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Microbial exopolysaccharides (EPS) are promising alternatives to synthetic polymers in a variety of applications. Their high production costs, however, limit their use despite their outstanding properties. The use of low-cost substrates such as agro-industrial wastes in their production, can help to boost their market competitiveness. In this work, an alternative low-cost culture medium (CSLM) was developed for EPS production by

Polymer flooding is one of the most promising techniques used to increase the productivity of mature oil reservoirs. Polymers reduce the mobility ratio of the injected water relative to the crude oil, improving the displacement of the entrapped oil and consequently, increasing oil recovery. Biopolymers such as xanthan gum have emerged as environmentally friendly alternatives to the chemical polymers commonly employed by the oil industry. However, in order to seek more efficient biomolecules, alternative biopolymers must be studied. Here, the applicability of a biopolymer produced by Rhizobium viscosum CECT 908 in Microbial Enhanced Oil Recovery (MEOR) was evaluated. This biopolymer exhibited better rheological properties (including higher viscosity) when compared with xanthan gum. Its stability at high shear rates (up to 300 s-1), temperatures (up to 80?°C) and salinities (up to 200?g/L of NaCl) was also demonstrated. The biopolymer exhibited better performance than xanthan gum in oil recovery assays performed with a heavy crude oil, achieving 25.7?±?0.5% of additional recovery. Thus the R. viscosum CECT 908 biopolymer is a promising candidate for application in MEOR., This work was supported by PARTEX OIL AND GAS (Lisobon, Portugal). The authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for financial support under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684). The authors also acknowledge financial support from BioTecNorte operation (NORTE-01-0145FEDER-000004) and the project MultiBiorefinery (POCI-01-0145FEDER-016403) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Márcia R. Couto was supported by the doctoral Grant SFRH/BD/ 132998/2017 provided by FCT. Débora Ferreira is recipient of a fellowship (UMINHO/BD/21/2016) supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.E.J.Gudiñawassupported bythePost-Doctoral grant UMINHO/BPD/39/2015 from the project UID/BIO/04469/2013, funded by FCT., info:eu-repo/semantics/publishedVersion

Supplementary data associated with this article can be found, inthe online version, at http://dx.doi.org/10.1016/j.bej.2017.05.015., Hydroxycinnamic acids and curcumin are compounds with great therapeutic potential, including anticancer properties. In this study, p-coumaric acid, caffeic acid and curcumin were produced in Escherichia coli. Their production was induced by heat using the dnaK and ibpA heat shock promoters. The ribosome binding site (RBS) used was tested and further optimized for each gene to assure an efficient translation. p-Coumaric acid was successfully produced from tyrosine and caffeic acid was produced either from tyrosine or p-coumaric acid using tyrosine ammonia lyase (TAL) from Rhodotorula glutinis, 4-coumarate 3-hydroxylase (C3H) from Saccharothrix espanaensis or cytochrome P450 CYP199A2 from Rhodopseudomonas palustris. The highest p-coumaric acid production obtained was 2.5 mM; caffeic acid production reached 370 M. Regarding curcumin, 17 M was produced using 4-coumarate-CoA ligase (4CL1) from Arabidopsis thaliana, diketide-CoA synthase (DCS) and curcumin synthase 1 (CURS1) from Curcuma longa. Stronger RBSs and/or different induction conditions should be further evaluated to optimize those production levels. Herein it was demonstrated that the biosynthetic pathway of p-coumaric acid, caffeic acid and curcumin in E. coli can be triggered by using heat shock promoters, suggesting its potential for the development of new industrial bioprocesses or even new bacterial therapies., FundingThis study was supported by the Portuguese Foundationfor Science and Technology (FCT) under the scope of thestrategic funding of UID/BIO/04469/2013 unit and COMPETE2020 (POCI-01-0145-FEDER-006684) and under the scope ofthe Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462). The authors also acknowledge financial support fromBioTecNorte operation (NORTE-01-0145-FEDER-000004) and theproject MultiBiorefinery (POCI-01-0145-FEDER-016403) funded by the European Regional Development Fund under the scope ofNorte2020 − Programa Operacional Regional do Norte and the Post-doctoral grant (UMINHO/BPD/37/2015) to J. L. Rodrigues funded byFCT., info:eu-repo/semantics/publishedVersion

Curcumin is a plant secondary metabolite with outstanding therapeutic effects. Therefore, there is a great interest in developing new strategies to produce this high-value compound in a cheaper and environmentally friendly way. Curcumin heterologous production in E. coli using artificial biosynthetic pathways was previously demonstrated using synthetic biology approaches. However, the culturing conditions to produce this compound were not optimized and so far only a two-step fermentation involving the exchange of the culture medium allowed to obtain high concentrations of curcumin, which limits its production at an industrial scale. In this study, the culturing conditions to produce curcumin were evaluated and optimized. In addition, it was concluded that E. coli BL21 allows to produce higher concentrations compared to E. coli K-12 strains. Different IPTG concentrations, time of protein expression induction and substrate type and concentration were also evaluated. The highest curcumin production obtained was 959.3 µM (95.93% of percent yield), which was 3.1-fold higher than the highest concentration previously reported. This concentration was obtained using a two-stage fermentation with LB and M9. Moreover, TB demonstrated to be a very interesting alternative medium to produce curcumin since it also led to high concentrations (817.7 µM). The use of this single fermentation medium represents an advantage at industrial scale and although the final production is lower than the one obtained with the LB-M9 combination, it leads to a significantly higher curcumin production in the first 24 h of fermentation. This study allowed obtaining the highest concentrations of curcumin reported so far in a heterologous organism and is of interest for all of those working with the heterologous production of curcuminoids, other complex polyphenolic compounds or plant secondary metabolites., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of the UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01- 0145-FEDER-006684) and under the scope of the Project MultiBiorefinery-Multi-purpose strategies for broadband agro-forest and fisheries by-products valorization: a step forward for a truly integrated biorefinery (POCI-01-0145-FEDER-016403). The authors also acknowledge financial support from BioTecNorte operation (NORTE-01-0145-FEDER-000004), funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte and the post-doctoral grant (UMINHO/BPD/37/2015) to J.L.R. funded by FCT., info:eu-repo/semantics/publishedVersion

Polymer-flooding is one of the most promising techniques used to increase the productivity of mature oil reservoirs. Polymers reduce the mobility ratio of the injected water relative to the crude oil, improving the displacement of the entrapped oil and, consequently, increasing oil recovery. Biopolymers such as xanthan gum have emerged as eco-friendly alternatives to the chemical polymers commonly used by the oil industry. However, in order to seek for more efficient biomolecules, alternative biopolymers must be studied. In the present work, the biopolymer produced by Arthrobacter viscosus CECT 908 was studied for the first time for a possible application in Microbial Enhanced Oil Recovery (MEOR). The rheological properties of this biopolymer were studied and compared with those of xanthan gum. The results demonstrated that the biopolymer produced by A. viscosus CECT 908 exhibited higher viscosity values (1207 ± 14 mPa.s at a concentration of 2.5 g/L, 40°C and a shear rate of 1.4 s1) when compared with xanthan gum at the same conditions (281 ± 11 mPa.s). The structure of the biopolymer was not affected by high shear rates (up to 300 s1), which is important for its application in enhanced oil recovery processes. Furthermore, it remained stable after exposure at high temperatures (up to 80°C) and salinities (up to 200 g NaCl/L), making it useful for application in a wide range of oil reservoirs. In sand-pack column assays performed using a heavy crude oil (40°C= 167 mPa.s) this biopolymer allowed a higher additional oil recovery (25.7 ± 0.5%) when compared with xanthan gum (19.8 ± 1.2%) due to the achievement of a more favorable mobility ratio between the injected biopolymer solution and the crude oil, which resulted in a more uniform displacement front. The results herein obtained demonstrated, for the first time, that the biopolymer produced by A. viscosus CECT 908 is a promising agent for enhancing heavy oil recovery in high temperature and high salinity oil reservoirs. Copyright 2018, Society of Petroleum Engineers., This work was supported by PARTEX OIL AND GAS. The authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for the financial support under the scope of the strategic funding of UID/ BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684), and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The authors also thank the FCT for the financial support under the scope of the Project MultiBiorefinery - Multi-purpose strategies for broadband agro-forest and fisheries by-products valorisation: a step forward for a truly integrated biorefmery (POCI-01-0145- FEDER-016403). E. I Guditia was supported by the Post-Doctoral grant CEB-BPD/01/2015/07 from the project MD/BIG/0446912013, funded by FCT., info:eu-repo/semantics/publishedVersion