Production of Biosurfactants by Hydrocarbons degrading bacteria isolated from Soummam watershed Sediments of Bejaia in Algeria

Abstract

Hydrocarbons degrading bacteria were isolated from sediments of the Soummam watershed of Bejaia (Algeria). Eleven bacteria strains were isolated using an enrichment technique, method in mineral salt medium, with various hydrocarbons as the sole carbon source. The biodegradation confirmation of various hydrocarbons by these isolates was tested by hole-plate diffusion technique. Out of eleven cultures, nine had shown the growth around the holes. The isolates were screened for biosurfactant producing using oil spreading test and emulsification activity. The value of emulsification activity varied from 55.7 6 1.1 to 78.5 6 0.5%. The diameter of clear zone obtained varied between 20.7 6 1.2 mm and 33.7 6 1.2 mm, it was hence important compared to the negative control. Five bacterial strains were identified as Alcaligenes faecalis, Ochrobactrum, Cellulosimicrobium, Pseudomonas stutzeri, and Rhodococcus ruber by using physiochemical characterization and MALDI-TOF mass spectrometry tools. The best production of crude biosurfactant by the identified bacterial strains was found in R. ruber which produced 6.7 6 0.1 g/L of the crude biosurfactant after 168 h incubation in mineral salt medium (MSM) supplemented with 2% of glucose and 0.1 g/L of yeast extract. The biosurfactant produced by all bacterial strains showed a high emulsification index (E 24 ), where P. stutzeri revealed the highest one (92.2 6 1.1%).

The petroleum-degrading bacteria Alcaligenes aquatilis strain YGD 2906 as a potential source of lipopeptide biosurfactant

“…Petroleum-degrading bacteria enrichment and isolation were carried out according to the method reported by [8]. In brief, 10gfresh sediments from Soummam river Skala Bridge in Bejaia, Algeria, which was contaminated with different petroleum derivates, was added to a 500 ml flat bottle containing 100 ml physiological saline (1% NaCl) and subjected to vigorous agitation for 1-2 h and let stand for 1 h afterwards.…”

“…Five ml of the supernatant were transferred into Erlenmeyer flasks containing 45 ml Mineral Salt Medium (MSM),containing 3.0 g/L of Na2HPO4, 1.0 g/L of NH4NO3, 30 g/L of NaCl, 0.7 g/L of MgSO4.7H2O, 2.0 g/L of KH2PO4 and 1.0 ml of trace element solution. The trace element solution contained: 10 mg/L of ZnSO4.7H2O, 0.50 mg/L of CuSO4.5H2O, 0.50 mg/L of MnSO4.H2O, 20 mg/L of CaCl2 and30 mg/L of FeCl3.This culture medium was supplemented by 2% (v/v) of crude petroleum as an energy and carbon source to enrich petroleum-degrading microbial strains [8]. Afterward, flasks were incubated at 30 °C on a shaker at 150 rpm for 7 days.…”

Biodegradation potential of crude petroleum by hydrocarbonoclastic bacteria isolated from Soummam wadi sediment and chemical-biological proprieties of their biosurfactants

“…The strains were characterized as Alcaligenes faecalis, Cellulosimicrobium sp., and Rhodococcus ruber on the basis of phenotypic characterization and identification by MALDI-TOF Mass Spectrometry. Detection of biosurfactants production by these isolates was carried out by oil spreading test and measuring the emulsification index (E24) and were maintained as described previously (Yalaoui-Guellal et al, 2018).…”

“…The MSM containing 2% (v/v) of glucose and 0.1 g/L of yeast extract was used as the culture medium for biosurfactant production experiments. Biosurfactant production was carried out as described in our previous study (Yalaoui-Guellal et al, 2018). for the detection of compounds with free amino groups for the lipopeptide system.…”

Urbanization and risks: case of Bejaia city in Algeria

“…Household sewage was also discharged into rivers like into an open pit. The other industrial zones of Akbou, Sidi Aiche and El Kseur, which move away from Bejaia 60, 40 and 25km respectively, also discharge their untreated waste, brought to Bejaia by the great river of Soummam (Yalaoui-Guellal et al, 2018). This river pollutes in its turn the sea.…”