The distribution of the ochratoxin producing species of Aspergillus section Nigri in a vinery and the productive capacity of the isolate strains

摘要

SummaryThere is no report in Japan about the frequency of the ochratoxin producing strains on Aspergillus section Nigri and the distribution of the producing species. The surveillance study is needed for ochratoxin producing species based on the detailed classification of Aspergillus section Nigri. As a result of the investigation in Yamanashi, although most of A. niger (DNA type; AN-D-5 and AN-D-7) did not produce ochratoxin, a strain of AN-D-5 did slightly produce ochratoxin. A. carbonarius is a main ochratoxin produce species in Aspergillus section Nigri, it produce much ochratoxin A and show DNA type AN-D-4. However, some strains did not produce ochratoxins accoding to culture same conditions. Most of vineyard soil and the fungus of air born were A. japonicus (DNA type AN-D-1 and AN-D-2), and A. niger (DNA type AN-D-5 and AN-D-7), A. carbonarius of DNA type AN-D-4 was one share among 129 strains from soil. This isolate frequency was very low. If management after harvest is performed proper, it will be thought that there is very little contamination to food.