一株节杆菌溶解磷矿粉的动态

磷矿粉用量明显地影响节杆菌1TCRi7菌株对其溶解,随着磷矿粉用量的增加,溶磷率急剧下降,超过5 g/L,溶磷率不到0.1%,培养液的pH也随磷矿粉用量增加而升高,但菌体生长繁殖几乎不受磷矿粉用量的影响。振荡培养时,第1 d菌体繁殖量就达到高峰,pH也降至最低,同时表现出强烈的溶磷活力,但菌株的溶磷量并不与其生长量吻合,溶磷量第9 d才达到高峰,以后逐渐下降。培养过程中有机酸分泌发生交替变化,主要分泌乙酸和丙二酸。第1 d、第9 d和第15 d出现3个峰值,说明微生物利用了所分泌出来的有机酸,并发生了有机酸代谢的变化。

The Dynamics of Rock Phosphate Solubilization by an Arthrobacter 1TCRi7

Rock phosphate addition significantly affected the phosphate solubilization by Arthrobacter ITCRi7. The solubi-lization rate decreased sharply with increasing the rock concentration in the media. It was less than 0.1 % when the rock concentration was over 5g/L. The pH of the media also decreased with the increase of the rock concentration in the media. However, the bacterial growth wasn' t suppressed by adding a large amount of the rock. During 21d incubation, the bacterium reached to its maximal growth at the first day. At same time,the pH of the media was also reduced to the lowest level.The rock solubilization was not in line with the microbial growth. It reached to the maximum at the 9th d, and then decreased gradually. The organic acids, mainly acetic and malonic acids, changed alternatively.Three peaks of organic acid production were found at 1st, 9th and 15th d incubation, which implies that the bacterium utilized the acids and changed its strategy of organic acid metabolism.