The drug development scheme used by the National Cancer Institute begins with a drug discovery program (prescreen and screening phase). Since ascites (腹水) tumors are useful in identifing potentially active agents,a prescreening step using the P388mouse le...[繼續(xù)閱讀]

    In the production of L-glutamic acid,two enzymes have been shown to play important roles:phosphoenolpyruvate carboxylase (PC,磷酸烯醇丙酮酸羧化酶),which catalyzes carboxylation of phosphoenolpyruvate to form oxaloacetate,(草酰乙酸) and α-ketoglutarate dehydrogenase (KD...[繼續(xù)閱讀]

    White wine is the product of the fermentation of pure grape juice obtained from grapes by extraction from grapes. Macereation of the skins should be avoided and the must should be clarified by settling,One distinguishes two basic types,the dry,white wines...[繼續(xù)閱讀]

    Introduction There has been a world wide interest recently in the application of commercially available lipases for the hydrolysis of oils,(1,2)synthesis of esters,(3,4) interesterification of oils and fats,(5) production of biosurfactants,(6) and the res...[繼續(xù)閱讀]

    There are two basic types of Scotch whiskey,namely,malt whiskey and grain whiskey.Malt whiskey is made from peated barley malt as the only source of starch for the production of malt whiskey,the enzymes in the malt change the starch to sugar during the ma...[繼續(xù)閱讀]

    Between the traditional biotechnologies and the newer inovations lies a history of developments with a number of important milestones on the way.In any study of these developments it is clear that strategic and economic necessities as well as the inventiv...[繼續(xù)閱讀]

    In various traditional oriental foods (for example koji,miso) the nutrientional value of foodstuff is improved by microbial,usually fungal growth. Wheat or rice bran is a common starting material,and is rendered more digestible,more nutritious and more fl...[繼續(xù)閱讀]

    Suppose the aim of a process is to manufacture 1000 tonnes of phenylalanine per year.Phenylalanine concentrations of 20g/L can be expected and the yield of phenylalanine from glucose is 0.13 g phenylalanine per g glucose consumed.Tyrosine (酪氨酸) is require...[繼續(xù)閱讀]

    Horticultural (與園藝有有的,園藝學(xué)的) practice has long made use of vegetative cloning of plant parts (shoots,leaves,etc. ) for selective and rapid propagation of many plant species. Subsequently,plant tissues such as root tips,cambium (形成層) or plant tumours were f...[繼續(xù)閱讀]

    All matter is composed of basic substances called elements. An element cannot be broken down into esimpler units by chemical reactions;it contains only one kind of atom.An atom is the smallest characteristic unit of an element.A compound is a substance th...[繼續(xù)閱讀]