Several species of the fungi were isolated from cassava(Manihot esculenta Gruntz) starch which had formed into pellet, those had been stored for a while in southern part of Thailand. The species of Rhizopus, Aspergillus niger, and Aspergillus fumigatus were identified.
The experimental results are as follows;
Dry weight increases were checked during the static liquid culture with modified Czapek Dox medium to which cassava starch was partly replaced to sugar, Aspergillus niger and Aspergillus fumigatus had grown more than Rizopus species when 6% cassava starch was replaced to sugar and had been cultured for 72 hours.
Amounts of mycelial protein of Aspergillus niger were checked, the highest amount was shown in 6% cassava starch involved medium.
When nitrogen sources were varied such as ammonium sulfate or urea against sodium nitrate, there was no significant difference in mycelial production.
Alpha amylase activity of each fungus isolated here was checked, those of Aspergillus niger have shown the highest peak at 72 hours.
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