Keragaman Bakteri Endofit dari Akar Durian (Durio Zibethinus) dan Potensi Antimikrobanya

Abstract

Durian is a local Indonesian annual that has a high economic value. The presence of microbes plays a role in survival and contributes to the growth and survival of plants in nature. The microorganisms that live on durian play a role in protecting durian plants from pathogenic microbes. Information on the diversity, potency, endophyte bacteria, and secondary metabolite compounds of durian is currently limited. The study aims to identify the diversity of endophyte bacteria in the durian root and its antimicrobial potential. Endophyte bacteria were isolated from the roots of several durian varieties collected in the Madirsan Gardens of North Sumatra. Surface sterilized roots were inoculated into the Nutrient Agar medium. Endophyte bacterial isolates were subcultivated and characterized macroscopically and microscopically. The antimicrobial ability to isolate endophyte bacteria with varying macroscopic and microscopic characteristics was tested against four pathogenic microbes: Escherichia coli, Staphylococcus aureus, Methicillin-Resistant Staphylococcus aureus (MRSA), and Candida albicans. Fourty four endophyte bacteria isolates of with varying macroscopic and microscopic characteristics were obtained. Antagonistic tests showed seven isolates inhibiting E. coli, three isolates suppressing S. aureus, eight isolates preventing MRSA, and three isolates suppressing C. albicans. Based on molecular identification using specific bacterial primers 27F and 1492R, it was known the five potentitial isolates consisting of Myroides odoratimimus (BEM 4), Bacillus subtilis (BEMK 4), Bacillus cereus (BEO 2), Bacillus mycoides (BEK 1), and Stenotrophomonas malthophilia. (BEK 2). Ethyl acetate extract from the fermentation of the fifth isolate contains alkaloid and flavonoid compounds. Endofit bacterial ethyl acetic extract can inhibit test pathogens with a barrier zone diameter ranging from 12.3 mm to 28.3 mm.