Asana consists of heart-wood of Pterocarpus marsupium Roxb. (Fam. Leguminosae), a moderate to large sized, deciduous tree, upto 30 m high and 2.5 m in girth, with straight clear bole, found mostly throughout Gujarat, Madhya Pradesh Bihar and Orissa.
Sanskrit : Bijaka, Pitasira, Asanaka, Bijasira
Assamese : Aajar
Bengali : Piyasala, Pitasala
English : Indian Kino Tree
Gujrati : Biyo
Hindi : Vijayasara, Bija
Kannada : Bijasara, Asana
Kashmiri : Lal Chandeur
Malayalam : Venga
Marathi : Bibala
Oriya : Piashala
Punjabi : Chandan Lal, Channanlal
Tamil : Vengai
Telugu : Yegi, Vegisa
Urdu : Bijasar
Drug occurs as irregular pieces in variable size and thickness, golden yellowish brown with darker streaks, on soaking In water gives yellow colour solution with blue fluorescence strong, tough, very hard, moderately heavy, fracture, difficult to break but brittle, taste, astringent.
Transverse section shows alternating bands of larger and smaller polygonal cells
consisting of tracheids, fibre tracheids, xylem parenchyma and traversed by xylem rays, numerous xylem vessels distributed throughout, in singles or in groups of 2-3, showing tyloses filled with tannin, in isolated preparations, vessels, drum or barrel shaped with well-marked perforation rims and bordered pits, tracheids numerous, long, thick-walled with tapering ends and simple pits, fibre tracheids elongated, thick-walled with narrow lumen and simple pits, xylem parenchyma rectangular with simple pits, paratracheal, surrounding vessels, xylem rays uni-to-biseriate, 3-5-7 cells high, prismatic crystals of calcium oxalate present in crystal fibres, starch absent.
Powder: Brown to chocolate colour, under microscope shows vessels with bordered pits, fibre tracheids, tracheids, fragments of xylem rays and few crystal fibres, starch absent.
CONSTITUENTS – Alkaloids and resin.
PROPERTIES AND ACTION
Rasa : Katu, Tikta, Kashiya
Guna : Laghu, Ruksha
Virya : Ushna
Vipaka : Katu
Karma : Kushhaghna, Rasiyana, Kaphapittasimaka; Galadosaghna, Kesya,Tvaccya, Stambhana, Raktasodhana
IMPORTANT FORMULATIONS – Nyagrodhidi Churna, Asanavilvidi Taila
THERAPEUTIC USES – Krimiroga(Antihelmenthic), Kushtha, Prameha, Pin•u, Medodosha
DOSE – 50-100 g of the drug for decoction.