Singh Ankit Kumar, Sharma Rajesh Kumar, Sharma Varsha, Singh Tanmay, Kumar Rajesh, Kumari Dimple
Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, Nanaji Deshmukh Veterinary Science University, Jabalpur - 482 001, Madhya Pradesh, India.
Department of Veterinary Microbiology, College of Veterinary Science and Animal Husbandry, Nanaji Deshmukh Veterinary Science University, Jabalpur - 482 001, Madhya Pradesh, India.
Vet World. 2017 May;10(5):510-516. doi: 10.14202/vetworld.2017.510-516. Epub 2017 May 11.
The objective of this study was to isolate endophytic bacteria from Azadirachta indica (neem) leaves, their identification and investigate their antibacterial activity against three Gram-positive bacteria, Staphylococcus aureus, Streptococcus pyogenes and Bacillus cereus and Gram-negative bacteria Escherichia coli, Salmonella Typhimurium and Klebsiella pneumoniae.
Fresh leaves of A. indica (neem) was procured from the Department of Botany, JNKVV, Jabalpur. Five samples were taken, and each sample was divided into five subsamples and separated for further isolation of endophytic bacteria. For sterilization leaves were treated with double distilled water, 0.1% sodium hypochlorite, 0.01% bavistin, 0.05% and 70% ethanol. Sterilized leaves of the plants were embedded in Kings B (KB) petri plates and incubated at 37°C for 24 h. Characterization of the bacteria was done according to its morphology and by Gram-staining. After that, a single colony was transferred into brain heart infusion (BHI) broth and incubated at 37°C for 24 h. The antibacterial effect was studied by the disk diffusion method with known antibiotic ciprofloxacin (Ci) as standard.
A total of 25 bacterial isolates from A. indica (neem) were obtained and identified morphologically. Most of the samples on KB media depicted irregular shape, flat elevation, undulated, rough, opaque, and white in color. Most of the samples on blood agar showed irregular, raise elevation, undulated, smooth, opaque and all the isolates were nonhemolytic and nonchromogenic. The growth of endophytic bacteria in BHI broth were all isolates showed turbidity. The microscopic examination revealed that maximum isolates were Gram-positive and rod shaped. Good antibacterial activity was observed against S. aureus, Streptococcus pyogenes, E. coli, Salmonella Typhimurium, and K. pneumoniae.
Endophytic bacteria are present in leaves of A. indica (neem) and it possesses antibacterial activity against few Gram-positive and Gram-negative bacteria.
本研究的目的是从印楝叶中分离内生细菌，对其进行鉴定，并研究它们对三种革兰氏阳性菌（金黄色葡萄球菌、化脓性链球菌和蜡样芽孢杆菌）以及革兰氏阴性菌（大肠杆菌、鼠伤寒沙门氏菌和肺炎克雷伯菌）的抗菌活性。
从贾巴尔普尔JNKVV植物学系获取新鲜的印楝叶。采集了五个样本，每个样本又分为五个子样本，用于进一步分离内生细菌。为进行灭菌处理，叶片用双蒸水、0.1%次氯酸钠、0.01%多菌灵、0.05%和70%乙醇处理。将植物的灭菌叶片接种于Kings B（KB）培养皿中，在37°C下培养24小时。根据细菌形态和革兰氏染色对其进行鉴定。之后，将单个菌落转接至脑心浸液（BHI）肉汤中，在37°C下培养24小时。以已知抗生素环丙沙星（Ci）为标准，采用纸片扩散法研究抗菌效果。
从印楝叶中共获得25株细菌分离株，并进行了形态学鉴定。KB培养基上的大多数样本呈现不规则形状、扁平凸起、边缘起伏、粗糙、不透明且为白色。血琼脂上的大多数样本呈不规则、凸起、边缘起伏、光滑、不透明，所有分离株均不溶血且不产色素。BHI肉汤中内生细菌的生长情况显示所有分离株均出现浑浊。显微镜检查显示，大多数分离株为革兰氏阳性且呈杆状。观察到对金黄色葡萄球菌、化脓性链球菌、大肠杆菌、鼠伤寒沙门氏菌和肺炎克雷伯菌具有良好的抗菌活性。
印楝叶中存在内生细菌，其对少数革兰氏阳性菌和革兰氏阴性菌具有抗菌活性。
