Influence of rhamnolipids, produced by Pseudomonas aeruginosa NCAIM(P), B001380 on Cr(VI) removal capacity in liquid medium

Abstract

Pseudomonas aeruginosa NCAIM(P), B001380, a propitious bacterial strain isolated from mineral cutting oil was identified to be chromium tolerant and a producer of biosurfactant rhamnolipid (RL) with potential application in heavy metal bioremediation. Culture growth, RL production and Cr(VI) removal capacity of the strain in the presence of 50 mg L-1 (I) and 100 mg L-1 of Cr(VI) (II) were studied. Maximum of RL production were found in the late-stationary phase at 72 h for both Cr(VI)-amended cultures: I (236 mg L-1) and II (160 mg L-1), as well as the maximum of Cr(VI) removal capacity: 70 % (I) and 57 % (II). The amount of Cr in RL preparation II was 22 mg mg-1 determined by flame atomic absorption spectroscopy (FAAS). Appearance of a new band at 914 cm-1 in infrared (IR) spectrum of RL (II) indicated a significant proof for possible coordination of CrO42-ion with RL. The effect of Cr(VI) on monorhamnolipids (RL1) and dirhamnolipids (RL2) distribution and its ratio were studied by electrospray ionization mass spectrometry (ESI-MS). An increase was observed in a RL2/RL1 ratio for II compared to control

Efficient biodegradation of petroleum n-alkanes and polycyclic aromatic hydrocarbons by polyextremophilic Pseudomonas aeruginosa san ai with multidegradative capacity

“…23 P. aeruginosa san ai grows well in laboratory conditions, in media with alkaline pH up to 9.8, 23 it tolerates high concentrations of cadmium up to 7.3 mM, 22 and chromium up to 5.0 mM. 27 Consequently, P. aeruginosa san ai is an alkaliphilic and metallotolerant bacterium. 24 The isolate is deposited in NCAIM (National Collection of Agricultural and Industrial Microorganisms), Faculty of Food Sciences, Corvinus University of Budapest, Hungary, labeled as NCAIM B.001380 and in the public collection ISS WDCM 375 (Institute of Soil Science, Belgrade, Serbia) with accession number ISS 619.…”

Cadmium specific proteomic responses of a highly resistantPseudomonas aeruginosasan ai

“…15,16 P. aeruginosa san ai, an environmental isolate from mineral cutting oil, was previously used in various studies in our laboratory related to rhamnolipid, 17 exopolysaccharide (EPS), 18 the extracellular enzymes, lipase and protease, 19,20 and their application in detergents 21 as well as in the study related to the organism's capacity for chromium removal. 22 In this study, we investigated the distribution of cadmium, its uptake by extracellular polymers and effects of intracellular cadmium on protein expression in P. aeruginosa san ai. We used a global proteomic approach based on SEC protein prefractionation coupled with tandem mass spectrometry and bioinformatics to identify specic protein response to cadmium.…”

Rhamnolipid–Metal Ions (CrVI and PbII) Complexes: Spectrophotometric, Conductometric, and Surface Tension Measurement Studies

“…Avramovic et al (2013), with regard to the effect of chromium (VI) on mono‐ and di‐rhamnolipids in aqueous medium, indicated significant proof for a possible coordination of CrO 4 2− with protonated rhamnolipid by IR spectra. The present study has been carried out in neutral aqueous medium in which protonated rhamnolipid does not exist.…”