Correlations between Total Antioxidant Capacity, Polyphenol and Fatty Acid Content of Native Grape Seed and Pomace of Four Different Grape Varieties in Hungary

From Waste to Wealth: Exploring the Bioactive Potential of Wine By-Products-A Review

The present paper explores the biological potential of bioactive compounds present in wine industry wastes, highlighting their valorization to promote sustainability and circular economy. Wine by-products, such as grape pomace and vine shoots, contain a high concentration of polyphenols, flavonoids, anthocyanins and other phytochemicals with antioxidant, anti-inflammatory and anticarcinogenic properties. Both conventional extraction methods, such as solid-liquid extraction, and emerging technologies, including enzyme-assisted extraction, ultrasound-assisted extraction, supercritical fluid extraction, microwave-assisted extraction, pressurized liquid extraction, high-hydrostatic-pressure extraction, and deep natural solvent-assisted extraction (NaDES), are discussed. In addition, the preservation of polyphenolic extracts by microencapsulation, a key technique to improve the stability and bioavailability of bioactive compounds, is addressed. The combination of advanced extraction methods and innovative preservation techniques offers a promising perspective for the valorization of bioactive compounds from wine residues, driving sustainability and innovation in the industry.

Exploring the Phytochemical Composition and the Bioactive Properties of Malbec and Torrontés Wine Pomaces from the Calchaquíes Valleys (Argentina) for Their Sustainable Exploitation

Hydroalcoholic extracts from Malbec and Torrontés wine pomaces (Vitis vinifera L.) originating from the high-altitude vineyards of Argentina's Calchaquí Valleys were characterized. Total phenolics, hydroxycinnamic acids, orthodiphenols, anthocyanins, non-flavonoid phenolics, total flavonoids, flavones/flavonols, flavanones/dihydroflavonols, and tannins were quantified through spectrophotometric methods, with the Malbec extract exhibiting higher concentrations in most of phytochemical groups when compared to Torrontés. HPLC-DAD identified more than 30 phenolic compounds in both extracts. Malbec displayed superior antiradical activity (ABTS cation, nitric oxide, and superoxide anion radicals), reduction power (iron, copper, and phosphomolybdenum), hypochlorite scavenging, and iron chelating ability compared to Torrontés. The cytotoxicity assessments revealed that Torrontés affected the viability of HT29-MTX and Caco-2 colon cancer cells by 70% and 50%, respectively, at the highest tested concentration (1 mg/mL). At the same time, both extracts did not demonstrate acute toxicity in Artemia salina or in red blood cell assays at 500 µg/mL. Both extracts inhibited the lipoxygenase enzyme (IC50: 154.7 and 784.7 µg/mL for Malbec and Torrontés), with Malbec also reducing the tyrosinase activity (IC50: 89.9 µg/mL), and neither inhibited the xanthine oxidase. The substantial phenolic content and diverse biological activities in the Calchaquí Valleys' pomaces underline their potentialities to be valorized for pharmaceutical, cosmetic, and food industries.

How does maturity stage affect seeds metabolome via UPLC/MS based molecular networking and chemometrics and in relation to antioxidant effect? A case study in 4 major cereals and legumes

Legumes and cereals as staple food are typically consumed at mature stage, though also consumed at earlier stages. UPLC/MS based molecular networking and chemometrics were employed for the first time to address metabolome composition heterogeneity amongst seeds in the context of their maturity stages. The study included 4 major cereal and leguminous seeds of different species, and cultivars i.e., Triticum aestivum, Hordeum vulgare, Vicia faba and Cicer arietinum. 146 Metabolites from various classes were identified of which several are first time to be reported. Supervised OPLS model of all datasets revealed that sugars and oxylipids were dominant in mature and immature seeds, respectively. DPPH and FRAP assays were assessed for differential secondary metabolites' correlation. Results were attributed to flavonoids, oxylipids, and amino acids/peptides. Mature barley seeds possessed the strongest antioxidant activity among examined seeds. This study provides novel insights on seeds' maturation process in context to holistic metabolic changes.

Response Surface Optimization of Extraction Conditions for the Active Components with High Acetylcholinesterase Inhibitory Activity and Identification of Key Metabolites from Acer truncatum Seed Oil Residue

The State Council of China has called for the comprehensive development and utilization of Acer truncatum resources. However, research on one of its by-products, namely seed oil residue (ASR), from seed oil extraction is seriously insufficient, resulting in a waste of these precious resources. We aimed to optimize the conditions of ultrasound-assisted extraction (UAE) using a response surface methodology to obtain high acetylcholinesterase (AChE) inhibitory components from ASR and to tentatively identify the active metabolites in ASR using non-targeted metabolomics. Based on the results of the independent variables test, the interaction effects of three key extracting variables, including methanol concentration, ultrasonic time, and material-to-liquid ratio, were further investigated using the Box-Behnken design (BBD) to obtain prior active components with high AChE inhibitory activity. UPLC-QTOF-MS combined with a multivariate method was used to analyze the metabolites in ASR and investigate the causes of activity differences. Based on the current study, the optimal conditions for UAE were as follows: methanol concentration of 85.06%, ultrasonic time of 39.1 min, and material-to-liquid ratio of 1.06:10 (g/mL). Under these optimal conditions, the obtained extracts show strong inhibitions against AChE with half maximal inhibitory concentration (IC₅₀) values ranging from 0.375 to 0.459 µg/mL according to an Ellman's method evaluation. Furthermore, 55 metabolites were identified from the ASR extracted using methanol in different concentrations, and 9 biomarkers were subsequently identified as potential compounds responsible for the observed AChE inhibition. The active extracts have potential to be used for the development of functional foods with positive effects on Alzheimer's disease owing to their high AChE inhibition activity. Altogether, this study provides insights into promoting the comprehensive utilization of A. truncatum resources.

Antimicrobial Potential, Antioxidant Activity, and Phenolic Content of Grape Seed Extracts from Four Grape Varieties

The aim of this study was to evaluate the total phenolic content, composition, and antioxidant and antibacterial activities of four grape seed extracts (Cabernet Sauvignon, Marselan, Pinot Noir, and Tamyanka). The total phenolic content (TPC) and flavonoid, anthocyanin, procyanidin, ascorbic acid, DPPH, and ABTS antioxidant capacities of the grape seed extracts (GSEs) were determined. The extracts showed high TPC values (79.06-111.22 mg GAE/g). The individual components in the GSEs were determined using HPLC. High contents of catechin, epicatechin, and procyanidin B1 were found in the extracts. The antimicrobial activity of the obtained GSEs against Staphylococcus aureus, Bacillus cereus, and Escherichia coli was evaluated using the agar diffusion test and a test to determine the minimum inhibitory concentration (MIC). According to the effect on the growth of pathogens, the extracts were ranked in the following order: Pinot Noir > Marselan > Cabernet Sauvignon > Tamyanka. The tested bacteria showed high sensitivity to the extracts (MIC = 0.12-0.50 mg/mL). According to the MIC values, the bacteria were in the following order: S. aureus > B. cereus > E. coli. A correlation was found between the phenolic content of the GSEs and their antibacterial potential. The obtained results show that the studied GSEs have good potential as antioxidant and antimicrobial agents.

Evaluation of the Phytochemistry-Therapeutic Activity Relationship for Grape Seeds Oil

Seeds' abundant biologically active compounds make them a suitable primary platform for the production of natural extracts, innovative foods, medicines, and cosmetics. High levels of industrial and agricultural residues and byproducts are generated during the processing of grapes, although some parts can also be repurposed. This paper examines the phytochemical composition, manufacturing processes, and health-improving attributes of many varieties of grape oil derived using various extraction methods. Since the results are influenced by a range of factors, they are expressed differently among studies, and the researchers employ a variety of measuring units, making it difficult to convey the results. The primary topics covered in most papers are grape seed oil's lipophilic fatty acids, tocopherols, and phytosterols. In addition, new methods for extracting grape seed oil should therefore be designed; these methods must be affordable, energy-efficient, and environmentally friendly in order to increase the oil's quality by extracting bioactive components and thereby increasing its biological activity in order to become part of the overall management of multiple diseases.

Zinc Biofortification in Vitis vinifera: Implications for Quality and Wine Production

Nowadays, there is a growing concern about micronutrient deficits in food products, with agronomic biofortification being considered a mitigation strategy. In this context, as Zn is essential for growth and maintenance of human health, a workflow for the biofortification of grapes from the Vitis vinifera variety Fernão Pires, which contains this nutrient, was carried out considering the soil properties of the vineyard. Additionally, Zn accumulation in the tissues of the grapes and the implications for some quality parameters and on winemaking were assessed. Vines were sprayed three times with ZnO and ZnSO₄ at concentrations of 150, 450, and 900 g ha^-1 during the production cycle. Physiological data were obtained through chlorophyll a fluorescence data, to access the potential symptoms of toxicity. At harvest, treated grapes revealed significant increases of Zn concentration relative to the control, being more pronounced for ZnO and ZnSO₄ in the skin and seeds, respectively. After winemaking, an increase was also found regarding the control (i.e., 1.59-fold with ZnSO₄-450 g ha^-1). The contents of the sugars and fatty acids, as well as the colorimetric analyses, were also assessed, but significant variations were not found among treatments. In general, Zn biofortification increased with ZnO and ZnSO₄, without significantly affecting the physicochemical characteristics of grapes.

Polysaccharides in Selenium-Enriched Tea: Extraction Performance under Innovative Technologies and Antioxidant Activities

Pulsed electric fields (PEF) and ultrasonic-assisted extraction (UE) were applied to improve the extraction performance of selenium-enriched tea polysaccharides (Se-TPSs) in mild conditions. Two combined extraction processes were investigated: (1) PEF strength at 10 kV/cm followed by conventional extraction (CE) at 50 °C for 60 min and (2) PEF+UE (PEF strength at 10 kV/cm followed by UE at 400 W for 60 min). The optimal extraction yields, and energy consumption rates were obtained at 36.86% and 41.53% and 78.78 kJ/mg and 133.91 kJ/mg, respectively. The Se-TPSs were analyzed and characterized by GPC, UV, and FT-IR, which evidenced the structural stability of the Se-TPSs during the extraction processes. It was found that PEF and UE could reduce the particle size diameter of the Se-TPS extract, as well as the proportion of uronic acid. Moreover, PEF could increase the selenium content in the Se-TPS extract by 160.14% due to a lower extraction temperature compared to conventional extraction. The antioxidant activities of the Se-TPSs in vitro were investigated using OH, O2-, and ABTS+ scavenging experiments, as well as a total antioxidant ability evaluation. It was found that the antioxidant activity of the Se-TPSs obtained using PEF2+CE2 was relatively high due to the potential synergistic effect between the selenium and polysaccharides. Based on these results, we speculate that PEF2+CE2 was the best extraction process for the Se-TPSs. Furthermore, this research indicates the application of selenium-enriched tea for functional food production.

Hydrolysis of Edible Oils by Fungal Lipases: An Effective Tool to Produce Bioactive Extracts with Antioxidant and Antimicrobial Potential

Hydrolysis of olive, rapeseed, linseed, almond, peanut, grape seed and menhaden oils was performed with commercial lipases of Aspergillus niger, Rhizopus oryzae, Rhizopus niveus, Rhizomucor miehei and Candida rugosa. In chromogenic plate tests, olive, rapeseed, peanut and linseed oils degraded well even after 2 h of incubation, and the R. miehei, A. niger and R. oryzae lipases exhibited the highest overall action against the oils. Gas chromatography analysis of vegetable oils hydrolyzed by R. miehei lipase revealed about 1.1 to 38.4-fold increases in the concentrations of palmitic, stearic, oleic, linoleic and α-linolenic acids after the treatment, depending on the fatty acids and the oil. The major polyunsaturated fatty acids produced by R. miehei lipase treatment from menhaden oil were linoleic, α-linolenic, hexadecanedioic, eicosapentaenoic, docosapentaenoic and docosahexaenoic acids, with yields from 12.02 to 52.85 µg/mL reaction mixture. Folin-Ciocalteu and ferric reducing power assays demonstrated improved antioxidant capacity for most tested oils after the lipase treatment in relation to the concentrations of some fatty acids. Some lipase-treated and untreated samples of oils, at 1.25 mg/mL lipid concentration, inhibited the growth of food-contaminating bacteria. The lipid mixtures obtained can be reliable sources of extractable fatty acids with health benefits.

Pomace-Cassava as Antioxidant Bio-Based Coating Polymers for Cheeses

Fruit and vegetable-based materials, rich in phenolic pigments, and especially anthocyanins, have attracted attention as promising sources for bio-based antioxidant coating polymers, being a non-toxic, natural, ecofriendly, and green label solution to lower oxidation degradation in oil-water emulsion food, such as cheeses. However, could their pomaces also be used in such materials? This work has investigated the use of jabuticaba peels and red cabbage stir pomace extracts as antioxidant additives for cheese coating polymers. The antioxidant capacity of the jabuticaba-red cabbage pomace cassava-based polymer was evaluated in vitro (total phenolic, total anthocyanin content and DPPH scavenging %) and in vivo (by coating Minas Frescal cheeses and monitoring their peroxide index increase during a 9-day shelf life, at 10 °C). An in vitro characterization has indicated a high antioxidant capacity for both pomace extracts, with a higher capacity observed for the jabuticaba peels. In vivo investigations indicated that the pomace-starch coatings have protected cheeses up to 8.5 times against oxidation when compared to the control, with a synergistic protector effect among pomaces. Physical–chemical characterizations (pH, acidity, total solids, ash, total protein, fat content and syneresis) have indicated no coating interference on the cheese’s development.

Effects of Repeated Heating on Fatty Acid Composition of Plant-Based Cooking Oils

Several polyunsaturated fatty acids are considered to have beneficial health effects, while saturated fatty acids and industrial trans fatty acids (TFAs) are linked to negative health consequences. Given the increased formation of TFAs during heating, many studies already investigated compositional changes in oils after prolonged heating or at extremely high temperatures. In contrast, our aim was to measure changes in fatty acid composition and in some health-related indices in edible oils after short-time heating that resembles the conventional household use. Potatoes were fried in palm, rapeseed, soybean, sunflower and extra virgin olive oils at 180 °C for 5 min, and samples were collected from fresh oils and after 1, 5 and 10 consecutive heating sequences. Regardless of the type of oil, the highest linoleic acid and alpha-linolenic acid values were measured in the fresh samples, whereas significantly lower values were detected in almost all samples following the heating sequences. In contrast, the lowest levels of TFAs were detected in the fresh oils, while their values significantly increased in almost all samples during heating. Indices of atherogenicity and thrombogenicity were also significantly higher in these oils after heating. The present data indicate that prolonged or repeated heating of vegetable oils should be avoided; however, the type of oil has a greater effect on the changes of health-related indices than the number of heating sequences.

Predicted Shelf-Life, Thermodynamic Study and Antioxidant Capacity of Breadsticks Fortified with Grape Pomace Powders

Grape pomace (GP), is the main winemaking by-product and could represent a valuable functional food ingredient being a source of bioactive compounds, like polyphenols. Polyphenols prevent many non-communicable diseases and could contrast the oxidation reaction in foods. However, the high content in polyunsaturated fatty acid, the described pro-oxidant potential action of some polyphenols and the complex interactions with other components of matrices during food processing must be considered. Indeed, all these factors could promote oxidative reactions and require focused and specific assay. The aims of this study were to evaluate the effects of GP powder (GPP) addition (at 0%, 5% and 10% concentrations) in breadsticks formulations both on the antioxidant activity at room temperature during storage and on the shelf-life by the OXITEST predictive approach. GPP fortification increased the total polyphenols content and the antioxidant activities of breadsticks. FRAP reduced during the first two days of storage at room temperature, TPC increased during the 75 days, while ABTS showed a slight progressive decrease. However, GP negatively influenced OXITEST estimated shelf-life of breadsticks, incrementing the oxidation rate. In conclusion, even if GP fortification of breadsticks could improve the nutritional value of the products, the increased commercial perishability represents a drawback that must be considered.