ISOLATION, IDENTIFICATION AND SELECTION OF MOLD STRAINS WITH HIGH PROTEASE ACTIVITY FROM LOTUS SEEDS

Abstract

The study was carried out with the aim of isolating and preliminary identifying some Aspergillus species found on lotus seeds in Thap Muoi market, Dong Thap province to select strains with high protease biosynthesis ability to apply in the process soy sauce production. The results showed that lotus seeds have a high frequency of fungal isolation. From samples of lotus seeds collected at market stalls, four mold strains with symbols MS1 - MS4 were isolated. Isolated fungal strains were identified by morphology and identified to the species level by ITS region gene sequencing. The MS1 - MS3 strain was identified as Aspergillus flavus with 99,89 - 100% similarity and the MS4 strain was identified as Aspergillus tamarii with 100% similarity. The results of surveying protease enzyme activity according to culture time showed that the Aspergillus tamarii strain had the highest activity at 72 hours of culture, reaching 1153,67 UI/g.