Natural products from plants are still important sources for the development of drugs, despite their recent neglect in pharmaceutical discovery programmes. The rapidly dwindling number of species endangers the availability of these natural compounds, which are characterized by the immense chemical and functional diversity ultimately responsible for their pharmaceutical activity. Although many steps in the drug discovery process have been continuously modified during recent years, a common dilemma is still unresolved, i.e. the supply crisis for hits discovered in rare wild plants due to their inaccessibility or lack of reproducibility. New technology, combining tissue culture, functional genomics and metabolomics, shows promise to overcome these problems and even to supply a greater chemical diversity of compounds.

Due to their complex structure with several chiral centres important anticancer agents are still extracted from plants and not synthesized chemically on a commercial scale. Sustainable bioproduction of the compounds of interest may be achieved by plant in vitro cultures. Undifferentiated callus and suspension cultures, which can be cultivated in large bioreactors easily, very often fail to accumulate the compounds of interest, whereas shoot and root cultures as well hairy roots normally produce the same compounds as in the appropriate organs. The production of anticancer compounds, such as the alkaloids vinblastine, vincristine, paclitaxel (Taxol®), camptothecin, or the lignan podophyllotoxin, by plant in vitro cultures is reviewed. Taxanes can be produced in bioreactors using cell suspensions of various Taxus species with good yields; presently paclitaxel is produced on a commercial scale by Phyton Biotech (Germany). Camptothecin has low yields in suspension cultures of Camptotheca acuminata or Nothapodytes foetida (0.0003–0.01%), but a good production (0.1–0.3% dry wt) in root and hairy root cultures of Ophiorrhiza pumila, O. mungos and C. acuminata. Podophyllotoxin can be produced in cell suspension and root as well as hairy root cultures of Podophyllum and various Linum species up to 130 mg/l (Linum album cell suspensions); its derivative 6-methoxypodophyllotoxin is accumulated in hairy roots of L. persicum up to about 500 mg/l. The in vitro production of dimeric indole alkaloids in Catharanthus roseus has failed so far both in undifferentiated and differentiated in vitro cultures. In cases where in vitro cultures show good yields, they can be employed in biotechnology for the sustainable production of valuable products.

In China, medicinal plants enjoy an inherent and prominent role in the general health service. Due to excessive collection in the wild of rare and endangered plants, the natural resources of medicinal plants are depleting fast. In order to protect the medicinal plant resources, the Chinese government has implemented Good Agricultural Practice (GAP) programmes to cultivate the main popular medicinal plants in China. Thus far, around 800 GAP cultivation bases have been established nationwide and the total cultivation area of medicinal plants has reached 5000 km2. Besides GAP cultivation of medicinal plants, tissue cultural biotechnology has been applied to serve as an alternative for the supply of medicinal plant materials in China. Thus far, shoot production by tissue culture technology has been successful in medicinal plants such as Anoectochilus formosanus, Dalbergia odorifera, Dendrobium, Momordica grosvenorii, Pseudostellaria heterophylla and Taxus chinensis. In addition, the cell culture of Lithospermum erythrorhizon and Saussurea involucrata has been industrialized in 300–20,000-litre bioreactors. Besides the production of shoot and cell culture in bioreactors, tissue culture technology is also being practised for the conservation of rare medicinal plants.

The endangered alpine plant Aconitum heterophyllum was conserved under ex situ conditions (greenhouse and open) of Palampur by overcoming seed dormancy and plant establishment through hot water treatment (40–60 °C for 30–120 s) of seeds. High seed germination (88 and 76%) was obtained when seeds were treated with hot water at 45 and 50 °C for 90 s. Correlation studies also revealed that treatment enhanced vegetative growth and reproductive yield of the plants. The total alkaloid content of the roots and rhizomes of the plants growing under ex situ conditions was lower than the ones collected from the natural habitat in the 1-year-old plants. However, in the 2-year-old plants, it was almost at par with the ones collected from nature. The life cycle of the plants growing under ex situ conditions also did not vary largely from the plants growing under in situ conditions. Therefore, the present study indicates the successful adaptation of A. heterophyllum plants in conditions other than their natural habitat and hence its potential for sustainable commercialization.

Millefolii herba is one of the oldest and most important drugs in Lithuania, used both in folk and official medicine. The raw material is usually gathered from spontaneous populations. It would be reasonable to develop methods to identify the populations which produce high plant biomass and accumulate high levels of proazulenes. The quantitative variation of proazulenes and their relationships with phytosociological dependence and morphological characters of Achillea millefolium from wild populations has been examined. The vegetation records were made at 140 growing sites of A. millefolium. The species was found in 29 types of community representing different growing habitats. The resources of milfoils prevailed in dry grasslands of Arrhenatheretalia communities and ruderal habitats of Dauco-Meliliotion. The data on productivity and morphological characters were subjected to multivariate statistical analysis. A hierarchical cluster analysis indicated that higher productivity of A. millefolium populations was associated with their dependence on ruderal and segetal communities. The testing of A. millefolium plants revealed high variation for proazulenes in different communities. The proazulene-containing plants have been identified in 38% of all analysed cases. In the highest segetal and wasteland communities of Agropyretalia repentis, Sisybietalia, Digitario-Setarion, Aperion spicae-venti, Senecion fluviatilis only proazulene-free plants were found. Results of the ANOVA showed the proazulene-containing and proazulene-free plants significantly differed (P<0.05) for width of leaves and number of nodes. The presence of nodes in high number and narrow leaves in high proazulene-containing plants distinctly marked them from the proazulene-free plants. The study raised the possibility that selection based on the two morphological marker traits (node number and leaf width) and proazulene distribution in the populations would be effective for rapid identification of highly productive population(s) of pharmaceutical importance.

Dendrobium Sw., a member of the family Orchidaceae, includes approximately 1100 species distributed in different parts of the world. In China, the genus is represented by 76 species and two varieties, of which D. loddigesii, D. fimbriatum, D. chrysanthum, D. officinale (=D. candidum) and D. nobile are listed in the Chinese Pharmacopoeia as the source material for Herba Dendrobii (Shihu). Because of increased demand and high price, Herba Dendrobii is often adulterated in the trade by other related species. Many Dendrobium species are over-collected from the wild and are listed under endangered taxa in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Therefore, a reliable authentication method is needed to regulate the trade and help conserve the species from unscrupulous collections. This review describes the present status of using medicinal Dendrobium in China, current approaches to authenticate medicinal Dendrobium plants and Herba Dendrobii, and the efforts under way towards the development of DNA microarrays to facilitate differentiation/identification of genuine material in complex Chinese medicinal formulations.

Hydro-distilled essential oils from fruits, aerial parts (without fruits) and roots of Pimpinellaspecies native to Turkey and their phylogenetic relationships to one another were examined. Phytochemical investigation of the essential oils of 19 species resulted in isolation of 16 phenylpropanoids, four sesquiterpenes and two azulene-type norsesquiterpenes. The structures of the isolated compounds were determined primarily from 1D- and 2D-NMR experiments as well as liquid chromatography–mass spectrometry and gas chromatography–mass spectrometry. Phylogenetic relationships among 26 species were evaluated using ITS 1, ITS 4 nuclear rDNA and psbA-trnH cpDNA sequences. In this study, significance and occurrence of phenylpropanoids, azulenes and geijerenes are discussed from a phylogenetic, chemical and biosynthetic perspective. The distribution of different classes of compounds and their putative associations with one another as per current knowledge of their biosynthetic pathways indicates that this information, in conjunction with the phylogeny, could provide valuable information regarding the presence and perhaps evolution of the different classes of compounds. Analysis of the phenylpropanoid components indicates that (E)-anethole is an obligatory intermediate of this pathway. The various Pimpinellaspecies differ primarily in their ability to acylate anethole, suggesting that while the pathway leading to anethole is common to this genus, species differ in their enzymatic machinery leading to acylate. The relationship between azulenes and geijerenes is not as intuitive, but all Pimpinellaspecies analysed in this study have the biochemical machinery required to synthesize these chemical classes.

Polyploidization is often accompanied by increased cell size and conspicuous changes in secondary metabolism. Where vegetative plant organs are the source of secondary metabolites, as is the case with most medicinal plants, ploidy manipulations such as direct chromosome doubling or allopolyploidization provide a rapid means to realize enhanced production of phyto-pharmaceuticals. Supported with prospective examples, this article illustrates the potential of genomic and ploidy manipulation to enhance the resourcing of pharmaceuticals of plant origin and suggests some appropriate strategies for optimum utilization.

Numerous factors influence the chemical quality of medicinal plants from crop establishment to extraction of raw material. The most important ones are described using the example of Hypericum perforatum. Optimization of these factors contributes to the objective of producing a high-quality drug, and a method consisting of three scientific approaches (technological, agronomical, plant breeding) is presented. All data concerning the plant (biology, physiology and environmental impacts) and the active components and by-products (pathway, localization and stability) are useful to adapt and to develop management sequences. Although plant breeding appears to be the principal way of improvement, and gives good results in terms of resistance to pathogens, active component content and yield; the agronomical and the technological approaches are also very important. The technological approach after harvesting is especially important to avoid degradation of the active components and to induce, in some cases, the transformation of by-products to those molecules sought. This integrated method (plant breeding and agronomical and chemical approaches) requires research on different levels of organization from molecule to field, and includes all processing systems from farmers to chemists.

Well-defined descriptors are an indispensable tool for management, maintenance and utilization of plant genetic resources. The International Plant Genetic Resources Institute (IPGRI), the International Union for the Protection of New Varieties of Plants (UPOV) and national authorities have published descriptor lists for a great variety of agricultural and horticultural crops, but only for a few species belonging to the group of medicinal and aromatic plants (MAP). Forty years of experiences with the use of descriptors in MAP mainly in the field of breeding research are communicated to support forthcoming efforts in elaborating new descriptors lists. The deliberations focus on some specifics of these minor crops, classifying the descriptors to the following groups: object, experimental data, sample specification, characteristics—growth, development, flower and reproduction biology, cytological traits, molecular traits, biotic and abiotic stress susceptibility, yield, quality differentiated in morphology-dependent quality traits, constituents, sensory quality, and impurities. MAP-specific descriptors are exemplified and the principles of important determination methods are explained. Most of the general available UPOV and IPGRI descriptors are applicable also for MAP.

An integrated and interdisciplinary research programme with native medicinal plants from tropical forests has been performed in order to obtain new forest products for sustainable use in regional markets vis-à-vis ecosystem conservation. For the success of this programme ethnopharmacological studies are very important with respect to (i) identification of useful plants including medicinal and aromatic species; (ii) recuperation and preservation of traditional knowledge about native plants; and (iii) identification of potential plants with economic value. The plants are selected with a view to evaluate efficacy and safety (pharmacological and toxicological studies), and phytochemical profile and quality control (phytochemical and chromatographic characterization). These studies are very important to add value to plant products and also to mitigate unscrupulous exploitation of medicinal plants by local communities, since multiple use of plants represents an excellent strategy for sustaining the tropical ecosystem through ex situ and in situ conservation. Thus, conservation of tropical resources is possible in conjunction with improvements in the quality of life of the traditional communities and production of new products with therapeutic, cosmetic and ‘cosmeceutic’ value.

Malaria has been treated for over 350 years with quinine and quinine-derived drugs. However, in several areas of the world, some strains of the malarial parasite Plasmodium falciparum have developed resistance against these drugs. Recently, the World Health Organization (WHO) recommended the use of artemisinin-combination treatments (ACT) as the first-line treatment for multidrug-resistant falciparum malaria. The WHO estimates that current supplies of artemisinin are sufficient for only 30 million ACT, and is foreseeing the need for 130–220 million ACT in 2005 (WHO, 2004). Current research on the production of synthetic artemisinin-like compounds by the Roll Back Malaria project, pharmaceutical companies and academia resulted in a promising synthetic artemisinin-like compound (OZ277) which is currently undergoing phase I clinical trials. In about 5 years this drug is expected to be approved and made available to the public, however, meeting current global demands for ACT depends on the immediate availability of affordable artemisinin-derived drugs. This will involve expansion of the area under cultivation of Artemisia annua and improved methods of cultivation and processing of raw material, associated with more efficient methods for extraction and purification of artemisinin from plant material. This review addresses the agricultural, environmental and genetic aspects that may be useful in the successful large-scale cultivation of A. annua and for producing the antimalarial artemisinin in areas where it is urgently needed today. It also includes geographic aspects (latitude and altitude), which will help make decisions about crop establishment in tropical countries, and includes a list of Good Agricultural and Collection Practices for A. annua.

The genus Curcuma (family Zingiberaceae) comprising over 80 species of rhizomatous herbs, is endowed with widespread adaptation from sea level to altitude as high as 2000 m in the Western Ghats and Himalayas. Having originated in the Indo-Malayan region, the genus is widely distributed in the tropics of Asia to Africa and Australia. Curcuma species exhibit inter- and intra-specific variation for the biologically active principles coupled with morphological variation with respect to the above-ground vegetative and floral characters as well as the below-ground rhizome features besides for curcumin, oleoresin and essential oil. Curcuma is gaining importance world over as a potential source of new drug(s) to combat a variety of ailments as the species contain molecules credited with anti-inflammatory, hypocholestraemic, choleratic, antimicrobial, insect repellent, antirheumatic, antifibrotic, antivenomous, antiviral, antidiabetic, antihepatotoxic as well as anticancerous properties. Turmeric oil is also used in aromatherapy and in the perfume industry. Though the traditional Indian Ayurvedic system of medicine and Chinese medicine long ago recognized the medicinal property of turmeric in its crude form, the last few decades have witnessed extensive research interests in the biological activity and pharmacological actions of Curcuma, especially the cultivated species. Turmeric powder obtained from rhizomes of Curcuma longa or related species is extensively used as a spice, food preservative and colouring material, in religious applications as well as a household remedy for bilary and hepatic disorders, anorexia, diabetic wounds, rheumatism and sinusitis in India, China and South-East Asia and in folk medicine. Cucuminoids, the biologically active principles from Curcuma, promise a potential role in the control of rheumatism, carcinogenesis and oxidative stress-related pathogenesis. Curcuma longa L. syn. Curcuma domestica Val., common turmeric, is the most economically valuable member of the genus having over 150,000 hectares under its cultivation in India. In addition to Curcuma longa, the other economically important species of the genus are C. aromatica, used in medicine and toiletry articles, C. kwangsiensis, C. ochrorhiza, C. pierreana, C. zedoaria, C. caesia etc. used in folk medicines of the South-East Asian nations; C. alismatifolia, C. roscoeana etc. with floricultural importance; Curcuma amada used as medicine, and in a variety of culinary preparations, pickles and salads, and C. zedoaria, C. malabarica, C. pseudomontana, C. montana, C. decipiens, C. angustifolia, C. rubescens, C. haritha, C. caulina etc. all used in arrowroot manufacturing. Crop improvement work has been attempted mainly in C. longa and to a little extent in C. amada. At present there are about 20 improved varieties of C. longa in India and one in C. amada, evolved through germplasm/clonal selection, mutation breeding or open-pollinated progeny (true turmeric seedlings) selection. Though work on morphological characterization of Curcuma species has been attempted, its molecular characterization is in a nascent stage except for some genetic fidelity studies of micropropagated plants and isozyme-based characterization. The genus has also been examined from the biochemical profiling and anatomical characterization angle. This article is intended to provide an overview of biological diversity in the genus Curcuma from a utilitarian and bio-prospection viewpoint.

Plantago ovata is the cultivated and economically important species in the monotypic genus Plantago. P. ovata is a short-stemmed annual herb, 10–45 cm tall. The species is generally an in-breeder. The seed husk of this plant is commonly called Psyllium or Isabgol (in Hindi), which is a very effective laxative. Other usages of Isabgol are in ice cream making, cosmetics, printing and finishing. The intake of husk also reduces blood cholesterol levels. Isabgol is commercially very important as its export earns India foreign exchange worth INR 2.5 billion (US$1=44 INR). The plant is cultivated on a large scale in western India. In Gujarat, it is cultivated in about 144,000 ha of land, yielding 720 kg/ha. P. ovata has a narrow genetic base, and the lack of variability is on account of low chromosome number, small chromosome size, presence of high heterochromatin in the chromosomes, low chiasmata frequency and low recombination index. The genome size of the species is ∼500 Mb. Different breeding methods, namely selection, hybridization, induced mutations, polyploidy and tissue culture, have been used for genetic improvement of this plant. Except selections, which have led to isolation of a few varieties, the results of other methods have not been encouraging. P. ovata has about 200 wild allies, some of which are medicinally important. These wild species constitute a rich resource of important genes, which if transferred to cultivated species could revolutionize the production of Isabgol. The present paper highlights various aspects of genetic diversity, cultivation and utilization of this important medicinal plant, and suggests the prospects of genetic manipulation.

Chlorophytum borivilianum is an important medicinal plant known as ‘Safed musli’, used in many Ayurvedic vital tonics and aphrodisiac formulations. The species was first described from India in 1954 and reached rare status in nature due to overexploitation. Owing to its increased demand, the species has attracted the attention of farmers as well as researchers in several institutions. The present paper deals with various research aspects such as conservation biology, cytology, chemistry, plant genetic resources, micropropagation, crop management, etc. conducted on the crop for the last two decades in India. The species is diploid 2n=4x=28 and is mainly vegetatively propagated. Seeds remain dormant for nearly 10 months and also suffer from poor germination. Fleshy roots of the species contain saponins having therapeutic value. Germplasm collections made from different states in India show the occurrence of wide genetic variability in terms of plant type, maturity period, growth and yield characters, and size and shape of fleshy roots. Although the species is cross-pollinated in nature, self-pollination is also feasible artificially. One high-yielding cultivar and two high-yielding morphotypes have been recently identified. A micropropagation protocol using different explants has been standardized and agrotechnology for cultivation developed. Successful use of synthetic seed has also been reported. The article presents a comprehensive overview of the current state of research in the species with due emphasis on future thrust and possibilities.

Lichen-forming fungi are unique organisms, producing biologically active metabolites with a great variety of effects, including antibiotic, antimycobacterial, antiviral, anti-inflammatory, analgesic, antipyretic, antiproliferative and cytotoxic activities. However, only very limited numbers of lichen substances have been screened for their biological activities and their therapeutic potential in medicine. This is certainly due to the difficulties encountered in identification of the species, collection of bulk quantities, and the isolation of pure substances for structure determination and testing activity. Recently, possibilities for bypassing some of these former difficulties have arisen by the introduction of new techniques. This includes axenic cultivation for production of the genuine compounds or new ones, extraction of focused compounds, or synthesis of natural products or their derivatives for testing. Utilizing these new opportunities, the discovery of novel active metabolites, which could serve as lead compounds, is significantly facilitated. At the same time, the evolution of secondary metabolite patterns is studied using phylogenetic approaches. Yet, the genetic background of the complex chemical patterns is poorly understood. The scattered occurrence of some compounds suggests that their production evolved either in parallel or that ancient biosynthetic pathways are abandoned in many lineages. At least, studies on polyketide synthase genes from different lichen groups suggest a high level of gene paralogy. In this context, clades of orthologous polyketide synthase genes, which are often shared with distantly related non-lichenized fungi, can roughly be identified by their sequence similarity and their similar patterns of substitution rates. The functional assignment of paralogs is nevertheless difficult and reasonable only in a few cases. A global approach of the lichen metabolomic features appears to be essential in developing new and viable biotechnological processes which could afford suitable amounts of unique lichen compounds.

Mushrooms are the fungi that have been used as food since time immemorial. Nutritionally they are a valuable source of health food, which is low in calories, and rich in carbohydrates, essential amino acids, fibre, important vitamins and minerals. Mushrooms have also been used in medicine for centuries in the Orient but their potential as health potentiators and elicitors of immune system is recent. In the last two decades there has been an upsurge on the use of mushrooms as nutraceuticals and many edible species have been thoroughly investigated and authenticated for medicinal use. The species that have been properly analysed for medicinal value are: Ganoderma lucidum (Reishi), Lentinus edodes (Shiitake), Grifola frondosa (Maitake), Agaricus blazei (Hime-matsutake), Cordyceps militaris (Caterpillar fungus), Pleurotus ostreatus (Oyster mushroom) and Hericium erinaceous (Lions mane). There are many more species of cultivated and wild edible and non-edible mushrooms that have been analysed for both their nutritional and nutraceutical components but to a lesser extent than those listed above. The active constituents found in mushrooms are polysaccharides, dietary fibres, oligosaccharides, triterpenoids, peptides and proteins, alcohols and phenols, and mineral elements such as zinc, copper, iodine, selenium and iron, vitamins, amino acids etc. These have been found to boost the immune system, have anti-cancerous properties, act as anti-hypercholesterolaemic and hepato-protective agents, show anti-HIV activity and anti-viral activity, and ameliorate the toxic effect of chemo- and radiotherapy. Many of the species are known to be aphrodisiacs. Many commercial products from these mushrooms are available in the market. Prominent among these are: Lentinan from Lentinus edodes, Concord Sunchih and Reishi Plus from Ganoderma lucidum, Grifon from Grifola frondosa and Didanosine from Cordyceps militaris. The nutraceuticals have been found to relieve the stress and pressure of modern society by stimulating both basic and secondary immune responses of the immune system. There are more than 5000 species of mushrooms recorded from all over the world out of which around 2000 are identified as edible. A large number of the species are yet to be analysed for their nutraceutical/medicinal potential.

Herbal medicine is used worldwide either as a sole treatment method or as part of a comprehensive treatment plan alongside orthodox methods of diagnosis and treatment. A survey reported that, in the USA, nearly one-sixth of women took at least one herbal product in 2000. Despite their widespread use, numerous reports show that the herbal products available to consumers are of variable quality. This disparity in quality of herbal preparations can be attributed to the fact that their production is complicated. To produce high-quality herbal products, attention must be paid to, among others, phytochemical variations due to plant breed, organ specificity, stages of growth, cultivation parameters, contamination by microbial and chemical agents, substitution, adulteration with synthetic drugs, heavy metal contamination, storage and extraction. This review focuses on organ specificity, seasonal variations, the effect of drying and storage, and the extraction of phytochemical constituents. Special emphasis is placed on the four most frequently used herbal products in the USA: echinacea, Ginkgo biloba, ginseng and St John's Wort.