Studies on the alkaloid contents of the bark of Cinchona found in Sri Lanka

Studies on Cinchona carried out in our laboratory indicated that the extraction of bark with benzene - ethanol (1 :1) mixture gave the highest yield of alkaloids. The optimum time of extraction required to obtain the maximum content of alkaloids was found to be 16 hours. The survey of existing Cinchona trees in the country indicated that quite a large number of trees are still existing in the jungles of the tea estates in a neglected state. The alkaloid contents of the samples collected from these plants varied very widely, the highest alkaloid contents were found in plants growing in high elevations. The two dimensional thin layer chromatographic technique devised in our laboratory was used to study the distribution of alkaloids in the bark samples.