International Journal of Pharmacy and Pharmaceutical Sciences, Vol. 1, Issue 1, July-Sep. 2009
Review Article
PLANTS IN TRADITIONAL MEDICINAL SYSTEM - FUTURE SOURCE OF NEW DRUGS
SOUMYA PRAKASH ROUT 1 *, K. A. CHOUDARY2, D. M. KAR3, LOPAMUDRA DAS4,
AVIJEET JAIN5
*Soumya Prakash Rout, 13-1-160/4/9, Plot No- 89, Snehapuri Colony, Motinagar, Hyderabad- 500 018, A. P., India
Cont. No- +91-9912838639, E-mail - [email protected]
1
Dept. of Clinical Operations, AdPharma India Private Limited, Hyderabad, India-500033
2
Dept. of Pharmacology, Roland Institute of Pharmaceutical Sciences, Berhampur, Orissa, India
3
Dept. of Pharmacology, Dadhichi College of Pharmaceutical Sciences, Phulnakhara, Cuttack, Orissa, India
4
Clinical Research Associate, GVK Bio, Hyderabad, India-500018
5
Natural Product Research Laboratory, Dept of Pharmaceutical Sciences, Dr H S Gour Vishwavidyalaya, Sagar, MP, India
ABSTRACT
The approach to new drugs through natural products has proved to be the single most
successful strategy for the discovery of new drugs, but in recent years its use has been
deemphasized by many pharmaceutical companies in favor of approaches based on
combinatorial chemistry and genomics, among others. Again with rapid industrialization
of the planet and the loss of ethnic culture and customs, some of the information on
ethnomedicine will no doubt disappear. An abundance of ethnomedical information on
plant uses can be found in scientific literature but has not yet been compiled into a usable
form. Collection of ethnomedical information especially in the developing countries
remains primarily an academic endeavour of little interest to most industrial groups. This
article reviews some of the past successes of the natural products approach and also
explores some of the reasons why it has fallen out of favor among major pharmaceutical
companies and the challenges in drug discovery from Natural Products especially Higher
Plants. In this review we consider the past, present, and future value of employing
information from plants used in traditional medical practices (ethnomedicine) for the
discovery of new bioactive compounds.
Keyword: Ethnomedicine, HTS, Bioprospecting, Prefractionation, Combinational chemistry
INTRODUCTION
western world documentation of use of
Ayurveda is the most ancient health care
Natural
system and is practiced widely in India,
purposes can be found as far back as 78
Srilanka and other countries1. Atharvveda
A.D., when Dioscorides wrote “De
(around 1200 BC), Charak Samhita and
Materia Medica”, describing thousands
Sushrut Samhita (100 - 500 BC) are the
of medicinal
main
detailed
included descriptions of many medicinal
descriptions of over 700 herbs 2. In the
plants that remain important in modern
classics
that
given
substances
plants3.
for
medicinal
This
treatise
1
medicine, not because they continue to
sector is focused on development of new
be used as crude drug preparations, but
innovative/indigenous plant based drugs
because they serve as the source of
through investigation of leads from the
important pure chemicals that have
traditional system of medicine5. The
become mainstays of modern therapy.
World Heath Organization has also
The term “materia medica” which
recognized the importance of traditional
means “Medical Materials”3 is no longer
medicine and has created strategies,
utilized routinely in Western medicine,
guidelines and standards for botanical
the fact remains that the physicians of
medicines.
today continue to use many substances
technologies need to be applied to the
and products derived from natural sources,
cultivation and processing of medicinal
usually for the same therapeutic benefit as
plants and the manufacture of herbal
the crude drug. These single chemical
medicines 6.
entities, i.e., drugs, form the basis for
Over the past decade, there has been a
much of our ability to control disease.
resurgence
In recent times, there have been
investigation of natural materials as a
increased waves of interest in the field
source of potential drug substance. This
of
Products
review is not intended to be an
Chemistry. This level of interest can be
exhaustive review of natural product-
attributed to several factors, including
derived pharmaceuticals, but rather is
unmet therapeutic needs, the remarkable
aimed at highlighting the invaluable role
diversity of both chemical structure and
that natural products have played, and
biological
continue to play, in the drug discovery
Research
in
Natural
activities
of
naturally
Proven
of
agro-industrial
interest
in
occurring secondary metabolites, the
process and its future perspectives.
utility
Background and issues
of
novel
bioactive
natural
the
products as biochemical probes, the
Natural
development of novel and sensitive
important role throughout the world in
techniques to detect biologically active
treating and preventing human diseases.
natural products, improved techniques to
Natural product medicines have come
isolate,
from various source materials including
purify,
and
structurally
products
have
played
an
characterize these active constituents,
terrestrial
and advances in solving the demand for
microorganisms, marine organisms, and
4
plants,
terrestrial
7
supply of complex natural products .
terrestrial vertebrates and invertebrates
The R & D thrust in the pharmaceutical
and its importance in modern medicine
2
has been discussed in different reviews
drugs worldwide reveals the utility of
and reports7-12.
natural products as sources of novel
The value of natural products in this
structures, but not necessarily the final
regard can be assessed from: (i) the rate
drug entity, is still alive and well14.
of introduction of new chemical entities
The development of high throughput
of wide structural diversity, including
screens based on molecular targets had
serving as templates for semisynthetic
led to a demand for the generation of
and total synthetic modification, (ii) the
large libraries of compounds to satisfy
number of diseases treated or prevented
the enormous capacities of these screens
by these substances, and (iii) their
and
frequency of use in the treatment of
combinatorial libraries has continued,
disease.
with the emphasis now being on small,
The large proportion of natural products
focused (100 to ~ 3000) collections that
in drug discovery has stemmed from the
contain much of the “structural aspects”
diverse structures and the intricate
of natural products8. Various names
carbon skeletons of natural products.
have been
Since
from
including “Diversity Oriented Syntheses”,
natural sources have been elaborated
preferably can be termed as “more
within living systems, they are often
natural product-like”, in terms of their
perceived as showing more “drug-
combinations
likeness and biological friendliness than
significant numbers of chiral centers
totally synthetic molecules,”9 making
within a single molecule15, or even
them
drug
“natural product mimics” if they happen
development11,13. Analysis of the sources
to be direct competitive inhibitors of the
of new and approved drugs during the
natural substrate. It should also be
period 1981 to 2002 reveals that natural
pointed out that Lipinski’s fifth rule
products play a highly significant role in
effectively states that the first four rules
the drug discovery and development
do not apply to natural products or to
process
secondary
good
12
metabolites
candidates
for
the
shift
away
given to
of
from
large
this process,
heteroatoms
and
. Review of all approved
any molecule that is recognized by an
agents during the time frame of more
active transport system when considering
than 25 years from 01/1981 to 06/2006
“druggable chemical entities” 14.
for all diseases worldwide and from
Although combinatorial chemistry in
1950 (earliest so far identified) to
one or more of its manifestations has
06/2006 for all approved antitumor
been used as a discovery source for
3
approximately
70%
of
the
period
countries are turning to the use of
01/1981 to 06/2006, only one new
traditional
chemical entity (NCE) reported in the
involve the use of herbal drugs and
public domain as resulting from this
remedies18 and according to the World
method of chemical discovery and
Health Organization (WHO), almost
approved for drug use anywhere. This is
65% of the world’s population has
the antitumor compound known as
incorporated the value of plants as a
sorafenib from Bayer, approved by the
methodology of medicinal agents into
FDA in 200514. Proudfoot also reported
their primary modality of health care19.
that 8 out of 29 small molecule drugs
It is often noted that 25% of all drugs
launched in 2000 were derived from
prescribed today come from plants20, 21.
Natural Products or hormones and
This estimate suggests that plant-derived
concluded that HTS did not have a
drugs make up a significant segment of
significant impact on the derivation of
natural product– based pharmaceuticals.
these drugs 16. Despite competition from
Out of many families of secondary
other drug discovery methods, Natural
metabolites, or compounds on which the
Products are still providing their fair
growth of a plant is not dependent,
share of new clinical candidates and
nitrogen-containing
drugs and there is rapidly evolving
contributed the largest number of drugs
recognition that a significant number of
to the modern pharmacopoeia, ranging
natural product drugs/leads are actually
in
produced by microbes and/or microbial
(atropine) to analgesics (opium alkaloids)
interactions with the “host from where it
and from antiparasitics (quinine) to
was isolated”, and therefore this area of
anticholinesterases
natural product research should be
antineoplastics (vinblastine/vincristine)
expanded significantly 14.
22
Importance of plants as a source of
in
new drugs
terpenoids (including steroids) have
The
development
of
effects
medicinal
from
systems
alkaloids
that
have
anticholinergics
(galantamine)
to
. Although not as plentiful as alkaloids
the
modern
pharmacopoeia,
traditional
made an equally important contribution
medicinal systems incorporating plants
to human health. They range from
as means of therapy can be traced back
Na+/K+ pump-inhibiting cardiac glycosides
to the Middle Paleolithic age some
from Digitalis spp.23, to antineoplastic
60,000 years ago as found from fossil
paclitaxel24 to antimalarial artemisinin25,
studies17. In recent times, developed
to anti-inflammatory triptolide26, 27. It is
4
important to note that, the activity of
based,
some natural products has yet to be
morphine,
certified by extensive testing or clinical
khellin, and khellin; c) to use agents as
trials;
pharmacologic tools, e.g., lysergic acid
as
multicomponent
botanical
(MCBTs).
This
therapeutics
respectively,
taxol,
diethylamide,
on
galegine,
podophyllotoxin,
mescaline,
yohimbine;
overrepresentation of natural product–
and d) to use the whole plant or part of it
derived drugs begs the question of
as a herbal remedy, e.g., cranberry,
whether plant secondary metabolites and
echinacea,
related synthetic compounds perform
biloba, St. John’s wort, saw palmetto.
better
randomly
The number of higher plant species
synthesized compounds. Despite the
(angiosperms and gymnosperms) on this
increasing use of medicinal plants and
planet is estimated at 250,00028, with a
their importance in drug discovery, their
lower level at 215,00029, 30 and an upper
future, seemingly, is being threatened by
level as high as 500,00031,
complacency
their
about 6% have been screened for
conservation. Reserves of herbs and
biologic activity, and a reported 15%
stocks of medicinal plants in developing
have been evaluated phytochemically33.
countries are diminishing and in danger
With high throughput screening methods
of extinction as a result of growing
becoming more advanced and available,
industrialization.
these numbers will change, but the
The goals of using plants as sources of
primary discriminator in evaluating one
therapeutic agents are,
plant species versus another is the matter
a) to isolate bioactive compounds for
of approach to finding leads. There are
direct use as drugs, e.g., digoxin,
some broad starting points to selecting
digitoxin, morphine, reserpine, taxol,
and obtaining plant material of potential
vinblastine, vincristine; b) to produce
therapeutic interest. However, the goals
bioactive compounds of novel or known
of such an endeavor are straightforward.
structures
for
Plants have an advantage in this area
semisynthesis to produce patentable
based on their long-term use by humans
entities of higher activity and/or lower
(often hundreds or thousands of years).
toxicity,
One
as
drugs
concerning
as
e.g.,
oxycodon
than
lead
compounds
metformin,
other
might
expect
garlic,
any
32
ginkgo
and only
bioactive
narcotic
compounds obtained from such plants to
teniposide,
have low human toxicity. Obviously,
verapamil, and amiodarone, which are
some of these plants may be toxic within
analgesics),
(and
nabilone,
feverfew,
taxotere,
5
nordihydroguaiaretic
reporting system to document these
which, besides being active orally in
effects. It is unlikely, however, that
db/db diabetic mice, also lowered
acute toxic effects following the use of a
cholesterol levels.
plant in these cultures would not be
Some examples of drugs from plants
noticed, and the plant would then be
that served as models for the next
used cautiously or not at all. Chronic
generation of drugs are exemplified as
toxic effects would be less likely to
follows: Khellin [from Ammi visnaga
signal that the plant should not be used.
(L.) Lamk] was used as a bronchodilator
In
of
in the United States until it was shown
secondary plant metabolites those results
to produce nausea and vomiting after
from plant evolution may be equal or
prolonged use. In 1955 a group of
superior to that found in synthetic
chemists in England set about to
combinatorial chemical libraries.
synthesize khellin analogs as potential
Approaches of drug discovery from
bronchodilators with fewer side effects.
higher plants
This eventually led to the discovery of
Shaman Pharmaceuticals in South San
chromolyn (used as sodium chromoglycate),
Francisco, California is supposed to be
which stabilized cell membranes in the
the first company in United States to
lungs to prevent the allergeninduced
investigate plants through ethnomedical
release of the substance ultimately
addition,
34
approach
chemical
diversity
acid
(ndga)43
a given endemic culture that has no
and SP-303, an oligomeric
causing bronchoconstriction in allergic
proanthocyanidin35 found in the process,
asthma patients44. Further studies led to
was shown to be clinically efficacious
the synthesis of amiodarone, an useful
and is currently marketed as a dietary
antiarrythmia agent44. Papaverine, useful
supplement for diarrhea. In addition, a
as a smooth muscle relaxant, provided
major
the basic structure for verapamil,
effort
was
directed
toward
discovery of novel antidiabetic agents,
drug
which resulted in the discovery of
Galegine was isolated as an active
several
compounds:
antihyperglycemic agent from the plant
cryptolepine36-38, maprouneacin39, 3 ,30-
Galega officinalis L. used ethnomedically
dihydroxylupen-20(29)-en-2-one40,
for the treatment of diabetes. Galegine
harunganin,
patented
vismin41,
and
used
to
treat
a
44
hypertension .
quinines
provided the template for the synthesis
SP18904 and SP18905 . The most
of metformin and opened up interest in
42
interesting
discovery
was
6
the synthesis of other biguanidine-type
A number of reviews relating to
antidiabetic drugs44.
approaches for selecting plants
It is always difficult to assess the value
candidates for drug discovery programs
of any approach to the use of higher
have been published46,47-60 and these
plants to develop new drugs. Artuso has
approaches can be briefly outlined as
outlined the entire process: formulating
follows,
an
•
appropriate
biologic
strategy,
extracts,
obtaining
screening
those
extracts, isolating active compounds,
conducting
preclinical
tests
•
followed
•
Random selection followed by one
Follow-up
of
biologic
activity
reports
•
New Drug Application, and beginning
Follow-up of ethnomedical (traditional
medicine) uses of plants
commercial production. According to
•
his estimation the entire process would
Challenges and opportunities
45
by
or more biologic assays
Investigational New Drug Application,
performing clinical trials, submitting a
selection
chemical screening
and
chemical modification, submitting an
Random
as
Use of databases
take 10–20 years or more . As it is
In spite of the success of different drug
improbable that one could collect all the
discovery programmes from plants in
250,000 higher plant species to screen
the past 2–3 decades, future endeavours
for one or more biologic activities, and
face many challenges. Natural products
because the number of bioassays that
scientists and pharmaceutical industries
one could screen these species for is
will need to continuously improve the
unlimited, the species most likely to
quality and quantity of compounds that
produce
be
enter the drug development phase to
selected judiciously. In addition, the
keep pace with other drug discovery
biologic targets must represent the
efforts. The approach of herbal drug
activities that correlate best with the
development is associated with several
rationale for plant selection. It would
problems.
appear that selection of plants based on
•
useful
activity
should
The advent of routine HTS has
long-term human use (ethnomedical) in
been one of the most important
conjunction with appropriate biologic
changes to the drug discovery
assays
the
process61-63. Screening of one
ethnomedical uses would be most
hundred thousand samples in a
that
correlate
with
appropriate.
7
routine
assay
now
61-63,
66-71
compound libraries
using 384-well formatting, a data
This is because Natural Product
handling system, and limited
extracts contain complex mixtures
robotics. This screening time can
of
be decreased further using higher
compounds, some of which have
density formats and advanced
undesirable properties. An added
robotics61,64,65.
of
mostly
.
uncharacterized
Therefore,
the
complication is that interfering
compounds
or
compounds may be present in
extracts that can be screened for
the
each drug target is generally not
compounds of interest, which
the rate-limiting step.
may mask the biological effect.
The decision when to screen
Compounds
Natural
extracts
compounds also may be present
compared to compound libraries
in an extract, which can interfere
is extremely important for the
with the screen in a nonspecific
successful integration of Natural
manner72.
Product
Product hits into a lead discovery
•
more problematic than screening
be
completed in just over a week
number
•
can
•
extract
in
addition
or
Traditionally,
families
crude
to
of
extracts
program. This is because no
have been used for screening, but
matter how quickly the active
the
compounds can be isolated and
available from HTS has enabled
their structures identified, there
the possibility of economically
will always be a lag time behind
screening prefractionated extracts.
the
pure
The prefractionation process can
compounds whose structure and
produce fractions that can range
method of synthesis is known at
from relatively crude fractions to
the onset. In fact, screening of
mixtures of only a few compounds.
Natural Product extracts well
The
before a synthetic library would
separation
be preferable, but in practice this
instruments has enabled some
rarely, if ever, happens.
companies to assemble large
The screening of Natural Product
libraries
extract
Products, which can then be
evaluation
libraries
of
is
generally
extra
screening
advent
of
sophisticated
and
of
capacity
pure
analytical
Natural
8
screened in a manner analogous
to
to pure compound libraries73-82.
contain the same or similar
The advantage of these libraries
unidentified compounds that are
is that no further purification is
responsible for the biological
generally
activity.
required,
which
like-extracts
This
that
grouping
of
enables active compounds to be
extracts with like dereplication
evaluated on an equivalent basis
profiles significantly reduces the
to synthetic compound libraries.
possibility of different chemists
The disadvantages are that it is a
independently
time-consuming
identifying
process
and
missed
using
an
isolation
isolating
the
same
and
active
component.
minor active components may be
•
group
•
The
bioassay
guided
strategy based solely on peak
fractionation procedure used to
collection.
There
identify
significant
cost
is
also
involved
a
in
bioactive
natural
products is often perceived as
preparation and screening of the
rate
extra
intensive. However, the rapid
fractions
generated
by
limiting
and
resource
prefractionation.
improvement of instrumentation
Dereplication is the process of
and
identifying known compounds
revolutionize other aspects of
that are responsible for the
drug discovery can also be used
activity of an extract before
to improve the speed of the
bioassay-guided
isolation
started69,
83-86
isolation
has
. The dereplication
process, which has been an
ongoing
concern
Product
chemistry
in
Natural
since
the
robotics
used
and
to
structure
elucidation of Natural Products.
The
advent
technology
of
87
new
and
probe
higher
magnetic fields has led to a
beginning of antibiotic research,
significant
is used to eliminate, group, and/
acquisition time for NMR data,
or prioritize extracts for further
and the structure elucidation of
study and can save considerable
Natural Products can be achieved
research time. The dereplication
routinely on amounts less than 1
procedure also can be extended
mg.
88
shortening
in
. Progress has also been
9
made in automated structure
solving
,
Crude herbs/plants (various plant
but
parts and exudates) are mostly
presently none can rival the
formulated as tablet and capsule
structure elucidation skills of an
and to some extent as oral liquid
experienced
preparations.
chemist.
•
89-91
algorithms
•
Natural
Product
However,
these
These
dosage
forms are not successful due to
programs can be a valuable tool
problems
to search for alternative structures
absorption, therapeutic efficacy
that fit the same NMR data.
and poor compliance.
The biggest obstacle to Natural
Product
chemistry
continuous
amounts
is
supply
of
in
Tablet or capsule dosage form
the
requires powdering of crude
large
herbs and particle size affects the
Product
process of blending, compression
of
Natural
•
encountered
required for further biological
and
evaluation. The identification of
homogeneity
a sustainable source of the
achieve due to the handling of
Natural Product needs to be
large
addressed if a semisynthesis or
moisture content and inherent
total synthesis is not available.
nature of raw materials (crude
This is not so much trouble if
drug).
there is a microbial source of the
difficult to formulate in solid
compound.
dosage
A
systematic
filling.
bulk
In
is
difficult
quantities,
Crude
forms
addition,
extracts
due
to
to
high
are
their
approach called OSMAC (one
hygroscopic nature, poor solubility
strain-many
and stickiness.
compounds)
to
increase the yield and diversity
of
compounds
produced
by
microorganisms was proposed
by
Zeeck
while
and
advances
co-workers92,
are
being
•
As drug discovery from plants
has
traditionally
been
time-
consuming, faster and better
methodologies
for
plant
collection, bioassay screening,
achieved rapidly in the area of
compound
microbial
compound development must be
combinatorial
93
biosynthesis .
isolation
and
employed 94.
10
•
Innovative strategies to improve
group like-extracts. Some other
the process of plant collection
new screening methods64 include
are needed, especially with the
the novel microarray compound
legal
issues
screening (microARCS) technology,
benefit-sharing
which utilizes agarose matrixes
and
political
surrounding
•
agreements95,96.
to introduce a majority of the
The design, determination and
reagents throughout the assay101,
implementation of appropriate,
and on-line biochemical detection
clinically
high-
coupled to mass spectrometry,
throughput bioassays are difficult
which already has been used for
processes for all drug discovery
the screening of natural products
programmes96,
extracts102.
relevant,
97
. Although the
design of high-throughput screening
•
•
Challenges in bioassay screening
assays can be challenging98, once
remain an important issue in the
a screening assay is in place,
future of drug discovery from
compound and extract libraries
medicinal plants. The speed of
can be tested for biological
active compound isolation can be
activity. The common problem
increased
faced
of
techniques like LCNMR and LC-
extracts is solubility and the
MS. Development of drugs from
screening of extract libraries is
lead compounds isolated from
many times problematic, but new
plants, faces unique challenges.
techniques
Natural products, in general, are
during
screening
including
pre-
using
hyphenated
fractionation of extracts can alleviate
typically
some of these issues94, 100.
quantities that are insufficient for
To get appropriate compound
lead optimization, lead development
from
and clinical trials. Thus, there is
screeing
of
Natural
isolated
in
small
a
a need to develop collaborations
complementary orthogonal assay
with synthetic and medicinal
or assays to remove as many
chemists
false positive hits as possible.
possibilities of its semi-synthesis
Dereplication can then be used to
or total synthesis103,104,105. One
remove nuisance compounds or
can also improve the natural
Products
is
to
design
to
explore
the
11
products compound development
development and is biochemical
by creating natural
probes
libraries
that
products
combine
discovery
of
process.
features of natural products with
•
the
pharmacological and biochemical
the
•
combinatorial chemistry.
for
Combining the strengths of the
With the dwindling population of
knowledge
taxonomists and rare introduction
systems such as ayurveda with the
of youngsters in this field, it
dramatic power of combinatorial
might take another 20–30 years
chemistry and HTS will help in the
with the current pace to survey
generation of structure–activity libraries.
the complete flora of the country.
•
base
Traditional
of
traditional
knowledge
and
Now the question before us is,
experiential database can provide
could
the
new functional leads to reduce time,
pharmaceutical potential of all
money and toxicity – the three main
the floristic components that we
hurdles in drug development. These
know? The answer is no.
records are particularly valuable,
we
assess
Future perspectives
since effectively these medicines
Despite several problems, one cannot
have been tested for thousands of
discount the past importance of plants as
years on people106.
sources of structurally novel drugs and it
•
Bioprospecting demands a number
provides a great opportunity to the
of requirements which should be co-
scientists in the field of Natural Product
coordinated,
Chemistry, Pharmacognosy, Pharmacology,
scientific
Ethnobotany and other related fields of
expertise in a wide range of human
life science to come together and work
endeavours, including international
in the direction of getting new drugs fro
laws and legal understanding, social
Natural Sources, especially from Plants
sciences, politics and anthropology.
for betterment of mankind.
•
•
Ayurveda
such
experts
and
as
team
along
other
of
with
traditional
The importance of natural products
systems of medicine, rich genetic
in the future of drug discovery is
resources
clear:
ethnomedical knowledge are key
novel biologically active
and
associated
natural products will continue to
components
serve as lead compounds for drug
bioprospecting and value-addition
for
sustainable
12
processes.
•
extracts. Globally, there is a need to
build
is needed, which will be instrumental in
libraries. The extract libraries offer
converting the discovery into a
various
commercial product.
reduction in cost and time for repeat
Important in any bioprospecting is
collection of plants and availability
the drafting and signing of an
of properly encoded and preserved
agreement
extracts
or
Memorandum
of
natural
products
advantages,
in
large
extract
such
numbers
as
for
Understanding that should cover
biological screening in terms of
issues on access to the genetic
high-throughput
resources
obtaining hits within a short period.
(biodiversity),
property
on
related
to
•
screenings
and
Innovation and creativity regarding
discovery, on the sharing of benefits
the molecular scaffolds will be
as part of the process (short term),
substantially
and in the event of discovery and
discovery of relatively simple, small
commercialization of a product (long
molecular weight bioactive natural
term), as well as on the conservation
products. Combinatorial approach
of the biological resources for the
with a nucleus that is already known
future generations.
to
When
ethnobotanical
with
exciting
the
biological
activity will increase the likelihood
or
of
utilized,
candidate.
additional
enhanced
possess
ethnopharmacological approach is
specific
creating
interesting
Similarly,
drug
mixing
of
requirements that relate to prior
genetic information encoding for
informed consent, recognition of
specific secondary metabolites may
Indigenous Intellectual Property and
produce “unnatural” natural products
Indigenous
with specific therapeutic activity 109.
Intellectual
Property
Rights as well as short- and long-
CONCLUSION
term benefit sharing need to be taken
Ethnomedicine may be defined broadly
into account
•
drug-targeted
bioprospecting an industrial partner
intellectual
•
For
107, 108
.
as the use of plants by humans as
In order to screen thousands of plant
medicines
species at one go for as many
medicine is a broad term used to define
bioassays as possible, we must have
any
a collection of a large number of
Ethnopharmacology
where
non-Western
as
Traditional
medical
is
a
practice.
highly
13
diversified approach to drug discovery
elucidation,
involving the observation, description,
processes and prudent selection of drug
and
targets for the screening of Natural
experimental
investigation
of
and
indigenous drugs and their biologic
Product libraries.
activities.
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