Nowak Adriana, Śliżewska Katarzyna, Otlewska Anna
Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland.
Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland.
Regul Toxicol Pharmacol. 2015 Dec;73(3):938-46. doi: 10.1016/j.yrtph.2015.09.021. Epub 2015 Sep 25.
Dietary components such as lactic acid bacteria (LAB) and prebiotics can modulate the intestinal microbiota and are thought to be involved in the reduction of colorectal cancer risk. The presented study measured, using the comet assay, the antigenotoxic activity of both probiotic and non-probiotic LAB, as well as some prebiotics and the end-products of their fermentation, against fecal water (FW). The production of short chain fatty acids by the bacteria was quantified using HPLC. Seven out of the ten tested viable strains significantly decreased DNA damage induced by FW. The most effective of them were Lactobacillus mucosae 0988 and Bifidobacterium animalis ssp. lactis Bb-12, leading to a 76% and 80% decrease in genotoxicity, respectively. The end-products of fermentation of seven prebiotics by Lactobacillus casei DN 114-001 exhibited the strongest antigenotoxic activity against FW, with fermented inulin reducing genotoxicity by 75%. Among the tested bacteria, this strain produced the highest amounts of butyrate in the process of prebiotic fermentation, and especially from resistant dextrin (4.09 μM/mL). Fermented resistant dextrin improved DNA repair by 78% in cells pre-treated with 6.8 μM methylnitronitrosoguanidine (MNNG). Fermented inulin induced stronger DNA repair in cells pre-treated with mutagens (FW, 25 μM hydrogen peroxide, or MNNG) than non-fermented inulin, and the efficiency of DNA repair after 120 min of incubation decreased by 71%, 50% and 70%, respectively. The different degrees of genotoxicity inhibition observed for the various combinations of bacteria and prebiotics suggest that this effect may be attributable to carbohydrate type, SCFA yield, and the ratio of the end-products of prebiotic fermentation.
乳酸菌（LAB）和益生元等膳食成分可调节肠道微生物群，被认为与降低结直肠癌风险有关。本研究使用彗星试验测量了益生菌和非益生菌LAB、一些益生元及其发酵终产物对粪便水（FW）的抗遗传毒性活性。使用高效液相色谱法对细菌产生的短链脂肪酸进行定量。在所测试的10种活菌株中，有7种显著降低了FW诱导的DNA损伤。其中最有效的是黏液乳杆菌0988和动物双歧杆菌乳亚种Bb-12，分别使遗传毒性降低了76%和80%。干酪乳杆菌DN 114-001对7种益生元的发酵终产物对FW表现出最强的抗遗传毒性活性，发酵菊粉使遗传毒性降低了75%。在所测试的细菌中，该菌株在益生元发酵过程中产生的丁酸盐量最高，尤其是来自抗性糊精（4.09μM/mL）。发酵抗性糊精使经6.8μM甲基亚硝基胍（MNNG）预处理的细胞中的DNA修复提高了78%。与未发酵菊粉相比，发酵菊粉在用诱变剂（FW、25μM过氧化氢或MNNG）预处理的细胞中诱导更强的DNA修复，孵育120分钟后DNA修复效率分别降低了71%、50%和70%。对细菌和益生元的各种组合观察到的不同程度的遗传毒性抑制表明，这种效应可能归因于碳水化合物类型、短链脂肪酸产量以及益生元发酵终产物的比例。
