Study On Lipid Production For Cultivating Of Lipomyces Starkeyi By Using Food Industrial Waste Water

In this study, several fermentation medium were selected and filtered by the food industrial wastewater, focusing on the production of beer wastewater to use the medium of Lipomyces Starkeyi yeast culture for fat oil production and optimization of medium and culture conditions, and small-scale fermenter with amplification experiments were intended to be used to achieve a complete beer production process conditions in treatment of oil wastewater by Lipomyces Starkeyi yeast culture, in order to provide a new way to the beer production waste water for the comprehensive utilization and processing.(1)Through the Comparison of five food industrial wastewater for oil production by Lipomyces starkeyi1809, then determine the basis fermentation medium of this experiment was used by beer production wastewater, with the condition of 10 inoculation, 28℃, 120r/min, cultivated Lipomyces Starkeyi 1809 120h, then the biomass, the lipid production, the lipid content and the proportion of degradation of waste water's COD were up to 5.16g/L,2.02g/L,39.15%å'Œ69.55%, at the same time, the methods of 24h natural subsidence , centrifugation and flocculation & centrifugation were used to different beer wastewater pretreatment, and cultured Lipomyces Starkeyi yeast under the same conditions, after test and comparision of the cell biomass, oil yield and oil content, finally the settlement of 24h natural wastewater treatment was selected.(2)The optimum medium of fermentation substrate to cultivate Lipomyces starkeyi 1809 for lipid production and the COD degradation was studied by single-factor and orthogonal design experiments,the best medium consisting of adding C/N 55:1 (Xylose 28.88g/L,(NH₄)₂SO₄ 1.00g/L), FeCl₃·6H₂O 3.0mg/L to the beer wasterwater; initial pH was 5.5;adding Tryptophl 150μmol/L after 36h fermentation.The optimal fermentation conditions were as follows:100mL of medium in 500mL Erlenmeyer flask, inoculation amount 10%, 28℃, 120r/min.Under these conditions,the biomass was up to 12.28g/L, the lipid production was up to 4.40g/L, the lipid content was 35.80%,the proportion of degradation of waste water's COD was up to 50.32%. They biomass and lipid production increased by 137.98% and by 117.82% respectively. optimization result is obviouse. (3)The optimum condition of fermentation was determined by single-factor and orthogonal design experiments: inoculation volume 3%,volume 130ml/500ml,temperature 26℃,shaking speed 160 r/min,culture time 144h. Under these conditions,the biomass was up to 13.83g/L, the lipid production was up to 5.25 g/L, the lipid content was 37.92%,the proportion of degradation of waste water's COD was up to 79.08%, the IUFA was up to 65.46%, the bioma,the lipid production, the proportion of degradation of waste water's COD and the IUFA increased by 168.02%,159.90%,13.70%å'Œ1.36% respectively,the optimization effect is significant. When it reched 120h of the fermentor training,the biomass, the lipid production, the lipid content and the proportion of degradation of waste water's COD are all reache the maximum,they are 13.34g/L,4.82g/L,36.13% and 85.09% respectively, and it is similar with the result of the orthogonal design experiments under the best congditions, but the COD's degradation was promoted by 7.59% and the period of fermentation was shortened 1 day. The analysis of the fermentation kinetics showed that the substrat's consumption and the COD's degradation belong to the type which is related with the growth,and the lipid's generation belong to the type which is related with the growth partially.