19 International Journal of Natural Products Research 2014; 4(1): 19-32
ISSN: 2249-0353
Original Article
NATURAL PRODUCT RESEARCH ISSUES, OPPORTUNITIES AND CURRENT
PRIORITIES IN NIGERIA
*UGOALA EMEKA, 1NDUKWE GEORGE ILOEGBUNAM,
2AYO RACHAEL GBEKELE-OLUWA and
3MUSTAPHA BOLA
Fisheries Products’ Development Programme, National Institute for Freshwater Fisheries Research, P.M.B. 6006,
New Bussa 913003, Niger State, Nigeria 1Department of Chemistry, Faculty of Science, Ahmadu Bello University, Zaria
2Samaru College of Agriculture, Division of Agricultural Colleges, Ahmadu Bello University, Zaria
3National Institute for Pharmaceutical Research, Abuja
* Corresponding author: [email protected]
Received 10 January 2014; Accepted 20 March 2014
Abstract
Natural products represent an unparalleled source of molecular diversity to drug discovery, and are complementary to other
molecular sources, such as synthetic chemical collection and combinatorial libraries. There are thousands of natural
chemical constituents of plants and animals that are beneficial to man. However, challenges in natural product drug
discovery are significant. Issues in drug development are increasingly complex, and development hurdles are high. There
should be an increasing focus and effort on drug development to ensure successful natural product drug development and
reduce the attrition rate of drug candidates by enhancing the quality of discovery compounds that lack major liabilities,
especially toxicity. It is thus essential to adopt a multidisciplinary approach when working in this field.
© 2014 Universal Research Publications. All rights reserved
Key words-:-Chemotherapeutic Agents; Chemical screening methods, Natural products Research
INTRODUCTION
Nature has been a source of medicinal agents for thousands
of years and an impressive number of modern drugs have
been isolated from natural sources. Although many have
been superseded by conventional pharmaceutical
approaches, there is currently a resurgence of interest in the
use of natural bioactive products by the general public.
Natural products are active plants/ animal constituents
which have biochemical effects. They are usually
synthesized in the body of the containing organism as
secondary metabolites.
Natural products study is truly an interdisciplinary
field of research. Chemistry is necessary to understand and
interrogate the numerous structures encountered.
Enyzmology is needed to study the enzymes that are
critical in biosynthesis and protein interactions that
facilitate binding activity between other molecules, and
pathogens. Fundamental biological research is needed to
identify biological pathways and functions. Research areas
related to or encompassed by natural products include
glycobiology, carbohydrate chemistry, synthetic and
biosynthetic chemistry, bioinformatics, microbiology,
genetics, genomics, proteomics, lipidomics, metabolomics,
immunology, reproductive biology, drug development,
systems biology, bio-energy and bio-products, and
developmental biology. Natural products therefore play
major roles in biological functions and are involved in all
phases of life.
While natural products have produced
unparalleled discoveries that have advanced the
understanding of biological processes, the picture these
present is incomplete. It is thought that on-going study of
natural products in plants, microbes, and animals could lead
to the next level of discoveries that may help treat and cure
diseases, develop new platforms for energy, and gain a
fundamental understanding of life. In today‟s health
conscious society more people are interested in the effects
of nutrients on human health.
Research support for natural products in Nigeria
comes primarily from federal funding agencies. These
research centres do not run collaborative research that has
the potential to generate large impacts across emerging
applications in human health and in areas such as the
development of new bio-energy and bio-product resources.
Also lack of adequate infrastructure and equipments hinder
scientists from making huge leaps forward in research.
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20 International Journal of Natural Products Research 2014; 4(1): 19-32
Such infrastructure included techniques for the rapid
expansion of nucleic acid material, rapid, automated and
cost‐effective nucleic acid sequencing and significant
computational advances enabling dynamic simulations of
protein and nucleic acid interactions. The complexity of
natural products makes the development of quick and
inexpensive methods significantly more difficult and
accessible to both students and other scientists.
There is need for more systematic and
comprehensive education on natural products, at multiple
educational levels, to raise awareness among students and
scientists of the fundamental roles played by natural
products in almost every aspect of biology, and to stimulate
interest in the field. Natural products importance has not
translated into widespread incorporation into core
educational curricula. The extent to which carbohydrates
are incorporated into courses reportedly varies by school,
as do the primary departments in which it is taught. The
interests and research of faculty members influence the
natural products topics that are covered. Traditional
departmental divisions may be a barrier to widespread
inclusion of a highly cross‐ disciplinary field. Organic
chemistry classes frequently focus on petroleum‐ based
hydrocarbons as a starting material, while biochemistry
classes often focus heavily on memorization of metabolic
pathways. As a result, there may be missed opportunities to
incorporate content on natural product or the field may be
perceived as boring by students. Undergraduates commonly
receive only limited exposure to natural products, and the
field is also poorly covered by most graduate and medical
schools. Generally, there is a “high activation barrier” for
many scientists to delve more deeply into natural products
because current research requires a significant biochemistry
background and collaborations with specialized chemists.
There are roles to be played by professional societies,
journal editors, and scientific meeting organizers to help
showcase interesting and important aspects of natural
products. Review articles, plenary talks, and seminars could
be potential ways to help raise the profile of the field and to
highlight the breadth and importance of natural products,
especially among less specialized scientific audiences. This
initiated the current investigation. As well as to identify key
areas of natural products research with potential for
commercial exploitation and to promote natural products
research as part of initial R&D rather than an „add-on‟ –
ensuring future sustainability.
IMPORTANCE OF NATURAL PRODUCTS
HUMAN HEALTH
Neglected tropical diseases are major health concern in
developing countries of the world. Most of neglected
tropical diseases seriously affect almost exclusively poor
population living in developing counties. These neglected
tropical diseases are caused by parasites, which are spread
by insects‟ vectors or contact with contaminated water or
soil. Over one billion people are the victims of parasitic
disease including malaria. Unfortunately there is serious
lack of interest in the research and control of these diseases.
More so, in developing countries the cost of research and
development of synthetic drugs is prohibitive and
technological facilities are lacking. Most of the
multinational pharmaceutical companies are not interested
in developing drugs against such tropical diseases. Since
investment on control of these diseases is considered to be
non profitable. Therefore, there is an urgent need to
develop new drugs and vaccines that are adapted to
developing countries‟ needs, and to make them available at
affordable prices for common people.
Therefore natural products are being developed as
dietary supplements, phytomedicine and nutraceuticals.
Also standards and monographs for the establishment of
efficacy and safety of herbal medicines, certification of
medicinal and aromatic plants, and commercialization of
research based products, standardization and quality
assurance of herbal medicine products and technologies are
on-going in the following fields:
Herbal Medicines/Remedies and Medicinal and
Aromatic Plants Products: traditional medicines,
whole plants, extract, tinctures, etc
Health, Cosmetics and Beauty Products: Natural
toothpaste, Soaps, Dyes, Hair, beauty and skin care
products
Health Foods and Food Ingredients: Fruits, nuts,
colouring and flavouring materials; Fruit drinks/juices;
health snacks; Spices
Vegetable Saps and Extracts: Shea butter; Lacs;
natural gums, resins, gum-resins and balsams; Honey,
Peanut, Coconut, Palm kernel oil (not chemically
modified); Vegetable and Animal Fats and Oils;
Waxes; Cocoa butter, fat and oil; Colouring matter of
vegetable or animal origin
Natural bioactive products are regarded as being
highly effective, possess low toxicity, have a minor
environmental impact and need not to be certified before
use. This is a common misconception not borne out by the
research evidence.
Natural toxins in food can be just as dangerous as
synthetic ones. Since we only consume very small amounts
of each of the different toxic compounds at any one time,
our livers can process the toxins and they are broken down
by a range of metabolic pathways. However, the ability of a
natural compound to affect an individual or population
would depend on a number of factors, including the
potency or efficacy of the compound, its concentration,
duration of exposure, bio-concentration potential, presence
of other compounds, life stage exposed, season, other
environmental stressors present (e.g., temperature, salinity,
and other contaminants), and mobility of the individual.
AQUACULTURE AND ANIMAL PRODUCTION
Fish culture and animal production are being hampered by
the high cost and scarcity of inputs such as antibiotics,
anesthetics, tranquilisers, hormones and other chemicals
needed for successful production. Synthetic compounds
with estrogenic activity disrupt normal endocrine function
in wildlife populations and humans. These have created
interest in the development of alternatives including the re-
examination of using plant derivatives. Therefore natural
immune stimulants like glucans, chitin and chitosan,
vitamin C and E, some polysaccharides and polyribo-
nucleotide are being used to replace chemotherapeutic
21 International Journal of Natural Products Research 2014; 4(1): 19-32
Table 1: Toxic compounds in some natural products
Source Effects
Heterocyclic amines
1. 2-amino-3-methylimidazo [4,5-f]
quinoline (IQ)
2. 2-amino-3,8-dimethylimidazo
[4,5-f]quinoxaline (MeIQx)
3. 2-amino-3,4,8-trimethylimidazo
[4,5-f]quinoxaline (DiMeIOx)
4. 2-amino-1-methyl-6-
phenylimidazo[4,5-f]pyridine
(PhIP)
Proteins and Lipids 1. Tumor-promoting agent or condition
2. DNA damage
Maillard Reaction Products Carbohydrates
1. Antioxidants
2. Anti-nutritional
3. Aroma formation
4. Encourage the loss of amino acids (lysine)
5. Scavenging of active O2
6. Changes in chemical structures of carcinogens
7. Risks for vascular system and kidney in diabetics
Conalbumin and avidin Egg protein Binds to biotin and can impair metabolism of other B-
vitamins
Solanine and Chaconine Potatoes Toxic
Cyanogenic glycosides Lima beans, cassava, apricot
kernels Release cyanide when in contact with stomach acids
Canavanine Alfalfa sprouts Causes severe lupus erythematosus; an autoimmune
disease
Pyrrolizidine alkaloids Herbal teas Carcinogenic, Mutagenic and Teratogenic (birth
defects)
Gossypol Cottonseed 1. Causes abnormal sperm and male sterility
2. Carcinogenic
Allyl isothiocyanate Mustard, garlic Carcinogenic
Piperine and Capsaicin Pepper 1. Tumors
2. Mutagencity
Psoralens Parsnips Potent light-activated carcinogens and mutagens not
destroyed by heat
Oxalates Spinach Inhibits calcium absorption
Myristicin Parsley and carrots large quantities can cause hallucinations, liver damage
and even death
agents. Natural carotenoids (astaxanthin and canthaxanthin)
are used as pigments and as a quality index of marketedfish
(Ingemansson et al., 1993). Natural plant product promotes
various activities such as anti-stress, growth promotion,
appetite stimulation, antifertility, immune-stimulation,
adaptogenic actions, aphrodisiac and antimicrobial
properties as shown below.
Fertility control agent, pawpaw seed (Udoh and
Kehinde, 1999; Uche-Nwachi et al., 2001; Ekanem
and Okoronkwo, 2003; Jegede et al., 2008); Garcinia
kola (Dada and Ajilore, 2009); Lophira lanceolata
extract (Etuk and Muhammad, 2009); Ovulation,
Oestrous cycle and foetal development (Akpantah et
al., 2005)
Neem (Azadirachta indica) leaf as reproduction
inhibitor (Jegede and Fagbenro, 2008)
Toxicity of African locust bean extracts (Ahmed et
al., 2005)
Growth promoter (Adedeji et al., 2006)
Erythropoietic and Anti-Obesity effects Garcinia
cambogia (Adesanya et al., 2007)
Kigelia africana as a testicular damage reversal
(Abioye et al., 2003).
Kigelia africana as Analgesic and anti-inflammatory
agent (Owolabi and Omogbai, 2007)
Agro industrial waste as feedstuff (Falaye, 1992)
Feather meal as a protein source (Ayanwale, 2006)
Cassava starch as feed binder (Orire et al., 2001);
duckweed (in dried, powdered and pelleted forms) as
feed preservative (Mbagwu and Adeniji, 1998). NATURAL PRODUCTS DEVELOPMENT AGENCIES
IN NIGERIA
Association for the Promotion of Traditional Medicine
(PROMETRA)
Raw Materials Research and Development Council
(RMRDC)
National Association of Traditional Medicine Practitioners
(NANTMP)
National Biotechnology Development Agency (NABDA)
22 International Journal of Natural Products Research 2014; 4(1): 19-32
Nigerian Natural Medicine Development Company
(NMDC) is to research, collate, document, develop,
preserve and promote Nigeria‟s Natural Medicine defined
as indigenous (traditional) health systems, medication and
non–medication healing arts, sciences and technologies to
assist contribute to improved healthcare delivery, wealth
and job creation and national economic growth and
development.
Conducting extensive Ethno-medicinal and Veterinary
Surveys aimed at the development of a comprehensive
inventory of the national MAPs
Developing a Dedicated Herbarium and Experimental
farms nationwide
Developing in volumes Comprehensive National
Inventory of Medicinal, Aromatic and Pesticidal Plants
in Books titled Medicinal Plants of Nigeria covering
the 6 geo – political zones and publication of the Book
of Abstracts (published research findings)
Training of TMPs to enhance products and practices
that will enable them play active part in the bio-
business sector
Developing a Laboratory, Pilot Product Development
Unit (PDU) and Development of Process Technologies
for the primary efficacy and safety analysis of Herbal
therapies to assist provide scientific and technical
assistance to TMP entrepreneurs and health food
producers
Developing Digital Virtual Library – A dedicated
Focal Reference Centre which for the development and
promotion of traditional medicine as well as promote
e-commerce.
Nigerian Stored Products Research Institute (NSPRI) is
mandated to carry out research into bulk storage problems
of export commodities and food crops and in particular to
conduct research into:
Improvement and maintenance of bulk export
commodity crops including cocoa, groundnuts, palm
[produce (kernel and oil) etc
Improvement and maintenance of the quality of food
crops including cereal grains, pulses, tubers and any
other local commodity under bulk storage.
Special studies such as stored products pest, pesticide
formulations residues and mycotoxins.
Provision of advice and training of extension workers
in problems associated with stored products and
materials used in storage and pest control including
storage structures, new items of equipment and new
technologies.
National Veterinary Research Institute (NVRI) conduct
research into all aspects of animal diseases, their Treatment
and Control; To Develop and Produce animal Vaccines,
Sera and Biological to meet the National demand; To
provide Surveillance and Diagnosis of animal diseases; To
introduce Exotic Stock for improved egg, meat and milk
production
National Horticultural Research Institute (NIHORT) Conducts research into fruits, vegetables, their processing
and preservation and development of indigenous
ornamentals plants
National Institute for Pharmaceutical Research and
Development (NIPRD) is mandated to carry out research
and development of drugs and pharmaceutical substances
from locally available natural resources, ensure the quality
of drugs in circulation in the country: encourage the
development of herbal and traditional medicines by proper
documentation, verification and standardization of such
preparations; serve as a National Centre for Drug
Information
The Nigerian Institute for Trypanosomiasis Research
(NITR) is conduct research and development for the
control and eradication of Trypanosomiasis and
Onchocerciasis in all the geo-ecological zones of Nigeria.
National Root Crops Research Institute (NRCRI) is
primarily concerned with researches into yams, cassava,
cocoyam, Irish potatoes, sweet potatoes and ginger.
Cocoa Research Institute of Nigeria (CRIN) focuses on
cocoa, kola, cashew, coffee and tea. Also involved in the
improvement of the genetic potential, agronomic and
husbandry practices, including processing and storage of
the crops; Identification of the ecology and methods of
control of pests and diseases affecting the crops;
Investigating the effective utilization of the crops and their
by-products, and the feasibility of small-scale production of
such end-use products.
Institute for Advanced Medical Research and Training (IAMRAT) involved in research of international standard
channelled towards solving relevant local and international
health related problems.
Studies on Molecular markers of resistance to anti-
malarial drugs such as Pfindr, Pfcrt, dhfr, dhps etc.
Factors affecting genetic associations with the
resistance phenotype.
Identification and evaluation of active natural products
for malaria therapy
In-vivo and In-vitro evaluation of anti-malarial
activities of drugs and natural products.
Drug disposition and pharmacokinetics of anti-malaria
agents including chloroquine, amodiaquine, quinine
and dihydro-artemisinin.
Toxicological studies of novel and conventional anti-
malarial agents.
Establishment of standard Ethno medical erbarium.
Extraction, isolation and development of pure
compounds having anti microbial, antitumour, anti-
malaria and anti viral properties from plants.
Formulation of active compounds into dosage forms.
National Centre for Genetic Resources and
Biotechnology (NACGRAB) is mandated to perform the
following functions so as to contribute to the realization of
government aspirations in national development.
Acquisition, maintenance, exchange and utilization of
microbial cultures.
Development of facilities, the identification of national
research needs and priorities and the conduct of
research in conservation and utilization of genetic
resources.
Acquisition of germplasm, their conservation for
posterity and immediate utilisation to rapidly transform
our agriculture and industry, improve the local
23 International Journal of Natural Products Research 2014; 4(1): 19-32
sourcing of drugs that are of plant origin and help in
the amelioration of harsh environments
National Animal Production Research Institute
(NAPRI) is to conduct Applied Research on food animal
species as well as forage, and to develop appropriate
technologies in breeding and reproduction, nutrition and
management with the ultimate and of improving the
productivity of the animals for milk, meat, eggs, traction
power etc.
National Research Institute for Chemical Technology (NARICT) is mandated to develop the technologies
required by the chemicals industry and shall undertake
research and development work into:
Processes for the conversion of agricultural, mineral
and other raw materials into chemicals; The processing
of commercial grade chemicals to laboratory grades;
The derivation of secondary chemicals from
petrochemicals, coal chemicals, etc.
The production of functional polymers and engineering
plastics, their characterization and utilization;
The processing of hides and skins into leather
products, and the processing of natural man-made
fibres.
National Institute for Freshwater Fisheries Research (NIFFR) is to research into fresh water fisheries and other
aquatic resources in rivers, natural and man-made lakes.
National Cereals Research Institute (NCRI) conducts
research into rice, soya-beans, beniseed and sugarcane
Nigerian Institute for Oil Palm Research (NIFOR) is to
conduct research into the production and products of oil
palm and other palms of economic importance.
Forestry Research Institute of Nigeria is charged with
the mandate to conduct research into all aspects of forestry
and forest products utilization and for the training of
technical and sub technical personnel for the forestry
services in the country
Federal Institute of Industrial Research (FIIRO)
To conserve Nigeria„s foreign exchange earnings by
reducing dependence on foreign goods, through the
development of local substitutes from locally available
raw materials.
To improve the nutritional qualities of Nigerian foods,
which are known to be deficient in the essential body -
building food properties.
Institute of Agricultural Research and Training (IART)
conducts research on various cereals and legumes such as
maize, jute, kenaf and sisal hemp
NATURAL PRODUCTS RESEARCH NETWORKS IN
AFRICA
International Centre for Ethno medicine and Drug
Development (InterCEDD) is a leading research,
development, and analytic laboratory that provide product
development, training, quality assurance and pilot
manufacturing service to scientists, traditional medicine
practitioners, institutions and pharmaceutical. InterCEDD
also buys raw materials from farmers, agro business owners
that are able to produce or supply select agro produce for
novel natural products as dietary supplements,
phytomedicines and nutraceuticals product development
purposes.
Botanical Standardization
Processing and standardization of Herbal Products
Complete analytical testing
Natural products extraction, isolation and purification;
Access to a full herbarium and ethno botanical
database;
Formulation/reformulation of Herbal Products
Biological assays
Laboratory evaluation of herbal products
Training
Natural Products Research Network for East and
Central Africa (NAPRECA) is to initiate, develop and
promote research in the area of natural products in the
countries in Central and Eastern Africa sub-region and to
coordinate and maintain inter- and intra-regional links
among different research groups. The countries in this
Network are Botswana, Cameroon, Democratic Republic of
Congo, Ethiopia, Kenya, Madagascar, Rwanda, South
Africa, Sudan and Uganda.
Network for Analytical and Bioassay Services (NABSA) is a network of laboratories in the Chemistry Departments
of three East African Universities, namely, Addis Ababa
University in Ethiopia, University of Nairobi in Kenya and
University of Botswana located in Gaborone, Botswana.
The purpose was to find ways of assisting scientists
working in isolation and in various institutions in Africa
who were constrained because of inadequate facilities and
less enabling environments.
NABSA was created to encourage phytochemical
research underpinned with bioassay of natural products, by
pooling existing analytical facilities in African research
laboratories. Its objective is to "promote closer cooperation
among African scientists and institutions in order to reduce
undue dependence on the North and to enhance the growth
of science in Africa by mutual assistance, sharing and
effective utilization of available facilities in the continent."
NABSA also provides for short-term research visits.
Research scientists from various countries on the continent
can also access these services by sending samples for
analysis after prior approval of the Coordinator.
Western Africa Network of Natural Products Research
Scientists (WANNPRES) medicinal plant research focus
on Malaria and other parasitic diseases, HIV/AIDS, and
Maternal and Child Health diseases, especially
malnutrition. The emphasis is on finding the scientific basis
for the cure of medicinal plants and their products; be they
crude extracts, fractions of these extracts or the pure
compounds isolated from them. Validation of the medicinal
effects of herbs to corroborate the claims of herbalists
forms a large part of the research agenda of WANNPRES.
Characterization of isolated chemical compounds is an
important component of the research but it is not the
flagship project of the Network.
African Network of Drug and Diagnostics Innovation
(ANDI) was set up to address the problem of less spending
on health product discovery and development in Africa by
increasing and strengthening networks throughout Africa
that would build capacity from early drug discovery and
development right through to manufacturing. There was a
felt need for African-based solutions to African problems,
24 International Journal of Natural Products Research 2014; 4(1): 19-32
with the involvement of African-based institutions and
researchers capable of identifying the priorities and doing
the work.
The network would focus on research for new
drugs and diagnostic tools for the diseases and health
problems most affecting Africa. Most African-based
researchers hardly communicate with their colleagues due
in large part to the lack of financial and organizational
support to link researchers throughout the continent. ANDI
would strengthen these intra-continental links, providing
funding for networked collaborative research across
countries, as well as supporting IT infrastructure and the
negotiation and management of intellectual property rights,
including patents.
West African Health Organisation Committee of
Traditional Medicine Experts is primarily to promote
traditional medicine agenda that aims at ensuring the
institutionalization of traditional medicine in the health
systems of Member States. However, it also promotes
traditional medicine research expertise in the sub-region
because of the way it operates.
African Association of Medicinal Plant Standards
(AAMPS) was established to address the lack of suitable
technical specifications and quality control standards for
African medicinal plants and herbal medicines which was
identified as a major constraint and a significant barrier to
regional and international trade and to integrating
traditional medicine into African public health services. Its
objectivities include
Developing quality control and quality assurance
standards for African medicinal plants and herbal
medicines to support the African herbal industry and
regulatory authorities.
offering membership of the newly formed association
to any individual or organisations dedicated to the
establishment of such standards and to the creation of
an African Herbal Pharmacopoeia
preparing and publishing an African Herbal
Pharmacopoeia based upon 50 herbal profiles and
promoting its use nationally and internationally
helping to obtain international validation for these
herbal standards and the subsequent herbal
pharmacopoeia and to lobby health authorities
throughout Africa to use such standards as the basis for
licensing safe and effective herbal medicines in Africa
Promoting capacity building in Africa for the
establishment of regional training centres for
certification, compliance and quality control of herbal
medicines.
promoting the safe, sustainable national and
international trade in the fifty profiled African
medicinal plants
Historically healthcare delivery, food, beverages, as
well as health and beauty products especially in Africa had
been supported by the indigenous flora and fauna. Nigeria
is blessed with a vast and diverse biodiversity and bio-
resources as well as enormous traditional (indigenous)
medical knowledge. Today, the renewed global focus
supported with emergence of new technologies is arguably
on the sustainable utilization of plants and genetic materials
in the development of new products in the agricultural,
food, pharmaceutical and cosmetics industry. This
represents tremendous opportunities for natural products
manufacturers in Nigeria to maximize these potentials for
improved quality of life and national economic growth and
development.
CURRENT RESEARCH ACTIVITIES
PHYTOCHEMICAL SCREENING
Screening of the chemical constituents of plants has been
the major route for research in natural products in Nigeria.
Biologically active (antimicrobial, anti-inflammatory, anti-
angionic, analgesic, anti-allergic, cytostatic and antioxidant
properties) substances are extracted through the traditional
techniques (solvent-solvent). The principle behind the
extraction is that molecules of the same polarity will follow
solvents of the same polarity. The traditional extraction
methods used to obtain these type of products have several
drawbacks; they are time consuming, laborious, have low
selectivity and/or low extraction yields. Moreover, these
traditional techniques employ large amounts of toxic
solvents.
Structures were elucidated mainly using one and
two dimensional NMR techniques with additional
parameters such as optical rotation, UV and IR properties.
Identity of isolated compounds with compounds reported in
literature was judged, if not stated otherwise, based on 1H
and 13C NMR spectroscopic data. Literature searches are
usually done using Chapman and Hall Natural Products on
CD-ROM and Beilstein on-line databases. Structures are
designated as new, if they could not be found in Beilstein
database and Chemical Abstracts.
The modern natural product research is
undergoing a revolution due to recent advancements in
combinatorial biosynthesis, microbial genomics and
screening processes. Moreover, access to hyphenated
techniques like Liquid Chromatography-Mass
Spectrometry, Liquid Chromatography-Nuclear Magnetic
Resonance as well as X-ray crystallography have raised the
hope of drastically reducing the time and cost involved in
natural product research by using de-replication processes
that are combination of techniques to avoid the already
reported compounds. Promising technology is also found in
supercritical fluid extraction (SFE) with natural CO2 for the
recovery of valuable compounds. This technique of
extraction is environmentally friendly solvent-free
extraction method as well as non-expensive method that
results in minimal oxidative and thermal stress. SFE aids
the extraction of high-value substances as well as aromas in
their natural composition.
MOST RESEARCHED ENVIRONMENT
The terrestrial environment has been a major source of
medicinal plants for thousands of years and many bioactive
compounds have been isolated. Many of these isolations
were based on the uses of the agents in traditional
medicine. The use of traditional medicines and medicinal
plants in most developing countries as therapeutic agents
for the maintenance of good health is widely observed.
Interest in medicinal plants as a re-emerging health aid has
been fuelled by the rising costs of prescription drugs in the
maintenance of personal health and well being and the bio-
25 International Journal of Natural Products Research 2014; 4(1): 19-32
prospecting of new plant-derived drugs, escalating faith in
herbal medicine, the extraction and development of drugs
and chemotherapeutics from these plants as well as from
traditionally used herbal remedies.
However, the instant rising demand of terrestrial
plant-based drugs is unfortunately creating heavy pressure
on some selected high-value medicinal plant populations in
the wild due to over-harvesting. Several of these medicinal
plant species have slow growth rates, low population
densities, and narrow geographic ranges; therefore they are
more prone to extinction.
Several life-saving drugs have been developed
from the extracted biochemical of terrestrial plants. Aquatic
plants are of considerable interest as a new promising
source for bioactive substances. They have been recognized
as an untapped resource for novel bioactive compounds.
Several natural products obtained from aquatic organisms
have proven to be rich sources of novel compounds
exhibiting many different biological activities. The lush
tropical rainforests and colourful coral reefs of our planet
have long been a source of promise in the fight against
diseases. They house an amazing biodiversity of microbial,
plant and animal life which produces a dizzying array of
protective chemicals. Therefore, the development and
adoption of hydraulic engineering to access estuarines,
creeks and wetlands into vast pens for culturing these
organisms is most needed.
Problems with Field Collected Material
Very few bioactive biomass can be collected in large
amounts (Blunden, 1989).
Collecting from the environment requires considerable
time and effort (Shakira, 2007).
Harvesting of large quantities requires the consent of
the country where the collection is made and must be
carefully evaluated not to adversely impact collection
site.
Lack of reproducibility: Secondary metabolite
production in field materials unpredictable, many
biomass prove to be non active on recollection while
bioactivity may vary within a few meters at the
collection site (Neushul, 1990; Witvrouw and De
Clercq, 1997).
Research and development of biomass from natural
resources cannot rely on field collected materials.
Advantages of Culturing
Some active strains may be very rare in the field and
thus their bioactivity is overlooked. We can find them
through enrichment, isolation and cultivation (Shi et
al., 2000).
Synthesis of biomass is dependent on culture
conditions (temperature, pH, light, nutrients).We can
stabilize production of the active molecule by
controlling culture conditions. Genetic manipulation is
also possible (Chisti, 2007; Paul et al., 2009).
Selection criteria for cultivated organisms used as
Industrial Resources
High yield and agronomy to avoid high production costs (cultivars of species will be generally better than wild
species). Culture conditions could be improved by use of
technologies, such as cryo-conservation, for the creation of
culture collections which can be screened to identify new
commercially interesting lines. Establishing a research
platform in this area could increase the commercial activity
and strains used for new compound discovery and provide
longer-term economic returns from public-sector
investment.
Ease of processability (to avoid the need of developing
new technologies and infrastructure). There are
opportunities to engineer plant strains more suited to
downstream processing (e.g. altered cell walls properties).
The application of new physical or biological methods
could also help improve process efficiencies.
The utility and value of by-products Opportunities exist
to integrate production and processing of resource around
current industrial infrastructure and market-driven needs.
This would allow by-products from other industrial
processes to be integrated into production systems. There is
a need to move towards proof-of-concept to stimulate
commercial uptake and help de-risk investment from
industry. Establishing a joint-call for commercialisation
programmes for bio-energy, chemicals and feed production
would help take advantage of the research-base and
industry strength in this area. By-products could be used as
a protein-enriched source of animal feed or to capture
energy within the system e.g. through anaerobic digestion
for CH4 production.
Identity preservation and out-crossing from non-
food crop (to ensure that industrial products do not enter
the food chain). Microalgae have Advantages than
conventional agricultural crops. Microalgae represent the
start of the food chain, and so are less likely to acquire
toxins such as heavy metals.
Fast track organism breeding and selection methods If
the exploration of natural biodiversity can reveal interesting
new species, their use should pass through a development
phase to increase the growth rate – natural species present a
rate of proliferation far inferior to other more developed
species. Three techniques are of note:
Natural selection in controlled conditions - this area
meets general approval despite restrictions on the rate
of multiplication. Strong pressures of selection permit
the populations to become uniform in the case of
continual culture.
Selection from populations submitted to mutagenic
agents and GMO – this area has been little developed
but could be used to develop strains with defined
performance characteristics for a variety of high-value
industry applications. Genetic transformation is the
only way to produce certain bio-products, but there
will be environmental, ethical and societal
considerations to how these are used.
Exploration of natural diversity – this area would
provide opportunities for discovery of new metabolic
pathways and metabolites. Genetic transformation of
these pathways to other more robust industrial
organisms has been used as an effective way for
synthesis at scale, but is not the only way to achieve
synthesis of certain bio-products e.g. where symbiosis
is necessary for production of bioactives/metabolites.
26 International Journal of Natural Products Research 2014; 4(1): 19-32
Suitability for genetic engineering
RESEARCH ISSUES/NEEDS
PHYSICAL CONSTRAINTS TO LARGE SCALE
BIOMASS GENERATION
Increasing World population
The use of energy crops (perennial grasses and trees grown
on agricultural land) as source for bioactive molecules
could drive up prices of both food and land due to
increasing population. The price increases could affect
impoverished populations in developing countries, in
particular. Although the total amount of terrestrial plants
now being used may never be accurately estimated, its
future use are limited by the availability of land to grow
trees and other plant materials.
Biomass Generation in Theory and Practice
The central part of the solar spectrum is photosynthetically
active radiation. Only 45 % of solar radiation energy is
carried by this part of the spectrum. A further reduction of
biological solar energy conversion efficiency is due to the
fact that some of the qualified photons absorbed by the
plant fail to perform photosynthesis; the quantum
efficiency about 25 %, which reduces the conversion
efficiency to about 11 %. In addition, some of the solar
radiation is reflected, and photosynthesis requires
respiration which requires energy. Thus, a realistic
expectation for the efficiency by which solar radiation
energy can be converted into biomass is about 3-6 %
(Kazuhisa, 1992). This theoretical efficiency is 10 times
lower than the technical conversion efficiency. Hence a
very large area of biologically productive land is required
to supply a significant proportion of biomass needs for
bimolecular extraction.
Global limits to Food and Energy Crops
A study of net primary productivity for the world Lieth,
(1975), confirms the low efficiency of biological
conversion of solar energy; only tropical rainforests and
wetlands generate biomass at some appreciable rate; other
forms of vegetation have lower yields. According to Lieth
1.4*1013
m2 of land worldwide is cultivated or used for
permanent crops; this amounts to 2150 m2/person.
Therefore systematic utilization of agricultural waste and
byproducts of animal food production can contribute some
amount of biomass. However, to supply the remaining
present biomass need is physically not feasible, as it
requires additional 4000 m2/person of biologically
productive land, which is not available on Planet Earth.
There are other reasons that prevent the large scale
use of biomass. Energy farming is in direct competition
with food production for land, for water, and for fertilizer.
It is no secret that humankind is already struggling to
eliminate hunger; therefore, to take land, water, and
fertilizers away from food production is, in a global
perspective, not an option. Furthermore, specific plant
farming for biomolecules is an enemy of biodiversity. Any
land taken away from wilderness destroys habitat and
contributes to the mass extinction of species. However, this
will inevitably happen with increasing use of biomass. It is
quite obvious that a healthy World ecosystem cannot spare
sufficient biomass production capacity to feed the
equivalent of 156 Billion human beings.
Complicated Structures of Bioactive Compounds
Some bioactive compounds from natural products have
complicated structures that preclude economical industrial
syntheses. This therefore implies that the acquisition of
such products relies on massive collection efforts, a process
which is time consuming and ultimately damaging to
biodiversity. Alternative strategies for an environmentally
friendly and economical feasible supply of natural products
are therefore needed.
Natural Products and Combinatorial Chemistry Drug companies are currently developing interests in
making products that have a larger potential profit base
than anti-infectious drugs. These include compounds that
provide social benefits, that reduce the symptoms of
allergies and arthritis, or that can soothe the stomach. It
therefore appears that this loss of interest can be attributed
to the enormous effort and expense that is required to pick
and choose a biological source and then to isolate active
natural products, decipher their structures, and begin the
long road to product development. It is also apparent that
combinatorial chemistry and other synthetic chemistries
revolving around certain basic chemical structures are now
serving as a never-ending source of products to feed the
screening robots of the drug industry. Within many large
pharmaceutical companies, progress of professionals is
primarily based upon numbers of compounds that can be
produced and sent to the screening machines. This tends to
work against the numerous steps needed even to find one
compound in natural-product discovery. It is important to
realize that the primary purpose of combinatorial chemistry
should be to complement and assist the efforts of natural-
product drug discovery and development, not to supersede
it (Demain, 1981).
Combinatorial chemistry generates larger libraries
but the compounds therein are relatively simple planar
molecules contrary to the natural products' pool that gives a
much higher hit-rate in high throughput screening with high
chemical diversity. Further, improvements in isolation,
purification and characterisation procedures have fastened
the output of natural product research, thereby reviving the
interest of the pharmaceutical industry.
Interdisciplinary collaboration in Natural Product
Research
Natural products chemistry increasingly collaborates with
synthetic chemistry, and vice versa, which works to the
strengths of both fields. Therefore, an integrated approach
that combines the various discovery tools and the new
discipline of integrative biology will provide the key for
success in natural product drug discovery and development.
The pharmaceutical industry has to come forward in
utilising the knowledge available in traditional medicines.
Traditional medicines may provide cure for different types
of diseases and disorders but need scientific validation. In
order to focus the research on traditional medicines to serve
national interests, the first priority is to assess the
therapeutic quality of herbal medicines objectively since
the dividing line between the modern therapies and
traditional therapies remains imprecise. In a paradigm shift
from discovery of single bioactive molecules, multi-
constituent mainstay of bioactive extracts can be
27 International Journal of Natural Products Research 2014; 4(1): 19-32
emphasised for synergistic and antagonistic studies at
cellular and molecular levels.
Networking and Natural Products Research
Advancement
Most natural products chemists in Africa, as is indeed the
case with Scientists in other fields are often forced to work
with inadequate facilities, both in terms of appropriate
infrastructure and modern equipment. These problems
coupled with lack of full access to the scientific literature
and inadequate financial resources pose as serious
stumbling blocks to the development of natural products
research in Africa. The establishment of networks with the
aim of initiating, developing and promoting research in
natural products could be one way of accelerating the
development of this science both at the local and
international levels. The networks may aim at not building
infrastructure but towards strengthening capabilities
through local and international cooperation. This
cooperation may be enhanced through information
dissemination and exchange of ideas, effected by means of
publications, workshops, symposia, exchange visits and
fellowship schemes.
Sources for Natural Products
Tropical plants were initially the focus of natural product
searches. However, the probability of discovering new
useful compounds from terrestrial microorganisms is
comparatively low. Hence it is worthwhile to explore the
possibilities of deriving not only new and novel antibiotics
and pharmaceutically important products but also other
economically valuable products such as novel enzymes,
fine chemicals, and vitamins. Now, the newest area to study
is the rich population of microorganisms from extreme
environments, especially bacteria and fungi. And while
human impact has destroyed much of the plant and animal
ecosystems, humanity has actually created novel habitats
for many microorganisms.
Microorganisms hold other advantages as well.
From a maintenance perspective, they are easier to store
and work with in a laboratory. From a molecular biology
perspective, they are even more advantageous because their
genes responsible for the synthesis of constituent active
compounds are located together in clusters. Scientists also
are exploring the possibility of inserting clusters of foreign
genes involved in the synthesis of plant and animal natural
products into bacteria, thus enabling the synthesis of useful
molecules readily in the lab. So it is possible to identify
which genes are involved in producing which compound.
This capability would ease the cost of acquiring raw
materials and protecting habitats. In essence, the bacteria
are doing the work of the combinatorial chemistry.
Low concentration of Bioactive compounds in
Organisms
The low concentration of bioactive substances in producing
organisms or the limited quantity of the organism itself or
the geographic, sexual and seasonal variations in the
amounts and in the nature of the produced secondary
metabolites seriously affects research on natural products.
This therefore means that natural products research can
threaten biodiversity. Thus considering bioethical
perspectives and finding alternative solutions to the
problems of supply for bioactive substances should be
given high priority in natural product research and
development. This is because impacts from stress on
natural products producing organisms although manifested
at individual species level are magnified in effect
throughout the entire ecosystem because of complex
interconnected relationships between species at different
trophic levels, including interactions such as predation,
competition and mutualism.
Complicated Structures of Bioactive Compounds
Some bioactive compounds from natural products have
complicated structures that preclude economical industrial
syntheses. This therefore implies that the acquisition of
such products relies on massive collection efforts, a process
which is time consuming and ultimately damaging to
biodiversity. Alternative strategies for an environmentally
friendly and economical feasible supply of natural products
are therefore needed.
OPPORTUNITIES IN NATURAL PRODUCT
DEVELOPMENT
Pharmaceuticals
Medicinal properties of biomolecules are based on the
antioxidant, antimicrobial, antitumour, anti-inflammatory,
insecticides and nematocides, herbicides, hormones,
antipyretic effects as well as its ability to the control of
toxic blooms by its phytochemicals. These phytochemicals
either act on different systems of animals including man,
and/or act through interfering in the metabolism of
microbes infecting them. phytochemicals derived from
them are also extremely useful as lead structures for
synthetic modification and optimization of bioactivity. The
microbes may be pathogenic or symbiotic. In either way the
bioactive compounds from microalgae play a determining
role in regulating host-microbe interaction in favour of the
host.
Dyes and colourants from natural sources for human food
are gaining importance mainly due to health issues.
Photosynthetic pigments are chlorophylls, carotenoids
(carotenes and xanthophylls) and phycobilins.
Functional food ingredients are substances derived from
plants or animals which besides nutritious effects, have one
or more functions for the human organism such as
improving the state of health or well-being or reducing the
risk of diseases (Diplock et al., 1999). Besides, these
ingredients have series of additional characteristics as, for
instance, the need for effectiveness in their beneficial
action at the normal consumed doses. Functional bioactive
materials include peptides, amino acids, selenium, taurine,
polysaccharides, polyphenolics, hydrolysates, antioxidants,
enzymes and alkaloids as well as micronutrients such as
omega-3 fatty acids, linoleic acids, phytosterols, soluble
fibre (inulin and fructooligosaccharides, called prebiotics).
Functional ingredients are used in cosmetics, pet food,
animal feeds, dietary supplements, bioactive packaging and
a range of other industrial products. Sources offering high
potential include bacteria, seaweed, finfish and microalgae.
Cosmeceuticals include an array of compounds commonly
found in modern foods to smooth, moisturize, protect and
heal skin. These compounds promote skin regeneration and
produce antioxidants and oils for anti-aging formulations
28 International Journal of Natural Products Research 2014; 4(1): 19-32
MOLECULAR FARMING
The idea of molecular farming (also called molecular
pharming, biopharming or gene pharming) to generate
biomolecules (Pharmaceuticals, Functional proteins and
Industrial enzymes) valuable to industry that are difficult
or even impossible to produce in another way, or which
require prohibitively high production costs in other
systems. Successful expression and assembly of a
recombinant human monoclonal IgA antibody has already
been demonstrated for Chlamydomonas reinhardtii
(Mayfield et al., 2003), while stable expression of the
hepatitis B surface antigen gene has been shown in
Dunaliella salina (Sayre et al., 2001; Geng et al., 2003;
Sun et al., 2003). In this way, antibody and vaccine
production can become not only much more convenient,
but also much cheaper than expression in other systems.
Expression in an organism without an immune system
allows expression of antibodies that would otherwise
interfere with the immune system of the host animal used in
conventional antibody production. Since Dunaliella is
otherwise used for nutrition, there is no need for
purification of the antigen, so the intact algae could be used
to deliver a vaccine. Microalgae have also been shown to
be useful for expressing insecticidal proteins. Because the
green alga Chlorella is one possible food for mosquito
larvae, the mosquito hormone trypsin-modulating oostatic
factor (TMOF) was heterologously expressed in Chlorella.
TMOF causes termination of trypsin biosynthesis in the
mosquito gut. After feeding mosquito larvae with these
recombinant Chlorella cells the larvae died within 72 h
(Borovsky, 2003). Because diseases such as malaria,
dengue and west Nile fever are transmitted via mosquitoes,
mosquito abatement is an expensive requirement in tropical
countries. Use of such transgenic algae might be a much
cheaper alternative. The utilization of algae as an
expression system is not restricted to antibodies, antigens,
or insecticidal proteins.
APPLICATIONS OF STARCH
Starch is one of the most widely used ingredients in the
food industry. There is a limitation on native starch for
special uses. Native starch cannot withstand the typical
Industrial processing conditions such as extreme
temperature, pH, high shear rate, and freeze thaw variation
encountered during processing. Therefore there is the need
for modification. The principal biochemical components of
starch are amylose and amylopectin, and these have been
pioneer target for modification. Modification had been
accomplished using chemical action, physical and genetic
modifications. The variations associated with different
starch sources may lead to differences in terms of
formation, development or derivation of new products with
wider industrial applications.
Partially refined and treated starches can be used
to modifying texture of gum, pastilles and jellies. Some
other specialty starches have been tailored to impact neutral
taste, and low viscosity in products like salad, creams, and
mayonnaises. Native starches can be modified in order to
form granular cold water gel or viscous mass on addition of
water even at room temperature (28°C). Such value added
starch that thickens without the applications of heat, find
applications in preparation of food products such as instant
puddings and cold dessert mixes. Specialty starches of
amiable attributes include, heat stability and resistance to
change in pH. These qualities make starch a functional raw
material for products like baby meal, pudding and sauce for
canning fruits.
Natural Management of Physiological Disorder
With regard to rate and extent of digestibility or nutrition,
starch can be group into three classes namely, rapidly
digestible starch, slowly digestible starch and resistant
starch (Englyst et al., 1992). Slowly digestible starches are
important for treatment and prevention of some glucose
dependent diseases. Elevated plasma glucose and insulin
levels after a glucose load are associated with non-insulin
dependent diabetes (Krapt and Nosal, 1975) and
cardiovascular diseases (Flodin, 1986). Prolonged digestion
and absorption of carbohydrates are favourable for the
dietary management of metabolic disorders such as
diabetes and hyperlipidemia (Asp, 1994; Wursch, 1994). In
addition, starch plays an important role as a component of
carbohydrate-based fat replacers, one of the strategies to
manage influential disease of hypercholestromia. Stable
starch-lipid composite can be prepared by co-jet cooking
starch, lipid and water in excess steam. The products are
useful in preparation of ice-cream and chocolate chip
cookies. Consequently, slowly digestible starch and dietary
fibres are gaining recognition as a component in
formulation of a functional cereal and meat products (Goff
et al., 2001).
Pectic substances, cellulose, hemicellulose and
lignin are the major components of the plant cell wall that
are collectively referred to as dietary fibre. Pectic
substances have important physiological and nutritional
effects such as hypocholesterolemic effect, increased
excretion of faecal sterols and lipids. Others are binding of
bile salts and polyvalent cations. Similarly, it is also now
well established that the main physiological effects of
dietary fiber are improved bowel function and improved
carbohydrate and lipid metabolism (Kay and Truswell,
1977). Dietary fiber can be used in the treatment of/or
counteracting obesity, diabetes, hyperlipidemia, colon
disease and constipation (Takahashi et al. 1999).
Starch Sugar and Chemicals
Starch sugar can be obtained from the action of dilute acid
on starch. It is a very important raw material in brewing
industry and spirituous liquors. Other sweetening agents
that can be produced from starch include D-glucose and
maltose. The sweetener is excellent because, the products
are not associated with all the physiological abnormalities
identified with consumption of cane sucrose. Therefore, the
product is a delight in confectionery (Radley, 1976). Heavy
chemicals such as ethanol, butanol, acetone, glycerol and
other organic chemicals notably acetic, citric, itaconic,
gluconic and lactic acids can be produced from starchy
materials using fermentation processes. Fermentation
process utilizing starch based substrates can be used to
produce complex organic chemicals that may not be easily
synthesized through chemical pathways. Some of the
organic chemicals include antibiotics, amino acids,
vitamins notably riboflavin, cobamides, carotene and
29 International Journal of Natural Products Research 2014; 4(1): 19-32
enzymes.
Biopolymer Based Packing Materials
Low cost, availability and total degradability after usage
has made starch a candidate material for replacement of
petroleum-derived synthetic polymers to decrease
environmental pollution. Some of the desirable attributes of
edible films are: renewable nature of their components,
among which starch is chief. Its films have ability to
function as carriers of food additives (e.g. flavourants,
antioxidants) and as selection barrier to transport vapours
and gases in living foods (George et al., 1995). Starch
derivatives can also be tailored for paper Industries. The
derivatives can function as wet end additives, surface sizes,
coatings and binders (Gebre-Mariam, 1996).
Vehicle for Bio-Active Components
Starch has been used as a carrier of active components in
drugs and fertilizer. The technique ensures that the active
components are released at the target over a period of time
at a controlled rate (Chen and Jane, 1995). The active
agents released at a controlled rate provide a continual but
constant concentration that exerts a steady action during
period of release. This prevents the loss of active agents by
degradation, leaching, evaporation or surface-run-off
(Boydston, 1992; FIeming et al., 1992). Similarly,
pesticides can be encapsulated within starch solid matrices
with view to control rate of release, decomposition,
leaching, ground water contamination, dermatoxicity and
other uncertainties associated with application of
therapeutic active agents (Carr et al., 1991; Schreiber and
Shasha, 1988).
Non-Food Applications of Modified Starch
Modified starch also finds utilization in oil-well drilling
muds, cosmetics formulation (hair dressings, wave sets,
etc.), production of plastics and resins, building materials
(wall boards and acoustic tiles), photography (coat for
fibres and plates), and manufacture of soapy and soapless
detergents. Treated starch conjugated to nitrates is
prominent component of some explosives. Dialdehyde
starch is water-resistant with high binding capacity which
makes them valuable as adhesive and binders. The bonding
characteristics of starch can be harnessed for manufacture
of briquettes. Briquettes have less carbon content than
petroleum products and therefore its burnt products will
contain lesser pollutants (tar, carbon monoxide, nitrogen
monoxide).
Valuable By-Product from Fermentation of Starchy
Foods
Organic acids are examples of such valuable by-product of
the fermentation of high carbohydrate containing industrial
substrates. Lactic acid, an intermediate-volume especially
chemical is under increasing demand in Food,
Pharmaceutical and Chemical Industries and for production
of Poly lactic acid polymers, which possess excellent
biomedical applications. Lactic acid is currently
manufactured either through chemical or microbial route
via fermentative mode. Wastes containing starch generated
from food processing plants may be regarded as a viable
option for meeting this growing demand for lactic acid, if
appropriate biotechnological interventions are used.
Blends Research: Bio-artificial Polymers and Bio-
polymeric Materials
This represents a new class of polymeric materials based on
blends of synthetic and natural polymers, de-signed with
the purpose of producing new materials with enhanced
properties with respect to the single components. Synthetic
components could be poly(vinyl alcohol) PVA;
poly(acrylic acid) PAA, poly(methacrylic acid) PMAA
among others while collagen, gelatin, starch, hyaluronic
acid (HA) and dextrin are examples of biological
components. These components can be mixed together in
various proportions and various properties including
mechanical, electronic, optical, dielectric etc. can be
measured. They are often prepared in the form of films and
generally regarded as soft solids.
Natural Fibre Reinforced Composites Research
Natural fibers are abundantly available as renewable
resource, low-cost, biodegradable and environmentally
friendly. They are also useful as fillers in polymers as they
can increase electrical resistance, thermal and acoustic
insulation. Renewable cellulose fibers include wood flour,
sisal, bagasse, kenaf, jute, and waste newspaper which can
be used as bio-fibers in thermoplastic composites. A
systematic development of composite materials based on
local resources for application in housing and building
sector is therefore imperative.
Self-Reinforcing Polymers and Composites
The availability of SPECTRA (a PE-based fiber) and Ultra-
High Molecular Weight Polyethylene (UHMWPE) which
are ultra-high strength and modulus fiber have introduced a
new opportunity for composite assembly. They have
applications in defence and medicine.
ALTERNATIVE PROTEIN SOURCE FOR ORGANIC
AQUACULTURE
As the global population continues to grow, sources for
highly nutritious, safe, healthy and high protein content
feeds will be in extremely high demand to feed the
burgeoning population. Seafood and aquatic products
remain one of the premier protein sources in the world
today. However, captive fisheries cannot provide and
sustain this protein source for the growing global
population. This represents a tremendous opportunity for
aquaculture and its associated industries. However, the
aquaculture business must undergo tremendous changes in
order to be positioned to fill the huge gap between supply
and demand for seafood products. One of the most daunting
challenges facing aquaculture is the identification,
utilization and sustainability of alternate protein and lipid
sources – a challenge that must be met if the industry is to
survive and flourish.
RESEARCH PRIORITY
As land-based sources run dry, there is needed to go to the
ends of the aquatics to acquire the resources needed to
stoke industrial growth. The aquatic environment support
unique ecosystems of animals and microbes. The microbes
are sources of enzymes used in DNA fingerprinting, in
detergents, to enhance the flow of oil from old wells, and to
produce bioactive compounds that could prove effective
against cancer or other diseases. As chemically interesting
and bio- logically significant secondary metabolites, marine
30 International Journal of Natural Products Research 2014; 4(1): 19-32
microorganisms are expected to serve as lead compounds
for potential drug development or pharmacological tools
for basic research in life sciences. The metabolic and
physiological capabilities of marine microorganisms that
allow them to survive on their unique habitats also provide
a great potential for production of metabolites, which are
not found in terrestrial environments.
The biota of marine microorganisms has
developed unique metabolic and physiological functions
that not only ensure survival in extreme habitats but also
offer a potential for the production of novel enzymes and
bioactive metabolites for potential exploitation. It is
estimated that less than 5% of the bacteria observed by
microscopy are culturable under standard laboratory
conditions. Out of the large number of species examined,
only a fraction of marine bacteria have been isolated and
cultured.
Most marine microorganisms are of the gram-
negative eubacteria, cyanobacteria, and the myxobacteria
groups, which are generally thought to produce many
medically useful substances.
Several well-known chemists and biologists
reviewed different aspects of marine natural products. The
majority of natural products derived from microorganisms,
plants, and animals could exhibit a wide range of activities.
They are useful to produce important antibiotic, anti-
inflammatory, antitumor, antiviral, insecticidal, and
herbicidal effects. Marine toxins, enzymes, and other
chemicals are also important. A relatively large number of
marine organisms are known to produce secondary
metabolites that possess antibiotic properties, including
blue-green, green, brown, and red algae, dinoflagellates,
sponges, jellyfish, sea anemones, and others apart from
microorganisms. However, little research has been done on
this group of organisms.
Biotechnological prospecting of the marine
environment for microorganisms is still in its infant stage.
Several microorganisms are of considerable current interest
as a new promising source of metabolites and enzymes
with unsuspected application potential. There is ample
scope for the selection of microorganisms to produce novel
enzymes. There is the possibility of producing future drugs
from several marine organisms like algae, sponges,
jellyfish, corals, shark cartilage and shellfish, oyster, yeast,
and fungi
Specific policies to keep the nation's natural
resources available over very long-term should be a high
priority.
The need for linkages and alliances
In harnessing biodiversity and the sectors linked to
biodiversity, there is need for greater investment in policy-
relevant science and in strengthening the ability of
institutions to act coherently and in partnership. Experience
has shown that science that isolates problems and ignores
contexts of scale issues does not necessarily produce
sustainable solutions. Good science takes a holistic
approach including paying serious attention to socio-
economic aspects. It is necessary to promote
interdisciplinary science to strengthen government policies
and support bilateral, regional and international
negotiations and cooperation and the development of
market instruments and indicators. Conservation and
sustainable utilization of biological resources cannot be
achieved when there is such a gap in knowledge of existing
biodiversity and its related potential.
Nigeria has significant expertise in natural
products discovery, microbiology and molecular biology,
chemistry and engineering. Therefore developing strategic
research partnerships with industry through the formation
of public-private partnerships would represent a good way
to take forward research capacity towards commercial
targets with steer from industry of emerging market
opportunities. Supporting this emerging market sector will
help ensure the strong science-base and industry capacity in
Nigeria is maintained to establish a competitive position in
the emerging bio-economy.
As global trends of biodiversity continue to show
a decline, scientists in the ACP countries including
taxonomists, chemists, biochemists, pharmacologists, and
biologists in various disciplines such as evolution and
ecology, have the responsibility of increasing collaboration
not only among the scientists themselves but with local
communities to explore, collect, characterize and preserve
biodiversity. Capacity building to address the weak science
base should be given priority especially in building human
resource capacity and infrastructure including research
facilities and legislative framework. Biodiversity
conservation and sustainable use for social and economic
development should be based on local biodiversity
management systems of rural communities and indigenous
peoples buttressed by sound technical advice from their
scientific and legal experts.
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Source of support: Nil; Conflict of interest: None declared