Production Of Caroteniod Functional Feedstuff By Fermentation Of Vinegar Residue

In this paper,in order to improve the nutritional value and the effectiveness of vinegar residue,the production of carotenoids by the fermentation of Rhodotorula and Neurospora Sitophila was studied.First of all,vinegar residue was hydrolyzed by acidic hydrolysis and enzymatic hydrolysis respectively.Single factor tests and orthogonal experiment design methodsL9?3?4 were applied to analyze the influence of hydrolysis condition on the yield of reducing sugar of the vinegar residue.Under optimal conditions 33.89%.of reducing sugar was obtained by enzymatic hydrolysis and 39.46%was obtained by acidic hydrolysis.Then the content of CF?Crude Fiber??ADF?Acid Detergent Fiber??DNF?Neutral Detergent Fiber?were determined by Van Soest method.Rhodotorula was cultured on the hydrolyzed vinegar residue with the Rhodotorula directly cultured on vinegar residue as the control.After the enzymatic hydrolysis and the fermentation of Rhodotorula,the content of carotenoid in the vinegar residue was 19.94mg/g.After the acidic hydrolysis and the fermentation of Rhodotorula,the content of carotenoid in the vinegar residue was 17.61mg/g By the analysis and data processing,it has been found that the enzymatic hydrolysis was better than that of acidic hydrolysis and the direct culture of Rhodotorula in vinegar residue.By using the enzymatic hydrolyized vinegar residue,the culture condition of the production of carotenoids by rhodotorula solid fermentation was optimized by single factor method.The effect of nitrogen source,the addition amount of water,the value of pH,the addition amount of MgSO₄,the solid volume in flask and the inoculation volume on the yield of carotenoids were studied.Under the fermentation condition of 28 ? and 120h,the maximum biomass of 13.5mg/g the maximum carotenoid yield of 120.36ug/g and the maximum carotenoidscontent of 107.32?g/g were obtained at the optimum condition.Secondly,the condition of the fermentation vinegar residue by Neurospora Sitophila was optimized.The optimal proportion of vinegar residue,tofu dregs and bran in the mixed fermentation was 10:1.5:1.And the proportion of added MgSO₄ and K₂HPO₄ is 0.15:0.0365.Under this culture,the accumulation of enzymes were studied.when the culture time was 72h,the activity of phytase and xylanase reached the maximum of 53U/ml and 1599U/ml respectively.The cellulase activity reached the maximum of 94.37 U/ml at 60 h.And the content of carotenoids reached a maximum of 8466.69 ug/g at 84 h.Finally,thermal-acid method was used as cell-wall broken method.Acetone was used for carotenoids extraction.The total carotenoids content was determined by adopt thin layer chromatography and spectrophotometric method.The results showed that the rhodotorula pigment contained at least four components,and the Neurospora Sitophila pigment contained six components.the two components of the pigment produced by the two strains were the same.At the same time,the fermentation of vinegar residue was conducted by using Neurospora,Rhodotorula and mixed strains of Neurospora and Rhodotorula respectively.the results were shown as following.The highest degradation rate of cellulose was obtained by the fermentation of Neurospora,The acid detergent fiber decreased by 19.81%and the neutral detergent fiber decreased by about 17.58%,The highest crude protein content was obtained from the mixed fermentation,which increased by 4.2%.In the determination of crude fat,the content of Rhodotorula was the highest,but increace by 1.3%.The highest content of reducing sugar was the medium of Neurospora,The content of reducing sugar was 36.11%.The highest content of carotenoid was obtained from the Neurospora fermentation,and the carotenoid yield was 687.11ug/g.