Comparison of ex-situ and in-situ transesterification for the production of microbial biodiesel

• Main Authors: Hazmi, Alia Tasnim, Ahmad, Farah, Athoillah, Ahdyat Zain, Jameel, Ahmad Tariq
• Format: Article
• Language: English; English
• Published: Diponegoro University 2021
• Subjects: TP155 Chemical engineering; TP248.13 Biotechnology; TP315 Fuel; TP500 Fermentation industries. Beverages. Alcohol; TP670 Oils, fats, waxes
• Online Access: http://irep.iium.edu.my/91663/1/91663_Comparison%20of%20ex-situ%20and%20in-situ.pdf; http://irep.iium.edu.my/91663/2/91663_Comparison%20of%20ex-situ%20and%20in-situ_SCOPUS.pdf; http://irep.iium.edu.my/91663/; https://ejournal2.undip.ac.id/index.php/bcrec/article/view/11044

Microbial biodiesel is converted from microbial lipids via transesterification process. Most microbial biodiesel re-search is focusing on the use of microalgal lipids as feedstock. Apart from the microalgae, lipids can also be ex-tracted from other oleaginous microorganisms like fungi and yeast. However, there are gaps in the studies of lipid production from filamentous fungi, especially in-situ transesterification process. The aim of this project is to com-pare in-situ with the ex-situ transesterification of fungal biomass from Aspergillus oryzae. In ex-situ transesterifi-cation, two methods of lipid extraction, Soxhlet extraction and Bligh and Dyer extraction, were performed. For in-situ transesterification, two methods using different catalysts were investigated. Base-catalyzed in-situ trans-esterification of fungal biomass resulted on the highest Fatty Acid Methyl Esters (FAME) yield. The base-catalyzed in-situ transesterification was further optimized via Central Composite Design (CCD) of Response Sur-face Methodology (RSM). The parameters investigated were the catalyst loading, methanol to biomass ratio and reaction time. The optimization showed that the highest FAME yield was at 25.1% (w/w) with 10 minutes reaction time, 5% catalyst and 360:1 of the ratio of the methanol to biomass. Based on Analysis of Variance (ANOVA), the model was found to be significant according to the value of “Prob >F” of 0.0028