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Recent progresses in the microbial production of vitamins and their related compounds were out lined. A new optical resolution process for racemic pantolactone, a chiral building block for the commer cial production of D-pantothenic acid, has been developed. In this optical resolution, a novel micro bial enzyme, lactonohydrolase, which was found in a fungus Fusarium oxisporum is used. The en zyme catalyzes hydrolysis of only the D-enantiomer in the racemic mixture. Thus, DL-pantolactone is easily separated into D-pantoic acid and L-pantolactone. Nitrile hydratase of Rhodococcus rhodochrous J1 catalyzes hydration of a various kind of ali phatic and aromatic nitriles. 3-Cyanopyridine, a starting substance for the commercial production of nicotinamide, is also efficiently converted to the corresponding amide, nicotinamide by the enzyme. Since the by-product formation from the produced nicotinamide, which is unavoidable in the conven tional chemical process, does not occur, the process using this enzyme is highly practical. The same organism produces nitrilase under the different culture conditions to those of nitrile hydratase produc tion. The enzyme is useful for the conversion of 3-cyanopyridine to nicotinic acid. Mycelia of a filamentous fungus Mortierella alpina 1 S-4 are practical source of triacylglycerols rich in arachidonic acid (AA). Under the suitable culture conditions, the oil accumulated by the fun gus reaches 500 〜 600 mg/g dry mycelia (13.5 g/l). The oil contains 30 〜 70%AA in the total fatty acids. Mutants derived from M. alpina 1 S-4 and defective in desaturases of AA biosynthesis are useful for the production of oils containing n-9 or n-3 polyunsaturated fatty acids.

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There are different biosynthetic pathways of the pyrimidine moiety of thiamin in Saccharomyces cerevisiae and Escherichia coli under aerobic and anaerobic conditions. The precursors of the pyrimi dine under anaerobic conditions have not been established. To elucidate the precursors of the pyrim dine under anaerobic conditions, the incorporation of the labels of following compounds, [2,2,3,3-D] succinate, [1-^<13>C]glycine and [2-^<13>C]glycine, into the pyrimidine was studied. The labels of [2,2,3,3-D]succinate were not incorporated into the pyrimidine under anaerobic con ditions in E. coli and S. cerevisiae. These results suggested that succinate had no relation to the bio synthesis of the pyrimidine. The labels of[1-^<13>C]glycine and [2-^<13>C]glycine were incorporated into C-4 and C-6 of the pyrimi dine respectively under anaerobic conditions as well as aerobic conditions in E. coli. We already reported that N atom of glycine, the precursor of N-1 of the pyrimidine under aerobic conditions, was incorporated into it under anaerobic conditions. These results showed that glycine was the precursor of the pyrimidine under anaerobic conditions as well as aerobic conditions.

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The fatty acid composition and vitamin E (E) content of 26 items of take-out lunch and eating-out including deep fried foods were measured. Many items analyzed were high in fat content, P/S ratio, and n-6/n-3 ratio. The same result was obtained on the items including fish. E content was higher in samples containing large amount of fat, but tocopherol (Toc)/PUFA (polyunsaturated fatty acid) ratio was constantly low. These results suggest that people who frequently eat take-out lunch or foods in eating-out should select their dishes carefully to prevent excess intake of dietary fat and unbalanced intake of fatty acids, that is, high in P/S or n-6/n-3 ratio and Toc/PUFA ratio.

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