黄河中上游半干旱区典型盐渍土中细菌耐盐性及产酶特性研究

对陕西、宁夏和内蒙的典型盐渍土样分离得到180株细菌,在NaCl浓度为15%,20%,25%,30%,32%五个梯度进行了菌株耐盐性的试验。用平板检测法对菌株的纤维素酶、蛋白酶、淀粉酶和脂肪酶等4种水解酶产生情况进行了检测。结果表明:68.9%的菌株可在15%盐浓度的培养基中生长,随盐浓度增加,可生长的菌株数明显减少;在筛选出的耐盐菌中,来源于单一盐土中耐盐菌多于复合盐土,重盐土中筛出耐盐菌所占比例较大;供试菌株产蛋白酶和纤维素酶的能力高于产淀粉酶能力,其产脂肪酶的能力最弱。挑选出产纤维素酶和产蛋白酶效果较好的菌株各5株,并对其进行初步鉴定表明,大多数菌属于G ,杆状细菌,油脂状,不透明,并且表面光滑,耐15%盐浓度。

Study on Bacterial Salt Tolerance and Enzymatic Characteristic in Saline Alkal Soil of Shaanxi, Ningxia and Inner Mongolia

This experiment tested bacterial salt tolerance of 180 bacteria isolated from saline alkal soil in northwest of China at five NaCl concentration,15%,20%,25%, 30%,32%;and detect the ability of these strains to produce cellulase,protease,amylase and lipase inner plate.The results showed: about 68.9% strains can tolerant 15% NaCl concentration,the growable strains decreased significantly as the salt concentration increased;the strains enzyme produce ability decreased as protease,cellulase,amylase and lipase.Had a preliminary examination on the higher enzyme produce strains,generality are G~ ,bacilli,the colony is opacity and had slick surface,all these strains can tolerant 15% NaCl concentration.