Ceratobasidium ramicola IBRLCM127, an endophytic fungus isolated from rhizome of local medicinal plant Curcuma mangga Valeton & Zijp was found to possess significant anticandidal activity. This fungal endophyte was cultivated in submerged fermentation system using Yeast sucrose medium supplemented with host plant water extract and cultivated at 250 C, agitated at 120 rpm for 12 days. The ethyl acetate was used as a solvent to extract compounds in the fermentative broth. The fungal ethyl acetate extract showed significant inhibition zones against Candida albicans cells with the minimal inhibitory concentration (MIC) value of 2.5 mg/mL and exhibited yeastocidal activity. The time-kill curve study conducted at three different ethyl acetate concentrations (half MIC, MIC and 2MIC values) revealed that the growth of C. albicans cells were concentration dependent. Yeastostatic activity was shown at lower concentration and yeastocidal activity was shown at higher concentration. The structural degeneration of the C. albicans cells after treated with ethyl acetate extract were observed under the scanning and transmission electron microscopes and the results exhibited various cell deformities including severe damage of the cell extracellularly and intracellularly which led to cell death beyond repair, thus suggesting that the extract could be a potential antifungal agent.
Key words: Ceratobasidium ramicola IBRLCM127, endophytic fungus, anticandidal activity, Curcuma mangga, Candida albicans
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