Entomopathogenic fungi Beauveria sp. and Aspergillus sclerotiorum can produce secondary metabolite quinidine

Abstract

Entomopathogenic fungi have been reported to produce secondary metabolite quinolines. One of the quinoline alkaloids is quinidine, a compound that has antiarrhythmic properties, therefore it has an economic important value. The aim of the experiment reported here was to study the potency of entomopathogenic fungi Beauveria sp. IPBCC. 19.1499 and Aspergillus sclerotiorum IPBCC.19.1500 in producing quinidine. The quinidine was obtained from a broth culture of each fungus grown in Potato Dextrose Broth medium (pH 6.2, static, room temperature) for 7, 14, and 21 days incubation period. At harvest, broth of each culture was extracted using chloroform. The extract then dried using an evaporator. The presence of quinidine in the extracted was detected by HPLC. The dry weight of fungal biomass and the crude extract of broth culture were also recorded. HPLC analysis showed that quinidine was produced by both fungi tested. The species of the fungus and incubation period significantly affected quinidine production. Beauveria sp. IPBCC.19.1499, in general, produced quinidine in higher concentration than that of A. sclerotiorum IPBCC.19.1500. The quinidine concentration increased significantly with increasing incubation period. The quinidine concentration was also positively correlated with biomass dry weight, while the crude extract dry weight was negatively correlated with quinidine concentration.