Study On Production Of Thalli Feedstuff Bymycelial Fungus

Thalli feedstuff has many advantages such as fast growth, manifold stuff, easily producing and luxuriant nutrition. In this paper, a mycelial fungus is used as strain for producing thalli feedstuff in order to sustain yield at low temperature in winter of northern China and utilize cheap resource.Mycelial fungus Z02 separated from floccules of Leptomitus is used for producing thalli feedstuff for the first time, optimum culture medium and condition are acquired, nutritional components of mycelium are analyzed, utilization of cheap resource for producing thalli feedstuff is explored.A strain of fungi belongs to Leptomitus is separated, named Z02, which can keep growing and metabolizing at 4℃and be considered as good capability of working at low temperature. The optimum carbon source is sucrose while the optimum nitrogen source is peptone, and the fungus can keep activity in 24 hours.Optimum culture medium and condition are acquired, meliorated from Czapek dox culture medium, the optimum carbolic concentration is 30g/L with sucrose, the optimum nitric concentration is 3g/L with peptone, the initial culture pH is 5.0, the culture temperature is 35℃, the revolution of shaking table is 140 r/min, the better method and biomass for inoculation is using mycelial fragment at concentration of 10%,the time for cultivating is 24 hours. In this condition, mycelial harvest is more than 3g/L.Analysis of nutritional components shows that, the total carbohydrate content of dry mycelium is 25.83%, the crude fibre content of dry mycelium is 9.21%, which is a kind of carbohydrate not easy to be digested by animals. Because of high total carbohydrate content and low crude fibre content, the mycelium of Z02 is nutritious to animals.Utilization of cheap resource for producing thalli feedstuff is explored, molasses is used to cultivate mycelium. The results shows that molasses can be used for producing thalli feedstuff, the mycelial harvest is around 2g/L at concentration of 5.5mL/L cultivated by complete medium, while the harvest is lower cultivated by simple medium. But high molasses concentration brings high COD and chroma which are bad for next process of disposal. The feasibility of synchronously performing both thalli feedstuff cultivation and saccharide organic waste water pretreatment is discussed. In SBR reactor, mucelium has adapted the environment as time moves on, the biomass increases and the flocs forms, good liquid solid separation is convenient to reclaim thalli feedstuff. Near the end of operation, the biomass is around 2g/L. Mycelium can remove part of COD, but the removal rate is not high, the COD of outgoing water is still strong. As the system is emerged in the air, intrusion by some other microbes is existent.