不同水平蛋白质底物对猪结肠微生物体外发酵特性和菌体合成能力的影响  

Effects of Different Levels of Protein Substrates on Fermentation Characteristics and Microbial Protein Synthesis Ability of Porcine Colonic Microbiota

作　　者：葛婷[1] 孙巍巍[1] 朱伟云[1] 

机构地区：[1]江苏省消化道营养与动物健康重点实验室,南京农业大学消化道微生物研究室,南京210095

出　　处：《动物营养学报》2016年第7期1998-2004,共7页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：国家自然科学基金(31430082);国家重点基础研究发展计划(973)(2013CB127300);江苏省自然科学基金(BK20130058)

摘　　要：本试验旨在体外条件下,探究不同水平蛋白质底物对猪结肠微生物发酵特性的影响,了解猪结肠微生物对蛋白质的利用规律。以成年猪结肠内容物为微生物接种物,在结肠微生物发酵液中分别添加0(C组)、0.10(L组)、0.25 g/L(H组)酪蛋白水解物,厌氧发酵不同时间点(3、6、9、12、18、24 h),分别测定累积产气量、p H及微生物蛋白、氨态氮、挥发性脂肪酸浓度。结果显示:1)发酵3、6 h时,L组和H组p H显著低于C组(P<0.05)。2)L组和H组累积产气量均高于C组。3)L组和H组各时间点微生物蛋白浓度均显著高于C组(P<0.05),6 h时H组又显著高于L组(P<0.05)。3)L组和H组各时间点氨态氮浓度均显著高于C组(P<0.05)。4)短链脂肪酸和支链脂肪酸浓度随着发酵时间延长而增加,同时随着蛋白质水平增加而增加。由此可见,蛋白质底物的添加促进了肠道微生物菌体合成,但是过多的蛋白质底物水平并不能进一步提高微生物蛋白浓度;随着蛋白质水平增加,肠道微生物发酵特性进一步提高。This study was conducted to evaluate the characteristics of porcine colonic microbial fermentation under different protein substrates levels by in vitro fermentation,aiming to determine the fermentation pattern of protein by porcine colon microbiota. Porcine colon digesta was used as microbial inoculum,0（ group C）,0.10（ group L） and 0.25 g/L（ group H） casein was added into microbial fermentation broth. At different time points（ 3,6,9,12,18 and 24 h）,cumulative gas production,p H and concentrations of microbial crude protein,ammonia nitrogen and volatile fatty acid were determined. The results show ed as follow s： 1） at 3 and 5 h fermentation,the p H of group L and group H was significantly low er than that of group C（ P〈0.05）. 2） The cumulative gas production of group L and group H was higher than that of group C. 3） The concentration of microbial crude protein of group L and group H was significantly higher than that of group C at different time points（ P〈0.05）,and group H was significantly higher than group L at 6 h（ P〈0.05）. 4） The concentration of ammonia nitrogen of group L and group H was significantly higher than that of group C at different time points（ P〈0. 05）. 4） The concentrations of short-chain fatty acids and branched-chain fatty acids increased with the fermentation time,and increased with the protein level. The results suggest that adding protein substrates promotes intestinal microbial synthesis,but excessive protein cannot further increase microbial crude protein concentration,the microbial fermentation increases with protein level increasing.

关 键 词：蛋白质水平 猪 结肠微生物 发酵特性 菌体合成能力 

分 类 号：S816.17[农业科学—饲料科学]