From industrial wastewater to high performance bioplastics: knowledge integration for efficient decision-making

The potential processes for the production of bioplastics from industrial wastewater are characterised by the combination of technologies of uneven maturity. This contribution deals with integration of knowledge of different sources, namely: mathematical models, literature data processed in a meta analysis and experimental data from the most novel technologies. From this knowledge integration, the evaluation of the environmental performance of the whole value chain is performed by life cycle assessment. Carrying out this evaluation in an early-stage of development is intended to help decision-making in the optimisation and selection of technologies and target efforts in the improvement of sustainability hot-spots

Knowledge integration for efficient decicion-making: a case study from fish-canning wastewater valorization

The recovery of resources from food industries wastewater and further transformation into high performance biodegradable plastics is an ambitious objective which fulfils the objectives of circular economy and SDGs 6 and 14: i) a potentially harmful water pollutant if discharged is converted instead into an added-value product; ii) ensuring biodegradability in marine conditions, the plastic pollution is greatly minimised. In the framework of H2020 project USABLE-PACKAGING (www.usable-packaging.eu), we are carrying out a comprehensive analysis of a selection of representative value chains, from the industrial effluent to the final bioplastic product and potential by-products to ensure its economic and environmental sustainability. In particular, we are integrating knowledge from different sources, namely from deliberately designed experiments, mathematical models and literature reviews, for the holistic assessment of the environmental performance of several scenarios, with different wastewater characteristics (i.e. substrate) and a diverse range of bioplastic applications (i.e. final product)

Valorization of horse chestnut burs to produce simultaneously valuable compounds under a green integrated biorefinery approach

11 pages, 5 figures, 6 tablesA biorefinery scheme for the valorization of horse chestnut biowastes (a municipal solid waste) into added value bioactive compounds is proposed in this work. The bur fraction of horse chestnut was evaluated as a novel and cheap renewable feedstock to obtain valuable compounds suitable for their use in industrial applications. The integrated valorization scheme comprised an initial hydroethanolic extraction of antioxidant compounds (optimized through surface response methodology), the alkaline delignification of the exhausted solid to obtain a lignin-enriched fraction, and the enzymatic digestibility of the remaining cellulose fraction to produce fermentable sugars. In addition, the structural characterization of the extract by FT-IR and TGA was performed, and the analysis by UPLC-DAD-ESI-MS allowed the tentative identification of eleven antioxidant phenolic compounds. The application of this multiproduct valorization approach led to the production of 13 kg antioxidant extracted compounds, 33.2 kg lignin and 14.5 kg glucose per each 100 kg of horse chestnut burs, which demonstrates the great potential of this residue as a biorefinery substrateThis work was funded by the Ministry of Science, Innovation and Universities (RTI2018-094482-J-I00). G.E., A.M.-M. and T.A.L-C. belong to the Galician Competitive Research Group GRC-ED431C 2017/29 and the CRETUS Strategic Partnership (ED431E 2018/01). These programs are co-funded by FEDER (EU). Beatriz Gullón and Gemma Eibes would like to express their gratitude to the Ministry of Science, Innovation and Universities for financial support (Grant reference RYC2018-026177-I and RYC2018-024846-I). Abel Muñiz-Mouro thanks the Programa de axudas á etapa predoutoral da Xunta de GaliciaPeer reviewe

A new strain of Bjerkandera sp. production, purification and characterization of versatile peroxidase

8 páginas, 4 figuras, 2 tablas -- PAGS nros. 115-122The lignin modifying enzymes (LMEs) secreted by a new white rot fungus isolated from Chile were studied in this work. This fungus has been identified as a new anamorph of Bjerkandera sp. based on the sequences of the ribosomal DNA and morphological analysis at light microscopy showing hyaline hyphae without clamp connection, cylindrical conidia and lack of sexual forms, similar to those reported in other Bjerkandera anamorphs. The characterization of the culture medium for the highest LMEs production was performed in flask cultures, with a formulation of the culture medium containing high levels of glucose and peptone. The highest Mn-oxidizing peroxidase activity (1,400 U/L) was achieved on day 6 in Erlenmeyer flasks. Four peroxidases (named R1B1, R1B2, R1B3 and R1B4), have been purified by using ion-exchange and exclusion molar chromatographies. All of them showed typical activity on Mn2+ and exhibited Mn-independent activity against 2,6-dimethoxyphenol. R1B4 showed also activity on veratryl alcohol (pH 3) indicating that this enzyme belongs to the versatile peroxidase family. The high VP production capacities of this strain, as well as the enzymatic characteristics of the LMEs suggest that it may be successfully used in the degradation of recalcitrant compoundsThis study has been supported by the Spanish projects S-0505/AMB0100, PGIDIT06PXIB265088PR and CTQ2007-66788, and the European project EUI2008-03703. Authors thanks M. Jurado and B. Casas by your help in ITS analysis and electrophoretic techniques. R. Taboada thanks to BES-2008-006977 PhD fellowship. T. Lu-Chau wishes to thank the Isabel Barreto program from the Galician Government for the economical support provided during the development of this workPeer reviewe

Laccase Activity as an Essential Factor in the Oligomerization of Rutin

The enzyme-mediated polymerization of bioactive phenolic compounds, such as the flavonoid rutin, has gained interest due to the enhanced physico-chemical and biological properties of the products, which increases their potential application as a nutraceutical. In this work, the influence of enzyme activity on rutin oligomerization was evaluated in reactions with low (1000 U/L) and high (10,000 U/L) initial laccase activities. For both reactions, high molecular weight oligomer fractions showed better properties compared to lower weight oligomers. Products of the reaction with low laccase activity exhibited thermal stability and antioxidant potential similar to control reaction, but led to higher inhibitory activity of xanthine oxidase and apparent aqueous solubility. Oligomers obtained in the reaction with high laccase activity showed better apparent aqueous solubility but decreased biological activities and stability. Their low antioxidant activity was correlated with a decreased phenolic content, which could be attributed to the formation of several bonds between rutin molecules

Effect of culture temperature on the heterologous expression of Pleurotus eryngii versatile peroxidase in Aspergillus hosts

6 páginas, 4 figuras, 1 tabla -- PAGS nros. 129-134Production of recombinant versatile peroxidase in Aspergillus hosts was optimized through the modification of temperature during bioreactor cultivations. To further this purpose, the cDNA encoding a versatile peroxidase of Pleurotus eryngii was expressed under control of the alcohol dehydrogenase (alcA) promoter of Aspergillus nidulans. A dependence of recombinant peroxidase production on cultivation temperature was found. Lowering the culture temperature from 28 to 19 °C enhanced the level of active peroxidase 5.8-fold and reduced the effective proteolytic activity twofold. Thus, a maximum peroxidase activity of 466 U L-1 was reached. The same optimization scheme was applied to a recombinant Aspergillus niger that bore the alcohol dehydrogenase regulator (alcR), enabling transformation with the peroxidase cDNA under the same alcA promoter. However, with this strain, the peroxidase activity was not improved, while the effective proteolytic activity was increased between 3- and 11-fold compared to that obtained with A. nidulansThis work was partially supported by the EU contract “Fungal metalloenzymes oxidizing aromatic compounds of industrial interest” (QLK3-99-590), the Comunidad de Madrid, and the Spanish Commission of Science and Technology (BIO98-610 and BIO99-908)Peer reviewe

Towards industrial application of fungal pretreatment in 2G biorefinery: scale-up of solid-state fermentation of wheat straw

Fungal pretreatment of lignocellulosic biomass for bioethanol production is an environmental-friendly alternative to steam explosion. However, this biological pretreatment has been tested on a small scale, where most of the typical problems of solid-state fermentations (SSF), such as limited aeration or temperature control, are not observed. The main objective of this study was to assess the feasibility of the fungal pretreatment of lignocellulosic biomass (wheat straw) at a demonstration scale using the white-rot fungus Irpex lacteus to improve straw digestibility. Different configurations were evaluated for the design of a 22 L SSF reactor, but a versatile vertical design that can operate as a packed-bed and as a tray reactor was selected. The wheat straw digestibility obtained in the SSF bioreactor after 21 days of pretreatment (60.6%) was similar to that achieved on a small scale (57.9%). In addition, the most common online monitoring variables (temperature and CO2 production) correlate with the fungal action on wheat straw. As well as the weight loss, obtaining comparable results at flask and reactor scale (30 and 34.5%, respectively)Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was funded by the Spanish Ministry of Science and Innovation: Demo E2 project (PEN-120000–2009-31), as part of the National Plan of Scientific Research, Development and Technological Innovation, related to the Special Fund of the Government for enhancing the Economy and Employment, Plan E (Local investment fund for the Employment, Government of Spain), WooBAdh project (PCI2018-092866, ERA-CoBioTech program), and BioFlav-OH project (RTI2018-094482-J-I00). S.G. and G.E. received financial support from the Spanish Ministry of Science, Innovation and Universities (Grant references BES-2017–081677 and RYC2018-024846-I)S

Comprehensive investigation of the enzymatic oligomerization of esculin by laccase in ethanol : water mixtures

The enzymatic polymerization of phenolic compounds arouses increasing interest due to the production of derivatives with improved biological activity. The reaction yield, the molecular mass, the structure and the properties of synthesized polymers can be controlled by the reaction conditions such as solvent and type of enzyme and substrate. In this study, the oxidative oligomerization of esculin by laccase from Trametes versicolor was performed in the presence of ethanol, a biocompatible co-solvent for food and nutraceutical applications. The formation of a precipitate was associated with the oligomerization reaction except for the medium with 50% (v/v) ethanol, due to the low reaction yield. The evaluation of antioxidant activity of the monomer and products showed that the pellet fraction from the reaction with esculin at 2 g L−1 in acetate buffer led to the highest activities. The presence of esculin oligomers was confirmed by MALDI-TOF analysis, which identified a repetition unit of 338 Da with a degree of polymerization up to 9 as well as other oligomers, mainly in the pellet fraction, with a repetition unit of 176 Da which are attributed to be esculetin oligomers. Additionally, size exclusion chromatography (SEC) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the products.This work was financially supported by the Spanish Ministry of Economy and Competitiveness (CTQ2014-58879-JIN). Authors belong to the Galician Competitive Research Group GRC 2013-032 and to the strategic group CRETUS (AGRUP2015/02). All these programmes are co-funded by FEDER. B. G. thanks the Spanish Ministry of Economy and Competitiveness for her postdoctoral fellowship (Grant reference FPDI-2013-17341)S