稻曲病菌厚垣孢子脂肪酸组成的研究

【目的】为探明细胞壁和细胞内脂肪酸成分及含量与细胞抗逆性的关系,【方法】采用酸热法、索氏提取法、有机溶剂法对稻曲病菌的厚垣孢子壁进行脂肪酸提取,并采用气相色谱检测其脂肪酸的组成和含量。【结果】采用酸热法提取脂肪酸效果最好,以该方法提取测定稻曲病菌黄色、黄绿色、黑色厚垣孢子壁饱和脂肪酸相对含量分别为26.92%、17.23%、23.71%,其不饱和脂肪酸相对含量分别为60.46%、61.52%、70.64%;厚垣孢子总(沉淀孢子壁和上清液)饱和脂肪酸相对含量分别为28.87%、21.00%、24.04%,厚垣孢子总不饱和脂肪酸相对含量分别为55.43%、55.87%、63.89%。硬脂酸在厚垣孢子壁中的含量:黄色>黄绿色>黑色;不饱和脂肪酸中顺式-5,8,11,14,17二十碳五烯酸(EPA)在厚垣孢子壁的含量:黑色>黄绿色>黄色。【结论】在3种颜色厚垣孢子中,黑色休眠型厚垣孢子在孢子壁、总不饱和脂肪酸含量均最高,表明不饱和脂肪酸的含量提高,有利于厚垣孢子的休眠越冬。

Research on the composition of the fatty acids in chalmydospores of Ustilagioidea virens

[Objective] In order to investigate the relationship between the fatty acid composition and content and cell stress resistance in intracellular and cell wall. [Methods] In this study, three methods had been used for extracting the fatty acid from walls of chalmydospores, which were acid-heat method, soxhlet extraction and organic solvent, respectively. The fatty acid composition and content were detected by GC afterwards. [Results] Acid-heat extraction presented the best performance, by which the relative contents of saturated fatty acids in yellow, yellowish green and black chlamydospore walls were 26.92%, 17.23%, 23.71%, respectively, while unsaturated ones were 60.46%, 61.52%, 70.64%, separately. Further determination with the above same method, the relative total contents of 3 types of chlamydospores saturated fatty acids (precipitating wall plus supernatant) were 28.87%, 21.00%, 24.04%, separately and unsaturated ones with 55.43%, 55.87%, 63.89%, respectively. The content of stearic acid in saturated fatty acids in chlamydospore wall were yellow > yellowish green > black; the content of cis-5,8,11,14,17 eicosapentaenoic acid (EPA) methyl ester in unsaturated fatty acids in chlamydospore wall: black > yellowish green > yellow. [Conclusion] In all three colors of chlamydospore, either the total content of unsaturated fatty acids in spore or spore wall, the black showed the highest, which indicated that improving the content of unsaturated fatty acids in chlamydospores contributes to their dormancy and overwintering.