Medicinal Plants of the Himalayas: Advances and Insights (original) (raw)

“Man, ever desirous of knowledge, has already explored many things, but more and greater still remains concealed; perhaps reserved for far distant generations, who shall prosecute the examination of their Creator’s work in remote countries, and make many discoveries for the pleasure and convenience of life” (Linnaeus, 1754). One such vast unexplored region and a biodiversity hot spot, lies between two great ancient civilizations of India and China and is famous as “The Great Himalayan Region”. The main Himalaya range runs west to east, from the Indus river valley to the Brahmaputra river valley, forming an arc 2,400 km long, which varies in width from 400 km in the western Kashmir-Xinjiang region to 150 km in the eastern Tibet-Arunachal Pradesh region. The range consists of three coextensive sub-ranges, with the northernmost, and highest, known as the Great or Inner Himalayas. The ancient religious scripture of Hindus, Atharvaveda is the earliest celebrated treatise mentioning the use of medicinal plants of the region. Atharvaveda contains 114 hymns or formulations for the treatment of diseases. Ayurveda, a system of traditional medicine native to the Indian subcontinent, originated in and developed from these hymns. The Suśruta Saṃhitā and the Charaka Saṃhitā are two important works on this traditional system of medicine. In addition there is a famous reference in Valmiki’s Ramayana, a religious scripture of Hindus, about the existence of rare medicinal plant Sanjivani (Selaginella bryopteris) in Himalayas, which saved the life of Lakshmana (brother of the Hindu god Lord Rama). Over the centuries people have depended on these medicinal plants for treating daily ailments like cough, colds, indigestion, ulcers, sore eyes etc. In fact Sir Lawrence, a British Settlement Commissioner in his book, ‘The Valley of Kashmir’ (1895) refers to this point as, “when I have made inquiries as to various herbs which I have seen in the valley and on hillsides, I am always told that they are hot and good for cold humours, cold and good for hot humours, dry and beneficial to damp humours, damp and beneficial to dry humours.” In this Special Issue (SI) on Himalayan MAPS, an attempt has been made to present various issues pertaining to conservation, documentation, biotechnological applications and medicinal uses of plants of Himalayan region. The SI comprises of 13 research articles related to different areas of plant biotechnology. In the first paper Bantawa et al. take-up an important highly valued endangered medicinal plant of Indo-China Himalayas viz. Picrorhiza scrophulariiflora Pennell and describe in detail its micropropagation. This study is first such report on this plant and illustrates the usefulness of additives for mass propagation and germplasm conservation. In a similar study Hamid et al. describe a method for in vitro shoot organogenesis of Cichorium intybus using shoot tips as explants. Cichorium intybus is known for its anti-cancerous and anti-hepatotoxic properties and their successful transfer to pots with 60% survival percentage is a step forward towards its ex situ conservation. The potential of Agrobacterium rhizogenes-mediated genetic transformation for the synthesis of phytomolecules of high pharmaceutical value is well established. Goel et al. present the first report of reserpine production in quantifiable amounts from the Agrobacterium rhizogenes-generated transgenic hairy roots of Rauwolfia serpentine, whose root-extracts have been used for centuries in Ayurvedic medicine. In one clone the reserpine level was found to be 2- 3 times that of field grown roots, which is quite encouraging. Supply of authentic medicinal plants to herbal drug industry is an important requisite for enabling their commercial use in production of genuine phytoceuticals. An authentic identification system based on amplified fragment length polymorphism (AFLP) for Aconitum heterophyllum, A. violaceum, A. balfourii and A. ferox has been reported in an original research paper by Misra et al., which could be used for checking adulteration-related problems faced by commercial users of the herb. Rasool et al. compared antioxidant and antimicrobial properties of wild and in vitro-regenerated plants of a Kashmir Himalayan perennial medicinal herb, Prunella vulgaris. Their study is probably the first report giving evidence that in vitro grown P. vulgaris has antioxidant and antibacterial activities similar to that of wild, suggesting the substitution of wild P. vulgaris with tissue culture raised plants for use in pharmaceutical industry. In another study on antibacterial activity, the potential of methanolic extract of seeds and leaves of Euryale ferox was tested against nine clinically isolated bacterial strains by Parray et al. The broad spectrum activity displayed by these extracts appears to provide logic for the use of E. ferox as ethno-medicine in urinary tract infections. The issues related to ethno-medicinal uses and overexploitation of medicinal plants of Haigad watershed of Kumaun Himalaya have been discussed by Joshi et al. They argue that for sustainable use, in addition to rapid conservation efforts, farmers should be involved in the cultivation of medicinal plants. An exhaustive ethno-botanical survey on phyto-diversity, spanning over more than 250 species, of Parvati Valley in Northwestern Himalayas described by Sharma et al. is highly informative. They stress the involvement of local inhabitants for conservation of indigenous knowledge and traditional practices. In a similar study on medicinal plants of west Nepal, Kunwar et al. compare indigenous knowledge of therapies of 48 medicinal plants with the latest common pharmacological findings, suggesting complementarities and thus forming base for use in modern therapeutic medicine. Similar correlation was reported by Ryakala et al. while studying the ethnobotany of 52 plant species used to cure diabetes by the inhabitants of north eastern India. Raj et al. have screened phytochemical constituents of 21 medicinal plants used in traditional Amchi system of medicine in the Ladakh region of India. The significance of these plants is discussed in the context of their role in ethnomedicine All these studies have generated the possibilities of using the unexplored plants as potential sources of future drugs. Verma et al. have contributed an informative paper describing the chemical composition of leaf and flower essential oils of Thymus serpyllum and T. linearis from Western Himalaya, while Hamid et al. discuss the impact of chromium on the oxidative defense system of Brassica juncea L., a medicinally important plant commonly used as a diuretic and stimulant. I hope that the scientists working on medicinal plants will find this Special Issue helpful in moving forward in their important quest of contributing in the area of medicine, drug discovery, and conservation of medicinal plants etc. I would like to thank Dr. Jaime A. Teixeira da Silva and Ms. Kasumi Shima at Global Science Books Ltd., UK for their cooperation and helpful suggestions; and my family for their understanding and support during the prolonged and time-consuming work on this volume.