EXTRACTION AND CHARACTERIZATION OF NEEM SEED OIL. A RESEARCH PROJECT TOPIC ON BIOCHEMISTRY
Abstract
The extraction and characterization of oil from Neem seeds was studied. The results obtained showed that the moisture content of Neem seeds, is 41.0%, , which indicates that Neem leaves possesses the highest amount of oil. Furthermore, the results from the characterization of the oils showed that Neem leaf oil is denser than those obtained from Neem seeds and bark, and so is the best for soap making. The results also indicated that the oil extract from Neem bark is the most acidic.
Chapter one
INTRODUCTION
Background to study
Plant oils are oils derived from plant sources, as opposed to animal fats or petroleum. Oils derived from plants have been used for thousands of years. Plant oils have been a healthy alternative to animal derived oils since their discovery. Plant oils are composed of compounds called triglycerides; which may exist in a highly unsaturated form or less{Zipperer, 2002} . Saturated compounds are compounds “saturated” with hydrogen; all available places where hydrogen atoms could be bonded to carbon atoms are occupied. Unsaturated compounds have double bonds (C=C) between carbon atoms, reducing the number of places where hydrogen atoms can bond to carbon atoms. Saturated compounds have single bonds (C-C) between the carbon atoms, and the other bond is bound to hydrogen atoms.
The three fatty acids in the first set of equations are usually different, but many kinds of triglycerides are known.
There are broadly three types of triglycerides viz: Saturated, Monounsaturated and Polyunsaturated triglycerides{Richardson et al. 2000}. In saturated triglycerides, most of the fatty acids are saturated.
In monounsaturated triglycerides, most of the fatty acids are monounsaturated; one pair of hydrogen atoms in the middle of the molecule is missing.
A polyunsaturated triglyceride has most of its fatty acids polyunsaturated. Polyunsaturated fatty acids are two or more pairs of hydrogen atoms short of saturation; two examples are omega-3 and omega-6 fatty acids (American Heart Association., 2010). However, unsaturated triglycerides are the main constituents of plant oils.
There are broadly two classes of plant oils viz: Essential Oils and Fixed Oils.
Essential oils are volatile, and are usually derived from the non-seed parts of the plants. Most fixed oils are the so-called “fatty oils”, and a majority of the fatty oils are derived from the seeds – hence the term oilseeds, meaning oil-bearing seeds. Some of the fixed oils are derived from vegetables & nuts. Essential oils have been used for centuries. They have been used extensively in ancient Rome, Greece, Egypt & the Middle East – as perfumes, flavours, deodorants, antiseptics & pharmaceuticals..
Statement of problem
As a result of new processing technologies, they can today be used for more functions as well. Essential oils refer to the subtle, aromatic and volatile liquids extracted from the flowers, seeds, leaves, stems, bark and roots of herbs, bushes, shrubs and trees through distillation{(Mary Ndung’u, et al. 2004}.
