马盲肠内容物对半纤维素和果胶的降解作用。

Degradation of hemicellulose and pectin by horse caecum contents.

Bonhomme-Florentin A

L.A. CNRS n degrees 138, Groupe de Zoologie et Protistologie, Aubiere, France.

Br J Nutr. 1988 Jul;60(1):185-92. doi: 10.1079/bjn19880087.

Abstract

Polysaccharide depolymerases and glycoside hydrolases involved in the breakdown of plant structural polysaccharides (hemicellulose and pectins) were monitored in three fractions of the liquid phase of horse caecum digesta: acellular fluid (AF), bacteria (B) and protozoa plus bacteria (PB). 2. Both bacteria and protozoa were found to be involved in the decomposition of pectic substances, with two enzymic activities: depolymerase (polygalacturonase, EC 3.2.1.15; and pectin lyase, EC 4.2.2.10) and esterase (pectinesterase, EC 3.1.1.11). The activity of the PB fraction was higher than that of B. 3. With hemicellulosic substrates, all three fractions showed a significant xylan endo-1,3-beta-xylosidase (EC 3.2.1.32) activity. Mannan was hardly broken down. 4. Galactomannan and arabinogalactan were broken down more extensively by the PB fraction than by the B fraction. Glycosidase activities (xylan 1,4-beta-xylosidase, EC 3.2.1.37 and alpha-L-arabinofuranosidase, EC 3.2.1.55) were also observed.

摘要

监测了马盲肠消化液液相的三个部分（无细胞液（AF）、细菌（B）和原生动物加细菌（PB））中参与植物结构多糖（半纤维素和果胶）分解的多糖解聚酶和糖苷水解酶。2. 发现细菌和原生动物均参与果胶物质的分解，具有两种酶活性：解聚酶（聚半乳糖醛酸酶，EC 3.2.1.15；和果胶裂解酶，EC 4.2.2.10）和酯酶（果胶酯酶，EC 3.1.1.11）。PB部分的活性高于B部分。3. 对于半纤维素底物，所有三个部分均显示出显著的木聚糖内切-1,3-β-木糖苷酶（EC 3.2.1.32）活性。甘露聚糖几乎不被分解。4. 半乳甘露聚糖和阿拉伯半乳聚糖被PB部分分解的程度比B部分更广泛。还观察到糖苷酶活性（木聚糖1,4-β-木糖苷酶，EC 3.2.1.37和α-L-阿拉伯呋喃糖苷酶，EC 3.2.1.55）。