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About Authors:
Sharda roy*, vikas chandra roy, dr. R. C. Roy
Address Faculty of Pharmaceutical Sciences. Global College of Pharmacy.
Kahnpur Khui. Punjab.

Mitragyna parvifolia
is a medium to large size tree belonging to the family Rubiaceae. It is popularly known as Kaim and is found growing gregariously throughout the drier parts of India, Pakistan and Srilanka. The aerial parts, stem-bark and roots of the tree contain various indolic (tetrahydroalstonine, akkuamigine, hirsuteine etc) and oxindolic (mitraphylline, isomitraphylline, pteropodine, isopteropodine etc) alkaloids. Important variations in the nature and quantity of alkaloids present in different parts of the plant are visible with change in geographical locations. In addition, various parts of the tree such as fruit juice, leaves and stem bark have been used in the traditional system of medicine by the natives and tribal since times immemorial. Mitragyna parvifolia has also got diverse medicinal and therapeutic properties such as analgesic, antipyretic, anti-inflammatory, antiarthritic, anthelmentic, antioxidant etc which have been validated scientifically. In this study we have critically reviewed the pharmacognostic and chemical profile, the traditional and the scientifically validated bioactivities of the plant.

Reference Id: PHARMATUTOR-ART-1594

Mitragyna parvifolia
(Roxb) Korth [M. parvifolia] commonly known as Kadamb, belongs to family Rubiaceae1. The genus was given the nameMitragynaby Korthals because the shape of the stigmas in the species he examined resembled a bishop's mitre. The genus Mitragyna is a short genus comprising of 10 species. The plant is native to Indian origin but is found growing gregariously in swampy territories in the tropical and sub-tropical regions of Africa and Asia. The plant is known in different parts of the country by various common names:Kaim (English); Nir-kadambai (Tamil); Vimba, Sirakadambu, Kadamba, Neerkadambu, Poochakadambu, Rose kadambu, Veembu (Malayalam); Kongu, Nayekadambe (Kannada) 2.

The Kaim is a medium to large deciduous tree with rounded crown mainly arboreal in character while some species grow to a height of about 30 meters. It is found throughout the greater parts of India up to an altitude of 1200 metres. Tree is found scattered in deciduous forests and develops best in well drained deep soil. It is found growing gregariously in low lying areas around banks and swamps.

Mitragyna species are characterized by the globular flowering head each containing up to 120 florets. The inflorescence is a dichasial cyme and the fruit is a capsule containing numerous small flat seeds. The young woody shoots bear 10-12 leaves arranged in opposite and decussate pairs. The bole is often short, flutted and buttressed. The bark is grey, smooth and exfoliating. The wood is pale yellow when first exposed but turns light grayish brown on ageing. Natural reproduction takes place by the scattering of seeds in hot season. Germination takes place in the rainy season 2.


Chemical constituents
M. parvifolia
is an important tree blessed with large number of important phytoconstituents especially alkaloids. The alkaloids of Mitragyna parvifolia are of both indolic and oxindolic type 3 which may be divided into two groups:
1.The Closed E ring alkaloids
2.The Open E ring alkaloids ( E seco) (fig- 1, fig-2)

Oxindole alkaloids are an important group of alkaloids which contain the oxindole moiety often associated with significant biological activity. E seco oxindole alkaloids act on the central nervous system whereas Closed E ring oxindole alkaloids affect cellular immune system 4. The spiro (indole-pyrrolidine) ring system is a frequently encountered structural portion in these alkaloids 5. The Indole alkaloids of Mitragyna parvifolia are also of considerable importance as they are the precursors or the starting materials for the biogenesis of corresponding oxindole alkaloids (table 1).

All the alkaloids have asymmetric centres at C (3), C (15) and C (20) though all those isolated so far have C (15)-Hα. The closed E ring alkaloids also have an asymmetric centre at C (19) which, in all the known Mitragyna alkaloids is C (19)- Hβ. The E seco alkaloids may show geometric isomerisation because of the double bond between C (16) and C (17) though all the known alkaloids possess a C (17) –H cis to the ester group at C (16). In addition, the oxindole alkaloids have an asymmetric centre at C (17). Alkaloids in which the lactam carbonyl lies below the plane of the C ring being termed the A series and those in which the lactam carbonyl lies above the C ring being termed the B series (fig-3).

Further in both types of oxindole alkaloids the lone pair of electrons in N (4) may either be on the same side of the C (7) as the lactam carbonyl or on the opposite side; the former are known as syn and the latter as anti alkaloids. The oxindole alkaloids readily isomerise about C (7) and C (3) to give a mixture of isomers. Substituents may occur in the aromatic ring but always at C (9)- R1 being either a hydroxy or a methoxy group. In the E seco alkaloids RII may be either CH2 CH3 or CH=CH2 6.

Important facts revealed by Configurational Studies
1.      When indoles and oxindoles are present in the same plant the D/E ring system are identical in both types.
2.      The Closed E ring alkaloids have C (19)-Hβ.
3.      The indoles are present in major quantities as their least stable configuration i.e pseudo and epiallo7.

Large quantities of indole alkaloids occur in root bark than in the leaves 8, suggesting that biogenesis does not take place in leaves but in roots and only certain alkaloids are transferred to the aerial parts and the amounts transferred varies from time to time. The biogenesis of indole alkaloids is through the geraniol-iridodial pathway. The plant synthesizes the thermodynamically more stable indole alkaloids and these alkaloids:
1.      Isomerize to give thermodynamically less stable isomers or
2.      Both indole isomers are converted to the corresponding oxindoles (table 2).


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