益生菌发酵胡萝卜汁活性成分与抗氧化活性研究

研究了鼠李糖乳杆菌（Lactobacillus rhamnus）发酵胡萝卜汁前后游离酚、结合酚、有机酸、游离氨基酸及抗氧化活性的变化。结果表明，鼠李糖乳杆菌发酵后胡萝卜汁中的游离态酚类物质含量明显增加（P＜0.05），而结合态酚类物质的含量明显下降（P＜0.05），其中槲皮素相较于发酵前提高了243.91%；发酵后乳酸含量最高，比发酵前提高了5.376 mg/mL；发酵后苏氨酸（0.13 mg/g）、丝氨酸（0.25 mg/g）、甘氨酸（0.34 mg/g）、蛋氨酸（0.05 mg/g）和赖氨酸（0.12 mg/g）含量均明显升高（P＜0.05）。抗氧化活性实验结果表示，发酵后的胡萝卜汁对DPPH和羟基自由基的清除率及总还原力分别为70.6%和26.45%及0.58±0.01，比发酵前分别提高了30.42%和21.45%及28.89%。

Active constituents and antioxidant activity of fermented carrot juice by probiotics

The changes of free polyphenols, combined polyphenols, organic acid, free amino acid and antioxidant activity in fermented carrot juice by Lactobacillus rhamnus were researched. The results showed that the content of free phenols in the fermented carrot juice increased significantly (P＜0.05), the content of bound phenols decreased significantly (P＜0.05), and the quercetin content increased 243.91% compared with that before fermentation. After the fermentation, the lactic acid content was the highest, which was 5.376 mg/ml higher than that of before fermentation, and 5 kinds of amino acids contents increased significantly after fermentation (P＜0.05), including threonine (0.13 mg/g), serine (0.25 mg/g), glycine (0.34 mg/g), methionine (0.05 mg/g) and lysine (0.12 mg/g). After fermentation, the scavenging rates of the carrot juice on DPPH and hydroxyl free radical and total reducing power were 70.6% and 26.45%, respectively, which were 30.42%, 21.45% and 28.89% higher than that of before fermentation.