Idea of Rapid Preparation of Fatty Acid Methyl Ester Using In Situ Derivatization from Fresh Horse Mussel

The analysis of the fatty acid (FA) profile requires multiple preparation steps, which are lipid extraction followed by derivatization of the FA into a fatty acid methyl ester (FAME). The procedures are time-consuming, and generally require large volumes of sample sizes and solvents. This report proposes a technique for the preparation of FAME from fresh horse mussels without a step of lipid extraction. A rapid in situ derivatization using N,N-dimethylformamide dimethyl acetal (DMF-DMA) methylation followed by alkali-transesterification was examined. In this method, acylglycerols and free fatty acids (medium to long-chain FA) of the sample are targeted to convert into FAME. Direct alkali-transesterification of the fresh sample gave only 58.7% FAME with 12.4% triglyceride and 21.1% FFA. The alkali in situ method showed low conversion efficiency due to the initial sample containing high contents of moisture and FFA (75.11% of the fresh sample and 14.3% of total oil, respectively). The reaction was developed by using two steps in situ derivatization. A 50 mg sample was methylated with 1 mL of DMF-DMA (100 °C, 15 min), followed by transesterified with 10 mL of 1% (w/v) NaOH in methanol (60 °C, 3 min). The conversion into FAME was monitored using size-exclusion HPLC with evaporative light-scattering detection. The column was a 100 Å Phenogel with toluene and 0.25% acetic acid as a mobile phase. The FAME yield of 79.9% with 7.8% triglyceride and 8.5% FFA was obtained. The two steps in situ derivatization gave a promising result with the higher conversion with lower FFA. It is a simple and rapid (less than 20 min) method that requires a low volume of sample and solvent for FAME preparation. However, increasing the conversion efficiency as well as the variety of samples should be further studied.

Pyrolysis Process of Fatty Acid Methyl Ester (FAME) Conversion into Biodiesel

Biodiesel is a biomass fuel that can replace petroleum diesel fuel. One of the advantages of biodiesel fuel as renewable energy source that it is more environmentally friendly than fossil fuels because biodiesel significantly reduces greenhouse gas emissions compared to fossil fuels. FAME (fatty acid methyl ester) is a derivative product of CPO (crude palm oil) that has been treated both physically and chemically. The main advantage of FAME lies in the low content of impurities, especially sulphure and metal content. FAME comes from vegetable oil raw materials, which contain high enough fatty acids, around 61-62%, and nowadays, it is used as a mixture with petroleum diesel. The characteristics of biodiesel obtained from the conversion of FAME into biodiesel by pyrolysis at a temperature range of 160 – 200 oC indicate that the biodiesel produced is density 0.8475 kg/m3, viscosity 3.053 cSt, calculated cetane index (CCI) 48.5, flash point 59oC, moisture content 223 ppm, and sulphure content of 0.07% m/m. The results obtained are below the maximum limit of the specified biodiesel quality requirements.