Study On The Antibacterial Enhancement Active Constituents From Sour Jujube Fruit Extract And Their Application

Among the important resources of wild fruit trees and medicinal plants in our country,Sour jujube（Ziziphus jujuba Mill.var.spinosa（Bunge）Hu ex H.F.Chow）is an important part and has great development and utilization potential.The active components of wild jujube fruit have a variety of biological functions such as calming hypnosis,anti-tumor,anti-bacterial,anti-oxidation,and cellular immunity.Our previous study found that the chloroform extract of wild jujube fruit has antibacterial and sensitizing activity,and the active extract Fr.2a was further obtained after activity tracking column chromatography separation and purification.It was found that Fr.2a combined with a variety of antibiotics showed a wide range of synergistic antibacterial effects.Preliminary analysis by GC-MS showed that Fr.2a is composed of 15compounds^[1].In order to further analyze which compound monomers in Fr.2a are responsible for its antibacterial sensitization effect,this study screened the antibacterial sensitization activity of these 15 compounds and explored their mechanism of action.On the basis of Fr.2a,this study also used silica gel column chromatography to separate and purify the active ingredients in the chloroform extract of Jujube fruit in other polar ranges to obtain the refined Fr.B.The composition analysis,antibacterial sensitization activity analysis and antibacterial sensitization mechanism of the refined Fr.B were carried out.The refined Fr.B was prepared into an ointment,and the sensitization effect of the ointment on antibiotics was evaluated in vivo and in vitro.This study provided new ideas and solutions for overcoming antibiotic resistance.1.The activity screening of the compounds in Fr.2a,among which the compounds1,1-dichloromethyl ether and 1,3-dichloropropanol both have good antibacterial activity,but do not have sensitizing activity;the compound oleic acid amide alone does not have antibacterial activity,but when used in combination with ampicillin（Amp）,it can significantly enhance its inhibitory effect on Pseudomonas aeruginosa.We further explored its mechanism of action,the results showed that oleic acid amide does not enhance the antibacterial activity of Amp against Pseudomonas aeruginosa by interfering with the formation of biofilms or inhibiting the activity and expression ofβ-lactamase.2.This study also used silica gel column chromatography combined with activity tracking to separate and purify the active components in the chloroform extract of Jujube in other polar ranges.The separated Fr.B is determined to be the refined product with antibacterial sensitization activity.The Fr.B component obtained through GC-MS,IR chromatography,NMR analysis,its main components:30.07%elaidic acid,24.08%oleic acid,11.54%cis-10-hexadecenol,10.54%palmitic acid,3.97%1-tetracosene,2.89%petroselinic acid,2.12%cis-11-octadecenoic acid,2.08%trans-13-octadecenoic acid,2.06%cis,cis-13,16 docosadienoic acid,1.96%pentadecane,1.36%linoleic acid,1.08%methyl linoleate,1.07%cis-11-eicosenoic acid,1.05%erucic acid,0.98%cis-13-octadecenal,0.85%trans-9-octadecenoic acid methyl ester,0.64%cis-11eicosenoic acid,0.32%cis-9-tetradecene-1-alcohol acetate,0.32%cis,cis-9,12-hexadecadienoic acid,0.12%1-palmitate monoglyceride,0.07%1-tridecene,0.05%13-methyl tetradecanoic acid methyl ester,0.05%hexanoic acid,0.03%2-aminobutyric acid,0.02%heptanoic acid and so on.3.The antibacterial sensitization activity of the refined Fr.B was studied,and the results showed that Fr.B exhibits a wide range of synergistic antibacterial effects when combined with a variety of antibiotics,and can be combined with antibiotics to inhibit the growth of MRSA and Candida albicans.The antibacterial sensitization mechanism of Fr.B is to enhance the antibacterial effect of antibiotics on bacteria by changing the permeability of cells.4.Ointment prepared with Fr.B and 1%Em as main raw materials（named as Kang ba）.The therapeutic effect of Kangba ointment was evaluated by measuring the wound diameter and the colony situation in the wound of mice under different treatments.Compared with erythromycin ointment,Kangba ointment has a better therapeutic effect on wound infections caused by MRSA,suggesting that it has a good clinical application prospect.This study will provide a theoretical basis for solving antibiotic resistance,and is expected to lay the foundation for the development of new antibacterial sensitizers,and at the same time expand the application of the functional components of wild jujube fruit in the treatment of wound infections.