Starch degrading enzymes include α-amylase,glucoamylase,glucose isomerase,pullulanase.The amylase catalyzes the hydrolysis of starch,and the product of the reaction is a soluble dextrin hydrolyzate with a DE of 10-15,suitable for the following saccharific...[继续阅读]

    Enzymes are often used as nonrecoverable chemical reagents,in which case they are added to the substrate,incubated at the required temperature and pH for a period and subsequently destroyed. Amylase,proteases and other inexpensive bulk enzymes are used in...[继续阅读]

    Nucleotides are vital to the operation and the reproduction of cells. Each nucleotide contains three different kinds of components: a five-carbon sugar (ribose or deoxyribose),a nitrogen-containig base (either a single-ringed pyrimidine or a doubleringed ...[继续阅读]

    Glycerides are the most abundant lipids and the richest source of energy in the body. A glyceride molecule has one,two,or three fatty acid tails attached to an alcohol backbone. In this case,the alcohol is glycerol.The terms monoglyceride,diglyceride,and ...[继续阅读]

    1. Introduction The Pierce BCA≠Protein Assay Reagent (一种分析试剂的名称) is a highly sensitive reagent for the spectrophotometric (分光光度计的)determination of protein concentration. This unique reagent system combines the well known reaction of protein with Cu2-in an...[继续阅读]

    Of the many thousands of microbial species,relatively few are currently exploited.Some important products and producer microorganisms are given in table 1,and while this list is by no means exhaustive it emphasizes the scope of the biotechnology. The prin...[继续阅读]

    Two major classes of cells,prokaryotes and eukaryotes,exist in nature and both types are used in industrial fermentation processes. The cellular properties of the two types are different.Bacterial cells belong to prokaryotes,and fungal yeast,animal and pl...[继续阅读]

    Both in the laboratory and in industry it is necessary to have available for relatively long periods important strains (type strains or good producing agents).Previously,it was customary to maintain strains on slope agar (斜面) at low temperatures in the re...[继续阅读]

    Fluids are described as Newtonian when their flow characteristics obey Newton’s law of viscosity.When a fluid is contained between two parallel plates of area A and distance X apart and if one plate is moved in one direction at a constant velocity,the liq...[继续阅读]

    Fermentation may be carried out as batch,fed-batch or continuous processes or variations of these procedures. Batch culture may be considered as a closed system(except for aeration) containing a limited amount of medium,in which the inoculated culture pas...[继续阅读]