Gayal is a rare semi-wild bovine species found in the Indo-China. They can graze grasses, including bamboo leaves, as well as reeds and other plant species, and grow to higher mature live weights than Yunnan Yellow ca...Gayal is a rare semi-wild bovine species found in the Indo-China. They can graze grasses, including bamboo leaves, as well as reeds and other plant species, and grow to higher mature live weights than Yunnan Yellow cattle maintained in similar harsh environments. The aim of this study was to identify specific cellulase in the gayal rumen. A metagenomic fosmid library was constructed using genomic DNA isolated from the ruminal contents of four adult gayals. This library contained 38400 clones with an average insert size of 35.5 kb. The Umcel-1 gene was isolated from this library. Investigation of the cellulase activity of 24 random clones led to the identification of the Umcel-1 gene, which exhibited the most potent cellulase activity. Sequencing the Umcel-1 gene revealed that it contained an open reading frame of 942 base pairs that encoded a product of 313 amino acids. The putative gene Umcel-1 product belonged to the glycosyl hydrolase family 5 and showed the highest homology to the cellulase （GenBank accession no. YP_004310852.1 ） from Clostridium lentocellum DSM 5427, with 44% identity and 62% similarity. The Umcel-1 gene was heterologously expressed in Escherichia coil BL21, and recombinant Umcel-1 was purified. The activity of purified recombinant Umcel-1 was assessed, and the results revealed that it hydrolyzed carboxymethyl cellulose with optimal activity at pH 5.5 and 45~C. To our knowledge, this study provides the first evidence for a cellulase produced by bacteria in gayal rumen.展开更多
This experiment aimed to investigate the potential impact of supplementing different levels of black soldier fly(BSF)on growth performance,serum antioxidants,and ruminal microbiota of goats.Twenty-four native Anglo-Th...This experiment aimed to investigate the potential impact of supplementing different levels of black soldier fly(BSF)on growth performance,serum antioxidants,and ruminal microbiota of goats.Twenty-four native Anglo-Thai male goats(18.43±0.76 kg)were distributed across 4 dietary treatments with 6 repetitions in each group.The control treatment(BSF0)did not include BSF,the other treatments(BSF5,BSF10,and BSF15)contained 5%,10%,and 15%of BSF,respectively.Black soldier fly supplementation did not affect(P>0.05)growth performance.With increasing supplementation levels,the digestibility of dry matter(DM)decreased linearly and quadratically(P<0.05),while organic matter(OM)decreased linearly and quadratically(P<0.05).The apparent digestibility of crude protein(CP)decreased linearly(P<0.001),and neutral detergent fiber(NDF)and acid detergent fiber(ADF)decreased linearly and quadratically(P<0.05).Serum malondialdehyde concentration showed a linear(P<0.05)response at 0 h,while superoxide dismutase activity and 2,2-diphenyl-1-trinitrophenylhydrazine(DPPH)concentration exhibited linear responses(P<0.05)at 4 h.Black soldier fly supplementation did not affect(P>0.05)ruminal pH.In the BSF15 group,ruminal ammonia nitrogen(NH3–N)concentration decreased quadratically(P<0.001)at 0 h,and linearly(P<0.05)at 2 and 4 h.Acetic acid decreased linearly(P<0.05)at 2 and 4 h,propionic acid decreased linearly(P=0.029)at 4 h.However,the concentration of butyric acid significantly increased(P<0.05).Total volatile fatty acids(VFAs)were highest(P<0.05)in the BSF5 group,equal in BSF0 and BSF10,and lowest(P<0.05)in the BSF15 group.The supplementation of BSF did not affect(P>0.05)Chao 1,Shannon,and Simpson.The most abundant phylum were Bacillota,Bacteroidota,and Candidatus Saccharibacteria,the most abundant genera were Xylanibacter,Saccharibacteria,Butyrivibrio,and Ruminococcus,and there was no statistical difference(P>0.05)among the 4 treatments.In summary,supplementing with BSF did not affect the growth performance and ruminal microbiota of goats.It was noteworthy that the supplementation of BSF at 5%and 10%were beneficial,as they increased antioxidant levels and the concentration of short-chain fatty acids.In contrast,the supplementation of 15%BSF results in decreased digestibility,antioxidant levels,and VFA parameters.Therefore,we recommend limiting the addition of BSF in goat diets to no more than 10%.展开更多
基金supported by the National Natural Science Foundation of China (31160467, 31360562, 31160449 and 31260543)
文摘Gayal is a rare semi-wild bovine species found in the Indo-China. They can graze grasses, including bamboo leaves, as well as reeds and other plant species, and grow to higher mature live weights than Yunnan Yellow cattle maintained in similar harsh environments. The aim of this study was to identify specific cellulase in the gayal rumen. A metagenomic fosmid library was constructed using genomic DNA isolated from the ruminal contents of four adult gayals. This library contained 38400 clones with an average insert size of 35.5 kb. The Umcel-1 gene was isolated from this library. Investigation of the cellulase activity of 24 random clones led to the identification of the Umcel-1 gene, which exhibited the most potent cellulase activity. Sequencing the Umcel-1 gene revealed that it contained an open reading frame of 942 base pairs that encoded a product of 313 amino acids. The putative gene Umcel-1 product belonged to the glycosyl hydrolase family 5 and showed the highest homology to the cellulase （GenBank accession no. YP_004310852.1 ） from Clostridium lentocellum DSM 5427, with 44% identity and 62% similarity. The Umcel-1 gene was heterologously expressed in Escherichia coil BL21, and recombinant Umcel-1 was purified. The activity of purified recombinant Umcel-1 was assessed, and the results revealed that it hydrolyzed carboxymethyl cellulose with optimal activity at pH 5.5 and 45~C. To our knowledge, this study provides the first evidence for a cellulase produced by bacteria in gayal rumen.
基金supported by the National Research Council of Thailand (NRCT) and Suranaree University of Technology (SUT) project code NRCT5-RSA63009-01the Suranaree University of Technology scholarship for External Grants and Scholarships for Graduate Students (SUT-OROG scholarship) as a source of funding
文摘This experiment aimed to investigate the potential impact of supplementing different levels of black soldier fly(BSF)on growth performance,serum antioxidants,and ruminal microbiota of goats.Twenty-four native Anglo-Thai male goats(18.43±0.76 kg)were distributed across 4 dietary treatments with 6 repetitions in each group.The control treatment(BSF0)did not include BSF,the other treatments(BSF5,BSF10,and BSF15)contained 5%,10%,and 15%of BSF,respectively.Black soldier fly supplementation did not affect(P>0.05)growth performance.With increasing supplementation levels,the digestibility of dry matter(DM)decreased linearly and quadratically(P<0.05),while organic matter(OM)decreased linearly and quadratically(P<0.05).The apparent digestibility of crude protein(CP)decreased linearly(P<0.001),and neutral detergent fiber(NDF)and acid detergent fiber(ADF)decreased linearly and quadratically(P<0.05).Serum malondialdehyde concentration showed a linear(P<0.05)response at 0 h,while superoxide dismutase activity and 2,2-diphenyl-1-trinitrophenylhydrazine(DPPH)concentration exhibited linear responses(P<0.05)at 4 h.Black soldier fly supplementation did not affect(P>0.05)ruminal pH.In the BSF15 group,ruminal ammonia nitrogen(NH3–N)concentration decreased quadratically(P<0.001)at 0 h,and linearly(P<0.05)at 2 and 4 h.Acetic acid decreased linearly(P<0.05)at 2 and 4 h,propionic acid decreased linearly(P=0.029)at 4 h.However,the concentration of butyric acid significantly increased(P<0.05).Total volatile fatty acids(VFAs)were highest(P<0.05)in the BSF5 group,equal in BSF0 and BSF10,and lowest(P<0.05)in the BSF15 group.The supplementation of BSF did not affect(P>0.05)Chao 1,Shannon,and Simpson.The most abundant phylum were Bacillota,Bacteroidota,and Candidatus Saccharibacteria,the most abundant genera were Xylanibacter,Saccharibacteria,Butyrivibrio,and Ruminococcus,and there was no statistical difference(P>0.05)among the 4 treatments.In summary,supplementing with BSF did not affect the growth performance and ruminal microbiota of goats.It was noteworthy that the supplementation of BSF at 5%and 10%were beneficial,as they increased antioxidant levels and the concentration of short-chain fatty acids.In contrast,the supplementation of 15%BSF results in decreased digestibility,antioxidant levels,and VFA parameters.Therefore,we recommend limiting the addition of BSF in goat diets to no more than 10%.
