Enhanced Vitamin B12 Production using <i>Chlorella vulgaris</i>

Abstract

Microalgae <em>Chlorella Vulgaris</em> is enriched in vitamin B12 and cobalt ion which is positioned in the center of the vitamin molecule. This study aimed to investigate how different concentrations of cobalt chloride salt affected the vitamin B12 production by utilizing CO₂ gas, to assess <em>C. vulgaris</em> biomass. Therefore, Bold's basal medium used as the medium and 0.5, 1.5, 2 and 2.5 μM cobalt chloride salt was added to <em>C. vulgaris</em> culture. Under four cobalt chloride salt treatments, the best growth rate was obtained at the 2 μM of cobalt chloride salt (0.186 + 0.07 g /L.d). CO₂gas was supplied by 5% CO₂ gas cylinder and fermented milk as a novel biological CO₂gas generator (CO₂,10%). Use of fermented milk is a practical approach for elimination of waste gas emission and converting CO₂into biomass. The results revealed that, in the presence of 5% CO₂gas, <em>C. vulgaris</em> vitamin B12 content at 2 and 2.5 μM cobalt chloride, were 166.23 ± 1.78 and 173.32 ± 4.23 μg /100 g of dry biomass (7 and 12% higher than control), respectively. However, under controlled condition (ambient air and 2 μM cobalt chloride) vitamin B12 content was 154.9 ± 1.14 μg / 100 g of dry biomass.