4微生物培养基Culturalmedium.pptx

4.微生物培养基Culturalmedia4.1培养基的类型及功能ClassificationsofmediaandtheirfunctionsThechoiceofdefinedorundefinedmediumisdependentuponitsapplication.---Chemicallydefinedmediaareusefulinbiochemicalormetabolicstudiesoforganisms.--Generallaboratorygrowthmediaandindustrialmediaareoftenchemicallycomplex.Suchas花生饼、蛋白胨等。一般不需外加微量元素(traceelements)、维生素等。按状态分类：-Solidmedia：suitabletocultureandpreservespeciesandspores;cultivatingfungi.-Liquidmedia:80%-90%waterindustrialfermentationmedia.-Semi-solidmedia:liquidmedium+agar主要用于鉴定细菌、观察细菌运动特征等。按用途分类孢子培养基、种子培养基和发酵培养基1.孢子培养基sporemedia要求：使菌体迅速生长产生较多的优质孢子不易引起菌种发生变异(variation)。基本配制要求：⑴notrichinnutritionespeciallyorganicnitrogensoure.⑵optimalmineralsaltconcentration⑶optimalpHandhumidity生产上常用孢子培养基：麸皮、大米、小米培养基；由葡萄糖、蛋白胨、牛肉膏和食盐等配制的琼脂斜面培养基。大米和小米常用作霉菌孢子培养基因它们含氮少、疏松、表面积大是较好的孢子培养基。水分控制在21％－25％。种子培养基inoculummedia:种子培养基是供孢子发芽、生长和大量繁殖菌丝体并使菌丝体长得粗壮成为活力强的‘种子’。Inoculummediaareusuallylessnutritiousthanareproductionmediaandtheyusuallycontainaconsiderablylowerlevelofthemainnutritivecarbonsource.一般种子培养基常包括有机氮源和无机氮源最后一级的种子培养基的成分最好接近发酵培养基。发酵培养基productionmedia发酵培养基是供菌体生长、繁殖和合成产物之用。要求：既要使种子接种后能迅速生长达到一定的菌丝浓度又要使长好的菌体迅速合成所需产物。配制要求：其组成除有菌体生长所必需的元素和化合物外还需有合成产物所需的特定元素、前体和促进剂等。Inadditiontothecarbonandnitrogencompoundsamediumcontainsinorganicsaltsvitaminsgrowthfactorsprecursorsoffermentationproducts.Microbialgrowthunderindustrialfermentationconditionsusuallyutilizesa“luxurymetabolism”oftheorganisms.Thusgoodyieldsoffermentationproductsoccuronlyifrelativelylargeamountsofcarbonandpossiblynitrogenarechanneledthroughthemetabolicpathwaysofthemicroorganism.4.2发酵培养基的成分及来源Compositionofmediaandtheirsources4.2.1碳源carbonsources4.2.1.1糖类sugarsmolasses(糖蜜)Beet(甜菜)andcanemolassesareby-productsofthesugarindustry.containing50%-75%fermentablesug