Miyazawa M, Okuno Y, Oshiro K, Kasahara H, Shimamura H, Nakamura S, Kameoka H
Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University Kowakae, Osaka, Japan.
Biosci Biotechnol Biochem. 1998 Jul;62(7):1425-7.
The methanol extract from Machilus thunbergii showed a suppressive effect on umu gene expression of the SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), which requires liver metabolizing enzymes. The methanol extract from M. thunbergii was successively re-extracted with chloroform, butanol and water. A suppressive compound in the chloroform extract fraction was isolated by SiO2 column chromatography and identified as meso-dihydroguaiaretic acid by GC-MS, and 1H- and 13C-NMR spectroscopy. Meso-dihydroguaiaretic acid inhibited of the SOS-inducing activity of Trp-P-1 in the umu test. Gene expression was suppressed by 62% at less than 0.18 mumol/ml, the ID50 value being 0.08 mumol/ml. Compound 1 was also assayed with aflatoxin B1 (AfB1) and showed a suppressive effect.
厚壳桂甲醇提取物对鼠伤寒沙门氏菌TA1535/pSK1002中SOS应答的umu基因表达具有抑制作用，该应答针对诱变剂3-氨基-1,4-二甲基-5H-吡啶并[4,3-b]吲哚（Trp-P-1），此诱变剂需要肝脏代谢酶的参与。厚壳桂甲醇提取物依次用氯仿、丁醇和水进行再提取。氯仿提取物部分中的一种抑制性化合物通过硅胶柱色谱法分离，并经气相色谱-质谱联用（GC-MS）以及氢核磁共振（1H-NMR）和碳核磁共振（13C-NMR）光谱鉴定为内消旋二氢愈创木酸。内消旋二氢愈创木酸在umu试验中抑制了Trp-P-1的SOS诱导活性。在浓度低于0.18 μmol/ml时，基因表达被抑制了62%，半数抑制浓度（ID50）值为0.08 μmol/ml。化合物1还用黄曲霉毒素B1（AfB1）进行了检测，结果显示具有抑制作用。
