鹅肠道纤维分解菌的分离筛选及酶活力研究

Isolation and Enzyme Activity Determination of Cellulose-Decomposing Bacteria from Goose Intestinal Tract

从吉林白鹅回肠、盲肠内壁刮取物中分离筛选出4株纤维素分解细菌。在羧甲基纤维素钠、豆秆粉等组成的液体发酵培养基中菌株M6的最大酶活力达到51.4 U。酶的最适作用温度60℃,其中菌株M6产生的酶在pH 4时酶活力较高,而其他3株菌产生的酶在pH 6时酶活力较高。模拟鹅盲肠条件,将单菌株及复合系菌株分别接种到苜蓿、玉米秸秆及羊草中,发现接种H1×M2×M6菌株的苜蓿中的粗纤维降解率达到了7.87%。

Four strains of cellulose-decomposing bacteria were isolated from intestinal tract of Jilin White Geese. These bacteria demonstrated the highest enzyme activity （EA 51.4 U） in liquid fermented culture medium which consisted of carboxymethyl cellulose-Na and bean stem powder. The most moderate temperature for enzyme activity was 60℃. The isolated strain M6 showed the highest EA at pH 4.0, while the rest three isolated strains showed the highest EA at pH 6.0. All four strains exhibited ability of degrading crude fiber under experimental conditions. The single strain and compound-strains were respectively inoculated in alfalfa, corn straw and leymus chinensis. The highest crude fiber degradation rate was 7.87% in inoculated H1 x M2 x M6 strain alfalfa when the caecum condition was simulated.