In this present study, enzymatic esterification synthesis of fructose laurate was performed in organic media using lipase from Candida antarctica immobilized on acrylic resin. Screening phase of esterification reaction was done using two commonly used commercial immobilized lipases, in three different solvents, molecular sieve loadings, and reaction time to observe their effect on the yield of fructose laurate. The highest yield was obtained by using ethanol as the solvent, 0.02 g lipase loading, 0.10 g molecular sieves loading, and 24 hr of reaction time. By using response surface methodology (RSM) with central composite design (CCD), it was found that the optimum operational conditions were 40°C, 0.13 g lipase loadings, 200 rpm agitation rate, and without molecular sieve needed for the system. The optimized esterification conditions could give the yield of fructose laurate about 93.21 ± 0.13% with 92.91% confidence level.
Landfill leachate imposes a huge problem to the environment and human beings. This work focused on bioconversion of leachate to acetic and butyric acids by Clostridium butyricum NCIMB 7423. A continuous stirred tank reactor (CSTR) was applied and connected to fabricate membrane module. The leachate was collected from Pulau Burung Landfill Site (PBLS), Nibong Tebal, Penang. Prior to fermentation, leachate was treated to remove volatile fatty acid and adjusted to meet the minimum requirement of nutrients for anaerobic fermentation. Synthetic medium fermentation acts as a benchmark to the leachate fermentation. The outcomes indicated that the yield of acetic acid and butyric acid in synthetic medium fermentation was 0.70 g/L and 0.71 g/L, respectively. Meanwhile, leachate fermentation showed that the yield of acetic and butyric acid was 0.93 g/L and 1.86 g/L, respectively. High production of acetic and butyric acid showed that leachate fermentation is a green alternative to produce a cleaner product.