Cassava wastewater as a substrate for the simultaneous production of rhamnolipids and polyhydroxyalkanoates by Pseudomonas aeruginosa

Glycerol, cassava wastewater (CW), waste cooking oil and CW with waste frying oils were evaluated as alternative low-cost carbon substrates for the production of rhamnolipids and polyhydroxyalkanoates (PHAs) by various Pseudomonas aeruginosa strains. The polymers and surfactants produced were characterized by gas chromatography-mass spectrophotometry (MS) and by high-performance liquid chromatography-MS, and their composition was found to vary with the carbon source and the strain used in the fermentation. The best overall production of rhamnolipids and PHAs was obtained with CW with frying oil as the carbon source, with PHA production corresponding to 39% of the cell dry weight and rhamnolipid production being 660 mg l(-1). Under these conditions, the surface tension of the culture decreased to 30 mN m(-1), and the critical micelle concentration was 26.5 mg l(-1). It would appear that CW with frying oil has the highest potential as an alternative substrate, and its use may contribute to a reduction in the overall environmental impact generated by discarding such residues.

Pseudomonas aeruginosa LBI production as an integrated process using the wastes from sunflower-oil refining as a substrate

Pseudomonas aeruginosa LBI produced surface active rhamnolipids when cultivated on waste from the sunflower-oil process under different conditions. These biosurfactants, which reduce the superficial and interfacial tensions between fluids, offer advantages over their chemical counterparts, especially because of their ecological acceptability. These molecules can be used in fields as diverse as chemical, pharmaceutical and petrochemical industries. In this work, we present the effect of C/N ratio on growth and production yield. The best production yields (Y-P/S) were achieved for C/N ratios (in g/g) of 8/1 (0.22) and 6.4/1 (0.23). The product concentration was very satisfactory (7.3 g/L) at C/N ratio of 8/1, especially when considering that the substrate was basically composed of wastes that would otherwise constitute an environmental disposal problem. (c) 2007 Elsevier Ltd. All rights reserved.

Structure, properties and applications of rhamnolipids produced by Pseudomonas aeruginosa L2-1 from cassava wastewater

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of C/N Ratio and Physicochemical Conditions on the production of Rhamnolipids by Pseudomonas Aeruginosa LBI

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Wettability of Aqueous Rhamnolipids Solutions Produced by Pseudomonas aeruginosa LBI

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cassava wastewater as a substrate for the simultaneous production of rhamnolipids and polyhydroxyalkanoates by Pseudomonas aeruginosa

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Factors affecting rhamnolipids production by Pseudomonas aeruginosa LBI

This paper presents the results from study investigating the capacity of Pseudomonas aeruginosa LBI growing on several carbon (Hydrophilic substrate) and nitrogen sources. The carbon source (2016) studied were: glycerol, manitol, fructose, glucose, lactose and the nitrogen sources (2; 3; 4 and 5016) were: NaNO3, NH4NO3, (NH4)(2)SO4 and (NH2)(2)CO. At the 96 h of fermentation, the medium with glycerol as a carbon source reached 7.9 g/L of rhamnolipids and 1. 2 g/L cellular protein. The surface tension reduction was 38.46 % for glycerol as a carbon source. The NaNO3 at 3% was the best concentration for rhamnolipids production (7.35 g/L) and cellular protein (1.12 g/L). The influences of metal ions [FeSO4.7H(2)O (0.001g/L, 0.005 g/L and 0.1 g/L) and MgSO4.7H(2)O (0.001 g/L, 0.005 g/L and 0.1 g/L)] on ramnolipids production were studied. Fe2+ had a negative influence on the studied concentrations while Mg2+ had a positive influence when its concentration was increased.

Produção de biotensoativos a partir de resíduos de óleos e gorduras

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Production of Pseudomonas aeruginosa LBI rhamnolipids following growth on Brazilian native oils

Oils from Buriti (Mauritia flexuosa), Cupuacu (Theobroma grandiflora), Passion Fruit (Passiflora alata), Andiroba (Carapa gitianensis), Brazilian Nut (Bertholletia excelsa) and Babassu (Orbignya spp.) were evaluated as carbon sources for rhamnolipid production by Pseudomonas aeruginosa LBI. The highest rhamnolipid concentrations were obtained from Brazilian Nut (9.9 l(-1)) and Passion Fruit (9.2 g l(-1)) oils. Surface tension varied from 29.8 to 31.5 mN m(-1), critical micelle concentration from 55 to 163 mg l(-1) and the emulsifying activity was higher against toluene (93-100%) than against kerosene (70-92%). Preliminary characterization of the surfactant mixtures by mass spectrometry revealed the presence of two major components showing m/z of 649 and 503, which corresponded to the dirhamnolipid (Rha(2)C(10)C(10)) and the monorhamnolipid (RhaC(10)C(10)), respectively. The monorhamnolipid detected as the ion of m/z 503 is predominant in all samples analyzed. (c) 2005 Elsevier Ltd. All rights reserved.

Chemical structure, surface properties and biological activities of the biosurfactant produced by Pseudomonas aeruginosa LBI from soapstock

Pseudomonas aeruginosa LBI isolated from petroleum-contaminated soil produced rhamnolipids (RLLBI) when cultivated on soapstock as the sole carbon source. HPLC-MS analysis of the purified culture supernatant identified 6 RL homologues (%): R-2 C-10 C-10 28.9; R-2 C-10 C-12:1 23.0; R-1 C-10 C-10 23.4; R-2 C-10 C-12 11.3; R-2 C-10 C-12 7.9; R-2 C-10 C-12 C-12 5.5. To assess the potential antimicrobial activity of the new rhamnolipid product, RLLBI, its physicochemical properties were studied. RLLBI had a surface tension of 24 mN m(-1) and an interfacial tension 1.31 mN m(-1); the cmc was 120 mg l(-1). RLLBI produced stable emulsions with hydrocarbons and vegetable oils. This product showed good antimicrobial behaviour against bacteria: MIC for Bacillus subtilis, Staphylococcus aureus and Proteus vulgaris was 8 mg l(-1), for Streptococcus faecalis 4 mg l(-1), and for Pseudomonas aeruginosa 32 mg l(-1). RLLBI was active against phytopathogenic fungal species, MIC values of 32 mg l(-1) being found against Penicillium, Alternaria, Gliocadium virens and Chaetonium globosum. Due to its physicochemical properties and antimicrobial behaviour, RLLBI could be used in bioremediation treatment and in the food, cosmetic and pharmaceutical industries.

Investigação dos efeitos tóxicos do biossurfactante ramnolipídio e suas implicações quando usado na biorremediação de águas contaminadas por petróleo

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Estudo da produção de metabólitos por Pseudomonas aeruginosa: Ramnolipídios e Polihidroxialcanoatos (PHAs)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenvolvimento de estratégias de alimentação para produção de ramnolipídios por Pseudomonas aeruginosa LBI 2A1 em biorreator

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biorremediação de solo contaminado com óleo lubrificante pela aplicação de diferentes soluções de surfactante químico e biossurfactante produzido por Pseudomonas aeruginosa LBI

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)