Aspergillus nomius is described and represents a new aflatoxigenic species phenotypically similar to A. flavus. Strains examined were isolated from insects and agricultural commodities. Separation from A. flavus is based on the presence of indeterminate sclerotia and a lower growth temperature. Comparisons of DNA relatedness show A. nomius to have only relatively recently evolved from A. flavus and A. tamarii.

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A method has been developed for the production of aflatoxin by growing Aspergillusflavus strain NRRL 2999 on the solid substrate rice. Optimal yields, more than 1 mg of aflatoxin B1 per g of starting material, were obtained in 5 days at 28 C. A crude product containing aflatoxins was isolated by chloroform extraction and precipitation with hexane from concentrated solutions. The crude product consisted of 50% aflatoxin in the following ratio: B1-B2-G-G2, 100:0.15:0.22:0.02. Aflatoxin B1 was separated from almost all the impurities and from the other aflatoxins by chromatography on silica gel with 1% ethyl alcohol in chloroform. Analytically pure aflatoxin B1 was recrystallized from chloroform-hexane mixtures.

Marine chlorella known to contain high amount of eicosapentaenoic acid (20:5co3) are a potential natural source of this fatty acid for health foods and pharmaceuticals. The effect of culture conditions on lipid content and fatty acid composition of Cblorella minutissima, therefore, was investigated. Lipid content of cells grown at 25 C was 60% higher than that of the cells grown at 20 C. Fatty acid composition was affected by culture temperature and supplementation of NaC1. Eicosapentaenoic acid 20:5co3 content was 45% (w/w) in the cells grown at 20 C, whereas that of the cells grown at 25 C was only 20% (w/w). Supplementation with NaCI also increased the percentage of 20: 5¢o 3 acid to the same extent.

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A B S T R A C TThe various ethnic groups of the Darjeeling district of West Bengal and Sikkim consume a variety of fermented foods including kinema (based on soya beans), gundruk (Brassica campestris leaves), sinki (radish, Raphanus sativus), mew (bamboo shoots), churpi (milk), shel roti (rice preparation) and jnards (beers). These have not previously been investigated, and their method of preparation and consumption are reported here. The jlora of murcha, the starter culture of jnards, contains mainly Pediococcus, yeasts belonging to the genera Saccharomycopsis, Pichia and Saccharomyces and the moulds Rhizopus and Mucor.

Resting cell suspensions of seven Nocardia species catalyzed the production of 10-hydroxystearic acid from oleic acid. Nocardia cholesterolicum N R R L 5767 gave a good yield with optimum conditions at pH 6.5 and 40 ° C. Yields exceeding 90% can be obtained within 6 h with 0.1 g cells (dry weight) and 178 mg oleic acid in 10 ml of 0.05 M sodium phosphate buffer (pH 6.5). In addition, minor amounts of 10-ketostearic acid were formed as a by-product. The reaction proceeded via hydration of the double bond as shown by labeling experiments with deuterium oxide and 180-labeled water. The system was specific for fatty acids with cis unsaturation at the 9 positon.

Fusarium equiseti NRRL 5537 grown on an autoclaved white corn grit medium for 3 to 4 weeks at room temperature produced a substance in excess of 5 g/kg of substrate that inhibited some gram-positive bacteria including mycobacteria. Most Bacillus subtilis, Mycobacterium phlei , and Staphylococcus aureus strains were inhibited when 1 μg of the antibiotic per ml was incorporated into the culture medium. Except for Neisseria perflava , gram-negative bacteria, yeasts, and molds were not inhibited by 128 μg/ml. The antibiotic was recovered as a white powder, had a melting point of 65 to 66 C, and had an intraperitoneal mean lethal dose in white mice of 63 mg/kg of body weight. In thin-layer chromatographic analysis the compound appeared as a single spot in two different solvent systems. Mass spectrometry determined that the molecular weight of the antibiotic was 373 with a molecular formula of C 22 H 31 NO 4 . Chemical microanalysis was in accord with the formula.