采用离子色谱(IC)分析了6种来源植物细胞壁的单糖组成种类及含量,并通过活体外产气量法研究了这6种植物细胞壁的发酵特征及其在反刍动物甲烷形成中的相对贡献。结果表明,不同植物细胞壁的单糖组成种类和数量显著不同。经体外发酵培养后,不同植物细胞壁的72h产气量(GP)、理论最大产气量(B)、产气速率(c)以及产气延滞期(1ag)均存在显著性差异(P值分别为〈0.0001,〈0.0001,0.0073和0.0002)。48h发酵产生的气体中,甲烷和CO。含量存在显著差异(P〈0.0001)。其中,以玉米秸细胞壁为底物时,气体中甲烷比例最高(22.21%),而以黑麦草细胞壁为底物时甲烷比例最低(8.94%)。6种来源植物细胞壁培养液中羧甲基纤维素酶(p--0.5316)和微晶纤维素酶(P一0.5063)活性差异不显著,而木聚糖酶活性则差异显著(P一0.0179)。不同来源植物细胞壁发酵产生的总挥发性脂肪酸量(TVFA)存在显著差异(P一0.0002),各种挥发性脂肪酸摩尔百分比除丁酸(P一0.468O)外均存在显著差异(P〈0.055)。不同类型植物细胞壁的单糖组成类型显著不同,其体外发酵特征及其对反刍动物甲烷形成的相对贡献存在显著性差异。
The types and the quantities of monosaccharide consisted in the six different plant cell walls were determined by the ion chromatograph in this experiment. And the ruminal fermentable characterization and the relative contribution to the methane yield in ruminant animals were compared with the six different plant cell walls by incubating them with the ruminal fluid as the method of gas production (Menke and Steingass, 1988). The gas production in 72 h, the maximum gas production, the rate and the lag time of gas production differed greatly among different plant cell walls (P value were %0. 000 1, %0. 000 1, 0. 007 3 and 0. 000 2, respectively). The percentage of methane and the carbon dioxide in the gas compostion differed significantly (P〈 0. 000 1). The activities of CMCase and Avicelase in the fermented fluid had no remarkable difference (P=0. 531 6 and 0. 506 3, respectively) but the xylanase activities were different greatly (P=0. 017 9). The total volatile fatty acid, the molar percentage of each kind of volatile fatty acid except butyrate (P=0.468 0) were different significantly (P〈0.055). It was concluded that the types and the quantities of monosaccharide consist in the six different plant cell walls and their ruminal fermentable characterization and the relative contribution to the methane yield in ruminant differed greatly.