Ability of intestinal lactic bacteria to bind or/and metabolise phenol and p-cresol
Ability of intestinal lactic bacteria to bind or/and metabolise phenol and p-cresol
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DOI：
10.1007/bf03175068
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发表时间：
2007-01-01
影响因子：
3
通讯作者：
Libudzisz, Zdzislawa
中科院分区：
文献类型：
--
作者：
Nowak, Adriana;Libudzisz, Zdzislawa
肠道微生物区系可以通过产生在致癌作用中发挥作用的物质而促成结肠癌。蛋白质在结肠中发酵产生的代谢产物，如氨、H2S、吲哚、苯酚、粪臭素等都是有毒物质。存在于结肠中的乳酸菌可能发挥抗癌作用，但其机制知之甚少。在本研究中，测定了肠乳酸杆菌在体外结合或代谢苯酚和对甲酚的能力。将乳杆菌菌株在MRS和具有降低浓度的碳源的改良MRS肉汤中培养。培养基中的苯酚和对甲酚含量为2至10 μ g/ml。在MRS培养基中，乳酸杆菌能降低苯酚和对甲酚的浓度，其浓度分别为0.2-5.8 μ g/ml和0.2-1.4 μ g/ml。在改良的MRS肉汤中培养后，苯酚和对甲酚的减少量分别为0.5-2.0 μ g/ml和0.5-2.4 μ g/ml。细菌细胞的结合能力相当低。在培养非生长细菌后，苯酚浓度降低0.1-0.5 μ g/ml，对甲酚降低0.1-2.8 μ g/ml。但是不能排除生长中的乳酸杆菌代谢这些化合物的能力。在乳酸杆菌与10 μ g/ml苯酚相互作用后，通过碱性彗星试验评价，它们显示出较低的遗传毒性。这种现象并不总是依赖于苯酚浓度的降低，但取决于培养基，细菌的菌株和苯酚的范围从32%到48%。测试的乳酸杆菌菌株没有降低对甲酚的遗传毒性。
Intestinal microflora can contribute to colon cancer by the production of substances playing a role in carcinogenesis. Metabolites of protein fermentation in the colon, such as ammonia, H2S, indole, phenol, skatole are toxic. Lactic bacteria existing in the colon may exert an anti-carcinogenic action, but the mechanism is poorly understood. In the present study the ability of intestinal lactobacilli to bind or metabolise phenol and p-cresol in vitro was determined. Lactobacillus strains were cultivated in MRS and in a modified MRS broth with reduced concentrations of carbon source. Phenol and p-cresol content in the media were from 2 to 10 mu g/ml. In MRS medium lactobacilli could decrease the concentration of phenol and p-cresol and it was 0.2-5.8 mu g/ml for phenol and 0.2-1.4 mu g/ml for p-cresol. After cultivation in a modified MRS broth, the decrease was 0.5-2.0 mu g/ml for phenol and 0.5-2.4 mu g/ml for p-cresol. The binding capacity of bacterial cells was rather low. After incubation of non-growing bacteria the decrease of phenol concentration was 0.1-0.5 mu g/ml and p-cresol 0.1-2.8 mu g/ml. But the ability of growing lactobacilli to metabolise the compounds cannot be excluded. After interaction of lactobacilli with 10 mu g/ml of phenol they displayed a lower genotoxicity, as evaluated by the alkaline comet assay. The phenomenon not always depended on the decrease of phenol concentration, but on the medium, the strain of bacteria and for phenol it ranged from 32 to 48%. Lactobacillus strains tested did not lower the genotoxicity of p-cresol.