Open AccessAntimicrobial activity in cultures of endophytic fungi isolated from Garcinia species
Author(s) -
Phongpaichit Souwalak,
Rungjindamai Nattawut,
Rukachaisirikul Vatcharin,
Sakayaroj Jariya
Publication year - 2006
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.2006.00155.x
Subject(s) - biology , antimicrobial , microbiology and biotechnology , plant use of endophytic fungi in defense , microsporum gypseum , candida albicans , staphylococcus aureus , cryptococcus neoformans , minimum inhibitory concentration , garcinia , endophyte , botany , bacteria , trichophyton , antifungal , genetics
The aim of the present study was to screen for antimicrobial activity in endophytic fungi isolated from surface sterilized leaves and branches of five Garcinia plants, G. atroviridis , G. dulcis , G. mangostana , G. nigrolineata and G. scortechinii , found in southern Thailand. Fermentation broths from 377 isolated fungi were tested for antimicrobial activity by the agar diffusion method. Minimum inhibitory concentrations (MICs) were obtained for crude ethyl acetate extracts. Seventy isolates (18.6%) displayed antimicrobial activity against at least one pathogenic microorganism, such as Staphylococcus aureus , a clinical isolate of methicillin‐resistant S. aureus , Candida albicans and Cryptococcus neoformans . The results revealed that 6–10%, 1–2% and 18% of the crude ethyl acetate extracts inhibited both strains of S. aureus (MIC 32–512 μg mL −1 ), Ca. albicans and Cr. neoformans (MIC 64–200 μg mL −1 ), and Microsporum gypseum (MIC 2–64 μg mL −1 ), respectively. Isolates D15 and M76 displayed the strongest antibacterial activity against both strains of S. aureus . Isolates M76 and N24 displayed strong antifungal activity against M. gypseum . Fungal molecular identification based on internal transcribed spacer rRNA gene sequence analysis demonstrated that isolates D15 ( DQ480353 ), M76 ( DQ480360 ) and N24 ( DQ480361 ) represented Phomopsis sp., Botryosphaeria sp. and an unidentified fungal endophyte, respectively. These results indicate that some endophytic fungi from Garcinia plants are a potential source of antimicrobial agents.