Production of rhamnolipid biosurfactants by Pseudomonas aeruginosa DS10‐129 in a microfluidic bioreactor

Abstract

A low-cost microBR (microbioreactor) made from PTFE [poly(tetrafluoroethylene)] was used to cultivate a model organism, Pseudomonas aeruginosa DS10-129. The progress of bioprocessing was monitored by comparing the growth of the organism in a microBR, a conventional bench scale bioreactor and a shake flask. Under the microBR conditions, the organism produced 23 mg/ml of pyocyanin that had antimicrobial effects against Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas teessidea and Pseudomonas clemancea. Furthermore, it produced a total of 106 microg/ml of effective biosurfactants consisting of dirhamnolipids (RL2) and monorhamnolipids (RL1). The biosurfactants reduced the surface tension of distilled water from 72 to 27.9 mN/m and emulsified kerosene by 71.30%. The pyocyanin and rhamnolipids were produced during the exponential and stationary phases of growth respectively. The results of the microBR were comparable to those obtained using conventional scale methods.

Development and validation of an ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the quantitative determination of rhamnolipid congeners

“…DiRLs are generally the most abundant types of RLs produced (Monteiro et al 2007;Mata-Sandoval et al 2001;Samadi et al 2012;Rahman et al 2010) with only a few studies reporting mono-RLs as the predominant RL species (Arino et al 1996;Sim et al 1997). Some Pseudomonas strains have been reported to produce mono-RLs only (Zhang and Miller 1992;Gunther et al 2005).…”

Production of Biosurfactants Using Eco-friendly Microorganisms

“…Read et al ( 1992 ) also showed the presence of 65 μl/ml rhamnolipid in the secretions of a lung removed from a cystic fi brosis patient. The cytotoxic and haemolytic effects of crude rhamnolipids from other rhamnolipid producers have been demonstrated by researchers (Häussler et al 1998(Häussler et al , 2003Rahman et al 2010 ). Rhamnolipids have been shown to be heat-stable haemolysins having haemolytic activity on various erythrocyte species ( Fujita et al 1988 ;Johnson and Boese-Marrazzo 1980 ) and cytotoxic at high concentration to immune cells (Bjarnsholt et al 2005 ;Jensen et al 2007 ).…”

“…Novel natural producers of rhamnolipids identifi ed as P. clemancea nov. and P. teessidea nov. have been reported by Rahman et al ( 2010 ). Rhamnolipid production can be achieved with Pseudomonas sp.…”

A glycolipid biosurfactant from a native halophilic Bacillus species of Porto Novo, India and its potential microbially enhanced oil recovery properties

“…The presence of characteristic adsorption bands at 1377 cm -1 , 1458cm -1 , 2854 cm -1 , 2870 cm -1 , 2924 cm -1 and 2953 demonstrated the presence of aliphatic long hydrocarbon chain which was endorsed by Rahman et al (2010). The strong absorbance at 3401 cm -1 was considered as the characteristic peak of glycolipid biosurfactants (Li et al, 2002) which was assigned to the C-H stretching vibrations of the hydrocarbon chain positions.…”