in fragmentation spectra of TGs (Table 3). In addition to product ions corresponding to the monodehydrated FAs, allowing us to assign their identity by analyzing the HRMSMS spectra of both acylglycerol subclasses, the fragmentation pattern of DGs was also characterized by diagnostic product ions formed from the [M + H]+ ion by neutral loss of a water molecule (Table 3). Moreover, the neutral loss of two FA units in TGs allowed the detection of product ions corresponding to the didehydrated form of the monoacylated glycerol core (Table 3). Interestingly, the mass spectrometric data allowed to identify in Styrian pumpkin seed extract the occurrence of two metabolites belonging to a third subclass, namely monoacylglycerol ethers (MGEs), characterized by a different form of functionalization of the glycerol core in which an alkyl substituent is ether-bound at one glycerol oxygen and an acyl substituent is O-esterified at another glycerol position, with usually the location of etherification being at sn-1-position, and the O-acylation occurring at the sn-2-position. This type of naturally occurring lipid is considered a functional lipid with well-recognized health benefits, showing a positive correlation between dietary intake and treatment and prevention of several diseases, including obesity, diabetes, inflammation, and cancer [37,49]. The analysis of tandem mass spectra showed the product ion corresponding to the monodehydrated acylic portion, along with the product ion corresponding to the protonated alcohol involved in the ether-linkage with the glycerol unit. These data, along with the molecular formula ascribable to these lipid compounds, displaying four oxygen atoms instead of five, as in the case of DGs, supported this structural hypothesis (87, 93; Table 3). Among the three acylglycerol subclasses, MGE was the least represented, while the TG subclass was the most numerous and featured the compounds with the highest peak intensities (Figure S4a; Table 3). The analysis of FA composition revealed that DGs were mainly composed of FA 18:1, in contrast to TGs, which showed a predominance of FA 18:2, the only one present in MGEs, and of FA 18:3 (Figure S4b). Notably, TGs were the only acylglycerol subclass displaying oxidized FAs on the glycerol core.

3.1.4. Triterpenoids

The analysis of the mass spectrometric data allowed us to ascertain the occurrence in the ethanolic extract of the Styrian pumpkin seeds of specialized metabolites belonging to the triterpenoid class, a large group of natural products, derived biosynthetically from the acyclic C-30 hydrocarbon squalene, most of which show tetracyclic and pentacyclic skeletons. Known for their roles in plant development processes and defense response, triterpenoids are characterized by a wide range of biological activities, including anti-inflammatory, anti-proliferative, antidiabetic, hepatoprotective, antimicrobial, antimycotic, analgesic, immunomodulatory, and cardiotonic [50,51].
The analysis of the tandem mass spectrum of the [M + H]+ ion at m/z 682.4452 (59), characterized by the molecular formula C44H59O5N, highlighted the occurrence of a diagnostic product ion at m/z 527.3889 (C37H51O2), originated by contemporary neutral losses of a water molecule and of a C7H7O2N unit corresponding to an aminobenzoic acid, along with a product ion at m/z 405.3508 (C30H45) formed by neutral loss of a benzoic acid unit (Table 4). This fragmentation pattern and the literature data allowed us to identify the C30 skeleton as that of multiflorane-type triterpenoids, in agreement with that previously reported by [52] that, in the seeds of C. pepo, described the occurrence of an O-p-aminobenzoyl-O-benzoyl-multifloren-triol derivative along with two other specialized metabolites of this class, the O-aminobenzoyl-O-benzoyl-multiflora-dien-diol and O-aminobenzoyl-multiflora-dien-diol, which could correspond respectively to compound 99, the dehydrated form of 59, and compound 60, the debenzoylated form of 99 (Table 4).
By considering the mass spectrometric fragmentation pathway described above, the structures of four new multiflorane derivatives could be tentatively assigned to compound 36, likely corresponding to the debenzoylated form of 59, i.e., the O-aminobenzoyl-multifloren-triol derivative, to compound 38, likely the monoesterified form of bryonolic acid with an aminobenzoic acid, to compound 42, likely corresponding to the esterified form of 36 with another aminobenzoic acid, and to compound 45, likely corresponding to the acetylated form of 36, i.e., the O-aminobenzoyl-O-acetyl-multifloren-triol, respectively (Table 4).
Analogously, the structure of the other four triterpenoids could be assigned as that of two multiflora-dien-diol derivatives (40 and 43), likely karounidiol and its isomer isokarounidiol, a multiflora-trien-diol derivative (39), likely dehydrokarounidiol, and an oxo-multiflorenoic acid derivative (41), likely bryononic acid, all of them already described in some Cucurbitaceae species [53,54,55,56] (Table 4) but never reported before in pumpkin (Table 1). The finding of multiflorane-type triterpenoids in the seeds of C. pepo var. styriaca is noteworthy and might suggest a potential basis for their medicinal and nutraceutical interest, considering the melanogenesis inhibitory, cancer-preventing, and antioxidant properties previously described for this chemical class [51,57]. In the absence of targeted bioassays, any direct involvement of the identified compounds remains speculative; however, it could be tentatively proposed that the specific core arrangement of these multiflorane derivatives—including oxygenation patterns at C-3, C-7, and C-29, and esterification with aromatic groups like p-aminobenzoic acid (PABA) or benzoyl moieties—could influence their radical scavenging capacity or interact with intracellular signaling pathways (e.g., NF-κB/MAPK). Furthermore, one might speculate that the rigid, hydrophobic planar core of the multiflorane skeleton could interact with the fluid domains of the stratum corneum lipid matrix. By theoretically mimicking cholesterol, these compounds might assist in stabilizing compromised epidermal membranes, modulating membrane fluidity and protecting keratinocyte integrity together with Cer-EOS.

3.1.5. Oxylipins

The analysis of HRMSMS data acquired in negative ionization mode concurred to identify as fourth lipid class, in order of detected components, that of oxylipins, bioactive lipid mediators produced from the polyunsaturated fatty acid (PUFA) oxidative metabolism, differing each other for the degree of unsaturation and oxygenation of the acyl chains, and described as involved in in vivo inflammatory cascades, pain perception, and skin barrier integrity [23,57]. The detection in tandem mass spectra of main product ions originated by consecutive neutral losses of water molecules allowed to promptly identify in the structure both the occurrence and the number of hydroxy groups, whose presence could be furthermore supported by the detection of diagnostic product ions formed by a CHOH→CHO rearrangement involving the hydroxyl groups and generating shortened aldehydic acyl chains from the end-part or the head-part of the oxylipin (Table 5). On the other hand, by considering the elution order trend, showing the earlier elution for trihydroxylated with respect to di- and monohydroxylated oxylipins such as for diunsaturated oxylipins with respect to the monounsaturated ones, the identification at delayed retention times of di- and mono-unsaturated oxo-forms could be supposed (31, 33), moreover supported by the fragmentation pattern, showing, e.g., as main product ion that originated by neutral loss of a CO2 molecule instead of those formed by dehydroxylation (Table 5) [19,23,31,32]. To our knowledge, this is the first study reporting these metabolites in Styrian pumpkin seeds, since only phytoprostane-type oxylipins have been described for this variety so far [14].

3.1.6. Glycolipids

The least represented class of lipids in the extract of Styrian pumpkin seed was that of glycolipids (GLs), which included only three compounds (Table 5). Glycolipids are the major components of photosynthetic membranes and have been reported to display antiviral, antitumor, and anti-inflammatory activities [19,23,31,58]. Structurally, they are characterized by different combinations of fatty acids esterified at the sn-1 and sn-2 positions of the glycerol unit, but differing in the nature of the sugar moiety linked at the sn-3 position, so composing different subclasses, such as that of digalactosyldiacylglicerols (DGDGs) and the sulfoquinovosyldiacylglycerols (SQDGs), made up of galactose or sulfoquinovose, respectively (Table 5). Thereby, the metabolites belonging to these two GL subclasses can be easily distinguished already on the basis of their different molecular formulae, that, e.g., include a sulfur atom in the case of SQDG, and of course by their fragmentation pattern. So, the molecular formula C39H74O12S detectable in Styrian pumpkin seed (37, Table 5) could be assigned to an SQDG-type metabolite by checking the presence in the HRMSMS spectrum of the product anion at m/z 225, originated from the cleavage of glycerol-sugar ether linkage and resulting in the formation of an epoxydic bridge between carbon 1 and 2 of the sulfoquinovosylic ring. Analogously, the assignment of the two detected DGDGs (75, 79) could be supported by the finding in the tandem mass spectra of the product cation generated by neutral loss of the monodehydrated form of galactose, along with those formed by neutral loss of the whole acyl chain (Table 5). By considering the acyl chain types composing the structures of identified GLs, the predominance of FA 18:2 could be observed in DGDGs, while the only found SQDG was formed by shorter saturated acyl chains, i.e., 14:0 and 16:0 (Table 5).

4. Conclusions

In conclusion, the results provided in this study allowed us to broaden the knowledge on lipid composition of the edible seeds of the Styrian pumpkin variety, in particular highlighting the presence of different lipid classes, ranging from the more polar ones, such as phospholipids, sphingolipids and glycolipids, to the neutral ones, such as acylglycerols, up to including low molecular weight lipids, such as oxylipins.
Particularly interesting is the identification of the Cer-EOS-type ceramide lipid subclass, described here for the first time in pumpkin and characterized by compounds displaying some of the highest peak intensities among all the identified lipid classes. The presence of these ceramides could enhance the functional value of the edible seeds of the Styrian pumpkin variety, suggesting their potential interest as a dietary supplement. Although future targeted bioassays are required to confirm any direct health benefits, it might tentatively be hypothesized that these compounds could play a role in supporting the management of skin inflammation. This assumption would align with literature reports on the anti-inflammatory properties of the Styrian pumpkin seeds, although a distinction must be made since those studies focus on the oil matrix rather than an alcoholic extract.
Moreover, it is noteworthy that this method of analysis allowed us to ascertain the occurrence in the seeds of Cucurbita pepo var. styriaca of specialized metabolites such as the multiflorane-type triterpenoids, some of which have never been described before in pumpkin. Representing a particular chemical class of metabolites with melanogenesis-inhibitory, cancer-preventing, and antioxidant activities reported in the literature, their occurrence further highlights the chemical complexity and potential nutraceutical value of these edible seeds.
In conclusion, the results of this chemical profiling study can be considered a preliminary baseline that opens promising perspectives for future investigations focused on the absolute quantification and biological activity verification of the newly identified classes of lipids and specialized metabolites.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/foods15122215/s1. Figure S1. Chemical classes of compounds present in the ethanolic extract of the seeds of C. pepo var. styriaca. Figure S2a–d. Representation of the six PL subclasses. Figure S3a–d. Representation of SL structural types. Figure S4a,b. Representation of the three AG subclasses.

Author Contributions

A.P.: formal analysis, investigation, software, data curation. A.N.: writing—original draft, software, methodology, investigation, data curation, conceptualization. F.S.: conceptualization. M.M.: writing—review and editing, conceptualization. S.P.: writing—review and editing, supervision, funding acquisition, conceptualization. All authors have read and agreed to the published version of the manuscript.

Funding

This research received external funding by the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.4—Call for tender No. 3138 of 16 December 2021, rectified by Decree n.3175 of 18 December 2021 of Italian Ministry of University and Research funded by the European Union—NextGenerationEU; Project code CN_00000033, Concession Decree No. 1034 of 17 June 2022 adopted by the Italian Ministry of University and Research, CUP: D43C22001260001, Project title “National Biodiversity Future Center—NBFC”.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The original contributions presented in this study are included in the article/Supplementary Materials. Further inquiries can be directed to the corresponding authors.

Conflicts of Interest

The authors declare no conflicts of interest.

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Foods 15 02215 g001
Figure 1. Proposed de novo MS/MS fragmentation pathway of the Cer-(EO)LCB subclass (case study compound 149, precursor ion at m/z 806.7240). The scheme illustrates the manual structural elucidation based on HRMSMS spectra: (A) the primary cleavage driving the neutral loss of the intact d16:1 long-chain base (LCB) to yield the stable dual-acyl core product ion at m/z 535.4723 (C34H63O4); (B) the ester bond cleavage yielding the a,w-dihydroxylated inner acyl chain (FA O) as the diagnostic 3-oxygen product ion at m/z 299.2587 (C18H35O3); and (C) the ester bond cleavage yielding the outer acyl chain as a minor monodehydrated product ion at m/z 237.2212 (C16H29O). Note: The position of the double bond within the outer acyl chain (FA E) structure is tentative and illustrative only, as the exact double bond localization has not been assigned.
Figure 1. Proposed de novo MS/MS fragmentation pathway of the Cer-(EO)LCB subclass (case study compound 149, precursor ion at m/z 806.7240). The scheme illustrates the manual structural elucidation based on HRMSMS spectra: (A) the primary cleavage driving the neutral loss of the intact d16:1 long-chain base (LCB) to yield the stable dual-acyl core product ion at m/z 535.4723 (C34H63O4); (B) the ester bond cleavage yielding the a,w-dihydroxylated inner acyl chain (FA O) as the diagnostic 3-oxygen product ion at m/z 299.2587 (C18H35O3); and (C) the ester bond cleavage yielding the outer acyl chain as a minor monodehydrated product ion at m/z 237.2212 (C16H29O). Note: The position of the double bond within the outer acyl chain (FA E) structure is tentative and illustrative only, as the exact double bond localization has not been assigned.
Foods 15 02215 g001
Table 1. Phospholipids tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Table 1. Phospholipids tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Phospholipids
N°CompoundRt (min)Molecular Formula[M-H]−[(M + HCO2H)-H]−RDBppm[M + H]+RDBppmHRMS/MSMS Peak
Intensity (NL)
3l-PC (18:2-O2)8.51C26H50O9NP 596.32203.53.23 293.2121 (C18H29O3); 242.0790 (C7H17O6NP); 224.0701 (C7H15O5NP); 78.9577(O3P)1.79 × 105
552.33002.50.66184.0734 (C5H15O4NP); 125.0004 (C2H6O4P)2.18 × 105
4l-PC (18:2-O)9.18C26H50O8NP 580.32653.53.49 520.3049 (C25H47O8NP); 295.2278 (C18H31O3); 224.0692 (C7H15O5NP)1.09 × 105
536.33512.50.85184.0736 (C5H15O4NP); 125.0003 (C2H6O4P)1.10 × 105
6l-PC (18:0-O2)10.08C26H52O9NP 598.33702.53.18 295.2283 (C18H31O3)4.31 × 104
554.34591.51.27184.0736 (C5H15O4NP)5.85 × 104
7NA-GPE (18:3)10.24C23H42O7NP474.2631 4.53.38 400.2259 (C20H35O5NP); 171.0048 (C3H8O6P); 152.9948 (C3H6O5P)4.46 × 105
476.27743.50.58304.2640 (C20H34ON)5.45 × 105
8l-PC (16:2)10.38C24H46O7NP 536.29943.52.02 251.2015 (C16H27O2); 224.0693 (C7H15O5NP)4.21 × 104
492.30882.50.76184.0737(C5H15O4NP)5.76 × 104
10l-PC (14:0)10.70C22H46O7NP 512.29961.52.47 227.2012 (C14H27O2); 224.0689 (C7H15O5NP)6.37 × 104
468.30870.50.47184.0737 (C5H15O4NP)1.04 × 105
12l-PI (18:2)11.24C27H49O12P595.2896 4.53.05 315.0512 (C9H16O10P); 279.2344 (C18H31O2); 241.0115 (C6H10O8P); 152.9948 (C3H6O5P)1.01 × 106
597.30363.50.35337.2735 (C21H37O3)5.73 × 104
13NA-GPE (18:2)11.55C23H44O7NP476.2780 3.51.79 402.2407 (C20H37O5NP); 152.9947 (C3H6O5P)1.51 × 106
478.29312.50.64306.2791 (C20H36ON)3.11 × 106
14l-PI (18:2)11.82C27H49O12P595.2888 4.51.63 415.2245 (C21H36O6P); 315.0484 (C9H16O10P); 279.2326 (C18H31O2); 241.0114 (C6H10O8P); 152.9947 (C3H6O5P); 78.9577 (O3P)4.24 × 106
597.30333.5−1.08337.2736 (C21H37O3); 263.2368 (C18H31O); 155.0104 (C3H8O5P)3.01 × 105
15Ether-l-PI (O-16:2)11.93C25H47O11P 555.29252.5−0.61313.2737 (C19H37O3); 239.2365 (C16H31O); 155.0104 (C3H8O5P)5.22 × 105
17l-PC (18:3)12.13C26H48O7NP 562.31474.51.34 277.2168 (C18H29O2); 224.0689 (C7H15O5NP); 168.0427 (C4H11O4NP)5.98 × 105
518.32423.50.08500.3164 (C26H47O6NP); 184.0736(C5H15O4NP)8.62 × 105
19l-PI (16:0)12.52C25H49O12P571.2887 2.51.15 391.2247 (C19H36O6P); 315.0486 (C9H16O10P); 255.2326 (C16H31O2); 241.0113 (C6H10O8P); 152.9947 (C3H6O5P); 78.9577 (O3P)1.98 × 106
573.30331.5−0.28313.2737 (C19H37O3); 155.0104 (C3H8O5P)1.24 × 105
20l-PE (18:2)12.89C23H44O7NP476.2776 3.50.70 279.2327 (C18H31O2); 214.0479 (C5H13O6NP); 196.0373 (C5H11O5NP)1.36 × 107
478.29212.5−1.47337.2733 (C21H37O3)1.31 × 107
21l-PE (16:0)12.93C21H44O7NP452.2778 1.51.47 255.2340 (C16H31O2); 214.0479 (C5H13O6NP); 196.0369 (C5H11O5NP)9.49 × 105
454.29270.5−1.55313.2736 (C19H37O3)7.78 × 105
22l-PC (18:2)12.98C26H50O7NP 564.33003.50.75 504.3067 (C25H47O7NP); 279.2326 (C18H31O2); 242.0795 (C7H17O6NP); 78.9575 (O3P)7.02 × 106
520.33942.5−1.71502.3277 (C26H49O6NP); 337.2740 (C21H37O3); 184.0734 (C5H15O4NP)8.33 × 106
23l-PE (16:0)13.35C21H44O7NP452.2776 1.50.94 255.2326 (C16H31O2); 214.0479 (C5H13O6NP); 196.0371 (C5H11O5NP)6.93 × 106
454.29220.5−1.33313.2737 (C19H37O3)7.04 × 106
24l-PC (18:2)13.38C26H50O7NP 564.32953.5−0.12 504.3097 (C25H47O7NP); 279.2324 (C18H31O2); 224.0688 (C7H15O5NP); 78.9577 (O3P)3.27 × 107
520.33942.5−1.71502.3288 (C26H49O6NP); 337.2730 (C21H37O3); 184.0735 (C5H15O4NP)4.78 × 107
26l-PC (16:0)13.89C24H50O7NP 540.33021.51.12 480.3087 (C23H47O7NP); 255.2325 (C16H31O2); 242.0793 (C7H17O6NP); 224.0685 (C7H15O5NP); 152.9947 (C3H6O5P); 78.9575 (O3P)9.95 × 106
496.33970.5−1.25478.3302 (C24H49O6NP); 313.2736 (C19H37O3); 184.0733 (C5H15O4NP)1.02 × 107
27l-PE (18:1)14.08C23H46O7NP478.2939 2.51.14 281.2483 (C18H33O2); 196.0371 (C5H11O5NP)1.66 × 106
480.30871.50.59339.2893 (C21H39O3)1.77 × 106
28l-PA (18:2)14.23C21H39O7P433.2360 3.52.36 279.2328 (C18H31O2); 171.0055 (C3H8O6P); 152.9947 (C3H6O5P); 78.9577(O3P)1.13 × 106
30l-PC (18:1)14.37C26H54O7NP 566.34652.51.24 506.3265 (C25H49O7NP); 281.2482 (C18H33O2); 242.0793 (C7H17O6NP); 78.9574 (O3P)8.52 × 106
522.35581.5−0.25504.3439 (C26H51O6NP); 339.2877 (C21H39O3); 184.0733 (C5H15O4NP)1.36 × 107
32l-PI (18:0)14.74C27H53O12P599.3207 2.51.43 419.2583 (C21H40O6P); 315.0483 (C9H16O10P); 283.2641 (C18H35O2); 241.0115 (C6H10O8P); 152.9948 (C3H6O5P); 78.9577 (O3P)7.63 × 105
601.33421.5−0.95341.3053 (C21H41O3); 155.0106 (C3H8O5P)6.65 × 104
34l-PE (18:0)15.71C23H48O7NP480.3095 1.52.23 283.2640 (C18H36O2); 196.0372 (C5H11O5NP); 140.0107 (C2H7O4NP)3.95 × 105
482.32480.50.21341.3053 (C21H41O3)4.76 × 105
35l-PC (18:0)15.95C26H54O7NP 568.36301.52.70 508.3408 (C25H51O7NP); 283.2639 (C18H35O2); 242.0801 (C7H17O6NP); 224.0689 (C7H15O5NP); 152.9945 (C3H6O5P)2.14 × 106
524.37160.50.04184.0735 (C5H15O4NP)4.04 × 106
44PI (18:2; 18:2-O2)21.12C45H79O15P889.5097 7.52.71 577.2767 (C27H46O11P); 415.2258 (C21H36O6P); 315.0500 (C9H16O10P); 293.2120 (C18H29O3); 279.2326 (C18H31O2); 241.0115 (C6H10O8P); 223.0007 (C6H8O7P); 152.9948 (C3H6O5P)6.55 × 105
46PI (16:0; 18:2-O1)21.37C43H79O14P849.5154 5.53.54 553.2763 (C25H46O11P); 431.2180 (C21H36O7P); 391.2253 (C19H36O6P); 295.2272 (C18H31O3); 255.2326 (C18H31O3); 241.0116 (C6H10O8P); 152.9961 (C3H6O5P)3.69 × 105
47PI (16:0; 18:2-O2)21.70C43H79O15P865.5101 5.53.28 571.2884 (C25H48O12P); 553.2773 (C25H46O11P); 409.2358 (C19H38O7P); 391.2256 (C19H36O6P); 297.0372 (C9H14O9P); 255.2328 (C16H31O2); 241.0122 (C6H10O8P); 223.0013 (C6H8O7P); 152.9949 (C3H6O5P)2.07 × 106
48PI (16:0; 18:3-O1)22.31C43H77O14P847.4987 6.52.29 391.2270 (C19H36O6P); 293.2120 (C18H29O3); 255.2327 (C16H31O2); 241.0121 (C6H10O8P); 152.9949 (C3H6O5P)3.88 × 104
49PI (18:2; 18:2-O1)22.38C45H79O14P873.5130 7.50.72 593.2735 (C27H46O12P); 577.2795 (C27H46O11P); 431.2203 (C21H36O7P); 415.2245 (C21H36O6P); 315.0495 (C9H16O10P); 295.22278 (C18H31O3); 279.2328 (C18H31O2); 241.0116 (C6H10O8P); 152.9947 (C3H6O5P)5.11 × 105
50PC (18:2-O1; 18:2-O1)22.48C44H80O10NP 858.55156.52.82 295.2279 (C18H31O3); 277.2178 (C18H29O2); 224.0689 (C7H15O5NP)1.68 × 105
814.55965.5−0.22184.0735 (C5H15O4NP); 86.0969 (C5H12N)
51PE (18:2; 18:2-O2)22.52C41H74O10NP770.4989 6.52.19 311.2234 (C18H31O4); 293.2121 (C18H29O3); 279.2327 (C18H31O2); 275.2025 (C18H27O2); 140.0108 (C2H7O4NP)2.43 × 106
52PI (16:0; 18:2-O1)23.08C43H79O14P849.5146 5.52.03 553.2744 (C25H46O11P); 391.2261 (C19H36O6P); 295.2277 (C18H31O3); 255.2325 (C16H31O2); 241.0116 (C6H10O8P); 223.0011 (C6H8O7P); 152.9948 (C3H6O5P)7.01 × 105
53PE (18:2; 18:3-O1)23.21C41H72O9NP752.4875 7.51.93 293.2119 (C18H29O3); 279.2336 (C18H31O2)3.27 × 104
54PE (16:0; 18:2-O2)23.42C39H74O10NP746.4987 4.51.94 452.2794 (C21H43O7NP); 434.2668 (C21H41O6NP); 311.2246 (C18H31O4); 293.2121 (C18H29O3); 255.2326 (C16H31O2); 140.0108 (C2H7O4NP)2.11 × 106
55PE (18:2; 18:1-O2)23.73C41H76O10NP772.5142 5.52.47 295.2281 (C18H31O3); 279.2332 (C18H31O2); 140.0107 (C2H7O4NP)1.94 × 105
56PE (18:1; 18:2-O2)23.80C41H76O10NP772.5139 5.52.08 293.2118 (C18H29O3); 281.2484 (C18H33O2); 140.0105 (C2H7O4NP)4.03 × 105
57PE (18:2; 18:2-O1)24.05C41H74O9NP754.5037 6.51.81 295.2275 (C18H31O3); 279.2326 (C18H31O2); 140.0108 (C2H7O4NP)6.23 × 105
58PI (18:0; 18:2-O2)24.23C45H83O15P893.5403 5.51.28 297.0380 (C9H14O9P); 293.2120 (C18H29O3); 283.2639 (C18H35O2); 241.0114 (C6H10O8P); 152.9949 (C3H6O5P)8.33 × 105
61PE (16:0; 18:1-O2)24.40C39H76O10NP748.5137 3.51.90 295.2276 (C18H31O3); 255.2328 (C16H31O2)2.90 × 106
63PI (18:2; 14:0)24.73C41H75O13P805.4873 5.50.74 577.2776 (C27H46O11P); 525.2458 (C23H42O11P); 363.1934 (C17H32O6P); 279.2328 (C18H31O2); 227.2009 (C14H27O2); 152.9946 (C3H6O5P)1.27 × 106
64PC (18:2; 18:2-O2)24.96C44H80O10NP 858.55006.50.41 504.3091(C25H47O7NP); 415.2249 (C21H36O6P); 293.2121 (C18H29O3); 279.2328 (C18H31O2); 224.0685 (C7H15O5NP); 168.0422 (C4H11O4NP); 78.9578 (O3P)5.96 × 106
814.55765.5−2.76184.0739 (C5H15O4NP); 86.0969 (C5H12N)9.71 × 106
65PI (16:0; 18:3)25.13C43H77O13P831.5034 6.51.21 575.2617 (C27H44O11P); 571.2906 (C25H48O12P); 551.2638 (C25H46O11P); 391.2257 (C19H36O6P); 297.0381 (C9H14O9P); 277.2172 (C18H29O2); 255.2327 (C16H31O2); 241.0116 (C6H10O8P); 223.0006 (C6H8O7P); 152.9947 (C3H6O5P)1.98 × 106
67PI (18:2; 18:2)25.69C45H79O13P857.5186 7.50.35 577.2777 (C27H46O11P); 415.2253 (C21H36O6P); 279.2326 (C18H31O2); 241.0116 (C6H10O8P); 152.9947 (C3H6O5P)3.58 × 107
68PC (16:0; 18:2-O2)26.20C42H80O10NP 834.55074.51.29 480.3102 (C23H47O7NP); 293.2121 (C18H29O3); 255.2325 (C16H31O2); 224.0688 (C7H15O5NP); 168.0420 (C4H11O4NP); 78.9577 (O3P)3.89 × 106
790.55743.5−3.00184.0735 (C5H15O4NP)1.05 × 107
69PC (16:1; 18:2-O1)26.28C42H78O9NP 816.53995.51.63 295.2281 (C18H31O3); 253.2168 (C16H29O2)8.92 × 104
772.54844.5−1.09184.0735 (C5H15O4NP); 86.0969 (C5H12N)5.27 × 105
70PC (16:0; 18:3-O1)26.35C42H78O9NP 816.54105.52.97 293.2124 (C18H29O3); 255.2331 (C16H31O2)1.08 × 105
772.54834.5−0.54184.0736 (C5H15O4NP); 86.0969 (C5H12N)8.83 × 105
71PI (16:0; 18:2)26.36C43H79O13P833.5178 5.5−0.29 553.2784 (C25H46O11P); 391.2249 (C19H36O6P); 297.0373 (C9H14O9P); 279.2326 (C18H31O2); 255.2327 (C16H31O2); 223.0007 (C6H8O7P); 152.9948 (C3H6O5P)1.93 × 108
72PE (18:2; 18:3)26.46C41H72O8NP736.4924 7.51.61 279.2329 (C18H31O2); 277.2173 (C18H29O2); 196.0377 (C5H11O5NP)9.95 × 105
738.50746.50.01597.4871 (C39H65O4); 317.2488 (C21H33O2); 263.2383 (C18H31O)5.05 × 106
73PC (18:2; 18:2-O1)26.62C44H80O9NP 842.55406.5−0.18 295.2272 (C18H31O3); 279.2324 (C18H31O2); 224.0684 (C7H15O5NP); 168.0421 (C4H11O4NP); 78.9575 (O3P)7.99 × 106
798.56325.5−2.15184.0735 (C5H15O4NP)2.53 × 107
74PE (16:1; 18:2)26.85C39H72O8NP 714.50694.5−0.67573.4876 (C37H65O4); 263.2372 (C18H31O); 237.2217 (C16H29O)1.34 × 106
76PE (15:0; 18:2)27.07C38H72O8NP 702.50703.50.27561.4874 (C36H65O4); 337.2736 (C21H37O3); 263.2366 (C18H31O); 225.2212 (C15H29O)1.89 × 106
77PE (16:0; 18:3)27.25C39H72O8NP712.4924 5.51.67 277.2170 (C18H29O2); 255.2325 (C16H31O2); 196.0372 (C5H11O5NP)2.28 × 106
714.50794.50.68573.4866 (C37H65O4); 317.2495 (C21H33O2); 261.2214 (C18H29O)1.53 × 106
78PI (18:1; 18:2)27.38C45H81O13P859.5331 6.5−0.59 579.2944 (C27H48O11P); 417.2408 (C21H38O6P); 297.0378 (C9H14O9P); 281.2481 (C18H33O2); 279.2328 (C18H31O2); 223.0007 (C6H8O7P); 152.9948 (C3H6O5P)2.18 × 107
80PE (18:2; 18:2)27.51C41H74O8NP738.5074 6.50.01 476.2777 (C23H43O7NP); 279.2325 (C18H31O2); 140.0105 (C2H7O4NP)8.22 × 107
740.52225.5−1.09599.5033 (C39H67O4); 337.2737 (C21H37O3); 263.2367 (C18H31O)1.39 × 108
82PI (16:0; 18:1)28.21C43H81O13P835.5336 4.5−0.10 553.2777 (C27H46O11P); 417.2412 (C21H38O6P); 391.2248 (C19H36O6P); 281.2480 (C18H33O2); 255.2324 (C16H31O2); 241.0113 (C6H10O8P); 223.0006 (C6H8O7P); 152.9948 (C3H6O5P)1.21 × 107
84PC (18:1; 18:2-O1)28.29C44H82O9NP 844.57095.51.23 295.2275 (C18H31O3); 281.2482 (C18H33O2); 224.0689 (C7H15O5NP); 168.0420 (C4H11O4NP); 78.9575 (O3P)2.75 × 106
800.57894.5−1.34184.0734 (C5H15O4NP)1.03 × 107
85PE (16:0; 18:2)28.32C39H74O8NP714.5071 4.5−0.41 452.2778 (C21H43O7NP); 279.2325 (C18H31O2); 255.2325 (C16H31O2); 140.0105 (C2H7O4NP)1.38 × 108
716.52183.5−1.73575.5035 (C37H67O4); 337.2744 (C21H37O3); 313.2735 (C19H37O3); 263.2371 (C18H31O); 239.2366 (C16H31O)1.84 × 108
88PC (18:2; 14:0)28.85C40H76O8NP 774.52954.51.96 279.2326 (C18H31O2); 227.2009 (C14H27O2); 224.0691 (C7H15O5NP); 168.0421 (C4H11O4NP); 78.9577 (O3P)2.66 × 106
730.53673.5−1.99184.0733 (C5H15O4NP)1.28 × 107
89PI (18:0; 18:2)28.88C45H83O13P861.5496 5.50.36 581.3091(C27H50O11P); 419.2560 (C21H40OP); 283.2640 (C18H35O2); 279.2324 (C18H31O2); 241.0113 (C6H10O8P); 223.0006 (C6H8O7P); 152.9947 (C3H6O5P)6.53 × 107
90PC (18:2; 18:3)28.97C44H78O8NP 824.54537.52.04 279.2325 (C18H31O2); 277.2169 (C18H29O2); 224.0689 (C7H15O5NP); 168.0420 (C4H11O4NP); 78.9575 (O3P)2.11 × 106
780.55306.5−1.03184.0734 (C5H15O4NP)8.48 × 106
92PE (18:1; 18:2)29.18C41H76O8NP740.5235 5.50.63 478.2933 (C23H45O7NP); 476.2767 (C23H43O7NP); 281.2482 (C18H33O2); 279.2327 (C18H31O2); 140.0107 (C2H7O4NP)2.52 × 107
742.53744.5−1.79601.5190 (C39H69O4); 339.2884 (C21H39O3); 337.2736 (C21H37O3); 265.2527 (C18H33O); 263.2372 (C18H31O)3.97 × 107
94PC (16:1; 18:2)29.51C42H78O8NP 800.54585.52.02 478.2954 (C23H45O7NP); 279.2325 (C18H31O2); 253.2168 (C16H29O2); 168.0418 (C4H11O4NP); 78.9575 (O3P)7.10 × 106
756.55304.5−1.00184.0734 (C5H15O4NP)1.70 × 107
95PC (18:2; 18:2)30.03C44H80O8NP 826.55926.5−0.73 504.3087 (C25H47O7NP); 279.2325 (C18H31O2); 224.0687 (C7H15O5NP); 168.0422 (C4H11O4NP); 78.9575 (O3P)1.57 × 108
782.56795.5−2.38184.0734 (C5H15O4NP); 124.9998 (C2H6O4P); 86.0969 (C5H12N)4.45 × 108
97PC (16:0; 18:2)30.71C42H80O8NP 802.55864.50.00 480.3074 (C23H47O7NP); 279.2326 (C18H31O2); 255.2326 (C16H31O2); 168.0423 (C4H11O4NP); 78.9574 (O3P)1.46 × 108
758.56723.5−2.94184.0732 (C5H15O4NP); 124.9998(C2H6O4P); 86.0969 (C5H12N)4.71 × 108
100PC (18:2; 18:1)31.41C44H82O8NP 828.5751
5.5−0.46 506.3248 (C25H49O7NP); 281.2485 (C18H33O2); 279.2326 (C18H31O2); 224.0683 (C7H15O5NP); 168.0421 (C4H11O4NP); 78.9576 (O3P)8.08 × 107
784.58344.5−2.09184.0734 (C5H15O4NP); 124.9999 (C2H6O4P); 86.0969 (C5H12N)3.21 × 108
103PC (16:0; 18:1)32.50C42H82O8NP 804.5753
3.50.27 480.3090 (C23H47O7NP); 281.2482 (C18H33O2); 255.2327(C16H31O2); 168.0418 (C4H11O4NP); 78.9576 (O3P)4.20 × 107
760.58392.5−1.53184.0734 (C5H15O4NP); 125.0000 (C2H6O4P); 86.0969 (C5H12N)1.27 × 108
104PC (18:1; 18:1)33.09C44H84O8NP 830.5915
4.50.45 506.3229 (C25H49O7NP); 281.2484 (C18H33O2); 224.0690 (C7H15O5NP); 168.0423 (C4H11O4NP); 78.0575 (O3P)5.15 × 107
786.59923.5−1.97184.0733 (C5H15O4NP); 124.9998 (C2H6O4P); 86.0969 (C5H12N)1.94 × 108
107PEth (18:2; 18:2)34.55C41H73O8P723.4984 6.53.34 461.2671 (C23H42O7P); 279.2325 (C18H31O2); 181.0261 (C5H10O5P); 152.9948 (C3H6O5P); 124.9998 (C2H6O4P)3.21 × 106
109PC (18:0; 18:1)35.05C44H86O8NP 832.60863.52.18 508.3392 (C25H51O7NP); 283.2638 (C18H35O2); 281.2484 (C18H33O2); 224.0689 (C7H15O5NP); 168.0419 (C4H11O4NP); 78.9577 (O3P)3.00 × 106
788.61472.5−2.14184.0733 (C5H15O4NP); 124.9999 (C2H6O4P); 86.0969 (C5H12N)7.85 × 107
111PEth (16:0; 18:2)36.04C39H73O8P699.4982 4.53.20 437.2660 (C21H42O7P); 279.2325 (C18H31O2); 255.2325 (C16H31O2); 181.0263 (C5H10O5P); 152.9947 (C3H6O5P); 124.9998 (C2H6O4P)2.89 × 106
112PEth (16:0; 18:2)36.12C41H74O8P725.5139 5.53.22 461.2687 (C23H42O7P); 279.2328 (C18H31O2); 281.2484 (C18H33O2); 181.0264 (C5H10O5P); 124.9996 (C2H6O4P)9.34 × 105
113PC (20:0; 18:2)36.49C46H88O8NP 858.62344.51.80 311.2954 (C20H39O2); 279.2325 (C18H31O2); 224.0688 (C7H15O5NP); 168.0423 (C4H11O4NP); 78.9577 (O3P)7.24 × 105
814.63143.5−0.76184.0734 (C5H15O4NP); 124.9999 (C2H6O4P); 86.0969 (C5H12N)6.00 × 106
Note: abbreviations: l-PCs, lyso-phosphatidylcholines; NA-GPEs, N-acylglycerophosphatidylethanolamines; l-PEs, lyso-phosphatidylethanolamines; l-PIs, lyso-phosphatidylinositols; l-PA, lyso-phosphatidic acid; PCs, phosphatidylcholines; PEs, phosphatidylethanolamines; PIs, phosphatidylinositols; PEths, phosphatidylethanols. The oxidized acyl chains are abbreviated as, e.g., 18:1-O1 and 18:1-O2 to indicate an 18-carbon chain length with one double bond equivalent and either one or two additional oxygen atoms beyond the carbonyl group. NL: normalized level.
Table 2. Sphingolipids tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Table 2. Sphingolipids tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Sphingolipids
N°CompoundRt (min)Molecular Formula[M–H]−[(M + HCO2H)–H]−RDBppm[M + H]+RDBppmHRMS/MSMS Peak
Intensity (NL)
5LCB (t18:1)9.44C18H37O3N 316.28480.50.82298.2789 (C18H36O2N); 280.2626 (C18H34ON); 262.2529 (C18H32N); 74.0607 (C3H8ON); 60.0450 (C2H6ON)8.18 × 105
9LCB (d18:0)10.45C18H39O2N 302.3056−0.50.70284.2954 (C18H38ON); 254.2852 (C17H36N); 106.0866 (C4H12O2N); 102.0920 (C5H12ON); 88.0762 (C4H10ON)5.77 × 105
11LCB (t18:0)10.83C18H39O3N 318.3005−0.50.84300.2880 (C18H38O2N); 282.2791 (C18H36ON); 270.2794 (C17H36ON); 264.2690 (C18H34N); 122.0814 (C4H12O3N); 90.0556 (C3H8O2N); 74.0606 (C3H8ON); 60.0450 (C2H6ON)1.45 × 106
16LCB (N-acetyl-d18:1)12.01C20H39O3N 342.30011.5−0.47298.2736 (C18H36O2N); 280.2636 (C18H34ON); 262.2528 (C18H32N); 240.2324 (C15H30ON); 88.0762 (C4H10ON); 60.0450 (C2H6ON)3.68 × 105
18LCB (t19:1)12.36C19H39O3N 330.29980.5−1.03312.28973 (C19H38O2N); 300.2903 (C18H38O2N); 294.2792 (C19H36ON); 282.2784 (C18H36ON); 270.2806 (C17H36ON); 264.2697 (C18H34N); 74.0606 (C3H8ON); 60.0450 (C2H6ON)5.34 × 105
62HexCer (d18:2; h16:0)24.51C40H75O9N712.5366758.54254.51.14 550.4831 (C34H64O4N); 532.4731 (C34H62O3N); 296.2590 (C18H34O2N); 271.2272 (C16H31O3); 270.2439 (C16H32O2N); 253.2172 (C16H29O2); 225.2219 (C15H29O)1.95 × 107
714.54973.5−2.41534.4886 (C34H64O3N); 516.4769 (C34H62O2N); 272.2586 (C16H34O2N); 262.2530 (C18H32N)8.73 × 106
66HexCer (d18:2; N16:0)25.62C40H75O8N696.5406742.54824.5−0.44 534.4885 (C34H64O3N); 296.2598 (C18H34O2N); 255.2329 (C16H31O2); 254.2488 (C16H32ON); 237.2213 (C16H29O); 235.2061 (C16H27O)1.27 × 106
698.55603.5−0.74518.44988 (C34H64O2N); 280.2632 (C18H34ON); 262.2529 (C18H32N)1.00 × 106
81Cer (t18:1; N18:2)27.71C36H67O4N576.4986622.50574.5−0.06 334.2759 (C21H36O2N); 322.2744 (C20H36O2N); 320.2588 (C20H34O2N); 279.2327 (C18H31O2); 278.2493 (C18H32ON); 265.2162 (C17H29O2)1.54 × 105
83Cer (t18:1; N16:0)28.27C34H67O4N552.4990598.50522.50.64 516.4817 (C34H62O2N); 310.2748 (C19H36O2N); 298.2749 (C18H36O2N); 265.2169 (C17H29O2); 255.2327 (C16H31O2); 254.2492 (C16H32ON); 253.2189 (C16H29O2)3.63 × 105
554.51481.50.98536.5062 (C34H66O3N); 518.4940 (C34H64O2N); 316.2837 (C18H38O3N); 298.2744 (C18H36O2N); 280.2630 (C18H34ON); 262.2535 (C18H32N); 250.2528 (C17H32N); 60.0451 (C2H6ON)4.46 × 105
86Cer (d18:2; h16:0)28.41C34H65O4N550.4834596.48923.50.75 312.2528 (C18H34O3N); 296.2593 (C18H34O2N); 278.2489 (C18H32ON); 271.2280 (C16H31O3); 270.2436 (C16H32O2N); 253.2189 (C16H29O2); 225.2224 (C15H29O)3.14 × 105
91Cer (d18:0; h16:0)29.02C34H69O4N554.5154600.52091.52.08 310.2751 (C19H36O2N); 298.2751 (C18H36O2N); 267.2332 (C17H31O2); 255.2327 (C16H31O2)2.35 × 105
556.53010.50.38538.5208 (C34H68O3N); 318.2993 (C18H40O3N); 300.2895 (C18H38O2N); 282.2791 (C18H36ON); 264.2684 (C18H34N); 256.2640 (C16H34ON); 60.0451 (C2H6ON)4.04 × 105
96Cer (d18:2; N16:0)30.30C34H65O3N534.4883580.49413.50.50 296.2590 (C18H34O2N); 280.2647 (C18H34ON); 261.2222 (C18H29O); 255.2326 (C16H31O2); 254.2488 (C16H32ON); 237.2210 (C16H29O); 235.2065 (C16H27O)1.12 × 106
536.50342.5−0.67280.2640 (C18H34ON); 262.2529 (C18H32N)4.84 × 105
101Cer (d18:0; N16:0)31.68C34H69O3N538.5195584.52581.50.29 280.2641 (C18H34ON); 255.2335 (C16H31O2)7.33 × 105
540.53500.50.02522.5254 (C34H68O2N); 504.5153 (C34H66ON); 302.3037 (C18H40O2N); 284.29503 (C18H38ON); 266.2843 (C18H36N); 256.2637 (C16H34ON); 60.0451 (C2H6ON)1.16 × 106
117Cer-(EO)LCB (t18:1/39:5)
(t18:1; O21:2; E18:3)		39.06C57H101O7N 912.76237.5−3.61597.4878 (C39H65O4); 337.2746 (C21H37O3); 261.2213 (C18H29O); 243.2106 (C18H27)8.81 × 107
118Cer-(EO) LCB (t18:3/39:4)
(t18:3; O21:2; E18:2)		39.40C57H99O7N 910.74828.5−1.99599.5040 (C39H67O4); 337.2736 (C21H37O3); 277.2161 (C18H29O2)4.19 × 107
120Cer-(EO) LCB (t18:1/39:4)
(t18:1; O21:2; E18:2)		39.45C57H103O7N 914.77956.5−1.97599.5033 (C39H67O4); 337.2753 (C21H37O3); 277.2149 (C18H29O2); 261.2215 (C18H29O)7.45 × 107
122Cer-(EO) LCB (t18:2/37:2)
(t18:2; O19:0; E18:2)		39.64C55H101O7N 888.76415.5−1.66575.5041 (C37H67O4); 313.2748 (C19H37O3); 261.2214 (C18H29O); 243.2113 (C18H27)4.30 × 107
126Cer-(EO) LCB (t18:3/39:3)
(t18:3; O21:2; E18:1)		40.13C57H101O7N 912.76337.5−2.49601.5208 (C39H69O4); 337.2743 (C21H37O3); 277.2162 (C18H29O2)6.41 × 107
129Cer-(EO) LCB (t18:1/39:3)
(t18:1; O21:1; E18:2)		40.25C57H105O7N 916.79445.5−2.79601.5192 (C39H69O4); 339.2890 (C21H39O3)5.66 × 107
131Cer-(EO) LCB (t18:2/37:2)
(t18:2; O21:2; E16:0)		40.70C55H101O7N 888.76395.5−1.92575.5037 (C37H67O4); 337.2727 (C21H37O3)3.54 × 107
132Cer-(EO) LCB (d16:1/33:2)
(d16:1; O17:1; E16:1)		40.73C49H91O6N 790.69224.5−0.31519.4400 (C33H59O4); 283.2270 (C17H31O3); 237.2212 (C16H29O); 219.2111 (C16H27)7.52 × 105
133Cer-(EO) LCB (t18:2/39:3)
(t18:2; O21:2; E18:1)		40.83C57H103O7N 914.77866.5−2.97601.5177 (C39H69O4); 337.2744 (C21H37O3); 277.2161 (C18H29O2)5.59 × 107
137Cer-(EO) LCB (d16:1/32:1)
(d16:1/O16:0; E16:1)		41.09C48H91O6N 778.69333.51.07507.4410 (C32H59O4); 271.2276 (C16H31O3); 237.2216 (C16H29O); 219.2115 (C16H27)1.30 × 106
138Cer-(EO) LCB (t18:1/39:2)
(t18:1/O21:1; E18:1)		41.12C57H107O7N 918.81044.5−2.35603.5341 (C39H71O4); 339.2892 (C21H39O3); 269.2373 (C18H31O); 245.2263 (C18H29)4.20 × 107
139Cer-(EO) LCB (d18:1/31:1)
(d18:1/O16:0; E15:1)		41.22C49H93O6N 792.70833.50.25493.4266 (C31H57O4); 271.2267 (C16H31O3); 237.2213 (C16H29O); 219.2110 (C16H27)7.92 × 106
140Cer-(EO) LCB (d16:1/34:2)
(d16:1; O18:1; E16:1)		41.23C50H93O6N 804.70794.5−0.20533.4571 (C34H61O4); 297.2426 (C18H33O3); 237.2211 (C16H29O); 219.2110 (C16H27)1.35 × 106
141Cer-(EO) LCB (d16:1/31:0)
(d16:1; O15:0; E16:0)		41.28C47H91O6N 766.69242.50.68495.4406 (C31H59O4); 257.2116 (C15H29O3); 239.2376 (C16H31O); 211.2059 (C14H27O); 183.1748 (C12H23O)4.19 × 106
142Cer-(EO) LCB (d18:2/33:1)
(d18:2; O17:0; E16:1)		41.28C51H95O6N 818.72264.5−1.42521.4575 (C33H61O4); 285.2422 (C17H33O3)1.40 × 106
143Cer-(EO) LCB (d18:2/35:2)
(d18:2; O17:0; E18:2)		41.39C53H97O6N 844.73965.50.24547.4724 (C35H63O4); 285.2430 (C17H33O3); 263.2374 (C18H31O)1.44 × 107
144Cer-(EO) LCB (d16:1/33:1)
(d16:1; O17:0; E16:1)		41.39C49H93O6N 792.70793.5−0.21521.4574 (C33H61O4); 285.2430 (C17H33O3); 237.2218 (C16H29O); 219.2105 (C16H27)7.92 × 106
145Cer-(EO) LCB (t18:2/39:2)
(t18:2; O21:1; E18:1)		41.40C57H105O7N 916.79535.5−1.72603.5350 (C39H71O4); 339.2905 (C21H39O3); 279.2322 (C18H31O2); 261.2214 (C18H29O)4.82 × 107
146Cer-(EO) LCB (d16:1/33:2)
(d16:1; O17:1; E16:1)		41.43C51H95O6N 818.72314.5−0.84519.4418 (C33H59O4); 283.2271 (C17H31O3); 237.2213 (C16H29O);3.86 × 106
147Cer-(EO) LCB (d16:1/35:2)
(d16:1; O19:1; E16:1)		41.54C51H95O6N 818.72304.5−0.98547.4715 (C35H63O4); 311.2584 (C19H35O3); 237.2221 (C16H29O)2.89 × 106
148Cer-(EO) LCB (d16:1/39:4)
(d16:1; O21:2; E18:2)		41.60C57H101O6N 896.76887.5−1.52599.5032 (C39H67O4); 337.2740 (C21H37O3); 319.2634 (C21H35O2); 263.2372 (C18H31O); 245.2267 (C18H29)3.02 × 108
149Cer-(EO) LCB (d16:1/34:1)
(d16:1; O18:0; E16:1)		41.86C50H95O6N 806.72403.50.29535.4723 (C34H63O4); 299.2587 (C18H35O3); 237.2212 (C16H29O)3.71 × 106
150Cer-(EO) LCB (t18:2/39:1)
(t18:2; O21:1; E18:0)		41.91C57H107O7N 918.81074.5−2.01605.5483 (C39H73O4); 339.2897 (C21H39O3); 265.2527 (C18H33O)1.51 × 107
151Cer-(EO) LCB (d18:2/33:0)
(d18:2; O17:0; E16:0)		41.96C51H97O6N 820.73833.5−0.64523.4726 (C33H63O4); 285.5430 (C17H33O3); 239.2374 (C16H31O);9.42 × 106
152Cer-(EO) LCB (d18:2/37:2)
(d18:2; O19:0; E18:2)		41.98C55H101O6N 872.76865.5−1.73575.5036 (C37H67O4); 313.2738 (C19H37O3); 263.2366 (C18H31O); 239.2373 (C16H31O)2.86 × 108
153Cer-(EO) LCB (d18:2/39:3)
(d18:2; O21:2; E18:1)		42.00C57H103O6N 898.78416.5−1.95601.5194 (C39H69O4); 337.2735 (C21H37O3); 265.2527 (C18H33O)2.39 × 108
154Cer-(EO) LCB (d16:1/35:1)
(d16:1; O19:0; E16:1)		42.03C51H97O6N 820.73853.5−1.16549.4878 (C35H65O4); 313.2736 (C19H37O3); 237.2214 (C16H29O)9.42 × 106
155Cer-(EO) LCB (d16:0/39:4)
(d16:0; O21:2; E18:2)		42.05C55H101O6N 872.76885.5−2.19599.5030 (C39H67O4); 337.2743 (C21H37O3); 263.2368 (C18H31O)2.75 × 108
Note: abbreviations: LCBs, long chain bases; HexCers. Hexosylceramides; Cers, ceramides; Cer-(EO)LCB, Cer = ceramide, E = second fatty acid, esterified at the ω-position of the N-acylated fatty acid, O = α,ω-dihydroxylated fatty acid N-acylated to the LCB. The nomenclature for long-chain bases (LCBs) consists of an initial letter, ‘d’ for dihydroxylated bases (e.g., d18:0) or ‘t’ for trihydroxylated ones (e.g., t18:1), followed by two numbers separated by a colon to indicate the number of carbons and double bonds. Additionally, in Cer and HexCer nomenclature, N-acylated fatty chains are designated by adding the letter ‘h’ or ‘N’ to the carbon chain length and double bond equivalents to indicate whether they are hydroxylated, usually at the C-2 position (e.g., HexCer(d18:2; h16:0)), or non-hydroxylated, respectively (e.g., Cer(t18:1; N18:2)). In Cer-(EO)LCB nomenclature, the first pair of brackets contains the LCB type followed by a slash and two numbers separated by a colon, indicating the total carbon chain length and number of double bonds of the fatty acyl portion (e.g., d16:1/34:1). The second pair of brackets designates the esterified structure: the α,ω-dihydroxylated fatty acid N-acylated to the LCB is indicated by ‘O’, while the fatty acid esterified at the ω-position of ‘O’ is indicated by ‘E’, with both followed by their respective carbon chain length and double bonds (e.g., d16:1; O18:0; E16:1). NL: normalized level.
Table 3. Acylglicerols tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Table 3. Acylglicerols tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Acylglicerols
N°CompoundRt (min)Molecular Formula[M–H]−[(M + HCO2H)–H]−RDBppm[M + H]+RDBppmHRMS/MSMS Peak
Intensity (NL)
87MGE (O-18:2; 18:2)28.55C39H70O4 603.53414.5−1.04263.2372 (C18H31O); 267.2681 (C18H35O)2.60 × 107
93MGE (O-16:2; 18:2)29.41C37H66O4 575.50324.5−0.27263.2368 (C18H31O); 239.2370 (C16H31O)1.41 × 107
98DG (18:1; 18:3)30.92C39H68O5 617.51375.5−0.36599.5008 (C39H67O4); 339.2895 (C21H39O3); 335.2587 (C21H35O3); 265.2530 (C18H33O); 261.2217 (C18H29O)1.22 × 107
102DG (16:0; 18:3)32.06C37H66O5 591.49734.5−0.02573.4902 (C37H65O4); 335.2585 (C21H35O3); 313.2738 (C19H37O3); 279.2320 (C18H31O2); 261.2212 (C18H29O); 239.2372 (C16H31O)1.40 × 107
105DG (18:1; 18:3)33.76C39H68O5 617.51345.5−0.84599.5030 (C39H67O4); 339.2907 (C21H39O3); 335.2577 (C21H35O3); 261.2213 (C18H29O)2.60 × 108
106DG (16:0; 18:2)34.52C37H68O5 593.51343.5−0.88575.5017 (C37H67O4); 337.2733 (C21H37O3); 313.2737 (C19H37O3); 263.2366 (C18H31O); 239.2364 (C16H31O)1.33 × 107
108DG (18:1; 18:2)34.78C39H70O5 619.52894.5−0.98601.5196 (C39H69O4); 339.2893 (C21H39O3); 337.2737 (C21H37O3); 265.2519 (C18H33O); 263.2368 (C18H31O)5.98 × 107
110DG (18:1; 18:1)35.93C39H72O5 621.54543.50.25603.5329 (C39H71O4); 339.2893 (C21H39O3); 265.2521 (C18H33O)6.32 × 106
114TG (14:0; 18:2; 18:3)38.69C53H92O6 825.69657.5−0.17615.5013 (C39H67O5); 597.4877 (C39H65O4); 317.2481 (C21H33O2); 285.2433 (C17H33O3); 261.2213 (C18H29O); 211.2062 (C14H27O)5.18 × 106
115TG (16:1; 18:2; 18:3)38.86C55H94O6 851.71198.5−0.48597.4864 (C39H65O4); 573.4883 (C37H65O4); 571.4706 (C37H63O4); 337.2750 (C21H37O3); 317.2483 (C21H33O2); 311.2588 (C19H35O3); 263.2375 (C18H31O); 261.2209 (C18H29O); 237.2214 (C16H29O)8.82 × 106
116TG (18:2; 18:2; 18:3)39.05C57H96O6 877.72669.5−1.60615.5004 (C39H67O5); 599.5040 (C39H67O4); 597.4880 (C39H65O4); 337.2738 (C21H37O3); 317.2489 (C21H33O2); 263.2370 (C18H31O); 261.2219 (C18H29O)2.95 × 108
119TG (18:2; 18:2; 18:3-O1)39.44C57H96O7 893.72149.5−1.89613.4834 (C39H65O5); 599.5052 (C39H67O4); 337.2729 (C21H37O3); 277.2164 (C18H29O2); 263.2367 (C18H31O)1.84 × 108
121TG (16:0; 18:2; 18:3)39.62C55H96O6 853.72667.5−1.58615.4980 (C39H67O5); 597.4879 (C39H65O4); 317.2478 (C21H33O2); 313.2747 (C19H37O3); 263.2368 (C18H31O); 261.2215 (C18H29O); 239.2371 (C16H31O)1.94 × 108
123TG (18:1; 18:2; 18:3)39.78C57H98O6 879.74168.5−2.32601.5181 (C39H69O4); 599.5039 (C39H67O4); 597.4873 (C39H65O4); 339.2897 (C21H39O3); 337.2738 (C21H37O3); 265.2530 (C18H33O); 263.2373 (C18H31O); 261.2218 (C18H29O)2.47 × 108
124TG (16:0; 18:2; 18:3-O1)40.01C55H96O7 869.72177.5−1.38613.4841 (C39H65O5); 589.4836 (C37H65O5); 575.5016 (C37H67O4); 351.2537 (C21H35O4); 337.2749 (C21H37O3); 313.2727 (C19H37O3); 295.2271 (C18H31O3); 277.2165 (C18H29O2); 263.2373 (C18H31O); 239.2371 (C16H31O)1.54 × 108
125TG (16:0; 18:1; 18:3)40.13C55H98O6 855.74296.5−0.88599.5025 (C39H67O4); 577.5186 (C37H69O4); 573.4921 (C37H65O4); 339.2911 (C21H39O3); 335.2609 (C21H35O3); 317.2482 (C21H33O2); 313.2736 (C19H37O3); 265.2533 (C18H33O); 261.2212 (C18H29O)5.47 × 107
127TG (18:1; 18:2; 18:3-O1)40.15C57H98O7 895.73698.5−1.78615.4997 (C39H67O5); 613.4845 (C39H65O5); 601.5207 (C39H69O4); 351.2531 (C21H35O4); 339.2895 (C21H39O3); 337.2745 (C21H37O3); 277.2163 (C18H29O2); 265.2516 (C18H33O); 263.2378 (C18H31O)1.90 × 108
128TG (18:1; 18:1; 18:3)40.21C57H100O6 881.75757.5−1.98603.5333 (C39H71O4); 599.5027 (C39H67O4); 339.2898 (C21H39O3); 265.2523 (C18H33O); 261.2220 (C18H29O)8.84 × 107
130TG (18:0; 18:2; 18:3)40.58C57H100O6 881.75767.5−1.92603.5333 (C39H71O4); 597.4877 (C39H65O4); 341.3072 (C21H41O3); 337.2743 (C21H37O3); 263.2366 (C18H31O) 261.2215 (C18H29O)1.14 × 108
134TG (18:1; 18:1; 18:3-O1)40.88C57H100O7 897.75247.5−1.96615.4972 (C39H67O5); 603.5349 (C39H71O4); 351.2534 (C21H35O4); 339.2890 (C21H39O3); 277.2161 (C18H29O2); 265.2524 (C18H33O)7.77 × 107
135TG (16:0; 18:0; 18:3)40.98C55H100O6 857.75955.5−0.41601.5190 (C39H69O4); 579.5336 (C37H71O4); 573.4866 (C37H65O4); 341.3055 (C21H41O3); 317.2481 (C21H33O2); 313.2744 (C19H37O3); 261.2213 (C18H29O); 239.2375 (C16H31O);4.37 × 106
136TG (18:0; 18:1; 18:3)41.08C57H102O6 883.77396.5−1.12605.5509 (C39H73O4); 601.5182 (C39H69O4); 599.5053 (C39H67O4); 341.3061 (C21H41O3); 339.2905 (C21H39O3); 265.2526 (C18H33O); 261.2215 (C18H29O)2.83 × 107
Note: abbreviations: MGEs, monoacylglycerol ethers; DGs, diacylglycerols; TGs, triacylglycerols. In MGEs, alkyl chains are abbreviated as, e.g., O-18:2 to indicate an 18-carbon chain length with two double bond equivalents, ether-linked to one glycerol oxygen. In TGs, oxidized acyl chains are abbreviated as 18:3-O1 to indicate an 18-carbon chain length with three double bond equivalents and one additional oxygen atom beyond the carbonyl group. NL: normalized level.
Table 4. Triterpenoids tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Table 4. Triterpenoids tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Triterpenoids
N°CompoundRt (min)Molecular Formula[M–H]−[(M + HCO2H)–H]−RDBppm[M + H]+RDBppmHRMS/MSMS Peak
Intensity (NL)
36O-aminobenzoyl-multifloren-triol17.10C37H55O4N 578.420110.50.36560.4075 (C37H54O3N); 423.3618 (C30H47O); 405.3514 (C30H45); 295.2419 (C22H31); 227.1795 (C17H23); 138.0549 (C7H8O2N); 120.0446 (C7H6ON)8.76 × 106
38O-aminobenzoyl-bryonolic acid18.22C37H53O4N 576.405011.50.30439.3584 (C30H47O2); 343.2629 (C23H35O2); 243.1744 (C17H23O); 138.0551 (C7H8O2N); 120.0445 (C7H6ON)2.82 × 105
39Multiflora-trien-diol18.78C30H46O2 439.35717.50.07407.3310 (C29H43O); 365.3196 (C27H41); 323.2375 (C23H31O); 215.1795 (C16H23)3.85 × 106
40Multiflora-dien-diol isomer19.51C30H48O2 441.37276.50.01409.3465 (C29H45O); 367.3357 (C27H43); 311.2373 (C22H31O); 215.1795 (C16H23)3.59 × 106
41Bryononic acid19.67C30H46O3 455.35217.50.17201.1643 (C15H21); 173.1327 (C13H17); 159.1170 (C12H15); 135.1171 (C10H15); 121.1015 (C9H13)4.98 × 105
42di-O-aminobenzoyl-multifloren-triol20.46C44H60O5N2 697.457615.5−0.76423.3615 (C30H47O); 405.3512 (C30H45); 295.2435 (C22H31); 203.1794 (C15H23); 138.0551 (C7H8O2N); 120.0445 (C7H6ON); 109.1014 (C8H13)2.60 × 106
43Multiflora-dien-diol isomer20.48C30H48O2 441.37256.5−0.40409.3464 (C29H45O); 367.3355 (C27H43); 215.1796 (C16H23)2.94 × 106
45O-aminobenzoyl-O-acetyl-multifloren-triol21.16C39H57O5N 620.431311.50.63465.3730 (C32H49O2); 405.3503 (C30H45); 203.1797 (C15H23); 138.0550 (C7H8O2N); 120.0446 (C7H6ON); 109.1015 (C8H13)4.05 × 105
59O-aminobenzoyl-O-benzoyl-multifloren-triol24.25C44H59O5N 682.445215.50.60527.3889 (C37H51O2); 423.3621 (C30H47O); 405.3508 (C30H45); 295.2435 (C22H31); 203.1794 (C15H23); 138.0550 (C7H8O2N); 120.0446 (C7H6ON); 109.1014 (C8H13)8.63 × 107
60O-aminobenzoyl-multiflora-dien-diol25.38C37H53O3N 560.410111.5−0.48542.3983 (C37H52NO2); 423.3619 (C30H47O); 405.3514 (C30H45); 295.2430 (C22H31); 227.1795 (C17H23); 213.1639 (C16H21); 138.0549 (C7H8O2N); 120.0446 (C7H6ON)1.42 × 107
99O-aminobenzoyl-O-benzoyl-multiflora-dien-diol31.38C44H57O4N 664.435516.5−1.55527.3889 (C37H51O2); 405.3508 (C30H45); 295.2435 (C22H31); 138.0550 (C7H8O2N)1.54 × 108
Note: NL: normalized level.
Table 5. Oxylipins and glycolipids were tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Table 5. Oxylipins and glycolipids were tentatively identified in the EtOH extract of C. pepo var. styriaca seeds.
Oxylipins
N°CompoundRt (min)Molecular Formula[M–H]−[(M + HCO2H)–H]−RDBppm[M + H]+RDBppmHRMS/MSMS Peak
Intensity (NL)
1Trihydroxy-octadecadienoic acid2.59C18H32O5327.2176 3.52.93 309.2066 (C18H29O4); 291.1969 (C18H27O3); 229.1439 (C12H21O4); 211.1332 (C12H19O3); 171.1017 (C9H15O3)9.85 × 105
2Trihydroxy-octadecenoic acid3.21C18H34O5329.2336 2.54.12 311.2227 (C18H31O4); 293.2123 (C18H29O3); 229.1441 (C12H21O4); 211.1333 (C12H19O3); 199.1334 (C11H19O3); 171.1017 (C9H15O3)8.18 × 105
25Hydroxy-octadecadienoic acid13.65C18H32O3295.2274 3.52.09 277.2168 (C18H29O2); 195.1381 (C12H19O2); 171.1016 (C9H15O3)8.18 × 106
29Hydroxy-octadecenoic acid14.31C18H34O3297.2432 2.52.72 279.2325 (C18H31O2); 197.1539 (C12H21O2); 183.1382 (C11H19O2)2.45 × 106
31Oxo-octadecadienoic acid14.49C18H29O3293.2122 4.53.85 275.2013 (C18H27O2); 249.2220 (C17H29O); 197.1173 (C11H17O3); 185.1173 (C10H17O3)4.27 × 106
33Oxo-octadecenoic acid15.56C18H32O3295.2281 3.54.36 277.2173 (C18H29O2); 251.2380 (C17H31O); 155.1429 (C10H19O)8.15 × 105
Glycolipids
37SQDG (14:0; 16:0)17.96C39H74O12S765.4812 3.5−1.08 255.2327 (C16H31O2); 225.0075 (C6H9O7S)2.34 × 105
75DGDG (18:2; 18:2)27.01C51H88O15 963.6009
[M + Na]+		7.5−0.68801.5472 (C45H78O10Na); 683.3612 (C33H56O13Na); 521.3081 (C27H46O8Na)3.40 × 106
79DGDG (16:0; 18:2)27.40C49H88O15 939.6021
[M + Na]+		5.50.60777.5496 (C43H78O10Na); 683.3610 (C33H56O13Na); 659.3616 (C31H56O13Na); 521.3104 (C27H46O8Na)1.04 × 106
Note: abbreviations: SQDGs, sulfoquinovosyldiacylglycerols; DGDGs, digalactosyldiacylglicerols. NL: normalized level.
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Paolillo, A.; Napolitano, A.; Sottile, F.; Masullo, M.; Piacente, S. Cucurbita pepo var. styriaca Seeds: Deep Insights into Polar Lipid Profile. Foods 2026, 15, 2215. https://doi.org/10.3390/foods15122215

AMA Style

Paolillo A, Napolitano A, Sottile F, Masullo M, Piacente S. Cucurbita pepo var. styriaca Seeds: Deep Insights into Polar Lipid Profile. Foods. 2026; 15(12):2215. https://doi.org/10.3390/foods15122215

Chicago/Turabian Style

Paolillo, Annunziata, Assunta Napolitano, Francesco Sottile, Milena Masullo, and Sonia Piacente. 2026. "Cucurbita pepo var. styriaca Seeds: Deep Insights into Polar Lipid Profile" Foods 15, no. 12: 2215. https://doi.org/10.3390/foods15122215

APA Style

Paolillo, A., Napolitano, A., Sottile, F., Masullo, M., & Piacente, S. (2026). Cucurbita pepo var. styriaca Seeds: Deep Insights into Polar Lipid Profile. Foods, 15(12), 2215. https://doi.org/10.3390/foods15122215

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