某些因子对四株维氏固氮菌菌株合成海藻酸的影响

Effects of some conditions on alginic acid syntliesised by 4 strains of Azolobacter vinelandii

本试验结果表明:相同条件下,四株维氏网氮菌（Azotobacter vinelandii）中,以菌株N13的发酵周期短（1～2天）,海藻酸合成最大（5.82 g/L）,产海藻酸活力强（活力系数为2.60）;不同条件下,菌株N13在所试菌龄内,海藻酸合成最均高于其他菌株,其一天菌龄的浓度高达5.45±0.43 g/L,不同发酸液的海藻酸合成最仅在pH 8.0时低于菌株14#,尤以pH6.0时,高达8.61g/L.在旋转式摇床或往复式摇床上,亦以菌株N13的海藻酸合成量最高（3.61±0.26 g/L和4.39±0.12 g/L）,试验温度范围内,也以菌株N13的海藻酸合成量最高,32℃时达到最大值（6.41 g/L）,菌株N13以2～8％（V/V）的接种量试验表明:旋转式摇床为2％,往复式摇床为2～4％。

Comparative experiment was conducted using 4 strains of A.vinelandii under the same conditions.It was shown that the fermentation time of strain N13 of A.vinelandii was the shortesl(1~2 days)among them.The bacterium had the highest alginic acid product(about 5.82g/l)and strongest alginic acid-produced activity(A/C =2.60).Comparative experiments among strains were conducted under different conditions.It was shown that strain Nl3 of A.vinelandii war,a highest productive alginic acid bacterium.Its alginic acid content was up to 5.45+/-0.43 g/L at the age of 1 day.The alginic acid content was especially about 8.61g/L at inital pH=6.0.Alginic acid producted by strain N13 was the highest both at the rotator and the reciprocal shaker(3.6l+/-0.20 and 4.39+/-0.12g/L respectively).At 32 C,its product was the highest,about 6.41g/L.The test was conducted on inoculum volumes at 2~8%(v/v).It.was shown than 2% were adequate at rotator,but 2~4% were sufficient at reciprocal shaker.