Identification of Asp. toxicarius and Some Other Aspergilli

Taxonomic Studies on Japanese Industrial Strains of the Aspergilli (Part 35)

Abstract

A strain NJK 4044 (=RMF 7133 of M. Christensen, IFO 31250) was a typical strain of Aspergillus toxicarius Murakami and produced aflatoxins remarkably by fluorescence test using APA-medium. Two strains preserved for a long time under the name of A. candidus in a maker of tane-koji (mold starter) in Japan was proved to belong to A. oryzae var. brunneus.
Among the 27 strains identified formerly with A. oryzae var. viridis about a half of them lost any green hue in their conidial heads when incubated at 30° for 25 days which were now placed in the other varieties, and a half of the remains kept this hue even after 100 days culture which showed characteristically broom-like to columnar types of conidial heads, and the results were shown in Table 102. Relations between the types and colors of conidial heads were shown in Table 104, and about 80% of the strains of broom-like to columnar types kept the green hue. The key character of the color of conidial heads, however, could not be replaced with that of the type of them from any view points.
A type culture of A. oryzae var. viridis was assigned to a strain RIB 128 in 1971, which has also been called IFO 30113, ATCC 22788 and CBS 819. 72 and is preserved in Nippon Jozokyokai as NJK 128 since 1975 showing some metulae until now. However, this strain was placed from now in A. oryzae var. oryzae because of its metulae, and then a lectotype, NJK 72, was determined as a correct type culture which was isolated by Murakami in 1953 from commercial tane-kojis for the brewing of sake and shoyu.