Characterization of Exopolysaccharides Produced by Bacillus cereus and Brachybacterium sp. Isolated from Asian Sea Bass (Lates calcarifer)

Abstract

Aims: EPS extracted from marine bacteria, which associated with Asian sea bass has potential antimicrobial activities. Methodology and Results: Two marine Bacteria were isolated from Asian sea bass (Lates calcarifer) obtained from aquaculture farm, located at Johor bahru Malaysia. 16S rRNA analysis for bacteria identity revealed that bacteria ors1 had 99 % identity to Bacillus cereus and ors2 had 96 % identity with Brachybacterium sp. All bacteria shared many similarities and variation in terms of biochemical reactions and microscopic observation. Exopolysaccharides (EPSs) were extracted and purified from bacteria as they produced mucous colonies. Average analysis of EPS components showed 50 % carbohydrates, 26 % protein and 24 % fatty acids. The FTIR analysis confirmed the functional groups of the EPS. Screening for antimicrobial activities assays using Kirby-Bauer methods against both grams positive and negative had shown presence of inhibition zones. Conclusion, significance and impact of study: This study recommends that bacteria isolated from Asian sea bass are having antimicrobial activities and could be used as a potential source for the development of marine drugs.

Effect of Salinities on Gastric Emptying and Nutrient Absorption of Tiger Grouper × Giant Grouper (Epinephelus fuscoguttatus × E. lanceolatus) Hybrid

“…This is due to the fact that the pellet contained relatively low carbohydrate content and lead to lower energy value. This has been observed for example in Asian sea bass Lates calcarifer (Orsod et al 2012), white bream Blicca bjoerkna (Cara et al 2003) and black seabream Pagellus bogaraveo (Ribeiro et al 2008). Besides that, the patterns for energy removal closely followed the pattern for lipids.…”

Capillary electrophoresis of microbial aggregates

“…The p I of ≥ 3.6 for B. cereus and E. coli bacteria suggests the presence of an additional protein layer. According to previous research, B. cereus , Bacillus antracis , and Bacillus brevis are surrounded by an S ‐layer composed of protein or a mucous coating, which consists of extracellular polymeric substances (26–40% protein) . In E. coli , this phenomenon can be explained by the presence of lipoproteins, porins, and large numbers of protein appendages (flagella, fimbriae, pili) on the surface of the outer membrane.…”

Production and Characterization of Exopolysaccharide From Marine Moderately Halophilic Bacterium Halomonas Smyrnensis SVD Iii

“…Optimization of different nutrient media for the production of EPS by Bacllus subtilis has been described [20]. Characterization of EPS produced by Bacillus cereus and Brachybacterium species was carried out [18]. Production of EPS by alkalitolerant and halotolerant Vagococcus carniphilus isolated from alkaline soda lake of Lonar, India was described, production of EPS was optimized for different environmental conditions and characterized the EPS for total carbohydrate content and monosaccharides [21].…”

“…The purified EPS was characterized using fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) [6,12,18,31].…”

“…Many Bacillus species are reported for EPS production [16][17][18][19][20]. Production of EPS from alkaliphilic Vagococcus carniphilus was investigated [21].…”