Abstract

ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES OF L-GLUTAMINASE FROM SEAWEED ENDOPHYTIC FUNGI PENICILLIUM CITRINUM

N. Sajitha*, S. Vasuki and M. Suja

ABSTRACT

The present study was aimed to evaluate the antibacterial and free radical scavenging activity of L-glutaminase enzyme extracted from seaweed endophytic fungi Penicillium citrinum. In human pathogens the enzyme showed maximum zone of inhibition in Vibrio parahaemolyticus (19.19±0.28 mm) and minimum zone of inhibition in Staphylococcus aureus (10.73±0.77 mm). In fish pathogens maximum zone of inhibition was observed in Edwardsiella tarda (17.47±0.42 mm) and the minimum zone of inhibition in Proteus sp. (10.34±0.31 mm). The total antioxidant activity of glutaminase enzyme was 61.51±0.23%. The IC50 value of enzyme for DPPH, reducing power, nitric oxide, hydroxyl radical scavenging activity was found to be 94.65, 117.73, 87.266 and 105.62 μg/ml respectively. The IC50 value of the enzyme was compared with standard ascorbic acid. The enzyme was found to scavenge free radicals generated in vitro and these findings indicated L-glutaminase as a potent antioxidant. The present study revealed that seaweed endophytic fungi are potential sources of microbial glutaminases exhibiting both antibacterial and antioxidant properties.

Keywords: Seaweed, endophytic fungi, glutaminase, antibacterial and antioxidant activities.