Institute of Food Science and Nutrition, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, 29122 Piacenza, Italy.
Department for Sustainable Food Process, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, 29122 Piacenza, Italy.
Food Chem. 2018 Apr 15;245:633-640. doi: 10.1016/j.foodchem.2017.10.146. Epub 2017 Nov 5.
A bioaccessibility study of polyphenols after in vitro simulated large intestine fermentation was carried out on edible nuts. Raw nuts were also analysed for total phenolic content and antioxidant potential, considering both bound and free phenolics. The highest phenolic content was found in walnuts, followed by pistachios extracts (596.9 and 410.1 mg gallic acid equivalents 100 g, respectively). Consistently, the total antioxidant capacity was highest in walnuts (3689.7 μM trolox equivalents 100 g) followed by peanuts and pistachios (3169.6 and 2990.1 μM trolox equivalents 100 g, respectively). Data showed high correlations between total phenolics and both antioxidant activities. The metabolomics-based phenolic profile depicted during in vitro fermentation showed a degradation of higher-molecular-weight phenolics over 48 hours of faecal fermentation, with a concurrent increase in low-molecular-weight compounds (hydroxybenzoic and hydroxycinnamic acids, alkylphenols, and tyrosols). Our findings indicate that nuts deliver polyphenols into the colon, with bioaccessibility values not negligible for alkylphenols, tyrosols and phenolic acids.
对食用坚果进行了体外模拟大肠发酵后多酚的生物利用度研究。还分析了生坚果的总酚含量和抗氧化潜力，同时考虑了结合态和游离态酚。核桃的酚类含量最高，其次是开心果提取物（分别为 596.9 和 410.1mg 没食子酸当量/100g）。同样，核桃的总抗氧化能力最高（3689.7μM Trolox 当量/100g），其次是花生和开心果（分别为 3169.6 和 2990.1μM Trolox 当量/100g）。数据显示总酚与两种抗氧化活性之间存在高度相关性。基于代谢组学的酚类图谱在体外发酵过程中显示，在 48 小时的粪便发酵过程中，高分子量酚类物质降解，同时低分子量化合物（羟基苯甲酸和羟基肉桂酸、烷基酚和酪醇）增加。我们的研究结果表明，坚果将多酚输送到结肠，烷基酚、酪醇和酚酸的生物利用度值不容忽视。
