Class Of Oxidoreductases Research Articles

Chronic and Periodic Effects of Smoke from Crop Residue Combustion on Soil Enzymatic Activity

Wildfires lead to the emission of large volumes of toxic smoke, which is transported hundreds of kilometres away from the fires and can have a negative impact on soil, biota and humans. A series of modelling experiments on pyrogenic fumigation of soil were carried out to assess the effects of gaseous products from wildfires on soil biochemical parameters. The effects of chronic exposure to gaseous substances and periodic, repetitive effects of smoke exposure on soil were determined. The results were compared with a single intensive smoke exposure. It was found that pyrogenic impact significantly affected the change of enzymatic activity of ordinary chernozem. The degree of influence depended on the duration and periodicity of smoke exposure. In all experiments enzymes of oxidoreductase class (catalase, peroxidase, polyphenol oxidase) were more sensitive to fumigation than invertase from hydrolase class. The reason of suppression of enzymatic activity of soils is high concentrations of toxic gases. The following concentrations exceeded the maximum permissible concentrations for atmospheric air: CO 714 times, phenol (hydroxybenzene) 441 times, acetaldehyde 24100 times, formaldehyde 190 times. Accumulation of polycyclic aromatic hydrocarbons (PAHs) in soil after fumigation was revealed, the total content of PAHs was 377 ng/g. The highest values were recorded for naphthalene, where the concentration was 4.4 times higher than the maximum permissible and phenanthrene 2.8 times higher than the maximum permissible. It was found that 60-minute intensive smoke affects the soil to a lesser extent than chronic and periodic. Indicators of enzymatic activity of chernozem after such fumigation decreased by 15-33% depending on the enzyme, in chronic and periodic by 41-84 and 31-78%, respectively. The obtained data indicate a significant effect of smoke on enzymatic activity of soils under chronic and periodic exposure to gaseous products of combustion.

Unveiling the potential of novel 5α-reductase inhibitors via ligand based drug design, molecular docking and ADME predictions to manage BPH

Benign prostatic hyperplasia (BPH), a prevalent condition among elderly males characterized by the non-cancerous enlargement of the prostate gland is due to the increased stromal and epithelial cell numbers. The enlargement is driven by an active dihydrotestosterone (DHT), synthesized from its prohormone testosterone under the catalytic effect of 5α-reductase Type-II (5-AR2) enzyme. To reduce the increased DHT levels and ultimately to control prostate growth, inhibition of the 5-AR represent an interesting therapeutic target. The 3D crystallography structure 5-AR2, a member of the steroid 5-AR family belonging to the class of oxidoreductase has been resolved recently and opened the door to develop selective novel inhibitors of 5-AR Type-II isoform using molecular modeling techniques. The Force field and Gaussian-field three-dimensional quantitative structure–activity relationship (3D-QSAR) models have been developed using 42 selective 5-AR2 inhibitors belonging to chemical class of steroidal androstene. Partial least squares analysis produced statistically significant model with R2training = 0.9367, 0.9459 and predictability Q2test = 0.7233, 0.8595. Developed 3D-QSAR model include steric, electrostatic, hydrophobic, and hydrogen bond acceptor and donor field indicators, whereas the potential field contributions indicated the importance of steric feature in governing their biological activity. Protein-ligand interaction pattern analysis revealed that amino acid residues GLU57, ARG114, TYR91 present in the active site of 5-AR2 are crucial for lower energy complexes with good binding affinity. Identified hits were finally adjudged for their druggability by determining in-silico pharmacokinetic parameters. Further, RMSD, binding free energy calculations and post MD analysis demonstrated the enhanced binding affinity with better ΔGbind value (-79.6 ± 3.9 kcal/mol) of identified ligand A-10 than the reference molecule finasteride (-69.13 ± 4.69 kcal/mol). Combined approach of ligand-based and structure-based models have provided an improved understanding of the structural properties of androstene class that may be further used to develop novel 5-AR2 inhibitors to be useful in BPH.

Impact of surface-active ionic solutions on the structure and function of laccase from trametes versicolor: Insights from molecular dynamics simulations

Many protein-ionic liquid investigations have examined laccase interactions. Laccases are a class of poly-copper oxidoreductases that retain significant biotechnological relevance owing to their notable oxidative capabilities and their application in the elimination of synthetic dyes, phenolic compounds, insecticides, and various other substances. This study investigates the impact of surface active ionic liquids (SAILs), namely, decyltrimethylammonium bromide [N10111][Br] and 1-decyl-3-methylimidazolium chloride [C10mim][Cl] as cationic surfactant ionic liquids and cholinium decanoate [Chl][Dec], an anionic surfactant ionic liquid, on the structure and function of laccase from the fungus Trametes versicolor (TvL) by the molecular dynamics (MD) simulation method. In summary, this study showed that laccase solvent-accessible surface area increased in the ionic liquid [Chl][Dec] while it decreased in the other two ionic liquids. Interestingly, [Chl][Dec] ionic liquid components formed hydrogen bonds with laccase, while [N10111][Br] and [C10mim][Cl] components were unable to form hydrogen bonds with laccase. The quantity of hydrogen bonds formed between water molecules and the enzyme was also diminished in the presence of [Chl][Dec] in comparison to the other two ionic liquids. especially at a concentration of 250 mM. In 250 mM concentrations of [N10111][Br] and [C10mim][Cl], clusters of long-chain cations are likely to form near the copper T1 site. However, even at low [Chl][Dec] concentrations, long [Dec]- chains were observed to penetrate the enzyme near the copper T1 site, and at 250 mM [Chl][Dec], a large cluster of anions occupied the opening of the active site. The results of the analysis also show that the interaction between the [Dec]- anion and the enzyme is stronger than the interaction between [N10111]+ and [C10mim]+ with laccase; in addition, the [Dec]- anion, compared to [Br]- and [Cl]- has a much greater tendency to bind with the enzyme residues.

Understanding the initial events of the oxidative damage and protection mechanisms of the AA9 lytic polysaccharide monooxygenase family.

Lytic polysaccharide monooxygenase (LPMO) is a new class of oxidoreductases that boosts polysaccharide degradation employing a copper active site. This boost may facilitate the cost-efficient production of biofuels and high-value chemicals from polysaccharides such as lignocellulose. Unfortunately, self-oxidation of the active site inactivates LPMOs. Other oxidoreductases employ hole-hopping mechanisms as protection against oxidative damage, but little is generally known about the details of these mechanisms. Herein, we employ highly accurate theoretical models based on density functional theory (DFT) molecular mechanics (MM) hybrids to understand the initial steps in LPMOs' protective measures against self-oxidation; we identify several intermediates recently proposed from experiment, and quantify which are important for protective hole-hopping pathways. Investigations on two different LPMOs show consistently that a tyrosine residue close to copper is crucial for protection: this explains recent experiments, showing that LPMOs without this tyrosine are more susceptible to self-oxidation.

Microbial alcohol dehydrogenases: recent developments and applications in asymmetric synthesis.

Alcohol dehydrogenases are a well-known group of enzymes in the class of oxidoreductases that use electron transfer cofactors such as NAD(P)+/NAD(P)H for oxidation or reduction reactions of alcohols or carbonyl compounds respectively. These enzymes are utilized mainly as purified enzymes and offer some advantages in terms of green chemistry. They are environmentally friendly and a sustainable alternative to traditional chemical synthesis of bulk and fine chemicals. Industry has implemented several whole-cell biocatalytic processes to synthesize pharmaceutically active ingredients by exploring the high selectivity of enzymes. Unlike the whole cell system where cofactor regeneration is well conserved within the cellular environment, purified enzymes require additional cofactors or a cofactor recycling system in the reaction, even though cleaner reactions can be carried out with fewer downstream work-up problems. The challenge of producing purified enzymes in large quantities has been solved in large part by the use of recombinant enzymes. Most importantly, recombinant enzymes find applications in many cascade biotransformations to produce several important chiral precursors. Inevitably, several dehydrogenases were engineered as mere recombinant enzymes could not meet the industrial requirements for substrate and stereoselectivity. In recent years, a significant number of engineered alcohol dehydrogenases have been employed in asymmetric synthesis in industry. In a parallel development, several enzymatic and non-enzymatic methods have been established for regenerating expensive cofactors (NAD+/NADP+) to make the overall enzymatic process more efficient and economically viable. In this review article, recent developments and applications of microbial alcohol dehydrogenases are summarized by emphasizing notable examples.

Пероксидазы бактерий в биоремедиации

As a result of the work of industrial enterprises, agricultural production and other types of human activity in the world, the problem of environmental pollution with difficult-to-degrade toxic compounds is becoming increasingly acute. Various physical and chemical methods of recultivation and remediation have serious limitations, such as high cost, labor intensity, as well as disruption of the ecological-trophic structure and successional changes in ecosystems. The catalytic decomposition of pollutants using enzymes can compete with classical methods of cleaning the environment from pollutants. Peroxidases are widespread enzymes belonging to the class of oxidoreductases that can destroy the carbon backbone of complex organic compounds. This review presents recent research on the application of bacterial peroxidases as environmentally friendly catalysts for the bioremediation of contaminated ecosystems.

Soil salinity effects on hydrolase and oxidoreductase class enzymes

This article presents information on the effect of salinity types and levels on the activity of urease, protease enzymes, oxidoreductases, catalase, and dehydrogenase enzymes, among the main enzymes in the irrigated alluvial habitats of the Bukhara region with varying degrees of salinity. One of the main indicators affecting the enzymatic activity of the soil is the salinity level. Enzymatic activity of non-saline soils, weakly saline, moderately saline, and strongly saline soils were analyzed in this article.

Oxidoreductase activity of soybeen seedlings at the early stage of ontogenesis

The results of analysis of specific activity and multiple forms of oxidoreductase class enzymes are presented: antioxidant complex (catalase and peroxidase) and dehydrogenases (alcohol dehydrogenase, NAD+-malate dehydrogenase, glucose-6-phosphate dehydrogenase). Seven varieties of soybean (Glycine max (L.) Merrill) served as the object of the study. Dormant seeds and 3- and 7-day-old soybean seedlings were used for the analysis. Protein content was determined by the Lowry method, peroxidase activity was determined by colorimetric, catalase and the studied dehydrogenases – by spectrophotometric methods, electrophoretic spectra of enzymes – by electrophoresis on 7.5% polyacrylamide gel columns. Identification of the zones with enzymatic activity on the gel was performed by appropriate histochemical methods. Analysis of specific activity of antioxidant enzymes in dormant soybean seeds revealed increased activity of peroxidase and low activity of catalase. During seed germination, the inverse relationship of the specific activity of these enzymes is observed. On the 7th day the specific activity of catalase increases, that of peroxidase decreases to a minimum. In soybean germination, 5 forms of catalase were detected, indicating low polymorphism and stability of the enzyme, and 18 forms of peroxidase, which confirm high polymorphism and the possibility of using this enzyme as a marker of biochemical processes. Alcohol dehydrogenase and glucose-6-phosphate dehydrogenase were found to be of low heterogeneity, with the specific activity of these enzymes decreasing during germination compared to the dormant period of soybean seeds. The specific activity of NAD+-malate dehydrogenase increases slightly during germination. Eight forms of this enzyme were detected in the soybean varieties studied indicating increased polymorphism. In dormant soybean seeds, the electrophoretic spectra of NAD+-malate dehydrogenase exhibited varietal diversity allowing the enzyme to be used as a marker for further studies.

Green “one-pot” fluorescent bis-indolizine synthesis with whole-cell plant biocatalysis

Abstract An efficient one-pot route leading to bis-indolizine symmetric compounds has been developed via a new approach from the dipyridinium heterocyclic compound, reactive halogenated derivative, and activated alkyne through biocatalysis. A set of local plants was evaluated for its catalytic potential in “one-pot” biocatalysis of these valuable fluorescent compound synthesis reactions. Most of these biocatalysts containing enzymes from the oxidoreductase class (peroxidase: 0.56–1.08 mmol purpurogallin‧g−1 fresh weight‧min−1, polyphenol oxidase (PPO) : 27.19–48.95 PPO units‧mg tissue−1, CAT: 3.27–21.71 µmol O2‧g−1 fresh weight‧min−1), were used as green catalysts in the multi-component cycloaddition reaction, in an aqueous buffer solution, for the production of bis-indolizine compounds in moderate to excellent yields (45–85%). The horseradish root (Armoracia rusticana) has been selected as the most promising biocatalyst source among the evaluated plants, and the obtained yields were greater than in the conventional synthesis method. The structures of indolizine derivatives were confirmed by nuclear magnetic resonance spectra, elemental analyses, as well as Fourier transform-infrared spectra. The cytotoxicity of the latter obtained indolizine compounds on the growth of the model microorganism, Saccharomyces cerevisiae MIUG 3.6 yeast strain, was also evaluated. Various parameters (number of generations, growth rate, generation time, dry matter yield, the degree of the budding yeast cells, and the degree of yeast autolysis, fermentation intensity), which describe the yeast growth, suggest that the nutrient broth supplemented with different concentrations of bis-indolizine compounds (10 and 1 µM) had no toxic effect on the yeast strain growth, under submerged cultivation conditions.

Smoke toxicity to the biota and the biological activity of soils when modeling fires

The paper presents the results of our study on the effect of one type of pyrogenic factor (smoke) after burning coniferous wood chips on several bioindicators (soil enzymes, microorganisms, mesofauna, plants of agricultural crops). Exposition to smoke for 60 minutes was found to significantly affect the enzymatic activity of common chernozem. Fumigation caused a decrease in such enzymes as catalase, peroxidase, polyphenol oxidase and invertase. The enzymes of the oxidoreductase class were the most sensitive to smoke. High toxicity of gaseous combustion products to the soil flora and fauna was revealed. The acute toxicity of smoke to the bioindicators was determined as a result of fumigation. High mortality of test objects (Eisenia fetida, Nauphoeta cinerea) was recorded in our experiments. Soil microorganisms (Azotobacter chroococcum and Penicillium chrysogenum) proved to be informative after 30–120 minutes of fumigation. Resistance of plant sprouts (Raphanus sativus, Triticum aestivum, and Pisum sativum) to combustion gaseous products was revealed. An experiment to analyze the chemical composition of gases in smoke was performed. Such hazardous compounds as sulphur dioxide (SO2), nitrogen oxide and dioxide (NO, NO2), carbon monoxide (CO), acetaldehyde (C2H4O), formaldehyde (CH2O), phenol (C6H6O) hydroxybenzene and others were found to be contained therein. Our analysis revealed that the concentrations of carbon monoxide were 714 times higher than its maximum permissible concentration (MPC), which acetaldehyde was 24,100 times higher. The nitrogen oxide and nitrogen dioxide concentrations were 100 and 300 times higher, respectively.

Assessment of Changes in the Biological Activity of Mountain Meadow-Steppe Soils of Pastures of Different Stages of Digression in the Central Caucasus

The indicators of biological activity (humus content and reserves, microbial biomass carbon content and reserves, activity of hydrolase and oxidoreductase class enzymes) in the upper horizons (0–10 cm) of mountain meadow-steppe soils of the Central Caucasus (Kabardino-Balkaria) were determined at different stages of pasture digression (D1, D2, D3). It was found that the values of controlled soil parameters in conditions of weakly (D1) and moderately disturbed (D2) meadow phytocenoses did not significantly differ (t 1.97; P 0.05). Statistically significant decreases (t 2.95; P 0.05) in biological parameters were revealed in soils of severely disturbed meadow steppes (D3) compared with less damaged meadows (D1 and D2). Based on the totality of the studied indicators of biological activity, an integral indicator of the ecological and biological state of soils (IIEBSS) is calculated, reflecting the overall level of biological activity of the studied soils at different stages of digression of meadow-steppe communities. There was a decrease in the IIEBSS of moderately grazed (D2) and overgrazed (D3) meadows relative to the values of the conditional standard (D1) by 11and 45%, respectively. The obtained results of the biological state of mountain meadow-steppe soils are used for monitoring studies aimed at assessing the degree of change in the soil and vegetation cover of mountain pasture ecosystems.

Lignocellulolytic Microbial Systems and its Importance in Dye Decolourization: A Review

Effluents containing dyes from different industrial sectors pose a serious threat to the environment. Different physicochemical strategies are being carried out in industry to reduce the toxicity of dye-containing waste so that dye-mixed wastewater can be further utilized in agriculture or irrigation purposes in water-scarce areas. But those techniques are economically not feasible. There is an alternative mechanism present in biological systems that are biocatalysts which is eco-friendly, low cost, and sustainable. Lignin peroxidase, Laccase, Manganese peroxidase are oxidoreductase classes of enzymes with the ligninolytic ability and are potential biocatalysts for the degradation of environmental toxicants like dyes. Besides ligninolytic enzymes, cellulase, pectinase are also powerful candidates for dye decolourization. Most interestingly these biocatalysts are found in a variety of microbial monoculture as well as in mixed microbial consortia. The consortia are able to reduce the organic load of dye-containing industrial effluent at a higher rate rather than the monoculture. This article critically reviews the efficacy of lignocellulolytic enzymes in dye decolourization by both monoculture and consortia approaches. In addition, this review discusses the genetically and metabolically engineered microbial systems that contribute to dye decolourization as well as put forward some future approaches for the enhancement of dye removal efficacy.

Dimension-driven cobalt porphyrin nanoframework mimics dehydrogenase activity for inhibition of cancer proliferation

Dehydrogenases are a class of oxidoreductases that catalyze a wide variety of oxidative reactions in living organisms to maintain the redox homeostasis. Developing materials with dehydrogenase activity to break the homeostasis for the treatment of diseases with immortal proliferative properties has broad application prospects. Here, we use porphyrin ligands with good biocompatibility, and Co metal centers with high catalytic activity to jointly construct various dimensional Co porphyrin nano-coordination frameworks, and mimicking their catalytic performance of dehydrogenase activity. The results show that the one-dimensional nanoframeworks have the best dehydrogenase-like catalytic oxidation efficiency. At the same time, the cobalt porphyrin nanoframeworks with dehydrogenase-like activity inhibit cancer proliferation effectively.

Activity‐Based Protein Profiling of Oxidases and Reductases

AbstractActivity‐based protein profiling (ABPP) as a proteomic tool allows measuring the activity of enzyme classes or distinct proteins in their cellular context, annotating the function of uncharacterized proteins, and investigating the target profile of small molecule inhibitors. While hydrolases and other enzyme classes, which exhibit a characteristic nucleophilic residue, can be addressed by electrophilic activity‐based probes, the large enzyme class of oxidoreductases has received much less attention in ABPP. In this review the state of the art of ABPP of oxidases is presented. The most frequent principle in ABPP for oxidases is the oxidative activation of the ABPP probe leading to an electrophilic group as exemplified for alkyne or amine based warheads. Alternatively, in rare cases ABPP probes can address characteristic electrophilic or nucleophilic residues of certain oxidases. Most recently, with NQO2 the first example of ABPP for a reductase has been reported.

Influence of terms and methods of storage on changes in enzyme activity of meadow chernozem-like soil on Zeya-Bureya plain

The analysis of the biological and enzymatic properties of soils is an important aspect of soil ecology, but the results of studies can be strongly influenced by the storage conditions of the samples. Variation in storage methods and duration studies reduces the ability to accurately interpret data and compare results. This work presents a study of the influence of various storage conditions and time on the results of the activity of enzymes of hydrolase class (urease, phosphatase), and oxidoreductases class (catalase, peroxidase and polyphenoloxidase) of meadow chernozem-like soil of the Zeya-Bureya plain. For the research, a laboratory experiment was performed, in which naturally moist and air-dry samples were taken and stored under various conditions: room temperature (+23 – +25 °С), low positive temperature (refrigerator, +10 °C), negative temperature (freezer, –10 °С) within 7, 28, 90 and 365 days. As a result, we found that drying soil samples immediately after sampling increases the activity of urease, phosphatase, peroxidase and polyphenoloxidase. Storage conditions do not significantly affect the activity of enzymes. To assess the actual enzymatic activity, we recommend using naturally moist soil samples immediatel y after sampling; to assess potential enzymatic activity, drying the soil and storing it for no more than 7 days are recommended. The results of this study provide useful information on the impact of sample storage conditions for researchers of enzyme activity in similar climates and contribute to further consideration and discussion of the implications of sample storage.

Cell-wall microdomain remodeling controls crucial developmental processes.

Plant cell walls display cellular and subcellular specificities. At the subcellular level, wall regional territories with specific compositions are necessary for macroscopic developmental processes. These regional specificities were named differently throughout the years, and are unified here under the term 'cell-wall microdomains' that define the local composition and organization of wall polymers underlying territories of wall loosening and/or softening or stiffening. We review the occurrence and developmental role of wall microdomains in different cell types. We primarily focus on the contribution of two categories of wall-remodeling molecular actors: fine-tuning of homogalacturonan (HG; pectin) demethylesterification patterns and two classes of oxidoreductases [class III peroxidases (CIII PRXs) and laccases (LACs)], but we also highlight two different molecular scaffolds recently identified for positioning specific CIII PRXs.

INFLUENCE OF OIL POLLUTION ON ACTIVITY OF SOIL ENZYMES OF OXIDOREDUCTASE AND HYDROLASE CLASSES

Soil enzymatic activity is the most important biochemical parameter of soil fertility and it is determined by chemical composition, species and quantitative diversity of soil microbiota and plants, and the set and degree of activity of soil enzymes. The article shows the dynamics of enzymatic activity of the soil contaminated with oil from Vishenskoyedeposit in Melekesskiy district of Ulyanovsk region before and after spring wheatcultivation, as well as using biohumus, zeolite and diatomite sorbents. To assess the biological state of the soil contaminated with oil products, the activity of the main enzymes of the soil pool of the class of oxidoreductases (polyphenol oxidase), peroxidase, catalase) and the class of hydrolases (phosphatase, invertase) was determined. As a result of the studies, it was found that oil pollution reduces activity of oxidoreductase and part of hydrolytic enzymes. The inhibitiondegree correlates with oilconcentration in the soil. A direct dependence of inhibitiondegree of polyphenol oxidase, catalase, phosphatase and invertase on oil concentration was found. It was found that introduction of diatomite increased the activity of peroxidase and invertase, zeolite and biohumus - phosphatase. To assess the state of soil fertility, humus accumulation coefficient (humification coefficient) is used, which is defined as the ratio of polyphenol oxidase activity to peroxidase activity. This coefficient allowsto assess the tendencies of humus formation processes: humification or mineralization. It was determined that the introduction of low doses of oil (2-3%) increases humification coefficient, and high concentrations (8%) reduce it. To diagnose the state of oil-contaminated soils, it is recommended to determine the activity of basic enzymes: polyphenol oxidase, peroxidase, catalase, phosphatase, and invertase.

Enzymes as Potencial Source for Clean Label Bakery Product: Part 1, Mechanism and Application Single Enzym

Background: Increased public awareness of consuming healthy food has driven bakery industry to applied production methods and components of food products that are tailored to the market needs. Food product can be positioned as natural, organic, or free from additives/ preservatives which often referred to clean label trend. Bakery industry commonly using chemical emulsifier as component which improve characteristic and quality baked goods. Usage of chemical component is not appropriate with perception of clean label, although it is not yet clear what a clean label exactly means. Chemical emulsifier has potentially negative effect to health such as intestinal inflammation, obesity, metabolic syndrome and glucose resistance based on several research. Food enzyme can be alternative to replace chemical emulsifier and potentially source of clean label bakery product. Therefore, sustainable study was needed to find role single enzym as food additive and processing aid in bakery product application.Scope and approach: This review explain about the role single enzyme application in bakery product which discuss under three main headings include (i) enzyme as food additive and processing aid, ii) Characteristic enzyme to improve bakery product processing (dough mixing, fermentation, baking), sensories properties and appearance iii) Enzyme mechanism and application to enhance bakery product quality. Optimization of the role and function of enzymes can be conduct by enzyme quality validation through baking tests including formulation development, process parameters (dough rheology, handling machine and baking parameter), product appearance and sensory characteristics.Key findings and conclusion: Food enzymes play a role in enzymatic modifications as biodegradable proteins which not affected to nutritional value baked goods. Enzyme technology is a clean process with low energy consumption, low waste production, safe and less toxic working environment. Therefore, enzyme has potential to fulfill clean label trends and encourage researchers and developers in food industry to explore potential use of food enzymes in bakery products. Enzymes which usually used in bakery come from hydrolase class (amylase, protease, hemicellulase, lipase, xylanase and asparaginase), oxidoreductase class (lipoxygenase and glucose oxidase) and transferase class (transglutaminase). Application enzymes in bakery processs have their respective roles according to enzymes specific characteristics. Enzymes has the main role such as improve rheological and functional properties of dough according to baked goods type, enhance quality and characteristics baked goods including volume, crumb texture, color, taste and extend shelf life (antistaling). Sustainable research and development was needed to optimize the role of enzyme in baked goods by several approach such as (i) incorporation enzymes with other ingredients in the food matrix, (ii) parameters which affect to the work of enzymes in food systems (iii) potential of enzyme combinations to improve baked goods quality and (iv) understanding of usage regulation enzymes as food additives and food processing. Keyword: enzyme, clean label, food additive, processing aid, bakery product

Immobilization of Lathyrus cicera Amine Oxidase on Magnetic Microparticles for Biocatalytic Applications.

Amine oxidases are enzymes belonging to the class of oxidoreductases that are widespread, from bacteria to humans. The amine oxidase from Lathyrus cicera has recently appeared in the landscape of biocatalysis, showing good potential in the green synthesis of aldehydes. This enzyme catalyzes the oxidative deamination of a wide range of primary amines into the corresponding aldehydes but its use as a biocatalyst is challenging due to the possible inactivation that might occur at high product concentrations. Here, we show that the enzyme’s performance can be greatly improved by immobilization on solid supports. The best results are achieved using amino-functionalized magnetic microparticles: the immobilized enzyme retains its activity, greatly improves its thermostability (4 h at 75 °C), and can be recycled up to 8 times with a set of aromatic ethylamines. After the last reaction cycle, the overall conversion is about 90% for all tested substrates, with an aldehyde production ranging between 100 and 270 mg depending on the substrate used. As a proof concept, one of the aldehydes thus produced was successfully used for the biomimetic synthesis of a non-natural benzylisoquinoline alkaloid.

3D-QSAR and scaffold hopping based designing of benzo[d]ox-azol-2(3H)-one and 2-oxazolo[4,5-b]pyridin-2(3H)-one derivatives as selective aldehyde dehydrogenase 1A1 inhibitors: Synthesis and biological evaluation.

Aldehyde dehydrogenase 1 (ALDH1A1), an oxidoreductase class of enzymes, is overexpressed in various types of cancer cell lines and is the major cause of resistance to the Food and Drug Administration (FDA)-approved drug, cyclophosphamide (CP). In cancer conditions, CP undergoes a sequence of biotransformations to form an active metabolite, aldophosphamide, which further biotransforms to its putative cytotoxic metabolite, phosphoramide mustard. However, in resistant cancer conditions, aldophosphamide is converted into its inactive metabolite, carboxyphosphamide, via oxidation with ALDH1A1. Herein, to address the issue of ALDH1A1 mediated CP resistance, we report a series of benzo[d]oxazol-2(3H)-one and 2-oxazolo[4,5-b]pyridin-2(3H)-one derivatives as selective ALDH1A1 inhibitors. These inhibitors were designed using a validated 3D-quantitative structure activity relationship (3D-QSAR) model coupled with scaffold hopping. The 3D-QSAR model was developed using reported indole-2,3-diones based ALDH1A1 inhibitors, which provided field points in terms of electrostatic, van der Waals and hydrophobic potentials required for selectively inhibiting ALDH1A1. The most selective indole-2,3-diones-based compound, that is, cmp 3, was further considered for scaffold hopping. Two top-ranked bioisosteres, that is, benzo[d]oxazol-2(3H)-one and 2-oxazolo[4,5-b]pyridin-2(3H)-one, were selected for designing new inhibitors by considering the field pattern of 3D-QSAR. All designed molecules were mapped perfectly on the 3D-QSAR model and found to be predictive with good inhibitory potency (pIC50 range: 7.5-6.8). Molecular docking was carried out for each designed molecule to identify key interactions that are required for ALDH1A1 inhibition and to authenticate the 3D-QSAR result. The top five inhibitor-ALDH1A1 complexes were also submitted for molecular dynamics simulations to access their stability. In vitro enzyme assays of 21 compounds suggested that these compounds are selective towardALDH1A1 over the other two isoforms, that is,ALDH2 and ALDH3A1. All the compounds were found to be at least three and two times more selective towardALDH1A1 over ALDH2 and ALDH3A1, respectively. All the compounds showed an IC50 value in the range of 0.02-0.80 μM, which indicates the potential for these to be developed as adjuvant therapy for CP resistance.