Culture and production of spirulina (Spirulina platensis) in supernatant of digested rotten potato

An experiment was conducted to evaluate culture and growth performance of spirulina(Spirulina platensis) in supernatant of three different amount of digested rotten potato (DRP), andKosaric medium (KM) as control. Three different concentrations such as 25, 50 and 75% of DRPwere digested under aeration and the reddish white coloured supernatant was collected. Spirulinawas inoculated in supernatant of DRP with the addition of 9.0 g/L NaHCO3 and micronutrients,and KM for a period of 14 days. The cell weight of spirulina was attained a maximum of 11.48±1.25 mg/L in KM followed by 11.46±1.03, 9.16±0.84 and 8.13±0.73 mg/L in supernatantof 50, 25 and 75% DRP, respectively on the 10th day of culture. Similar trend was also observedin the cases of optical density, chlorophyll a, total biomass, specific growth rates and totalbiomass of spirulina. Cell weight of spirulina grown in these media had highly significant(p<0.01) correlation with the chlorophyll a content and total biomass. The growth performanceof spirulina grown in supernatant of 50% DRP was significantly higher than that of spirulinagrown in supernatant of 25 and 75% DRP. The percentage of crude protein (55.15%) of spirulinagrown in supernatant of DRP was little bit lower than that of spirulina cultured in KM (58.70%).The crude lipids (17.15%) of spirulina cultured in supernatant of 50% DRP was almost two andhalf times higher than that of spirulina grown in KM (6.33%). It indicates that for the productionof spirulina with high lipid content, supernatant of DRP may be used. Therefore, mass culture ofS. platensis may be done in supernatant of 50% DRP.