Current Projects

Optimization of Biovanillin Conversion from Lemongrass Biomass Leaves Hydrolysate by Phanerochaete chrysosporium.

 Submerged fermentation was conducted to a one-step biovanillin conversion process using wild type strain of Phanerochaete chrysosporium belonging to the family Basidomycete. Primary screening has supported maximum biotransformation of ferulic acid to vanillin by using ammonium chloride and yeast extract as inorganic and organic nitrogen source respectively. Further improvements were studied using 2-level Factorial Design. Hydrolysate of lemongrass leaves containing enriched medium of ferulic acid (1.0 g/L) was used as main precursor. Seven variable factors with respect to vanillin production; ammonium chloride (65 – 85 mM), yeast extract (2 – 6 mM), temperature (25 – 45°C), pH (4.0 – 8.0), incubation time (12 – 48 hr), agitation (100 – 200 rpm) and inoculum size (6 – 9% v/v). A total of 70 run of experiments containing six replicates at centre points were employed. The significance of the experiment was evaluated by variance analysis (ANOVA). The model gave F-value of 58.02 with P-value of the model (P<0.0001), implying its significance. The regression coefficients and determination coefficient R2 for the linear regression model of vanillin production was 0.9956. These values indicate that the model comprehended a 99.56% of data variability. The adjusted determination coefficient (Adj R2= 0.9784) was also satisfactory to confirm the significance of the model. Under statistically optimum conditions vanillin production from ferulic acid by Phanerochaete chrysosporium was 0.192g/L with a molar yield of 24.5%.