Fruits and vegetables are considered a good source of polyphenols and antioxidant capacities which are beneficial in protecting the human body against damage induced by reactive species. The objective of this work is to conduct an assessment of the polyphenol content and antioxidant activities of different fruit (kiwi, pear, green apple, raspberry, blackberry, strawberry and blueberry) and vegetable (pumpkin, green and red pepper) extracts using both chemical extraction and a modified in vitro digestive enzymatic extraction in order to compare results. Polyphenol content and antioxidant capacity of different fruits, vegetables and fruit juices were determined by Folin-Ciocalteu and FRAP methods, respectively. It was observed that polyphenol content expressed as gallic acid equivalents of extracts obtained with the two extraction methods was significantly (p<0.05) different (on average 310.3 and 231.8 mg per 100 g of fresh sample in enzymatic and methanolic extracts, respectively). Antioxidant capacity was also significantly (p<0.05) different in the extracts obtained by the two methods, with higher values in enzymatic extracts (1.91 mmol of Fe²⁺ per 100 g of fresh sample). Analyses of apple samples with and without skin also revealed important differences related to methodology and composition. Additionally, the original enzymatic extraction method was improved to avoid interferences caused by the presence of protein residues in the extract.

中文翻译：

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使用改良酶法提取评估水果和蔬菜的多酚含量和抗氧化能力。

水果和蔬菜被认为是多酚和抗氧化能力的良好来源，有利于保护人体免受活性物质引起的损害。这项工作的目的是使用化学方法评估不同水果（猕猴桃、梨、青苹果、覆盆子、黑莓、草莓和蓝莓）和蔬菜（南瓜、青椒和红辣椒）提取物的多酚含量和抗氧化活性。提取和改良的体外消化酶提取，以比较结果。分别采用Folin-Ciocalteu法和FRAP法测定不同水果、蔬菜和果汁的多酚含量和抗氧化能力。据观察，两种提取方法获得的提取物中以没食子酸当量表示的多酚含量存在显着差异（p<0.05）（酶提取物和甲醇提取物中平均每 100 g 新鲜样品分别含有 310.3 mg 和 231.8 mg）。两种方法获得的提取物的抗氧化能力也存在显着差异（p<0.05），酶提取物的抗氧化能力较高（每 100 g 新鲜样品含有1.91 mmol Fe ^{2+ ）。}对带皮和不带皮苹果样品的分析还揭示了与方法和成分相关的重要差异。此外，对原有的酶法提取方法进行了改进，以避免提取物中存在蛋白质残留物造成的干扰。