Topic: Offer the oil and fat where dokosahekisaen acid content ratio increases.Solution expedient: sutoramenopairu possessing highly unsaturated fatty acid production talent, it features that it cultures with the nutrient medium which contains the substance which obstructs the fatty acid unsaturated conversion enzyme, the highly unsaturated fatty acid which is obtained by the production method and the said method of the highly unsaturated fatty acid, the oil and fat where especially dokosahekisaen acid content ratio increases. sutoramenopairu, it features that it cultures with the nutrient medium which contains the substance which obstructs the fatty acid unsaturated conversion enzyme, sutoramenopairu where the highly unsaturated fatty acid production talent which is obtained by the reinforcement method and the said method of highly unsaturated fatty acid production talent of sutoramenopairu was reinforced. Especially, it is the microbe where said sutoramenopairu is classified into the rabirinchiyura cord, production method of the said highly unsaturated fatty acid, reinforcement method of the said highly unsaturated fatty acid production talent, and sutoramenopairu where the said highly unsaturated fatty acid production talent was reinforced.課題:ドコサヘキサエン酸含有率の増加した油脂を提供すること。解決手段:高度不飽和脂肪酸産生能を有するストラメノパイルを、脂肪酸不飽和化酵素を阻害する物質を含有する培地で培養することを特徴とする、高度不飽和脂肪酸の製造方法、該方法により得られた高度不飽和脂肪酸、特にドコサヘキサエン酸含有率が増加された油脂。ストラメノパイルを、脂肪酸不飽和化酵素を阻害する物質を含有する培地で培養することを特徴とする、ストラメノパイルの高度不飽和脂肪酸産生能の増強方法、該方法により得られた高度不飽和脂肪酸産生能が増強されたストラメノパイル。特に該ストラメノパイルがラビリンチュラ綱に分類される微生物である、該高度不飽和脂肪酸の製造方法、該高度不飽和脂肪酸産生能の増強方法、および該高度不飽和脂肪酸産生能が増強されたストラメノパイル。
