Iron-Stimulated Production and Antimicrobial Potential of a Novel Biosurfactant Produced by a Drilling Waste-Degrading Pseudomonas citronellolis Strain

Abstract

A Pseudomonas citronellolis strain was isolated from drilling waste (DW). This strain utilizes DW as the sole energy and carbon source to produce biosurfactants (BSs). The BS produced was thermally stable, amorphous and includes a peptide structure. FeSO4, FeCl3 and Fe(NO3)3 were supplemented at various concentration levels to assess possible enhancement of BS production and DW biodegradation. The limit concentration of Fe compounds between the increase in BS formation and microbial toxicity was 0.1 mM. FeCl3 enhanced DW biodegradation and more than doubled the BS formation yield, determining an optimization strategy for BS production. The BS was then partially purified and used against several Gram-negative and positive multi-drug resistant bacteria (such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli spp, Acinetobacter baumaniii, Enterococcus faecalis spp, Streptococcus pneumoniae, Staphylococcus aureus, Salmonella enterica). The minimum inhibitory concentration was defined at a range of 0.25 to 10 mg/mL. The antimicrobial properties of the partially purified BS established its effectiveness and suggested a down-stream processing cost reduction, as no additional purification steps were necessary. The study could lead to a sustainable low-cost bioprocess towards a circular bioeconomy because waste, a non-expensive substrate, is used; while the BS holds great potential as a novel compound with antibiotic and disinfectant-like action, following toxicity testing with human cells.

Fertilization and Soil Microbial Community: A Review

“…Used for hydrocarbon biodegradation in contaminated soil, for plant pathogen elimination thanks to their antifungal, antiviral, insecticidal and antimycoplasma activities and for increasing the nutrient bioavailability for beneficial plant-associated microbes. [35][36][37] Compost Composting (biological decomposition under controlled moisture, self-heating and aerobic conditions) of animal manure, sewage sludge, municipal solid waste and green wastes Simplicity of technologies and possibility of implementation on every farm; quality protocols are provided in several countries for reducing pathogen, heavy metal and organic pollutant presence. [38,39] Green waste or biowaste Different origins: crop residues, food and kitchen waste.…”

Production and characterization of lipopeptide biosurfactant from a new strain of Pseudomonas antarctica 28E using crude glycerol as a carbon source

“…In the 2% (w/v) glycerol medium the substrate was utilized within 72 h, leading to the death of the culture. According to Tsipa et al 31 the borderline between iron deficiency and toxicity is narrow. Iron is a key component of cytochromes and contributes to the Krebs cycle.…”

“…FeSO 4 , Fe(NO 3 ) 3 and FeCl 3 , at the concentration of 0.1 mM, signicantly supports the growth and biosurfactant production of Pseudomonas citronellolis 620C. 31 Moreover, among the tested iron sources, the FeCl 3 supported the microbial growth to the greatest extent. The explanation is the highest solubility of FeCl 3 in comparison to Fe(NO 3 ) 3 and FeSO 4 .…”

Electricity generation and real oily wastewater treatment by Pseudomonas citronellolis 620C in a microbial fuel cell: pyocyanin production as electron shuttle

“…In this study, the electroactivity and biodegradation capability of P. citronellolis 620C; a strain recently isolated in our lab and shown to be highly capable of degrading oily wastewater [ 40 , 41 ], was assessed. The electroactivity and biodegradation ability of this P. citronellolis strain was tested in medium-sized double-chamber MFC, fed with oily wastewater (OW) as a substrate.…”