The Study On Liquid Submerged Culture And Industrial Application Of Actinomucor Elegans

Ar.tinomucor elegans is an excellent stain used in the fermention of sufu. The quality of Mucor stain has an extraordinary effect on the production of sufu. The research on it, however, home and abroad, has seldom been reported. What is more, there is no account of the research on the property of its growth and protease activity on the condition of liquid submerged fermentation, on the liquid mucor spawn used in sufu production.In order to improve the traditional stain production process of sufu and apply the up-to-date fermentation technique to the manufacturing process of sufu, we made the research on liquid submerged culture of Actinomucor AS3.2778 and on the industrial application of the liquid mucor spawn. By this way, we hope to improve greatly the productive process automation and its scale, and the quality of sufu production. In addition, we studied the growing characteristics, the fermerntation conditions and the protease activity of Actinomucor AS3.2778.The results of the experiments showed that Ar.tinomucor elegans AS3.2778 can grow well in the soybean powder liquid medium at 28 on a rotary shaker with a speed of 200rpm.Within 24 hours, the mycelium greatly massed and in the end, the average biomass(dry weight of mycelium) reached 1.02g/l00ml.Its growth accorded with the Growth Model of Rogistic.The second stage fermentation had nearly no Lag period and came directly into Exponential period, and Steady period after 36-40 hours.There were certain glucoamylase activity and lipase activity,and higher protease activity in the culture fluid.Single factor experiments and the variance analyses showed that soybean powder, sucrose, KH2PO4 all can improve the protease activity in the liquid. The result indicated that in a certain range, the more concentrated the maltose, the less advantageous to outcome of the protease .The adequate C:N ratio in medium is about 1.2.The lower C:N ratio is advantageous to the production of mucor protease. Better ventilative is needed for the production of the proteinase of Actinomucor elegans AS3.2778.The initial optimal pH is 6,and the protease outcome was at its height at 36 hours.The industrial fermentation and production application process showed that the biomass of Actinomucor elegans AS3.2778 was able to reach respectively 24.55g/100ml and 27.69g/100ml (wet weight of mycelia:)at 24h in the 50L generalfermentor and 180L external airlift fermentor, with soymilk and soy whey as medium,on the condition of 28 ,air condition 1:1 vvm(0-12h),l:2vvm(12h -). Airlift fermentor showed many adventages. The liquid spawn of Actinomucor elegans AS3.2778 did well in sufu production, its fermentation period being 16-24 hours. When being diluted by 2 times, the culture fluid showed obvious adventages over the productive strain, shortening the primary fermentation period by 6-8 hours and forming thicker mycelial mat.The research proved that it is totally feasible for the liquid spawn of Actinomucor elegans AS3.2778 by the industrial submerged culture to be used in the production proscess of sufu. At present, the study has been already used successfully in the actual industrial production of sufu and displayed very good applicabitity.