Researching on extracting the hydroxycitric acid in fruit rinds of Garcinia Oblongifolia Champ. Ex benth in Vietnam

Abstract

This paper introduces research results of choosing method, time and zone of picking raw materials in order to extract (-)-hydroxycitric acid in fruit rinds of Garcinia oblongifolia Champ. Ex Benth most effectively. The results show that the content of hydroxycitric acid found with Soxhlet method in 8 h is acetone (13,06%), methanol (9,59%) extracted from 10 g of dried rinds with 200mL of water for 90 min under 1,2 atm pressure (15,25%). However, it only takes 25 ms to extract the same amount of HCA from 10 g of dried rinds with 150 mL of water using 400W microwave power (15,42%). The best time of picking raw materials is around 8 weeks since Garcinia oblongifolia Champ. Ex Benth has flowers. The content of (-)-hydroxycitric acid found by extraction with water using microwave does not depend on the zone of picking raw materials. This is the first finding on extraction of (-)-HCA from dried rinds of G. oblongifolia using microwave. It reduces time of extraction to 25 min and gives higher capacity compared with other methods.