瘤胃微生物体外降解不同来源肽的速度研究

在体外分别研究了 36 ,72 ,14 4 ,2 16 ,32 4 ,4 5 0mg·L-16个水平的大豆肽、玉米肽和瘤胃液肽在瘤胃微生物培养液中的降解速度。结果表明 :随着培养时间的延长 ,3种来源肽处理的培养液中肽的含量均极显著降低 (P <0 0 1) ;对不同的肽源来说 ,瘤胃液肽降解得最快 ,培养后单位时间肽浓度最低 ,大豆肽降解速度次之 ,玉米肽降解得最慢 ,培养后单位时间肽浓度最高 (P <0 0 5或P <0 0 1) ;培养后单位时间内由玉米肽降解产生的游离氨基酸氮 (FAAN)数量最少 ,大豆肽次之 ,由瘤胃液肽降解产生的FAAN数量最多。结果表明 :肽的来源不同 ,其降解速度有异 ,瘤胃液肽和大豆肽降解速度较快 ,玉米肽较慢 ;培养液中FAAN含量过高可能限制了肽的降解。

Studies on the degradation rate of different peptides in the culture by rumen microorganisms

Peptides from soy,corn and rumen fluid were incubated with rumen fluid curture and the degradation of the peptides by rumen microorganisms was investigated The results showed that degradation amount of different peptides were decreased significantly( P <0 01) with incubation time extending The rumen fluid peptides were degraded fastest and soybean peptides were degraded faster and corn peptides were degraded slowly( P <0 05 or P <0 01);The amount of FAAN released from corn peptides was less than those of FAAN from rumen fluid peptides in the culture The results suggested that the degradation rate of peptides varied depending on the protein source and the composition of the peptides