Antimicrobial activity of fungi isolated from the marine sponges collected from Sekotong Beach Lombok, Indonesia

Abstract

The search for new antibiotics from a variety of sources that have the potential to produce bioactive metabolite compounds is essential to solve the increasing problem of microbial resistance. Recently, one of the most widely studied for new antimicrobial sources is marine derived fungi. The aims of this study were to isolate endophytic fungi of marine sponges collected from Sekotong Beach Lombok, Indonesia and determine their antimicrobial activity. Fungi isolation were conducted in yeast extract, peptone, and dextrose (YPD) agar medium and each pure fungi was fermented for 21 days in YPD broth medium. Culture media and mycelium were separated by filtration method. The culture media was extracted by liquid liquid extraction and mycelium was extracted by maceration method using ethyl acetate. The dried extracts then tested for their antibacterial activity against Escherichia coli ATCC8739, Staphylococcus aureus ATCC6538, and Candida albicans ATCC 10231 using paper disk diffusion method. Extracts which showed antimicrobial activities on 250 ug/disk content were determined their minimum inhibitory concentration (MIC) and minimum bactericidal or Fungicidal concentration (MBC or MFC). The results of this research were obtained 12 fungi isolates that were coded as FSKT1 until FSKT12. The lowest MIC and MBC value against E. coli was showed by mycelium extract of FSKT10 with concentration of 128 and 256 ug/mL, respectively. The lowest MIC and MBC value against S. aureus was showed by medium extract of FSKT9 with concentration of 64 ug/mL and against C. albicans with concentration of 128 and 512 ug/mL, respectively. The antimicrobial activity observed in this research indicates that the endophytyc fungi of the marine sponge could be considered as new sources of antibiotics.