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Sophorolipids are biobased compounds produced by the genera Starmerella and Pseudohyphozyma that gain exponential interest from academic and industrial stakeholders due to their mild and environmental friendly characteristics. Currently, industrially relevant sophorolipid volumetric productivities are reached up to 3.7 g center dot L-1 center dot h(-1) and sophorolipids are used in the personal care and cleaning industry at small scale. Moreover, applications in crop protection, food, biohydrometallurgy and medical fields are being extensively researched. The research and development of sophorolipids is at a crucial stage. Therefore, this work presents an overview of the state-of-the-art on sophorolipid research and their applications, while providing a critical assessment of scientific techniques and standardisation in reporting. In this review, the genuine sophorolipid producing organisms and the natural role of sophorolipids are discussed. Subsequently, an evaluation is made of innovations in production processes and the relevance of in-situ product recovery for process performance is discussed. Furthermore, a critical assessment of application research and its future perspectives are portrayed with a focus on the self-assembly of sophorolipid molecules. Following, genetic engineering strategies that affect the sophorolipid physiochemical properties are summarised. Finally, the impact of sophorolipids on the bioeconomy are uncovered, along with relevant future perspectives.

As we march into the 21st century, the prevailing scenario of depleting energy resources, global warming and ever increasing issues of human health and food security will quadruple. In this context, genetic and metabolic engineering of green microalgae complete the quest toward a continuum of environmentally clean fuel and food production. Evolutionarily related, but unlike land plants, microalgae need nominal land or water, and are best described as unicellular autotrophs using light energy to fix atmospheric carbon dioxide (CO2) into algal biomass, mitigating fossil CO2 pollution in the process. Remarkably, a feature innate to most microalgae is synthesis and accumulation of lipids (60-65% of dry weight), carbohydrates and secondary metabolites like pigments and vitamins, especially when grown under abiotic stress conditions. Particularly fruitful, such an application of abiotic stress factors such as nitrogen starvation, salinity, heat shock, etc., can be used in a biorefinery concept for production of multiple valuable products. The focus of this mini-review underlies metabolic reorientation practices and tolerance mechanisms as applied to green microalgae under specific stress stimuli for a sustainable pollution-free future. Moreover, we entail current progress on genetic engineering as a promising tool to grasp adaptive processes for improving strains with potential biotechnological interests.

BACKGROUND: Surface active compounds produced 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. RESULTS: Bioemulsifier production by a Paenibacillus sp. 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 40degreesC. It formed stable emulsions with several hydrocarbons and its emulsifying ability was not affected by exposure to high salinities (up to 300g/l), high temperatures (100degreesC-121degreesC) or a wide range of pH values (2-13). In addition, it presented low toxicity and high biodegradability when compared with chemical surfactants. 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. CONCLUSION: The production of a low molecular weight bioemulsifier by a novel Paenibacillus strain isolated from crude oil was reported. To the best of our knowledge, bioemulsifier production by Paenibacillus strains has not been previously reported. The features of this novel bioemulsifier make it an interesting biotechnological product for many environmental and industrial applications., This work was supported by PARTEX OIL AND GAS. The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013. Jorge F. B. Pereira acknowledges the financial support from Fundacao para a Ciencia e a Tecnologia through doctoral research grant SFRH/BD/60228/2009.

To create compatible interface for enzyme immobilization, the surface of multi-walled carbon nanotubes (MWCNTs) was functionalized using soft technique dielectric barrier discharge plasma (DBDP) for carboxylation and amination; followed by further amidation of carboxyl group with alkylamine. Successful functionalization and enzyme immobilization were structurally confirmed using spectroscopic analysis Fourier-Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS). The immobilization of Candida rugosa lipase (CRL) on functionalized MWCNTs was evidenced by clearly viewing with Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM) imaging. CRL showed more Freundlich equilibrium behavior upon immobilization on annealed and octadecylamidated MWCNTs, which suggested a multilayer adsorption; while upon physical adsorption on aminated and carboxylated MWCNTs, CRL, to more extent, demonstrated a Langmuir equilibrium property, producing an enzyme monolayer. It was proven that DBDP-mediated surface-functionalization could create compatible microenvironments for enzyme immobilization, resulted in improved specific activity and thermostability. The immobilized CRL on octadecylamidated MWCNTs displayed excellent reusability and operation stability, indicating its potential for industrial application. (C) 2014 Elsevier B.V. All rights reserved.

Background: Mixed microbial cultures, in which bacteria and fungi interact, have been proposed as an efficient way to deconstruct plant waste. The characterization of specific microbial consortia could be the starting point for novel biotechnological applications related to the efficient conversion of lignocellulose to cello-oligosaccharides, plastics and/or biofuels. Here, the diversity, composition and predicted functional profiles of novel bacterial-fungal consortia are reported, on the basis of replicated aerobic wheat straw enrichment cultures.Results: In order to set up biodegradative microcosms, microbial communities were retrieved from a forest soil and introduced into a mineral salt medium containing 1% of (un) treated wheat straw. Following each incubation step, sequential transfers were carried out using 1 to 1,000 dilutions. The microbial source next to three sequential batch cultures (transfers 1, 3 and 10) were analyzed by bacterial 16S rRNA gene and fungal ITS1 pyrosequencing. Faith's phylogenetic diversity values became progressively smaller from the inoculum to the sequential batch cultures. Moreover, increases in the relative abundances of Enterobacteriales, Pseudomonadales, Flavobacteriales and Sphingobacteriales were noted along the enrichment process. Operational taxonomic units affiliated with Acinetobacter johnsonii, Pseudomonas putida and Sphingobacterium faecium were abundant and the underlying strains were successfully isolated. Interestingly, Klebsiella variicola (OTU1062) was found to dominate in both consortia, whereas K. variicola-affiliated strains retrieved from untreated wheat straw consortia showed endoglucanase/xylanase activities. Among the fungal players with high biotechnological relevance, we recovered members of the genera Penicillium, Acremonium, Coniochaeta and Trichosporon. Remarkably, the presence of peroxidases, alpha-L-fucosidases, beta-xylosidases, beta-mannases and beta-glucosidases, involved in lignocellulose degradation, was indicated by predictive bacterial metagenome reconstruction. Reassuringly, tests for specific (hemi) cellulolytic enzymatic activities, performed on the consortial secretomes, confirmed the presence of such gene functions.Conclusion: In an in-depth characterization of two wheat straw degrading microbial consortia, we revealed the enrichment and selection of specific bacterial and fungal taxa that were presumably involved in (hemi) cellulose degradation. Interestingly, the microbial community composition was strongly influenced by the wheat straw pretreatment. Finally, the functional bacterial-metagenome prediction and the evaluation of enzymatic activities (at the consortial secretomes) revealed the presence and enrichment of proteins involved in the deconstruction of plant biomass.

Biosurfactant production by three Bacillus subtilis strains (#309, #311 and #573) isolated from Brazilian crude oils was optimized based on different carbon and nitrogen sources. The lowest surface tension values were obtained using sucrose containing media for the three isolates. Biosurfactants produced by each strain were characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR), and Matrix-assisted laser desorption ionizationtime of flight mass spectrometry (MALDI-TOF). The chemical characterization showed that the three isolates produced very similar mixtures, containing C13-, C14- and C15-surfactin, although in different proportions. The structure of surfactins produced by the three strains was shown to be in good agreement with their surface-activities. The interfacial-activities of the biosurfactants were characterized and compared with chemical surfactants. Furthermore, the application of biosurfactants and chemical surfactants in oil recovery was evaluated. The results obtained showed that biosurfactants have better interfacial-activity and oil recovery efficiency than common chemical surfactants, thus being more attractive to be applied in Microbial Enhanced Oil Recovery., This work was supported by PARTEX OIL AND GAS. Jorge F.B. Pereira acknowledges the financial support from Fundacao para a Ciencia e a Tecnologia through doctoral research grant SFRH/BD/60228/2009. Rui Vitorino acknowledges the financial support from QOPNA and RNEM by the Fundacao para a Ciencia e a Tecnologia.

[EN] Dielectric measurements of different standard solutions (nucleotides, nucleosides, lactic acid and myoglobin) were assayed simulating the concentrations of these substances in early postmortem meat. These assays were performed for considering the potential use of dielectric spectra for the quality control of meat. Good correlations among solutions of Adenosine Triphosphate (ATP), Inosine Monophosphate (IMP) and lactic acid with loss factor at punctual frequencies (0.5, 0.915 and 1 GHz) were found. The other assayed substances did not present a marked effect over the electromagnetic spectra. Good correlations of dielectric properties with IMP and lactic acid content of real pork meat samples were also found at 0.5 GHz. This work is presenting prospective data of dielectric spectra for certain key biochemical markers in order to consider its potential application as a non-destructive control sensor for the prediction of pork meat quality. (C) 2010 Elsevier Ltd. All rights reserved., Grant from Agroalimed (Conselleria de Agricultura, Pesca y Alimentacion, Valencia, Spain) and FPU grant to M.C. from Ministry of Science and Innovation (Madrid, Spain) are fully acknowledged. Work prepared within the Unidad Asociada IAD (UPV)-IATA (CSIC) framework.

Biocompatibility of medical grade polyurethane coated with polyaniline (PANi) and polyaniline-silver nanoparticle composite (PANi-AgNp) is reported here. These modified films showed 23 and 18% of 3T3 L1 cell death when compared to 41% with virgin polyurethane (PU) after 48. h of incubation, respectively. All the surfaces elucidated inflammatory response in the form of enhanced expressions of the proinflammatory cytokines genes, TNF-? and IL-6. But these values were less (by 20%) on modified films than on the bare PU. Attachment of Pseudomonas and Bacillus were markedly less on PANi-AgNp coated surface (by 90.6 and 50.5%, respectively) when compared to the uncoated PU. As the CFU counts decreases on the nanoparticle coated PU, the adsorbed carbohydrate as well as protein content on to the surface of polymer decreases accordingly, indicating less attachment. A 20% reduction in the thickness of biofilm was observed in PANi-AgNp coated PU surface. A very strong positive correlation is observed between the contact angles of the polymers and the various biological parameters (namely colony forming units, protein, carbohydrate, cell death and inflammatory response), indicating hydrophilic surfaces prevent bacterial biofilm as well as are compatible to cells when compared to hydrophobic surfaces. Coating PU with PANi and PANi. +. AgNp renders the surface conductive, suggesting potential application in electrochemical biosensors. In addition, these modifications make the surface more biocompatible than the original PU. � 2011 Elsevier B.V.

International audience; Compared to temperature, the development of pressure as a tool in the research field has emerged only recently (at the end of the XIXth century). Following several developments in Physics and Chemistry during the first half of the XXth century (in particular the synthesis of diamond in 1953-1954), high pressures were applied in Food Science, especially in Japan. The main objective was then to achieve the decontamination of foods while preserving their organoleptic properties. Now, a new step is engaged: the biological applications of high pressures, from food to pharmaceuticals and biomedical applications. This paper will focus on three main points: (i) a brief presentation of the pressure parameter and its characteristics, (ii) a description of the pressure effects on biological constituents from simple to more complex structures and (iii) a review of the different domains for which the application of high pressures is able to initiate potential developments in Biotechnologies.

Isolation and characterization of the surface active components from the crude biosurfactant produced by Streptococcus thermophilus A was studied. A fraction rich in glycolipids was obtained by the fractionation of crude biosurfactant using hydrophobic interaction chromatography. Molecular (by Fourier transform infrared spectroscopy) and elemental compositions (by X-ray photoelectron spectroscopy) were determined. Critical micelle concentration achieved was 20 g/l, allowing for a surface tension value of 36 mJ/m2. Moreover, this glycolipid rich fraction was found to be an anti-adhesive and antimicrobial agent against several bacterial and yeast strains isolated from explanted voice prostheses. Further purification steps should be carefully analyzed as each purification step will increase the costs and decreases the amounts of biosurfactants recovered., Fundação para a Ciência e a Tecnologia(FCT) CACTI (Spain) ; University of Groningen, The Netherlands.

Enzyme-catalyzed production of biodiesel is the object of extensive research due to the global shortage of fossil fuels and increased environmental concerns. Herein we report the preparation and main characteristics of a novel biocatalyst consisting of Cross-Linked Enzyme Aggregates (CLEAs) of Candida antarctica lipase B (CALB) which are covalently bound to magnetic nanoparticles, and tackle its use for the synthesis of biodiesel from non-edible vegetable and waste frying oils. For this purpose, insolubilized CALB was covalently cross-linked to magnetic nanoparticles of magnetite which the surface was functionalized with –NH2 groups. The resulting biocatalyst combines the relevant catalytic properties of CLEAs (as great stability and feasibility for their reutilization) and the magnetic character, and thus the final product (mCLEAs) are superparamagnetic particles of a robust catalyst which is more stable than the free enzyme, easily recoverable from the reaction medium and reusable for new catalytic cycles. We have studied the main properties of this biocatalyst and we have assessed its utility to catalyze transesterification reactions to obtain biodiesel from non-edible vegetable oils including unrefined soybean, jatropha and cameline, as well as waste frying oil. Using 1% mCLEAs (w/w of oil) conversions near 80% were routinely obtained at 30°C after 24 h of reaction, this value rising to 92% after 72 h. Moreover, the magnetic biocatalyst can be easily recovered from the reaction mixture and reused for at least ten consecutive cycles of 24 h without apparent loss of activity. The obtained results suggest that mCLEAs prepared from CALB can become a powerful biocatalyst for application at industrial scale with better performance than those currently available. This work was supported by grants from the University of the Basque Country (UPV/EHU, project GIU11/25 and scholarship for AC-I, http://www.ehu.es), the Spanish Ministry of Economy and Competitiveness (project CTQ2011-25052, http://www.mineco.es), the Basque Government (project SAIOTEK S-PE12UN041, http://www.euskadi.net), Ikerbasque, the Basque Foundation for Science (fellowship for CL, www.ikerbasque.net) and European Union (project Energreen, POCTEFA EFA217/11, http://www.poctefa.eu/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.