Research On Production Of Feed Yeast And Yeast Extract With Penicillin Mycelium

With the development of pharmaceutical enterprises in China, the number ofantibiotics mycelium is so enormous that can not be ignored. Now, the treatment ofthe penicillin mycelium has became a big problem for the pharmaceuticalenterprises. Because of the high organic matter content, especially high proteincontent in penicillin mycelium, there are some related researches were reported atdomestic and foreign currently to study the treatment and disposal of penicillinmycelium. The detoxification of the mycelium is the key problem to make use ofthe penicillin mycelium.This article analyses the component of the penicillin mycelium. To utilize theHigh protein and eliminate penicillin, dilute acid and penicillin mycelium wereheated together to get the pretreatment solution, and then put the separated yeastinto pretreatment solution for cultivation of yeast cells,which can be made into feedyeast. Finally, the yeast cells are broken for extraction of yeast extract. This articleindependently provides two sets of technology to utilize penicillin myceliumincluding production of feed yeast and yeast extract, which have great referencevalue for manufacture practice and production.Firstly, dilute acid and penicillin mycelium were heated together and thetechnological parameter of pretreatment were optimized to eliminate penicillin andutilize the high protein. The optimal pretreatment condition: original pH is5.25,time is6hours, liquid to solid ratio is2and the temperature is85℃.Secondly, the yeast strain which was separated in dilute acid and antibioticenvironment was identified by other partner.the morphological characteristics of theyeast strain was observed and its growth factor was optimized. The optimal growthfactor of this yeast were given as follow: the temperature is31~34℃, the originalpH is5.5, the rotate speed is150rpm and the inoculum size is1%. From the growthcurve of the yeast, we can see that it can be seed solution with the culture time of12hours. The result of yeast domestication with the pretreatment solution is preferable.The yeast with domestication grows better in the high concentration of pretreatmentsolution.Thirdly, the production of feed yeast with pretreatment solution was studied.the yeast was inoculated into the pretreatment solution in the optimal condition withthe glucose concentration of20g/L and no nitrogen source. The optimal conditionwas given as follow: the original pH is5.5, the temperature is31℃, the inoculumsize is1%, the rotate speed is150rpm. When the yeast was cultured in48hours,97%of the glucose and91.5%of the polysaccharide was used and the protein approximately reduced by64.1%. The yeast reached the stable period at48hourswhen it can be made into feed yeast. The yield of feed yeast is19.64gram with thepenicillin mycelium of100gram in dry weight. The feed yeast meet nationalstandards without penicillin residues.Finally, through the research of yeast extract, we can find that the effect isparticularly better with the addition of papain. Compared with the yeast extractwhich has no additional enzyme, we can find that the autolyzed time shorten16hours and the content of amino acid nitrogen increase118%, net yield increase by14.56%. The yield of yeast extract is57.5gram with the penicillin mycelium of100gram in dry weight. The yeast extract meet national standards without penicillinresidues.