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Summary: Asp‐Leu‐Glu‐Glu (DLEE) is one of the antioxidant peptides purified from Chinese dry‐cured Xuanwei ham in our previous study. In the current work, the stability in a simulated digestion system, the transportation pathway and the antioxidant ability of DLEE were further investigated in a Caco‐2 cell monolayer. In the simulated gastrointestinal digestion system, no oligopeptides were generated. In the transport trial, the inhibitors cytochalasin D increased the transport of DLEE across the Caco‐2 cell monolayer, with Papp values of 3.22 × 10−6 cm s−1. A decreased expression occludin was observed with the DLEE incubation in the cell monolayer, and the antioxidant activity showed to be increased gradually in basolateral side. This study indicates that the absorption of DLEE could mainly occur via paracellular transport and provides information about its antioxidant activity after being absorbed across a cell monolayer. [ABSTRACT FROM AUTHOR]

Flaxseed (Linum usitatissimum L.) is well known for its health benefits and chemical composition. This study aimed to evaluate the dynamic changes caused by germination in vitamin C, phenolic compounds and antioxidant activities of flaxseed. It was observed that eight-day germination of flaxseed sprouts caused increases in phytochemical contents, that is 22.1-fold increase in vitamin C, 2.67-fold increase in phenolics and 5.48-fold increase in flavonoid contents as compare to initial concentration in flaxseeds on dry weight basis. The stimulation was also noted in the three identified phenolic acid ingredients including caffeic acid, p-coumaric acid and ferulic acid. Similarly, the total PSC and ORAC values of flax sprouts at day 8 increased by 3- to 4-folds compared to nongerminated flaxseeds. It is revealed that comparatively, 8-day germination of flax sprouts leads to a significant increase in vitamin C, phenolic constituents and total antioxidant activities than those of flaxseeds. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to study the dynamic changes of ascorbic acid, tocopherols and their antioxidant activity of soya bean sprouts during germination. Results showed that the expression levels of genes related to biosynthesis of ascorbic acid and tocopherols dramatically increased during germination. The expression levels of most genes were up to the peak at day 3 and kept constantly until the end of germination. The contents of ascorbic acid, α-tocopherol, γ-tocopherol, δ-tocopherol and total tocopherols increased during soya bean sprouts germination and reached peak levels on day 5, of 74.42 ± 1.64 mg/100 g DW, 7.64 ± 0.13 mg/100 g DW, 15.84 ± 1.85 mg/100 g DW, 12.37 ± 1.06 mg/100 g DW, 35.85 ± 2.81 mg/100 g DW, respectively. The antioxidant activity of soya bean sprouts increased during germination and reached peak level on day 5 to 311.01 ± 49.01 μmol ASA equiv./100 g DW. Therefore, germination significantly increased the biosynthesis of ascorbic acid, tocopherols and antioxidant activity of soya bean sprouts. [ABSTRACT FROM AUTHOR]

Phenolics are suggested to be the major bioactive compounds responsible for the health benefits of tea. Seven types of tea were extracted using boiling water. The extraction kinetics was investigated. To more fully characterise the antioxidant profiles and possible associated health benefits of these tea types, the total water-soluble solid content, phenolics, flavonoids, and antioxidant and antiproliferative activities were quantified. Green tea leaves ( GTL) were found to have the highest phenolic content (128.7 ± 1.7 mg g−1 , P < 0.05), followed by teas of decaffeinated green tea bag (d GTB), green tea bag ( GTB), black tea bag ( BTB), decaffeinated BTB, black tea leaves and oolong tea leaves ( OTL). Among the three leaf teas, GT displayed the greatest antioxidant activity (4850.2 ± 60.7 μmol g−1, P < 0.05), followed by black tea ( BT) and oolong tea ( OT). As for the four bag teas, decaffeinated GT possessed the strongest antioxidant activity (4431.1 ± 335.0 μmol g−1, P < 0.05), followed by GT, BT and decaffeinated BT. The results display that phenolic/flavonoid content well correlated with antioxidant activity. Proliferation of three human cancer cells was significantly inhibited in a dose-dependent manner after exposure to some tea extracts. This may influence consumers in selecting the type of tea and tea brewing times, exhibiting greater health benefits. [ABSTRACT FROM AUTHOR]