AbstractA new microbial isolate,Flavobacterium sp. strain DS5, converts linoleic acid into 10‐hydroxy‐12(Z)‐octadecenoic acid (10‐HOA) with 55% yield. The product was characterized by gas chromatography (GC), GC/mass spectrometry, nuclear magnetic resonance and Fourier transform infrared spectroscopy. The specific optical rotation of 10‐HOA is [α]D24=−5.58 (methanol). The optimum time, pH and temperature for the production of 10‐HOA were 36h, 7.5 and 20–35°C, respectively. The enzyme(s) that converts linoleic acid to 10‐HOA is soluble and located intracellulary in strain DS5. Two minor products, 10‐methoxy‐12‐octade‐cenoic acid and 10‐keto‐12‐octadecenoic acid, were also identified. 10‐HOA was further metabolized by strain DS5. Among the unsaturated fatty acids studied, the order of reactivity for the DS5 enzyme(s) is oleic>palmitoleic> linoleic>linolenic>γ‐linolenic>myristoleic acid.
摘要 一种新的微生物分离物--黄杆菌 (Flavobacterium sp.) 菌株 DS5 能将亚油酸转化为 10-hydroxy-12(Z)-octadecenoic acid (10-HOA),产率为 55%。该产物通过气相色谱、气相色谱/质谱、核磁共振和傅立叶变换红外光谱进行了表征。10-HOA 的比旋光度为 [α]D24=-5.58 (甲醇)。生产 10-HOA 的最佳时间、pH 值和温度分别为 36 小时、7.5 和 20-35°C。将亚油酸转化为 10-HOA 的酶是可溶性的,位于菌株 DS5 的细胞内。此外,还发现了两种次要产物,即 10-甲氧基-12-十八烯酸和 10-酮基-12-十八烯酸。菌株 DS5 对 10-HOA 进行了进一步代谢。在所研究的不饱和脂肪酸中,DS5 酶的反应性顺序为油酸>棕榈油酸>亚油酸>亚麻酸>γ-亚麻酸>肉豆蔻油酸。