On-vine drying (passérillage) improves the quality of "Hutai No. 8" table grape wine: Focusing on phenolics, aromas, color and sensory attributes.

On-vine drying (passérillage) was employed for Hutai No.8 table grapes with different water loss rates and that are used for winemaking to alter the qualities of wine. Results showed that on-vine drying increased sugar content, thereby elevating alcohol and glycerol contents in the resulting wine. A moderate drying treatment (D2, 18 % water loss) produced wine with optimal red color characteristics. The D2 wine contained abundant individual phenolics such as caffeic acid, salicylic acid, resveratrol, p-coumaric acid, and proanthocyanidin B1, which exhibited strong positive correlations with color parameters (a⁎, C*ab and △E*ab). Similar trends were observed in aroma compounds, with ethyl acetate, ethyl caproate, diethyl succinate, geraniol, linalool, 4-terpinenol, α-terpineol, and ß-ionone contents showing significant increment in D2, aligning with enhanced sensory evaluations of wines. Thus, improvement of wine quality can be achieved through moderate on-vine drying (18 % water loss)，serving as a valuable reference for table grape winemaking.

Salinity Stress Ameliorates Pigments, Minerals, Polyphenolic Profiles, and Antiradical Capacity in Lalshak.

Previous studies have shown that salinity eustress enhances the nutritional and bioactive compounds and antiradical capacity (ARC) of vegetables and increases the food values for nourishing human diets. Amaranth is a salinity-resistant, rapidly grown C4 leafy vegetable with diverse variability and usage. It has a high possibility to enhance nutritional and bioactive compounds and ARC by the application of salinity eustress. Hence, the present study aimed to evaluate the effects of sodium chloride stress response in a selected Lalshak (A. gangeticus) genotype on minerals, ascorbic acid (AsA), Folin−Ciocalteu reducing capacity, beta-carotene (BC), total flavonoids (TF), pigments, polyphenolic profiles, and ARC. A high-yield, high-ARC genotype (LS6) was grown under conditions of 0, 25, 50, and 100 mM sodium chloride in four replicates following a block design with complete randomization. We recognized nine copious polyphenolic compounds in this accession for the first time. Minerals, Folin−Ciocalteu reducing capacity, AsA, BC, pigments, polyphenolic profiles, and ARC of Lalshak were augmented progressively in the order: 0 < 25 < 50 < 100 mM sodium chloride. At 50 mM and 100 mM salt concentrations, minerals, AsA, Folin−Ciocalteu reducing capacity, BC, TF, pigments, polyphenolic profiles, and ARC of Lalshak were much greater than those of the control. Lalshak could be used as valuable food for human diets as a potent antioxidant. Sodium chloride-enriched Lalshak provided outstanding quality to the final product in terms of minerals, AsA, Folin−Ciocalteu reducing capacity, BC, TF, pigments, polyphenolic profiles, and ARC. We can cultivate it as a promising alternative crop in salinity-prone areas of the world.

Exploring Antioxidant Activity, Organic Acid, and Phenolic Composition in Strawberry Tree Fruits (Arbutus unedo L.) Growing in Morocco.

This study aimed to explore the main biochemical components and the antioxidant capacity of five strawberry tree fruits using three antioxidant essays within the ecotypic comparison scheme, to find out the most valuable fruit presenting disease-preventing properties. Total phenols, total flavonoids, total anthocyanins, antioxidant activity (DPPH, ABTS, and ß-Carotene bleaching assays), pH, titratable acidity, soluble solids, and moisture content were investigated in five strawberry tree genotypes belonging to several areas in Morocco. Phenolic compounds were also identified using high performance chromatography (HPLC), with a diode array detector (DAD). High significant differences (p ˂ 0.05) were revealed among the examined genotypes regarding their total phenols (25.37-39.06 mg gallic acid equivalents (GAE)/g Dry weight (DW), total flavonoids (3.30-7.07 mg RE/g Dry weight (DW), total anthocyanins (0.15-0.64 mg cya-3-glu/100g Dry weight (DW), pH (2.44-3.92), titratable acidity (0.65-1.01 g malic acid/100g Fresh weight (FW), and soluble solids (14.83-18.53%). The average radical scavenging capacity, assessed using three methods, exhibited the following concentration ranges: 3.33-21.08, 2.25-19.58, and 1.08-13 mg Ascorbic Equivalent (AAE/g Dry weight(DW) for the DPPH scavenging test, ABTS, and ß-carotene bleaching, respectively. Seventeen phenolic compounds were identified in sampled cultivars. Gallocatechol and catechin were found to be the major phenolic compounds. The correlation matrix revealed significant correlations among investigated variables, particularly ABTS and DPPH. The principal component analysis showed that the first three components formed 90.25% of the total variance. The following variables: chlorogenic acid, ellagic acid derivative, ellagic acid, rutin, and cyanidin-30.5-diglucoside, were the most involved in the total variance. The results revealed highly promising physico-biochemical profiles within the studied strawberry tree genotypes.

Changes in polyphenol composition and bioactivity of the native Chilean white strawberry (Fragaria chiloensis spp. chiloensis f. chiloensis) after in vitro gastrointestinal digestion.

The Chilean white strawberry (Fragaria chiloensis spp. chiloensis f. chiloensis) is a semi-domesticated strawberry with high polyphenol content and antioxidant activity occurring in southern Chile. The aim of this work was to compare the composition and bioactivity of the polyphenol-enriched fruit extract (PEE) before and after simulated gastrointestinal digestion (GID). Results show a decrease by >50% in the total phenolic (TP) content at the end of the GID, compared to the non-digested PEE. A reduction in the antioxidant capacity of the PEEs was observed after GID by means of DPPH, FRAP, TEAC and anion superoxide assays. After simulated GID the PEE significantly inhibited α-glucosidase with an IC50 value of 3.13µg/mL. The inhibition of pancreatic lipase was reduced by 95% after GID. All the PEEs did not show inhibitory effect towards α-amylase throughout the GID. In the same way, the PEEs did not significantly protect human gastric adenocarcinoma (AGS) cells against H2O2-induced stress. Thirty eight compounds were tentatively identified in the non-digested PEE. The compounds that were more affected by the simulated GID were simple phenolics. After the GID, only 33 and 25 compounds were detected, in the gastric and intestinal steps, respectively. These results evidence the changes elicited by GID on the bioactivity and polyphenolic composition of the white strawberry.

Colonic fermentation of polyphenols from Chilean currants (Ribes spp.) and its effect on antioxidant capacity and metabolic syndrome-associated enzymes.

The Chilean wild currants Ribes magellanicum and R. punctatum are a good source of polyphenols. Polyphenolic-enriched extracts (PEEs) from both species were submitted to in vitro colonic fermentation to assess the changes in phenolic composition, antioxidant capacity and inhibition of metabolic syndrome-associated enzymes. The phenolic profiles of the fermented samples showed significant changes after 24 h incubation. Nine metabolites, derived from the microbial fermentation, were tentatively identified, including dihydrocaffeic acid, dihydrocaffeoyl-, dihydroferuloylquinic acid, 1-(3,4-dihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl)propan-2-ol (3,4-diHPP-2-ol), among others. The content of anthocyanins and hydroxycinnamic acids was most affected by simulated colonic conditions, with a loss of 71-92% and 90-100% after 24 h incubation, respectively. The highest antioxidant capacity values (ORAC) were reached after 8 h incubation. The inhibitory activity against the enzyme α-glucosidase was maintained after the fermentation process. Our results show that simulated colonic fermentation exerts significant changes on the polyphenolic composition of these berries, modifying their health-promoting properties.

Qualitative and quantitative changes in polyphenol composition and bioactivity of Ribes magellanicum and R. punctatum after in vitro gastrointestinal digestion.

The wild Chilean currants Ribes magellanicum and R. punctatum are a good source of polyphenolic compounds. The effect of simulated gastrointestinal digestion (GID) on phenolic content, composition and antioxidant capacity was determined. The inhibitory activity of the non-digested and digested samples towards metabolic syndrome-associated enzymes (α-amylase, α-glucosidase and lipase) was evaluated. The total phenolic (TP) and flavonoid contents (TF) decreased by about 50% at the end of the in vitro GID. Main anthocyanins and hydroxycinnamic acids were strongly affected by this process, with a loss of about 80%. A decrease in the antioxidant activity was observed throughout the digestion steps, which was correlated with the reduction in the TP and TF content. After the in vitro GID of the samples, only the inhibition of α-glucosidase was preserved. Our results show that the simulated GID modified the health-promoting properties of the studied currants.