L-malic acid high-yielding bacterial strain and its application
A malic acid and strain technology, applied in the field of bioengineering, can solve problems such as low-price competition
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
preparation example Construction
[0026] The preparation method of the fermentation medium is as follows:
[0027] Mix corn flour and water at a mass volume ratio of 1:4 (g / mL), heat to 70°C to obtain dry starchy raw materials;
[0028] Add high-temperature-resistant a-amylase according to the addition amount of 800U / g dry starchy raw materials, heat up to 90°C and keep warm until the liquefaction is complete to obtain corn flour liquefaction liquid, filter the liquefaction liquid with filter cloth while it is hot to obtain liquefaction clear liquid;
[0029] The liquefied liquid and the liquefied clear liquid are mixed, adjusted to a total sugar concentration of 9-10% with water, 0.1-0.2 g / L urea is added, and an appropriate amount of calcium carbonate is added to adjust the pH to 6-7.
[0030] HPLC determination method of L-malic acid: Quantitative detection of fermentation components by HPLC method, using DIONEXHPLC P680 workstation, Alltech organic acid column No.88645 column 250 mm×4.6 mm, ultraviolet det...
Embodiment 1
[0031] Embodiment 1: ARTP mutagenesis treatment Aspergillus niger
[0032] Take a control slant (the slant medium is the PDA solid medium) that has been cultured for 5 to 6 days with many spores and is black, wash the cultured fresh slant spores with 5 mL of sterile water, and filter them through sterile gauze. Finally, place in a 250 mL Erlenmeyer flask filled with glass beads and Chapkin's liquid medium (it is advisable for the glass beads to roughly cover the bottom of the bottle), shake fully at 30°C and 200 rpm for 30 min to disperse the spores evenly, and obtain a single For the spore suspension, take 0.5mL and dilute it appropriately with sterile normal saline to measure the concentration of the bacterium suspension by hemocytometer method, and adjust the concentration of the spore liquid to 10 7pc / mL, as the mutagenesis stock solution. Aspergillus niger was mutagenized using the normal temperature and pressure (ARTP) plasma mutagenesis apparatus. The working gas duri...
Embodiment 2
[0033] Embodiment 2: strain screening
[0034] Preliminary screening: take 100 μL of the spore suspension obtained after ARTP mutagenesis for 180 s, spread it on the acid production indicator plate, and incubate at 30-35°C for 48-120 hours, and observe whether a color change circle can be produced to preliminarily judge whether the strain produces acid . Since nystatin was added to the acid production indicator plate, the growth rate of mold was inhibited to a certain extent, and single colonies were easily obtained. Join CaCO 3 It can make the solid medium turbid, and after producing acid, it can form calcium salt, which improves the transparency of the medium around the colony and makes the edge of the bromocresol green discoloration circle clear. By coating the mutagenized strain on the plate, select a single colony with a large ratio of the color-changing transparent circle to the colony diameter, and initially judge that it is a strain with high acid production, and tra...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More