The Purification Of Chlorogenic Acid Extract From Eucommia Ulmoides Oliv Leaves And The Research Of Chlorogenic Acid’s Inhibiting Effect To Bacterium

The main objectives of this study were to determine the purification process of chlorogenicacid in eucommia leaves, and the quality control was conducked through a fingerprint for qurifyproducts, then study the effect of the chlorogenic acid which is purified in eucommia leaves oninhibiting common bacterium in vitro, eg. Escherichia coli, Staphylococcus aureus,Streptococcus uberis, Streptococcus dysgalactiae, Bacillus cereus and Staphylococcust. and toprovide the experimental basis for clinical application. Macroporous adsorption resin was used topurify the chlorogenic acid in Eucommia leaves, the sample pretreatment was conducted byflocculating settling and then establish a fingerprint of chlorogenic acid with HPLC. Afterwards,UV spectrophotometry and HPLC were used to determine the quantity of chlorogenic acid. Theeffect of purified chlorogenic acid on inhibiting bacterium and the MIC was detected withfiltering paper and continuous gradient dilution.The result showed that the optimal conditions of precipitation were that add1ml1%chitosanacetate solution to10ml samples with pH=5, and whisk for4min at60℃, then put it in4℃for4hours, and a high degree of clarity of the sample solution was obtained after filtration. The bestprocessing parameters for separating and purifying chlorogenic acid from eucommia leavesextracts by NKA-Ⅱresin were as follows sample concentration:4g/L, sample volume3.5BV,pH=4, sample flow rate2BV/h, elution ethanol concentration70%, elution volume2BV, andelution flow rate2BV/h. And the result of the antibiotic experiment in vitro was that theStaphylococcus aureus was hypersensitive to the purified chlorogenic acid, and the other5bacteria were moderately susceptible, the MIC of3.58mg/mL chlorogenic acid againstEscherichia coli, Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae andBacillus cereus were0.25g/mL, and the MIC against Bacillus cereus and Staphylococcust were0.5g/mL with the quantity of chlorogenic acid was7.20mg/mL, in addition, the inhibition zonediameters of6bacterium were13.44mm,18.12mm,13.66mm,13.00mm,13.56mm and14.00mm respectively. The control of its fingerprint similarity with each batch of samples weregreater than0.9through similarity analysis, it indicated that the control fingerprint can representthe common characteristics of10batches of samples, and can be used as fingerprint ofchlorogenic acid separation and purification from Eucommia leaf in this study. In summary, the combination of flocculent settling and macroporous resin can be effectivelyused in isolating and purifing the chlorogenic acid from Eucommia leaf. The purifiedchlorogenic acid can be quality control through a fingerprint. And the purified chlorogenic acidhas antibacterial effect on Escherichia coli, Staphylococcus aureus, Streptococcus uberis,Streptococcus dysgalactiae, Bacillus cereus and Staphylococcust.