Method for preparing L-lactic acid through lactobacillus paracasei fermentation
A technology of Lactobacillus and by-cheese, applied in the field of fermentation engineering, can solve the problems of high cost, low yield, complex L-lactic acid production process, etc., and achieve the effects of simple operation, sufficient nutrients, and reduced product inhibition
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Examples
preparation example Construction
[0027] 2. Preparation of seed solution
[0028] Take the slant culture, wash the lawn with 1-5ml of physiological saline, inoculate it into the seed medium according to the volume fraction of 0.1%-0.3% inoculum, place it at a temperature of 35°C-45°C, and cultivate it at a speed of 160-200rpm / min.
[0029] The components of the seed medium are: glucose 20-40g / L, soybean peptone 15-25g / L, yeast extract powder 3.0-7.0g / L, dipotassium hydrogen phosphate 1.0-3.0g / L, magnesium chloride 0.5-1.0g / L L, manganese sulfate 0.1-0.5g / L, sodium chloride 1.0-3.0g / L, calcium carbonate 0.5-1.5g / L, Tween-80 0.5-1.5g / L, initial pH value 6.8-7.0;
[0030] 3. Fermentation and fermentation process control
[0031] Cultivate the primary seed liquid for 3-8 hours, stop the cultivation when the pH reaches 4.0-5.0, transfer to 35L fermentation medium according to the inoculum size of 3%-7%, the initial pH is 6.8-7.0, the temperature is 35°C-45°C, The speed is 80-100rpm / min. When the residual sugar re...
Embodiment 1
[0034] In this example, five organic nitrogen sources, namely yeast extract, corn steep liquor, peptone, yeast extract powder, and beef extract, were selected as the single organic nitrogen source. The other components of the fermentation medium were kept the same, and the fermentation process was controlled unchanged. L, the production of L-lactic acid was measured after the fermentation, and the content of L-lactic acid produced by fermentation with different organic nitrogen sources is shown in Table 1 below.
[0035] Table 1
[0036] organic nitrogen source
[0037] It can be seen from Table 1 that when using corn steep liquor and yeast extract as a single nitrogen source, compared with other high-cost nitrogen sources, the L-lactic acid production can reach 181g / L and above, and the glucose conversion rate is higher than 90.5%. The composition of pulp and yeast extract is complex and rich in various nutrients, such as biotin, B vitamins, pyrimidine, purine, etc....
Embodiment 2
[0039] This embodiment provides a kind of method utilizing Lactobacillus paracasei fermentation to prepare L-lactic acid, comprising the following steps:
[0040] 1. Activation of bacteria
[0041]Take the Lactobacillus paracasei glycerol tube bacteria liquid stored at -70°C, inoculate it on the MRS solid medium plate by streaking, and culture it statically in a constant temperature incubator at 35°C for 24 hours.
[0042] On the MRS solid medium, use an inoculation loop to pick a single colony of Lactobacillus paracasei, streak it on the MRS solid slant, and culture it statically in a constant temperature incubator at 40°C for 18 hours.
[0043] 2. Preparation of seed solution
[0044] Take the slant culture, wash the bacterial lawn with 5ml of physiological saline, inoculate it into the seed medium at a volume fraction of 0.2%, place it at a temperature of 40°C, and cultivate it at a rotational speed of 180rpm / min.
[0045] The composition of the seed medium (by mass parts...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More