Strong potential of white cambodia (Plumeria acuminata) phyllosphere bacteria which inhibit Candida albicans growth

Abstract

Candida albicans is the most common fungal species that infect humans. Over time pathogenic fungi can evolve to become more resistant to current antimicrobials. Therefore, the search for new antimicrobials needs to be carried out continuously. White cambodia leaves (Plumeria acuminata) contain several secondary metabolite compounds with antimicrobial properties. The leaf surface is a habitat for microbes such as phyllosphere bacteria, which are known to have the ability to produce secondary metabolite compounds that are the same as the host where they live. This study aims to determine the antifungal potential produced by P. acuminata phyllosphere bacterial isolates in inhibiting the growth of C. albicans. This research uses experimental laboratory methods. The initial stage was the isolation of P. acuminata phyllosphere bacteria using the serial dilution method. After that, observation of colony characteristics based on shape, edge, elevation, texture, and pigment, as well as Gram staining of P. acuminata phyllosphere bacterial isolates. The final stage was an antagonistic test of phyllosphere bacterial isolates against C. albicans using the two-layer agar method. Isolation of P. acuminata phyllosphere bacteria produced 151 isolates, and 66 isolates were selected as samples. Based on the observation of isolate characteristics and morphology of bacteria from 66 isolates, the isolate characteristics and morphology of bacteria were diverse. Based on the Gram staining test, it is known that Gram-positive bacteria in the form of cocci are dominant. Fourteen isolates of phyllosphere bacteria could inhibit the growth of C.albicans based on the results of the antagonist test. White Cambodia (P. acuminata) phyllosphere bacterial isolates can produce antifungal compounds inhibiting C. albicans growth.