L-Asparaginase from yeast and its potential as anti-cancer: optimization of production, purification, and medical applications

Abstract

L-Asparaginase is an important enzyme which converts L-asparagine to L-aspartate and ammonia. The microbial L-asparaginase had important applications in the development of biosensors and as anticancer and food processing agents. In this study, seventeen yeast isolates were isolated from different sources including (Egyptian clover flower honey, Nigerian honey, banana peel, yoghurt, grape, sugar-cane bagasse, and soil). These yeasts with other three yeast isolates; were purchased from Northern Regional Research Laboratory(NRRL), were assayed for the qualitative and the quantitative production of L-asparaginase. The results revealed that the yeast isolate (Ba) isolated from banana peel was the most potent L-asparaginase producer havingthe highest pink zone diameter(47±2.20 mm), and also the highest specific activity (3059±193 U/mg protein). Hence, it was chosen for further studies. The yeast isolate (Ba) was identified as Kodamaea ohmeri ANOMY based on the analysis of nuclear large subunit (26S) ribosomal DNA partial sequences. Other five yeast isolates were identified using Vitek 2 system.Yoghurtisolate (Y)was identified as Candida krusei,sugar-cane bagasseisolate (B2)was identified as Candida tropicalis,sugar-cane bagasseisolate (B1)was identified as Candida famata,grapeisolate (G) was identified as Cryptococcus laurentii, and Nigerian honey isolate (Sh15)was identified as Candida guilliermondii.