Study On Alleviation Effect Of Jujube Polyphenol Extract On DSS-induced Ulcerative Colitis In Mice

Jujube(Ziziphus Jujuba Mill.),a rhamnaceae plant,has a long planting history in China and is widely planted in Ningxia.Its fruit is round and full,sweet and nutritious,and it is very popular among people.Jujube contains a variety of nutritional components and bioactive substances,among which phenolic compounds show important functional activities in antioxidant and anti-inflammatory.Ulcerative colitis is a kind of inflammatory bowel disease,and polyphenols have certain antioxidant and anti-inflammatory effects on it.However,at present,there is little research on the relieving effect of jujube polyphenols on colitis,and its mechanism is still unclear.In this paper,jujube polyphenol extract was obtained by ultrasonic-assisted method.The main components of jujube polyphenol extract were identified by UPLCQ-Exactive MS LC-MS,and its antioxidant activity was studied.To establish an animal model of ulcerative colitis C57 mice induced by DSS,study the anti-inflammatory effect of jujube polyphenol extract on ulcerative colitis mice,and clarify its relieving mechanism.The main research contents and results are as follows:(1)Optimization of extraction technology,analysis of components and antioxidant activity of jujube polyphenols.Ultrasonic-assisted extraction was used to extract phenolic compounds from jujube,and single factor experiments were carried out by selecting methanol concentration,ultrasonic time,ultrasonic temperature and solid-liquid ratio.On this basis,response surface methodology was used to optimize process parameters.At the same time,UPLC-Q-Exactive MS liquid chromatography-mass spectrometry(LC-MS)was used to determine the components of jujube polyphenols,and the antioxidant activity of jujube polyphenols was evaluated by scavenging 1,1-diphenyl-2-trinitrophenylhydrazine free radical and superoxide anion free radical.The results showed that the optimum technological parameters of ultrasonic-assisted extraction of polyphenol from jujube were as follows:methanol concentration 70%,ultrasonic time 40 min,ultrasonic temperature 60℃,and solid-liquid ratio 1:40(g/mL).Under these conditions,the polyphenol yield was 1.397%±0.08%.The determination results of polyphenol extract of jujube showed that there were 28 components,including phenolic acid and its derivatives,flavonoids,reticular annonacine,linderaine,stilbene,lignan,triterpene acid,benzoic acid and phenylpropionic acid.The results of antioxidant experiment showed that the scavenging rate of jujube polyphenol to 1,1diphenyl-2-trinitrophenylhydrazine free radical was 77.63%±1.65%at the concentration of 0.3 mg/mL,and the scavenging rate of jujube polyphenol to superoxide anion free radical was 82.48%±2.37%at the concentration of 1.0 mg/mL,and the scavenging capacity was close to Vc with the increase of polyphenol concentration,which indicated that the scavenging rate was close to Vc.(2)The relieving effect of jujube polyphenol extract on DSS-induced ulcerative colitis in mice.The animal model of ulcerative colitis induced by DSS was established,and 200 mg/kg of j ujube polyphenol extract was administered by stomach for one week.The related physiological indexes and intestinal mucosal morphology of mice were detected to explore the relieving effect of jujube polyphenol extract on colitis.The results showed that jujube polyphenol extract could reduce the DAI score of colitis mice,alleviate the weight loss of mice,improve the diet and water consumption of mice,reduce the damaged integrity of ileum wall of colitis mice,and increase the number of goblet cells and mucin in colon tissue.To sum up,the polyphenol extract of jujube has a certain relieving effect on ulcerative colitis.(3)The study of Jujube polyphenol extracts to relieve the study of DSS-induced ulcerative colitis through MAPKS/NLRP3 pathway.The inflammatory factor-related inflammatory factors of mice were detected through the RT-PCR detection method.At the same time,the protein immunohic traction method was used to detect NLRP3 inflammatory small body pathway related proteins(NLRP3,CASPASE-1,IL1β,etc.)and MAPKS pathin(P-Change of P38,P-ERK,P-JNNK).Results show that red dates polyphenol extract can reduce inflammation factors(IL-1β,NLRP3,TLR4,TNF-α,IL-8,IL-12,IFN-γ,etc.),and can restore protein that is regulated by DSS.The level makes it close to normal values.Explain that red dates polyphenol extract can relieve the DSS-induced mouse ulcerative colitis through the MAPKs/NLRP3 pathway.