胶红酵母的酶解工艺优化及其发酵产物在蛋鸡生产中的应用OA

This experiment was conducted to study the optimization of enzymatic hydrolysis process for Rhodotorula mucilaginosa and its fermentation product application in production of laying hens.The in vitro en-zymatic hydrolysis experiment used a single-factor experiment,to study the effects of compound enzyme(acid-ic mannanase and β-glucanase)addition amount and addition ratio,enzymatic hydrolysis time,enzymatic hy-drolysis temperature and enzymatic hydrolysis pH on carotenoid extraction rate of Rhodotorula mucilaginosa mutant strain CS-15.Further optimization of process conditions for carotenoids from Rhodotorula mucilaginosa by enzymatic method using Box-Behnken response surface methodology.A total of 180 Hy-Line brown laying hens aged at 22 weeks with similar body condition were randomly assigned to 3 groups with 6 replicates per group and 10 hens per replicate.The laying hens in group A(control group)were fed a basal diet,and others in group B and group C were fed basal diets supplemented with 1%and 2%Rhodotorula mucilaginosa fermen-tation product,respectively.The pre-experimental period lasted for 3 days,and the experimental period lasted for 28 days.The results showed as follows:1)the optimal addition ratio of compound enzyme was acidic mannanase∶β-glucanase=1∶2,and the optimal addition amount was 100 mg/L.Under the addition ratio and addition amount,the carotenoid extraction rate reached 63.14%.The optimal process conditions were hydroly-sis time of 5 h,hydrolysis pH of 4.5 and hydrolysis temperature of 50℃.Under these conditions,the predic-ted carotenoid extraction rate was 75.51%,and the actual extraction rate was(74.50±0.18)%.2)The yolk Roche color level and carotenoid content at various time points of group B and group C were significantly high-er than those of the control group(P＜0.05),and group C was significantly higher than group B(P＜0.05).There were no significant differences in egg production rate,eggshell strength and eggshell thickness et al a-mong all groups(P＞0.05).In conclusion,the experiment optimizes the conditions for extracting carotenoids from Rhodotorula mucilaginosa by enzymatic hydrolysis using compound enzyme,and through animal experi-ments,it has been confirmed that the Rhodotorula mucilaginosa fermentation product can safely replace syn-thetic additives,effectively improve the yolk color and nutritional value of eggs.[Chinese Journal of Animal Nutrition,2026,38(4):2651-2662]