Indigenous Bacterial Consortium Research Articles

Biodecolorization of azo dye mixture (Remazol Brilliant Violet 5R and Reactive Red 120) by indigenous bacterial consortium isolated from dye contaminated soil

Biodecolorization of azo dye mixture (Remazol Brilliant Violet 5R and Reactive Red 120) by indigenous bacterial consortium isolated from dye contaminated soil

Petroleum hydrocarbon-contaminated soil bioremediation assisted by isolated bacterial consortium and sophorolipid.

Pollution in soil by petroleum hydrocarbon has become a global environmental problem. The bioremediation of petroleum hydrocarbon-contaminated soil was enhanced with the combination of an isolated indigenous bacterial consortium and biosurfactant. The biodegradation efficiency of total petroleum hydrocarbon (TPH) was increased from 12.2% in the contaminated soil to 44.5% and 57.7% in isolated consortium and isolated consortium & 1.5g sophorolipid (SL)/kg dry soil, respectively. The half-life of TPH degradation process was decreased from 32.5d in the isolated consortium reactor to 20.4d in the isolated consortium & 1.5g SL/kg dry soil. The addition of biosurfactant into contaminated soils improved the TPH desorption from solid matrix to the aqueous solution and the subsequent solubilization, which ultimately improved the bioavailability of TPH in contaminated soils. Biosurfactant also served as carbon sources which contributed to the stimulation of cell growth and microbial activity and accelerated the biodegradation process via co-metabolism. The enzyme activities and quantities of functional genes were demonstrated to be incremented in SL reactors. The biosurfactant improved the TPH bioavailability, stimulated the microbial activities and participated in the co-metabolism. The combination of bioaugmentation and SL benefitted the bioremediation of petroleum hydrocarbon-contaminated soil.

Biodegradation of total petroleum hydrocarbons in contaminated soils using indigenous bacterial consortium

Background: Biodegradation of hydrocarbon compounds is a great environmental concern due to their toxic nature and ubiquitous occurrence. In this study, biodegradation potential of oily soils was investigated in an oil field using indigenous bacterial consortium. Methods: The bacterial strains present in the contaminated and non-contaminated soils were identified via DNA extraction using 16S rDNA gene sequencing during six months. Furthermore, total petroleum hydrocarbons (TPH) were removed from oil-contaminated soils. The TPH values were determined using a gas chromatograph equipped with a flame ionization detector (GC-FID). Results: The bacterial consortium identified in oil-contaminated soils (case) belonged to the families Halomonadaceae (91.5%) and Bacillaceae (8.5%), which was significantly different from those identified in non-contaminated soils (control) belonging to the families Enterobacteriaceae (84.6%), Paenibacillaceae (6%), and Bacillaceae (9.4%). It was revealed that the diversity of bacterial strains was less in oil-contaminated soils and varied significantly between case and control samples. Indigenous bacterial consortium was used in oil-contaminated soils without need for amplification of heterogeneous bacteria and the results showed that the identified bacterial strains could be introduced as a sufficient consortium for biodegradation of oil-contaminated soils with similar texture, which is one of the innovative aspects of this research. Conclusion: An oil-contaminated soil sample with TPH concentration of 1640 mg/kg was subjected to bioremediation during 6 months using indigenous bacterial consortium and a TPH removal efficiency of 28.1% was obtained.

Bioremediation of petroleum hydrocarbons by vermicomposting process bioaugmentated with indigenous bacterial consortium isolated from petroleum oily sludge.

Finding a sound ecological-based approach for the removal of petroleum hydrocarbons (PHCs) from petroleum oily sludge (POS) generated in oil refinery plants is still a challenge. This study investigated the removal of total petroleum hydrocarbons (TPHs) using bioaugmentated composting (BC) by hydrocarbon-degrading bacteria (HDB) and vermicomposting (VC) by Eisenia fetida, individually and in combination (BCVC). After isolating two native bacterial strains from POS prepared from an oil refinery plant in Iran, the degradation capability of their consortium was initially assessed in mineral Bushnell-Haas medium (MBHM). Then, the biodegradation rates of POS in the BC, VC, and BCVC treatments containing different concentrations of TPHs (5, 10, and 20g/kg) were determined by measuring TPHs before and after the biodegradation. The results showed that the consortium degraded 20-62% of TPHs contents of Kerosene (1-5%) in the MBHM after 7 days. After 12 weeks, the TPHs removal percentages in the BC, VC, and BCVC treatments were respectively found to be 81-83, 31-49, and 85-91 indicating the synergistic effect of bacteria and worms in bioremediation of POS. The PHCs biodegradation in the BC, VC, and BCVC experiments was fitted to 1st order model kinetics. The results of toxicity tests indicated that the values of the no observed lethal concentration (NOLC) and median lethal concentration (LC50) of TPHs were 2-5 and 14.64g/kg, respectively after 28 days of earthworm exposure. Morphological impairments such as swelling, coiling, and curling were observed when TPHs concentration was even lower than NOLC. The study verified the effectiveness of vermicomposting bioaugmentated with the indigenous bacterial consortium for POS bioremediation.

Effect of Indigenous Microbial Consortium on Bioleaching of Arsenic from Contaminated Soil by Shewanella putrefaciens

The effects of indigenous microbial consortium on removal of As from As-contaminated soil using an Fe(III)-reducing bacterium Shewanella putrefaciens were investigated under circumneutral pH condition. Sequential extraction of As revealed that more than 30% of As was associated with Fe(III)-(oxy)hydroxides in the soil. Bioleaching experiments were conducted anaerobically with a supply of lactate as a carbon source. The highest As removal efficiency (57.5%) was obtained when S. putrefaciens and indigenous bacterial consortium coexisted in the soil. S. putrefaciens and indigenous bacteria solely removed 30.1% and 16.4% of As from the soil, respectively. The combination of S. putrefaciens and indigenous bacteria led to a higher amount of labile As after microbial dissolution of Fe(III)-(oxy)hydroxides. After microbial treatment, soil quality represented by pH and organic content appeared to be preserved. The results indicated that the ecological and physiological understanding of the indigenous microbiome might be important for the efficient application of bioleaching technology to remove As from contaminated soils.

Bioremediation of diesel oil in marine environment

Natural gas emissions from oil spill ensue changes to microbial consortia in oceans which might cause ecotoxicological impacts on marine life. Gas flaring, a technique in the clean-up of oil spill, is a major source of greenhouse gas emission and possess high risk of fire hazard. It is of utmost importance to avoid flaring and resort to cleaner techniques such as bioremediation. The study focuses on bioremediation of marine oil spill by indigenous bacterial consortia using beeswax as a biostimulant which supplements the limiting nutrients such as nitrate and phosphate. The experimental study was conducted by adding diesel oil in marine water with beeswax for bioremediation. The vital parameters such as dissolved oxygen, pH, diesel range organics, total microbial count, nitrate and phosphate contents were measured at intervals of 5 days. The indigenous bacteria utilized oil as carbon source and beeswax as nutrient source for growth and metabolism. The results showed 87% removal of oil content in treatment sample while only 59% reduction was achieved in the corresponding control sample. Evaporation of oil results in formation of aerosols and black carbon which can lead to climate change. The study proves that bioremediation of marine oil spill is an environmentally benign clean-up technique for oil spill which can reduce carbon emission.

A PAH-degrading bacterial community enriched with contaminated agricultural soil and its utility for microbial bioremediation

A bacterial community was enriched with polycyclic aromatic hydrocarbons (PAHs) polluted soil to better study PAH degradation by indigenous soil bacteria. The consortium degraded more than 52% of low molecular weight and 35% of high molecular weight (HMW) PAHs during 16 days in a soil leachate medium. 16S rRNA gene high-throughput sequencing and quantitative polymerase chain reaction analyses for alpha subunit genes of ring-hydroxylating-dioxygenase (RHDα) suggested that Proteobacteria and Actinobacteria at the phylum level, Pseudomonas, Methylobacillus, Nocardioides, Methylophilaceae, Achromobacter, Pseudoxanthomonas, and Caulobacter at the generic level were involved in PAH degradation and might have the ability to carry RHDα genes (nidA and nahAc). The community was selected and collected according to biomass and RHDα gene contents, and added back to the PAH-polluted soil. The 16 EPA priority PAHs decreased from 95.23 to 23.41 mg kg−1 over 35 days. Compared with soil without the introduction of this bacterial community, adding the community with RHDα genes significantly decreased soil PAH contents, particularly HMW PAHs. The metabolic rate of PAHs in soil was positively correlated with nidA and nahAc gene contents. These results indicate that adding an indigenous bacterial consortium containing RHDα genes to contaminated soil may be a feasible and environmentally friendly method to clean up PAHs in agricultural soil.

Decolorization and detoxification of Direct Blue 2B by indigenous bacterial consortium

Azo dyes are widely used in the textile industry despite being poorly biodegradable and highly toxic. Hence, azo dyes need to be removed from effluent prior to environmental discharge. Microbial communities are efficient for the degradation and mineralization of azo dyes. However, little is known about the functional microbial communities responsible for the degradation process. In this study, a novel indigenous bacteria consortium was developed for characterizing the functional microbial communities involved in the degradation of a sulfonated azo dye, Direct Blue 2B (DB2) in a simple batch reactor. The optimal temperature, pH, and salinity for the decolorization process were 38.70 °C, pH 7.57, and 20.10 g L−1 NaCl, respectively. The effect of the operating conditions on microbial community structure were determined using high-throughput Illumina HiSeq sequencing. Gammaproteobacteria, Betaproteobacteria, and Bacilli were dominant under most of the operating conditions. At pH above 8 and NaCl concentration above 30 g L−1, Firmicutes relative abundance did not significantly change suggesting tolerance towards alkaline and hypersaline environments. Tritium aestivum and Glycine max seed germination following exposure to YHK treated DB2 solution was above 80% compared to 50% in untreated DB2 solution. The YHK consortium decolorized dyes structurally different from DB2 such as trimethyl phenyl and direct dyes. The results of this study offer valuable data on improving optimization of dye biodegradation processes and the capability of YHK in in situ bioremediation.

Microbial degradation of Pyrazine Compounds in Wastewater and cow dung SouthwestNigeria.

Wastewater samples, industrial effluents from food industry and cow dung were obtained aseptically and the physico-chemical properties were determined following standard procedures. Serial dilution technique was used in isolating native pyrazine - degraders from composite wastewater and cow dung samples obtained from Agbara and Apapa wastewater treatment plant (WTP) as well as Agege and Agbara Abattoirs respectively. Nutrient agar and Mineral salt medium supplemented with (3%) Pyrazine-2-carboxamide were used for enrichment for the isolates. Standard and conventional methods were used for the characterization and identification of pyrazine degraders. Gas chromatography (GC) flame ionization detector (FID) was used to determine the degree of mineralization of pyrazine. The mean pyrazine-degrader count from wastewater samples was 1.1×106 cfu/ml while that of cow dung was 9.7×105 cfu/ml. The GC peaks revealed that the initial quantity of pyrazine (15mg/l) was mineralized leaving behind (0.175mg/l) residues after 21 days of its introduction. The bacterial genera found utilizing pyrazine as source of C and N energy includes; Bacillus sp.,Flavobacterium sp.,Corynebacterium sp., Pseudomonas sp.,Streptococcus sp. and Staphylococcus sp. The biodegradability of pyrazine by tropical indigenous bacterial consortium was established and the convincing evidence of its mineralization was with gas chromatography. The objectives of the current study was to isolate and identify indigenous pyrazine-degraders from tropical wastewater and cow dung.

Laboratory Investigation of Indigenous Consortia TERIJ-188 for Incremental Oil Recovery.

Bacterial Profile modification is an efficient process which brings the alteration in permeability of the porous media of the reservoir by selective plugging which eventually recover the residual oil. It is an advantageous and feasible method for residual oil recovery from high permeability zones of the reservoir. In this study, indigenous bacterial consortia, TERIJ-188 was developed from Gujarat oil fields. TERIJ-188 was identified as Thermoanaerobacter sp., Thermoanaerobacter brockii, Thermoanaerobacter italicus, Thermoanaerobacter mathranii, Thermoanaerobacter thermocopriae. The novelty of consortia was that it produces biomass (850 mg l-1), bio-surfactant (500 mg l-1), and volatile fatty acids (495 mg l-1) at 70°C in the span of 10 days, which are adequate to alter the permeability and sweep efficiency of high permeability zones facilitating the displacement of oil. The biosurfactant was analyzed for its functional group by FTIR and NMR techniques which indicate the presence of C-N bond, aldehydes, triacylglycerols. TERIJ-188 showed an effective reduction in permeability at residual oil saturation from 28.3 to 11.3 mD and 19.2% incremental oil recovery in a core flood assay. Pathogenicity test suggested that TERIJ-188 is non-toxic, non-virulent and safe for field implementation.

Synergistic degradation of crude oil by indigenous bacterial consortium and exogenous fungus Scedosporium boydii

The purpose of this study was to investigate the potential of defined co-culture of indigenous bacterial consortium and exogenous fungus Scedosporium boydii for biodegradation of crude oil. After 7 days of incubation, residual oil, n-alkanes and aromatic fraction were analyzed. The degradation rate of crude oil was increased from 61.06% to 81.45% by the defined co-culture according to the 3:1 inoculation ratio of bacteria to fungi. The microbial activity was enhanced markedly and the formation of biofilms was accelerated after suitable inoculation of Scedosporium boydii. High throughput analysis showed that bacterial evenness and diversity were increased and the relative abundance of Paraburkholderia tropica was increased observably from 7.67% to 56.13% in the defined co-culture. These results indicated that synergistic degradation of crude oil in the bacteria-fungi consortium may be advantageous for bioremediation of petroleum-contaminated site.

Microaerophilic decolorization of a textile dye C.I. Reactive Red 31 by indigenous bacterial consortium: Process optimization and enzymatic mechanism

Microaerophilic decolorization of a textile dye C.I. Reactive Red 31 by indigenous bacterial consortium: Process optimization and enzymatic mechanism

BIOREMEDIATION OF CONTAMINATED WASTE BY CADMIUM (Cd) IN WATERS USING INDIGEN BACTERIUM WITH EX-SITU WAY

<p><em>The bioremediation technique </em><em>for</em><em> a contaminated liquid waste of heavy metals using indigen</em><em>ous</em> bacteria is a convenient alternative to steps continues to be developed. The research aims to find out the effectiveness of an indigenous bacterial consortium<em></em><em> in bioremediation of contaminated liquid waste </em><em>by</em><em> cadmium </em><em>by</em><em> ex-situ. Experiments </em><em>were</em><em> arranged in RAL made in ex-situ where a liquid waste industry was given five treatments, namely control and four indigen</em><em>ous</em><em> bacterial consortia (A, D, E, and J) obtained from the isolation of bacteria originating from cadmium-contaminated of waste in Pasuruan </em><em>district</em><em>. Furthermore conducted observations of BOD<sub>5</sub>, COD, d.o. and Cd for seven days to find out the effectiveness of bioremediation. The results showed the four </em><em>indigenous </em><em>bacteria consortia have the bioremediation ability to reduce levels of </em><em>cadmium, </em><em>BOD<sub>5</sub>, COD, and increasing levels of DO. Indigen</em><em>ous</em><em> bacterial consortia D </em><em>has</em><em> the </em><em>best </em><em>ability of liquid industrial waste bioremediation </em><em>by</em><em> ex-situ. Indigen</em><em>ous</em><em> bacteria</em><em>l</em><em> consortia J </em><em>has</em><em> the </em><em>best of </em><em>capacity reduction levels of cadmium, </em><em>then the other of </em><em>indigen</em><em>ous</em><em> bacteria</em><em>l </em><em>consortia.</em><em></em></p><strong><em>Keywords:</em><em> indigenous bacterial, bioremediation, ex-situ, cadmium, liquid waste.</em></strong>

Paediatric health significance of prevalent stratified indigenous Lactobacillus spp. species in diet-dependent infantile faecal specimens

Background Composition of early gut microbiome changes in breast-fed and formula-fed infants as solids foods are introduced into their diet. Objective This study aims to investigate the stratified of easily culturable indigenous Lactobacillus spp. with probiotic potentials in infant faecal specimens. Participants and methods Questionnaires were administered on 41 healthy and well-nourished neonates and infants between 1.5 and 11 months of age through their mothers. Isolated bacterial florae were identified using standard phenotypic cultural and taxonomic procedures and tools. Results Most of the infants were fed on breast milk and industrial baby cereal foods; however, more male babies (seven) were exclusively breast-fed than female babies (two). The pH range of the infantile faecal specimens was 4.8–5.9, but the enumerated viable counts as colony-forming units were between 1.1 × 103 and 7.2 × 103 cfu g-1. No lactobacilli were isolated from 39% faecal specimens of 4–16 days old infants, but there were higher recovery rates of Lactobacillus strains from faecal specimens of older (5–11 months) infants. Diversity of isolated 151 Lactobacillus strains included one or more different phenotypes characterized as Lactobacillus acidophilus, Lactobacillus bifidus, Lactobacillus brevis, Lactobacillus casei, Lactobacillus plantarum and Lactobacillus reuteri. The overall most-prevalent Lactobacillus strains were L. reuteri (46.4%), L. casei (23.2%) and L. acidophilus (19.9%), whereas L. bifidus (7.28%), L. brevis (1.99%) although L. plantarum (1.32%) were isolated from faecal specimens of healthy infants above 5 months of age. L. acidophilus (32.5%), L. casei (26.0%), L. reuteri (31.2%) vs. L. casei (20.0%) and L. reuteri (62.7%) were the most-prevalent phenotypes from female and male babies, respectively. Conclusion Diet-dependent Lactobacillus spp., which reflected rich indigenous infantile bacterial consortium, were recoverable from faeces of less than 12-month-old breast milk-fed and industrial cereal-fed, healthy Nigerian infants without antibiotherapy.

Evaluation of Nitrogen Fixing Enzyme Activities in Response to Pyrene Bioremediation Efficacy by Defined Artificial Microalgal-Bacterial Consortium of Gujarat, India

ABSTRACTThis study was carried out to investigate the response and relationship between nitrogen fixing enzymes during the remediation of different concentrations of high molecular weight four rings Polynuclear Aromatic Hydrocarbon (PAH) Pyrene by microalgae Synechocystis sp. (cyanobacteria) with artificial developed indigenous bacterial consortium. One axenic microalgal culture of Synechocystis sp. and two pyrene degrading indigenous bacteria with efficient removal capabilities viz. Pseudomonas indoxyladons and Bacillus benzoevorans isolated from crude oil polluted site and common industrial effluent canal were used to construct the consortium. The effect of pyrene on algal growth in terms of chlorophyll-a was measured and it was found that in the presence of bacteria, the growth and bioremediation capacity of Synechocystis sp. raised tremendously, whereas Synechocystis sp. monoculture exhibited concentration dependent decrease. Moreover, the nitrogen fixing enzymes; nitrate reductase (NR), glutamine synthetase (GS), and succinate dehydrogenase (SDH) showed chronological decrease by 93%, 90%, and 98%, respectively. Increased Bioremediation of pyrene by consortium JPNKA7B2 (Mix culture of Synechocystis sp., Pseudomonas indoxyladons, and Bacillus benzoevorans) was eliminated at 94.1% in 50 mg/L, which indirectly retarded the nitrogen fixing enzymes – NR, GS, and SDH. However, Synechocystis sp. monoculture could remediate up to 36% at 1.5 mg/L after 16 days of incubation.

Biodegradation of crude oil by a defined co-culture of indigenous bacterial consortium and exogenous Bacillus subtilis

The aim of this work was to study biodegradation of crude oil by defined co-cultures of indigenous bacterial consortium and exogenous Bacillus subtilis. Through residual oil analysis, it is apparent that the defined co-culture displayed a degradation ratio (85.01%) superior to indigenous bacterial consortium (71.32%) after 7days of incubation when ratio of inoculation size of indigenous bacterial consortium and Bacillus subtilis was 2:1. Long-chain n-alkanes could be degraded markedly by Bacillus subtilis. Result analysis of the bacterial community showed that a decrease in bacterial diversity in the defined co-culture and the enrichment of Burkholderiales order (98.1%) degrading hydrocarbons. The research results revealed that the promising potential of the defined co-culture for application to degradation of crude oil.

Extracellular Membrane Structures: A Component of the Epilithic Biofilm on the Kupferschiefer Black Shale

ABSTRACTThe presented study focuses on the characterization of extracellular membrane structures (EMSs) detected in the biofilm of an indigenous bacterial consortium growing on the surface of the Kupferschiefer black shale under model laboratory conditions. Received results showed that several types of extracellular structures, including multilayer vesicle-like structures observed for the first time, are a significant component of mixed-species bacterial biofilm. Based on the protein profile, the potential structure and functions of the EMSs were discussed. The findings of this study expand the current knowledge about biofilms formed by bacterial consortia on the surface of sedimentary rocks and show the diversity of EMSs produced by environmental microorganisms.

Simultaneous sequestration of ternary metal ions (Cr6+, Cu2+ and Zn2+) from aqueous solution by an indigenous bacterial consortium

Sequestration of single heavy metal contaminant from industrial wastewater using pure bacterial strains has received much attention. However, application of a bacterial consortium in multiple metals sequestration is scarce. The present study was aimed to develop a consortium from three bacterial strains for the simultaneous sequestration of ternary metal ions (Cr6+, Cu2+ and Zn2+) from aqueous solution. Kinetic studies showed that the individual strain, Pseudomonas taiwanensis; Acinetobacter guillouiae and Klebsiella pneumoniae were able to remove Cr6+, Cu2+ and Zn2+ respectively. These bacterial strains were utilized to develop an indigenous consortium based on metal removal affinities and positive interferences between them. Consortium showed improved performance over individual strains for the removal of single as well as simultaneous removal of three metal ions. Fourier transform infrared (FTIR) spectral analysis showed the possible involvement of carboxyl, amino, hydroxyl, methyl, phosphate and sulphonate groups in metal ions sequestration. Consortium exhibits greater adaptability in ternary metal ions mixture which indicates its robust growth mechanism over individual bacterial strains.

Microbial degradation of the brominated flame retardant TBNPA by groundwater bacteria: laboratory and field study

In the present study, the biodegradation of the brominated flame retardant tribromoneopentylalcohol (TBNPA) by a groundwater enrichment culture was investigated using a dual carbon (13C/12C)- bromine (81Br/79Br) stable isotope analysis. An indigenous aerobic bacterial consortium was enriched from the polluted groundwater underlying an industrial site in the northern Negev Desert, Israel, where TBNPA is an abundant pollutant. Aerobic biodegradation was shown to be rapid, with complete debromination within a few days, whereas anaerobic biodegradation was not observed. Biodegradation under aerobic conditions was accompanied by a significant carbon isotope effect with an isotopic enrichment factor of ɛCbulk = −8.8‰ ± 1.5‰, without any detectable bromine isotope fractionation. It was found that molecular oxygen is necessary for biodegradation to occur, suggesting an initial oxidative step. Based on these results, it was proposed that H abstraction from the C-H bond is the first step of TBNPA biodegradation under aerobic conditions, and that the C-H bond cleavage results in the formation of unstable intermediates, which are rapidly debrominated. A preliminary isotopic analysis of TBNPA in the groundwater underlying the industrial area revealed that there are no changes in the carbon and bromine isotope ratio values downstream of the contamination source. Considering that anoxic conditions prevail in the groundwater of the contaminated site, the lack of isotope shifts in TBNPA indicates the lack of TBNPA biodegradation in the groundwater, in accordance with our findings.

Effects of indigenous microbial consortia for enhanced oil recovery in a fragmented calcite rocks system

Two indigenous bacterial consortia, IMP-100 and IMP-200, proved to have a functional effect on heavy crude oil recovery, indicating a potential implementation in Microbial Enhanced Oil Recovery (MEOR). Growth kinetics of the indigenous bacterial population was performed under anaerobic conditions at 70 °C and 33 g L−1 of salinity. It was found that both extremophile consortia were able to grow under the latter conditions. Moreover, they synthesized metabolites that altered the surface properties of the supernatants derived from cell cultures, a useful property in oil recovery processes. Ex situ fermentations in the presence of crude oil-impregnated calcite rocks demonstrated that both bacterial consortia enhance crude oil recovery by 8.5% and 13%. In order to identify possible phenomena responsible for incremental oil recovery, emulsification index (E24), surface tension, cell adhesion to hydrocarbons, and crude oil viscosity were characterized. The results demonstrate that IMP-(100, 200) consortia were able to recover heavy crude oil from calcite rocks, possibly due to a decrease in crude oil viscosity, induced by the presence of metabolites and/or the interaction between bacteria and oil hydrocarbons.