| dc.description.abstract | Biofloc technology (BFT) is characterized by adjusting C/N ratio to control excessive nitrogen buid up. It has been known that the formation and quality of bioflocs depend upon the source of supplementary organic carbon. In this present study effluent from intensive shrimp pond in Vung Tau was used for biofloc formation using three different carbon sources, namely molasses (19.53%C), corn meal (44.1%C; 1.52%N), and food-graded sugar (40.22%C). No significant difference of total ammonia nitrogen (TAN) reduction was found between three different carbon sources (p>0.05). However, the rate of reduction was higest in the mollasses treatment and lowest in the food-graded sugar treatment. A significant difference in suspended solid (SS) was observed between molasses and sugar, and between corn and sugar (p<0.05). While volatile suspended solid (VSS) was significantly differred from corn to molasses and sugar (P=0.039). Statistical analysis revealed that floc volume index (FVI) was different between corn and molasses (P=0.028); between corn and sugar (P=0.029) while molasses and sugar were not contribute any significant difference. There were six bacterial strains were identified from the flocs formed in all treatment. Among them, Citrobacter freundii and Klebsiella pneumoniae were able to catalyse biotransformation of nitrogenous compound. Beside, Pseudomonas nitroreducens is able to synthesise polyhydroxybutyrate homopolymer. Three other strains seemed to be derived from water medium.
Key words: bioflocs technology, floc volume, nitrogenous compound, organic carbon
source. | en_US |
