Study Glycyrrhetinic Acid Derivatives And Screening Of Biological Activity

Taking licorice as the mainly research object, This study measured content of amino acids and regulated blood sugar level. Finally this study Modified structure of glycyrrhetinic acid and determinated its biological activity.(1) The determination of amino acid content in glycyrrhiza phenylisothiocyanate(PITC) was the pre-column derivation reagent and the content of amino acids was determined with RP-HPLC method. Results: The 21 amino acids had good linearity in the range of 0.0019-2.7000μmol/L. The RSD of precision was between 0.38% and 1.05%; the repeatability was between 0.46% and 1.28%. Free and hydrolysis amino acids of the stability was between 0.32% and1.68%; the sample recovery rate was between 97.89 % and 101.05% and between 98.04 % and 103.03%, and the RSD was less than 4%.The content of free amino acid and hydrolytic amino acid was 0.1297% and 0.3285.(2) Active research of fall blood sugar of liquorice ethanol extract This study results shown that the liquorice ethanol extract could reduce the serum glycosylated hemoglobin, low density lipoprotein, triglyceride, total cholesterol, and improve their oral glucose tolerance and elevated serum insulin levels to reduce the blood sugar of diabetic mice. Licorice ethanol extract ccould improve the level of MDA, reduce the activity of SOD and GSH. Above all licorice ethanol extracts had the function of the fall blood sugar, and had antioxidant activity.(3) By the principle of esterification reaction by EDCI and DMAP respectively glycyrrhetinic acid with isopropyl alcohol, dithiothreitol, isoamyl alcohol, propylene glycol, benzoic acid and malonic acid, sorbic acid, phenylalanine, glycine, leucine, and so on has carried on the esterification, eventually got 27 derivatives, then the derivative structure are defined by13CNMR、1HNMR and IR.(4) 27 kinds of glycyrrhetinic acid derivatives of activity screening in vitro Using HPLC method and colorimetric method of 27 kinds of derivatives of biological activity screening, this results shown that the inhibition of glycosidase activity, the derivatives of benzoic acid synthesis by the inhibition effect was best. For nitrite scavenging effect, derivativesformed by glycyrrhetinic acid and the small molecules of saturated aliphatic alcohols of the nitrite scavenging effect was higher than itself, derivativesformed by glycyrrhetinic acid and n-butyl alcohol of clearing effect was best. For the inhibition of AChE, 30 into the glycyrrhetinic acid ester derivatives has no inhibition, derivativesformed byglycyrrhetinic acid, p-hydroxy benzoic acid, lipoic acid and benzoic acid and sorbic acid of ACE inhibitory effect was also obvious, especially the sorbic acid.For the inhibition of ACE, compared with glycyrrhetinic acid, the amino acid derivatives of the inhibition of ACE inhibitory effect were good.For the inhibition of HMG- CoA, derivatives formed by glycyrrhetinic acid and benzoic acid was best.