Soybean
is one of the most economical and nutritious foods which can combat the
diseases stemming from malnutrition and the nutraceutical ingredients present
in it and can reduce the risk of major chronic diseases like cancer,
atherosclerosis, osteoporosis and diabetes (Vineet, 2007). Soybean is an
excellent source of quality protein and compares well with animal protein in
essential amino acids pattern with the exception of sulphur containing amino
acids. Soybean is the concentrated source of vegetable proteins. It contains
about 40%protein and 20% oil.

Proteins
are abundantly rich in lysine which is a limiting amino acid in most of the
cereals. Soy fat being highly unsaturated has been found to be nutritionally
desirable. Therefore, it can easily supplement the diet of poor Indians
(Chauhan, 2005). It has high proportion of unsaturated fatty acids, such as
linoleic and linolenic acids, it is considered as highly healthful oil. The
ratio of polyunsaturated fatty acid to saturated fatty acid is 82:18, which is
highly conducive to lower the blood cholesterol. Soy food contains most of the
desirable characteristics therefore; it may be treated as consummate functional
food.

Soybean
also contains many minor substances, which are biologically active non
nutritive components known as “phytochemicals”, “isoflavones” or “phytoestrogen” also known as
coumesterol or “plant estrogen” very
similar to that of female sex hormone estrogen) with very weak activity of
estrogen, which offers unique health benefits.

Soybean
is a good source of niacin, riboflavin, iron, potassium, calcium, magnesium,
and phosphorous with several fat and water soluble vitamin Bcomplex (Tripathi,
2005). Soybeans are often called the “miracle crop.” They are the world’s
foremost provider of vegetable protein and oil. The bushy, green soybean plant
is a legume related to peas, groundnuts (peanuts) and alfalfa.

Soybeans
are included in the category of oilseed, which is a generic reference to crops
with seeds that can produce edible and/or non-edible oil in economic
quantities. The most versatile of the world’s major crops, soybeans can be
grown in a wider variety of soil and climatic conditions than any other major
world crop. Consequently, soybeans are the most widely grown oilseed in the
world. In the last 20 years, scientists have learned how to extract a much
wider variety of byproducts from soybeans that are proving beneficial in animal
feed, human food and industrial applications.

Rats have a long history in medical research.
They were the first mammalian species specifically domesticated to be used in
the laboratory. They are thought to have originated in some parts of Asia; Rattus rattus was
well established in Europe by 1100 A.D., with Rattus norvegicus commonly found in Europe in the 1700s. By the 1800s, these animals
were used for neuro-anatomy studies in the United States and in Europe. It was
in the late 1800s and early 1900s that individual stocks and strains had their
beginnings (Animals in research, 2013; Sengupta, 2013).

The success of the rat in research today has
been linked to the Wistar Institute in the United States of America, when in
1906, the institute developed the Wistar albino strain (Rattus norvegicus) (The Wistar Institute: History, 2007).
Currently, there are 117 albino strains of the laboratory rat, all of which can
be traced genetically back to the one rat, likely to have arisen as a mutation from
a hooded (piebald) rat strain (Animals in research, 2013).

1.2   STATEMENT OF THE PROBLEM