IDENTIFICATION OF MOLECULES AND GAS CHROMATOGRAPHY- MASS SPECTROMETRY EVALUATION OF SECONDARY METABOLITES DERIVED FROM THE ENDOPHYTE KUSHNERIA AVICENNIAE OBTAINED FROM AVICENNIA MARINA (FORSSK.) VIERH, AND A COMPARATIVE ASSESSMENT OF ANTIBACTERIAL PR

Objectives: This research aimed to evaluate the antibacterial effects of solvent extracts obtained from the flowers of Avicennia marina (Forssk.) Vierh and its endophyte, Kushneria avicenniae, and to analyze the bioactive compounds produced by the endophyte. Methods: This research gathered flowers from the mangrove species A. marina (Forssk) Vierh in Manakudi village, located in the Ramanathapuram district of Tamil Nadu. The flowers underwent surface sterilization, followed by the isolation of an endophyte using a Starch casein agar medium. The antibacterial properties of various solvent extracts from the flower and its endophyte were evaluated against Listeria monocytogens ATCC 19115 and Escherichia coli ATCC 25922 using the well diffusion method. The isolated endophyte was identified through genotypic methods, and gas chromatography-mass spectrometry was employed to analyze the bioactive compounds produced by this endophyte. Results: The different solvent extracts of the flower of the mangrove A. marina (Forssk) Vierh showed no inhibition zone for the pathogens, and the extract of the bacteria showed an inhibition zone of 11 mm for E. coli ATCC 25922 and 12 mm for L. monocytogenes ATCC 19115. The endophyte was identified as K. avicenniae. The gas chromatography- mass spectrometry analysis detected the presence of nearly 40 potential bioactive compounds. Conclusion: This study emphasised the importance of exploring the mangrove ecosystem and its relatively understudied endophytes, capable of producing secondary metabolites with distinctive features and bioactivities.