Ⅰ紅藻多糖降解菌廣泛存在于自然界中的一些微生物，它們通過產(chǎn)生特定的酶類分子，如紅藻多糖酶，能夠有效地降解紅藻多糖，可將多糖降解成不同聚合度的功能性寡糖，被認(rèn)為具有巨大的應(yīng)用潛力。本實(shí)驗(yàn)從br菌群（細(xì)基江蘺分離出來的菌群）和zh菌群（瓊枝分離出來的菌群）中分別分離出2個(gè)單菌株(YD1、TD2)，對2個(gè)單菌株進(jìn)行了鑒定，驗(yàn)證了兩單菌株具有多糖降解能力，研究了多糖降解菌的生長并探究了多糖降解菌酶活性優(yōu)化條件。主要研究結(jié)果如下：本實(shí)驗(yàn)從br菌群和zh菌群中分別分離出2個(gè)單菌株(YD1、TD2)，然后對2個(gè)單菌株進(jìn)行總DNA提取，并通過對16SrRNA序列進(jìn)行特異性擴(kuò)增，利用NCBI網(wǎng)站上的BLAST對得到的序列進(jìn)行了比較，鑒定YD1、YD2分別為哈維氏弧菌(Vibrioharveyi)和對蝦鹽單胞菌(Halomonaslitopenaei)。本研究按照DNS法測定多糖酶活力等方法，驗(yàn)證了YD1菌株和YD2菌株具有多糖降解能力。本實(shí)驗(yàn)研究多糖降解菌的生長情況，結(jié)果表明：在D培養(yǎng)基、30℃、100r/min的搖床振蕩培養(yǎng)條件下，接種后6-24h為哈維氏弧菌和對蝦鹽單胞菌的快速生長期為了提高多糖降解菌產(chǎn)多糖酶量，本實(shí)驗(yàn)對多糖降解菌產(chǎn)多糖酶的發(fā)酵條件(卡拉膠濃度、瓊脂粉濃度、溫度、鹽度和PH)進(jìn)行了優(yōu)化。結(jié)果表明：選擇0.25%、0.20‰卡拉膠分別作為YD1菌株和YD2菌株生產(chǎn)多糖酶的最佳發(fā)酵濃度；選擇0.20%、0.25%瓊脂粉作為YD1菌株和YD2菌株生產(chǎn)多糖酶的最佳發(fā)酵濃度；選擇35℃作為YD1和YD2菌株生產(chǎn)多糖酶的最佳發(fā)酵溫度；選擇30‰鹽度作為YD1菌株生產(chǎn)多糖酶的最佳發(fā)酵鹽度，選擇20‰、0‰、30‰鹽度分別作為YD2菌株生產(chǎn)多糖酶的最佳發(fā)酵鹽度；選擇PH值為7和8分別作為YD1菌株和YD2菌株生產(chǎn)多糖酶的最佳發(fā)酵PH值。綜上所述，br菌落和zh菌落中的YD1菌株和YD2菌株對多糖的降解效果較好，可大量開發(fā)應(yīng)用于市場。Redalgaepolysaccharidedegradationbacteriaarewidelyfoundinsomemicroorganismsinnature.Byproducingspecificenzymemolecules,suchasredalgaepolysaccharideenzymes,theycaneffectivelydegraderedalgaepolysaccharides,andcandegradepolysaccharidesintofunctionaloligosaccharideswithdifferentdegreesofpolymerization,whichisconsideredtohavegreatapplicationpotential.Inthisexperiment,twosinglestrains(YD1,TD2)wereisolatedfromthebrflora(thefloraisolatedfromtheXijiRiver)andthezhflora(thefloraisolatedbyQiongzhi).Twosinglestrainswereidentified,verifiedthatthetwosinglestrainshadpolysaccharidedegradationability,andstudiedthegrowthandexplorationofpolysaccharide-degradingbacteria.Theconditionsforoptimizingtheenzymeactivityofpolysaccharidedegradationbacteria.Themainresearchresultsareasfollows:Inthisexperiment,twosinglestrains(YD1,TD2)wereisolatedfromthebrandzhflora,andthenthetotalDNAofthetwosinglestrainswasextracted.Throughthespecificamplificationofthe16SrRNAsequence,theobtainedsequencewascomparedusingBLASTontheNCBIwebsite.YD1andYD2wereidentifiedasVibrioharveyiandHalomonaslitopenaeirespectively.ThisstudyverifiedthepolysaccharidedegradationabilityofYD1andYD2strainsaccordingtothedeterminationofpolysaccharideactivitybyDNSmethod.Thisexperimentstudiesthegrowthofpolysaccharidedegradationbacteria.TheresultsshowthatundertheconditionofshakeroscillationcultureofDmedium,30℃and100r/min,6-24hoursafterinoculationistherapidgrowthperiodofVibrioHavirioandshrimpsaltmononas.Inordertoimprovetheamountofpolysaccharideenzymesproducedbypolysaccharide-degradingbacteria,thefermentationconditionsofpolysaccharide-producingpolysaccharide-producingbacteria(carrageenanconcentration,agarpowderconcentration,temperature,salinityandPH)wereoptimizedinthisexperiment.Theresultsshowthat0.25%and0.20‰carrageenaneseareselectedasthebestfermentationconcentrationofpolysaccharaseproducedbyYD1andYD2strainsrespectively;0.20%and0.25%agarpowderareselectedasthebestfermentationconcentrationfortheproductionofpolysaccharasebyYD1andYD2strains;35℃isselectedasYD.Thebestfermentationtemperaturefortheproductionofpolysaccharasein1andYD2strains;30‰salinityisselectedasthebestfermentationsalinityfortheproductionofpolysaccharinesinYD1strains,and20‰,0‰and30‰salinityasthebestfermentationsalinityfortheproductionofpolysaccharideenzymesinYD2strains;PHvaluesof7and8areselectedasYD1bacteria.TheoptimalfermentationPHvalueofpolysaccharideenzymesproducedbystrainsandYD2strains.Tosumup,YD1andYD2strainsinthebrcolonyandzhcolonyhaveagooddegradationeffectonpolysaccharidesandcanbewidelydevelopedandappliedtothemarket.Keywords：Redalgaepolysaccharide;polysaccharidedegradationbacteria;YD1andYD2strains;16srRNAsequence

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