ABSTRACT

Azadirachta indica is a tree in the mahogamy family maliaceae growing in tropical and sub-tropical regions. Alkaloid on the other hand are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. In the extraction of alkaloid from Azadirachta indica leaves, 200g of dry powdered Azadirachta indica leave was weigh and defatted with 200mls of n-hexane for 24 hours in a 500ml conical flask and decanted away. Solution of acetic acid and ethanol was added to the residue and was shake and allow to stand for 4 hours, filtered and the filtrate was evaporate to ¼ of its original volume. 80ml of Ammonium hydroxide was added drop wise to precipitate and  was filtered off with filter paper. The alkaloid in the filter paper was place in 3 different places on a thin layer chromatographic plate and was place inside a chromatography tank in the solution of chloroform and methanol for 1 hour, dragendroff’s reagent was spread on the plate to detect only the alkaloid in the plate. CHAPTER ONE

1.0  INTRODUCTION

1.1BACKGROUND

Azadirachta indica is a native tree of India. It is a tree in the mahogany family maliaceae growing in tropical and sub-tropical regions, its fruits and seed are the sources of Azaodirachta indica oil (zillur etal, 2006).

Azaodirachta indica is a fast growing tree that can reach a height of 15 – 20 metres (49 – 66ft) rarely to 35 – 40 metres (115 – 130ft) it is evergreen but in severe drought it may shed most of nearly all of its leaves. TheAzaodirachta indica tree is noted for its drought resistance, normally it thrive in areas with sub-arid to sub-humid conditions with an annual rainfall 400 – 1,200 millimeters (16 – 47). It can grow in regions with annual rainfall below 400mm, but in such cases it depends largely on ground water levels.Azaodirachta indica can grow in many different types of soil but it thrives best on well drained deep and sandy soils. it can tolerate high to very high temperature and does not tolerate temperature below 40C (390F) (Zillui et al, 2004).

Alkaloids are group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Also some synthetic compounds of similar structure are attributed to alkaloids in addition to carbon, hydrogen, sulphur and more rarely other elements such as chlorine, bromine and phosphorus.

Alkaloids are produced by a large variety of organisms including bacteria, fungi, plant and animals and are part of the group of natural products (also called secondary metabolites). Many alkaloids can be purified from crude extract by acid-base extraction. Many alkaloids are toxic to other organisms. They often have pharmacological effects and are used as medications as recreational drugs, or in enthegogenic rituals. Examples are the local anesthetic and stimulant cocaine (Kausik, 2006).

The boundary between alkaloids and other nitrogen-containing natural compound is not clear cut. Compounds like amino acid peptides, proteins, nucleotides, nucleic acid, amines and antibiotics are usually not called alkaloids. Naturally compounds containing nitrogen in the exocyclic position (Mescaline serotonin, dopamine) are usually attributed to amines rather than alkaloids (Gangli, 2002).

The name alkaloid was introduced in 1819 by the German chemist Carl F.W Meissner. there is no unique method of naming alkaloids, Many individual names are formed by additing the suffix “ine” to the species or generic alkaloids. For example, atropine is isolated from the plant Atrop belladonia, strychinine is obtained from the seed of strychnione tree. If several alkaloids are extracted from one plant then their names often contain suffixes “idine”, “anine”, “aline”, etc (Lewis, 2005).

There are three alkaloids extracted from neem leaf Viz Gudunine, nimbin and nimbidin. Because of the structure diversity of alkaloids, there is no single method of their extraction from natural raw materials. Most alkaloids are  soluble in organic solvents but not in water, and the opposite tendency of their salts. most plants contain several alkaloids. Their mixture is extracted first and then individual alkaloids are separated. Plants are thoroughly ground before extraction. Most alkaloids are present in the raw plants in the form of salts of organic acids. The extracted alkaloids may remain salts or change into bases. The nimbin contains acetoxy, a lactone, an estare, a methoxy and an aldehyde group. Nimbidin contains sulphur. Gudunin contains meliacins. Guducin shown potent anti inflammatory activity in experimental animals while nimbin and nimbidin have been found to have anti viral activity. They affect potato virus x, vaccinal virus and fowl POX virus (Leland, 2006).

1.2AIMS OF THE STUDY

The aim of this research project is to determine the alkaloids found inAzaodirachta indica plant.

1.3STATEMENT OF THE PROBLEM

The major problem associated with alkaloid is that  many alkaloid are toxic to human, adequate measures are taken to know the toxicity and the amount of toxic substance present in the alkaloid. Alkaloid potends a tremendous potential as medicinal drugs and the study of their properties and application is an endless quest in providing remedies to human and animal ailment

1.4SIGNIFICANCE OF THE STUDY

The importance of this study is to determine and isolate the alkaloids present in Azadirachta indica leave.

1.5SCOPE OF THE STUDY

The scope of this study is limited to the determination of alkaloid fromAzadirachta indica leaves.