Mitragyna Speciosa Korth, part of the Rubiaceae (coffee) family, is a tropical tree native to Southeast Asia, the Philippines and New Guinea, although it is now being cultivated in other areas. The most dominating location is Thailand (referred to as "Kratom", "kakuam", "ithang" or "thom") and Malaysia (referred to as "coriander" or "Biak-Biak") with cultivation has recently become dominate in Indonesia (known as the "Bali" or "Indo" Kratom). Leaves of trees have been historically used for its medicinal properties and producing energy by chewing the leaves or make a tea. This tree was first documented by botanists Dutch, Korthals. Korthals gave the genus its name because of the stigma of the first species examined resembles the shape of a bishop's miter. Other species of Mitragyna are found in India and Asia, among others: M. Tubulosa, M. parvifolia, M. hirsuta, M. diversifolia, M. rotundifolia and M. Kuntze. M. ciliate, M. Inermis, M. Stipulosa and M. Africanus widely grown in West Africa.
Over 25 alkaloids have been isolated from Kratom. Most alkaloids consist of three indoles and two oxindoles. Three indoles are mitragynine, paynanthine, and speciogynine - the first two are apparently unique to this species. Both oxindoles which mitraphylline and speciofoline. Other alkaloids present include other indoles, and oxindoles as ajmalicine, corynanthedine, mitraversine, rhychophylline, and stipulatine.
Kratom has been used for centuries in Thailand, recreationally and as antidiarrhetic. Its use as a substitute for opiates in Malaysia reported in the nineteenth century. Labour has been used to fight the boredom of physical work, similar to the use of coca in South America. Chemicals were investigated in 1920, and mitragynine was isolated in 1923. Kratom leaves become part of ethnobotanical trade in the United States and Europe in the mid-2000s."
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