Search Results (22)

It is desirable to find and evaluate innovative sustainable products guaranteeing and increasing the quality and productivity of radish (Raphanus sativus). Compost tea (CT) represents a natural organic preparation providing benefits to the soil–plant system, including a biostimulant action against climate change. Therefore, we evaluated whether CT can influence radish nutraceutical properties and its primary metabolism. In particular, the roots resulting from CT treatment were examined via conventional (total antioxidant and phenol contents) and spectroscopic techniques (high-resolution NMR and NIR) and compared with controls. It was proved that CT exerted a positive effect on the radish quality, which led to a significantly larger size in those treated (TRT), accompanied by higher contents of total antioxidants and phenols. The assignment of ¹H and ¹³C signals in the NMR spectra allowed the delineation of the NMR fingerprint of the radish primary metabolome, which was processed by multivariate statistical analyses (PCA, PLS-DA, and heatmap clusterisation). TRT metabolites exhibited a peculiar profile, characterized by higher levels of glutamine and malic acid, along with lower levels of glucose, fructose, sucrose, lactic acid, and tryptophan. NIR spectroscopy also identified a recognisable profile in TRT, confirming its role as an alternative and accessible technique to appreciate the organic treatment’s effects on radish. Full article

Enzymatic modification of Kraft lignin under alkaline conditions was investigated using bilirubin oxidase (BOD) in borate buffer (pH 10). Control solubilization without enzyme addition revealed a notable increase in molar mass (up to 1.7-fold) and potential borate complexation with lignin hydroxyl groups, as evidenced by thermogravimetric and ¹¹B NMR analyses. BOD treatments induced substantial polymerization, with molar mass increases of up to 4-fold for insoluble fractions after 24 h, while soluble fractions exhibited progressive increases over 5 days. Quantitative ³¹P NMR showed reductions in aliphatic and phenolic hydroxyl groups by 20%, suggesting oxidative coupling reactions, particularly through 4-O-5′ and 5-5′ linkages. Solid-state ¹³C NMR confirmed structural changes associated with polymerization. Dynamic light scattering (DLS) indicated the presence of colloidal aggregates, potentially explaining challenges in HSQC NMR signal acquisition. These findings highlight the efficacy of bilirubin oxidase in catalyzing lignin polymerization and underscore the structural impact of borate–lignin interactions in alkaline media, paving the way for advanced lignin valorization strategies. Full article

In this study, the homogeneous carboxylation of potassium, sodium, and lithium phenolates in DMSO solution at 100 °C by the Kolbe–Schmitt reaction was investigated. The impact of water, phenolate concentration, and cation nature on the yield of products and reaction selectivity was demonstrated. Based on the patterns observed, it was concluded that a complex cluster mechanism governs the carboxylation reaction in the solution. The use of a homogeneous reaction medium allowed for convenient testing of various additives to assess their impact on the reaction. Basic additives such as sodium salts of mesitol, tert-butylcalix[4]arene, sodium isopropyl, and tert-butyl cabonates were found to enhance the reaction, increasing the yield of hydroxybenzoic acids by 20% (to 61.6%). The main product in the DMSO solution was identified as 4-hydroxybenzoic acid, in contrast to the classical Kolbe–Schmitt method which typically yields 2-hydroxybenzoic (salicylic) acid. The use of ¹³C NMR spectroscopy enabled the observation of a “carbonate complex” in the solution for the first time, with the carbonate carbon displaying a chemical shift value of 142 ppm, an unusual finding for stable carbonates, and located between the signals of free dissolved CO₂ and carboxylate derivatives. Full article

(1) Background: A preliminary investigation of Protected Designation of Origin (PDO) wines (red and rosé) produced from Negroamaro grapes—a native Salento (Apulia, Southern Italy) vine that is part of the Salice s.no PDO area—was performed in this work. (2) Methods: ¹H-NMR spectroscopy, in combination with multivariate statistical analysis (MVA), was employed to characterize the metabolic profiles of 39 wine samples. Spectrophotometric methods were used to obtain preliminary information on the phenolic composition of wines and the associated antioxidant activity. The HepG2 liver cell line was used to assess the biological activity (effect on cell viability and genotoxicity activity) of wine samples. (3) Results: The NMR spectra analysis revealed the presence of signals ascribable to phenolic compounds such as gallic, hydroxycinnamic, and syringic acids. Relative content of these metabolites has been shown to be higher in red than in rosés wines and related to the wine producers. Interestingly, a similar pattern was observed in biological analyses. Red wines compared to the rosé wines display great variations in antioxidant capacity when evaluated as fresh samples using the DPPH and ORAC methods. Furthermore, all red wines exhibited a concentration-dependent decrease in cellular viability and live cells; this phenomenon is much less pronounced in rosé wines. (4) Conclusions: The resulting findings from this study reveal that winemaking operations could lead to final products with different chemical compositions and related properties. Even when starting from the same crop variety and cultivation region, significant differences were observed in the wine samples NMR-metabolic profiles and in vitro biotoxicological activity. Full article

The present study evaluated the applicability of ¹H NMR and UV-Vis spectroscopies as analytical techniques for the characterization and determination of biodiesel conversion and for monitoring the oxidative stability of biodiesel samples with antioxidants. For this study, safflower and babassu biodiesels were obtained through transesterification, and physicochemical properties confirmed the success of both reactions. A bench-top accelerated oxidation system was used as an alternative to the Rancimat^® method, with samples of 6.0 g heated at 110 ± 5 °C and collected every 2 h for 12 h. The agreement for biodiesel conversions was good, with divergences between 2% and 0.4% for safflower biodiesel and 1.9% for babassu biodiesel. As for UV-Vis spectroscopy, the technique showed the same trend as the Rancimat^® method, showing efficiency in evaluating the oxidative stability of safflower biodiesel and in the performance of antioxidants BHT and DMP-30. The accuracy of NMR signals integration for mixtures of safflower oil and safflower biodiesel and the use of UV-Vis spectroscopy associated with a bench-top accelerated oxidation system to investigate the performance of phenolic and amine antioxidants in safflower and babassu biodiesel were explored for the first time, showing results close to the standard methods. Therefore, ¹H NMR and UV-Vis spectroscopies could be applied as alternatives to the GC and Rancimat^® methods to determine conversion and monitor the oxidative stability of biodiesel rapidly and practically. Full article

Suaeda glauca, a halophyte in the Amaranthaceae family, exhibits remarkable resilience to high salt and alkali stresses despite the absence of salt glands or vesicles in its leaves. While there is growing pharmacological interest in S. glauca, research on its secondary metabolites remains limited. In this study, chemical constituents of the aerial parts of S. glauca were identified using 1D- and 2D-NMR experiments, and its biological activity concerning hair loss was newly reported. Eight compounds, including alkaloids (1~3), flavonoids (4~6), and phenolics (7 and 8), were isolated. The compounds, except the flavonoids, were isolated for the first time from S. glauca. In the HPLC chromatogram, quercetin-3-O-β-d-glucoside, kaempferol-3-O-β-d-glucoside, and kaempferol were identified as major constituents in the extract of S. glauca. Additionally, the therapeutic potential of the extract of S. glauca and the isolated compounds 1~8 on the expressions of VEGF and IGF-1, as well as the regulation of Wnt/β-catenin signaling, were evaluated in human follicle dermal papilla cells (HFDPCs) and human umbilical vein endothelial cells (HUVECs). Among the eight compounds, compound 4 was the most potent in terms of increasing the expression of VEGF and IGF-1 and the regulation of Wnt/β-catenin. These findings suggest that S. glauca extract and its compounds are potential new candidates for preventing or treating hair loss. Full article

Breast cancer ranks among the most prevalent malignancies affecting women worldwide, and apoptosis-targeting drugs are attractive candidates for the treatment of cancer. In the current study, we investigated the in vitro cytotoxicity of the mushroom Calvatia nipponica in human breast cancer cells (MDA-MB-231), identified potential antitumor compounds through bioactivity-guided isolation, and elucidated the antitumor, pro-apoptotic molecular mechanisms of the identified bioactive compounds. C. nipponica is edible when young, and it has been used as a food source as well as a traditional medicine in wound dressings. However, only a limited number of studies have reported its chemical composition and biological activities. In the screening test, the methanol extract of C. nipponica fruiting bodies exhibited cytotoxicity against MDA-MB-231 cells. Bioactivity-guided fractionation of the methanol (MeOH) extract and chemical investigation of the active fractions resulted in the isolation of fourteen compounds (1–14), including six alkaloids (1–3, 5, 7, and 8), two phenolic compounds (4 and 6), one fatty acid (9), and five steroids (10–14). The structures of the isolated compounds were determined using NMR spectroscopic methods, liquid chromatography–mass spectrometry, and comparison of data with previously reported values. The isolated compounds (1–14) were tested for cytotoxicity against MDA-MB-231 cells, where compound 1, i.e., N,N-dimethyl-anthranilic acid, exhibited the most significant cytotoxicity against MDA-MB-231 cells, with an IC₅₀ value of 90.28 ± 4.23 μM and apoptotic cell death of 56.01% ± 2.64% at 100 μM. Treatment with compound 1 resulted in an upregulation of protein levels, including cleaved caspase-8, cleaved poly (ADP-ribose) polymerase, Bcl-2-associated X protein (Bax), cleaved caspase-3, cleaved caspase-9, Bad, and Cytochrome c, but decreased the levels of B-cell lymphoma 2 (Bcl-2). Overall, these results indicate that N,N-dimethyl-anthranilic acid (1) may have anti-breast cancer activity and is probably involved in the induction of apoptosis mediated by extrinsic and intrinsic signaling pathways. Full article

The utilization of biopolymers gained recent attention worldwide due to their effective role in producing eco-friendly and economical products. Mucilage from Opuntia ficus-indica (OFI, and other succulent plants) has the capacity to absorb huge amounts of water, forming a viscous colloid with interesting rheological properties. It also had the potential ability for use as food additives or food technological products. We, therefore, aimed at extracting and characterizing pure liquid mucilage from the cladodes of OFI (Egyptian variety) using multidimensional approaches including HPLC-RID, FTIR, XRD, NMR, DSC, and TGA assays. The chemical composition, total polyphenols, total flavonoids, total flavonols, and antioxidant capacity by DPPH and ABTS assays were also measured. HPLC-RID analysis showed that the mucilage’s sugars are composed of glucose, xylose, rhamnose, galacturonic acid, arabinose, galactose, and fucose with total sugars of 0.375 mg/mL, which were subsequently confirmed by FTIR and NMR results. The specific signals of these sugars were also observed in ¹³C and ¹H NMR spectra and their chemical fingerprint was obtained by FTIR. XRD patterns showed that mucilage has high calcium content, and the glass transition temperature was observed at 85.9 °C. Meanwhile, total phenolic content, flavonoids, and flavonols were about 7.96 mg GAE/g FW, 3.61 mg QE/g FW, and 1.47 mg QE/g FW, respectively. The antioxidant capacity of mucilage was around 26.15 and 22.5 µmol TE/g FW for DPPH and ABTS methods, respectively. It can be concluded that OFI cladode mucilage showed promising properties that would improve and open new opportunities and trends in the food, pharmaceutical, cosmetic, and other industries. The use of pure liquid mucilage could also be economically profitable due to its low cost, availability, and effectiveness for many edible applications. Full article

The usage of laccases is a sustainable and environmentally friendly approach to modifying the Kraft lignin structure for use in certain applications. However, the inherent structure of Kraft lignin, as well as that resulting from laccase modification, still presents challenges for fundamental comprehension and successful lignin valorization. In this study, bacterial and fungal laccases were employed to modify eucalypt Kraft lignin. To evaluate the type and range of the chemical and structural changes of laccase-treated lignins, different NMR techniques, including solution ¹H and 2D NMR (heteronuclear single quantum correlation (HSQC)), and solid-state ¹³C NMR, were applied. Size exclusion chromatography and infrared spectroscopy were also used. Interestingly, HSQC analysis showed substantial changes in the oxygenated aliphatic region of lignins, showing an almost complete absence of signals corresponding to side-chains due to laccase depolymerization. Simultaneously, a significant loss of aromatic signals was observed by HSQC and ¹H NMR, which was attributed to a deprotonation of the lignin benzenic rings due to polymerization/condensation by laccase reactions. Then, condensed structures, such as α-5′, 5-5′, and 4-O-5′, were detected by HSQC and ¹³C NMR, supporting the increment in molecular weight, as well as the phenolic content reduction determined in lignins. Full article

Mastitis is the commonest disease of bovines imposing a great economic setback and a drastic public health concern worldwide. Antibiotic resistance is the preliminary con of excessive antibiotics use for disease treatment. Studies validate an alarming increase in the antibiotic resistance of both humans and animals. For ages, medicinal plants have been used to treat a number of ailments in humans and animals, including mastitis. Curcuma longa, or turmeric, is the prerequisite in Indian cooking and has been used in traditional medicine for its magical properties. The rhizome of C. longa possesses significant anti-inflammatory, antibacterial, antifungal, and antioxidative properties. In the current study, we evaluated the hexanic and ethanolic extracts of C. longa for their anti-inflammatory and antioxidative potential against LPS-induced inflammation in buffalo mammary epithelial cells (BuMECs). Pretreatment with the extracts downregulated the expression of proinflammatory cytokine TNFα via the TLR4/NFκB-mediated signaling pathway. However, IL-6 was downregulated in only the hexanic C. longa-pretreated group. A significant upregulation of NRF2 mRNA expression was seen in both hexanic- and ethanolic-treated groups. A GC-MS/MS study of the extracts revealed the presence of important sesqueterpenoids and phenolics as the main bioactive phytoconstituents in the extracts. Sesqueterpenoids, such as turmerone, ar-turmerone, curlone, and atlantone, and phenols, such as guaiacol (2-Hydroxyanisole phenol, 2-methoxy), and ethyl ferulate/ethyl 4′-hydroxy-3′methoxycinnamate, were found in C. longa extracts. The protective role of C. longa in BuMECs against LPS-induced inflammation and oxidant insult might be due to the presence of bioactive compounds, such as terpenoid and phenolic compounds. However, we further propose the isolation of these phytoconstituents and their analysis using HPLC and NMR studies. Full article

Ten phenolic constituents, including three new macrocyclic glycosides (1–3), a new phenolic glycoside (5), a new biphenyl glycoside (6), and five known compounds (4, 7–10), were isolated from a 70% MeOH extract of the leaves of Heliciopsis terminalis by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-guided molecular networking. The chemical structures of new compounds 1–3, 5 and 6 were established based on comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS techniques. All isolated compounds (1–10) were evaluated for their stimulation of glucose uptake in differentiated 3T3-L1 adipocytes using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent glucose analog. Compounds 3, 6 and 8 showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Among them, compounds 3 and 6 activated the AMPK signaling pathway in differentiated C2C12 myoblasts. Full article

The efficient isolation process and understanding of lignin properties are essential to determine key features and insights for more effective lignin valorization as a renewable feedstock for the production of bio-based chemicals including wood adhesives. This study successfully used dilute acid precipitation to recover lignin from black liquor (BL) through a single-step and ethanol-fractionated-step, with a lignin recovery of ~35% and ~16%, respectively. The physical characteristics of lignin, i.e., its morphological structure, were evaluated by scanning electron microscopy (SEM). The chemical properties of the isolated lignin were characterized using comprehensive analytical techniques such as chemical composition, solubility test, morphological structure, Fourier-transform infrared spectroscopy (FTIR), ¹H and ¹³C Nuclear Magnetic Resonance (NMR), elucidation structure by pyrolysis-gas chromatography-mass spectroscopy (Py-GCMS), and gel permeation chromatography (GPC). The fingerprint analysis by FTIR detected the unique peaks corresponding to lignin, such as C=C and C-O in aromatic rings, but no significant differences in the fingerprint result between both lignin. The ¹H and ¹³C NMR showed unique signals related to functional groups in lignin molecules such as methoxy, aromatic protons, aldehyde, and carboxylic acid. The lower insoluble acid content of lignin derived from fractionated-step (69.94%) than single-step (77.45%) correlated to lignin yield, total phenolic content, solubility, thermal stability, and molecular distribution. It contradicted the syringyl/guaiacyl (S/G) units’ ratio where ethanol fractionation slightly increased syringyl unit content, increasing the S/G ratio. Hence, the fractionation step affected more rupture and pores on the lignin morphological surface than the ethanol-fractionated step. The interrelationships between these chemical and physicochemical as well as different isolation methods were investigated. The results obtained could enhance the wider industrial application of lignin in manufacturing wood-based composites with improved properties and lower environmental impact. Full article

(+)-Catechin—laccase oxidation dimeric standards were hemi-synthesized using laccase from Trametes versicolor in a water-ethanol solution at pH 3.6. Eight fractions corresponding to eight potential oxidation dimeric products were detected. The fractions profiles were compared with profiles obtained with two other oxidoreductases: polyphenoloxidase extracted from grapes and laccase from Botrytis cinerea. The profiles were very similar, although some minor differences suggested possible dissimilarities in the reactivity of these enzymes. Five fractions were then isolated and analyzed by 1D and 2D NMR spectroscopy. The addition of traces of cadmium nitrate in the samples solubilized in acetone-d₆ led to fully resolved NMR signals of phenolic protons, allowing the unambiguous structural determination of six reaction products, one of the fractions containing two enantiomers. These products can further be used as oxidation markers to investigate their presence and evolution in wine during winemaking and wine ageing. Full article

Oleuropein (OLEU) is the most distinguished phenolic compound found in olive fruit and the leaves of Olea europaea L., with several pharmacological properties, including anti-cancer actions. Adriamycin (ADR) is an anthracycline widely used as a chemotherapeutic agent, although it presents significant side effects. The aim of the present study was to investigate the effect of oleuropein alone (20 μg/mL) and in co-treatment with ADR (50 nM), in MG-63 human osteosarcoma cells. Therefore, cellular and molecular techniques, such as MTT assay, flow cytometry, real-time Polymerase Chain Reaction (PCR), western blot and Elisa method, as well as Nuclear Magnetic Resonance (NMR) spectroscopy, were applied to unveil changes in the signal transduction pathways involved in osteosarcoma cells survival. The observed alterations in gene, protein and metabolite levels denote that OLEU not only inhibits MG-63 cells proliferation and potentiates ADR’s cytotoxicity, but also exerts its action, at least in part, through the induction of autophagy. Full article

Bitterness often associated with whole wheat products may be related to phenolics in the bran. Cyclodextrins (CDs) are known to form inclusion complexes. The objective was to form inclusion complexes between β-CD and wheat phenolics. Pure phenolic acids (trans-ferulic acid (FA), caffeic acid (CA), and p-coumaric acid (CO)) and phenolic acids from wheat bran were used to investigate complex formation potential. Complexes were characterized by spectroscopy techniques, and a computational and molecular modeling study was carried out. The relative amount of complex formation between β-CD and wheat bran extract was CA > CO > FA. The phenolic compounds formed inclusion complexes with β-CDs by non-covalent bonds. The quantum-mechanical calculations supported the experimental results. The most stable complex was CO/β-CD complex. The ΔH value for CO/β-CD complex was −11.72 kcal/mol and was about 3 kcal/mol more stable than the other complexes. The QSPR model showed good correlation between binding energy and ¹H NMR shift for the H⁵ signal. This research shows that phenolics and β-CD inclusion complexes could be utilized to improve the perception of whole meal food products since inclusion complexes have the potential to mask the bitter flavor and enhance the stability of the phenolics in wheat bran. Full article