Batch culture The best way of producing great numbers of microbes or their natural products is to culture in the liquid medium. Normally the technique we use is called batch culture(分批培养)in which the bacteria are inoculated into flasks(三角瓶)ofa suitable medium and grown at an appropriate temperature and degree of aeration(通气条件)
The best way of producing great numbers of microbes or their natural products is to culture in the liquid medium. Normally, the technique we use is called batch culture（分批培养）in which the bacteria are inoculated into flasks(三角瓶)of a suitable medium and grown at an appropriate temperature and degree of aeration（通气条件）. Batch culture
Growth curve Bacteria grown in this way show a particular pattern of growth which is referred to as the bacterial growth curve. The number of viable bacterial cells is measured over time(整个时间) and is plotted as a graph of the log10 viable cell numbers(活细胞数) against time, which is called a semi- logarithmic plot(半对数关系 Hh s). The bacterial growth curve reveals four phases of growth
Bacteria grown in this way show a particular pattern of growth which is referred to as the bacterial growth curve. The number of viable bacterial cells is measured over time（整个时间） and is plotted as a graph of the log10 viable cell numbers（活细胞数） against time, which is called a semi-logarithmic plot（半对数关系 曲线）. The bacterial growth curve reveals four phases of growth. Growth curve
Why use a logarithmic scale rather than arithmetic scale? A logarithmic scale(对数尺度) Is used to plot bacterial growth owing to the large numbers of cells produced and to reveal the exponential nature of bacterial growth. If an arithmetic scale(算术尺度) is used to plot the increase in the number of cells, a curve of increasing gradient would be een which is converted into a straight line when a logarithmic scale is used.(增加的剃度曲线变成直线) The doubling time for the bacteria can be read directly from the graph
A logarithmic scale（对数尺度） is used to plot bacterial growth owing to the large numbers of cells produced and to reveal the exponential nature of bacterial growth. If an arithmetic scale（算术尺度） is used to plot the increase in the number of cells, a curve of increasing gradient would be seen which is converted into a straight line when a logarithmic scale is used.（增加的剃度曲线变成直线） The doubling time for the bacteria can be read directly from the graph. Why use a logarithmic scale rather than arithmetic scale？
1. Lag phase(延迟期) When bacteriacare ofirstinoculadted tora medium the a periodiewhieleno growth occurs During this phasea tiegbaetera readapting to thenew environments ithesizing ew enzymes as required and increasing cell size ready for cehkdiyision Hhe ength of this time depend 0i能 ratureofthernocilo种ip comes from a fresh the same edfu the lago o phase will be stort, but if the locum is old orthen medium has been changed (especially eying bacteria from a richnedium to a poor one the lag phase wilb 0ge签
• When bacteria are first inoculated into a medium there is a period in which no growth occurs. During this phase the bacteria are adapting to the new environment, synthesizing new enzymes as required and increasing cell size ready for cell division. The length of this time depends on the nature of the inoculum(接种物，pl. inocula). If this comes from a fresh culture in the same medium, the lag phase will be short, but if the inoculum is old or the medium has been changed (especially moving bacteria from a rich medium to a poor one) the lag phase will be longer. 1. Lag phase（延迟期）
Factors that affect the time of lag phase (1) The nature of the inoculum, fresh or old.(接种龄) (2) Seed volume or pitching rate:(接种量 3) The ingredients of the medium(培养基成分)
Factors that affect the time of lag phase: (1)The nature of the inoculum, fresh or old.(接种龄) (2)Seed volume or pitching rate.(接种量) (3)The ingredients of the medium.(培养基成分)