Sharma Deepansh, Saharan Baljeet Singh, Chauhan Nikhil, Procha Suresh, Lal Sohan
Department of Microbiology, Kurukshetra University, Kurukshetra, 136 119 INDIA ; Dairy Microbiology Division, National Dairy Research Institute, Karnal, Haryana 132 001 India.
Department of Microbiology, Kurukshetra University, Kurukshetra, 136 119 INDIA.
Springerplus. 2015 Jan 7;4(1):4. doi: 10.1186/2193-1801-4-4. eCollection 2015.
The objective of the present study was to isolate the biosurfactant (BS) producing lactic acid bacteria (LAB) from traditional fermented food (buttermilk) and its functional and structural characterization. BS isolated from strain MRTL9 reduced surface tension from 72.0 to 40.2 mN m(-1). The critical micelle concentration (CMC) of BS was 2.25 mg ml(-1) with emulsification efficiency (E24) after 24 h of 64% against kerosene oil. The cell bound BS was partially purified by silica gel column chromatography and found as glycolipid. The gas chromatography and mass spectroscopy data revealed the fatty acid as hexadecanoic acid. Xylose was determined as hydrophilic moiety. The BS was found to be stable to pH changes over a range of 4.0-12.0, being most effective at pH 7 and showed no apparent loss of surface tension and emulsification efficiency after heat treatment at 120°C for 15 min. The outcomes of cellular toxicity showed lower toxicity of BS in comparison to SDS and rhamnolipids. Current study confirmed the preventive anti-adhesion activity of BS. These amphiphilic molecules, interferes with the microbial adhesion and found to be least cytotoxic with cellular compatibility with mouse fibroblasts cells.
本研究的目的是从传统发酵食品（酪乳）中分离出产生生物表面活性剂（BS）的乳酸菌（LAB），并对其进行功能和结构表征。从菌株MRTL9中分离出的BS将表面张力从72.0降低到40.2 mN m(-1)。BS的临界胶束浓度（CMC）为2.25 mg ml(-1)，24小时后对煤油的乳化效率（E24）为64%。细胞结合的BS通过硅胶柱色谱法进行部分纯化，发现为糖脂。气相色谱和质谱数据显示脂肪酸为十六烷酸。木糖被确定为亲水部分。发现BS在4.0-12.0的pH范围内对pH变化稳定，在pH 7时最有效，在120°C加热15分钟后表面张力和乳化效率没有明显损失。细胞毒性结果表明，与SDS和鼠李糖脂相比，BS的毒性较低。当前研究证实了BS的预防性抗粘附活性。这些两亲分子干扰微生物粘附，并且发现对细胞毒性最小，与小鼠成纤维细胞具有细胞相容性。
