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 (Westhet 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
1
simultaneouslymitigatingmany
of the side effects that are often associated withsynthetic antimicrobials
(Harishchandraet
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 andyoung
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.
2
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; Yasunakaet 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; Madunaguet 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