ABSTRACT
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This research investigated the phytochemical and anti-inflammatory
properties of methanol extract of Crateva adansonii stem bark. Although
several edible and non-edible plants parts are used in inflammatory
treatment, many record has been found of the use of Crateva adansonii
stem bark. For this research, fresh stem bark of Crateva adansonii were
collected from Asata village in Enugu State. The cuttings were authenticated
at the Bioresource development centre. They were then dried at room
temperature for one month in an open lab space, grounded into powder and
weighed on a beam balance as 460.6g. The powder was soaked for twentyfour
to fourty-eight hours in methanol to get a methanol extract and then
concentrated into paste at a set temperature range of 30-550C in a water
bath. A population of twenty adult wistar Albino rats was used for antiinflammatory
test. The rats were divided into five (5) groups of four (4)
albino rats each. They were administered 3% tween-80 mixed with
dichloromethane extract of Crateva adansonii and the control was
administered with 0.5ml of 3% tween-80. Acute inflammation was induced
an hour after test substances were administered by injecting egg albumin in
the subplanter region of the right hind paw and edema assessed by mercury
displacement for a period of 0-180 minutes. Anti-inflammatory effect was
significant within 30 minutes of induced edema with inhibition occurring in
three phases of 0-30, 30-60, 60-90. 90-120 to 180 minutes. Inhibition was
highest at the third phase. Crateva adansonii barks showed antiinflammatory
effect by inhibiting “prostaglandin” synthesis an inflammatory
mediator.
CHAPTER ONE
1.0 INTRODUCTION
Inflation is a Latin word (inflammare) which is translated means to set on
fire. It is a complex biological response of vascular tissue to harmful stimuli
such as pathogens, damaged cells irritant. Inflammation is the reaction of
vascularized tissue to local injury caused by certain stimuli like infections,
chemicals and biochemical agents, thermal or other physical trauma,
antigen-antibody interaction etc (Carol, 1994). Without inflammatory
response, wounds will not heal and minor infections would be over weening.
Though inflammation aims at limiting damage and restoring function, some
enzymes and toxic products within phagocytic cells are released to the
extend of damaging the tissue. The advent of anti-inflammatory agents has
made inflammation which as been a threat to human life due to its complex,
multicontent, to loose its power. These anti-inflammatory agents or drugs
help reduce, pain by inhibiting inflammation as opposed to opioids, which
affects the central nervous system. It also prevent repairs, prevent and stop
the consequences of inflammation by acting on the body responses without
directly antagonizing the causative agent (Stedman, 2000). These antiinflammatory
process involves the process of balancing pro-inflammatory
acute-phase reactants (Russell et al. 2000), altering biochemical pathway
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forming prostaglandins by inhibiting cyclooxygenase enzyme from
catalyzing the reaction, as a result, suppress, compensate and correct the
mechanical and structural abnormalities by assistive device. (Masumoto et
al.2009).
The inflammatory reaction is phylogenetically and ontogenetically the oldest
defense mechanism. The cells of immune system are widely distributed
throughout the body, but if an infection or tissue damage occurs. It is
necessary to concentrate them and their products at the site of damage.
Three major events occurring during this response:
1. An increased blood supply to the damaged tissue . It is performed by
vasodilation. The inflamed tissue look like containing greater number
of vessels.
2. Increased capillary permeability caused by retraction of the
endothelial cells. This permits larger molecules than usual to escape
from the capillaries, and thus allows the soluble mediators of
immunity to reach the site of inflammation.
3. Leukocytes migrates out of the capillaries into the surrounding tissues.
In the earliest stages of inflammation, neutrophils are particularly
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prevalent, but later monocytes and lymphocytes migrate towards the
site of infection (Ashcroft et al.1999).
For the possibility of surrounding tissue damage, inflammatory responses
must be well ordered and controlled. The body must be able to act quickly in
some situations, for example to reduce or stop the lost of blood, whereas
tissue repair can begin later. Therefore a wide variety of interconnected
cellular and humoral (soluble) mechanisms are activated when tissue
damage and infections occur. On the other hand, if injury is negligible, the
body must have mechanisms which are able to stop tissue damage when the
agent is removed. The development of inflammatory reactions is controlled
by cytokines, products of plasma enzymes (complement, the coagulation
clotting, kinin and fibrolytic pathways), by lipid mediators (prostaglandin
and leukotrienes) released from different cells/ and by vasoactive mediators
from the mast cells, basophils and platelets. These anti-inflammatory
reactions differ. Fast-acting mediators such as vasoactive amines and the
product of the kininsystem, modulate the immediate response. Later, newly
synthesized mediators such as leukotrienes are involved in the accumulation
and activation of other cells. However, in inflammatory reactions initiated
by the immune system, the ultimate control is exerted by the antigen itself in
the same ways it controls the immune response itself. For this reason, the
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cellular accumulation at the site of chronic infection or auto-immune
reactions where antigen cannot ultimately be eradicated, is quiet different
from the sites were antigenic stimulus can be rapidly cleared.
The nervous system can also participate in the control of inflammation
especially axon reflexes, but inflammation may be realized in non-nervous
tissues as well.
Inflammation may become chronic in certain settings where the acute
process characterized by neutrophil infiltration and swelling gives way to
predominance of mononuclear phagocytes and lymphocytes.This probably
occurs to some degree with the normal healing process but becomes
exaggerated and chronic when there’s ineffective elimination of foreign
materials as in certain infections (e.g tuberculosis) or following introduction
of foreign bodies (example asbestos) or deposition of crystals (example urate
crystals). Chronic inflammation is often associated with fussion of
mononuclear cells to form multinucleated gigantic cells, which eventually
become granuloma. Chronic inflammation is seen under of delayed
hypersensitivity (Nathan, 2002).
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1.2 CRATEVA ADANSONII AS A PLANT.
The flowering tree crateva religiosa (syn crateva adansonii) is called the
sacred garlic pear and temple plant, and many other names in a variety of
dialets, including Balai, lamok, abiyuch, barna, varuna and bidasi. The tree
is sometimes called the spider tree because the showy flower bear long,
spidery stamens. It is native to Japan, Australia, much of South East Asia
and several South east Asia and several South pacific islands. It is grown
elsewhere for fruit especially in part of African continent.
The crateva adansonii plant is a moderate sized, spreading unarmed,
deciduous tree growing to a height of 15 meters. Bark is grey, the wood
yellowish-white turning light brown when old. Leaves are clustered at the
end of the branchlets with a common petiole 5-10 centimeter long, at the
summit of which are three leaflets. Leaflets are ovate-lanceolate or ovate
7.5-12 centimeter long, 4-6 centimeter wide. Pointed at the base rather
slender pointer at the tip. Flower occur in terminal corymbs, about 5
centimeters in diameter, greenish yellow, and at length purplish.
Petals are ovate or oblong with the claw haft as long as the limb. Fruit is
ovoid or rounded, 3-5 centimeter in diameters, with a hard and rough rind.