Distribution of progestogenic proanthocyanidins within the inflorescence of Cocos nucifera L.
Padumadasa C, Dharmadana D and Abeysekera AM
In Sri Lanka, the immature inflorescence of Cocos nucifera L. is used by Ayurvedic and traditional medical practitioners for the treatment of menorrhagia. We have previously reported that the inflorescence of Cocos nucifera L. predominantly contains proanthocyanidins. In addition, the progestogenic activity of ethyl acetate soluble proanthocyanidins of Cocos nucifera L. inflorescence has also been reported in relation to its ethnomedical usage. Cocos nucifera L. inflorescences at different maturity stages were used to determine the variation of the yield of ethyl acetate soluble proanthocyanidins (EASPA) and aqueous soluble proanthocyanidins (AQSPA) with maturity. In addition, variation of proanthocyanidin content of the inflorescence along the length of the inflorescence at different maturity stages and proanthocyanidin content of different floral parts of the inflorescence were determined by the acid butanol assay. The percentage yield of crude EASPA decreases, whereas percentage yield of crude AQSPA increases, with increasing maturity of the inflorescence. In all stages of development, the middle section of the inflorescence contained the highest level of proanthocyanidins. The female flower has higher proanthocyanidin content than any other floral part of the inflorescence. The current Ayurvedic and traditional medical practice of using the total immature inflorescence just prior to opening appears to optimize the procedure for obtaining an adequate concentration of EASPA (which has been shown to contain progestogenic activity) for therapeutic purposes. Thus, our studies do not indicate the need to change the current Ayurvedic and traditional medical practice of the use of total immature inflorescence just prior to opening for the treatment of menorrhagia.