Isolation and identification of polysaccharides derived from bacteria associated with sea cucumber, holothuria atra

Abstract

Marine bacteria from sea cucumber, Holothuria atra was isolated from the species of sea cucumber, Holothuria atra. Six bacteria colony were cultured and named as Hl, H2, H3, H4, H5 and H6. From all bacteria colony, only one bacterium was choose based on the pre-analysis to identify the possibility of the bacterium to produce high polysaccharide. The bacterium was identified as Brevundimonas diminuta based on morphology, biochemjcaJ tests and RapID™ NF Plus system. The bacterium has characteristics of Gram-negative bacteria, straight curved rod (coccobacillus) and from the Pseudomonas species. The purification of the polysaccharide from the bacterium was done to analyzed the chemical composition of sugar contains by the polysaccharide. The average yield of crude polysaccharides produced by the bacterium was 244.4mjlligram (mg) per 1 liter (L) and 81.2mg per IL for the acidic polysaccharides. Analyses of polysaccharide were done using the paper chromatograph (PC) and High Performance Liquid Chromatography (HPLC) techniques. The PC indicated the presence of glucose, lactose and raffinose. While HPLC showed the same results for glucose and lactose except the absence of raffinose. From the analyses, polysaccharide produced by Brevundimonas diminuta containing glucose, lactose and raffinose.