Lin J K, Hurng D C
Institute of Biochemistry, College of Medicine, National Taiwan University, Taipei, Republic of China.
Food Chem Toxicol. 1989 Sep;27(9):613-8. doi: 10.1016/0278-6915(89)90021-5.
The levels of trimethylamine N-oxide (TMAO) in the New Zealand (Nototodarus sloani) species of squid extracts were extremely high (above 9200 ppm). When the extracts were incubated for 2 days at 25 degrees C, approximately 60% TMAO was converted to trimethylamine (TMA) and dimethylamine (DMA). This conversion was very low or negligible at 4 degrees C, but was potentiated by the presence of ferrous sulphate (0.014 M) and ascorbate (0.014 M). Citrobacter freundii and Aeromonas hydrophilia were isolated from the extracts. Cultures of these two micro-organisms and of Escherichia coli were active in catalysing the conversion of TMAO to TMA and DMA either in extract or in aqueous solution. Chloramphenicol (0.416 mg/ml) completely inhibited the growth of these micro-organisms and also effectively blocked the conversion of endogenous TMAO to TMA in the extracts. The present findings suggest that gastro-intestinal flora and dietary ferrous salts and ascorbate may play important roles in the conversion of TMAO to TMA and DMA in man following the ingestion of squid and other TMAO-containing seafoods.
新西兰斯氏柔鱼提取物中的氧化三甲胺（TMAO）含量极高（超过9200 ppm）。当提取物在25℃下孵育2天时，约60%的TMAO转化为三甲胺（TMA）和二甲胺（DMA）。在4℃时这种转化非常低或可忽略不计，但硫酸亚铁（0.014 M）和抗坏血酸盐（0.014 M）的存在会增强这种转化。从提取物中分离出了弗氏柠檬酸杆菌和嗜水气单胞菌。这两种微生物以及大肠杆菌的培养物在提取物或水溶液中都能有效催化TMAO转化为TMA和DMA。氯霉素（0.416 mg/ml）完全抑制了这些微生物的生长，也有效阻断了提取物中内源性TMAO向TMA的转化。目前的研究结果表明，在摄入鱿鱼和其他含TMAO的海鲜后，胃肠道菌群以及膳食中的亚铁盐和抗坏血酸盐可能在人体将TMAO转化为TMA和DMA的过程中发挥重要作用。
