Pilot Scale Experiment Of Producing Xylanase From Aspergillus Niger

After formerly several years work accumulation, my laboratoryafterscreening, mutation, already obtained several Aspergilus niger strains,theyhighproduces the xylanase, such as 149, J506 andA25 and so on, the activity of enzymeexactly might reach 544IU/ml. Respectively produces the xylanase the laboratorypreservation the Aspergilus niger strain to carry on further screening, and carries on thesingle fungus separation to it, obtains is strain A.niger 25 (9), the activity of enzyme ishighest .In the rockerferments the activity of enzyme exactly to achieve 589 IU/ml, so weuse it in the production experiment,and carries on 5 tons potsfermentation test. Thefermentation is finished after 88 hours,and the terminal activity of enzyme exactlyachieves above 800IU/ml.We carried the enzyme medium on furtheroptimizes,and discovered that if we don'tput 0.6% CaCO₃ in ,then we can control the culture medium initial pH value in about6.2,but is not original 7.89,relieves the step to adjusts the pH value withhydroricacid,and the final fermentated activity of enzyme also slightly has theenhancement,has achieved the ideal adjust result.Carries on the fermentation test in 20 tons fermentation pots,discovered 1 ton seed potcan meets the fermentation need, and finally the xylanase activity of enzyme achievesabove 900IU/ml, fermentation cycle between 80 - 88h.According to the laboratory result and 5 tons pots experiment result, we discovered theeffect of add 3% aid-filter material was the best choice.Carries on ultra filter to 20 tons pots fermentation fluid,discovered that under 20°Cultra filter the activity of enzyme loss is small, fermentation fluid receiving rate.achieves to 75.3%.We concentrated the enzyme fluid to join the right amount of different antiseptic: thesodium benzoate 0.2%, the sorbic acid potassium 0.2%,the sodium benzoate 0.2% +sorbic acid potassium 0.1%, the sodiumazide 0.05%, then carries standardizedprocessing on the end product enzyme take 2500IU/mL as the standard. Obtains in theproduct also have activities of the certainβ-glucosan enzyme and the celluloseenzyme. After anticorrosion and standardized ,we put each kind end product enzyme in three barrels(25kg).After 3 months in the normal temprature,we discovered the end product enzyme activities have survived rate to be higher than 90%.The antiseptic which composed by the sodium benzoate and the sorbic acid potassium,with which the enzyme activity surviving rate achieve 94.6%,will suit the industrialization production.