These are small evergreen trees or shrubs approximately 6–12 m tall. The bark is reddish brown, thin and scaly. Individual trees are either male or female with dioecious flowers. Bark and more recently leaves and twigs of T. wallichiana and other Taxus species are harvested for extraction of paclitaxel, 10-DAB and other taxanes. Although not rare Taxus…
Classification of Taxus genus of the Taxaceae family of trees and shrubs is characterized alternately as notoriously difficult or controversial with the species described being discouragingly similar. Depending on the taxonomic authority consulted, the genus contains anywhere from one species with numerous varieties to 24 species with 55 varieties. These are distributed across northern temperate…
Taxol or paclitaxel is a diterpenoid pseudoalkaloid first obtained from the bark of North American Taxus species Taxus brevifolia Nutt (Pacific Yew). Family: Taxaceae Common Names English: Yew tree – Pacific yew, Himalayan yew Hindi: Barmi, Talispatra Commercial Importance Leaves, twigs, bark and roots of Taxus species contain a unique class of diterpenoid alkaloids called taxanes that…
India at one time had a monopoly on the supply of rauwolfia to the world market. It is among the top 178 medicinal plants considered to be in high volume trade and consumption with global demand for rauwolfia estimated in the early 1980s to be 100–150 tonnes annually. Today it is growing significantly with the…
Rauwolfia is considered an important therapeutic option for patients with mild to moderate essential hypertension not improved by lifestyle changes. Rauwolfia alkaloids bind irreversibly to catecholamine storage granules in neurons, primarily those in the mid-brain autonomic centres and cells in the adrenal medulla, causing depletion of catecholamines and 5-HT from those granules. As a result…
In India, rauwolfia has been employed for centuries in the treatment of various central nervous system (CNS) disorders, including anxiety states, maniacal behaviour associated with psychosis, schizophrenia, insanity, insomnia and epilepsy. Extracts of the roots are valued for the treatment of intestinal disorders and also as an anthelmintic: mixed with other plant extracts, they have…
The root system consists of a prominent tuberous soft tap root upto 6 cm in diameter when fresh and having a corky outer bark with longitudinal fissures. Generally roots and sometimes leaves are harvested. Roots are harvested during winter months for maximal alkaloidal content. The root is to be harvested 15–36 months after planting to…
The root and the root bark which constitute 40% to 60% of the whole root contain over 60 indole alkaloids, the most significant being reserpine, rescinnamine, deserpidine, reserpinine, serpinine, serpentine, ajmaline, ajmalicine, rauwolfinine and yohimbine. The root bark contains more than 90% of total alkaloids, which varies from 1.4–3% depending on location, season and soil…
An erect, small, evergreen perennial semi-shrub growing upto 50 cm tall, the species is wide ranging in Asia and found in India, Bangladesh, Bhutan, China, Indonesia, Malaysia, Myanmar, Nepal, Pakistan, Sri Lanka, Thailand and Vietnam. It is found in almost all parts of India up to an altitude of 1000 m, and is more common…
An important component of traditional medicine in India, the drug is a source of hypotensive alkaloids, principal of which are reserpine, rescinnamine and ajmaline. First isolated from the roots in the early 1950s, it quickly became important in the treatment of hypertension and mental illness through its effect as a tranquillizer. Use has decreased in…