eChapters

Introduction

Solanum trilobatum L., an important medicinal plant, belonging to Solanaceae is widely distributed in South Asia and has been used in Indian traditional medicinal systems of Siddha and Ayurveda. The members of Solanaceae accumulate steroidal alkaloids based on a C₂₇ cholestane skeleton, e.g. solasodine and tomatidine. Recently, mixtures of solasodine glycosides have been successfully used for the treatment of certain human skin carcinomas (Cham, 1994). Solasodine glycosides have antineoplastic activity in cell culture, animals and in humans (Cham and Daunter1990). It has been demonstrated that specific endogenous lectins which are present on the plasma membranes of susceptible cells recognize and bind the sugar moiety of the solasodine glycosides and the glycosides are subsequently internalized and cause cell death (Cham and Daunter1990). Hence the present study was undertaken to isolate the solasodine from S. trilobatum.

ABSTRACT

An efficient and reliable micropropagation and mycorrhization techniques were established for a medicinal plant Solanum trilobatum L., using internodal explant. Callus formation occurred from both the cut ends of explants cultured on MS medium supplemented with 2,4-D (3.0 mg/l). Direct shoot and multiple shoot formation were noticed from the proximal cut end of explants on BA (2.0 mg/l) alone and BA (2.0 mg/ l) + NAA (0.5 mg/l). Root formation was directly induced from the basal cut end of explants cultured on IBA (1.0 mg/l). In vitro plantlet regeneration has been achieved on BA (2.0 mg/l) + IBA (1.0 mg/l). After 4 weeks, well-developed in vitro plantlets were hardened in plastic cups filled with sterile soil and vermiculite (3:1). During acclimatization, sterile Arbuscular Mycorrhizal (AM) fungal spores were added for enhance the survivability of in vitro plants in the field condition. The level of biochemical changes and increased survivability were studied in 10 weeks old plants inoculated with spores of Glomus mosseae and Gigaspora margarita.

ABSTRACT

A rapid micropropagation technique have been established for Solanum trilobatum L., a medicinal plant from internodal explant. Callus formation was observed from both cut ends of explants cultured on MS medium supplemented with 2,4-D (3.0 mg/l). Direct shoot and multiple shoot formation were noticed from explants (proximal cut end) on BAP (2.0 mg/l) alone and BAP (2.0 mg/l) + NAA (0.5 mg/l). Root formation was directly produced from the basal cut end of explants cultured on IBA (1.0 mg/l). In vitro plantlet regeneration has been achieved on BAP (2.0 mg/l) + IBA (1.0 mg/l). Regenerated plants were transferred to sterile vermiculite and soil mixture (3:1). In vitro propagated plants were grew successfully under the field conditions. In vitro propagation can be a useful tool for the conservation of this medicinal species.

ABSTRACT

Advances in biotechnology, particularly methods for culturing plant cells and tissues can provide new means for the commercial processing of even rare plants and th chemicals they produce. These new technologies will extend and enhance the usefulness of plants as renewable resources of valuable chemicals. Aristolochic acid is mainly found in the genus Aristolochia. Aristolochic acid has been shown to hav anti-tumour activity and has been recommended for its activity against various effect of snakebite and its capacity to inhibit phospholipase A2 or other enzymes Considering the importance of medicinal use of A. bracteolata and A. indica, in th present study, they were selected for in vitro development and rapid multiplication o plant through tissue culture. The study was undertaken to enhance the in vitr production of Aristolochic acid in different tissue cultures. Cell suspension culture was established from friable calli of both the species in M liquid medium. Bergmann plating technique was carried out for cell line selection fo more production of Aristolochic acid. Primary transformation was carried out by Agrobacterium tumefaciens strain LBA4404 / pTOK233 with Gus and hpt genes to confirm the transgenic potential of A. bracteolata and A. indica. In order to enhance the productio of aristolochic acid in in vitro culture condition, the physical, chemical and biologica conditions were altered. Aristolochic acid was isolated, identified and purified from naturally growing plants as well as from tissue culture plants and all other cultur stages.

ABSTRACT

Advances in biotechnology, particularly methods for culturing plant cells and tissues, can provide new means for the commercial processing of even rare plants and the chemicals they produce. These new technologies will extend and enhance the usefulness of plants as renewable resources of valuable chemicals. Aristolochic acid is mainly found in the genus Aristolochia. Aristolochic acid has been shown to have anti-tumour activity and has been recommended for its activity against various effects of snakebite and its capacity to inhibit phospholipase A₂ or other enzymes. Considering the importance of medicinal use of A. bracteolata and A. indica, in the present study, they were selected for in vitro development and rapid multiplication of plant through tissue culture. The study was undertaken to enhance the in vitro production of Aristolochic acid in different tissue cultures. Cell suspension culture was established from friable calli of both the species in MS liquid medium. Bergmann plating technique was carried out for cell line selection for more production of Aristolochic acid. Primary transformation was carried out by Agrobacterium tumefaciens strain LBA4404 / pTOK233 with Gus and hpt genes to confirm the transgenic potential of A. bracteolata and A. indica. In order to enhance the production of aristolochic acid in in vitro culture condition, the physical, chemical and biological conditions were altered. Aristolochic acid was isolated, identified and purified from naturally growing plants as well as from tissue culture plants and all other culture staes

ABSTRACT

According to WHO report, over 80% of the world population relies on traditional medicine, largely plant based for their primary healthcare needs. India has 15 Agroclimatic zones, 12 ecoregions and 47,000-plant sp. and is one of the 12-mega biodiversity centres. The Indian Systems of Medicine have identified 1500 medicinal plants, of which 500 species are used in the preparation of commercial drugs. These medicinal plants contribute to 80% of the raw materials used in the preparation of drugs.

1. Introduction

The heritage of medicinal plants used in India has an ancient history. The epic of Ramayana witnessed Sanjivani Booti as life saving drug. Two important compendia on medicinal plants i.e., Charaka Samhita and Sushruta Samhita were published between 1000 BC and 600 BC. In these Ayurvedic literatures, uses of more than 1,200 plant drugs along with their action and specific therapeutic applications are mentioned. Charaka made 50 vargas (groups) of drugs while Sushruta made 38 ganas (groups) of drugs (Singh and Gautam, 1997). India, with its diverse agro-climate, harbors large plant-diversity. Eastern Himalayas comprising Darjeeling, Sikkim and adjacent Nepal as well as Bhutan hills are very rich in florastic diversity, several of which are endangered but economically useful medicinal plants with high demand in national as well as in international market (Manandhar, 1999). A great many of these wild Himalayan medicinal plants have found their way into modern bio-pharmaceuticals and bio-cosmetics in recent times (Rai et. al., 2000). One such species is Nepalese Kutki (Picrorhiza scrophulariiflora, Pennell) belongs to family Scrophulariaceae.

P. scrophulariiflora is better known by the name Nepali Kutki. The rhizome of this plant has been found to contain the chemicals like Kutkin, D-mannitol and vanillic acid (Yang, 1996). It is said to have effects on fever, malnutrition due to digestive disturbance, jaundice, diarrhoea and dysentery (Zhang et al., 1994). In India it is valued for their demonstrated value as an antibiotic. They are also used as an adulterant of, or as substitute for, Gentiana kurrooa. Properties that these two species share include the ability to stimulate appetite and gastric secretions (Jain, 1968). In Nepal rhizome of this species is also used as a cathartic, in case of dyspepsia, as a purgative as well as in the treatment of scorpion bites (Anon., 1993). Some of the important active photochemicals are listed in Table 1.

ABSTRACT

Three medicinal plants namely, Eryngium foetidum (Apiaceae), Centella asiatic (Apiaceae) and Hemidesmus indicus (Asclepiadaceae) were collected from Similipa Biosphere Reserve forest and used in this investigation. Ethanolic, methanolic chloroform and aqueous extracts of different parts like leaf, root and stem were prepare through standard techniques and screened for their anticandidal potencies agains Candida albicans, C. tropicalis and C. krusei. Anticandidal activity of the extracts wer tested using preliminary and secondary screening methods, like disc diffusion metho (DDM) & agar-cup-plate-method (ACPM) and poisoned food technique (PFT respectively. On an average the inhibitory tendency of the extracts can be arranged as ethanolic extracts > methanolic extacts > chloroform extracts > aqueous extracts Maximum degree of inhibition was observed against C. krusei. Among the plant Hemidesmus indicus showed better anticandidal activities in comparison to other tw plants tested.

ABSTRACT

Biodiversity is a major resource for drug development. Since ancient times mankind has exploited nature for all kind of useful products and enjoyed the colors, flavors and fragrances of flowers and leaves etc. The current global resurgence in the use of plant based drugs offers an ideal opportunity for the country to emerge as a major player in the herbal products market. Herbal medicines are chemically diverse and may contain thousands of bioactive compounds, which can be of immense value to the pharmaceutical industries. Since ages, herbal medicine has been a major part of traditional knowledge play an important role for identification of biological resources worthy of commercial exploitation. Origanum vulgare L. is a wild plant of Labiatae family grows widely in Ladakh region (11500 to 13000 ft). The local people of this region use this plant for various ailment and culinary purposes due to the potential of active ingredients. The present objective of this study is to isolate the thymol content, a major ingredient of O. vulgare and quantifying the same. The volatile oils were extracted through hydro-distillation and active compound was analyzed by Gas Chromatography (GC-17A Shimadzu). Our results demonstrate that the thymol content of O. vulgare from this region is 80.28% as compared to plants grown at other low altitude regions. It is well known that plants under stress respond with biosynthesis of phytochemicals to enable them to adapt to the harsh environmental conditions. Ladakh being unique in many aspects due to its geo-climatic conditions like high elevation, extreme cold, dry weather and low humidity. Plants surviving in Ladakh therefore have unique chemical composition as compared to those grown elsewhere.

ABSTRACT

The present study was designed to evaluate the effect of α-mangostin on cardiac markers against isoproterenol-induced myocardial infarction in rats. Induction of rats with Isoproterenol (150 mg/kg body wt, i.p) for 2 days resulted in a marked reduction in the activities of cardiac tissue marker enzymes (LDH, CPK, GOT and GPT). Pretreatment with α-mangostin (200 mg/kg of body wt/day) orally for 6 days significantly prevented these alterations and restored the enzyme activities to near normal levels. In conclusion, these findings demonstrate the protective effect of α-mangostin on isoproterenol induced experimental myocardial infarction in rats.

ABSTRACT

The Kolanthamamalai hill an offshoot of Kalakadu Mundanthurai Tiger Reserve of Southern Western Ghats is one of the important forest reserves of Tirunelveli District. The physiography of this range differs much from the adjacent portions of Southern Western Ghats of Tamil Nadu state due to its discontinuity, varying altitude, ridges and their height and breadth. The altitude of the hilly rugged terrain ranges from 150 to 300m, with the highest peak being Kolanthamamalai. Field visits were made in the study area to survey and to gather information on medicinal flora. The vegetation of Kolanthamamalai hill is a mixed dry deciduous type characteristic of the high and low altitude of the mountains respectively. Lowland vegetation girdles the base of the mountain on the eastern and southern side of the hills. Along the foot hills vegetation is an open scrub with occasional trees. The low-lying areas and the seasonal watercourses are densely vegetated. The natural barriers, habitat diversity, climate and moderate rainfall have resulted in the development of unique plant diversity.

ABSTRACT

A low molecular weight antifungal protein has been purified from the leaves of a medicinal herb, Mentha viridis, L. using a combination of cold acetone precipitation, carboxymethyl cellulose column, Q-sepharose column chromatography, and preparatory native PAGE techniques. The purified protein migrated as a single band on SDS-PAGE, with a molecular weight of ca 15.5 kDa. The purified leaf protein of M. viridis inhibited mycelial growth of phytopathogens such as Fusarium solani, Fusarium sp., and Pythium aphanidermatum. The purified protein from the leaves of M. viridis inhibited the growth of human pathogens such as Candida albicans and C. tropicalis (75 mg/mL). This inhibition is concentration dependent. The purified antifungal protein of leaves of M. viridis did not show protease, chitinase, and b-1, 3 glucanase activity.

ABSTRACT

The present communication thr ows light on 118 species of flowering plants (Angiosperms) found in Dewghat forest (in Koraon forest range of Uttar Pradesh), which are traditionally used by the “Kol” tribal community and some other forest dwelling people, viz. Belbans, Bahelia, Mushahar etc. An enumeration of these plants materials is prepared with their botanical names, local / vernacular names, family names and using practices provided in this paper. This is the first ever report from the area under study on this aspect. In case of Anogeissus latifolia the leaf juice is used poisonous insect bite, grounded flower used in chronic diseases and its fruit is used asthma. The seeds of Cleome viscosa are given orally in stomach diseases. The leaves of Cassia alata used for ringworms and skin disease. The leaves juice and seed of Euphorbia thymifolia is used as a strong purgative. It leaf juice is also used for the remedy of ringworms and other skin diseases. It is an antidote for snakebite. The present study is aimed at indexing of all medicinal flora occurring in Dewghat forest (U.P.) and their uses for the benefit of the researchers to undertake studies on the prospects and potential of commercial exploitation.

ABSTRACT

Our country is well known for developing into rich and ancient traditional system of medicines based on plants. For centuries, these ancient cultures and professional practicing on traditional system viz. Ayurveda, Unani and Siddha could remain in house hold and pass through generations to generation. India is being a developing country, of late uses bioactive natural products (secondary metabolites) using in vitro culture technology of the medicinal plant species. Recently, commercial utilization of these compounds using modern techniques is in good progress. The developed western affluent world has to now depend on these compounds mostly in drug and pharmaceutical industry in recent years. Orchids as medicinal herbs, details on plant medicinal potentialities, traditional medicinal systems viz. Ayurveda, Unani and Siddha have been described.

ABSTRACT

Albizzia lebbeck is commonly called as “vagai” in Tamil belonging to family Mimosaceae, is a large deciduous tree commonly seen throughout India. Our present aim, was to study the CNS depressant activity of Albizzia lebbeck in wistar albino rats. The bark and leaves of Albizzia lebbeck were shade dried and coarsely powdered. About 500 gm of powder was extracted using petroleum ether, chloroform and alcohol by cold maceration process. The depressant activity was accessed using actophotometer. It was claimed that in indigenous system of medicine the drug has anti-inflammatory, opthalmopathy, leucoderma, leprosy, wounds, ulcers and CNS depressant activity.

ABSTRACT

Solanum trilobatum Linn. (Solanaceae) was investigated for the induction of tumor using a soil borne bacterium, Agrobacterium tumefaciens. Explants like stem segments and nodes were infected with bacterium. Tumors were induced from nodal explants within 10 days of infection. These explants were then transferred to MS basal medium and their growth was observed to be independent of exogenous supply of phytohormones. The growth rate of transformed callus was 10-fold as compared to control. They are used as a promising source of secondary metabolites of medicinal significance.

ABSTRACT

In this study, different concentrations of acetone, alcohol, benzene and chloroform extract of Wedelia chinensis were carried out against human pathogenic bacterial and fungal strains. High frequency of anti-bacterial activity was observed on the Escherichia coli. Moderate amount of antibacterial activity was observed on Staphylococcus aureus. Highly resistant bacterium to this plant was screened through antibacterial pour plate method, which showed on the following organisms Citrobacter diversens, Serratia marcescens and Streptococcus pyogenes. The aim of this study is main evaluation of antimicrobial activity of plant. The ethanolic extracts demonstrating antibacterial and antifungal activity could result in the discovery of antibacterial and antifungal agents.

ABSTRACT

In vitro culture and cryopreservation techniques are complementary to ex situ conservation of plant genetic resources that are vegetatively propagated or having recalcitrant seeds. An in vitro germplasm conservation study has been conducted on Banana passionfruit (Passiflora mollissima), a plant used in rural medicine. Micropropagated plants survived up to 12 weeks in Murashige and Skoog medium supplemented with 0.5% sucrose. Cryopreservation experiments were carried out on the explants (apical and/or axillary buds), pre-treated with vitrification solutions, dimethyl sulphoxide (DMSO) and PVS2 (Plant vitrification solution-2) with or without desiccation treatment and frozen in liquid nitrogen (LN). The survival and regeneration of apical buds were higher than axillary buds when pre-treated with 15% DMSO. Treatment with 20 % PVS2 for 1 h followed by 100 % PVS2 for 20 min gave maximum shoot recovery (40%) from cryopreserved apical buds. Desiccation alone was not successful but combination of pre-treatment of PVS2 (20% for 1h and 100% for 20min) with 3 h desiccation gave 30% plant survival from frozen apical buds. Regenerated shoots were rooted on MS medium with 1.0 mgl-1 naphthalene acetic acid (NAA) and 0.2 % activated charcoal.

1. Introduction

Phytochemists and pharmacologists from all over the world obtain several patents for herbal drugs developed on the basis of the indigenous knowledge systems of different ethnic groups. Many countries rich in traditional medicinal knowledge have been conducting ethnobotanical survey of medicinal plants (Patil and Bhaskar, 2006). In India the native people have exploited a variety of herbal medicines for effective curing of various diseases. The plants used, preparation and administration of drug varies from area to area (Rajaram, 2006). The ethnobotanical research still plays its evident scientific role in stimulating further phytochemical and pharmacological studies (Leporatti and Corradi, 2001).

The objective of this study is to interact with Kani traditional healers and document their traditional knowledge. The Kani-tribals are one of the most primitive hill tribes of Western Ghats. They occupy the slopes of the Agasthiarmalai in Tirunelveli, Tamil Nadu, India. Some ethnobotanical studies have been done in this area (Anonymous, 1948-76, Chopara et al., 1956, Satyavati, 1976, Jain, 1981, Nagendra Prasad et al., 1996). The impact of deforestation, urbanization and modernization makes the tribals shifting from their natural habitats to urban areas. Documenting the traditional knowledge through ethnobotanical studies is important for the conservation of medicinal plants and traditional medicines.

ABSTRACT

Traditionally, the rural communities of Trivandrum have been preserving small tracts of virgin forests or small groves since time immemorial due to strong religious beliefs anointed with the groves. These forest patches are biodiversity rich communities and a large number of medicinal plants of the region are confined to these groves only. The indigenous people use the plants for medicinal as well as religious purposes. Over the years, such forests have been attributed as a treasure trove of threatened species and dispensary of medicinal plants. During the investigation, 132 medicinal plants belonging to 63 families and 119 genera were recorded from 25 miniature sacred forests of Trivandrum district. This study was based on medicinal plants used in traditional health care by local and indigenous people. About 80% local people use different parts of plants for various ailments. The present finding revealed that most of the plants are used for skin diseases, cold, cough and fever, etc. Leaves are predominantly used than the other plant parts. Important families within the groves were Apocynaceae, Papilionaceae, Urticaceae, Combretaceae and Euphorbiaceae. Presence of a large number of monospecific families indicates immediate need of a conservation measure to secure sustainable utilization of medicinal plants of sacred groves of Trivandrum district.

ABSTRACT

Free radical scavenging property and antimicrobial activity of Triphala, the herbal product made of equal proportion of Terminalia chebula, Terminalia bellerica and Emblica officinalis were evaluated. Ethanol extracts of the formulation were tested for its invitro antioxidant activity by using improved ABTS radical cation decolorizing assay and invitro antimicrobial activity against Streptococcus mutans (predominantly involved in bio-film formation) by both well-diffusion and turbidity method to determine its minimal inhibitory concentration. An effort was also made to correlate its antiplaque activity using an invitro assay (where conditions kept similar to oral cavity) with Triphala and two commercial toothpastes (Colgate and Pepsodent). The ethanol extract showed significant antimicrobial and antioxidant activity. Triphala showed effective antiplaque activity when compared with the other tooth pastes. The herbal extract effectively inhibited the bio-film formation and more antioxidant activity exhibited by the extract might protect the gum cells effectively from free radicals than the commercial toothpastes, having less antioxidant activity.

1. Introduction

India is an exquisite example of biodiversity. From time immemorial scholars like Charaka, Barathwaj, Athreyan, Agnivesha, Dhanyandhari, Shushruthan, Wakbadan and Bharathduja etc. have studied and explored the possibility of such a diversity for human welfare and the most conspicuous exploration in this field has lead to the discovery of so many indigenous medicinal plants that were scripted mainly in Vedas (1500 BC) that contain rich materials on herbal lore of that time. Charaka in his medical treatise – Charaka samhita delt with innumerable medicinal plants, their usage and descriptions. Besides the two above said texts, treatise like Sushruth samhita and Ashtangha hridaya samhita are a few among other precious ancient texts. Thus the gradual accumulation of practical and systematic medical knowledge lead to the formation of Ayurveda.

Ayurveda - the science of life, prevention and longevity, is the oldest and most holistic or comprehensive medical system available. It was placed in written form over 2000 years ago. Ayurveda is said to have been first complied as a text by Agnivesha (Agniveshtantra). This text was later revised by Charaka and renamed as Charaka samhita (completed by Dhridhabala). The concept of medicines envisaged in the Ayurveda comes from the monumental scripture called Ashtanga hridaya and Sahasrayoga.

ABSTRACT

Purine Nucleoside Phosphorylase (PNP) is an enzyme that functions in the purine salvage pathway by catalyzing the phosphorolysis of purine nucleoside thereby releasing the purine bases and phosphorylated sugar. Interest in PNP as a drug target arises from its role in T-cell proliferation and T-cell mediated autoimmune diseases. Recently, we have isolated the compound, coixol, from the plant Scoparia dulcis L. and its three-dimensional structure has been elucidated. As the structure of the coixol mimics the structure of PNP inhibitors, we have undertaken the molecular modeling studies of this compound with Human PNP, as a screening test for further in vivo studies. Generally PNP inhibitors have been synthesized with a ribose sugar moiety attached to them. As the plant Scoparia dulcis L. contains glucose and rhamnose (six membered ring), these sugar moieties are also included along with ribose in the presen study. In order to understand the binding mode and interactions of the isolated compound attached with different sugar groups, we have carried out the docking studies with Human PNP. The interactions between the ligand molecules and active site residues of Human PNP are similar to those of solved complexes and the energy values are also comparable, which clearly indicate that these ligands may act as inhibitors.

ABSTRACT

Phospholipase A₂ catalyzes the hydrolysis of glycerophospholipids at the sn-2 position and releases fatty acids and lysophospholipids. When the fatty acid is the arachidonic acid, a complementary metabolism leads to pro-inflammatory mediators such as prostaglandins, leukotrienes, thromboxanes and platelet activating factors. Thus, modulating pro-inflammatory lipid mediator production by inhibiting PLA₂ activity remains a potential target for the development of new drugs for the treatment of inflammatory diseases. Medicinal plants have been explored therapeutically in traditional medicines and are a valuable source for drug discovery. Molecular docking studies were carried out for anti-inflammatory compounds from various plant sources with human non-pancreatic secretory phospholipase A₂.

ABSTRACT

Diabetes is a chronic endocrinologic disorder characterized by high blood levels of glucose due to insufficient secretion of insulin by the pancreas or improper utilization of insulin by target cells. More than 120 million people from all over the globe are estimated to suffer from this malady. Many plants and their constituents have become chief ingredients of a number of pharmaceutical preparations used against diabetes. An intensive survey undertaken for over 4 years in the tribal belts of Orissa to identify the plants used in folk medicine and the methodologies employed by the herbal healers have revealed that 35 species are being employed to cure diabetes. Out of 313 patients (185 males and 128 females) interviewed, 211 (67.5%) use Gymnema sylvestre, Momordica charantia, Trigonella foenum-graecum, Tinospora cordifolia, Pterocarpus marsupium, Andrographis paniculata and Rauwolfia serpentina in one form or the other regularly. Multi-plant preparations gave 80% results whereas single plant administration gave less than 50% results. Polyherbal treatment is advocated as multi-pronged attack to achieve desired results.

ABSTRACT

Colchicine, one of the most widely used alkaloids is synthesized in Gloriosa species, a plant of great medicinal importance. The seeds, tubers and leaves of six different species of Gloriosa were phytochemically investigated for alkaloids and were found to contain colchicine and colchicoside. These alkaloids were isolated and quantified by HPLC analysis. This is the first report of alkaloids in Gloriosa plantii, Gloriosa lutea, and Gloriosa vuchuria. The colchicine and colchicoside content of the Gloriosa species was found to be organ dependent as there was statistically significant differences (P<0.05) between different organs but not among different species under study. The total alkaloids are organ as well as species dependent as there were statistically significant differences (P<0.05) between all the species as well as organs of different species of Gloriosa under study and its organs.

A new buzz-word is rapidly spreading through the manufacturing and analytical environment. Discussions on the application of Non Invasive Research namely the Near Infrared (NIR) Spectroscopy are often found on the agenda of production, project, and technical and even board meetings. Engineers and chemists are confronted more frequently with the challenge to decide whether a NIR instrument will be the solution to their production quality control and other analytical problems. Are there really amazing machines that can determine protein, fat, moisture, fibre, starch, nicotine, alcohol, sugar, amino acids and whatever analyses you require on any product from foodstuff to fertilizer and animal feeds in less than a minute and so simple to operate that even the unskilled labourer can handle it? In this article we will endeavor to answer the questions that often crop up in the evaluation of NIR as an analytical technique towards Natural Products.

ABSTRACT

Senna (Cassia angustifolia), a traditional medicinal crop in Tamil Nadu warrants the modern quality guidelines viz. Good Agricultural Practices (GAP) for marketing overseas. Buyers of developed countries insist on GAP and organic certification for medicinal plants. With this in view, an experiment was conducted at Medicinal Plants Unit, Botanic Garden, Tamil Nadu Agricultural University, Coimbatore to study the effect of various biostimulants on yield and yield attributing characters to standardize the biostimulant(s) for higher yield. The treatments included different concentrations of panchakavya (2% & 4%), moringa leaf extract (2 & 4%) and humic acid (0.2 & 0.4%). The field was laid out in randomized block design. Vermicompost @ 4 t ha^-1 was applied commonly to all the plots. Spraying with the above said chemicals was done at 15 days interval from 30 days after transplanting for four times. The observations were recorded for growth a yield characters and were statistically analyzed. The treatment 2% panchakavya + 2% moringa leaf extract + 0.2% humic acid recorded the highest value of growth and yield characters like plant height (44.58 cm), number of branches (6.1), number of pods (53.0), dry leaf yield (560.8 kg / acre) and dry pod yield (6. 72 g / plant).

ABSTRACT

A plant grows in a highly competitive environment. It is continually being threatened by other plants encroaching upon the space from which it draws its sustenance, by microorganisms, by insects, avian, reptilian or mammalian herbivores. In order to survive, each plant must draw upon a complex of defenses, which may be physical, such as Spines or Leathery Leaves or Chemical. These defenses are passive, coming into action only when the plant is attacked which repel insects or the herbivores that attempt to feed on them. Plants protect themselves from insect attack by providing a multitude of repellent chemicals including toxic and bitter alkaloids and tannins. Non-specialist insects and other animals that attempt to feed on the plant may be repelled, injured through severe gastrointestinal malfunction or even killed. The cabbage, spinach, mustard etc. are well known for their mustard pungent flavor that deters most animals from consuming it. Even most medicinal plants like Cynanchum collialatum of the family Asclepediaceae have tannins or alkaloids like “cardenolides” that repel most animals and insects. All these plants have a basic enzyme “Myrosinase” which react with these specific tannins to produce the toxic metabolite, which repels insects and animals. But caterpillars of few insects are known to tolerate these toxic alkaloids (ex: caterpillar of Striped Tiger Butterfly-Danaus genutia) and in turn sequester the toxic alkaloids into their tissues making themselves non-palatable to their enemies. We hypothesize the analysis of possible roles of toxic alkaloids isolated from these butterflies as bio-insecticides

1. Introduction

During the last decade, considerable attention has been focused on the involvement of oxygen free radical (OFR) in various diseases. Molecular oxygen, while providing an efficient energy from ingested food, results in free radical and peroxide by-products, which have high intrinsic toxicity. Numerous physiological processes in living organisms occasionally produce free radicals, reactive nitrogen species (RNS) and reactive oxygen species (ROS) as by-products. Their broad ranges of effects in biological systems have drawn the attention of many experimental works. ROS have been implicated in the pathophysiology of several clinical disorders, including ischemia, reperfusion injury, myocardial infarction, rheumatoid arthritis, neurodegenerative, atherosclerosis, acute hypertension, hemorrhagic shock and diabetes mellitus (Hemnani and Parihar, 1998).

Oxidative stress occurs in a cell or tissue when the concentration of reactive oxygen species (ROS) generated exceeds the antioxidant capability of the cell (Simic and Jovanovic, 1986). Although humans and other organisms possess antioxidant defense and repair systems to protect against oxidative damage, these systems are insufficient under certain conditions to prevent the damage totally (Chang and Miles, 1982). Hence, the oxygen free radicals mediated damage to protein, DNA and other biomolecules accumulates during the lifetime of organisms. Many synthetic antioxidant components exhibited toxic or mutagenic effects that have directed the attention to the naturally occurring antioxidants in recent years. A multitude of natural antioxidants have already been isolated from different plant materials such as oilseeds, cereal crops, vegetables, fruits, leaves, roots, spices and herbs (Ramarathnam et al., 1995).

Looking forward, it is clear that traditional and western medicine have the potential for rich collaboration that benefits both disciplines. There is growing interest in this partnership, as shown by the number of international journals now dedicated to such research, such as Journal of Ethnopharmacology, Complementary Therapies in Medicine, eCAM, Alternative Therapies in Health and Medicine, and the Journal of Alternative and Complementary Medicine. Even the WHO has taken note of the rich possibilities of the future of TM, having put out such documents as ‘WHO General Guidelines for Methodologies on Research and Evaluation of Traditional Medicine’ and ‘WHO Guidelines on Good Agricultural and Collection Practices (GACP) for Medicinal Plants’. Despite this enthusiasm, there are several areas where the international community will need to focus their attention if the goal of integrating botanical medicines for the good of human health is to be reached.

The traditional medicines are actually used in human for number of years and therefore its clinical existence comes as a presumption. However, for bringing more objectivity and also to confirm traditional claims, systematic clinical trials are necessary. In Ayurvedic medicine research, clinical experiences, observations or available data becomes a starting point. In conventional drug research it comes at the last. Thus, the drug discovery based on Ayurveda follows a ‘Reverse Pharmacology’ path546.

Nevertheless, all the critical Pharmacopoeial tests such as dissolution time, microbial, pesticide and heavy metals contamination etc. must be in accordance with global standards. It is important to ensure that all the Ayurvedic medicine manufacture is in accordance with Current Good Manufacturing Procedures for herbal products547,548. There have been concerns about quality standards and safety issues of herbal medicines549. The need for new regulations for botanical medicines has also been frequently stressed and some such regulations are coming in force in different parts of the world550,551.

Very few traditional systems have a fair level of documentations in place. Most of the little traditions, the flow of knowledge is mainly through word of mouth, however, the great traditions such as Ayurveda and Traditional Chinese Medicine do have a good level of documentation. For instance, Ayurveda means science of life in Sanskrit and aims at holistic management of health and disease. It remains one of the most ancient medical systems widely practiced in Indian subcontinent and has a sound philosophical, experiential and experimental basis541. Charak Samhita and Sushrut Samhita (100-500 B.C.) are main Ayurvedic classics, which describe of over 700 botanicals along with their classification, pharmacological and therapeutic properties542,543. A classic diagnostic text Madhav Nidana includes over 5000 signs and symptoms. During the course of evolution and years actual practice, the interpretation of such documents developed different schools of thoughts and resulted in wide variations in understandings. Similar situation also exists in other systems including TCM. These differences often raise issues related to authenticity and correctness of Traditional Knowledge (TK). Thus systematic documentation, interpretations and harmonization of concepts and practices remain a major challenge in most of the systems of TM. Many governments, professional and community organizations have undertaken such documentation and harmonization exercises. Projects like Traditional Medicine Knowledge Digital Library, AyuSoft, Triskandha Kosha and Medicinal Plants Database of FRLHT are attempting systematic documentation of Ayurveda in India544. Other databases such as The NAPRALERT (NAtural PRoducts ALERT) developed by Professor Norman Farnsworth contain bibliographic and factual data on natural products, including information on the pharmacology, biological activity, taxonomic distribution, ethno-medicine and chemistry of plant, microbial, and animal (including marine) extracts. Another project relates to the Global IP, Benefit Sharing and Traditional Medicine Database. It is being developed as a component of the Global Information Hub on Integrated Medicine from the work of the Commonwealth Working Group (CWG) on Traditional and Complementary Health Systems, now directed by the Malaysian Ministry of Health. This Information Hub is planning to create a network of legal centers, scholars and NGOs working together to develop a comprehensive legislative and policy review, information resource and exchange on issues pertaining to IP rights over traditional medical knowledge and the use of medicinal plants545. Other than such efforts, there is limited systematic documentation of TM knowledge and practices.

Genetics forms the basis of human life. All individuals have a physical and physiological self, determined by the interactions of genes and environment. Pharmacogenetics is the connotation used to study how heritability affects an individual’s response to drugs.494 The term ‘Pharmacogenomics’ represents systematic identification of all human genes, their products, interindividual variation and intraindividual variation in expression and function over time. It focuses on candidate genes and may include transcriptome and proteome information that affect drug metabolism, pharmacokinetics, and pharmacodynamics. It helps in predicting the patient’s response to a drug and to design new drugs495. Pharmacogenetics is study of single genes and the effects on drug response while pharmacogenomics is related to overall variation in genome. A gene is considered polymorphic when a mutation appears in more than 1% population, which may be present in the form of single nucleotide polymorphism (SNP), simple sequence length polymorphism (SSLP) and nucleotide addition or deletion. After the Human Genome Project, study in this field is accelerated dramatically. It was found that out of 1.4 million SNPs identified in the human genome, over 60,000 are present in the coding region496. These SNPs lead to miscoding of the various proteins that plays crucial role in the biological processes. If a point mutation is present in the gene coding region for various drug-metabolizing enzymes, drug target and drug transporters, it can lead to many non-therapeutic and unpredictable drug responses. In United States, over two million people suffer from severe adverse drug reactions per year and about 100,000 cases are life threatening497.

In the area of pharmaceutical discovery, screening methods continue to play a major role in drug discovery. The screening process is simply testing molecular entities (compounds/natural products) for activity to advance those that exhibit the desired activity. This process has evolved over time in both the testing methods and in the degree of testing. Originally, the screening was done entirely by dosing animals and studying their responses. Then came test tube experiments and now, testing is conducted either with cell lines or with purified proteins in miniaturized test tubes called microplate wells. Screening by microplate has allowed the degree of testing to increase from a very small selected set of compounds to libraries, which contain thousands of test substances. Technological improvements in many areas of science and information technology have led to the evolution of screening methods from time consuming, animal dosing studies to high throughput screening (HTS) methods that have the potential to generate very large datasets of information in a very short time. Today, developments in bioinformatics have opened up the possibility of virtual (in silico) screens for targets where there is sufficient knowledge of the target or of its ligand. High throughput screening has become a pivotal part of drug discovery for identifying potential lead molecules for specific disease targets. The success of screening is measured by several factors including the throughput and costs of the assays, but ultimately by how many of the HTS hits progress forward through the drug discovery pipeline. Miniaturization of assays by conversion from 96- to 384- to 1536- wells to well-less platforms, such as microarrays and the utilization of automated equipments are methodologies implemented to increase the throughput and reduce the cost of the screen.

The main purpose of herbal drug technology is to convert botanical materials into medicines with a focus on standardization and quality control with proper integration of modern scientific techniques and traditional knowledge. The use of chromatographic techniques and marker compounds to standardize botanical preparations has limitations because of their variable sources and chemical complexity. DNA-based molecular markers have utility in fields like taxonomy, physiology, embryology, genetics etc. DNA based techniques have widely been used for authentication of plant species of medicinal importance. Pharmacognosy mainly addresses the quality related issues using routine botanical and organoleptic parameters of crude drugs, and chemoprofiling assisted characterization with chromatographic and spectroscopic techniques. The new pharmacognosy includes all the aspects of drug development and discovery where the biotechnology driven applications play an important role. Current focus on chemotype-driven fingerprinting and related techniques require integration with genotype-driven molecular techniques so that an optimal characterization of botanical materials is possible. This review provides a brief account of various DNA based technologies that are useful in genotyping and quick identification of botanicals with suitable examples.

Review of Health Claims

Regulators of different countries have different procedures and views to review health claims of traditional medicine, herbal medicines, botanicals, functional foods, nutraceuticals, health products, diatory supplements and such other natural forms of materials intended to use for health promotion. However, if such products carry any therapeutic or health benefit claims then the regulators may provide general guidance and demand for sufficient evidence base in support of such claims. For instance, U. S. Food and Drug Administration, Center for Food Safety and Applied Nutrition (CFSAN) provides general guidance to review of health claims in functional foods and dietary supplements. Ethnopharmacological preparations involving herbal medicine and traditional medicines prepared from natural ingredients also will need similar process. The scientific review process for health claims of such products is comprehensive and mainly focuses on review of individual studies³²⁴

This guidance explains when a botanical drug may be marketed under an over-the-counter (OTC) drug monograph and when FDA approval of a new drug application (NDA) is needed. In addition, this document provides guidance to sponsors on submitting investigational new drug applications (INDs) for botanical drug products, including those botanical products (or botanicals) currently lawfully marketed as foods and dietary supplements in the United States. This guidance also discusses several areas in which, because of the unique nature of botanicals, FDA finds it appropriate to apply regulatory policies that differ from those applied to synthetic, semisynthetic, or otherwise highly purified or chemically modified drugs (including antibiotics). In particular, the guidance states that applicants may submit reduced documentation of preclinical safety and of chemistry, manufacturing, and controls (CMC) to support an IND for initial clinical studies of botanicals that have been legally marketed in the United States as dietary supplements or cosmetics without any known safety concerns.

The development of a new drug begins typically in the chemistry laboratory and is followed by a wide range of biological studies in vitro (cells/tissues) and in vivo (animals), which forecast what the agent would do in humans. The focus of these studies moves from evaluating the safety of a drug for use in humans to looking at its clinical relevance. Pharmacodynamics involves a set of biological studies both in vitro and and in vivo to get a better understanding of the mechanism of action of a drug. Preclinical studies mainly include safety and toxicity to ensure its safety for use in humans. Typically, preclinical in vitro, in vivo, and Phase I testing may not be necessary if preliminary data on safety are available. However, preclinical data or clinical observations are still necessary to justify a rationale for use and safety in initial clinical studies.

Three main screening approaches are generally used in drug development. Simple Screening evaluates substances that have a particular property by one or two tests. There is no need for a series of tests in which the interpretation of results of one test may depend on others. Blind Screening is used for a new plant extract where no adequate pharmacological information is available. Blind screening may give clues for potential activity and worthiness to probe further for pharmacological activities. Programmed screening involves a new plant extract or substance with known pharmacological effects and results in more precise information.

Typically herbal pharmaceutics may include any medicinal or functional food preparations such as phytopharmaceuticals, single or poly herbal formulations, and nutraceuticals made out of botanical materials. This includes two broad categories. First, there are many evidence based formulations and mixures that may or may not be based on traditional knowledge or practices. The second group includes all the traditional or ethnopharmacological preparations. Bringing herbal medications from either group to the market will require a pharmaceutics approach balanced with an understanding of the original context in which the treatment was used.

As an example, Ayurvedic medicines have been used safely for many years on a wide variety of patients. Medications that have not been altered from their original form have de facto gone through a type of safety testing. When a traditional medicine is prepared differently, then it is essential to validate the drug safety to be sure that the effects of the new procedure don’t cause harmful effects. In this same way, the value of animal testing to establish safety and toxicity is not as critical if the botanicals are used in traditional forms. Suitable animal models help in understanding the mechanism of action or pharmacodynamics of medicines. However, it is well known that no good animal models exist for many human diseases, such as asthma, diabetes, and rheumatism. The use of modern technology in making traditional preparations more contemporary and scientific is important but it should not compromise the original basis and principles described in tracditional medicine. The following examples highlight some of the concerns of this approach.

Despite its existence and continued use over many centuries, and its popularity and extensive use during the last decade, traditional medicine has not been officially recognized in most countries. Consequently, education, training and research in this area have not been accorded due attention and support. The quantity and quality of the safety and efficacy data on traditional medicine are far from sufficient to meet the criteria needed to support its use worldwide. The reasons for the lack of research data are due to not only to health care policies, but also to a lack of adequate or accepted research methodology for evaluating traditional medicine235.

The statement from General Guidelines for Methodologies on Research and Evaluation of Traditional Medicines (World Health Organization, 2000) highlights the need for consensuous in addressing the problems related to the quality of botanical drugs, which ultimately is a critical determinant of safety and efficacy of medicine. Further, the distribution and widespread sale of adulterated, misbranded, spurious botanical drug products and marked increase in misleading health claims of these products demands proper regulations on botanical medicine to protect public health236. Considering these two issues development of parameters for quality control standardization and regulatory norms for controlling the growing business of botanicals is a big task. Various regulatory authorities, research organizations and botanical drug manufacturers are constantly contributing to developing guiding principles addressing issues related to quality, safety and efficacy237. In this chapter we have highlighted problems associated with quality control of the botanicals and tried to guide a way towards a globally acceptable quality standard.

Safety is a primary concern regarding traditional and complementary therapies. There are two aspects of safety evaluations. First, to ensure that the right quality of material and apt possesses are used from sourcing to marketing; and second, there is no contamination, adulteration or spiking. Few studies have reported adulteration with steroids in some traditional Chinese dermatological preparations. In an analysis of Chinese herbal creams prescribed for dermatological conditions, Keane et al. found that eight of eleven creams analyzed contained steroids194. Spiking with corticostreoinds has been observed in some market preparations claimed to be useful in the treatment of arthritis and asthma195. Recently, Saper et al. from Harvard Medical School have reported heavy metal content of Ayurvedic herbal preparations and have recommended mandatory toxic heavy metal testing196. There have been few reports of heavy metal toxicity following traditional medicine use197,198. Such studies are important and needed, however they are more related to the quality control failures of the mass manufacturing activities. Often they are wrongly used to limit the use of TM. In reality, such a QC failure should not be considered as a general negative notion to create a bias against TM. We certainly need effective QC and regulation of herbal medicines, without limiting public access to these preparations and ensuring public interest and constituting restrictive trade practice.

Ethnopharmacology and Traditional medines use natural resources as medicines. They have developed the knowledge of this through the generations of traditions and experiences. Therefore the protection of this knowledge and protection of natural resources both remain critical. Bioprospecting involves sustainable, ethical and legal processes to access natural resources and use them judicially so that the business needs do not pose any threat to nature and to people.

One important consideration is assuring the preservation of traditional knowledge, particularly oral knowledge, within communities, for the potential benefit of others. Developing mechanisms to document traditional knowledge, such as national inventories, can be beneficial in identifying cases where conservation or cultivation is needed, based on an understanding of existing natural resources used for medicinal purposes. Decisions about access and ownership of information can also be made (including those relating to intellectual property rights, where appropriate) once methods have been found to collect and preserve traditional knowledge. On the other hand, the livelihood of traditional healers may depend on maintaining the secrecy of their healing methods - one argument for consulting with traditional healers as part of the process of planning and executing the collection, storage and testing of traditional medicines.

Extending some form of intellectual property protection to traditional knowledge, of which traditional medical knowledge is a significant part, is being actively debated in WIPO and other international forums. Existing intellectual property regimes can offer protection for purified compounds (produced by scientists and companies) isolated from a natural medicine. But traditional medicines, whose method of action may not be well understood, and which often consist of mixtures of different active substances, may not meet criteria for patentability. The principal impetus for international debate is a desire to compensate the holders of traditional knowledge appropriately for the use of their knowledge by others, or to prevent so-called “biopiracy” where knowledge or genetic materials are used without the consent of the holder. China and Kenya are examples of countries that have modified their laws in an effort to accommodate traditional medicine. It is not intended that the Commission should enter into this debate, except in so far as aspects of it may be relevant to its terms of reference, in particular stimulating innovation in traditional medicine with the purpose of expanding access to affordable medicines.

Contrary to “Law of Finite Biology” though the number of genetic codes will exhaust soon in an exponential way (presumably leading to solutions to every known genetic anomaly related health problem), the number of NCE (New Chemical Entity), their number being finite⁹⁹ too, will run out of fuel soon too, despite unraveling of genomic decoding. The bleak scenario in the pharmaceutical field is a testimony to the latter surmise. As many a wise scholar has pointed out, the era of single molecule drug seem to drawing curtains. However, unlike what seems common sense, the era of combinational drug therapies of MM paradigm probably will not foot the bill. Just as very high speed serial computing simulates parallel processing but does not make real time parallel processing, mixtures of prima facie complementary medicinal molecules will perhaps not make combinational recipes. The fundamentals of non-linear dynamical complex systems (NLDCS) paradigm demand so. The odds against success with such efforts are close to odds of success of creating life one bit at a time out of mixing C, H and O molecules in a jar would be. The number of genes might be finite, but data on their combinations (and their corresponding effects) and more so on their permutations (one has to only imagine the vastness of those possibilities) would, as of now or in near future, cause an information overload and comprehension failure¹⁰⁰ (limitation of human biological brain apparatus) pitting researchers and industry against a futility barrier. However, TM provides a silver lining to these bleak analyses. Analytical comprehension of TM recipes, regimens or techniques might be unachievable by contemporary science, empirical testing of their efficacy and safety being doable and therefore taken care of, TM can provide an outlet to the drug discovery impasse because the same natural forces that shaped multi-gene interaction into complex and dynamical mode have created some of, if not all, TM solutions.

The R&D thrust in the pharmaceutical sector is focused on development of new drugs, innovative/indigenous processes for known drugs and development of plant based drugs through investigation of leads from the traditional systems of medicine. In addition, many nutraceuticals are being consumed from unregulated markets for their perceived benefits in health care and improvement of quality of life.

Natural pharmaceuticals, nutraceuticals and cosmeceuticals are of great importance as a reservoir of chemical diversity aimed at new drug discovery and can be explored as potential antimicrobial, cardiovascular, immunosuppressive, and anticancer drugs. Around 80% of all such products are of plant origin; their sales exceeded $ 65 billion in 2003. Examples of plant products and derivatives used by the pharmaceutical industry include Paclitaxel, Vincristine, Vinblastine, Artemisinin, Camptothecin, Podophyllotoxin and such.

The nutraceutical marketplace in Europe is estimated to be $ 9 billion, while the US marketplace, estimated to be $10-12 billion in 2003, is expanding at a compounded rate of more than 20% per year. US Congress has fueled the rapid growth of nutraceuticals with the passage of the Dietary Supplement Health and Education Act (DSHEA) in 1994. Globally, there have been efforts to monitor quality and regulate the growing business of herbal drugs and traditional medicine.

Historically, the terms alternative, complementary or traditional medicine (TM) all referred to a genre of health care practices or services that got bound together as a class through the logic of reductio-ad-absurdum, or because of their “absence from the mainframe of” what has come to be known as Modern Medicine (MM). However, since Stephen Fulder¹ , the identities of TM have become more distinct, MM-TM blending more active and, the line separating the two more fuzzy. To date, the World Health Organization offers the most comprehensive definition of TM² .

WHO defines traditional medicine as including diverse health practices, approaches, knowledge and beliefs incorporating plant, animal, and/or mineral based medicines, spiritual therapies, manual techniques and exercises applied singularly or in combination to maintain well-being, as well as to treat, diagnose or prevent illness.

The phraseology MM/TM is syntactically incorrect because it is contended that medicine as such, modern or otherwise, evolves and progresses through traditions. The major difference between the various traditions of health care practices is that MM rode the crest of the high wave of reductionist-scientistic rigor of modernity³ to reach the shore of global acceptability while the others never crossed the threshold of geographical and cultural locality, remaining untested, neither proved nor disproved. Darwinian principle of survival of the fittest also endorses a truism that survival is a proof of fitness. Given this principle, it makes sense that TM as we know of it today may be useful for promoting human health. Moreover, most TM considers human beings and their health in the context of their environment. This criteria, not only defines TM apart from MM but also provides for a reason as to why lately TM is emerging out of long hibernation. Developmentally, MM isolated “human” from its global environmental context as a static, stand-alone, complete, total and delimited system in itself. While this reductionist approach has a very high pay off for the first 90% of human health problems, it fails when dynamic non-linear complex systems elements kick in (I’m not exactly sure that you mean by this phrase). TM covers some parts of those hidden variables and thats the utility to modern mankind.

To fully explore the history of medical and drug development, it would be necessary to go back as early as 13,000 BCE, where drawings on the Lascaux caves in France suggest that humans were using plants for medicinal purposes. Since then, medical traditions have evolved and dissolved across societies all over the globe. Natural products including plants, animals and minerals have been the basis of treatment of human diseases. The last two centuries have seen a focus on scientific medicine, with a focus on drugs whose effects that have been proved by the scientific method. Yet given this setting, many of the major pharmaceutical corporations have renewed their strategies in favor of natural product drug discovery. Numerous drugs have entered the international pharmacopoeia via the study of ethnopharmacology and traditional medicine. At this point in history, it is possible for both traditional and western medicine to benefit from collaboration between the two disciplines. For traditional medicines, newer guidelines of standardization, manufacture and quality control and scientifically rigorous research on the scientific basis for traditional treatments will be required. In return, traditional medical traditions can offer a more holistic approach to drug design and myriad possible targets for scientific analysis. Powerful new technologies such as automated separation techniques, high-throughput screening and combinatorial chemistry are revolutionizing drug discovery. Traditional knowledge can serve as powerful search engine, which will greatly facilitate intentional, focused and safe natural product drug discovery and help to rediscover the drug discovery process. By looking at the historical trends in drug and medical developments, it is possible to understand how current drug development will benefit from this partnership.

3.1 Tomato

Tomato (Lycopersicon esculentum) is an important vegetable crop. Its 2n= 24.

Floral biology

Flowers are borne in small forked racemose cyme. Anthesis starts at 6.30 a.m. and continues up to 11.00 a.m. Anther dehiscence is longitudinal. It occurs 1-2 days after opening of corolla. The stamen sheds its pollen when the style grows up through anther tube, thus self-pollination occurs. When the stigma protrudes above the anther tube, chances of cross pollination through bees increases. The optimum temperature for pollination is around 21°C.

TROPICAL AND SUBTROPICAL FRUITS

2.1 Mango
 

Mango is considered to be an allopolyploid. The chromosome number is 2n =40. The polyembryonic seedlings of cv. Vellaikolumban, earlier reported to be 2n= 80 was later shown to be a diploid. In Canary Island, a putative tetraploid viz Gomera-1 has been identified.

Floral biology

Flower starts opening early in the morning from 4-7 a.m. and maximum flowers open between 9.30-10.30 a.m. and complete 11 a.m. Dehiscence of anthers takes place at 11.30 a.m. and it continues up to 3.45 p.m. The pollen grains are oval, or triangular or oblong. Stigma becomes receptive even 18 hours before flower opening. Mode of pollination is entomophily; nectar is present to attract the insects.

The flowering duration is usually of short i.e. 2 to 3 weeks. The mango inflorescence or panicle bears mainly two types of flowers - male and perfect. The number of flowers per panicle varies between 1000 to 6000 depending upon the variety and climatic factors. The percentage of perfect flowers varies between 0.74 per cent in Rumani, 16.41 to 55.7 per cent in Neelum and up to 69.8 per cent in Langra.

Horticultural crops include the fruit crops, vegetables, spices, plantation crops, medicinal plants, aromatic plants, commercial flower crops and ornamental plants.

Knowledge on the methods by which these reproduce is of primary importance from the standpoint of plant breeding. Besides, their annual or perennial nature also decides the methods of breeding to be adopted to get desired improvement.

Two divisions of methods of reproduction commonly recognized are:

1. Asexual i.e. vegetative parts of the plants are utilized to produce new individuals.

2. Sexual i.e. gametic fusion, the resultant zygote develops into seed which is utilized to produce new individual.

This group can be further placed in several sub divisions according to the mode of pollination. They are

a. Naturally self pollinated crop - (e.g. tomato, pepper, brinjal) wherein cross pollination occurs less than 4 % only.

b. Often cross pollinated crop- (e.g. chillies, bhendi) wherein though self pollination is more frequent, cross- pollination may occur so frequently that some methods of preventing cross pollination between varieties and strains of different genotypic constitution must be followed throughout the breeding programme.
Common breeding methods can be applied to the above two groups, however, the parents chosen for breeding under often cross pollinated crop need to be selfed for few generations to select desirable, homozygous lines.