Producing biodiesel from cottonseed oil using Rhizopus oryzae ATCC #34612 whole cell biocatalysts: Culture media and cultivation period optimization

• Immobilized microbial whole cells with surface active lipases as biocatalysts.
• Lipases as biocatalysts suitable for biodiesel production.
• Supplementing culture media with oil or glucose enhances conversion efficiency.
• R. oryzae immobilized on novel polyethylene supports can allow for easier scale up.
• Optimizing process parameters to increase immobilized biomass and lipase activity.

The effect of culture medium composition and cultivation time on biodiesel production by Rhizopus oryzae ATCC #34612 whole cell catalysts, immobilized on novel rigid polyethylene biomass supports, was investigated. Supplementation of the medium with carbon sources led to higher lipase activity and increased the biomass immobilized on the BSPs. Statistical analysis indicates that a cultivation period of 72 h in a basal medium supplemented with both cottonseed oil and glucose is optimal for biodiesel production by R. oryzae, resulting in a fatty acid methyl ester (FAME) yield of 27.9 wt.% (228.2 g/L).