The Extraction Technique of Mixed Amino Acids from Hibiscus Syriacus L. Leaves

Using hydrochloric acid and ethanol solution as extraction reagents,the mixed amino acids in Hibiscus syriacus L.leaves were extracted through acid hydrolysis method and ultrasonic extraction,respectively.The extraction conditions were optimized.The results show that the optimum extraction conditions obtained are as follows: using acid hydrolysis method,the ratio of liquid to solid of 25 ∶1,hydrochloric acid of 6 mol/L,temperature of 100℃,extraction time of 5 h and extraction of 3 times,the extraction rate can reach 16.76% and the yield of amino acids can reach 8.9%;using ultrasonic extraction method,alcohol volume fraction of 80%,extraction time of 30 min,extraction of 3 times,the extraction rate can reach 17.42%,and the yield of amino acids can reach 8.93%.