Inhibitory effect of bitter principle of palmyrah (Borassus flabellifer L) fruit pulp on the growth of mice: evidence using bitter and non-bitter fruit pulp

Abstract

Different cultivars of palmyrah produce mature fruits of differently flavoured palmyrah fruit pulp (PFP). A natural ‘sweet’ (non-bitter) variety exists. Bitter and naturally non-bitter palmyrah fruit pulps showed little difference in total sugars (471 and 543 g kg−1 respectively), estimated by the Nelson method after invertase action, and had total crude flabelliferin contents of 1480 and 1650 mg kg−1 respectively. The flabelliferin profiles on silica gel G60 TLC plates developed using butanol; ethanol; NH3 (7:2:5) differed. Bitter fruit pulp (from Jaffna) contained the bitter flabelliferin F-II as the major component (about 900 mg per kg), while the non-bitter fruit pulp (from Ampara) did not contain F-II but contained the anti-microbial flabelliferin, FB. Incorporation of non-bitter PFP at the 100 g kg−1 level into WHO standard mice-breeding feed resulted in significantly increased (p = 0.00008) weight gain by ICR mice compared with bitter PFP incorporation at the same level in the feed. Weight gain was also significantly higher (p = 0.021) than in the control (WHO standard mice-breeding feed). The study supports the conclusion that the bitter principle, F-II is responsible for reduced weight gain in mice. © 2000 Society of Chemical Industry