Changes Of Small Molecular Sugars And Their Effects On Intestinal Bacteria Before And After Fermentation Of Winter Jujube In Vitro

Winter jujube has a long history of cultivation in China.It is popular with people because of its thin skin,thick flesh,juicy pulp and sweet taste.It is a high-quality fresh-eating jujube variety in China.Dongzao jujube is rich in carbohydrates,vitamins and minerals and other nutrients.It also contains amino acids,cyclic adenosine phosphate(cAMP),flavonoids,carbohydrates and other active ingredients.Winter jujube is mainly eaten fresh,with fewer kinds of processed products.Because it is not easy to store and deteriorate,some winter jujube is surplus because of poor quality and less demand.Therefore,further processing or further research and development of winter jujube are carried out to make full use of it so as to reduce economic losses and enhance the economic value of winter jujube industry.It’s particularly important.In order to provide theoretical support for the development of functional food of jujube,this paper studied the effect of small molecule sugar of winter jujube on intestinal bacteria by simple in vitro experiments and in vitro simulation experiments.The main contents of this paper are as follows:1.The raw and small molecule sugars of winter jujube and fermented winter jujube were prepared by experiments.The technological parameters were as follows: ratio of material to liquid 1:3,extraction time 3 h,extraction temperature 80 C,yeast addition 1%,fermentation temperature 37 C,fermentation time 8 h.Two kinds of crude and small molecule sugar were purified by DEAE-52 and Sephadex-G15,respectively.Unfermented small molecule sugar(WDT)and fermented small molecule sugar(FDT)were obtained.2.The types and contents of monosaccharides in two kinds of small molecule sugar of winter jujube were determined by high performance liquid chromatography(HPLC).It was found that fructose,glucose and sucrose were the main monosaccharide components in WDT.Compared with WDT,sucrose also appeared in FDT,and the content of sucrose increased by25.1%.It was found that sucrose trisaccharide was produced by decomposition of sucrose during fermentation,and no sucrose was found in activated yeast powder solution.Therefore,sucrose trisaccharide was determined to come from decomposition of sucrose in Jujube Syrup rather than yeast.3.To study the effect of two kinds of small molecule sugar of winter jujube on bacterial growth in vitro,WDT and FDT were added to the corresponding liquid medium of Bacillus subtilis,Lactobacillus,Escherichia coli and Listeria,and OD values of four kinds of bacteria at the optimum observation time were determined by turbidimetry.The results showed that the addition of 0.1%-0.9% and 1%-5% WDT and FDT promoted the growth of Bacillus subtilis and Lactobacillus lactis(P < 0.05),0.1%-0.9% and 1%-5% WDT and FDT inhibited Escherichia coli(P < 0.05),0.1%-0.9% and 1%-3% WDT inhibited Listeria,and 4%-5%WDT promoted Listeria.However,there was no significant difference(P > 0.05).Addition of0.1%-0.9% and 1%-3% FDT had significant inhibitory effect on Listeria(P < 0.05),and 4%-5% FDT had promotive effect on Listeria(P < 0.05).WDT and FDT can promote or inhibit the growth of four kinds of bacteria.The average growth rate of FDT on Bacillus subtilis is 42.07%,which is higher than 41.41% of WDT at the same dose.The promotion rate of FDT on Lactobacillus is basically the same.The average inhibition rates of FDT on E.coli and Listeria were 12.56% and 18.56% respectively,which were higher than 11.39% and 15.84% of WDT of the same dose.On the whole,the promotion or inhibition effects of FDT on four kinds of bacteria were better than that of WDT of the same dose.4.To study the effect of small molecule sugar of Dongzao on intestinal bacteria in vitro.The digestive chyle and the fecal bacterial fluid of healthy volunteers were added to the prepared special culture medium after simulated gastrointestinal digestion of small molecule sugar in vitro,and then cultured in anaerobic workstation.The samples after culture were sequenced by 16 Sr DNA to analyze the effect of small molecule sugar of winter jujube on intestinal bacteria.The results showed that the composition and content of different phyla species changed at gate level,and there was no significant difference between WC group and FC group(P > 0.05),but there was significant difference between WC group and other three groups(P < 0.05),and there was also significant difference between groups at subject and family level.In addition to significant differences between groups,it was also found that the small molecule sugar of Dongzao had inhibitory effect on pathogenic intestinal bacteria Escherichia coli-Shigella,Shigella dysenteriae(P < 0.05),which indicated that the small molecule sugar of Dongzao had certain inhibitory effect on harmful bacteria in intestinal tract.