Microbiology Section, Centre for Advanced Studies in Animal Nutrition, Indian Veterinary Research Institute, Izatnagar, India.
Arch Anim Nutr. 2010 Aug;64(4):279-92. doi: 10.1080/17450391003625037.
Fermentative characteristics and fibrolytic enzyme activities of anaerobic gut fungi from wild (17 isolates) and domestic ruminants (15 isolates) were examined. In a medium containing 0.5% wheat straw and 0.02% cellobiose as energy source, activities of carboxymethyl cellulase (CMCase), avicelase, xylanase, acetyl esterase and protease produced by the fungal isolates were investigated. Average activity of CMCase (17.4 vs. 8.25 mIU ml(-1)), acetyl esterase (134 vs. 57 mIU ml(-1)) and protease (4400 vs. 1683 mIU ml(-1)) were significantly higher in isolates from wild ruminants than those from domestic ruminants. Xylanase and avicelase activities were comparable. When compared irrespective of source, fungal isolates having monocentric growth pattern produced more fibrolytic enzymes than isolates having polycentric growth pattern. CMCase, xylanase, avicelase activities were highest in Neocallimastix isolates. Acetyl esterase activity was highest in Piromyces and Neocallimastix isolates. Protease activity was highest in Piromyces isolates followed closely by Neocallimastix isolates. Between isolates from wild and domestic ruminants few differences were observed in pattern of carbohydrate utilisation and end products of fermentation. Inter-strain differences in the end product formation were apparent. All of the isolates produced acetate, lactate and formate; only a few isolates produced succinate. For isolation of superior fibrolytic isolates of anaerobic fungi, greater emphasis should be given to the screening of enzyme activities of isolates of genera Neocallimastix and Piromyces.
从野生（17 株）和家养反刍动物（15 株）的肠道真菌中筛选出具有发酵特性和纤维分解酶活性的菌株。在含有 0.5%小麦秸秆和 0.02%纤维二糖作为能源的培养基中，研究了真菌分离株产生的羧甲基纤维素酶（CMCase）、木聚糖酶、纤维素酶、乙酰酯酶和蛋白酶的活性。野生反刍动物来源的真菌分离株的 CMCase（17.4 比 8.25 mIU ml(-1)）、乙酰酯酶（134 比 57 mIU ml(-1)）和蛋白酶（4400 比 1683 mIU ml(-1)）活性均显著高于家养反刍动物来源的真菌分离株。木聚糖酶和纤维素酶活性相当。不论来源如何，具有单核生长模式的真菌分离株比具有多核生长模式的真菌分离株产生更多的纤维分解酶。Neocallimastix 分离株的 CMCase、木聚糖酶、纤维素酶活性最高。Piromyces 和 Neocallimastix 分离株的乙酰酯酶活性最高。Piromyces 分离株的蛋白酶活性最高，其次是 Neocallimastix 分离株。野生和家养反刍动物来源的分离株在碳水化合物利用模式和发酵终产物方面差异不大。菌株间的终产物形成存在明显差异。所有分离株均产生乙酸盐、乳酸盐和甲酸盐；只有少数分离株产生琥珀酸盐。为了分离出具有优越纤维分解能力的厌氧真菌分离株，应更加重视筛选 Neocallimastix 和 Piromyces 属分离株的酶活性。
