ABSTRACT:
This study investigate the use of ultrasound assisted extraction (UAE), the present work describes the application of ultrasound to improves the extraction efficiency of the classical solvent extraction techniques such as maceration and soxhelt extraction to extract various bioactive compound from natural source like plant and animals. In this review extraction of various compounds i.e.ß carotene, flavonoids, anthraquinones, isoflavones, cepharanthine, melanin, ursolic acid, from various plants i.e. morinda citrifolia, mitragyna speciosa, oscimum sanctum, polygonum cuspidatum, auricularia auricula, stephania rotunda lour,iris tectorum maxim, heterophyllaea pustulata hook, hawthorn seed, spirulina platensisand their therapeutic acivities like anti-inflammatory, anti-cancer, anti-oxidant, cardioprotective action, immunomodulatory, anti-diabetic, anti-rheumatic, anti-bacterial, anthelmintic, anti-depressant, hepatoprotective, radioprotective properties was extracted at different temperature 25o, 45o, 90o C, power setting 3, 6, 9 types of solvent used like ethanol methanol, acetone, acetonitrile in different composition and time 15, 30, 45, 60, 90 minute. The effect of various factors such as extraction solvent, solvent concentration, temperature, solvent to solid ratio, ultrasound power, extraction time, and particle size, on the yield of target components were investigated. Under the optimum conditions the extraction process is carried out and the yield obtained with UAE has been compared with batch and soxhelt extraction the result indicated that UAE was an alternative method for extraction. UAE is based upon acoustic cavitation. Cavitation produces physical effects such as liquid circulation currents and turbulence which results in significant increase in the mass transfer rates and thus increased extraction yield. To achieve the same recovery as that achieved by UAE, soxhelt extraction and maceration extraction required much longer time.