Acute Toxicity (LD50) Profile of Ethanol Extracts of Chia Seed (Salvia hispanica), Tiger Nut (Cyperus esculentus), and Their Combination in Wistar Rats

Abstract

Chia seed (Salvia hispanica) and tiger nut (Cyperus esculentus) are increasingly explored as plant-based dietary interventions for the management of diabetes mellitus, but data on the acute safety of their combined use remain scarce. This study evaluated the acute oral toxicity (LD50) of ethanol extracts of chia seed, tiger nut, and their combination in male Wistar rats using Lorke's method. Toxicity testing was conducted in two phases. In Phase I, rats (n = 3 per group) received oral doses of 10, 100, and 1000 mg/kg body weight of each extract and were observed for 24 hours. Since no mortality occurred in Phase I, Phase II was conducted using single rats per group administered higher doses of 1600, 2900, and 5000 mg/kg body weight, with observation extended to 72 hours. No deaths were recorded at any dose level for chia seed extract, tiger nut extract, or their combination, up to the highest tested dose of 5000 mg/kg body weight. Rats administered the highest dose (5000 mg/kg) of the chia seed extract and the combined extract appeared visibly weak, while those given tiger nut extract at the same dose appeared only slightly weak; no other overt behavioural or physical signs of toxicity were observed in any group. Since no lethal dose was established, a definitive LD50 value could not be computed, and the practical LD50 of all three extracts is therefore considered to exceed 5000 mg/kg body weight. These findings suggest that ethanol extracts of chia seed, tiger nut, and their combination are relatively safe for oral consumption at the doses tested and support their classification as practically non-toxic according to the Hodge and Sterner toxicity scale, providing a safety basis for their further pharmacological evaluation in the management of diabetes.