Search Results (3,229)

The genus Oncosiphon (Asteraceae), consisting of aromatic herbs, is indigenous to southern Africa. Oncosiphon species have been documented in Khoi-San ethnobotany as herbal remedies for typhoid fever, pneumonia, and as diuretics. Research on the biological properties and comprehensive phytochemical profiling of these important Oncosiphon species is currently limited. This study was therefore undertaken to address the knowledge void in chemical profiling, through the application of various analytical techniques to analyse the volatile and non-volatile constituents of three South African Oncosiphon species. The aerial parts of Oncosiphon suffruticosus (n = 28), O. grandiflorus (n = 16), and O. africanus (n = 4) were collected from various locations in the Western Cape Province of South Africa. The stems and leaves (SL) were separated from the flowers (F) and analysed as distinct samples. The methanol: chloroform (1:1, v/v) extracts were prepared and analysed using ultra–high–performance liquid chromatography quadrupole time-of-flight time–of–flight mass spectrometry (UHPLC–QToF–MS) and a semi–automated high–performance thin–layer chromatography (HPTLC) system. Multivariate data analysis was performed on the UHPLC–QToF–MS data to determine interspecies chemical variation. Two-dimensional (2D) gas chromatography (GCxGC–ToF–MS) was used to determine the headspace volatile profiles of the intact aerial parts. The results show that the non-volatile profiles of the Oncosiphon species are characterised by amino acids, phenolic acids, flavonoids, sesquiterpene lactones, and fatty acid derivatives. The HPTLC profiles of O. grandiflorus and O. africanus are chemically more closely related, and O. suffruticosus has a distinct profile, which is supported by the chemometrics results of the flowers. The major headspace volatile compounds in Oncosiphon flowers are α-pinene, α-ocimene, eucalyptol, o-cymene, and artemisia alcohol, whereas the stems and leaves mainly consist of α-ocimene, eucalyptol, and yomogi alcohol. Full article

This study comprehensively characterised the volatile composition of hydrolates obtained as by-products of the hydrodistillation of orange, mandarin, and clementine peels. Enzymatic pretreatments using pectinase, cellulase, xylanase, or their mixture were applied in purified water or citrate buffer (pH 5) prior to Clevenger hydrodistillation, and volatile profiles were analysed by HS–SPME GC–MS. Across all citrus species, hydrolates were dominated by oxygenated monoterpenes and alcohols, with α-terpineol and linalool identified as the principal constituents. Statistical analysis suggested differences in hydrolate volatile composition following enzymatic pretreatment in citrate buffer with cellulase, xylanase, or their combination (p < 0.05); notably, α-terpineol content in mandarin hydrolates nearly doubled after these treatments. Enzyme-free reflux extraction in water also led to observable changes in volatile profiles (p < 0.05), highlighting the importance of including both untreated and enzyme-free controls when evaluating enzymatic effects. The study also illustrates the distinct distribution of dominant volatiles between hydrolates with prevailing α-terpineol. These findings demonstrate the potential of enzymatic hydrodistillation for the valorisation of citrus peel by-products by enabling modulation of hydrolate volatile composition and supporting more sustainable use of citrus processing residues. Full article

This work investigates the physicochemical characteristics of waste tire pyrolysis char (WTP-char) produced at 500 °C in an industrial-scale auger reactor. The study uniquely combines material profiling with environmental safety assessment, specifically targeting organic contaminants and polymer stabilizers, evaluating WTP-char’s potential for circular economy applications. The samples underwent comprehensive analysis, including GC-MS, TGA, SEM-EDS, TXRF, and BET surface area measurements. The results revealed a high volatile matter content (13 wt.%), attributed to the thermal inertia typical of industrial-scale units. The organic fraction was dominated by n-alkanes (48.3%) and a significant concentration (6.97%) of the stabilizer Tris(2,4-di-tert-butylphenyl) phosphate (bDtBPP), posing potential environmental risks due to its cytotoxicity. Polycyclic aromatic hydrocarbon (PAH) analysis showed a prevalence of high-molecular-weight (HMW) compounds (79.7%), indicating high chemical stability. Although the specific surface area was low (28.9 m²/g), suggesting the need for activation, the material exhibits potential as a low-cost semi-reinforcing filler or solid fuel. By moving beyond laboratory-scale experiments to real industrial production, this study establishes a practical framework for evaluating both the performance and environmental safety of waste tire pyrolysis char. Full article

With the increasing consumer demand for high-quality lamb, crossbreeding has become a key technology for improving the production performance and meat quality of sheep. To evaluate the meat quality advantages and characteristics of Suffolk (SFK) and Hu sheep (HH) and their F₁ crossbreds (SH), thirty-six 3-month-old male lambs of SFK (n = 12), HH (n = 12), and SH (n = 12) were selected and raised in individual pens under the same nutritional and management conditions. After standardized feeding until 6 months of age, the Longissimus dorsi muscle was collected to determine meat quality traits, amino acid and fatty acid profiles, and volatile flavor compounds. The results indicated that the L*, a* and b* values of the SH group were significantly lower than those of the parental breeds (p < 0.05), with tenderness being intermediate between the two parent breeds. Notably, drip loss and cooking loss were significantly lower in the SH group (p < 0.05), indicating superior water-holding capacity. In terms of amino acid profiles, the contents of non-essential amino acids (NEAAs) and sweet-tasting amino acids in the SH group were significantly higher than those of the parent breeds (p < 0.05), with the overall profile meeting the FAO/WHO ideal protein pattern. Analysis of fatty acid profiles revealed that the SH group had significantly lower total saturated fatty acids (SFAs) (p < 0.05) and significantly higher levels of functional fatty acids (such as CLA), resulting in a significantly higher UFAs (unsaturated fatty acids)/SFAs (saturated fatty acids) ratio (p < 0.05) and superior nutritional value of fat. Furthermore, 32 volatile flavor compounds were detected in the SH group; among them, key aroma-active compounds such as isoamyl formate, 3-methyl-1-butanol, and acetoin were significantly higher than in the parental breeds (p < 0.05), contributing to a unique flavor profile. Consequently, this study systematically reveals the advantages of Suffolk × Hu F₁ crossbreds in terms of meat quality, nutritional value, and flavor characteristics, providing fundamental data for the optimization of crossbreeding systems, breeding selection, and the quality improvement of sheep meat products. Full article

Improving meat quality using safe phytogenic feed additives is of practical interest in yellow-feathered broiler production. This study aimed to evaluate the effects of dietary Stevia rebaudiana Bertoni extract (SBE) supplementation on meat quality traits. A total of 510 one-day-old, female yellow-feathered broilers were randomly allocated to six dietary treatments (0, 50, 100, 200, 300, and 400 mg/kg SBE) for 63 days. Meat sensory attributes, routine physicochemical characteristics, amino acid and fatty acid composition, electronic-nose profiles, and total volatile basic nitrogen (TVB–N) during refrigerated storage were assessed. Overall, the results provide evidence that dietary SBE supplementation is associated with changes in multiple meat quality-related parameters, supporting further evaluation of SBE as a phytogenic feed additive in yellow-feathered broilers. Full article

Drying and storage conditions play a critical role in shaping the quality of aged citrus peel. This study investigated the effects of different processing strategies on the volatile composition, microstructure, and sensory characteristics of five-year-aged Citrus Reticulata ‘Chachi’ Peel (CRP). Four treatments were evaluated using SPME/GC–MS, GC–IMS, electronic nose analysis, sensory assessment, scanning electron microscopy (SEM), and multivariate statistical tools. GC–IMS identified 96 volatile compounds, demonstrating that aging combined with varied drying–storage conditions promoted the formation of diverse aroma-active substances. Terpenes and related compounds predominated, with the indoor-dried and warehouse-stored XH sample showing significantly higher concentrations of key terpenoids and sesquiterpenes, including α-terpineol, γ-muurolene, germacrene, β-selinenol, α-farnesene, and nerolidol. These compounds contributed to enhanced citrus, floral, fruity, and woody notes. Principal component analysis of electronic nose data (93.46% cumulative variance) clearly distinguished XH from other samples. Sensory results supported instrumental findings, indicating stronger fruity and sweet attributes in XH and C, while sun-dried samples exhibited more hay-like characteristics. SEM revealed better structural integrity in indoor-dried samples, potentially facilitating volatile retention. Overall, indoor drying and controlled storage improved aroma complexity and sensory quality, providing a scientific basis for optimized CRP processing. Full article

Driven by the growing demand for flavor diversification in the global craft beer market, conventional drum roasting for specialty malt faces limitations in time consumption and flavor retention. This study aimed to explore explosive puffing as a novel approach for specialty malt production. Base barley malt was treated via explosive puffing at 0.8 MPa to prepare puffed specialty malt, followed by comprehensive characterization of its physicochemical properties, volatile profile, and antioxidant activity, with brewing trials conducted at 15% grist substitution. Results showed that puffed malt reached a color of 183.15 EBC, with formation of roasted pyrazines and caramel-like furans, and a nearly 3-fold increase in total phenolic content and antioxidant capacity. At 15% addition, the puffed malt maintained wort free amino nitrogen and reducing sugar levels, while significantly enhancing beer color, roasted aroma, and antioxidant activity. These findings demonstrate that explosive puffing is a promising alternative to conventional roasting for producing specialty malt. Full article

Background/Objectives: This study aimed to investigate the phytochemical composition, antioxidant capacity, and anticancer potential of methanol and ethanol extracts of Lactarius deliciosus (L.) Gray in MCF-7 breast cancer cells, focusing on their effects on energy metabolism and related molecular mechanisms. Methods: In L. deliciosus samples, total antioxidant activity and total phenolic content were determined spectrophotometrically, while individual phenolics were classified by HPLC and volatile aromatic compounds (VOCs) were determined by GC-MS. The anticancer effects of L. deliciosus in MCF-7 breast cancer were determined using RT-qPCR with 46 different genes. Results: Phytochemical profiling via HPLC and GC–MS revealed a rich diversity of bioactive compounds, including significant levels of gallic acid (298.89 µg/g), vanillic acid (191.98 µg/g), and succinic acid (724.73 µg/g). The extracts exhibited robust antioxidant activity and dose-dependent cytotoxicity, reducing cell viability to as low as 5.60% after 72 h. Molecular analysis through Reactome pathway enrichment and expression profiling of 46 genes demonstrated that L. deliciosus drives cancer cells into a metabolic impasse by reversing the Warburg effect. Key findings include the significant downregulation of glycolytic genes like SLC2A1/GLUT1 (−12.34) and HK2 (−1.71), alongside the repression of mitochondrial TCA cycle regulators such as IDH1 (−17.81) and OGDH (−2.54). This metabolic collapse triggered G0/G1 phase cell cycle arrest and induced apoptosis. Conlusions: These results align with international benchmarks for Lactarius species while providing novel insights into the metabolic reprogramming mechanism. The results obtained in this study highlight that L. deliciosus emerges as a promising natural agent for therapeutic strategies targeting cancer bioenergetics. Full article

Polytrichadelphus purpureus is a bryophyte distributed in tropical and subtropical regions. It represents an underexploited source of bioactive metabolites. In this study, the volatile fraction (VF) obtained by steam distillation was analyzed by gas chromatography (GC-MS and GC-FID) on a DB-5ms capillary column, identifying 86 volatile compounds, representing the 97% of the volatile profile. Sesquiterpene hydrocarbons (23.6%), alcohols (15.6%), and alkanes (14.1%) were the major group compounds. Major components include (Z)-falcarinol (14%), hexacosane (4%), β-Curcumene (3%), and oleic acid (3%), among others. In addition, the volatile fraction exhibited moderate in vitro inhibitory activity against Gram-positive bacteria (E. faecium, S. aureus), fungus A. niger at concentrations of 250 µg/mL and 500 µg/mL, respectively, and E. faecalis and L. monocytogenes (250–500 µg/mL) and a weak inhibition of acetylcholinesterase (IC₅₀: 392 µg/mL). These effects were evaluated for the first time in this species. While they are within the range reported for other plant-derived volatile fraction, they do not, on their own, justify claims of therapeutic efficacy. This study primarily advances our understanding of the genus Polytrichadelphus, suggesting potential as a source of bioactive sesquiterpenes for future phytochemical screening. Full article

Repetitive temperature fluctuations during transportation and storage promote ice crystal formation in salmon flesh, leading to protein denaturation, lipid oxidation, and quality loss. Tuna skin, a major by-product of tuna processing, is a potential source of antifreeze peptides (AFPs) but remains underutilized. This study examined the cryoprotective effects of tuna skin-derived AFPs on salmon cubes subjected to repeated freeze–thaw cycles. Cubes treated with AFPs from three groups of protein hydrolysates prepared using trypsin, pepsin, or neutral protease were evaluated for texture, color, water holding capacity (WHC), volatile odor profiles, protein conformation, biochemical indices, and microstructure. AFP treatment improved textural properties, maintained color stability, and reduced thawing, cooking, and centrifugal losses. The neutral protease-treated group exhibited the optimal cryoprotective ability and it also limited aldehyde and sulfide accumulation, preserved the retention rate of α-helix structure at 49% which was higher than 39% in controls, and enhanced Ca²⁺-ATPase activity to 1.75 μmol Pi·mg⁻¹·h⁻¹ with a 45.8% increase compared to controls, and significantly inhibited protein and lipid oxidation. Microstructural analysis showed compact fibers and intact sarcolemma in the neutral protease-treated group samples, contrasting with severe disruption in controls. This study showed that tuna skin AFPs mitigate freeze–thaw damage in salmon cubes by stabilizing proteins and reducing oxidative deterioration, highlighting their potential as natural, healthy cryoprotectants for seafood preservation, meeting the growing demand of the food industry for clean-label, low-calorie preservation solutions, while advancing the circular economy of aquatic processing via the valorization of tuna skin by-products for high-value seafood applications. Full article

Blueberries (Vaccinium corymbosum L.) are widely appreciated for their flavor, bioactive compounds, and health promoting properties, yet cultivar-dependent differences in metabolic composition and postharvest stability remain incompletely understood. This study evaluated five commercial blueberry cultivars (‘Aurora’, ‘Chandler’, ‘Elliot’, ‘Legacy’, and ‘Liberty’) at harvest and after 15 days of cold storage (postharvest stage) (4 °C), assessing fruit color, size, firmness, primary metabolites, volatile organic compounds (VOCs), anthocyanins, phenolics, and antioxidant capacity. Cultivar-specific differences were observed in fruit morphology, sugar/acid balance, and biochemical composition: ‘Liberty’ and ‘Elliot’ accumulated higher monosaccharides and disaccharides, whereas ‘Aurora’ and ‘Chandler’ showed higher organic acids and amino acids. Volatile profiling at harvest revealed that ‘Liberty’ exhibited the richest aromatic profile, with elevated aldehydes, ketones, acids, phenols, alcohols, and esters. Postharvest storage caused minor changes in primary metabolites but altered anthocyanin content in a cultivar-dependent manner. Principal component analysis indicated that volatile compounds were the primary factors differentiating cultivars, while primary metabolites largely influenced sweetness–acidity balance. Overall, the results demonstrate that blueberry fruit quality is strongly cultivar-dependent, with cultivar-specific metabolic and volatile signatures shaping sensory and nutritional attributes, and provide valuable information for breeding, postharvest management, and cultivar selection to optimize flavor, bioactive content, and shelf-life. Full article

Bayberry (Morella rubra Lour.; syn. Myrica rubra (Lour.) Siebold & Zucc.) leaves are rich in bioactive compounds but remain underutilized. This study investigated the optimal harvest stage and processing methods to develop high-quality functional powder. We first compared three growth stages: red buds (RB), new leaves (NL), and old leaves (OL). RB exhibited the highest antioxidant capacity and unique volatile profile; however, NL was selected for processing optimization due to the balance between quality and biomass availability. Subsequently, NL was subjected to freeze-drying (FD), mechanical drying (MD), steaming followed by MD (S-MD), and shade drying (SD). Results showed that FD preserved the vibrant green color, glandular trichome structure, ascorbic acid, and fresh volatiles (monoterpenes). Conversely, thermal drying (MD and S-MD) disrupted cellular barriers, which facilitated the extraction of minerals and robust polyphenols like myricitrin, yielding the highest extraction of flavonoids and corresponding antioxidant activity, measured by hydrophilic oxygen radical absorbance capacity (H-ORAC), in hot water extracts than FD. SD significantly degraded quality due to prolonged enzymatic oxidation. While FD is ideal for preserving aesthetics and heat-sensitive nutrients, low-cost MD and S-MD are recommended for producing antioxidant-rich powders for functional food applications where extraction efficiency is prioritized. Full article

Cofactors are small molecules or ions that participate in enzymatic reactions as essential carriers of electrons, atoms, or functional groups, thereby governing cellular redox balance and energy metabolism. In the yeast Saccharomyces cerevisiae, the availability of cofactors such as NAD(H), NADP(H), CoA, and acetyl-CoA directly influences the flux through biosynthetic pathways leading to aroma-active compounds. Esters and higher alcohols are the two most important families of volatile flavor compounds in fermented alcoholic beverages. Their synthesis is intimately linked to the intracellular levels and ratios of these cofactors. This review summarizes recent progress in cofactor engineering strategies aimed at modulating the production of esters, higher alcohols, and 2,3-butanediol in S. cerevisiae. We discuss the underlying metabolic pathways, highlight key studies that manipulate cofactor pools to redirect carbon flux, and examine emerging tools (e.g., riboswitches, fine-tuned promoter systems) that enable precise cofactor balancing. Finally, we outline future challenges and opportunities for applying cofactor engineering to design yeast cell factories with tailored flavor profiles. Full article

Bee pollen is an extraordinary nutritional product of honeybees. Its valuable profile depends on the concentration of bioactive compounds, influenced by multiple factors, such as geographical origin and botanical species. Pollen samples produced by a single farm and collected during four different seasonal periods were first subjected to palynological analysis and then evaluated for their volatile profile and the content of selected nutraceutical compounds. The June sample, characterized by a high percentage of Castanea pollen, exhibited the higher concentration of soluble sugars, proteins, antioxidant molecules and minerals. The heatmap and hierarchical clustering confirmed a pronounced seasonal variability in bee pollen volatile composition, strongly linked to changes in floral availability. The greatest dissimilar volatilomic fingerprints are represented by samples collected in November (monofloral pollen of Hedera helix) and April (polyfloral pollen). The seasonal variability on the bioactive compounds, as well as in aromatic composition, seem to be linked to the different compositions of plant pollen, related to its botanical origin. This study expands current knowledge on the chemical characterization of bee pollen and supports the use of volatilome analysis as a complementary tool to palynological investigation for assessing botanical origin, quality, and the ecological and sensory value of this bee product. Full article

Strawberry aroma and flavor are key determinants of consumer acceptance and market value, yet their relationship with physico-chemical and functional traits remains complex and cultivar-dependent. This study aimed to characterize the volatile profile, quality parameters, antioxidant capacity, microbial load, and sensory attributes of three strawberry cultivars (‘Rossetta’, ‘Melissa’, and ‘Gioelita’) grown in soilless culture systems and harvested at the commercial ripening stage. ‘Melissa’ showed significantly higher total soluble solids (8.65 °Brix) than ‘Rossetta’ (7.78 °Brix) and ‘Gioelita’ (7.47 °Brix), while titratable acidity was highest in ‘Gioelita’ (4.97 mg CA/L). Regarding phytochemical traits, ‘Melissa’ exhibited the greatest total polyphenol, flavonoid, and antioxidant capacity values, followed by ‘Rossetta’ and ‘Gioelita’. Sixty-four volatile organic compounds (VOCs) were identified, semi-quantified, and combined with physico-chemical and sensory data related to odor and taste perception. Principal component analysis was applied to evaluate cultivar discrimination and identify the key discriminatory volatiles. The results revealed clear separation among cultivars based on their compositional and sensory profiles. ‘Rossetta’ was characterized by a higher abundance of esters, lactones, and mesifuran and received the highest sensory scores for sweetness and overall flavor, consistent with its elevated anthocyanin content. ‘Gioelita’ was associated with key esters contributing to strawberry flavor and with higher titratable acidity and perceived acidity. ‘Melissa’ showed a balanced volatile composition, higher antioxidant capacity, and greater phenolic content but also had higher microbial counts. Overall, the integration of chemical and sensory analyses provided useful insights into cultivar-specific quality traits relevant for breeding and production strategies. Full article