Yan Z, She X, Li M, Zhang S
Institute of Microbiology, Chinese Academy of Sciences, Beijing.
Chin J Biotechnol. 1992;8(3):211-8.
The authors isolated 1380 bacterial strains from 290 soil samples collected in China and 490 strains were received from other research teams in this institute. By screening 707 strains showed starch-hydrolyzing activity. By further screening and paper chromatographic test, three strains with maltotetraose as the major product were obtained. The maltotetraose was further confirmed by treatment with beta-amylase splitting to maltose and with glucoamylase to glucose. The most promising strain was 537.1, which produced maltotetraose about 90% (w/w) in the starch hydrolysate. While the other two strains produced maltose and maltotriose besides maltotetraose. Strain 537.1 was tentatively identified as Alcaligenes sp. The optimum conditions for enzyme production were as follows: medium composition: 1.5% maltose; 0.5% peptone with initial pH of 7.0-7.5; cultured at 27-28 degrees C for 48 hours on rotary shaker. The culture supernatant of the strain 537.1 can hydrolyze starch and different kinds of cereal flour with a high yield of maltotetraose in the hydrolysate.
作者从在中国采集的290份土壤样本中分离出1380株细菌菌株，另外490株菌株来自该研究所的其他研究团队。通过筛选，707株菌株显示出淀粉水解活性。经过进一步筛选和纸色谱试验，获得了三株以麦芽四糖为主要产物的菌株。通过用β-淀粉酶将其分解为麦芽糖以及用糖化酶将其分解为葡萄糖，进一步证实了麦芽四糖。最有前景的菌株是537.1，它在淀粉水解产物中产生的麦芽四糖约为90%（w/w）。而另外两株菌株除了产生麦芽四糖外，还产生麦芽糖和麦芽三糖。菌株537.1初步鉴定为产碱杆菌属。产酶的最佳条件如下：培养基组成：1.5%麦芽糖；0.5%蛋白胨，初始pH值为7.0 - 7.5；在旋转摇床上于27 - 28℃培养48小时。菌株537.1的培养上清液可以水解淀粉和不同种类的谷物粉，在水解产物中产生高产率的麦芽四糖。
