SCREENING OF PROXIMATE CONSTITUENTS OF THE LEAF EXTRACTS OF SIMAROUBA GLAUCA WHICH INCLUDES MOISTURE, PROTEIN, CARBOHYDRATES, ASH FIBRE AND LIPID CONTENT OF SIMAROUBA GLAUCA

CHAPTER ONE

1.1 INTRODUCTION

Plants undergo photosynthesis and they constitute a primary resource of carbon, vitamins, minerals, protein, essential fatty acids, and utilizable energy for food production (Young and Pelett, 1994). Plants have played a significant role in maintaining the health and improving the quality of human life for thousands of years. (Mishra, 2010).  They provide a major source of food and nourishment for man and animal.

Nutrition is a science of food and its relationship to health. Nutrition refers to nourishment that sustains life. The study of nutrient requirements and the diet providing these requirements is also known as ‘nutrition’ (Chutani, 2008). Pike and Brown, 1984 defined it as “the science that interprets the relationship of food to the functioning of living organism. It includes the uptake of food, liberation of energy, elimination of wastes and all the processes of synthesis essential for maintenance, growth and reproduction (Chutani, 2008).  Apart from maintaining normal body functioning, nutrition is important in fighting infections and in the recuperation of an ill person. Nutrition interacts with infections in a synergistic manner, such that recurrent infections lead to a loss of body nitrogen and worsen nutritional status; theresulting malnutrition, in its turn, produces a greater susceptibility to infection (Kurpad, 2005). Aristotle (384-322 B.C.) was the first to suggest that the composition of foods in the normal diet might contribute to health.

In an 1897 literature on metabolic investigations, Atwater divided food composition into five classes; protein, fat carbohydrate, energy and water. However, today, proximate composition is the term usually used to describe six components of food namely; moisture, crude protein, crude ash,crude fibre, crude fat and carbohydrate (nitrogen free extract) which are all expressed in percentage (%) or gram per 100 grams (g/100g). The study of proximate analysis on foods was devised over a hundred years ago by two German scientists, Henneberg and Stohmann, and even though new techniques have been introduced, their system of proximate still forms the basis for the statutory declaration of the composition of foods. (Dublecz, 2011).

1.2 MOISTURE CONTENT

Water is essential for every living organism. In the human body, water content ranges from 50- 70% in different tissues. It is present in different fluid compartments of the human body- Intracellular (fluid inside the cells) and extra cellular. Plasma, interstitial fluid, cerebrospinal fluid, ocular fluid, lymph, peritoneal, pericardial, pleural and synovial fluids are part of the extra cellular fluid (Chutani, 2008).  However, the moisture content of a feed is seldom of interest nutritionally as water is usually taken on its own.

The active ingredients from the view of feed nutrition are present in the part of dry matter (solid matter); therefore the level of moisture content is an important factor in both economy and storage (Famic).  At high temperature and humidity  the risk of putrefaction is predicted due to the proliferation of molds, etc., or self-digestion by enzymes in the feed when moisture in the feed is not less than about 15 %.  As the assay for moisture in the feed measures loss on drying by heating at normal pressure as moisture, the result includes most of volatile substances other than H2O.  Therefore, it may be more appropriate to be referred to as volatile matter rather than moisture for accuracy.  Organic acids such as acetic acid and butyric acid in silage as well as ammonia and flavor components in feed materials are also vaporized and thus measured as moisture.  Because the content of these in most feed is extremely low, there has hardly been a need to consider their influence on the measured value. (Famic)

1.3 CARBOHYDRATES

Photosynthesis is a process used by plants and other organisms to convert light energy from the sun, into chemical energy that can be later released to fuel the organisms’ activities. The light energy harnessed from the sun drives the reduction of carbon from CO2 to produce O2 and fixed carbon in form of carbohydrate.

Early in the twentieth century, it was mistakenly thought that light absorbed by photosynthetic pigments directly reduced CO2 which then combined with water to form carbohydrate. In fact, photosynthesis in plants is a two stage process in which light energy is harnessed to oxidise H₂O:

2H₂O        →          O2 + 4 [H+][SO1]

The electrons thereby obtained subsequently reduce CO₂:

4 [H₂O] + CO₂ → (CH₂O) + H₂O[SO2]

The two stages of photosynthesis are traditionally referred to as the light reactions and the dark reactions:

1. In the light reactions, specialised pigment molecules capture light energy and are thereby oxidized. A series of electron- transfer reactions which culminate with the reduction of NADP⁺ to NADPH, generate ATP from ADP + Pi. The oxidised pigment molecules are reduced to H₂O, thereby generating O₂.
2. The dark reactions use NADPH and ATP to reduce CO₂ and incorporate it into the three-carbon precursors of carbohydrate.

SCREENING OF PROXIMATE CONSTITUENTS OF THE LEAF EXTRACTS OF SIMAROUBA GLAUCA WHICH INCLUDES MOISTURE, PROTEIN, CARBOHYDRATES, ASH FIBRE AND LIPID CONTENT OF SIMAROUBA GLAUCA