Journal of Fisheries and Life Sciences

Author(s): Md. Lemon Mia, Md. Ahsan Bin Habib, Md. Mijanur Rahman, Nazmul Hoque, Md. Saiful Islam, Abdulla-Al-Asif

Abstract: A study was conducted to examine the culture and growth performance of S. platensis in three different concentrations (25%, 50% and 100%) of digested liquid rice starch media (DLRSM) with 0.2 g/L urea and Kosaric medium (KM) as control for a period of three months from March to May 2018. Each experiment was done in triplicates for a period of 14 days. The growth rate of S. platensis was found to vary with different concentrations of the medium. The cell weight of S. platensis was attained to highest 12.42 mg/L (dry weight) in KM followed by 11.26 mg/L, 8.35 mg/L and 9.11 mg/L in 25%, 50% and 100% of DLRSM, respectively on the 10^th day of culture period. Similar trend also observed in case of chlorophyll a content of S. platensis. The proximate composition of rice starch was analyzed. The percentage of moisture, protein, lipid, ash, crude fiber and nitrogen free extract (NFE) were95.1, 0.2616, 0.1055, 0.1097, 0.1468 and 3.9669, respectively on the basis of moisture (%) and 4.59, 5.70, 2.30, 2.39, 3.20 and 86.41, respectively on the basis of dry matter (%). The results on the growth performance showed that the growth of S. platensis was significantly (P<0.01) higher when grown in 25% concentration of DLRSM than other concentrations in 50% and 100% of DLRSM. The physico-chemical parameters viz. light intensity (2685 to 2773 lux/m²/s), temperature (29.6 to 31.5°C), pH (8.3 to 9.9), alkalinity (1150 to 3032 mg/L), Nitrate-N (1.32 to 6.30 mg/L) and phosphate-P (9.75 to 61.50 mg/L) were within optimum level during the culture period.