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Phenolics were extracted from grape peels, and the compounds of grape peel phenolics (GPP) were identified by LC-MS/MS. From a perspective of dietary nutrition, this study aimed to evaluate the effect of GPP on lipid accumulation in sodium palmitate (PA)-treated HepG2 cells, and further to explore its mechanisms. HepG2 cells were induced by 0.4 mmol/L PA as an in vitro model of lipid accumulation. The results showed that GPP could significantly reduce the TG level and ROS production in PA-treated HepG2 cells. RT-qPCR and Western blotting analysis indicated that GPP supplementation can downregulate the mRNA and protein expression of lipogenesis factors and upregulate the expression of lipolysis factors in PA-treated cells. GPP reduced lipid accumulation and oxidative stress by activating the AMPK/mTOR/AKT signaling pathways, and the most significant effect was detected at 250 μg/mL GPP. Thus, GPP as a dietary phenolic, have the function to regulate lipid metabolism.

Small berry pomaces (SBPs) are poorly utilized as an inexpensive source of bioactive compounds. This study investigated the impact of compounding treatment on nutritional and antioxidant characteristics of combined SBPs, in comparison with single SBP. The results showed that the amounts of protein, minerals, dietary fiber (DF) and anthocyanidins were significantly (p

Steam explosion, as a typical physical-chemical pretreatment technology, destroys the cell wall structure by instantaneous release of high-temperature and high-pressure steam, which promotes the release of plant active ingredients. Appropriate steam explosion pretreatment can significantly improve the extraction rate of free polyphenols, effectively promote the release of polyphenols, and improve the antioxidant capacity. In recent years, steam explosion was applied into the pretreatment of plants and their by-products, and it can significantly improve the extraction of natural active ingredients and enhance functional activity. The influence of steam explosion technology on the content and composition of bound polyphenols and free polyphenols in plants, and the influence on their antioxidant capacity in vitro are summarized in this paper. This would provide a guidance for the use of steam explosion in the food processing industry.

Borago officinalis is a kind of vegetable and traditional medicinal herb in the Mediterranean region, and now it has spread many areas around the world. In this study, we sequenced a complete chloroplast (cp) genome sequence of B. officinalis to investigate its phylogenetic relationship with other species. The whole cp genome of B. officinalis is 149,835 bp in length with 37.82% overall GC content, including a large single-copy (LSC) region of 78,840 bp and a small single-copy (SSC) region of 16,967 bp, which are separated by a pair of inverted repeats (IRs) of 27,014 bp. The cp genome contains 110 genes, including 76 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. The phylogenetic analysis based on cp genome sequences showed that B. officinalis is closely related to Antirhea chinensis, Mitragyna speciosa and Neolamarckia cadamba.

Polyphenols, including extractable polyphenols (EPP) and non-extractable polyphenols (NEPP), are natural and secondary metabolic substances in plants that have beneficial properties to human health. However, NEPP associated with dietary fiber and protein are not taken into account in most literature data. In this paper, NEPP were released from blueberries with acid or alkaline hydrolysis methods, and the related extraction conditions were determined and optimised by response surface methodology (RSM). The results showed that NEPP yield obtained with alkaline hydrolysis was much higher than that obtained with acid treatment. The NEPP yield in alkaline hydrolysis process was significantly affected by the NaOH concentration and liquid/solid ratio, while in the acid hydrolysis process, the NEPP yield was significantly affected by the temperature, time and liquid/solid ratio. The second order polynomial models were developed for predicting NEPP content in blueberries. The optimisation of the extraction process of NEPP in blueberries would provide a good idea and basis for the application of non-extractable fractions.

The total polyphenol (TP), flavonoid, proanthocyanidin (PAC) content, and antioxidant capacity of both onion varieties (red and yellow) were compared. The content of TP, flavonoids, and PAC was determined by Folin-Ciocalteu colorimetric method, AlCl3, and by DMAC colorimetric method, respectively. The results showed that the contents of TP and flavonoids decreased from the outer to the inner layers in both onions, but there was no significant difference in PAC content. The outer layers had the highest antioxidant activity of extracts followed by a continuous decrease towards the inner layers in both varieties. The contents of phenolic acids and flavonoids were quantified by HPLC. Gallic acid, ferulic acid, and quercetin, as the main compounds in polyphenols, were detected in each layer of both onions. The red variety showed better antioxidant activity than yellow onion according to the linoleic acid system and DPPH assay. The higher contents of TP and flavonoids were associated with higher antioxidant activity.

The contents of extractable polyphenols (EPP), non-extractable polyphenols (NEPP), extractable proanthocyanidins (EPAC), non-extractable proanthocyanidins (NEPAC) and extractable anthocyanidins (EAC) in blueberry leaves were investigated. An experiment was conducted to analyse the effect of solvent types (methanol and ethanol), concentration (50 and 70%) and pH (2 and 6) on the extraction of bioactive compounds. Total extractable polyphenols (TEPP), total extractable proanthocyanidins (TEPAC), and total extractable anthocyanidins (TEAC) were analysed in methanol/ethanol/water extracts, NEPP were determined in acidic hydrolysates and NEPAC were quantified by depolymerisation in HCl/butanol. The results showed that ethanol and methanol did not affect the extraction of TEPP, while methanol was better for TEPAC and TEAC. The contents of TEPP and TEAC in 50% solvent were higher than those in 70% solvent. When solvent pH dropped to 2, the contents of EPP and EPAC were increased, while the EAC content was decreased.