| Broccoli belongs to the cruciferous family and contains a variety of bioactive substances.Among them,sulforaphane(SFN)is extremely abundant in broccoli seeds and sprouts and has various physiological activities such as antioxidant,anti-inflammatory,anti-cancer and improving the microbial structure of the intestine.SFN can prevent chronic diseases such as non-alcoholic fatty liver,diabetes and obesity.In this study,high purity SFN was first extracted and purified from broccoli seeds.Secondly,broccoli sprouts with high SFN content were obtaine d by spraying exogenous trehalose-6-phosphate(T6P).Finally,a bionic gastrointestinal reactor was used to ferment the feces of obese patients in vitro t o study the effect of SFN on the intestinal microorganisms of obese pati ents.The following conclusions were obtained from this study :(1)The single-factor optimization of extraction conditions revealed that the enzymolysis temperature and enzymolysis p H had a significant effect on the extraction amount of SFN.Based on the single-factor analysis,orthogonal optimization test was carri ed out to obtain the optimal extraction conditions: the enzymolysis time of 12 h,the enzymolysis p H of 7,the enzymolysis material liquid ratio of 1:4,and the enzymolysis temperature of 30℃.Under these conditions,the extraction amount of SFN could reac h 6.71 mg/g.The crude SFN was purified by semi-preparative liquid chromatography,and the purity of the obtained SFN could reach 95%.Finally,the purified SFN was identified by liquid chro matography-mass spectrometry(LC-MS),and the extract was confirme d as SFN.(2)By measuring the content of SFN in broccoli sprouts,it w as found that the optimal spraying concentration o f trehalose-6-phosphate(T6P)was 500 μM,and the SFN content increased by 91%.T6 P at 500 μM significantly increased the growth index(plant height and fresh weight),tot al glucosinolates conten t and myrosinase activity,as well as the content of free amino acids(methioni ne and tryptophan),hormones(Jasmonic acid and Jasmonic acid-isoleucine),total phenols and flavonoids in broccoli sprouts.By fluorescence quanti tative PCR analysis,exogenous spraying of T6 P was found to significantly up-regulate the expression of genes related to SFN synthesis such as MYB28,SUR1,UGT74B1,CYP79F1,CYP83A1 and SOT18.(3)SFN was not degraded after simulated digestion by saliva,gastric juice and small intestinal fluid,indicating that it could be safely delivered to the colon.In vitro ferment ation showed that,SFN could increase the content of the intestinal metabolites Short-chain fatty acid(SCFAs),by 21% and 46% increase in butyric acid and valeric a cid,respectively.By 16 S r DNA gene sequencing ana lysis,SFN was found to increase the dive rsity of intestinal microorganisms.Meanwhile,SFN could increase the abundan ce of a variety of beneficial intestinal flora,including Weissella,Leuconostoc,Lactobacillus,Algiphilus and Faecalibacterium,and inhibit the abundance of harmful bacteria,su ch as Klebsiella,Escherichia-Shigella,Clostridium＿sensu＿stricto＿1,Sutterella,Megamonas and Proteus. |
