Research On The Determination Of Allicin

Garlic (Allium Sutivum L.) is a herb plant of the Alliaceae. Allicin. which is the main bacteriostatic substance of garlic, is reacted of alliin in the role of alliinase. The content of allicin is always used as one of the important indices for evaluating the effect of garlic. However, the allicin is so unstable and the standard sample is difficult to prepare. There is no good method for the determination of allicin now.Compared with other determination method of allicin, this research proposed the chromatography conditions and methods on determination of allicin by high performance liquid chromatography. The main results were as follows:1. Improving the mercury nitrate method on determination of allicin, the results showed that the best handling mode of ether is evaporating, and the best solvent is alcohol. Improving the fix-sulfur method on determination of allicin, use the ether to dispose garlic solution. The best dosage of nitric acid was4mL, the appropriate pH of test solution was about2.2. The method for alliin separation, purification and convertion were established. Use0.5mol/L ammonia to elute alliin, use10%(m/v) PEG8000to precipitate alliinase, the hydrolysis condition of allicin were:the temperature was35℃, the reaction time was0.5h, L-cysteine can inhibit the course of enzymatic reaction.3.Established the HPLC method on determination of allicin, the condition were: methanol:water=(9:1)(V/V), the flow rate was0.5mL/min, the detection wavelength was214nm, The alliin showed a good linear relationship at a range of4-128μg/mL, the average recovery was97.39%, RSD=1.5%(n=9), and the detection limit was0.247mg/kg.4. The average relative error showed that the precision of HPLC method was higher than the methods of fix-sulfur and mercury nitrate, and the fix-sulfur method and mercury nitrate method can be used on determination of allicin after adjusting by the HPLC method.