Jann Gregg M. Juntarciego, Precious Jemimah D. Legayada, Andrea M. Lim (March 2013)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
Actinobacteria constitute one of the most dominant phyla of Kingdom Bacteria. They have long been identified as useful sources of antibiotics. The purpose of this study was to isolate and identify Actinobacteria associated with the sponge Spongia officinalis. Several samples of the sponge was collected from Sitio Danao Danao, Polopina, Conception, Iloilo and was taken back to the laboratory for the 10-fold dilution. 500 uL of the dilution was plated onto Starch Casein Agar plates using the spread plate method. After 3 weeeks of incubation under 28 degrees Celcius to 30 degress Celcius , the visible colonies were streaked onto Yeast Malt Agar plates using the streak plate method. The isolated bacteria were then stocked in Starch Casein Agar slants. The bacteria turned out to be gram-negative after the Gram-staining process. It appeared to have light yellow colonies which were waxy and shiny, a concaved and smooth surface, no distinct reverse side pigments, and dark, round pigments within it when subjected against the light. Under the 100x magnification of an oil immersion microscope, the bacteria showed long spore chains with coccoid cells. These results show that the bacteria we isolated from Spongia officinalis do not belong to phylum Actinobacteria and that the said sponge is not a substantial source for Actinobacteria.