Screening of Thermotolerant Microalgal Species Isolated from Western Ghats of Maharashtra, India for CO2 Sequestration

Abstract

Extensive work has been carried out to find suitable strain of algae which are tolerant to high concentration of CO2. In the previous studies Chlorella vulgaris (SAG 211.12), a mesophilic strain, showed CO₂ sequestration upto 23% CO₂ concentration. The main constraint using such strains is that they don’t tolerate temperatures beyond 35-40ºC. Hence attempts were undertaken to isolate algal strains from hot springs located across the western ghats of Maharashtra. Limnothrix redekei, Planktolyngbya crassa and Geitlerinema sulphureum could easily sequester about 28% of CO₂ without hampering biomass production. High temperature adaptability (42ºC), high CO₂ tolerance (23.08%), reasonably high biomass production and easy harvesting make G. sulphureum a promising candidate for the CO₂ sequestration in the tropical climatic conditions. Attempts are being made here to screen the isolated strains for lipid production.