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Endophytic microbes are sources for the novel antibiotic. We isolated endophytic bacteria from Zingiberaceae collected from West Sulawesi, Indonesia, and investigated their anticandidal activity. Molecular identification of the isolates was done using 16S rRNA gene sequence analysis. The antimicrobial activity was tested against four bacteria and one yeast. The anticandidal compound of selected bacteria was extracted using three different solvents (chloroform, ethyl acetate, and methanol), and each fraction was tested for their anticandidal activity. Anticandidal minimum inhibitory concentration (MIC) was determined with concentration ranging from 300 to 18.75 μg/mL, and the morphology of the Candida cells after treatment was confirmed by scanning electron microscope (SEM). The identification of anticandidal compounds was conducted using GC-MS. A total of 24 isolates were collected from Zingiberaceae plants. There were 14 genera and 19 species belonging to Gammaproteobacteria (66.67%), Alphaproteobacteria (25.00%), Actinobacteria (4.17%), Bacteriodetes (4.17%), and a new record for Lelliottia aquatilis as an endophytic bacteria. One of 24 isolates identified as Pseudomonas helmanticensis isolated from Alpinia melichroa showed anticandidal activity. Ethyl acetate was the appropriate solvent to extract the anticandidal compounds. Diisooctyl phthalate was found as the most abundant compound in the extract for the anticandidal activity. An increase in extract concentration did not reduce the Candida cell number. The extract treatment showed membrane disruption of Candida albicans cells. We propose that active compounds from P. helmanticensis are potential as anticandidal sources and could be explored more for the pharmaceutical industry.

Several bacteria were isolated from straw mushroom ( Volvariella volvacea ) cultivation medium. There are three potential isolates previously characterized and has growth inhibition effect against V. volvacea . This screening result lead to the further study about the inhibition activity against phytopathogenic fungi. The aim of this research is to investigate the antifungal activity of three bacterial isolates against three phytopathogenic fungi and identification of the bacteria. The method used in this study are antifungal assay using co-culture method and disk difussion assay using the filtrate of each bacteria. The profile of antifungal compound was identified using ethyl acetate extract followed by evaporation and gas chromatography (GC-MS) analysis. Identification of each isolates was performed using 16S rDNA amplification and sequencing. Three phytopathogenic fungi i.e Cercospora lactucae (InaCC F168), Colletotrichum gloeosporides (InaCC F304) and Fusarium oxysporum f.sp. cubense (F817) were co-cultured with bacterial isolates C2.2, C3.8, and D3.3. The C3.8 isolate has highest average inhibition activity either using isolate and filtrate. The result relatively consistent against three phytopathogenic fungi. The metabolite profile of C3.8 isolate showed the Bis(2-ethylhexyl) phthalate as the main compound with 97% similarity. Bis(2-ethylhexyl) phthalate has potential effect as antibacterial and antifungal compound. According to EzBioCloud and GeneBank databases, the C2.2 isolate identified as Bacillus tequilensis , C3.8 as Bacillus siamensis and D3.3 as Bacillus subtilis subsp. Subtilis . This study also shows the potential of Bacillus siamensis C3.8 as biocontrol against phytopathogenic fungi.