Determination of Tolerable Dose of Litchi Fruit Considering Reported Hypoglycin A And MCPG Contents through Biochemical and Histopathological Evaluations in Mice

Litchi fruit has recently been reported to be associat-ed with encephalopathy outbreaks in India due to presence of hypoglycaemic phytotoxins, hypoglycin A (HGA) and methylenecyclopropyl-glycine (MCPG). Therefore, a need was felt to determine safe tolerable dose of fruit based upon animal feeding studies. Swiss albino female mice (in each group, n = 6) were fed in both starved and unstarved conditions with maximum possible quantity of litchi pulp within 10 h duration at 2.5 h intervals (total quantity ~16 g). This did not re-sult in hypoglycaemia, weight loss or changes in be-haviour. Haematology profile, liver and kidney functions remain unchanged. Histopathological analy-sis of brain, liver and kidney too did not indicate any structural changes. From the reported range of above toxins in litchi pulp the quantity fed corresponds to the cumulative minimum concentration of 2.48 and ~9.0 mg/kg body weight of mice for HGA and MCPG respectively, which is lesser than LD₅₀ values of these toxins, i.e. 90–100 mg/kg body weight reported in rat. Thus based upon equivalent dose-quantity conversion, approx. 3.9 kg of litchi pulp/day for an adult human (weighing 60 kg) and 0.59–1.17 kg of pulp/day for children (1–5 years of age respectively) could be con-sidered a safe quantity.