Phytatec UK Ltd.

Aberystwyth, United Kingdom

Phytatec UK Ltd.

Aberystwyth, United Kingdom
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Powell T.,University of Birmingham | Bowra S.,Phytatec UK Ltd. | Cooper H.J.,University of Birmingham
Journal of the American Society for Mass Spectrometry | Year: 2017

Previously we have shown that subcritical water may be used as an alternative to enzymatic digestion in the proteolysis of proteins for bottom-up proteomics. Subcritical water hydrolysis of proteins was shown to result in protein sequence coverages greater than or equal to that obtained following digestion with trypsin; however, the percentage of peptide spectral matches for the samples treated with trypsin were consistently greater than for those treated with subcritical water. This observation suggests that in addition to cleavage of the peptide bond, subcritical water treatment results in other hydrolysis products, possibly due to modifications of amino acid side chains. Here, a model peptide comprising all common amino acid residues (VQSIKCADFLHYMENPTWGR) and two further model peptides (VCFQYMDRGDR and VQSIKADFLHYENPTWGR) were treated with subcritical water with the aim of probing any induced amino acid side-chain modifications. The hydrolysis products were analyzed by direct infusion electrospray tandem mass spectrometry, either collision-induced dissociation or electron transfer dissociation, and liquid chromatography collision-induced dissociation tandem mass spectrometry. The results show preferential oxidation of cysteine to sulfinic and sulfonic acid, and oxidation of methionine. In the absence of cysteine and methionine, oxidation of tryptophan was observed. In addition, water loss from aspartic acid and C-terminal amidation were observed in harsher subcritical water conditions. [Figure not available: see fulltext.]. © 2017, The Author(s).

Roque R.,University of Birmingham | Bowra S.,Phytatec UK Ltd. | Santos R.,University of Birmingham
Fuel Processing Technology | Year: 2015

Lignin was isolated with subcritical water:ethanol:CO2 (Sub-CW) from biorefinery biomasses, such as giant reed (AD) and miscanthus (MG), with recovery yields about 30% on Klason lignin. Their structural composition assessed by IR and NMR techniques, as well as Derivatization Followed by Reductive Cleavage (DFRC/GC-MS). The 2D HSQC-NMR spectra elucidated that the Sub-CW extracts contained different lignin dimers and co-extracted carbohydrates. The DFRC/GC-MS revealed that syringyl molecules were more abundant in AD, while guaiacyl monomers were predominant in MG. Lignin residues were derivatized with phospholane to quantitatively estimate the amount of OH groups by 31P NMR, showing a marked predominance of aliphatic units for both lignins, due to the presence of either hydroxyls in lignin side-chain or residual carbohydrates. Lignin residues derivatized with phospholane allowed to record 31P-DOSY NMR spectra. AD-lignin showed a smaller diffusivity constant than for MG-substrate, possibly because of the larger content of disaccharides in MG lignin. We showed that the molecular composition of lignin isolated by the Sub-CW technique may differ depending on the type of biomass used for the extraction, suggesting a different industrial application of lignin from various biomass. © 2015 Elsevier B.V.

Conventional biorefineries target production of a single product stream utilising a dedicated crop based feedstock. Such processes offer limited commercial viability, generate significant waste streams and raise ethical and sustainability concerns with regards to the feedstocks used (competition with food crops & genetic modification to improve yield). Paralleling conventional petroleum refineries, integrated biorefining overcomes these limitations through utilisation of the wider biomass components to deriving multiple bulk and high value product streams (zero waste processes), thereby achieving commercial competitiveness in line with conventional refineries and enabling a transition from dedicated non-food crops to low cost, readily available and sustainable biomass. The Phytatec Technology Platform is built on this concept, combining environmentally benign critical fluid processes with the selectivity and efficiency of enzyme transformations. The BREW-PACK project will apply and further develop the existing Phytatec platform for the integrated biorefining of brewers spent grain BSG (a readily available and low cost biomass feedstock), building on two core areas of innovation: - Application and further development of existing critical fluid processes for the sequential hydrolysis and fractionation of BSG to lipophilic, proteinaceous and polar (carbohydrate rich) primary material fractions - New know-how, strategies and technological development for the separation and knowledge based transformation of BSG proteins, enabling development of multi-layer biopolymer films demonstrating enhanced performance and functionality suitable for innovative high value packaging applications The project will conclude with a desk based feasibility study for design of a pilot and subsequent large scale plant, targeting establishment of supply chains worth over 72 million, generating ~450 new jobs and providing potential benefit to over 9000 wider SMEs.

Baig M.N.,University of Birmingham | Santos R.C.D.,University of Birmingham | Zetzl C.,TU Hamburg - Harburg | King J.,University of Arkansas | And 2 more authors.
Enzyme and Microbial Technology | Year: 2011

Supercritical fluids offer environmental advantages over chemical solvents, while providing enhanced separation and chemical selectivity. The use of supercritical fluids for the recovery of products from biomass and the transformation of selected molecules (to add value) was studied. Free fatty acids were bio-catalytically transformed to fatty acid esters using lipase within a supercritical fluid environment. A central composite rotatable design was used to evaluate the influence of operating conditions on the enzymatic esterification process and a response surface equation was optimized to identify the most favourable process conditions for maximum free fatty acid conversion. Based on the model equation the process conditions under which it was predicted a yield of 100% esters could be obtained were: pressure 200bar, temperature 60°C, ethanol concentration 2.0M, enzyme concentration 11wt.% and time 60min. Experiments conducted under these conditions gave an ester yield of 94.3% (close to predicted results). The activity per unit mass of biocatalyst was found to be 1585μmol/min/g cat. The results support the use of supercritical fluids for process integration. © 2011 Elsevier Inc.

Bahari A.,University of Birmingham | Baig M.N.,University of Birmingham | Leeke G.A.,University of Birmingham | Bowra S.,Phytatec UK Ltd | Santos R.C.D.,University of Birmingham
Industrial Crops and Products | Year: 2014

Cider lees, a microbial by-product of the cider industry which is primarily comprised yeast cells was subjected to subcritical water mediated hydrolysis using a batch tubular reactor over a temperature range of 175-275. °C. The efficacy of subcritical water to hydrolyse the polysaccharides and mannoproteins in the yeast's cell wall to monosaccharides and for the glucose and mannose to be dehydrated to 5-hydroxymethylfurfural (HMF) was investigated in a non-catalysed reaction using a consecutive first order kinetic model. Results suggest that the cider yeast cell wall, which is backboned by milder bonds, was decomposed at lower temperatures when compared to cellulose hydrolysis under the same conditions. Glucose and mannose formation was observed at temperatures as low as 175. °C and their conversion to HMF at 225. °C resulted the yield of more than 12%, based on the crude feedstock. Reaction rates for other decomposition routes were also calculated and discussed using the developed model. © 2014 Elsevier B.V.

Roque R.M.N.,University of Birmingham | Baig M.N.,University of Birmingham | Leeke G.A.,University of Birmingham | Bowra S.,Phytatec UK Ltd. | Santos R.C.D.,University of Birmingham
Resources, Conservation and Recycling | Year: 2012

The present study was undertaken to evaluate the impact of sub-critical water (Sub-CW) processing parameters, such as temperature and biomass:Sub-CW:ethanol:CO 2 ratio, in order to optimise the delignification of the Miscanthus χ giganteus, a lignocellulosic biomass. The percentage lignin solubilised (delignification) was calculated by measuring the amount of lignin, using the Klason assay, that remained in the insoluble fraction. The amount of biomass solubilised was determined by calculating the difference between the initial weight of biomass and the weight of the residual insoluble fraction. Experimental results showed a maximum solubilisation and delignification of 53% and 86% respectively at 200 °C and biomass/solvent ratio of 1:100, i.e., 2.5 g in 250 ml of water:ethanol mixture (50:50). Scanning Electron Microscopy (SEM) images were taken to analyse the effect of hydrolysis on cellulose fibres structure. The results showed the residual fibres appeared intact, with some lignin globules attached to them. Consequently, it was concluded that the use of Sub-CW:ehanol:CO 2 mediated hydrolysis under the stated operating conditions supported delignification without destroying the cellulose fibres. © 2011 Elsevier B.V. All rights reserved.

PubMed | Phytatec U.K. Ltd. and University of Birmingham
Type: Journal Article | Journal: Analytical chemistry | Year: 2016

Subcritical water is an emerging tool in the processing of bioorganic waste. Subcritical water is an environmentally benign solvent which has the potential to provide an alternative to traditional methods of protein hydrolysis without the inclusion of expensive acids or enzymes. To date, most studies on the subcritical water mediated hydrolysis of proteins have focused on the production of amino acids, rather than the intermediate peptides. Here, we investigate the specificity of subcritical water with respect to the production of peptides from three model proteins, hemoglobin, bovine serum albumin, and -casein, and compare the results with enzymatic digestion of proteins by trypsin. In addition, the effect of subcritical water (SCW) treatment on two protein post-translational modifications, disulfide bonds and phosphorylation, was investigated. The results show that high protein sequence coverages (>80%) can be obtained following subcritical water hydrolysis. These are comparable to those obtained following treatment with tryspin. Under mild subcritical water conditions (160 C), all proteins showed favored cleavage of the Asp-X bond. The results for -casein revealed favored cleavage of the Glu-X bond at subcritical water temperatures of 160 and 207 C. That was similarly observed for bovine serum albumin at a subcritical water temperature of 207 C. Subcritical water treatment results in very limited cleavage of disulfide bonds. Reduction and alkylation of proteins either prior to or post subcritical water treatment improve reported protein sequence coverages. The results for phosphoprotein -casein show that, under mild subcritical water conditions, phosphorylation may be retained on the peptide hydrolysis products.

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