Sato T, Ose Y, Nagase H, Hayase K
Mutat Res. 1987 Feb;176(2):199-204. doi: 10.1016/0027-5107(87)90050-9.
The mechanism of an apparent desmutagenic effect of humic acid was investigated. Firstly, components of humic acid (resorcinol, vanillin, vanillic acid, ferulic acid, protochatechuic acid and benzoic acid) were tested and were not found to show a desmutagenic effect. By contrast, lignin did show a desmutagenic effect. The desmutagenic effect of humic acid was decreased by ozone treatment, and the degree of decrease corresponded with a decrease in KMnO4 consumption. Benzo[a]pyrene and humic acid were incubated at 37 degrees C for 1 h and extracted by ethyl acetate and the extract was investigated by gas chromatography (GC). The peak of the decomposition product did not appear, but the amount of benzo[a]pyrene was decreased. This suggests that the desmutagenic effect of humic acid was caused by adsorption of benzo[a]pyrene by humic acid rather than by decomposition of benzo[a]pyrene. Humic acid had the largest adsorption activity at its critical micelle concentration (CMC), while adsorbed benzo[a]pyrene could be released by ultrasonication. Fulvic acid and water-soluble humic substance showed a slight inhibitory effect on the mutagenicity of benzo[a]pyrene.
研究了腐殖酸明显的抗诱变作用机制。首先，对腐殖酸的成分（间苯二酚、香草醛、香草酸、阿魏酸、原儿茶酸和苯甲酸）进行了测试，未发现其具有抗诱变作用。相比之下，木质素确实表现出抗诱变作用。腐殖酸的抗诱变作用经臭氧处理后降低，降低程度与高锰酸钾消耗量的减少相对应。将苯并[a]芘与腐殖酸在37℃下孵育1小时，用乙酸乙酯萃取，萃取物用气相色谱法（GC）进行研究。分解产物的峰未出现，但苯并[a]芘的量减少。这表明腐殖酸的抗诱变作用是由腐殖酸对苯并[a]芘的吸附而非苯并[a]芘的分解引起的。腐殖酸在其临界胶束浓度（CMC）时具有最大的吸附活性，而吸附的苯并[a]芘可通过超声处理释放出来。富里酸和水溶性腐殖物质对苯并[a]芘的致突变性表现出轻微的抑制作用。
