A kind of aspergillus niger mutant strain and application thereof
A technology of Aspergillus niger and fermented strains, which is applied in the field of microbiology and can solve the problems of few studies on bacteria and actinomycetes
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0040] Embodiment 1 starts bacterium Aspergillus niger shake flask fermentation and enzyme activity detection
[0041] The starting bacterium Aspergillus niger NSP-1 (Aspergillus niger NSP-1) (this bacterial strain was screened from the soil in Laoshan District, Qingdao City by Xu Xiaodong, one of the inventors, in January 2015) was inoculated onto a fresh PDA plate, cultivated at 30°C for 5 -7d.
[0042] Cut the bacterium block of 2cm * 2cm size, inoculate to 50ml liquid shaking flask culture medium (wheat bran 2%; Lactose 0.3%; Corn steep liquor 2%; Ammonium sulfate 0.5%; Potassium dihydrogen phosphate 0.35%; Dipotassium hydrogen phosphate 0.75%; magnesium sulfate heptahydrate 0.03%), fermented in 30°C for 5 days; the fermentation broth was centrifuged, and the obtained supernatant was the crude enzyme liquid; the supernatant was subjected to cellulase and glucanase respectively , Determination of enzyme activity of xylanase and mannanase. The results showed that the xylan...
Embodiment 2
[0101] Embodiment 2 ultraviolet mutagenesis and screening of mutant bacteria
[0102] Determining the lethality rate: Inoculate the above-mentioned Aspergillus niger NSP-1 on a PDA plate and culture at 30° C. for 5-7 days. When the surface of the colony turns black and a large number of spores are produced, draw 5ml of sterile water to elute to obtain the spore liquid, resuspend with sterile water after centrifugation, and count with a hemocytometer. Take a 90mm Petri dish, add 5ml diluted spore suspension (concentration is about 1×10 7 per mL), added to the rotor and stirred on a magnetic stirrer to make the spore liquid in a uniform state. In a sterile ultra-clean workbench, use a UV lamp with a power of 9w to irradiate above a vertical distance of 20cm for 30s, 45s, 60s, 75s, 90s, 105s, and 120s respectively, and take the irradiated spore liquid and dilute 10, 100, 1000 times, take 100ul coated PDA plate, culture at 30°C for 2-3 days and then count, take the unirradiated ...
Embodiment 3
[0109] Example 3 20L fermenter fermentation verification
[0110] The starting bacterium NSP-1 and the mutant bacterium Aspergillus niger NSP-5 were respectively inoculated in the same shake flask seed medium (glucose 10-30g / L, potato 100-200g / L), 30°C, after 200rpm shaker culture for 20h, Then fermented liquid is transferred to 20L fermentation tank respectively (recipe is: wheat bran 2%; Lactose 0.3%; Corn steep liquor 2%; Ammonium sulfate 0.5%; Potassium dihydrogen phosphate 0.35%; Dipotassium hydrogen phosphate 0.75%; Heptahydrate Magnesium sulfate 0.03%), the temperature is all controlled at 30 ± 1 ℃, the pH value is all controlled at 5.0 ± 0.2, and the stirring speed is 600rpm. After cultivating in the fermenter for 24 hours, start to add xylose+glucose inversion syrup (the formula is: 25% xylose, 25% glucose, 85% phosphoric acid 5% v / v, 121°C for 30 minutes) to induce the bacteria to produce enzymes, the dissolved oxygen is controlled at 30-40%, and the fermentation tim...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More