Detection of microorganisms in different growth states based on microcalorimetry

A challenging method for sterility test which was rapid and reliable had been established to assess the adaptability and robustness of the microbial under different conditions. There were material and energy metabolism or exchange with microbial on microcalorimetry, as a result this method can be served as one of the optimization of thermodynamics sterility test. Thermal power-time curves under various environmental conditions (including processing temperature, storage time, and drugs inhibition) were determined. Typical microbial growth thermal power-time curves were obtained. The curves were analyzed qualitatively and quantitatively by similarity values of bio-profiles and thermodynamics parameters, such as the exponential growth rate constant (k), detection time (T _d). The similarity showed that microbial growth curves of low processing temperature, short storage time (1?month), and Traditional Chinese Medicine injection (Shuanghuanglian, contained native compounds) inhibiting were match better with the normal than other circumstance. Thermodynamic parameters indicated that the microcalorimetric method could detect the positive bacteria within 18?h (less than 10?cfu), and more quickly identify the different states of the bacterium growth and metabolism than routine sterility. In conclusion, characterized by of the specific and strong two-dimensional information, microcalorimetry could supply thermograms as biological profiles to describe the microbial activity under different conditions, which were not only used as a rapid and reliable identification of microbial, but also as a method for sterility test of microcalorimetry optimization.