Lipid Identification and Extraction Techniques - Biotechnological Applications of Microalgae - page 89

7 Lipid Identification and

Extraction Techniques

Desikan Ramesh
Department of Farm Machinery
Agricultural Engineering College and Research Institute
Tamil Nadu Agricultural University
Coimbatore, Tamil Nadu, India

CONTENTS
7.1 Lipid Quantification ........................................................................................ 89
7.2 Lipid Profiles .................................................................................................. 90
7.2.1 Identification of Algae Lipid Profiles ................................................. 90
7.2.2 Suitability of Algae Lipid for Biodiesel Production ........................... 90
7.3 Oil Extraction ................................................................................................. 92
7.3.1 Mechanical Extraction ........................................................................ 92
7.3.1.1 Oil Expeller .......................................................................... 93
7.3.2 Chemical Extraction ........................................................................... 93
7.3.2.1 Solvent Extraction ................................................................ 93
7.3.2.2 Supercritical Fluid Extraction (SFE) ................................... 94
7.4 Conclusion ...................................................................................................... 95
References ................................................................................................................ 96

7.1 LIPID QUANTIFICATION
Due to their high oil content, microalgae have attracted substantial research atten-
tion for biodiesel production and furthermore, algae have the capability to replace
conventional biodiesel feedstocks. Algal strains collected from diverse aquatic
environments require the evaluation of various important parameters such as oil
content, lipid composition, growth rate, and metabolic efficiency under different
conditions. One can decide whether the selected algal strain is suitable/unsuitable
for biodiesel production based on the preliminary lipid analysis (both lipid yield and
lipid composition).
Microalgal strains have the potential to produce up to 50% lipid by dry cell weight,
depending on the species and specific growth conditions (Chisti, 2007). The neutral
lipids present in microalgae are primarily in the form of triacylglycerols (TAGs).
TAGs can be converted to fatty acid methyl esters (FAMEs) via transesterification.
Recovery of the accumulated algae lipids from algae paste is generally carried out
after rupturing the cells to free the lipids. Different cell disruption techniques are

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