Search Results (3,481)

The herbal tea industry has experienced substantial growth, particularly regarding green tea (Camellia sinensis). In the manufacturing of filter tea, fine herbal dust is generated as a residual by-product during grinding and sieving and is typically discarded as waste. This study aims to explore the application of ultrasound-assisted extraction (UAE) for secondary valorisation of green tea herbal dust by investigating the effects of various parameters on extraction efficiency. Antiradical activity of UAE extracts was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and the total phenolic content (TPC) was measured using Folin–Ciocalteu’s assay. Furthermore, selected phenolics were quantified by HPLC and qualitatively characterised by liquid chromatography coupled with electrospray ionisation and quadrupole time-of-flight tandem mass spectrometry (LC-ESI-QToF-MS/MS). The results demonstrate that UAE parameters have a pronounced influence on the antioxidant activity, TPC, and individual polyphenolic profile of green tea herbal dust extracts. Ethanol–water mixtures at a ratio of around 40–60%, as well as moderate impulse regimes (around 60%) and extraction times (around 10 min), were the most suitable for extracting green tea polyphenols. Epigallocatechin gallate was the predominant phenolic component in most extracts, alongside epicatechin, epigallocatechin, catechin, and gallic acid. The findings highlight the UAE technique as a robust, green, and scalable method for valorising green tea by-products, thereby facilitating the development of high-value natural extracts for applications in the food, pharmaceutical, and cosmetic industries. Full article

Plant-derived antimicrobial compounds are emerging as promising alternatives to synthetic preservatives in the food industry due to their efficacy against a broad spectrum of pathogenic and spoilage microorganisms, as well as their consumer acceptance. This review critically examines the main classes of bioactive phytochemicals, including essential oils, polyphenols, alkaloids, terpenoids, and saponins, comparing their relative antimicrobial effectiveness and highlighting representative examples. Notably, essential oils rich in thymol or carvacrol have shown strong inhibitory activity against Listeria monocytogenes and Salmonella spp., while polyphenols and alkaloids exhibit moderate to strong activity depending on concentration and food matrix. Their mechanisms of action include cell membrane disruption, inhibition of key enzymes, and interference with DNA or protein synthesis. Applications in food systems (i.e., incorporation into coatings, emulsions, or controlled-release formulations) demonstrate potential for extending shelf life and enhancing safety. However, practical implementation is challenged by matrix-dependent efficacy, compound stability, sensory impact, and regulatory and toxicological considerations. By synthesizing current knowledge, identifying the most promising compound classes, and highlighting key limitations, this review provides a critical framework to guide future research and the development of effective, sustainable natural preservatives in the food industry. Full article

Diet plays a fundamental role in maintaining human health, which has intensified scientific interest in bioactive food constituents and contributed to the development of functional foods. Polyphenols, one of the most important groups of plant secondary metabolites, are valued for their strong antioxidant properties and potential health benefits. Species belonging to the Rosaceae family, including Rosa, Crataegus, and Pyracantha, are recognized as promising sources of phenolic compounds, although their chemical profiles and antioxidant potential remain insufficiently characterized. The aim of this study was to quantitatively assess selected phenolic compounds in extracts obtained from ripe fruits of selected Rosaceae species and cultivars. The extracts were prepared using ultrasound-assisted solvent extraction, pressurized liquid extraction, and matrix solid-phase dispersion. The resulting samples were subsequently subjected to comprehensive analyses of their chemical composition and antioxidant capacity. These extraction techniques differ substantially in their operational principles and process parameters; notably, ultrasound-assisted solvent extraction and pressurized liquid extraction require more complex and tightly controlled conditions, whereas matrix solid-phase dispersion constitutes a comparatively simpler and less parameter-dependent approach. The results revealed distinct phenolic profiles among the examined species and confirmed the presence of compounds exhibiting strong antioxidant activity. Collectively, these findings broaden current knowledge of the phytochemical diversity present in Rosaceae fruits and underscore their potential as natural sources of bioactive constituents relevant to the development and formulation of functional food products. Full article

The integration of bioactive natural compounds into dental materials has gained increasing attention as a strategy to improve biological functionality while maintaining material performance. This narrative review aims to synthesize current evidence regarding the main classes of natural compounds investigated in dental materials, their incorporation methods, and their influence on material properties. A literature-based narrative approach was conducted using major scientific databases, including PubMed, Scopus, and Web of Science, focusing on studies addressing natural compound incorporation into restorative, prosthetic, adhesive, cementitious, and hydrogel-based dental materials. The reviewed literature indicates that polyphenols, polysaccharides, proteins and peptides, terpenoids, and microbial- and marine-derived compounds have been incorporated using bulk modification, surface functionalization, coating systems, and hybrid material architectures. While these compounds may provide antimicrobial, antioxidant, and bioactive properties, they may also influence mechanical behavior, physicochemical stability, optical characteristics, surface properties, and release behavior, depending on compound chemistry, concentration, and incorporation strategy. The available evidence highlights the need for a balanced approach that considers both biological activity and material performance, as well as the importance of stability, standardization, and long-term clinical performance when integrating natural bioactive compounds into dental materials. Full article

Bioactive polyphenols are increasingly recognized as modulators of multiple biological processes relevant to human health and disease. Among these compounds, genistein, a soy-derived isoflavone, and butein, a naturally occurring chalcone, have been investigated for their anticancer, anti-inflammatory, and metabolic regulatory activities, primarily in in vitro and preclinical experimental models. Despite their distinct chemical structures, available evidence indicates that genistein and butein can influence key molecular pathways involved in cell survival, energy metabolism, and programmed cell death. Experimental studies have shown that these compounds may modulate PI3K/Akt and MAPK/ERK signaling, alter glycolytic and mitochondrial metabolism, and induce apoptotic responses through caspase activation and poly(ADP-ribose) polymerase cleavage. This review provides a comprehensive overview of the chemical characteristics, bioavailability, and proposed molecular mechanisms of action of genistein and butein, with a particular focus on their potentially convergent roles in metabolic reprogramming and apoptotic signaling networks. In addition, we discuss the conceptual basis for combination approaches involving these compounds, emphasizing systems-level pathway modulation rather than definitive pharmacological synergy. Importantly, many of the reported biological effects have been observed under experimental conditions using concentrations that may exceed physiologically achievable concentrations, thereby limiting direct extrapolation to clinical settings. Furthermore, the current evidence base is constrained by limited in vivo validation and a lack of robust clinical data, particularly for butein. Future studies are required to better define pharmacokinetic properties, physiological relevance, and context-dependent biological effects, thereby providing a more rigorous framework for future evaluation of the translational potential of genistein and butein. Full article

Sunflower oil is particularly prone to thermo-oxidative degradation due to its high content of polyunsaturated fatty acids, especially under high-temperature conditions. This study investigated the oxidative stability of sunflower oil heated at 180 °C for 4 and 8 h, focusing on the protective effect of silibinin oleate (SIL-O), a lipophilic polyphenolic derivative, compared to the synthetic antioxidant butylated hydroxytoluene (BHT). Oxidative changes were evaluated through peroxide value (PV), p-anisidine value (p-AV), and total oxidation value (TOTOX), while structural alterations were monitored using FTIR spectroscopy. Additionally, fatty acid composition was analyzed by GC-MS to assess compositional changes associated with oxidation. Thermal treatment led to increases in PV, p-AV, and TOTOX, indicating progressive oxidation, alongside a decrease in unsaturated fatty acids. FTIR analysis revealed characteristic changes, including a reduction in the unsaturation band (~3008 cm⁻¹), modifications in the ester carbonyl region (~1743 cm⁻¹), and the emergence of bands associated with cis–trans isomerization (~968–970 cm⁻¹). Strong correlations were observed between fatty acid degradation, FTIR indices, and oxidation parameters. Compared to the control, SIL-O inhibited oxidation in a dose-dependent manner. At 300 ppm, it outperformed BHT, demonstrating its potential as a natural antioxidant for enhancing the stability of sunflower oil during high-temperature processing. Full article

Breast cancer remains a major global health challenge, requiring novel therapeutic strategies that can overcome drug resistance and improve treatment efficacy. This study investigates the synergistic antitumor effects of etoposide, a conventional chemotherapeutic agent, and resveratrol, a natural polyphenol with anticancer properties, in human breast cancer cell lines, with particular focus on their ability to activate the parthanatos cell death pathway. Using MCF-7 (estrogen receptor-positive) and MDA-MB-231 (triple-negative) breast cancer cells, we assessed cell viability via MTT assays and evaluated parthanatos activation through multiple complementary approaches including AIF translocation determined by subcellular fractionation, NAD+ depletion measurement, and gene expression analysis. Synergy was quantified using the Chou–Talalay method across multiple effect levels (ED50, ED75, ED90). To establish causality, Olaparib PARP inhibitor experiments were performed to confirm that PARP-1 hyperactivation is essential for the observed cytotoxic effects. The results demonstrated that the etoposide–resveratrol combination significantly enhanced cell death and inhibited proliferation compared to single-agent treatments, with combination index (CI) values indicating strong synergism (CI = 0.62–0.75 for MCF-7; CI = 0.58–0.71 for MDA-MB-231). This synergy was associated with robust parthanatos activation, evidenced by increased PARP-1 expression, AIF nuclear translocation confirmed by subcellular fractionation, and significant NAD+ depletion. Critically, Olaparib pre-treatment (3 µM) significantly rescued cells from combination-induced death, restored NAD+ levels to near-control values, and prevented AIF translocation, establishing a causal link between PARP-1 hyperactivation and parthanatos-mediated cytotoxicity. The combination also induced significant DNA fragmentation, elevated oxidative stress, and cell death with morphological features consistent with parthanatos, while caspase activity remained low, confirming caspase-independent cell death. These findings suggest that targeting parthanatos with etoposide and resveratrol could offer a promising therapeutic strategy for breast cancer, potentially overcoming resistance and improving efficacy. Further in vivo studies and clinical investigations are needed to validate these results and explore translational applications. Full article

Underutilized plant by-products are an overlooked source of natural extracts that contain antioxidant bioactive compounds and therapeutic potential. Oxidative stress significantly contributes to the development of various chronic diseases. In this context, natural extracts rich in bioactive compounds derived from underutilized plant by-products emerge as promising options for developing antioxidant-based therapies that target oxidative stress-related molecular pathways involved in the pathogenesis of chronic disease. The valorization of by-products through the recovery of antioxidant-rich extracts is particularly appealing, as non-edible plant parts often contain higher levels of bioactive compounds than their edible counterparts. This review provides a comprehensive overview of antioxidant natural extracts and their major bioactive components, including polyphenols (particularly flavonoids and phenolic acids), terpenoids, alkaloids, and other redox-active compounds. Full article

Background/Objectives: Obesity represents a critical risk factor for various chronic illnesses and metabolic dysfunctions, underscoring the urgency of identifying safe, food-based interventions to curb fat over-accumulation. Mesona procumbens Hemsl. (Hsian-tsao) is a traditional Chinese herb known for its antioxidant and health-promoting properties; however, it remains unclear how its phenolic acid profiles contribute to anti-obesity activity. This research explored the anti-adipogenic potential of various Hsian-tsao ethanol extracts, focusing on how their phenolic profiles influence lipid suppression in 3T3-L1 adipocytes. Methods: Ethanol extracts prepared using different ethanol concentrations were analyzed for total polyphenol content, antioxidant capacity, and phenolic acid profiles. Adipocytes were exposed to 0, 100, and 250 μg/mL of Hsian-tsao ethanol extract for 48 h duration to monitor changes in cell count and intracellular triglyceride levels. Results: Among all fractions, the 40% ethanol extract (40EEHT) possessed the most robust antioxidant capacity and highest polyphenol content, specifically showing enriched levels of caffeic acid, p-coumaric acid, and total phenolic acids. Notably, while 40EEHT influenced cell density at certain concentrations, it significantly and specifically reduced intracellular triglyceride content, indicating a potent inhibitory effect on lipid storage independent of changes in cell number. Comparative analysis using phenolic acid standards revealed that caffeic acid exerted the strongest inhibitory effect on lipid accumulation, suggesting that it is a key contributor to the anti-adipogenic activity of 40EEHT. Conclusions: Collectively, these findings demonstrate that phenolic acid profiles, particularly caffeic acid enrichment, critically contribute to the potential anti-adipogenic effects of specific ethanol extracts of M. procumbens. Therefore, Hsian-tsao ethanol extracts represent a promising natural source for the development of functional ingredients targeting obesity and related metabolic disorders. Full article

Oxidative stress is one of the major contributors to DNA damage and genomic instability, emphasizing the importance of identifying natural compounds with antioxidant genoprotective potential. Cedrus atlantica essential oil (EO) has been widely reported to possess antioxidant properties and potential genoprotective effects due to the presence of a cohort of antioxidant compounds, including polyphenols and terpenes. Nevertheless, its effects on DNA integrity remain poorly understood. The present study aimed to evaluate the genotoxic and antigenotoxic effects of C. atlantica EO in human peripheral blood mononuclear cells (PBMCs) using the alkaline Comet assay. PBMCs were exposed to increasing concentrations of the EO (0.2–3% w/v) under basal conditions and in the presence of hydrogen peroxide (H₂O₂, 25 µM) as an oxidative DNA-damaging agent. Genetic damage was quantified by visual score, and arbitrary units were converted into a percentage of DNA in the comet tail. The EO was characterized by gas chromatography–mass spectrometry. The results showed that C. atlantica EO did not induce detectable genotoxic effects under the experimental conditions and within the tested concentration range (0.2–3% w/v). H₂O₂ exposure markedly increased DNA strand breaks, whereas co-treatment with the EO significantly attenuated H₂O₂-induced oxidative DNA damage, particularly at intermediate concentrations. The chemical characterization analysis revealed a sesquiterpene-rich profile dominated by cedrene- and himachalene-type compounds. Overall, these findings indicate that C. atlantica EO exerts antigenotoxic effects against oxidative DNA damage, supporting its genoprotective potential in moderate concentrations. Full article

Flammulina velutipes (Golden Needle Mushroom, F. velutipes) undergoes rapid postharvest deterioration characterized by browning and decay. Drying effectively extends its shelf life and processing window. This study systematically compared the quality attributes and metabolic profiles of F. velutipes subjected to different treatments: fresh F. velutipes as the control group (CK), hot-air drying (HAD), vacuum freeze drying (VFD), and natural air drying (NAD), to elucidate the underlying mechanisms of drying-induced changes. In appearance, VFD samples were uniformly bright with shape well maintained, while HAD and NAD were brownish yellow with significantly reduced volume. In terms of antioxidant capacity, VFD demonstrated the highest level, followed by HAD. A total of 2645 metabolites were identified in dried F. velutipes via metabolomics (positive/negative ion modes), primarily comprising lipids, terpenoids, polyphenols, amino acids, carbohydrates, and steroids. In contrast to VFD, both HAD and NAD showed reduced levels of certain metabolites. VFD treatment yielded the richest profile of differential metabolites in F. velutipes. These results position VFD as the superior method for preserving the quality and metabolic integrity in F. velutipes. This comparative study serves as a practical reference for selecting the most suitable drying method in the F. velutipes industry and enhances our understanding of the metabolic responses to dehydration stress. Full article

Consumer preference for clean-label products is driving interest in natural antioxidants and antimicrobials that can replace synthetic preservatives. Ziziphus mauritiana (sidr), a resilient desert tree native to the arid Gulf region, has being tested as a multifunctional bio-preservative. This study evaluated the extraction yield, total phenolic content (TPC), total flavonoid content (TFC), antioxidant and antimicrobial activities, and poultry meat-preserving potential of Z. mauritiana. Methanol and ethanol produced the highest extract recoveries, with bark exhibiting the maximum extraction yield of up to 10.7 mg/100 g. Fruits demonstrated the highest total phenolic content (TPC) of around 175 mg gallic acid equivalents per gram (GAE/g) and total flavonoid content (TFC) of around 7.4 mg catechin equivalents per gram (CE/g), followed by leaves and bark. The antioxidant activity was significantly correlated with the concentration of phenolic compounds in the fruit extracts, which exhibited DPPH inhibition exceeding 60% in the majority of instances. The RP-HPLC investigation revealed a diverse polyphenolic profile, predominantly featuring gallic acid (up to 8.77 mg/g in leaves), catechin (6.30 mg/g in fruits), catechol, and caffeic acid. Leaf extracts showed 24 mm inhibitory zones against E. coli and Y. enterocolitica, while bark and fruit were not very effective. Adding ethanolic leaf extract (0–1%) to chicken breast meat reduced microbial degradation during chilled storage at 4 °C. At day 15, total aerobic counts reached only 5.34 log CFU/g with 1% extract compared with 8.53 log CFU/g in the control. Similar suppression was found for yeasts and molds, while challenge tests showed >3-log reductions in C. jejuni and Salmonella senftenberg. Sensory evaluation confirmed no detrimental effects on color, odor, flavor, or texture. Overall, Z. mauritiana was a valuable, renewable source of phenolic antioxidants and antimicrobial agents and showed strong promise as a natural preservative capable of improving the safety and shelf life of poultry meat in clean-label applications. Full article

Dietary phytogenic additives and microalgae are increasingly investigated as natural alternatives to antibiotic growth promoters in rabbit production due to their potential effects on gut health and nutrient utilisation. This study evaluated the nutraceutical potential of Chlorella vulgaris and Laurus nobilis as plant-based additives for growing New Zealand White rabbits. A 45-day feeding trial was conducted using control and experimental diets enriched with 0.1% Chlorella and 0.1% Laurus. Productive performance, nutrient digestibility, blood biochemistry and faecal composition were monitored, and polyphenolic compounds were analysed in feed, blood, faeces and caecal microbiota using HPLC-DAD. Final body weight (3097 vs. 2909 g) and feed intake (142.7 vs. 145.0 g day⁻¹) did not differ significantly between treatments. However, crude protein digestibility was significantly lower in the supplemented group than in the control group (54.39–47.79% vs. 63.73–62.33%; p < 0.05). Faecal chemical composition differed significantly between groups, particularly for dry matter, which was higher in the supplemented group across sampling times. Polyphenols detected across biological matrices confirmed the bioavailability of selected phytochemicals, with ferulic acid showing the highest stability. Correlation analysis indicated shared metabolic or absorptive pathways among several compounds. Overall, low-dose supplementation with C. vulgaris and L. nobilis appears safe and may support improved digestive physiology and nutrient utilisation without compromising rabbit health. Further research with larger sample sizes and detailed microbiome profiling is needed to clarify metabolic interactions and long-term effects of these nutraceutical strategies. Full article

Curcumin, a natural polyphenol derived from Curcuma longa, is widely recognized for its therapeutic properties. However, its clinical utility is limited because of poor solubility, rapid degradation and hence low bioavailability. To overcome these issues, nanoformulation approaches, especially PEGylated liposomes, have been explored as advanced delivery systems. PEGylation, which involves attaching polyethylene glycol (PEG) to the liposomal surface, enhances circulation time by creating a steric shield that reduces protein interactions and clearance by the mononuclear phagocyte system (MPS). However, PEG can alter lipid membrane properties, which may in turn affect curcumin’s solubility and distribution within the liposomal bilayer, ultimately reducing its loading efficiency. To ensure that PEG-modified liposomes can be effectively loaded with curcumin, we investigated curcumin–membrane interactions in saturated (DMPC) and unsaturated (POPC) liposomes, both in the presence and absence of PEG. Based on dissociation constants (K_d) obtained from fluorescence spectroscopy measurements, we found that PEGylated DMPC liposomes exhibit the strongest binding affinity for curcumin. Fluorescence quenching experiments showed that curcumin adopts a transbilayer orientation in all membranes examined. Curcumin’s location within PEGylated and non-PEGylated liposomal membranes was further confirmed by examining its effects on membrane properties, including fluidity, polarity, and oxygen transport. These effects were investigated using electron paramagnetic resonance (EPR) spectroscopy with spin labels. The results indicate that PEG does not impose major changes on membrane properties. Curcumin, however, was found to reinforce the liposomal membranes, increase their polarity, and reduce oxygen availability. Overall, the findings suggest that liposomes, particularly those composed of PEGylated DMPC, are effective vehicles for curcumin delivery. Full article

Food by-products have gained importance as valuable sources of bioactive compounds and structural lipids, with potential applications in food packaging. These residues, such as fruit peels, seeds, and fish skin, contain polymers and natural compounds like polyphenols, carotenoids, tocopherols, and phospholipids, which possess antioxidant and antimicrobial properties highly relevant for food preservation. However, the direct incorporation of these compounds is limited by their sensitivity to environmental factors such as light, oxygen, and pH. Liposomal encapsulation has emerged as a promising strategy to overcome these challenges, providing protection, controlled release, and increased bioavailability of both hydrophilic and lipophilic bioactives. The formulation of liposomes using lipids recovered from food industry by-products introduces an additional sustainability component, in line with the principles of the circular economy. Combining liposomes with other advanced preservation technologies, such as edible coatings and films, electrospinning fibers, and cyclodextrin inclusion complexes, is a promising alternative for extending the shelf-life and safety of food products, as well as for the development of functional foods. This review discusses the latest advances in liposome formulations with food by-products and their combination with other technologies to enhance their effectiveness in food preservation. Full article