Doğan Cömert Ezgi, Gökmen Vural, Capuano Edoardo
Food Quality and Safety (FoQuS) Research Group, Department of Food Engineering, Hacettepe University, Ankara, Turkey.
Food Quality and Design, Wageningen University and Research, Wageningen, The Netherlands.
Food Funct. 2025 Aug 11;16(16):6637-6649. doi: 10.1039/d5fo01281c.
Bound antioxidants play a significant role in human health due to their slow and continuous release throughout the colon. Oat bran (OB) is a key source of bound antioxidants; however, its antioxidant capacity is limited. This capacity could be enhanced through treatment with green tea infusion (GTI) under optimum conditions, resulting in GTI treated OB. This study investigated the release of antioxidants from GTI treated OB during both digestion and colonic fermentation using batch and SHIME model systems. Antioxidant capacity was determined in both soluble and insoluble fractions using the QUENCHER approach. The released antioxidant capacity during batch fermentation was associated with catechin metabolites. The effects on gut microbiota metabolites, specifically short chain fatty acids (SCFA), were examined. Additionally, the interaction between OB and green tea extract (GTE), referred to as OB + GTE, during co-digestion and fermentation was tested. Compared to GTE alone and OB + GTE, GTI treated OB showed superior antioxidant activity (2-6-fold higher) in both insoluble and soluble fractions during short- and long-term exposure. The antioxidant release during fermentation of GTI treated OB was strongly correlated with the concentration of pyrogallol ( = 0.693) and 3,4-dihydroxyphenylacetic acid ( = 0.625). Half of its antioxidant capacity remained in the insoluble fraction. Both GTI treated OB and OB + GTE stimulated SCFA production, with concentrations of 25.25 ± 2.53 mM and 30.62 ± 5.03 mM in the distal colon, respectively. These findings suggest that the enhanced bound antioxidant capacity of OB has beneficial health effects on colon health by increasing antioxidant capacity and stimulating SCFA production.
结合抗氧化剂在人体健康中发挥着重要作用，因为它们在整个结肠中缓慢而持续地释放。燕麦麸（OB）是结合抗氧化剂的关键来源；然而，其抗氧化能力有限。在最佳条件下用绿茶浸提液（GTI）处理可以提高这种能力，从而得到GTI处理的OB。本研究使用分批和SHIME模型系统，研究了GTI处理的OB在消化和结肠发酵过程中抗氧化剂的释放情况。使用QUENCHER方法测定了可溶和不溶部分的抗氧化能力。分批发酵过程中释放的抗氧化能力与儿茶素代谢产物有关。研究了对肠道微生物群代谢产物，特别是短链脂肪酸（SCFA）的影响。此外，还测试了OB与绿茶提取物（GTE）在共消化和发酵过程中的相互作用，即OB + GTE。与单独的GTE和OB + GTE相比，GTI处理的OB在短期和长期暴露期间，在不溶和可溶部分均表现出更高的抗氧化活性（高2 - 6倍）。GTI处理的OB在发酵过程中的抗氧化剂释放与连苯三酚（r = 0.693）和3,4 - 二羟基苯乙酸（r = 0.625）的浓度密切相关。其抗氧化能力的一半保留在不溶部分。GTI处理的OB和OB + GTE均刺激了SCFA的产生，在远端结肠中的浓度分别为25.25±2.53 mM和30.62±5.03 mM。这些发现表明，OB增强的结合抗氧化能力通过提高抗氧化能力和刺激SCFA产生，对结肠健康具有有益的健康影响。
