Current Trends in Pretreatment and Fractionation of Lignocellulose as Reflected in Industrial Patent Activities

The pretreatment process to disintegrate lignocellulose and to fractionate its three main components hemicellulose, cellulose, and lignin, is a crucial step to enable sustainable and economic value chains based on biomass feedstock. This review provides an overview of the recent patenting activities on pretreatment. Most of these activities focus on optimization of different known processes to improve economics, such as increased catalyst efficiency, effluents recirculation, or lignin valorization. However, also a number of patents and demonstration activities based on emerging concepts for pretreatments are observed.     

Solvent Influence on the Hydrodeoxygenation of Guaiacol over Pt/SiO2 and Pt/H‐MFI 90 Catalysts

Second generation biofuels are produced in the bioliq® process at the Karlsruhe Institute of Technology via gasification of pyrolysis oil and synthesis of gasoline from the emerging synthesis gas. An alternative strategy is the direct upgrading of the pyrolysis oil by hydrodeoxygenation (HDO). The present study reports on the HDO of guaiacol as one of the phenolic compounds strongly abundant in such mixtures. Special focus was laid on the solvent influence using Pt‐based catalysts. Higher HDO ability was seen using nonpolar solvents and acidic supports. Characterization of the catalysts before and after the test showed that the solvent did not only influence the reactivity, but also the catalyst stability.     

Novel Tacrine‐Grafted Ugi Adducts as Multipotent Anti‐Alzheimer Drugs: A Synthetic Renewal in Tacrine–Ferulic Acid Hybrids

Herein we describe the design, multicomponent synthesis, and biological, molecular modeling and ADMET studies, as well as in vitro PAMPA‐blood–brain barrier (BBB) analysis of new tacrine–ferulic acid hybrids (TFAHs). We identified (E)‐3‐(hydroxy‐3‐methoxyphenyl)‐N‐{8[(7‐methoxy‐1,2,3,4‐tetrahydroacridin‐9‐yl)amino]octyl}‐N‐[2‐(naphthalen‐2‐ylamino)2‐oxoethyl]acrylamide (TFAH 10 n ) as a particularly interesting multipotent compound that shows moderate and completely selective inhibition of human butyrylcholinesterase (IC₅₀=68.2 nM ), strong antioxidant activity (4.29 equiv trolox in an oxygen radical absorbance capacity (ORAC) assay), and good β‐amyloid (Aβ) anti‐aggregation properties (65.6 % at 1:1 ratio); moreover, it is able to permeate central nervous system (CNS) tissues, as determined by PAMPA‐BBB assay. Notably, even when tested at very high concentrations, TFAH 10 n easily surpasses the other TFAHs in hepatotoxicity profiling (59.4 % cell viability at 1000 μM ), affording good neuroprotection against toxic insults such as Aβ_1–40, Aβ_1–42, H₂O₂, and oligomycin A/rotenone on SH‐SY5Y cells, at 1 μM . The results reported herein support the development of new multipotent TFAH derivatives as potential drugs for the treatment of Alzheimer′s disease.     

Biochemical Characterization of Purified Esterase from Soybean (Glycine max) Seed

Alkaline esterase (carboxylic‐ester hydrolases; EC 3.1.1.1) extracted from germinated soybean seeds (Glycine max) was purified approximately 3.6 times by chromatography in a DEAE‐cellulose anion exchange column and filtration in Sephadex G100 gel. The molecular mass of the enzyme was estimated at 45 kDa by gel electrophoresis (SDS‐PAGE). The purified enzyme showed a specific activity of 5.6 U mg^?1 using p‐nitrophenyl butyrate as substrate. The esterase showed optimal activity at 47 °C in moderately alkaline pH, low stability in temperatures higher than 50 °C, and high stability at pH values between 6 and 9.5. The Ca²⁺ and Co²⁺ ions proved to have a positive effect on enzyme activity; however, Hg²⁺ completely inhibited esterase activity. Using p‐nitrophenyl butyrate as substrate, the enzyme showed a K_m of 0.39 mM, V_max of 31.5 mM mg^?1 min^?1 and k_cat 7.60 × 10⁶ s^?1. Regarding substrate affinity, the enzyme showed greater activity for substrates containing short‐chain fatty acids, especially p‐nitrophenyl acetate. Such characteristics give the enzyme great potential for application in the production of low molecular weight esters, in the food industry, and in chemical products. This enzyme is another new member of the family of lipases and esterases from vegetable seeds with high activity and stability in alkaline pH.     

Application of Cohesive Zone Modeling to Composite Bonded Repairs

Cohesive zone models can play an important role in the definition of repair strategies. These models allow the prediction of damage initiation and propagation. They are based on a softening relationship between stresses and relative displacements between crack faces, thus simulating a gradual degradation of material properties. Typically, stress-based and energetic fracture mechanics criteria are used to simulate damage initiation and growth, respectively. Those elements are placed at the planes where damage is prone to occur which, in the case of bonded repairs, is usually easy to identify a priori. Taking this into consideration, cohesive mixed-mode damage models based on interface finite elements were used with the objective of optimizing the repair efficiency. The determination of the cohesive pure mode softening laws is a key aspect of these models, and the direct method is the most accurate process to do it. The models were validated and applied to two different cases involving repairs. Several geometrical aspects influencing the single-strap repair strength were analyzed as well as the evolution of the maximum load and alteration of damage mechanism as a function of the angle used in scarf joints. It was verified that CZM are able to predict with accuracy the damage mechanisms and strength of composite bonded repairs, thus constituting a powerful tool in its design.     

Correlation Between Chemical Composition and Adherence of Cr and Co Coatings Deposited by Electric Arc

This paper presents the adhesive strength of FeCr and FeCoCr coatings produced by electric arc thermal spray process on carbon steel plates. Carbon steels are not resistant to corrosion and several methods are used in surface engineering to protect them from aggressive environments such as the marine one. The main objective of this work is the evaluation of the mechanical and metallurgical properties of coatings produced by thermal spray on carbon steel. Five chemical compositions were tested in order to give a large panel of possibility. Coatings were characterized by several methods to result in a screening of performance. The physical properties of coatings were also evaluated by adhesion quantification, using pull-off test, and microhardness measurement. The assessment of microstructural morphology by X-ray diffraction (XRD) and scanning electron microscopy (SEM) was made. The open circuit potential was monitored to evaluate the corrosion tendency. SEM results showed uniformity in the deposited layer and low amount of oxide and porosity. The adhesive strength of FeCoCr alloy coatings was higher than other coating conditions. In the immersion test, all sealed conditions presented high corrosion potential. Semi-quantitative phase calculation was performed by the Rietveld method using XRD. The presence of FeCr, FeCo, and austenite phases was determined. Based on the performed characterizations, the findings suggested that the FeCrCo deposition, with an epoxy sealing, is suitable to be used as an efficient coating of carbon steel in aggressive corrosive environments.     

Soft X‐ray Ptychographic Imaging and Morphological Quantification of Calcium Silicate Hydrates (C–S–H)

Morphological details of calcium silicate hydrate (C–S–H) stemming from the hydration process of Portland cement (PC) phases are crucial for understanding the PC‐based systems but are still only partially known. Here we introduce the first soft X‐ray ptychographic imaging of tricalcium silicate (C₃S) hydration products. The results are compared using both scanning transmission X‐ray and electron transmission microscopy data. The evidence shows that ptychography is a powerful method to visualize the details of outer and inner product C–S–H of fully hydrated C₃S, which have fibrillar and an interglobular structure with average void sizes of 20 nm, respectively. The high‐resolution ptychrography image enables us to perform morphological quantification of C–S–H, and, for the first time, to possibly distinguish the contributions of inner and outer product C–S–H to the small angle scattering of cement paste. The results indicate that the outer product C–S–H is mainly responsible for the q^?3 regime, whereas the inner product C–S–H transitions to a q^?2 regime. Various hypotheses are discussed to explain these regimes.     

Constituents and Pharmacological Activities of Myrcia (Myrtaceae): A Review of an Aromatic and Medicinal Group of Plants

Myrcia is one of the largest genera of the economically important family Myrtaceae. Some of the species are used in folk medicine, such as a group known as “pedra-hume-caá” or “pedra-ume-caá” or “insulina vegetal” (insulin plant) that it is used for the treatment of diabetes. The species are an important source of essential oils, and most of the chemical studies on Myrcia describe the chemical composition of the essential oils, in which mono- and sesquiterpenes are predominant. The non-volatile compounds isolated from Myrcia are usually flavonoids, tannins, acetophenone derivatives and triterpenes. Anti-inflammatory, antinociceptive, antioxidant, antimicrobial activities have been described to Myrcia essential oils, while hypoglycemic, anti-hemorrhagic and antioxidant activities were attributed to the extracts. Flavonoid glucosides and acetophenone derivatives showed aldose reductase and α-glucosidase inhibition, and could explain the traditional use of Myrcia species to treat diabetes. Antimicrobial and anti-inflammatory are some of the activities observed for other isolated compounds from Myrcia.     

Recent Advances in Lipase-Mediated Preparation of Pharmaceuticals and Their Intermediates

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.