Research On The Quality Evaluation Of Morus Alba Based On Chemical Components

Mori Cortex is the dried root bark of Morus alba L..It is cold and sweet in nature and attributed to the lung meridian with the effect of removing heat from lung,relieving asthma and inducing diuresis for removing edema.It is a traditional TCM that used to treat a series of disease,such as dyspnea and hyperactivity cough due to the lung-heat,edema,oliguria and facial edema.Mori Cortex was the firstly recorded in Sheng Nong’s herbal classic.Although the rough bark of Mori Cortex should be peeled before using in many medicine books and Chinese pharmacopoeia.Mori cortex with rough bark is still sold in the market.Meanwhile the root bark of Cudrania tricuspidata(Carr.)Bur.and Paper Mulberry is used as Mori cortex alternative.Is there a difference in chemical composition between peeling and unpeeling Mori Cortex? Can the root bark of them be a substitute for the Mori Cortex? However,the quality control of Mori Cortex only includes morphological characters,differentials(Powder microscopic characteristics and TLC)without determination of content.This research established a high-performance liquid chromatography-mass spectrometry(HPLC-MS)method for analyzing the chemical compounds in Mori Cortex,compared the effects of peeling process on chemical composition and explored the differences of chemical constituents between Mori Cortex and its adulterants.HPLC method was developed for simultaneous determination of seven constituents Mulberroside A,chlorogenic acid,dihydromorin,oxyresveratrol,moracin O,kuwanon G and kuwanon H in Mori Cortex with bark and without bark.These results established a foundation for quality evaluation and further provided a reference for ensuring safe and effective clinical medication of Mori Cortex.The main results are as follows:1.The analysis of methanol extract of Mori Cortex with bark and without bark and its bark by HPLC-MS To identify the chemical constituents and compare the differences between Mori Cortex with and without the bark and its bark by HPLC-MS method.33 compounds were confirmed in total,including 8 Diels-Alder compounds,12 flavonoids,5 2-arylbenzofuran derivatives,4 stilbenes,3 coumarins and 1 phenolic acid.33 compounds were identified in Mori Cortex with bark,22 compounds in Mori Cortex without bark and 26 compounds in its bark.Compared Mori Cortex with bark and without bark,there were 22 kinds of compounds in common,11 different compounds,including kuwanon P,mulberrofuran G,kuwanon O,kuwanon K,kuwanon W,sanggenon G,cudraflavone C,sanggenol A,moracin 2-dimer,mulberrofuran Q,mulberrofuran B.compared Mori Cortex with bark and its bark,there were 26 kinds of compounds in common,7 different compounds,including 7-hydroxycoumarin-6-O-α-L-rhamnosyl-(1→6)-O-β-D-glucopyranoside,chlorogenic acid,resveratrol-2-O-β-D-glucopyranoside and its isomers,dihydromorin,moracin M,moracin O.2.Simultaneous determination of 7 components in Mori Cortex with and without bark by HPLC HPLC was performed to determine 7 components(mulberroside A,chlorogenic acid,dihydromorin,oxyresveratrol,moracin O,kuwanon G and kuwanon H).the average content of 7components in Mori Cortex with and without was respectively 17.3035,11.7739 mg/g;1.1105,0.6923 mg/g;0.6705,0.4363 mg/g;0.2977,0.5120 mg/g;0.1392,0.0729 mg/g;0.9315,4.8426mg/g;0.1552、1.3723 mg/g.Compared with the Mori Cortex with bark,the average content of mulberroside A,chlorogenic acid,dihydromorin and moracin O was increased 46.97%,60.41%,53.68% and 90.95%,while oxyresveratrol,kuwanon G and kuwanon H decreased 41.86%,80.78%and 88.69% after peeling process.3.The analysis of methanol extract of the root bark of Cudrania tricuspidata(Carr.)Bur.and Broussonetia papyrifera(L.)Vent.by HPLC-MS A HPLC-MS method was used to qualitatively analyze the chemical constituents of its adulterants,the root bark of Cudrania tricuspidata(Carr.)Bur.and Broussonetia papyrifera(L.)Vent..29 compounds were identified in total.There were 20 compounds in Cudrania tricuspidata(Carr.)Bur,including 13 flavonoids,5cudraxanthone,1 phenolic acid and 1 other compounds.There were 9 compounds in Broussonetia papyrifera(L.)Vent.,including 7 flavonoids,1 phenolic acid and 1 alkaloid.A comprehensive analysis was conducted on the HPLC-MS results,It showed that there was much difference in chemical compounds of the three plants.Cudraflavone C and moracin were the common constituents of the Mori Cortex and Cudrania tricuspidata(Carr.)Bur..Chlorogenic acid was the common constituents of the Mori Cortex and Broussonetia papyrifera(L.)Vent..4.Study on HPLC fingerprint of Mori Cortex and Its counterfeit and chemical pattern recognition The HPLC fingerprint of Mori Cortex was established and evaluated with similarity analysis.Statistic software SPSS was used to assess the samples by the methods of principal component and clustering analysis.10 common peaks were found in the HPLC fingerprint of Mori Cortex and 5 peaks was identified by the standards.The similarity analysis showed that similarity degree of 12 batches of Mori Cortex are higher than 0.922,which means the samples had good similarities and stable quality.The first three major principal components added to 78.005%.These results indicated that Mori Cortex and the its counterfeit(Broussonetia papyrifera(L.)Vent.,Cudrania tricuspidata(Carr.)Bur.)can be obviously divided into 2 clusters by PCA and CA.The method of HPLC fingerprint has good repeatability and specificity,which can provide a basis for quality control of Mori Cortex.