Kaur Navdeep, Arora Daljit Singh
Microbial Technology Laboratory, Department of Microbiology, Guru Nanak Dev University, Amritsar, 143005, India.
AMB Express. 2020 Nov 11;10(1):206. doi: 10.1186/s13568-020-01143-y.
The current study prospects the antimicrobial potential of an endophytic fungus Chaetomium globosum which showed a wide spectrum antimicrobial activity against the tested pathogenic microorganisms. This is apparently the first report where Chaetomium globosum as an endophyte from Moringa oleifera showed antimicrobial potential and is optimized for physiochemical parameters to enhance the antimicrobial metabolites production. In the classical optimization yeast peptone dextrose medium, inoculum size of two discs, incubation period of 6 days, production temperature of 25 ºC and pH 7 was best supportive for optimal growth and antimicrobial activity whereas maltose and ammonium nitrate were the best carbon and nitrogen sources, respectively. The statistical optimization resulted in up to 1.33 fold increase in antimicrobial activity. Chloroform was found to be the best extractant. The chloroformic extract showed minimum inhibitory concentration ranging from 0.05 to 5 mg/ml and its microbicidal nature was established by viable cell count studies. The efficacy of the extract was also established in terms of post antibiotic effect which ranged from 2 to 20 h. The chloroformic extract exhibited the good antibiofilm potential and was also found to be biosafe. The clinical relevance of the study was justified as it showed good antimicrobial efficacy against some resistant clinical isolates, too.
本研究展望了内生真菌球毛壳菌的抗菌潜力，该菌对受试致病微生物表现出广谱抗菌活性。这显然是首篇报道，即来自辣木的内生球毛壳菌具有抗菌潜力，并针对理化参数进行了优化以提高抗菌代谢产物的产量。在经典优化的酵母蛋白胨葡萄糖培养基中，两个菌盘的接种量、6天的培养期、25℃的生产温度和pH 7最有利于最佳生长和抗菌活性，而麦芽糖和硝酸铵分别是最佳碳源和氮源。统计优化使抗菌活性提高了1.33倍。发现氯仿是最佳提取剂。氯仿提取物的最低抑菌浓度为0.05至5mg/ml，通过活菌计数研究确定了其杀菌性质。提取物的疗效也通过抗生素后效应得以确立，抗生素后效应为2至20小时。氯仿提取物具有良好的抗生物膜潜力，且被发现具有生物安全性。该研究的临床相关性得到了证实，因为它对一些耐药临床分离株也显示出良好的抗菌效果。
