Method for rapidly determining number of bacterial in lactic acid bacillus subtilis production liquid culture

Abstract

The invention belongs to the field of biology, and especially relates to a bacteria counting method, particularly to a method for rapidly determining the number of bacteria in a lactic acid bacillus subtilis production liquid culture. The method comprises the following concrete steps: taking a sample and washing, diluting the washed sample by using a diluent until an OD600 value is not greater than 0.8, and recording a dilution multiple, wherein the total number of the bacteria meets the following formula that: the total number of the bacteria=OD600 value*dilution multiple*2.2*10<9>CFU / mL. According to the present invention, automatic detection and counting by using instrument are achieved; the traditional bacterial culture counting adopts manual operation, such that reliability is substantially affected by experience of a testing person, and the automatic instrument detection shows advance of the detection method; the method of the present invention is simple and rapid; and a corresponding relationship among the light wave wavelength adopted for detection, the determined OD value, and the number of the produced lactic acid bacillus subtilis is determined, and the result is accurate.

Description

technical field [0001] The invention belongs to the field of biology, and in particular relates to a technical method of bacteria. Background technique [0002] With the rapid development of the national economy and the improvement of people's living standards, people have put forward higher and newer requirements for the breeding environment and safe and healthy animal products. In recent years, animal food safety incidents that have been exposed frequently, such as the "lean meat powder incident" and "melamine milk incident", have all dealt a heavy blow to the animal breeding industry and caused a serious crisis of trust. As the world's largest animal breeding country, China's export of animal products plays an important role in the national economy. However, in recent years, some countries such as Europe and Japan have used food safety issues as barriers to refuse the entry of some animal products from my country, which has caused undue damage to our economy. loss. These...

AI Technical Summary

Problems solved by technology

However, the optical density or transmittance is not only affected by the concentration of bacteria, but also affected by factors such as cell size, shape, culture medium composition, and the wavelength of light used, and usually only detects suspensions containing a large number of bacteria. The relative number of bacteria can not be determined by this method for samples or tissue samples that are too dark in color, but this method is simple and quick

The main key to the determination of the number of bacteria by turbidimetry is how to eliminate the interference in the sample, the determination of the wavelength of the light wave used and the corresponding relationship between the measured OD value and the number of bacteria, otherwise only the relative number of bacteria can be judged but not determined accurate count of bacteria