摘要
以6株乳酸菌纯种发酵葛根酵素,发酵结束后测定葛根酵素的活菌数、pH值、总酸、还原糖含量、总酚含量,采用两种体外抗氧化活性测定方法(ABTS和FRAP)评价发酵酵素的抗氧化能力,通过高效液相色谱法测定葛根酵素中葛根素等主要异黄酮的含量和乳酸等主要有机酸的含量。通过主成分分析(PCA)方法来拟合整体的数据并建立综合评价模型,优选出适合发酵葛根酵素的菌种。结果显示,发酵的葛根酵素活菌数均达到8.0 lg(CFU/mL),pH值降至3.60以下;还原糖含量减少9.1%~17.9%,总酸含量最高达8.47 g/1000 g,有机酸的组成和含量变化显著;葛根酵素的总酚含量变化不显著,体外抗氧化活性得到有效保持。此外,发酵后大豆苷元和染料木素最多增加了40.7%和39.9%。PCA结果显示:前3个主成分的累计方差贡献率为85.9%,可综合反映发酵酵素的品质。德氏乳杆菌保加利亚亚种GIM1.155(1.825分)、嗜酸乳杆菌GIM1.321(1.174分)和植物乳杆菌R4(0.621分)的综合评价总得分排名靠前,表明它们在生长代谢和功能作用方面表现更优。与纯种发酵相比,采用这3株菌作为复合发酵剂制备的葛根酵素的品质有所改善。研究结果可为葛根酵素的复合发酵提供理论参考。
Six strains of lactic acid bacteria were used for Pueraria lobata enzymes pure fermentation.After fermentation,the number of viable bacteria count,pH values,total acidity,reducing sugar content,and total phenols content of Pueraria lobata enzymes were determined.Two in vitro antioxidant activity determination methods(ABTS and FRAP)were used to evaluate the antioxidant capacity of fermented Pueraria lobata enzymes.The contents of major isoflavones such as puerarin and major organic acids such as lactic acid in Pueraria Lobata enzymes were determined by high performance liquid chromatography.A principal component analysis(PCA)method was used to fit the overall data and establish a comprehensive evaluation model to select the strains suitable for fermentation of Pueraria Lobata enzymes.The results showed that the fermented Pueraria lobata enzymes all had a viable count of 8.0 lg(CFU/mL)and the pH value decreased to below 3.60.The reducing sugar content decreased from 9.1%to 17.9%after fermentation,and the total acid content reached up to 8.47 g/1000 g.The composition and content of organic acids changed significantly.The total phenols content of Pueraria lobata enzymes did not change significantly after fermentation,and the in vitro antioxidant activity was effectively maintained.In addition,the contents of daidzein and genistein increased up to 40.7%and 39.9%after fermentation.The PCA results showed that cumulative variance contribution rate of the first three principal components was 85.9%,which could reflect the quality of the fermented enzyme comprehensively.Lactobacillus delbrueckii subsp.bulgaricus GIM1.155(1.825 points),Lactobacillus acidophilus GIM1.321(1.174 points)and Lactiplantibacillus plantarum R4(0.621 points)ranked high in the overall evaluation score,indicating that they performed better in terms of growth,metabolism and functions.Compared with pure fermentation,the quality of Pueraria lobata enzymes prepared using these three strains as a mixed starter culture was improved.The results of the study c
作者
杨玉
李红艳
邓泽元
傅小华
赖长龙
范亚苇
Yang Yu;Li Hongyan;Deng Zeyuan;Fu Xiaohua;Lai Changlong;Fan Yawei(Nanchang University,State Key Laboratory of Food Science and Technology,Nanchang 330047;Jiangxi Baihe Pharmaceutical Co.,Ltd,Zhangshu 331200,Jiangxi)
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2023年第3期196-205,共10页
Journal of Chinese Institute Of Food Science and Technology
关键词
葛根酵素
乳酸菌
主成分分析:复合发酵
Pueraria lobata enzymes
Lactobacillus
principal component analysis
mixed culture fermentation
