Impact Of Sulfur Fumigation On The Quality Of Moutan Cortex And Its Preparations

Sulfur-fumigation has been used by herbal farmers and wholesellers during post-harvest handling of Chinese medicinal herbs.In this study,the effects of sulfur-fumigation on the quality of Chinese herbal medicines,including herbal raw materials,traditional Chinese medicine(TCM)decoctions and Chinese traditional patent medicine were investigated,taking Moutan Cortex(MC),Xi-Jiao-Di-Huang-Tang(XJDHT)decoction and Liu-Wei-Di-Huang-Wan(LWDHW)pill as examples,which includes the following 6 parts:1.Over views on altered chemistry/pharmacology/toxicology and inspecting methods of sulfur-fumigated herbs.In this part,sulfur-fumigation induced qualitative and quantitative alterations of bioactive components,and subsequent potential pharmacological and toxicological effects,as well as the current inspecting methods for sulfur-fumigated herbs were reviewed and discussed.Systemic investigation on the effects of different extention of sulfur-fumigation on the holistic quality of sulfur-fumigated herbs and their related preparations by modern analytical methods was recommended,and more rapid and specific inspecting methods for sulfur-fumgated herbs and related patent medicines were expected.2.Qualitative comparison of sulfur fumigation on MCFirstly,UPLC-QTOF-MS/MS method was developed to characterize the components in MC.A total of 42 components,including 11 monoterpenes and their glycosides,9 gallate glycosides,6 phenol ketones,4 flavonoids and two other types were identified or tentatively assigned.Among them,three sulfur-containing compounds,paeoniflorin sulfonate,oxypaeoniflorin sulfonate and benzoylpaeoniflorin sulfonate,were assumed to be induced by sulfur-fumigation.Secondly,UPLC-QTOF-MS/MS based metabolomics method was established to rapidly find out characteristic chemical markers of sulfur-fumigated MC(S-MC).Semi-quantitative method was used to quantify chemical markers and its precursor compound,and to correlate their contents and time extention of sulfur-fumigation.It was found that sulfur-fumigation can induce pinane monoterpene glycosides converted to its corresponding sulfur-containing derivatives,which has significantly affected the overall quality of MC.Sulfur-containing ion m/z 259 could be used as the diagnostic ion to screen pinane monoterpene glucoside sulfonates in S-MC.This approach is more rapid and specific than those previously reported.3.Quantitative comparison of sulfur fumigation on MCA simulating multiple reaction monitoring(MRM)method based on UPLC-QTOF-MS/MS extracting ion was newly developed to quantify multi-components of MC.The simulated MRM mode was confirmed to be better than full scan mode and UV detection mode in terms of linearity,sensitivity and specificity.With the established method,the effects of sulfur-fumigation on MC were quantitatively evaluated.It was found that sulfur-fumigation could differentially affect the quantity among components of different chemical types.4.Influence of sulfur fumigation on the quality of MC-containing preparationsUPLC-QTOF-MS/MS based metabolomics method was established to investigate the effects of S-MC with different sulfur-fumigation extend on the quality of XJDHT decoction,an MC-containing preparation.Decoction pH,PCA of small molecules,semi-quantitation of main ingredients and type of sulfur-containing derivatives were compared.Results indicated that even using qualified S-MC(sulfur dioxide residue less than 150 mg·kg-1),paeoniflorin sulfate was still detectable in XJDHT decoction.In other words,sulfur-fumigation could affect the quality of MC containing XJDHT decoction.5.Sulfur-containing derivatives as characteristic chemical markers in quality control of S-MCSulfur-containing derivatives in S-MC were confirmed by UPLC-QTOF-MS/MS analysis,and the contents of sulfur-containing derivatives and sulfur dioxide residues were statistically analyzed both in self-made and commercially available S-MC and MC as well as the samples thereof before and after eight-month storage.The amount of sulfur dioxide significantly decreased,but that of the newly-generated sulfur-containing markers did not,after eight-month storage of the S-MC samples,indicating that the amount of sulfur dioxide residue may not be positively correlated with the quality of S-MC.Sulfur-containing derivatives detection based method should be developed supplemented to sulfur dioxide residue determination for the quality control of S-MC.6.Inpection of S-MC in MC-containing Chinese traditional patent medicine.MC is one of the constituted herbs of LWDHW pill.UPLC-QTOF-MS/MS and UPLC-PDA methods were developed and compared to inspect the S-MC in MC-containing Chinese traditional patent medicine,using LWDHW pill as an example.It was found that nine of ten batches of commercial LWDHW pill samples were detected to be positive to sulfur-containing derivatives.Furthetmore,the content of paeoniflorin sulfate should be useful as an index to judge the sulfur-fumigation extend of S-MC in LWDHW pill.