Optimization of 1, 3-Propanediol production by <em>Klebsiella pneumoniae</em> 141B using Taguchi methodology: Improvement in production by cofermentation studies

Abstract

In this study, 1,3-Propanediol production by isolated Klebsiella pneumoniae 141B strain using glycerol as a substrate has been investigated. Initial experiments were carried for the screening of nitrogen sources and yeast extract was found to be the optimum source. The impact of vitamin B12 on 1,3-PDO production was evaluated by growing the strain in vitamin B12 supplemented medium. One interesting phenomenon noticed that 1,3-PDO production was not increased by vitamin B12 supplementation, which aided in lowering the cost of fermentation process. Further optimization studies were carried out with six selected fermentation parameters such as pH, yeast extract, glycerol, calcium carbonate, inoculum size and temperature at three different levels. 1,3-PDO production has improved to 67% in Taguchi statistical optimization method. To further increase the 1,3-PDO production, cofermentation studies were carried out with the optimized medium having glucose and sucrose as co substrates.