Dong Qinglin, Dong Rongzhen, Xing Xiangying, Li Yukuan
a Department of Bioengineering, School of Chemical Engineering and Technology , Hebei University of Technology , Tianjin , P. R. China.
b Department of Applied Chemistry, School of Chemical Engineering and Technology , Hebei University of Technology , Tianjin , P. R. China.
Nat Prod Res. 2018 Jun;32(11):1348-1352. doi: 10.1080/14786419.2017.1343320. Epub 2017 Jun 19.
The culture broth of the cyanobacterium-symbiotic fungus Simplicillium lanosoniveum var. Tianjinienss Q. L. Dong exhibited unanticipated antibacterial activities against the Gram-positive bacteria, particularly the pathogenic bacterium Staphylococcus aureus, indicating the secretion of antibiotic-like metabolite, for which the modified Sabouraud medium was the suitable medium. The antibiotic-like metabolite was separated with macroporous resins CT-12 (absorption) and 95% ethanol (desorption), purified by ion-exchange resins D301T and displayed a characteristic absorption peak at 228 nm, suggesting the presence of nitrogen. The negative biuret and ninhydrin tests confirmed the absence of -NH and -COOH groups. Further, HPLC and mass spectrometry analyses showed that the retention time and molecular weight of the antibiotic-like metabolite were 4.1031 min and 163.0182 (Δ ± 2.3 ppm), respectively. Taking together, we speculated that the antibiotic-like metabolite was a new antibiotic structurally similar to alkaloid, which was the first one isolated from the species of Simplicillium genus.
蓝藻共生真菌天京简梗孢菌（Simplicillium lanosoniveum var. Tianjinienss Q. L. Dong）的培养液对革兰氏阳性菌，尤其是病原菌金黄色葡萄球菌表现出意想不到的抗菌活性，这表明其分泌了类似抗生素的代谢产物，改良的沙氏培养基是适合的培养基。用大孔树脂CT-12（吸附）和95%乙醇（解吸）分离出类似抗生素的代谢产物，通过离子交换树脂D301T进行纯化，该代谢产物在228 nm处显示出特征吸收峰，表明含有氮元素。双缩脲阴性和茚三酮试验证实不存在-NH和-COOH基团。此外，高效液相色谱和质谱分析表明，类似抗生素的代谢产物的保留时间和分子量分别为4.1031分钟和163.0182（Δ±2.3 ppm）。综合来看，我们推测该类似抗生素的代谢产物是一种结构类似于生物碱的新型抗生素，这是首次从简梗孢属物种中分离得到的。
