Production and characterization of di-rhamnolipid produced by Pseudomonas aeruginosa TMN

Abstract

-Pseudomonas aeruginosa TMN was used to produce rhamnolipid (RL) from a variety of carbon and nitrogen substrates. The most favorable carbon sources for RL production were glucose and glycerol (both at 40 g/L), giving a RL yield of 0.3 and 0.25 g/L, respectively. Meanwhile, sodium nitrate appeared to be the preferable nitrogen source, resulting in a RL production of 0.34g/L. Rhamnolipid production from P. aeruginosa TMN was affected by temperature, pH and agitation rate, with 37 °C, pH 7 and 200 rpm agitation favorable for rhamnolipid production. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and electro spray ionization-mass spectrometry (ESI-MS) analyses indicated that the purified product contained one type of commonly found rhamnolipid, which is L-rhamnosyl-L-rhamnosyl-β-hydroxydecanoyl-β-hydroxydecanoate. The rhamnolipid product can reduce the surface tension of water to 34 mN/m with a critical micelle concentration of nearly 18.75 mg/L and emulsified kerosene by 46%. P. aeruginosa TMN strain is a potential source of rhamnolipid biosurfactant, which could be used for the development of bioremediation processes in the marine environment.

The true methodology for rhamnolipid: Various solvents affect rhamnolipid characteristics

“…The bacterium was isolated from soils with hydrocarbon contaminated industrial zone and identified as a P. aeruginosa (ESOGÜ‐BK B 053). Seed culture was incubated in nutrient broth at overnight and then rhamnolipid production was performed in mineral salt medium (MSM) consisting of (g/L) NH 4 Cl 15 g, KH 2 PO 4 4.3 g, K 2 HPO 4 3.4 g, KCl 1.1 g, NaCl 1.1 g, yeast extract 0.5 g, CaCl 2 · 2H 2 O 0.24 g, ZnSO 4 · 7H 2 O 0.29 g, MnSO 4 · H 2 O 0.17 g, MgSO 4 · 7H 2 O 0.5 g. For this purpose, the seed culture (2% inoculum) was inoculated and incubated at 35°C and 150 rpm for 72 h. Carbon source for this medium was added as 20 g/L sucrose. The pH of mineral salt medium has not been adjusted.…”

“…The bacterium was isolated from soils with hydrocarbon contaminated industrial zone and identified as a P. aeruginosa (ESOG € U-BK B 053). Seed culture was incubated in nutrient broth at overnight and then rhamnolipid production was performed in mineral salt medium (MSM) consisting of (g/L) NH 4 [19,20] and incubated at 35°C and 150 rpm for 72 h. Carbon source for this medium was added as 20 g/L sucrose. The pH of mineral salt medium has not been adjusted.…”

EFFECTS OF CULTIVATION MEDIA COMPONENTS ON BIOSURFACTANT AND PIGMENT PRODUCTION FROM Pseudomonas aeruginosa PAO1

“…In this work complex media components for cultivation of P. aeruginosa PAO1 have been screened for identifying their specific roles to produce biosurfactant and pigment. Screening of components of complex cultivation media with statistical analysis helps us to understand the effects of each component on biomass growth, product formation and underlying metabolic changes responsible for such variation (Das et al, 2009;Moussa et al, 2014). As carbon source is essential for growth and product formation, glycerol was used since it is available in excessive amount at a cheap price as a by-product from the biodiesel industry (Xu et al, 2012).…”

Optimization of the Operating Conditions for Rhamnolipid Production Using Slaughterhouse-Generated Industrial Float as Substrate

“…Rhamnolipids are efficient in the bioremediation of soils polluted by oily compounds (Santa Anna et al, 2007). According to Pirollo (2006) and Moussa et al (2014), rhamnolipids consist of one or two rhamnose molecules and one or two fatty acid chains of 8 to 12 carbon atoms, which may be saturated or unsaturated.…”