Antioxidant and antimicrobial efficacies of Amaranthus polygonoides and its impact on L-asparaginase production

Abstract

Traditional medicinal herbs play a vital role in primary healthcare throughout the world. The current investigation represents the analysis of antioxidant, antimicrobial activities of Amaranthus polygonoides and its application in L-asparaginase (anti-leukemic enzyme) production. The plant leaves were dried and extracted with distilled water to yield their crude extracts. Further, this extract was subjected to screening of antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method and nitric oxide scavenging activity. The extract was found to have the highest DPPH free radical scavenging activity (84%) and nitric oxide scavenging activity (71.8%). Moreover, the extract was proved to be active against Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Klebseilla pneumonia, Aspergillus niger and Aspergillus fumigatus through antimicrobial activity test. After the initial assessment, the extract was screened for the production of L-asparaginase by Streptomyces venezuelae using rapid plate assay and confirmed the enzyme production by zone formation. The effect of concentration of A. polygonoides leaves extract on specific growth rate and specific L-asparaginase production rate was evaluated thorough Monod kinetics and the maximum specific growth rate, μm and maximum L-asparaginase production rate, P_m were found to be 0.8683 and 0.7902 h^-1, respectively.

Keywords: Amaranthus polygonoides, antioxidant, L-asparaginase, production kinetics