Analysis of theMAT1-1andMAT1-2Gene Ratio in Black Koji Molds Isolated from Meju.
Aspergillus luchuensisis known as an industrially important fungal species used for making fermented foods such as awamori and shochu in Japan, makgeolli and Meju in Korea, and Pu-erh tea in China. Nonetheless, this species has not yet been widely studied regarding mating-type genes. In this study, we examined theMAT1-1andMAT1-2gene ratio in black koji molds (A. luchuensis,Aspergillus niger, andAspergillus tubingensis) and inAspergillus welwitschiaeisolated from Meju, a fermented soybean starting material for traditional soy sauce and soybean paste in Korea. The number of strains with theMAT1-1locus was 2 of 23 (A. luchuensis), 6 of 13 (A. tubingensis), 21 of 28 (A. niger), and 5 of 10 (A. welwitschiae). Fungal speciesA. tubingensisandA. welwitschiaeshowed a 1 : 1 ratio ofMAT1-1andMAT1-2mating-type loci. In contrast,A. luchuensisrevealed predominance ofMAT1-2(91.3%) andA. nigerofMAT1-1(75%). We isolated and identified 2A. luchuensisMAT1-1 strains from Meju, although all strains for making shochu in Japan are of the MAT1-2 type. These strains may be a good resource for breeding ofA. luchuensisto be used in the Asian fermented-food industry.
Korean Agricultural Culture Collection, Agricultural Microbiology Division, National Institute of Agricultural Science, Wanju 55365, Korea.
Anbazhagan
A
Mageswari
Korean Agricultural Culture Collection, Agricultural Microbiology Division, National Institute of Agricultural Science, Wanju 55365, Korea.
Jeong-Seon
JS
Kim
Korean Agricultural Culture Collection, Agricultural Microbiology Division, National Institute of Agricultural Science, Wanju 55365, Korea.
Kyu-Ho
KH
Cheon
Korean Agricultural Culture Collection, Agricultural Microbiology Division, National Institute of Agricultural Science, Wanju 55365, Korea.
Soon-Wo
SW
Kwon
National Research Institute of Brewing, Higashi-hiroshima, Hiroshima 739-0046, Japan.
Osamu
O
Yamada
Korean Agricultural Culture Collection, Agricultural Microbiology Division, National Institute of Agricultural Science, Wanju 55365, Korea.
Seung-Beom
SB
Hong
Aspergillus luchuensis; Mating type; Meju