Isolation of microorganisms from oil samples for application in microbial enhanced oil recovery

Este resumo faz parte de: Book of abstracts of the Meeting of the Institute for Biotechnology and Bioengineering, 2, Braga, Portugal, 2010. A versão completa do livro de atas está disponível em: http://hdl.handle.net/1822/1096

Improved rhamnolipid biosurfactant production by Burkholderia thailandensis E264 using agro-industrial waste

Biosurfactants are amphiphilic surface-active compounds, produced by various microorganisms, that reduce surface and interfacial tension. These compounds are attracting increasing interest over their chemical counterparts due to their advantages, such as biodegradability, high stability in extreme environments, low toxicity, low critical micelle concentrations (CMC) and the fact that they can be effectively produced from agro-industrial wastes and renewable resources. Furthermore, their diversity allows for a significant number of uses, including microbial enhanced oil recovery (MEOR), bioremediation and biomedical applications. However, the high operational costs, mainly regarding the use of expensive raw materials in the fermentation and the complex downstream processing, to yield low amounts of product restricts their industrial-scale applications. Several attempts to solve these limitations by reducing the production costs have been conducted and include the use of low-cost agro-industrial wastes and by-products as substrates. One of these low-cost substrates, that has been successfully used to produce biosurfactants by Bacillus subtilis and Pseudomonas aeruginosa strains, is Corn Steep Liquor (CSL). In this research, rhamnolipid biosurfactant production by Burkholderia thailandensis E264 was optimized using this agro-industrial waste as sole substrate. When grown in a culture medium containing CSL (7.5% v/v), this strain produced 1.77 g biosurfactant/L, which is about 2.6 times the amount of biosurfactant produced in the standard synthetic medium. The purified biosurfactant produced in the low-cost medium exhibited similar surface-active properties when compared with that produced in the synthetic medium, reducing the surface tension of water to 29.7 mN/m, with a CMC of 385 mg/L. HPLC analysis showed that the culture medium used contains about 2.6 g/L of fructose and 2.5 g/L of glucose, that are fully consumed within the first 48 h of fermentation. Since the synthetic medium contains 40 g/L of glycerol, results suggest that biosurfactant production is more efficient in the low-cost medium. Furthermore, to the best of the authors knowledge, this is the first experimental research that combines the utilization of B. thailandensis with CSL to produce biosurfactants with very optimistic results in terms of cost and production levels. The rhamnolipid-containing cell-free supernatant could be used directly in bioremediation or MEOR processes.This study was supported by PARTEX Oil and Gas, and the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund (ERDF) under the scope of Norte 2020 - Programa Operacional Regional do Norte. The authors also acknowledge to the Biomass and Bioenergy Research Infrastructure (BBRI)- LISBOA-01-0145-FEDER-022059, supported by Operational Program for Competitiveness and Internationalization (PORTUGAL2020), by Lisbon Portugal Regional Operational Program (Lisboa 2020) and by North Portugal Regional Operational Program (Norte 2020) under the Portugal 2020 Partnership Agreement, through the ERDF.info:eu-repo/semantics/publishedVersio

Biosurfactant-producing Bacillus subtilis strains isolated from crude oil samples enhance oil recovery at lab scale

Biosurfactant-producing Bacillus subtilis strains isolated from crude oil samples enhance oil recovery at lab scale Eduardo J Gudiña, Lígia R. Rodrigues, José A. Teixeira IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal Microbial Enhanced Oil Recovery (MEOR) is potentially useful to increment oil recovery from reservoirs beyond primary and secondary recovery operations using microorganisms and their metabolites. Stimulation of bacterial growth and biosurfactant production by indigenous microorganisms can reduce the capillary forces that retain the oil into the reservoir. MEOR offers major advantages over conventional EOR, namely low amounts of energy consumption and independence of the price of crude oil [1]. In this work, a sand pack column model was designed to simulate the oil recovery operations in oil reservoirs and evaluate the mobilization of residual oil. Three Bacillus subtilis strains, previously isolated from crude oil samples [2], were used. Those strains grow and produce extracellular biosurfactants at 40ºC under anaerobic conditions in medium supplemented with hydrocarbons. Biosurfactants produced reduce the surface tension of water from 72 to 30 mN/m, exhibit emulsifying activity and are not affected by exposure to high temperatures (121ºC) which makes them good candidates for application in biosurfactant mediated MEOR. Sand pack column assays were performed using paraffin and crude oil. Additional oil recovery using paraffin ranged from 19 to 35% with the different isolates. When crude oil was used as hydrocarbon, the isolates recovered between 19 and 21% of the entrapped oil. The results obtained suggest that stimulation of biosurfactant production by these strains in situ can contribute to mobilize entrapped oil and improve the oil fluidity. [1] Sen R, “Biotechnology in petroleum recovery: The microbial EOR”, Progress in Energy and Combustion Science (2008) 34: 714-724. [2] Gudiña EJ, Pereira JFB, Rodrigues LR, Coutinho JAP, Teixeira JA, “Isolation and study of microorganisms from oil samples for application in Microbial Enhanced Oil Recovery”, International Biodeterioration and Biodegradation (2012) 68: 56-64

Biosurfactant-producing lactobacilli : screening, production profiles and effect of medium composition

Biosurfactant production was screened in four lactobacilli strains. The highest biosurfactant production (excreted and cellbound biosurfactants) was achieved with Lactobacillus paracasei ssp. paracasei A20, a strain isolated from a Portuguese dairy plant, with a decrease in the surface tension of 6.4mNm−1 and 22.0mNm−1, respectively. Biosurfactant production by this strain was evaluated under different culture broth compositions. The use of different nitrogen sources revealed that yeast extract is essential for bacterial growth, while peptone is crucial for biosurfactant synthesis. For biosurfactant production, the use of peptone and meat extract yielded a higher production when compared to the standard medium, with a surface tension reduction of 24.5mNm−1. Furthermore, experiments were also conducted in a reactor with pH and temperature control. Biomass and biosurfactant production in bioreactor was higher comparing with the experiments conducted in shake flaks. The optimization procedure adopted in the current work was found to improve the biosurfactant production and opened new perspectives for the use of L. paracasei ssp. paracasei A20 as a promising biosurfactant-producer

Novel bioemulsifier produced by a Paenibacilus sp. strain and its applicability in microbial enhanced oil recovery

Microbial Enhanced Oil Recovery (MEOR) is potentially useful to increment oil recovery from reservoirs beyond primary and secondary recovery operations using microorganisms and their metabolites. In situ stimulation of microorganisms that produce surface active compounds reduces the capillary forces that retain the oil inside the reservoir, thus promoting its flow and increasing oil production. Paenibacillus sp. #510, isolated from crude oil samples obtained from a Brazilian oil field, produced a bioemulsifier in a mineral medium containing sucrose as the carbon source under aerobic and anaerobic conditions, and its production was induced (up to 7.9 g/l) by the addition of paraffin or crude oil to the culture medium. It formed stable emulsions with several hydrocarbons and its emulsifying ability was not affected by exposure to high salinities (up to 300 g/l), high temperatures (100ºC-121ºC) or a wide range of pH values (2-13). This is the first description of bioemulsifier production by a Paenibacillus strain. A preliminary chemical characterization by Fourier Transform Infrared Spectroscopy (FT-IR), proton and carbon nuclear magnetic resonance (1H NMR and 13C CP-MAS NMR) and size exclusion chromatography indicated that this new bioemulsifier is a low-molecular weight oligosaccharide-lipid complex. Mobilization of heavy crude oil by this isolate was evaluated using a core-flooding equipment working at the oil reservoir pressure (32.4 bar) and temperature (40ºC). Growing in situ Paenibacillus sp. #510 for 14 days at the oil reservoir conditions using a mineral medium resulted in the mobilization of 6% of the entrapped heavy oil, confirming that this isolate can contribute to enhance oil recovery from mature reservoirs. These results will be further validated in a pilot field assay

Potential therapeutic applications of biosurfactants

Biosurfactants have recently emerged as promising molecules for their structural novelty, versatility, and diverse properties that are potentially useful for many therapeutic applications. Mainly due to their surface activity, these molecules interact with cell membranes of several organisms and/or with the surrounding environments, and thus can be viewed as potential cancer therapeutics or as constituents of drug delivery systems. Some types of microbial surfactants, such as lipopeptides and glycolipids, have been shown to selectively inhibit the proliferation of cancer cells and to disrupt cell membranes causing their lysis through apoptosis pathways. Moreover, biosurfactants as drug delivery vehicles offer commercially attractive and scientifically novel applications. This review covers the current state-ofthe- art in biosurfactant research for therapeutic purposes, providing new directions towards the discovery and development of molecules with novel structures and diverse functions for advanced applications.The authors acknowledge Fundacao para a Ciencia e a Tecnologia (FCT) (Portugal) and the Department of Science and Technology (DST) (India) for financial support of the project 'MEDSURF - The potential use of biosurfactants for medical applications' developed under the scope of a bilateral agreement between Portugal and India

New microbial surface-active compounds: the ultimate alternative to chemical surfactants?

Surface active compounds (SACs) produced by microorganisms are attracting a pronounced interest due to their potential advantages over synthetic counterparts, and to the fact that they could replace some of the synthetics in many environmental and industrial applications. Bioemulsifier production by a Paenibacillus strain isolated from crude oil was studied. The bioemulsifier was produced using sucrose with and without adding hydrocarbons (paraffin or crude oil) under aerobic and anaerobic conditions at 40ºC. It formed stable emulsions with several hydrocarbons, exhibiting similar or better emulsifying activity when compared with chemical SACs, and its emulsifying ability was not affected by exposure to high salinities (up to 300 g/l), high temperatures (100-121ºC) or a wide range of pH values (2-13). In addition, it presented low toxicity and high biodegradability when compared with chemical surfactants, implying a greater environmental compatibility. A preliminary chemical characterization by Fourier Transform Infrared Spectroscopy (FT-IR), proton and carbon nuclear magnetic resonance (1H NMR and 13C CP-MAS NMR) and size exclusion chromatography indicated that the bioemulsifier is a low molecular weight oligosaccharide-lipid complex. To the best of our knowledge, bioemulsifier production by a Paenibacillus strain has not been previously reported. This is also the first description of a low molecular weight bioemulsifier. The features of this novel bioemulsifier make it an interesting biotechnological product for many environmental and industrial applications.Financial support from the projects BIOCLEAN-Desenvolvimento de produtos contendo surfactantes microbianos para limpeza e desinfeção de superfícies industriais e domésticas. QREN-n.º 2013/030215, and NCMICROBIOS -Desenvolvimento de bioprocessos usando microrganismos não convencionais para a produção de biosurfactantes - Convénio FCT-CNPq Nº 17/2013 – Ref.: Projecto nº 6818

Biosurfactants: production, applications and future potential

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Surfactants are one of the most important classes of industrial chemicals in terms of production volume. These compounds exhibit a wide variety of applications in several industries and are present in nearly every product and aspect of our daily life. They can be found in detergents, laundry formulations, household cleaning products, cosmetics, herbicides or pesticides, and are also used in bioremediation, agriculture, food, pharmaceutical, textile, paper or the petroleum industries, among others. Most conventional surfactants available nowadays are derived from non-renewable resources and their use may lead to significant ecological problems due to their toxicity and low biodegradability. In the recent years, an increase in environmental awareness has led to much more interest in the use of renewablebased, biodegradable and more environmentally friendly surfactants. Among them biosurfactants, surface-active compounds synthesized by microorganisms, are attracting a pronounced interest due to their potential advantages over their synthetic counterparts, and to the fact that they could replace some of the synthetics in many environmental and industrial applications. [...]info:eu-repo/semantics/publishedVersio

Development of low-cost culture media for effective biosurfactant production

In this work, biosurfactant production by Pseudomonas aeruginosa and Bacillus subtillis strains was optimized using low-cost substrates. The highest biosurfactant production (3.2 g/L) by the P. aeruginosa strain was obtained using a culture medium containing corn steep liquor (CSL) (10% (v/v)) and molasses (10% (w/v)), whereas the best biosurfactant production by the B. subtillis isolate (1.3 g/L) was obtained using a culture medium consisting of 10% (v/v) of CSL. Subsequently, for the B. subtillis strain, the effect of different metals (iron, manganese and magnesium) on biosurfactant production was evaluated. When the culture medium CSL 10% was supplemented with the optimum concentration of those metals simultaneously, the biosurfactant production was increased up to 4.8 g/L. The biosurfactant produced by the P. aeruginosa strain was characterized as a mixture of eight different rhamnolipid congeners, being the most abundant the mono-rhamnolipid Rha-C10-C10, and the biosurfactant produced by the B. subtillis isolate consisted of a mixture of C13-, C14- and C15-surfactin. Both biosurfactants exhibited a good performance in oil recovery assays when compared with chemical surfactants, suggesting their potential use as an alternative to traditional chemical surfactants in enhanced oil recovery or bioremediation