Study on the isolation and fungicidal activities of diacetonamine in the fermentation broth of Streptomyces qinlingnensissp.nov

chinois. 对1株新放线菌――秦岭链霉菌中（Streptomyces qinlingnensis sp.nov）的抑菌活性成分进行研究。采用离子交换和硅胶柱层析，对秦岭链霉菌发酵液中的有效成分进行分离，并采用高分辨质谱和核磁共振技术对分离到的有效成分进行结构鉴定，采用抑制菌丝生长速率法测定有效成分对8种真菌的抑菌活性，采用管碟法进行8种细菌对有效成分的药敏性试验。从秦岭链霉菌发酵液中分离出了一个抑菌活性成分，鉴定为二丙酮胺，测定其对8种真菌和8种细菌的抑菌活性，结果表明，马铃薯干腐病菌、西瓜枯萎病菌和番茄早疫病菌对二丙酮胺相对比较敏感，其IC50值分别为49.57，85.08和74.69 μg/mL；蜡状芽孢杆菌和枯草芽孢杆菌对二丙酮胺相对敏感，当二丙酮胺质量浓度为31.3 μg/mL时，其抑菌圈直径分别为13和16 mm。对二丙酮胺的抑菌活性以前未见文献报道，其有可能作为一种抑菌活性先导化合物，或直接开发成农用杀菌剂

anglais. The objectvie of this research was to investigate the fungicidal components in the fermentation product of Streptomyces qinlingnensis sp.nov, a new actinomycete strain was isolated from the soil in Qinling mountain area. By ion-exchange and silica gel column chromatography, a fungicidal ingredient was isolated from the fermentation broth of the strain, and it was elucidated by HR MS and NMR. The fungicidal activity of this compound against 8 species of fungi was tested by the method of inhibition mycilium growth, and the sensetivity of this compound against 8 species of bateria was tested by cup-plate method. The fungicidal compound was isolated by HRMS and NMR as diacetonamine from Streptomyces qinlingnesis sp. nov, the fungicidal activities of diacetonamine against eight species of fungi and eight species of bacteria were tested. The results showed that Fusarium oxysporium, Fusarium azysporum and Alternaria Solani-were more sensitive to diacetonamine, the IC50 values of inhibiting mycelium growth were 49.57, 85.08 and 74.69 μg/mL, respectively. Diacetonamine could also inhibite Bacillus cereus and Bacillus subtills obviously, the diameter of inhibition zone at the concentration of 31.3 μg/mL were 13 and 16 mm, respecitvely. This was the first report about the fungicidal activity of the compound. It indicated that diacetonamine had the potential to become a candidate of agro-fungicide or a lead compound.