Phytochemical screening, elemental analysis and acute toxicity of aqueous extract of Allium sativum L. bulbs in experimental rabbits

Abstract

There seems to be little literature about the toxicity of the widely used garlic, which makes it important to investigate chemical elements as well as chemical compounds that could be present in garlic bulbs and their safety for human handlers and consumers. Phytochemical screening and elemental analysis of powdered bulb of Allium sativum L. and toxicological effects of its aqueous extract were investigated in experimental rabbits. Acute toxicity study was conducted following subcutaneous administration of graded doses of the plant extract in experimental rabbits. LD50 was found to be 3034 mg/kg and maximum tolerated dose was 2200 mg/kg. Mortality occurred in rabbits given the extract at 3200 and 4200 mg/kg with other behavioural signs like loss of appetite and partial paralysis. The percentage yield of the extract was 75.8%. Elemental analysis indicated that the powdered plant material contained mainly potassium, phosphorus and iron among other elements. While the phytochemical screening revealed presence of the following chemical compounds: saponins, steroids, tannins, carbohydrates and cardiac glycosides, whereas, alkaloids, cadenolide, flavonoid, anthraquinone and cyanogenic glycosides were found absent. Key words: Garlic, chemical elements, chemical compounds, safety margin, rabbits, Nigeria.