Abstract：
This study investigated the transformation of polyphenols, including free and bound polyphenols during the fermentation of wolfberry juice by Lactobacillus plantarum NCU137. Results indicated that fermentation significantly increased the free polyphenols content and released bound polyphenols, enhancing the antioxidant activity. Analysis showed that there were 19 free polyphenols, mainly scopoletin, pyrogallol, and dihydroferulic acid, and 16 bound polyphenols, especially p-coumaric acid, feruloyl hexoside, and caffeic acid. A significant correlation was observed between the generation and degradation of polyphenols, and specific bound polyphenols peaked during the 24-48 h fermentation. Furthermore, reduced surface roughness and galacturonic acid content in wolfberry residue, along with increased pectinase activity, suggested substantial pectin degradation in the cell wall, which may be associated with the release of polyphenols, due to pectin serving as carriers for bound polyphenols. The fermentation also increased polyphenol oxidase and peroxidase activity, contributing to polyphenol breakdown. These findings provide insights for improving wolfberry juice production.
摘要：
本研究调查了多酚的转化，包括植物乳杆菌NCU137发酵枸杞汁过程中的游离和结合多酚。结果表明，发酵显著增加了游离多酚含量和释放结合多酚，增强抗氧化活性。分析表明，有19种游离多酚，主要是Scopotletin,邻苯三酚,和二氢阿魏酸,和16种结合的多酚，尤其是对香豆酸,阿魏酸己苷,和咖啡酸。在多酚的产生和降解之间观察到显着的相关性，和特定结合的多酚在24-48小时发酵期间达到峰值。此外，降低了枸杞渣中的表面粗糙度和半乳糖醛酸含量，随着果胶酶活性的增加，表明细胞壁中的果胶大量降解，这可能与多酚的释放有关，由于果胶作为结合多酚的载体。发酵还增加了多酚氧化酶和过氧化物酶的活性，有助于多酚分解。这些发现为改善枸杞汁生产提供了见解。
