Study On 5-hydroxymethylfurfural And Other Physicochemical Indexes During Storage And Discoloration Of Traditional Chinese Medicine

1 Correlation between discoloration of Stemonae Radix and the contents of 5-hy-droxymethylfurfural(5-HMF)with various analytical techniquesTo explore the correlation between discoloration of Stemonae Radix and the con-tents of 5-HMF by various analytical techniques.Stemonae Radix is a commonly used expectorant and antitussive antiasthmatic medicine.The phenomenon of being oil-spill-ing is easily occurring during storage which can cause the discoloration.The appear-ances of Stemonae Radix were identified by traditional methods of viewing,tasting and touching.The value of L*,a*,b*of samples solution extracted by methanol/water(50:50,v/v)were detected by colorimeter.The colors of Stemonae Radix powder were deter-mined using IRIS visual analyzer.The component of 5-HMF was confirmed by Liquid Chromatography Mass Spectrometry(LC-MS).Signal to noise ratio in aldehyde region of methanol extract was analyzed by 1H-Nuclear Magnetic Resonance(1H-NMR).5-HMF contents were determined by HPLC.The correlation between the color of the Stemonae Radix and the contents of 5-HMF were analyzed by the method of bivariate correlation analysis and cluster analysis.3 oil-spilling samples and 1 sample of poor quality were identified from 12 sam-ples by traditional methods.The colors of oil-spilling samples were brown,dark brown and black.The texture was oil and sticky.With the color deepens,the brightness of the color of the solution turned dark,the value of L*was decreased and the value of a*was increased.The results of LC-MS showed the existence of 5-HMF.The 1H-NMR spectra were measured in CD3OD solution with the chemical shift values as ? in ppm.The peak of the chemical shift of 9.55 ppm in 1H-NMR is the aldehyde group in 5-HMF,and the Signal-to-Noise(S/N)ratio of the oil-spilling samples is significantly higher than other samples.The corresponding position of 5-HMF was determined in the chromatogram of HPLC by comparing with reference materials.A method for determination of 5-HMF contents by HPLC was established.The contents of 5-HMF in oil-spilling sam-ples were 0.779 0-4.623 mg·g-1 while 0.018 16-0.110 8 mg·g-1 in samples which were not oil-spilling.The statistical results showed that the contents of 5-HMF have negative correlation with the value of L*and positive correlation with the value of a*.The darker the brightness,the deeper the color,the higher the content of 5-HMF.Oil-spilling sam-ples were grouped into one category and others were grouped into another.Changes in color of Stemonae Radix were correlated to 5-HMF contents.The correlation between discoloration of Stemonae Radix and 5-HMF contents was confirmed by various analytical techniques.This provides a demonstration for the quality evaluation of other medicinal materials.2 Determination of 5-HMF contents in Chinese nedicinesTo analyze the correlation between 5-HMF contents and the color and storing-year of 12 Chinese medicines.12 Chinese Medicines include Schisandra Chinensis Fructus(SCF),Jujubae Fructus(JF),Longan Arillus(LA),Asparagi Radix(AR),Codonopsis Radix(CR),Crataegi Fructus(CF),Rehmanniae Radix(RR),Mori Fructus(MF),Si-raitiae Fructus(SF),Ophipopgonis Radix(OR),Medicated Leaven(ML),and Red Gin-seng(RG)were collected.The appearances of Chinese Medicines were observed by traditional methods.The contents of 5-HMF were determined by HPLC,and the corre-lation of color,storing-year and 5-HMF contents was analyzed.The color of SCF was red when stored for 1 year and then deepened to dark red or red brown when stored for 2 years.The average contents of SCF was 0.036 15 mg·g-1,5-HMF contents in SCF stored for 2 years were higher than that in SCF stored for 1 years.It showed that with the extension of storage time of SCF,the color gradually deepens and the content of 5-HMF increases.The average contents in Schisandra pro-cessed with vinegar(SPV)were 10.67 mg·g-1,which were higher than that in SCF.It shows that a large amount of 5-HMF is generated during the process of processing.The color of JF was red or dark red,while JF products were reddish brown or blackish brown.The contents of 5-HMF in JF products are significantly higher than those in JF.The storage of LA exists two forms,one is dried LA(dried fruits),the other is LA(aril).With the deepening of the color,the 5-HMF contents increase.The contents of 5-HMF in LA stored in dried fruits form did not increase obviously.It is advised to store LA in the form of dried fruits.The 5-HMF contents in AR,and CR increased with the color deepened.CF was divided into CF and fried CF.The color of CF was brown or yellow,the color of FCF was dark or brown.The average contents of 5-HMF in FCF were 4.48 times as many as the 5-HMF contents in CF.It shows that a large amount of 5-HMF was produced in fry process.The color of RR was brown or dark brown and the differ-ence between samples was not obvious.The contents of 5-HMF in RR were gradually increased in samples produced in 2014,2013 and 2010.The contents of 5-HMF in RR is related to storing-year.The color of MF samples was brown or blackish brown and the difference between samples was not obvious.The average contents of 5-HMF in samples produced in 2014 were 13.86 times more than samples produced in 2016,and the average content of 5-HMF in the samples produced in 2012 were 96.50 times as many as the average contents of 5-HMF in samples produced in 2016.The contents of 5-HMF is related to storing-year.Correlation of 5-HMF contents in SF,OR,ML,and RG and color and storing-year were not obvious.5-HMF contents in some Chinese medicines were correlated with color and stor-ing-year.3 Dynamic analysis of physicochemical indexes of different kinds of Chinese med-icines under two kinds of storage warehousesStorage of traditional Chinese medicine is an important part in the process from harvesting to clinical use.Many kinds of deterioration during storage would appear and affect the quality and then affect the clinical use.To explore the dynamic changes of the appearances,contents of water,5-HMF and other indicative components of differ-ent kinds of Chinese herbs stored in two kinds of storage warehouses.Rhizomatous Chinese Medicine[Achyranthis Bidentatae Radix(ABR),Polygoni Multiflori Radix(PMR),Angelicae Dahuricae Radix(ADR),Notoginseng Radix et Rhizoma(NRR)and its powder],herbs[Schizonepetae Herba(SH),Plantaginis Herba(PH)],fruits and seeds[Longan Arillus(LA),Lych Fructus(LF),Trichosanthis Fructus(TF)and its slices,Walnut and walnut kernel,]and flower medicine[Chrysanthemi Flos(CFs),Lonicerae Japonica Flos(LJF)]of Chinese medicinal plants were stored in sim-ple and cool warehouses.During the storage time of 3th,9th,15th,21st,27th and 33rd months,samples were taken from two warehouses and the appearances of Chinese Medicines were observed.Contents of water,5-HMF and other indicative components were determined.The dynamically changed rules were analyzed.The temperature and humidity in the simple warehouse change with the seasonal fluctuation,and the cool warehouse keeps the constant temperature and humidity envi?ronment of 3.5?5.0 and 65?75%RH.Appearances The phenomenon of discoloration appeared in ABR,PMR,ADR,LF,CFs,LJF stored in simple warehouse.Walnut and walnut kernel,TF,slices of TF stored in simple warehouse were damaged by worms.Walnut and walnut kernel in sim-ple warehouse were oil-spilling.The deterioration of other samples and sample stored in cool warehouse were not obvious.Water contents Water contents were high in ABR,LA,LF,TF and slices of TF and the lowest in walnut and walnut kernel.The water content fluctuated with the pro-longation of storage time.Components contents As the extension of storage time,the content of ?-ecdy-sone of ABR in both warehouses was gradually decreased and was lower than 0.030%ruled by China Pharmacopoeia when be stored up to 27 months.The content of 5-HMF of ABR in both warehouses was increased and was higher in simple warehouse than that in cool warehouse.The content of 2,3,5,4'-tetrahydroxystilbene-2-O-?-D-gluco-side and combined anthraquinones(calculated with physcion and emodin)increased in PMR in simple warehouse and both changed slightly stored in cool warehouse.5-HMF contents in LA were increased with the prolongation of storage time.The increase trend of 5-HMF content of LA was consistent with the change trend of temperature-integral.The contents of Lycium Barbarum Polysaccharide(LBP)in LF stored in both ware-house were decreased and below the standard of pharmacopoeia when stored up to 27 months.The content of chlorogenic acid and 3,5-O-dicaffeoylquinic acid in CFs stored in simple warehouse decreased,while changing slightly in CFs stored in cool ware-house.The contents of galuteolin in CFs stored in both simple and cool warehouses changed slightly.As the extension of storage time,the content of chlorogenic acid in-creased in LJF stored in both simple and cool warehouses.Changes of 5-HMF contents in TF and slices of TF,ginsenosides Rgi and Rbi and notoginsenoside Ri contents in NRR,volatile oil and pulegone contents in SH,plantamajoside contents in PH were not obvious.The storage time of ABR cannot longer than 24 months.Storage time of walnut and walnut kernel in simple warehouse cannot longer than 15 months.15 months at most of TF and slices of TF stored in simple warehouse.The storage time of LF in simple warehouse cannot longer than 27 months.