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In this work, we elaborate on the concept of process authenticity, which intuitively corresponds to the validity of all process steps and their proper binding. It represents the most exciting forefront of distributed ledger technology research concerning the primary challenge of reliably connecting distributed ledger networks to the physical context it must operate. More in detail, the paper describes a novel methodological approach to ensure the authenticity of business processes through blockchain and several security mechanisms applied to the digital twins of the actual processes. We illustrate difficulties and opportunities deriving from implementing process authenticity in concrete case studies in which we were involved as software designers belonging to three critical application domains: document dematerialization, e-voting, and healthcare. [ABSTRACT FROM AUTHOR]

Vinylphenol reductase of Dekkera bruxellensis , the characteristic enzyme liable for “Brett” sensory modification of wine, has been recently recognized to belong to the short chain dehydrogenases/reductases family. Indeed, a preliminary biochemical characterisation has conferred to the purified protein a dual significance acting as superoxide dismutase and as a NADH-dependent reductase. The present study aimed for providing a certain identification of the enzyme by cloning the VPR gene in S. cerevisiae , a species not producing ethyl phenols. Transformed clones of S. cerevisiae resulted capable of expressing a biologically active form of the heterologous protein, proving its role in the conversion of 4-vinyl guaiacol to 4-ethyl guaiacol. A VPR specific protein activity of 9 ± 0.6 mU/mg was found in crude extracts of S. cerevisiae recombinant strain. This result was confirmed in activity trials carried out with the protein purified from transformant cells of S. cerevisiae by a his-tag purification approach; in particular, VPR-enriched fractions showed a specific activity of 1.83 ± 0.03 U/mg at pH 6.0. Furthermore, in agreement with literature, the purified protein behaves like a SOD, with a calculated specific activity of approximatively 3.41 U/mg. The comparative genetic analysis of the partial VPR gene sequences from 17 different D. bruxellesis strains suggested that the observed polymorphism (2.3%) and the allelic heterozygosity state of the gene do not justify the well described strain-dependent character in producing volatile phenols of this species. Actually, no correlation exists between genotype membership of the analysed strains and their capability to release off-flavours. This work adds valuable knowledge to the study of D. bruxellensis wine spoilage and prepare the ground for interesting future industrial applications. [ABSTRACT FROM AUTHOR]

Non-lypolitic esterases are carboxylester hydrolases with preference for the hydrolysis of water-soluble esters bearing short-chain acyl residues. The potential of esterases as enantioselective biocatalysts has enlarged in the last few years due to the progresses achieved in different areas, such as screening methodologies, overproduction of recombinant esterases, structural information useful for understanding the rational behind enantioselectivity, and efficient methods in protein engineering. Contributions of these complementary know-hows to the development of new robust enantioselective esterases are critically discussed in this review. [ABSTRACT FROM AUTHOR]

Background Old Yellow Enzymes (OYEs) are flavin-dependent enoate reductases (EC 1.6.99.1) that catalyze the stereoselective hydrogenation of electron-poor alkenes. Their ability to generate up to two stereocenters by the trans-hydrogenation of the C = C double bond is highly demanded in asymmetric synthesis. Isolated redox enzymes utilization require the addition of cofactors and systems for their regeneration. Microbial whole-cells may represent a valid alternative combining desired enzymatic activity and efficient cofactor regeneration. Considerable efforts were addressed at developing novel whole-cell OYE biocatalysts, based on recombinant Saccharomyces cerevisiae expressing OYE genes. Results Recombinant S. cerevisiae BY4741ΔOye2 strains, lacking endogenous OYE and expressing nine separate OYE genes from non-conventional yeasts, were used as whole-cell biocatalysts to reduce substrates with an electron-poor double bond activated by different electronwithdrawing groups. Ketoisophorone, α-methyl-trans-cinnamaldehyde, and trans-β-methyl- β-nitrostyrene were successfully reduced with high rates and selectivity. A series of four alkyl-substituted cyclohex-2-enones was tested to check the versatility and efficiency of the biocatalysts. Reduction of double bond occurred with high rates and enantioselectivity, except for 3,5,5-trimethyl-2-cyclohexenone. DFT (density functional theory) computational studies were performed to investigate whether the steric hindrance and/or the electronic properties of the substrates were crucial for reactivity. The three-dimensional structure of enoate reductases from Kluyveromyces lodderae and Candida castellii, predicted through comparative modeling, resulted similar to that of S. cerevisiae OYE2 and revealed the key role of Trp116 both in substrate specificity and stereocontrol. All the modeling studies indicate that steric hindrance was a major determinant in the enzyme reactivity. Conclusions The OYE biocatalysts, based on recombinant S. cerevisiae expressing OYE genes from nonconventional yeasts, were able to differently reduce the activated double bond of enones, enals and nitro-olefins, exhibiting a wide range of substrate specificity. Moreover whole-cells biocatalysts bypassed the necessity of the cofactor recycling and, tuning reaction parameters, allowed the synthetic exploitation of endogenous carbonyl reductases. Molecular modeling studies highlighted key structural features for further improvement of catalytic properties of OYE enzymes. [ABSTRACT FROM AUTHOR]

Abstract: Cell-bound lipases of dry mycelium of Aspergillus oryzae were used in organic solvent for the resolution of racemic flurbiprofen by direct esterification with ethanol in a flow-chemistry reactor. Under flow conditions a significant reduction of the reaction time and an increase of the enantioselectivity were achieved compared to the batch mode. Moreover, the process was implemented by adding an in-line purification step integrated with the racemization of the unreacted flurbiprofen directly into a polymer-supported resin. [Copyright &y& Elsevier]

Abstract: The lipase-catalysed kinetic resolution of flurbiprofen was performed in a flow-chemistry reactor allowing for a significant reduction of the reaction time compared to the classical batch method. The process was implemented by adding an in-line purification step of the exiting solution, consisting in a catch and release protocol, which allows easy separation and recovery of both (S)-flurbiprofen and (R)-flurbiprofen butyl ester with an enantiomeric excess ≥90% and a chemical purity >98%. [Copyright &y& Elsevier]

The article gives an overview of the preparative methods for the oxidation of alcohols available for organic chemists highlighting the advantages and limitations of the bioprocesses. It outlines some of the drawbacks of alcohol oxidation at preparative scale including cofactor recycling. It cites the difference between dehydrogenases and oxidases in terms of the way cofactors are re-oxidized. Also discussed are the classes of enzymes that catalyze alcohol oxidation into aldehydes.

Abstract: Old yellow enzymes (OYEs, EC 1.6.99.1) are flavin-dependent oxidoreductases that catalyze the stereoselective trans-hydrogenation of the double bond, representing a promising alternative to metal-based catalysis. Bioconversion of ketoisophorone (KIP) by 28 non-conventional yeasts belonging to 16 different species was investigated. Growing cells of most of the strains reduced KIP via OYE and showed high stereoselectivity, producing R-levodione as major product. Competition by carbonyl reductase (CR) activity was observed in several strains. The best performing yeasts belong to Candida castellii, Kazachstania spencerorum and Kluyveromyces marxianus exhibited yields of levodione ≥77% up to 95% e.e., and. Candida freyschussii, the sole strain lacking the OYE gene, reduced KIP only to unsaturated alcohols via CR. Nine unedited OYE genes were cloned, sequenced, and heterologously expressed in Saccharomyces cerevisiae BY4741ΔOye2, a mutant that showed negligible OYE and CR activities. Compared with the corresponding wild-type yeasts, growing cells of the recombinant strains bioconverted KIP with improved yields of OYE products, minor competition by CR activity, and lower enantioselectivity. In particular, resting cells of recombinant S. cerevisae presented the best performance in KIP bioconversion. Based on the results herein reported, selected strains of non-conventional yeasts and novel OYE genes can be profitably used as innovative biocatalysts in asymmetric reductions. [Copyright &y& Elsevier]

Abstract: Human d-amino acid oxidase (hDAAO) is a flavoprotein that plays a key role in the pathophysiology of schizophrenia. So far, the biochemical characterization of this enzyme has been hampered by the difficulty of expressing it in a common heterologous host such as Escherichia coli. Increasing amounts of recombinant hDAAO are indeed required for the investigation of its structure–function relationships and for the screening of new inhibitors to be used in the treatment of schizophrenia. A recombinant hDAAO has been over-expressed in BL21(DE3)Star E. coli cells. By alternating screenings of medium components at flask level and investigating physiological parameters in 2L controlled batch fermentations, an improved, robust and scalable microbial process was set up giving almost a 40- and 4-fold improvement in volumetric productivity and specific activity, respectively. Under these conditions ∼770U/L culture hDAAO with a specific activity of ∼0.4U/mg protein and a specific productivity of 24.9U/g biomass were produced. Optimization of medium ingredients, of the time and the amount of inducer’s addition, pH control at the moment of induction and harvest, low mechanical shear stress regime during recombinant protein production, represent the factors concurring to achieve the reported expression level. Notably, this expression level is higher than any previously described production of hDAAOs. A yield of 100mg of pure hDAAO/L culture thus became available in comparison to the 1–10mg/L previously reported. [Copyright &y& Elsevier]

Image Coregistration for InSAR processing is a time-consuming procedure that is usually processed in batch mode. With the availability of low-energy GPU accelerators, processing at the edge is now a promising perspective. Starting from the individuation of the most computationally intensive kernels from existing algorithms, we decomposed the cross-correlation problem from a multilevel point of view, intending to design and implement an efficient GPU-parallel algorithm for multiple settings, including the edge computing one. We analyzed the accuracy and performance of the proposed algorithm—also considering power efficiency—and its applicability to the identified settings. Results show that a significant speedup of InSAR processing is possible by exploiting GPU computing in different scenarios with no loss of accuracy, also enabling onboard processing using SoC hardware. [ABSTRACT FROM AUTHOR]

Abstract: The enantioselective reduction of tibolone into the corresponding 3α-hydroxy or 3β-hydroxy metabolite can be controlled by choosing suited strains of yeasts and biotransformation conditions. A restricted screening performed among 52 yeasts showed that the 3α-epimer was preferentially obtained with high epimeric purity with various strains (i.e. with Kluyveromyces lactis CBS 2359), while only Saccharomyces cerevisiae CBS 3093 gave the 3β-epimer as major product. The reduction of tibolone with K. lactis CBS 2359 and S. cerevisiae CBS 3093 was optimised. S. cerevisiae CBS 3093 furnished a 96:4 ratio of 3β/3α with complete molar conversion within 72h when the initial concentration of substrate was below 2.5g/L. K. lactis CBS 2359 gave a 99:1 ratio of 3α/3β with complete conversion in 64h. [Copyright &y& Elsevier]

Abstract: The esterification of (R, S)-1,2-O-isopropylideneglycerol catalysed by dry mycelia of different moulds in organic solvent was studied. Dry mycelium of Rhizopus oryzae CBS 112.07 and Aspergillus oryzae MIM gave the (R)-ester with moderate optical purity; the kinetic data of the esterification with butyric acid in n-heptane showed an enantiomeric ratio of 3.4 with Rhizopus oryzae and 8.0 with Aspergillus oryzae. The esterification catalysed by Aspergillus oryzae was performed on larger scale (operative volume 2.3l) allowing for the production of 2.3gl−1 of (R)-IPG butyrate with an e.e.=56% and a molar conversion of 52%. The enantiomerically enriched ester was hydrolysed with thermally-treated cells of Bacillus coagulans: the (S)-ester was obtained as enantiomerically pure molecule, while the alcohol was recovered with e.e.=90%. [Copyright &y& Elsevier]

Abstract: An improved procedure for the microbial hydroxylations of dehydroepiandrosterone (DHEA, 1) and 15β,16β-methylene-dehydroepiandrosterone (2) was studied using whole cells of Botryodiplodia malorum and Colletotrichum lini. C. lini catalyzed 7α- and 15α-hydroxylation of 1 and 7α-hydroxylation of 2, while B. malorum gave 7β-hydroxylation of both the substrates. The stability of the enzymatic activity was higher in the presence of co-substrates (i.e., glucose or mannitol) allowing for repeated batches of the biotransformations. The yields of 7α,15α-dihydroxy-1 production were improved obtaining 5.8gl−1 (recovered product) from 7.0gl−1 of substrate. The structures of the hydroxylated products were assigned by a combination of two-dimensional NMR proton–proton and proton–carbon correlation techniques. [Copyright &y& Elsevier]

Abstract: A new chemoenzymatic synthesis of d-cloprostenol based on the biocatalytical resolution of anti-2-oxotricyclo[2.2.1.0]heptan-7-carboxylic acid 1 has been developed. The resolution was attempted by different approaches: esterification or reduction of the acid and hydrolysis or reduction of the corresponding esters. The most efficient method proved to be the reduction of the propyl esters of 1 catalysed by the yeast Kluyveromyces marxianus, which allowed for the recovery of the enantiomerically pure ester of anti-2-oxotricyclo[2.2.1.0]heptan-(R)-7-carboxylic acid (R)-3 at 60% molar conversion of 3.0g/l of racemic substrate acid under optimised conditions. anti-2-Oxotricyclo[2.2.1.0]heptan-(R)-7-carboxylic acid was obtained by alkaline hydrolysis and employed for the synthesis of d-cloprostenol. [Copyright &y& Elsevier]

Abstract: The enantioselective hydrolysis of different (RS)-1,2-O-isopropylidene glycerol esters has been achieved with whole cells of Bacillus coagulans NCIMB 9365 furnishing the (S)-alcohol as the major enantiomer. The reaction is catalysed by a thermostable cell-bound carboxylesterase and improvement of the enantioselectivity has been achieved by heat treatment of the whole cells, which causes the knock-outs a non-enantioselective competing enzyme. Thermally-treated cells hydrolysed (RS)-1,2-O-isopropylidene glycerol esters with high enantioselectivity, the highest enantiomeric ratio (80–100) being observed for the benzoate. The biocatalyst displayed good stability and could be re-used after filtration for 12 cycles before showing significant loss of activity; repeated biotransformation batches allowed the recovery of 9.55g/L of enantiomerically pure (S)-isopropylideneglycerol benzoate starting from 24.0g/L of the racemic mixture. [Copyright &y& Elsevier]

Abstract: Echinocandin acylase from Actinoplanes utahensis NRRL 12052 (ECB deacylase) was used for the hydrolysis of capsaicins (trans-8-methyl-N-vanillyl-6-nonenamide and 8-methyl-N-vanillyl-6-nonanamide) into vanillylamine. Caspaicins were extracted from Capsicum annuum var. Red Cayenne. The enzyme was partially purified and used for improving molar conversion and reaction rate of the biotransformation. Under optimised conditions, the preparative biotransformation of 8.2mM capsaicins on 200ml scale allowed for 92% molar conversions and 59% of recovered vanillylamine. [Copyright &y& Elsevier]

An abstract of the article "ChemInform Abstract: Biocatalytic Oxidation of 1,4-Diols and γ -Lactols into γ-Lactones: Application to Chemoenzymatic Synthesis of Drospirenone (IV)" by Diego Romano and colleagues is presented.

Review: 94 refs. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose (BC) is a highly versatile biopolymer currently pursued as a material of choice in varied themes of biomedical and material science research fields. With the aim to extend the biotechnological applications, the genetic tractability of the BC producers within the Komagataeibacter genus and its potential as an alternative host chassis in synthetic biology have been extensively studied. However, such studies have been largely focused on the model Komagataeibacter spp. Here, we present a novel K. intermedius strain capable of utilizing glucose, and glycerol sources for biomass and BC synthesis. Genome assembly identified one bacterial cellulose synthetase (bcs) operon containing the complete gene set encoding the BC biogenesis machinery (bcsI) and three additional copies (bcsII–IV). Investigations on the genetic tractability confirmed plasmid transformation, propagation of vectors with pBBR1 and p15A origin of replications and constitutive and inducible induction of recombinant protein in K. intermedius ENS15. This study provides the first report on the genetic tractability of K. intermedius, serving as starting point towards future genetic engineering of this strain. [ABSTRACT FROM AUTHOR]

Several Remote Sensing applications in Hyperspectral Imaging rely on Artificial Intelligence techniques, particularly Deep Neural Networks, which often outperform other algorithms. However, despite their effectiveness, these techniques are considered opaque for the non-linearity of the underlying model, making a conscious results interpretation difficult even for experts in the application field. The present work aims to describe the results of our experiments toward Explainable Artificial Intelligence techniques for hyperspectral remote sensing image classification in Edge Computing environments. The proposed technique extends the traditional 2D Gradient-weighted Class Activation Mapping (Grad-CAM) to 3D Convolutional Neural Networks. Moreover, we use spectral-cumulative Grad-CAM and class probability as complementary methods. The experimental results confirm that the observer can interpret the choices made within neural network layers by visualizing the activation volumes provided by the proposed method. [Display omitted] • Image classification can benefit from the interaction between Edge Computing and Artificial Intelligence. • Explainable Artificial Intelligence can improve the interpretability of the results achieved through Neural Networks. • The proposed XAI method extends traditional 2D Grad-CAM to 3D CNNs. • The results confirm that the observer can better understand the choices made within neural network layers. [ABSTRACT FROM AUTHOR]

Optimized recombinant whole cells of E. coli bearing CYP153A6 were employed for catalyzing the hydroxylation of different monoterpene derivatives. In most cases, high selectivity was observed with exclusive hydroxylation of the allylic methyl group bound to the aliphatic ring. In the case of (R)- and (S)-carvone, hydroxylation occurred also on the other allylic methyl group, although to a lesser extent. Biotransformations carried out in fed-batch mode on (S)-limonene and α-terpineol showed that recombinant whole cells retained activity for at least 24 h, allowing for the recovery of 3.25 mg mL−1 of (S)-perillyl alcohol and 5.45 mg mL−1 of 7-hydroxy-α-terpineol, respectively. Keypoints: Different monoterpenes can be regioselectively hydroxylated by CYP153A6 monooxygenase The biotransformation with whole cells is complementary to chemical oxyfunctionalization Fed-batch biotransformations have been applied for preparative purposes [ABSTRACT FROM AUTHOR]

A new synthetic method for the one-pot preparation of aldoximes in water was developed; the method is based on the combination of the enzymatic oxidation of primary alcohols to aldehydes using different acetic acid bacteria and in situ condensation of the aldehydes with hydroxylamine. [ABSTRACT FROM AUTHOR]

Abstract: Water/organic solvent two-liquid-phase systems have been successfully applied in the synthesis of enantiomerically pure (S)-benzoin through two different methodologies catalysed by whole cells from the non-conventional yeast Pichia glucozyma: the stereoselective monoreduction of benzil and the deracemisation of benzoin. The presence of the organic solvent influences the redox systems implied in the reactions, avoiding the formation of the corresponding diols, increasing the enantioselectivity and allowing the easy isolation of the products in high yields and excellent enantiomeric excesses. The use of both strategies has been extended to the preparation of different chiral benzoin derivatives. [Copyright &y& Elsevier]

Abstract: Mycelia containing carboxyl-esterases, a novel source of enzymes, have been investigated in the hydrolytic kinetic resolution of one type of tert-alcohols, α,α-disubstituted cyanohydrins. This class of enzymes was found to be both active and selective towards these tert-alcohols, giving E-values as high as 42. [Copyright &y& Elsevier]

The current work aims to produce nanoparticle-infused starch-based bioactive thermoplastic packaging films. The FeO and ZnO nanoparticles were examined to be potential active ingredients for the production of nanoparticle-infused bioactive thermoplastic packaging films. The bio-thermoplastic films infused with FeO and ZnO nanoparticles showed high oxygen scavenging and antimicrobial activity, respectively. Consecutively, both films were combined to form a double-layer Nano-Biothermoplastic packaging system for food preservation. The distribution and diffusion of nanoparticles in starch-based films were examined to be influenced by the amorphous character of starch and the swelling index of the film, respectively. The amorphous property of starch molecules showed a masking effect on the crystalline characteristics of nanoparticles in Nano-Biothermoplastic films. The diffusion of nanoparticles from the Nano-Biothermoplastic packaging system was found to influence the microbial, chemical, and color characteristics of mutton and chicken meat stored at 4 °C. [Display omitted] • The FeO and ZnO Nps were found to be potential active ingredient for food packaging. • The amorphous regions of starch were found to immobilize the FeO and ZnO Nps. • The crystalline nature of Nps was masked by amorphous regions of starch molecules. • The double layer Nano-Biothermoplastic films were identified as potential food package. [ABSTRACT FROM AUTHOR]

Applying a circular economy approach, this research explores the use of cheese whey permeate (CWP), by-product of whey ultrafiltration, as cheap substrate for the production of bacterial cellulose (BC) and Sakacin-A, to be used in an antimicrobial packaging material. BC from the acetic acid bacterium Komagataeibacter xylinus was boosted up to 6.77 g/L by supplementing CWP with β-galactosidase. BC was then reduced to nanocrystals (BCNCs, 70% conversion yield), which were then conjugated with Sakacin-A, an anti-Listeria bacteriocin produced by Lactobacillus sakei in a CWP based broth. Active conjugates (75 Activity Units (AU)/mg), an innovative solution for bacteriocin delivery, were then included in a coating mixture applied onto paper sheets at 25 AU/cm2. The obtained antimicrobial food package was found effective in reducing Listeria population in storage trials carried out on a fresh Italian soft cheese (named "stracchino") intentionally inoculated with Listeria. Production costs of the active material have been mainly found to be associated (90%) to the purification steps. Setting a maximum prudential 50% cost reduction during process up-scaling, conjugates coating formulation would cost around 0.89 €/A4 sheet. Results represent a practical example of a circular economy production procedure by using a food industry by-product to produce antimicrobials for food preservation. [ABSTRACT FROM AUTHOR]

The K-means algorithm is one of the most popular algorithms in Data Science, and it is aimed to discover similarities among the elements belonging to large datasets, partitioning them in K distinct groups called clusters. The main weakness of this technique is that, in real problems, it is often impossible to define the value of K as input data. Furthermore, the large amount of data used for useful simulations makes impracticable the execution of the algorithm on traditional architectures. In this paper, we address the previous two issues. On the one hand, we propose a method to dynamically define the value of K by optimizing a suitable quality index with special care to the computational cost. On the other hand, to improve the performance and the effectiveness of the algorithm, we propose a strategy for parallel implementation on modern multicore CPUs. • For several problems the number of clusters in the K-means algorithm is unavailable. • Adaptive strategies enhance the performance of the K-means algorithm. • Parallel implementation is mandatory for large clustering problems. [ABSTRACT FROM AUTHOR]

We have developed biocatalytic methods for the stereoselective reduction of cyclic prochiral 1,3-diketones for the production of optically active β-hydroxyketones and/or 1,3-diols. The recombinant ketoreductase KRED1-Pglu (formulated as purified catalyst) and whole cells of wild type Escherichia coli DE3 Star were used as biocatalysts, displaying different and sometimes complementary stereoselectivity, thus allowing the preparation of stereochemically pure β-hydroxyketones (12–66% isolated yields, > 99% e.e.) and 1,3-diols (40–60% isolated yields, > 99% e.e.). [ABSTRACT FROM AUTHOR]

Mycelium‐bound lipase(s) from Aspergillus oryzae catalysed direct esterification of isoamyl alcohol and cinnamyl alcohol with acetic acid in organic solvent, showing high stability towards substrates and products. Water produced during the esterification did not significantly affect the equilibrium of the reaction, allowing for high conversions. These features were exploited for preparing flavour‐active acetate esters (isoamyl and cinnamyl acetate) in batch and continuous systems. A continuous stirred tank membrane reactor (CST‐MR) was developed securing good reactor productivity and high biocatalyst stability. [ABSTRACT FROM AUTHOR]

Preparation of optically-pure derivatives of 2-hydroxy-2-(3-hydroxyphenyl)-2-phenylacetic acid of general structure 2 was accomplished by enzymatic hydrolysis of the correspondent esters. A screening with commercial hydrolases using the methyl ester of 2-hydroxy-2-(3-hydroxyphenyl)-2-phenylacetic acid (1a) showed that crude pig liver esterase (PLE) was the only preparation with catalytic activity. Low enantioselectivity was observed with substrates 1a–d, whereas PLE-catalysed hydrolysis of 1e proceeded with good enantioselectivity (E = 28), after optimization. Enhancement of the enantioselectivity was obtained by chemical re-esterification of enantiomerically enriched 2e, followed by sequential enzymatic hydrolysis with PLE. The preparation of optically-pure (S)-2e was validated on multi-milligram scale. [ABSTRACT FROM AUTHOR]

When information and measures obtained from sequences of microscopic images are subject to time constraints, suitable fast algorithms must be implemented to process the whole data set. In this work, we deal with sequences of images obtained from time-lapse microscopy in order to detect single yeast cells in a microfluidics chip over time. The underlying idea consists in determining a minimum cost configuration for each couple of frames, which can be expressed by setting up and solving a linear programming (LP) problem. Laboratories seldom have the opportunity to use HPC hardware for such intent. For this reason, we propose an efficient GPU-parallel software implemented in CUDA and based on the simplex method, a common tool for solving LP problems. Our parallel strategy minimizes the threads divergence and maximizes the device occupancy, in order to maximize the overall throughput. Also, memory transfers between host and device have been minimized to exploit data locality. Experimental results on real images sequences highlight a promising speedup with respect to the CPU version suitable for real-time applications. [ABSTRACT FROM AUTHOR]

Microbial carboxylesterases are important biocatalysts that selectively hydrolyze an extensive range of esters. Here, we report the biochemical and structural characterization of an atypical carboxylesterase from Bacillus coagulans (BCE), endowed with high enantioselectivity toward different 1,2‐O‐isopropylideneglycerol (IPG or solketal) esters. BCE efficiently catalyzes the production of enantiopure (S)‐IPG, a chiral building block for the synthesis of β‐blockers, glycerophospholipids, and prostaglandins; efficient hydrolysis was observed up to 65 °C. To gain insight into the mechanistic bases of such enantioselectivity, we solved the crystal structures of BCE in apo‐ and glycerol‐bound forms at resolutions of 1.9 and 1.8 Å, respectively. In silico docking studies on the BCE structure confirmed that IPG esters with small acyl chains (≤ C6) were easily accommodated in the active site pocket, indicating that small conformational changes are necessary to accept longer substrates. Furthermore, docking studies suggested that enantioselectivity may be due to an improved stabilization of the tetrahedral reaction intermediate for the S‐enantiomer. Contrary to the above functional data implying nonlipolytic functions, BCE displays a lipase‐like 3D structure that hosts a “lid” domain capping the main entrance to the active site. In lipases the lid mediates catalysis through interfacial activation, a process that we did not observe for BCE. Overall, we present the functional‐structural properties of an atypical carboxyl esterase that has nonlipase‐like functions, yet possesses a lipase‐like 3D fold. Our data provide original enzymatic information in view of BCE applications as an inexpensive, efficient biocatalyst for the production of enantiopure (S)‐IPG. Database: Coordinates and structure factors have been deposited in the Protein Data Bank ( www.rcsb.org) under accession numbers 5O7G (apo‐BCE) and 5OLU (glycerol‐bound BCE) [ABSTRACT FROM AUTHOR]

The chemoenzymatic flow synthesis of enantiomerically pure captopril, a widely used antihypertensive drug, is accomplished starting from simple, inexpensive, and readily available reagents. The first step is a heterogeneous biocatalyzed regio- and stereoselective oxidation of cheap prochiral 2-methyl-1,3-propandiol, performed in flow using immobilized whole cells of Acetobacter aceti MIM 2000/28, thus avoiding the use of aggressive and environmentally harmful chemical oxidants. The isolation of the highly hydrophilic intermediate ( R)-3-hydroxy-2-methylpropanoic acid is achieved in-line by using a catch-and-release strategy. Then, three sequential high-throughput chemical steps lead to the isolation of captopril in only 75 min. In-line quenching and liquid-liquid separation enable breaks in the workflow and other manipulations to be avoided. [ABSTRACT FROM AUTHOR]

A robust two-enzyme system composed of an immobilized ketoreductase (KRED1-Pglu) and a glucose dehydrogenase ( Bm GDH) was developed via immobilization on aldehyde agarose for the stereoselective reduction of different ketones. The immobilized ketoreductase/glucose dehydrogenase system was continuously used in a flow reactor for weeks, even in the presence of concentrations of DMSO up to 20%. [ABSTRACT FROM AUTHOR]

The stereoselective desymmetrisation of achiral 2-alkyl-1,3-diols is performed by oxidation of one of the two enantiotopic primary alcohol moieties by means of Acetobacter aceti MIM 2000/28 to afford the corresponding chiral 2-hydroxymethyl alkanoic acids (up to 94 % ee). The procedure, carried out in aqueous medium under mild conditions of pH, temperature and pressure, contributes to enlarge the portfolio of enzymatic oxidations available to organic chemists for the development of sustainable manufacturing processes. [ABSTRACT FROM AUTHOR]

A high yielding bioprocess for 11-α hydroxylation of canrenone ( 1a ) using Aspergillus ochraceus ATCC 18500 was developed. The optimization of the biotransformation involved both fermentation (for achieving highly active mycelium of A. ochraceus ) and biotransformation with the aim to obtain 11-α hydroxylation with high selectivity and yield. A medium based on sucrose as C-source resulted particularly suitable for conversion of canrenone into the corresponding 11-hydroxy derivative, whereas the use of O 2 -enriched air and dimethyl sulfoxide (DMSO) as a co-solvent for increasing substrate solubility played a crucial role for obtaining high yields (>95%) of the desired product in high chemical purity starting from 30 mM (10.2 g/L) of substrate. The structure of the hydroxylated product was confirmed by a combination of two-dimensional NMR proton-proton correlation techniques. [ABSTRACT FROM AUTHOR]

The large consumption of freshwater in fermentations and bio-transformations is a matter of concern for the sustainability of many bio-processes. The use of seawater to perform bio-processes is a sustainable alternative. In this work, we used marine yeasts from deep-sub-seafloor sediments grown in seawater as bio-catalysts to perform the stereoselective reduction of different ketones, and the bio-transformations were accomplished in seawater as well. Strains of Meyerozyma guilliermondii and Rhodotorula mucilaginosa were able to reduce different aromatic ketones with high molar conversions and moderate-to-high enantioselectivity with no significant differences between bio-catalysis performed in seawater and freshwater. Finally, the selected marine yeasts were used for the reduction of key intermediates in seawater for the synthesis of molecules of pharmaceutical interest (desogestrel, norgestrel, gestodene, pramipexole). [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study concerns numerical studies and experimental validation of the mechanical behavior of hybrid specimens. These kinds of composite specimens are made up of thin carbon and glass substrates on which some Macro Fiber Composite® (MFC) piezoelectric patches are glued. A proper design and manufacturing of the hybrid specimens as well as testing activities have been performed. The research activity has been carried out under the FutureWings project, funded by the European Commission within the 7th Framework.Design/methodology/approach The paper describes the basic assumptions made to define specimen geometries and to carry out experimental tests. Finite element (FE) results and experimental data (laser technique measurements) have been compared: it shows very good agreement for the displacements’ distribution along the specimens.Findings Within the objectives of the project, the study of passive and active deformation characteristics of the hybrid composite material has provided reference technical data and has allowed for the correct adaptation of the FE models. More in particular, using the hybrid specimens, both the bending deformations and the torsion deformations have been studied.Practical implications The deformation capability of the hybrid specimens will be used in the development of prototypical three-dimensional structures, that, through the electrical control of the MFC patches, will be able to change the curvature of their cross section or will be able to change the angle of torsion along their longitudinal axis.Originality/value The design of nonstandard specimens and the tests executed represent a novelty in the field of structures using piezoelectric actuators. The numerical and experimental data of the present research constitute a small step forward in the field of smart materials technology. [ABSTRACT FROM AUTHOR]

A NADPH-dependent benzil reductase (KRED1-Pglu) was used as recombinant enzyme for catalysing the reduction of different functionalised ketones. The reactions were carried out in the presence of a catalytic amount of NADP + and an enzyme-coupled transformation (oxidation of glucose catalysed by glucose dehydrogenase), for regenerating the cofactor and thus driving the reaction to completion. KRED1-Pglu showed remarkable versatility, being able to reduce different β-ketonitriles and α-haloketones at different pHs; notably, depending on the nature of the substrate, KRED1-Pglu can be used for efficient and clean enzymatic reduction, avoiding side-reactions due to the pH of the medium. The reduction generally occurred with high enantioselectivity, allowing the preparation of enantiomerically enriched β-hydroxynitriles and halohydrins in high yields; the stereochemical outcome of the reduction followed in all the cases the so-called Prelog's rule. [ABSTRACT FROM AUTHOR]

Ethyl secodione ( 1) has been enantioselectively reduced by using different biocatalysts for the preparation of ethyl secol (13 R, 17 S)- 2a. The recombinant ketoreductase KRED1-Pglu converted the substrate with the highest reaction rate and stereoselectivity ( ee > 98 %), whereas whole cells of Pichia minuta CBS 1708 showed the highest productivity. Stereoselective reduction of 1 provides the key chiral precursor for the synthesis of a number of hormonal contraceptives (i.e., desogestrel, norgestrel, gestodene). [ABSTRACT FROM AUTHOR]

A new NADPH-dependent benzil reductase (KRED1-Pglu) was identified from the genome of the non-conventional yeast Pichia glucozyma CBS 5766 and overexpressed in E. coli. The new protein was characterised and reaction parameters were optimised for the enantioselective reduction of benzil to ( S)-benzoin. A thorough study of the substrate range of KRED1-Pglu was conducted; in contrast to most other known ketoreductases, KRED1-Pglu prefers space-demanding substrates, which are often converted with high stereoselectivity. A molecular modelling study was carried out for understanding the structural determinants involved in the stereorecognition experimentally observed and unpredictable on the basis of steric properties of the substrates. As a result, a new useful catalyst was identified, enabling the enantioselective preparation of different aromatic alcohols and hydroxyketones. [ABSTRACT FROM AUTHOR]

A sustainable and scalable process for the production of a new mixture of fructooligosaccharides (FOS) was developed using a continuous-flow approach based on an immobilized whole cells-packed bed reactor. The technological transfer from a classical batch system to an innovative flow environment allowed a significant improvement of the productivity. Moreover, the stability of this production system was ascertained by up to 7 days of continuous working. These results suggest the suitability of the proposed method for a large-scale production of the desired FOS mixture, in view of a foreseeable use as a novel prebiotic preparation. [ABSTRACT FROM AUTHOR]

Biocatalysis offers an alternative approach to conventional chemical processes for the production of single-isomer chiral drugs. Lipases are one of the most used enzymes in the synthesis of enantiomerically pure intermediates. The use of this type of enzyme is mainly due to the characteristics of their regio-, chemo- and enantioselectivity in the resolution process of racemates, without the use of cofactors. Moreover, this class of enzymes has generally excellent stability in the presence of organic solvents, facilitating the solubility of the organic substrate to be modified. Further improvements and new applications have been achieved in the syntheses of biologically active compounds catalyzed by lipases. This review critically reports and discusses examples from recent literature (2007 to mid-2015), concerning the synthesis of enantiomerically pure active pharmaceutical ingredients (APIs) and their intermediates in which the key step involves the action of a lipase. [ABSTRACT FROM AUTHOR]

• BCE thermodynamic stability decreases as the pH of the solution increases. • Aggregation of BCE is delayed as the pH of the solution increases. • BCE maintains an acceptable functionality over a wide range of pH conditions. • The temperature rise overwhelms the thermodynamic drawbacks as for BCE functionality. Microbial carboxylesterases are valuable biocatalysts that can selectively hydrolyze a wide spectrum of esters and may find their own applicability at industrial scale. In this work, we report the calorimetric study of an atypical enantioselective carboxylesterase from Bacillus coagulans (BCE). The influence of different pH conditions (from pH 6 to 9) on BCE thermal stability was investigated through Differential Scanning Calorimetry (DSC). A complete thermodynamic analysis of the system in combination with specific activity measurements was performed for the assessment of the best working conditions for such an enzyme. The overall results indicate that the kinetic benefits deriving from the temperature rise overwhelm the thermodynamic disadvantages in terms of protein stability, being aware that the working temperature should always be kept well below the onset of the denaturation process, which may trigger aggregation effects. Although the results concern this specific enzyme, the methodological approach has a general validity and may be useful as a guideline to design enzyme optimal working conditions through calorimetric methods [Display omitted] [ABSTRACT FROM AUTHOR]

Production of fructooligosaccharides (FOS) from sucrose was obtained using a bioprocess entirely performed in seawater. The halophilic fungus Cladosporium cladosporioides MUT 5506 was grown in a seawater-based medium and mycelium displayed an optimal activity in seawater at 50–60 °C, being stable up to 60 °C. Under optimized conditions in seawater (50 °C, sucrose 600 g/L, lyophilized mycelium 40 g/L), C. cladosporioides gave a maximum FOS yield of 344 g/L after 72 h with a preponderance of 1 F-FOS derivatives (1-kestose 184 g/L, 1-nystose 98 g/L and 1-fructofuranosylnystose 22 g/L), and the noteworthy presence of the non-conventional disaccharide blastose (30 g/L after 144 h). Lyophilized mycelium exhibited good stability in seawater (76% of the initial activity was retained after 15 cycles of reutilization). This proof-of-concept application reports for the first time the production of FOS in a non-conventional medium such as seawater. [ABSTRACT FROM AUTHOR]

Bimatoprost ( 1 ) and Latanoprost ( 2 ) are prostaglandin analogues widely used for glaucoma treatment. We have developed a new chemoenzymatic synthesis for 1 and 2 , which utilizes a highly stereoselective sequence of biotransformations catalyzed by enzymes belonging to a single microorganism (the yeast Pichia anomala ). The original synthesis, starting from (–)-Corey lactone benzoate (3a R ,4 R ,5 R ,6a S )- 3 , was modified by replacing three synthetic steps (C C reduction, stereoselective C O reduction and hydrolysis/deprotection of the benzoate ester) with a one-pot, three-enzymes reaction. The overall biotransformation gave good yields and it was highly stereoselective; noteworthy, by engineering the reaction medium, C C reduction could be modulated so that unsaturated (3a R ,4 R ,5 R ,6a S ,3′ S ) -6 or saturated intermediate (3a R ,4 R ,5 R ,6a S ,3′ R ) -7 could be preferentially obtained. [ABSTRACT FROM AUTHOR]

A biocatalyzed reduction of a prochiral bicyclic ketone afforded enantiomerically pure ( R )-2-acetylamino-6-hydroxy-4,5,6,7-tetrahydrobenzothiazole, a synthon of the anti-Parkinson ( S )-pramipexole and its ( R )-isomer, which is currently under investigation for the treatment of amyotrophic lateral sclerosis (ALS). [ABSTRACT FROM AUTHOR]

An easy and efficient one-pot methodology for the preparation of aldoximes combines the enzymatic oxidation of corresponding primary alcohols using different acetic acid bacteria and in situ condensation of the resulting aldehydes with hydroxylamine. [ABSTRACT FROM AUTHOR]