CHAPTER
ONE
1.0 INTRODUCTION AND LITERATURE REVIEW
1.1 INTRODUCTION
Medicinal plants represent a rich source of antimicrobials and many other drugs. The potentialsof
higher plants as source for new drugs is still largely unexplored. Antibiotic resistance has become a
global concern (Westh et al., 2004). The clinical efficacy of many existing antibiotics is being
threatened by the emergence of multidrug-resistant pathogens (Bandow, 2003). Many
infectiousdiseases have been known to be treated with herbal remedies throughout the history of
mankind. Natural products, either as pure compounds or as standardized plant extracts, provide
unlimited opportunities for new drug leads because of the unmatched
availability ofchemical diversity.
There is a continuous and urgent need to discover new antimicrobial compounds
with diversechemical
structures and novel mechanisms of action for new and re-emerging infectious diseases (Rojas et al.,
1992). Therefore, researchers are increasingly turning their attention tolocal herbs, looking for new
leads todevelop better drugs against microbial infections (Benkeblia,
2004).
The increasingfailure of chemotherapeutics and antibiotic resistanceexhibited
by pathogenic microbial
infectious agents has led to the screening of several medicinal plants for their potential antimicrobial
activity (Kapila, 2005;Runyoro et al.,2006). The rising prevalence of antibiotics resistant pathogenic
microorganisms raises the demand for finding new alternative antimicrobial
agents. The drugs already
in use to treat infectious diseaseare of concern because drug safety remains an
enormous global issue.
Most of the synthetic drugscause side effects and also most of the
microbesdeveloped resistant against
the synthetic drugs (Chanda and Rakholiya 2011). To alleviate this problem,
antimicrobial compounds
frompotential plants should be explored. These drugs fromplants are less toxic;side effects are scanty
and alsocost effective. They are effective in the treatment ofinfectious diseases while
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simultaneouslymitigatingmany
of the side effects that are often associated withsynthetic antimicrobials
(Harishchandra et
al., 2012).
Published studies in medical journals
show that coconut in one form or another may provide a wide
range of health benefits. The coconut plant Cocos nucifera (family Arecaceae) is considered as an
important fruit crop in tropical countries. It is commonly available plant with wide variety of
applications in food, drinks, fibers,
building materials and various chemicals finding their way into a
huge range of modern day products. Being highly nutritious coconuts have also been studied for
medicinal qualities.
Modern medical science is now confirming the medicinal qualities of Cocos
nucifera which are used
for the treatment wide range of infections. Based on the knowledge of the
traditional herbs used for the
treatment for local application, coconut husk can be use as a topical antimicrobial. As preliminary
investigation of the use of coconut husk, the antimicrobial activity can be
evaluated.
1.2 AIM AND OBJECTIVES
The specific objectives are
to:
(a) Evaluate the phytochemical and antimicrobial activities of Methalonic extract of young Cocos
nucifera husk
on selected pathogenic microorganisms.
(b) Evaluate the antimicrobial activities and young Cocos nucifera water on selected pathogenic
microorganisms
1.3 JUSTIFICATION OF THE
RESEARCH
Cocos nucifera husk and
Cocos nucifera water
are traditionally used in the treatment of wide variety of
diseases, it has been used from time immemorial for the treatment of carcinogenic infections. This
study scientifically justifies the use of young Coconut husk and young Coconut
water in traditional folk
medicine and to compare their antimicrobial potency with the commercial
antibiotics.
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1.4LITERATURE REVIEW
1.4.1 MEDICINAL PLANTS AS ANTIMICROBIAL
AGENT
Medicinal plants have always been considered as a source for healthy life for people. Therapeutical
properties of medical plants are very useful in healing various diseases and the advantage of these
medicinal plants are natural (Kalemba and Kunicka , 2003).
In many parts of the world, medicinal plants
have been used for its antibacterial, antifungal and antiviral activities for
hundreds of years (Ali et
al.,
1998;Barbour et al., 2004;Yasunaka et al., 2005). Researchers are increasingly turning their attention
to natural products and looking for new leads to develop better drugs against
cancer, as well as viral and
microbial infections (Ibrahim, 1997; Towers et al ., 2001; Koshy et al ., 2009). Several synthetic
antibiotics are employed in the treatment of infections and communicable diseases. The harmful
microorganisms can be controlled with drugs and this has resulted in the emergence of multiple drug
resistant bacteria and it has created alarming clinical situations in the
treatment of infections.
In general, bacteria have the genetic ability to transmit and acquire
resistance to synthetic drugs which
are utilized as therapeutic agents (Murray, 1992; Madunagu et al ., 2001; Koshy et al ., 2009;
Senthilkumar and Reetha , 2009) Therefore, actions must be taken to reduce this problem, such as to
minimize the use of antibiotics, develop research of resistance among
microorganism and to continue
studies to develop new antibiotic and immune modulating compounds with diverse
chemical structures
and novel mechanisms of action, either synthetic or natural to control pathogenic microorganisms
because there has also been an alarming increase in the incidence of new and re-emerging infectious
diseases (Ikenebomeh and Metitiri, 1988;Rojas et al. ,
2003)
Antimicrobial studies have shown that Gram-negative bacteria show a higher
resistance to plant extracts
than Gram-positive bacteria. This may be due to the variation in the cell wall structures of Gram-
positive and Gram-negative bacteria. More specifically, Gram-negative bacteria
has an outer membrane
that is composed of high density lipopolysaccharides that serves as a barrier to many environmental