Enhanced bioproduction of poly-3-hydroxybutyrate from wheat straw lignocellulosic hydrolysates

Project: EC/FP7/246449 - New tailor-made PNB-based nanocomposites for high performance applications produced from environmentally friendly production routesNOTICE: this is the author’s version of a work that was accepted for publication in New Biotechnology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in New Biotechnology, [Vol. 31, Issue 1, (January 2014)] DOI 10.1016/j.nbt.2013.10.004"Polyhydroxyalkanoates (PHAs) are bioplastics that can replace conventional petroleum derived products in various applications. One of the major barriers for their widespread introduction in the market is the higher production costs when compared with their petrochemical counterparts. In this work, a process was successfully implemented with high productivity based on wheat straw, a cheap and readily available agricultural residue, as raw material. The strain Burkholderia sacchari DSM 17165 which is able to metabolize glucose, xylose and arabinose, the main sugars present in wheat straw hydrolysates (WSH), was used. Results in shake flask showed that B. sacchari cells accumulated ca 70 % g P(3HB)/g cell-dry-weight with a yield of polymer on sugars (YP/S) of 0.18 g/g when grown on a mixture of commercial C6 and C5 sugars (control), while these values reached ca 60 % g P(3HB)/g cell-dry-weight and 0.19 g/g, respectively, when WSHs were used as carbon source. In fed-batch cultures carried out in 2L stirred tank reactors on WSH, a maximum polymer concentration of 105 g/L was reached after 61 h of cultivation corresponding to an accumulation of 72% of CDW. Polymer yield and productivity were 0.22 g P(3HB)/g total sugar consumed and 1.6 g/L. h, respectively. The selected feeding strategy successfully overcame the carbon catabolite repression phenomenon observed in sugar mixtures containing hexoses and pentoses. This is the first work describing fed-batch cultivations aiming at PHA production using real lignocellulosic hydrolysates. Additionally, the P(3HB) volumetric productivities attained are, by far, the highest achieved ever on agricultural wastes hydrolysates."U

Biodegradable polyesters from agro&industrial by-products

Poster presented at the 11th annual World Congress on Industrial Biotechnology. Studies on GRP were financed by the EU Integrated Project BIOPRODUCTION (contract nº 026515-2) and those on cellulosic hydrolysates are funded by the EU Collaborative Project BUGWORKERS (contract nº 246449). C. Almeida, J. Cavalheiro, T. Cesário and F. Ferreira were supported by Fundação para a Ciência e Tecnologia, Portugal (SFRH/BPD/26678/2006, SFRH/BD/45266/2008 and SFRH/BPD/68587/2010, IF/00442/2012). Waste glycerol was kindly provided by Torrejana, Fábrica de Biocombustíveis (Torres Vedras). Lignocellulosic hydrolysates were produced by biorefinery.de GmbH, Germany, in the framework of BUGWORKERS project.Institute for Biotechnology and Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Portugal / Biotrend S.A., Cantanhede, Portugal / Ecole Europeènne de Chimie, Polymères et Matériaux, Université de Strasbourg, Franc

Production of poly (3-hydroxybutyrate-co-4-hydroxybutyrate) by Burkholderia sacchari using wheat straw hydrolysates and gamma-butyrolactone

“NOTICE: this is the author’s version of a work that was accepted for publication in International Journal of Biological Macromolecules. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in International Journal of Biological Macromolecules, Vol. 71, Special issue, (November 2014). DOI 10.1016/j.ijbiomac.2014.04.054 ""Burkholderia sacchari DSM 17165 is able to grow and produce poly(3-hydroxybutyrate) both on hexoses and pentoses. In a previous study, wheat straw lignocellulosic hydrolysates (WSH) containing high C6 and C5 sugar concentrations were shown to be excellent carbon sources for P(3HB) production. Using a similar feeding strategy developed for P(3HB) production based on WSH, fedbatch cultures were developed aiming at the production of the copolymer P(3HB-co- 4HB) (poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) by B. sacchari. The ability of this strain to synthesize P(3HB-co-4HB) was first shown in shake flasks using gammabutyrolactone (GBL) as precursor of the 4HB units. Fed-batch cultures using glucose as carbon source (control) and GBL were developed to achieve high copolymer productivities and 4HB incorporations. The attained P(3HBco- 4HB) productivity and 4HB molar % were 0.7 g/(L·h) and 4.7 molar %, respectively. The 4HB incorporation was improved to 6.3 and 11.8 molar % by addition of 2 g/L propionic and acetic acid, respectively. When WSH were used as carbon source under the same feeding conditions, the values achieved were 0.5 g/(L·h) and 5.0 molar %, respectively. Burkholderia sacchari, a strain able to produce biopolymers based on xylose-rich lignocellulosic hydrolysates, is for the first time reported to produce P(3HB-co-4HB) using gamma butyrolactone as precursor."This work has received funding from the European Union 7th Framework Programme (FP7/2007-2013) under Grant Agreement number 246449 / Project: Bugworkers - New tailor-made PHB-based nanocomposites for high performance applications produced from environmentally friendly production routes.Financial support: Fundação para a Ciência e Tecnologia, Portugal (fellowships SFRH/BPD/68587/2010 and SFRH/BPD/26678/2006)

Nationwide treatment and outcomes of intrahepatic cholangiocarcinoma

Background: Most data on the treatment and outcomes of intrahepatic cholangiocarcinoma (iCCA) derives from expert centers. This study aimed to investigate the treatment and outcomes of all patients diagnosed with iCCA in a nationwide cohort. Methods: Data on all patients diagnosed with iCCA between 2010 and 2018 were obtained from the Netherlands Cancer Registry. Results: In total, 1747 patients diagnosed with iCCA were included. Resection was performed in 292 patients (17%), 548 patients (31%) underwent palliative systemic treatment, and 867 patients (50%) best supportive care (BSC). The OS median and 1-, and 3-year OS were after resection: 37.5 months (31.0–44.0), 79.2%, and 51.6%,; with systemic therapy, 10.0 months (9.2–10.8), 38.4%, and 5.1%, and with BSC 2.2 months (2.0–2.5), 10.4%, and 1.3% respectively. The resection rate for patients who first presented in academic centers was 33% (96/292) compared to 13% (195/1454) in non-academic centers (P < 0.001). Discussion: Half of almost 1750 patients with iCCA over an 8 year period did not receive any treatment with a 1-year OS of 10.4%. Three-year survival was about 50% after resection, while long-term survival was rare after palliative treatment. The resection rate was higher in academic centers compared to non-academic centers

Crescimento de Xanthobacter Py 2 em varios alcenos; actividade destas celulas relativamente aos epoxi-alcanos

This thesis addresses the enantiomeric resolution of epoxides by resting 1 pentene grown Xanthobacter Py 2 cells. The strain had been originally isolated on propene. Growth on 1 pentene as sole carbon source was obtained after a lengthy adaptation period, during which cells were repeatedly subcultured with the addition of yeast extract at the intermediate stages. Batch production of the bio catalyst was optimised, resulting in a culture density of 0.63 gdw / L with 19% of the sealed flask occupied by broth (1 pentene is gaseous at 30 Deg C), using an initial 1 pentene concentration of 0.1% (v/v). The biomass yield on 1 pentene was 0.49 Ceq/Ceq. Problems associated with the toxicity of the epoxides towards the cells and also with the low solubility and instability of epoxides in water were solved by implementing a two phase biotransformation system, consisting of phosphate buffer containing the freely suspended cells, and a biocompatible organic substrate reservoir (iso-octane or n-dodecane). A maximum specific 1,2 apoxyhexane conversion rate of 25 nmol / min mg protein was attained when cells harvested from a batch fermentation in the late exponential phase were used. In this biphasic system, the epoxide conversion capacity of the whole cells was limited, even in the presence of co-substrates. Substitution of the buffer by mineral medium resulted in growth of the strain (using the epoxide as carbon and energy source) and in a enhanced epoxide conversion capacity of the system. Under these conditions, re-use of the bio catalyst was successfully achievedAvailable from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1249-074 Lisboa, Portugal / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga

Noordlyk Halvrond

Deze kaart van de noordelijke sterrenhemel (en de bijbehorende kaart van de zuidelijke sterrenhemel) was oorspronkelijk ontworpen door Pieter Nieuwland (1764-1794), hoogleraar sterrenkunde in Leiden, maar moest door diens vroegtijdig overlijden door Van Beeck Calkoen voltooid worden

Zuidlyk Halvrond

Deze kaart van de zuidelijke sterrenhemel (en de bijbehorende kaart van de noordelijke sterrenhemel) was oorspronkelijk ontworpen door Pieter Nieuwland (1764-1794), hoogleraar sterrenkunde in Leiden, maar moest door diens vroegtijdig overlijden door Van Beeck Calkoen voltooid worden

Towards a cost effective strategy for cutinase production by a recombinant Saccharomyces cerevisiae: strain physiological aspects

Although the physiology and metabolism of the growth of yeast strains has been extensively studied, many questions remain unanswered where the induced production of a recombinant protein is concerned. This work addresses the production of a Fusarium solani pisi cutinase by a recombinant Saccharomyces cerevisiae strain induced through the use of a galactose promoter. The strain is able to metabolise the inducer, galactose, which is a much more expensive carbon source than glucose. Both the transport of galactose into the cell—required for the induction of cutinase production—and galactose metabolism are highly repressed by glucose. Different fermentation strategies were tested and the culture behaviour was interpreted in view of the strain metabolism and physiology. A fed-batch fermentation with a mixed feed of glucose and galactose was carried out, during which simultaneous consumption of both hexoses was achieved, as long as the glucose concentration in the medium did not exceed 0.20 g/l. The costs, in terms of hexoses, incurred with this fermentation strategy were reduced to 23% of those resulting from a fermentation carried out using a more conventional strategy, namely a fed-batch fermentation with a feed of galactose.info:eu-repo/semantics/publishedVersio

Major complications and mortality after resection of intrahepatic cholangiocarcinoma: A systematic review and meta-analysis

Background: Evaluation of morbidity and mortality after hepatic resection often lacks stratification by extent of resection or diagnosis. Although a liver resection for different indications may have technical similarities, postoperative outcomes differ. The aim of this systematic review and meta-analysis was to determine the risk of major complications and mortality after resection of intrahepatic cholangiocarcinoma. Methods: Meta-analysis was performed to assess postoperative mortality (in-hospital, 30-, and 90-day) and major complications (Clavien-Dindo grade ≥III). Results: A total of 32 studies that reported on 19,503 patients were included. Pooled in-hospital, 30-day, and 90-day mortality were 5.9% (95% confidence interval 4.1–8.4); 4.6% (95% confidence interval 4.0–5.2); and 6.1% (95% confidence interval 5.0–7.3), respectively. Pooled proportion of major complications was 22.2% (95% confidence interval 17.7–27.5) for all resections. The pooled 90-day mortality was 3.1% (95% confidence interval 1.8–5.2) for a minor resection, 7.4% (95% confidence interval 5.9–9.3) for all major resections, and 11.4% (95% confidence interval 6.9–18.7) for extended resections (P = .001). Major complications were 38.8% (95% confidence interval 29.5–49) after a major hepatectomy compared to 11.3% (95% confidence interval 5.0–24.0) after a minor hepatectomy (P = .001). Asian studies had a pooled 90-day mortality of 4.4% (95% confidence interval 3.3–5.9) compared to 6.8% (95% confidence interval 5.6–8.2) for Western studies (P = .02). Cohorts with patients included before 2000 had a pooled 90-day mortality of 5.9% (95% confidence interval 4.8–7.3) compared to 6.8% (95% confidence interval 5.1–9.1) after 2000 (P = .44). Conclusion: When informing patients or comparing outcomes across hospitals, postoperative mortality rates after liver resection should be reported for 90-days with consideration of the diagnosis and the extent of liver resection