Transesterification synthesis of high-yield biodiesel from black soldier fly larvae by using the combination of Lipase Eversa Transform 2.0 and Lipase SMG1

Weishuai Lian,Wanli Xu,Xuan Liu,Shi He,Weifei Wang,Suijian Qi

doi:10.1590/fst.103221

Abstract

The larvae of black soldier fly (BSFL) are rich in lipids, and in the current study, BSFL was used to produce biodiesel by enzymatic transesterification with methanol. Biodiesel obtained by free lipase-catalyzed transesterification is always with side-reactions. To address the limitation of free lipase, for the first time, Lipase SMG1 and Lipase Eversa Transform 2.0 were combined to use as catalysts at the same time. The effects of different reaction conditions on the yield of biodiesel were investigated, including the type of enzyme, reaction temperature, and molar ratio of BSFL to methanol. The molar ratio of BSFL to methanol 1:3, one-step addition of methanol at 25 °C were selected as optimal conditions. The fatty acid methyl ester content achieved to 98.45% after 8h reaction under the optimal conditions. Moreover, the main properties of the final biodiesel indicators met the EN14214 biodiesel standard.

Highlights

Considering the environmental threats associated with the excessive use of fossil fuels (Yin et al, 2020), it is crucial to explore alternative renewable energy sources
The fatty acid methyl ester (FAME) yield increased dramatically when using the combination of Lipase Eversa Transform 2.0 and Lipase SMG1/LipaseG50 as the catalysts
A yield of 98.45% was obtained in the presence of both Lipase Eversa Transform 2.0 and Lipase SMG1.Figure 2 illustrated that after the transesterification, the content of TAG (1.02%), DAG (0.26%), MAG (0.10%), and FFA (0.17%) occupied less than that of the raw materials, and there was a high yield of FAME (98.45%)

Summary

Introduction

Considering the environmental threats associated with the excessive use of fossil fuels (Yin et al, 2020), it is crucial to explore alternative renewable energy sources. The black soldier fly is not a pest and can survive in a variety of complex environments such as kitchen waste and poultry manure with a short growth cycle (Somroo et al, 2019) It can inactivate pathogens and convert a large amount of low-value organic waste to high-value biomass, which makes them quite popular in many areas like waste-reducing (Singh & Kumari, 2019). Many efforts had been done in the catalytic 2.4 Analysis of fatty acid composition by GC ability of Lipase SMG1, and it’s the first time Lipase SMG1 was used in the production of biodiesel to obtain lower content of fatty acid (FFA), DAG, and MAG in the final system. 2 Materials and methods biodiesel product were all tested according to the methods of the American Society for Testing and Materials (ASTM)

Materials

Preparation of biodiesel by enzyme-catalyzed transesterification

Analysis of the composition of the reaction mixtures by HPLC

The effect of enzyme type on the yield of biodiesel

The effect of the substrate molar ratio on the yield of biodiesel

Properties of biodiesel

Conclusions