Optimization of Fermentation Process of Corn-Soybean Meal Diet for Piglets Using Response Surface Method and Its Protein Secondary Structure Analysis
This experiment aimed to optimize the synergistic fermentation process of piglets'corn-soybean meal diet using bacteria and enzymes with response surface method(RSM),and to study its protein secondary structure characteristics.The objective was to provide reference and guidance for the application of fermentation technology in livestock and poultry diet production.Firstly,single-factor experiment was conducted to screen influencing factors,followed by the optimization of the fermentation process using RSM to determine the opti-mal fermentation conditions.Finally,the corn-soybean meal diet was divided into 4 groups according to differ-ent treatments:basal diet group(CK group),lactic acid bacteria group(B group),enzyme group(E group)and bacteria-enzyme synergistic group(BE group).Fourier transform infrared spectroscopy(FTIR)technolo-gy was used to analyze the protein secondary structure of the corn-soybean meal diet before and after fermenta-tion.The results showed as follows:1)the optimal fermentation process for the corn-soybean meal diet was bacterial inoculation amount of 6.0％,enzyme addition of 0.036％,fermentation temperature of 33.0 ℃,fer-mentation time of 45.0 hours,feed-to-water ratio of 1:1,and sucrose addition of 2.0％.2)Under these condi-tions,the crude protein content of the B,E and BE groups increased by 12.91％,13.42％and 17.28％,and the acid-soluble protein content increased from 1.97％to 3.28％,3.39％and 3.83％,respectively,compared with before fermentation.3)Obvious differences in molecular structure of the corn-soybean meal diet were ob-served before and after fermentation.The amide Ⅰ peak area of the BE group was significantly higher than that of the other three groups(P＜0.05).The ratio of the amide Ⅰ peak area to the amide Ⅱ peak area and the ra-tio of the amide Ⅰ peak height to the amide Ⅱ peak height of the BE group were significantly higher than those of the other three groups(P＜0.05).The α-helix peak area of the BE group was significantly higher than that of the other three groups(P＜0.05),and the ratio of β-sheet peak area to a-helix peak area was signifi-cantly lower than that of the other three groups(P＜0.05).In conclusion,the bacteria-enzyme synergistic fer-mentation improves the nutritional value of the corn-soybean meal diet,making the protein more digestible and utilizable by livestock and poultry,and superior to feed fermented solely by bacteria or enzymatically hydro-lyzed by enzyme preparations.[Chinese Journal of Animal Nutrition,2024,36(11):7320-7334]
万方数据
维普
