Phenolic, fatty acid, and phytosterol contents in sweet potato (SP) fermented by Lactobacillus acidophilus were evaluated and compared with those of raw and boiled SPs. The differences in the profiles and levels of phenolics between the raw and boiled SPs were not as significant as the differences between those and the fermented SP. The levels of caffeic acid and 3,5-dicaffeoylquinic acid in fermented SP were more than 4 times higher than those in raw and boiled SPs. Two phenolics, p-coumaric acid and ferulic acid, which were not detected in either raw or boiled SP, were found in fermented SP. The level of each fatty acid or phytosterol increased in fermented SP and decreased in boiled SP. Among the hydrophilic and lipophilic extracts obtained from raw and fermented SPs, the hydrophilic extract of fermented SP exhibited the highest capability of inhibiting cancer-cell PC-12 proliferation. However, each of the extracts had very low cytotoxicities to normal-monkey-kidney-cell growth. The results indicated that SP fermented by L. acidophilus significantly increased free antioxidant-rich phenolics and inhibited cancer-cell-proliferation activity without cytotoxicity to normal cells.

中文翻译：

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嗜酸乳杆菌发酵后甘薯中酚，脂肪酸和植物甾醇含量的增加及抗癌活性

评估了嗜酸乳杆菌发酵的甘薯（SP）中酚，脂肪酸和植物甾醇的含量，并将其与生和煮沸的SP的含量进行了比较。生的和煮沸的SP之间的酚类特征和含量差异不如SP和发酵的SP之间的差异显着。发酵的SP中的咖啡酸和3,5-二咖啡酰奎尼酸的含量比生的和煮沸的SP中的高4倍以上。两种酚，p在发酵的SP中未检出-香豆酸和阿魏酸，无论是在原始SP还是在沸腾的SP中均未检测到。发酵的SP中每种脂肪酸或植物甾醇的含量增加，而煮沸的SP中每种脂肪酸或植物甾醇的含量降低。在从原始和发酵的SP获得的亲水性和亲脂性提取物中，发酵的SP的亲水性提取物表现出最高的抑制癌细胞PC-12增殖的能力。但是，每种提取物对正常猴肾细胞的生长都具有极低的细胞毒性。结果表明，被嗜酸乳杆菌发酵的SP显着增加了富含游离抗氧化剂的酚类，并抑制了癌细胞的增殖活性，而对正常细胞没有细胞毒性。