Aneurinifactin, a new lipopeptide biosurfactant produced by a marine Aneurinibacillus aneurinilyticus SBP-11 isolated from Gulf of Mannar: Purification, characterization and its biological evaluation.

Biosurfactants are microbial-derived amphiphilic molecules having hydrophobic and hydrophilic moieties produced by bacteria, fungi, yeasts and algae and are extracellular or cell wall-associated compounds. In an ongoing survey for bioactive microbial metabolites from microbes isolated from diverse ecological niches, a new lipopeptide biosurfactant was identified from a marine bacterium; Aneurinibacillus aneurinilyticus strain SBP-11, which was isolated from a marine diversity hotspot, Gulf of Mannar, India. A new lipopeptide biosurfactant was purified and characterized based on TLC, FT-IR, NMR, GC-MS, HPLC, MALDI-TOF-MS and tandem MS analysis as Stearic acid-Thr-Tyr-Val-Ser-Tyr-Thr (named as Aneurinifactin). The critical micelle concentration of Aneurinifactin was 26mgL-1 at a surface tension of 26mNm-1. Further, the biosurfactant showed stable emulsification at a wide range of pH (2-9) and temperature up to 80°C. Aneurinifactin showed promising antimicrobial activity and concentration dependent efficient oil recovery. This is the first report on Aneurinifactin, a lipopeptide biosurfactant produced by a marine A. aneurinilyticus SBP-11, which could be explored as a promising candidate for use in various biomedical and industrial applications.

Balan SS ，Kumar CG ，Jayalakshmi S 《-》

Antimicrobial potential of a lipopeptide biosurfactant derived from a marine Bacillus circulans.

Das P ，Mukherjee S ，Sen R 《-》

High-performance liquid chromatography purification of biosurfactant isoforms produced by a marine bacterium.

Sivapathasekaran C ，Mukherjee S ，Samanta R ，Sen R ... -  《-》

Biofilm inhibition and antimicrobial action of lipopeptide biosurfactant produced by heavy metal tolerant strain Bacillus cereus NK1.

Biosurfactants are worthful microbial amphiphilic molecules with efficient surface-active and biological properties applicable to several industries and processes. Among them lipopeptides represent a class of microbial surfactants with increasing scientific, therapeutic and biotechnological interests. A heavy metal tolerant Bacillus strain has been isolated and the biofilm inhibition and antimicrobial activity of biosurfactant produced by the strain have been studied. Biosurfactant production was confirmed by the conventional screening methods including hemolytic activity, drop collapsing test, oil displacement test, emulsification and lipase production assays. The biosurfactant produced by this strain was a lipopeptide and exhibited strong surface activity. The biosurfactant has been characterized using FTIR, TLC and HPLC. The minimum active dose of this biosurfactant when compared with the other chemical surfactants was found as 0.150±0.06 μg. The critical micelle concentration was found to be 45 mg/l. The biosurfactant was found to be stable and active over a wide range of pH, temperature and NaCl concentration. It was also able to emulsify a wide range of hydrocarbons and oils thereby extending its application for the bioremediation of oil contaminated sites. The biosurfactant exhibited significant reduction in biofilm formation by pathogens and showed potent antimicrobial activity against various gram positive, gram negative bacteria and fungi. Agar diffusion assay for heavy metal resistance showed that the isolate was resistant to ferrous, lead and zinc. Considering the biofilm inhibition and antimicrobial property of biosurfactant, it can be utilized as a potential therapeutic molecule for numerous microbial infections. The heavy metal resistance of the strain can also be harnessed as an invaluable biological tool for in situ bioremediation.

Sriram MI ，Kalishwaralal K ，Deepak V ，Gracerosepat R ，Srisakthi K ，Gurunathan S ... -  《-》

First report of a lipopeptide biosurfactant from thermophilic bacterium Aneurinibacillus thermoaerophilus MK01 newly isolated from municipal landfill site.

Sharafi H ，Abdoli M ，Hajfarajollah H ，Samie N ，Alidoust L ，Abbasi H ，Fooladi J ，Zahiri HS ，Noghabi KA ... -  《-》