Wang Cheng, Li Peiyao, Zhang Beibei, Yu Xiang, Li Xingang, Han Gang, Ren Yamei, Zhang Jingfang
College of Forestry, Northwest A&F University, Xianyang 712100, China.
College of Chemistry and Chemical Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
Foods. 2022 Aug 23;11(17):2546. doi: 10.3390/foods11172546.
As an important medicine homologous food, Chinese jujube is rich in nutrition and medicinal value. To enhance the bioactive compounds level of Chinese jujube products, three kinds of fungi strains (, and ) were firstly selected to evaluate their effects on total soluble phenolic compounds (TSPC) and total soluble flavonoids compounds (TSFC) contents during liquid state fermentation of Chinese jujube. As the best strain, the highest contents of TSPC and TSFC could increase by 102.1% (26.02 mg GAE/g DW) and 722.8% (18.76 mg RE/g DW) under fermentation when compared to the unfermented sample, respectively. Qualitative and quantitative analysis of individual polyphenol compounds indicated that proto-catechuic acid, -hydroxybenzoic acid and chlorogenic acid showed the highest level in the fer-mented Chinese jujube at the 7th day, which was enhanced by 16.72-, 14.05- and 6.03-fold when compared to the control, respectively. Combining with RNA sequencing, function annotation of CAZymes database and polyphenol profiling, three potential transformation pathways of poly-phenol compounds were proposed in the fermented Chinese jujube by , such as the conversion of insoluble bound phenolic acids, rutin and anthocyanin degradation. These findings would be beneficial for better understanding of the biotransformation mechanism of polyphenol compounds in fungi fermentation.
作为一种重要的药食同源食品，红枣营养丰富且具有药用价值。为提高红枣产品中生物活性化合物的含量，首先筛选了三种真菌菌株（、和），以评估它们在红枣液态发酵过程中对总可溶性酚类化合物（TSPC）和总可溶性黄酮类化合物（TSFC）含量的影响。作为最佳菌株，在发酵条件下，与未发酵样品相比，TSPC和TSFC的最高含量分别可提高102.1%（26.02毫克没食子酸当量/克干重）和722.8%（18.76毫克芦丁当量/克干重）。对单个多酚化合物的定性和定量分析表明，原儿茶酸、对羟基苯甲酸和绿原酸在发酵第7天的红枣中含量最高，与对照相比分别提高了16.72倍、14.05倍和6.03倍。结合RNA测序、CAZymes数据库功能注释和多酚谱分析，提出了在发酵红枣中多酚化合物的三种潜在转化途径，如不溶性结合酚酸的转化、芦丁和花青素的降解。这些发现将有助于更好地理解真菌发酵中多酚化合物的生物转化机制。
