Black catechu Biological Sources, Morphological Features, Chemical Constituents, and Uses
Black Catechu
Synonyms:- Gambier, Catechu Biological source:- It is an aqueous extract prepared from the leaves and young shoots of Uncaria gambier Roxburgh. Family: Rubiaceae. Geographical source:- It is a climbing shrub native to Malay Archipelago and largely cultivated on islands of Singapore and Sumatra. This drug was used in India for the chewing purpose with Piper betle (betel) leaf. Cultivation and Collection:-- Plantation is done in damp soil and at an altitude of 500 ft above the sea level.
- The nursery raised seedlings of about 9 months are planted at about 3 metre distances in between.
- When the plant reaches height of about 2 meter coppicing has been done.
- From about eight years after plantation to twenty years age of plant, the yield is at its maximum.
- The shoots are cut down with a broad bladed knife and put it in special type of vessel known as ‘Cauldron’ which is made of hard wood with an iron bottom.
- The leaves and young shoots are boiled in ‘Cauldron’ for about three hours with continuous stirring of the content.
- The decoction is evaporated till it becomes thick and pasty with yellowish green colour. The contents transferred into wooden tubs and allow cooling.
- After about ten minutes the semi crystallised magma is poured into wooden trays to settle down. It is cut into cubes with a wooden knife while the preparation is still moist and sun dried.
- Much amount of Gambier is filled into kerosene tins to solidify to obtain large blocks which are marketed. The cube shape of Gambier is preferred for pharmaceutical purpose.
- Form: Cubes, rectangular blocks or irregular broken pieces.
- Colour: Dark reddish brown.
- Odour: None.
- Taste: First bitter and astringent afterwards sweetish.
Immunomodulatory activities of Acacia catechu, a traditional thirst quencher of South India
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