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Phasin (PhaP), one of the polyhydroxyalkanoate granule-associated protein, enhances cell growth and polyhydroxybutyrate (PHB) biosynthesis by regulating the number and size of PHB granules. However, few studies have applied phasins to various PHB production conditions. In this study, we identified novel phasin genes from the genomic data of Arctic soil bacterium Pseudomonas sp. B14-6 and determined the role of phaP1Ps under different PHB production conditions. Transmission electron microscopy and gel permeation chromatography revealed small PHB granules with high-molecular weight, while differential scanning calorimetry showed that the extracted PHB films had similar thermal properties. The phasin protein derived from Pseudomonas sp. B14-6 revealed higher PHB production and exhibited higher tolerance to several lignocellulosic biosugar-based inhibitors than the phasin protein of Ralstonia eutropha H16 in a recombinant Escherichia coli strain. The increased tolerance to propionate, temperature, and other inhibitors was attributed to the introduction of phaP1Ps, which increased PHB production from lignocellulosic hydrolysate (2.39-fold) in the phaP1Ps strain. However, a combination of phasin proteins isolated from two different sources did not increase PHB production. These findings suggest that phasin could serve as a powerful means to increase robustness and PHB production in heterologous strains.

Densities, ultrasonic velocity, conductance and viscosity of some alkaline earth metal chlorides such as magnesium chloride (MgCl2) and calcium chloride (CaCl2) were calculated in the concentration range (0.01–0.12 mol kg−1) in 0.01 mol kg−1 aqueous solution of citric acid (CA + H2O) at four varying temperatures T 1 = 303.15 K, T 2 = 308.15 K, T 3 = 313.15 K and T 4 = 318.15 K. The parameters like apparent molar volume (ϕ v ), limiting apparent molar volume ( ϕ v o ${\phi }_{v}^{o}$ ) and transfer volume (Δtr ϕ v o ${\phi }_{v}^{o}$ ) were calculated from density data. Viscosity data have been employed to calculate Falkenhagen coefficient (A), Jone–Dole’s coefficient (B), relative viscosity (η r ), and relaxation time (τ) whereas limiting molar conductance ( Λ m o ${{\Lambda}}_{m}^{o}$ ) has been evaluated from conductance studies. Using these parameters, various type of interactions occurred in the molecules have been discussed. Values of Hepler’s constant (d 2 ϕ v o ${\phi }_{v}^{o}$ /dT 2) p , (dB/dT) and d( Λ m o ${{\Lambda}}_{m}^{o}$ η o )/dT suggests that both MgCl2 and CaCl2 behave as structure breaker in (CA + H2O) system. The positive value of transfer volume exclusively tells about solute–solvent interactions which further indicate that both metal chlorides distort the structure of water and act as structure breaker. These studies are helpful in understanding the nature of interactions occurs in biological systems as CA and metal salts are essential for normal functioning of body.

Whole-cell systems offer many benefits for biochemical production, such as relatively easy enzyme control and higher tolerance toward harsh environments, than purified enzymes. These systems can be applied to many bioconversion reactions, but they sometimes require cofactor regeneration units to support reactions at high substrate concentrations. Here, we examined l-glutamate oxidase (GOX) from Streptomyces sp. X119-6, which produces α-ketoglutarate (α-KG) from l-glutamate, and catalase (KatE) from Escherichia coli, which removes hydrogen peroxide generated by GOX. After optimizing the expression vector, pH, strains, culture conditions, and isopropyl β-d-1-thiogalactopyranoside concentration, we compared their efficiency to that of a previously reported GOX from Streptomyces mobaraensis. Our results indicated that GOX from Streptomyces sp. X119-6 and KatE increased α-KG production by 2.76-fold. This GOX required high levels of α-KG as an amino donor to convert 5-aminovaleric acid to glutaric acid. Performing the reaction at pH 8 enabled us to avoid the exogenous addition of catalase, but severe substrate inhibition was observed, resulting in the production of 287 mM glutaric acid. This α-KG regeneration system has potential for improving production in various aminotransferase systems.

This prospective study was conducted on 42 buffaloes diagnosed with reticular diaphragmatic hernia (RDH). The common clinical findings were depressed demeanor, chronic inappetance or anorexia, dehydration, recurrent or persistent tympany, scanty faeces, mushy rumen with normal or increased motility, tachypnea, abdominal distension, and gradual reduction in milk yield. The presence of reticular foreign bodies seemed to be the major predisposing factor. Neutrophil and lymphocyte counts were significantly (p

Polyhydroxybutyrate (PHB) is a biodegradable plastic that can be used as an alternative to petrochemical-based plastics. PHB is produced by various microorganisms such as Ralstonia, Halomonas, and Bacillus species. However, there are very few strains that produce PHB using xylose, an abundant and inexpensive carbon source. In this study, ten xylose-utilizing PHB producers isolated from South Korean marine environments were screened and characterized. Among these isolates, Bacillus sp. SM01, a newly identified strain, produced the highest amount of PHB using xylose. Under optimal conditions, the maximum dry cell weight (DCW) was 3.41 ± 0.09 g/L, with 62% PHB content, and Bacillus sp. SM01 showed Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer production with propionate; however, the growth of Bacillus sp. SM01 was greatly inhibited by the presence of glucose. Co-culturing Bacillus sp. SM01 with Cupriavidus necator NCIMB 11599 resulted in increased DCW, PHB production, and utilization of glucose and xylose, the main sugar of lignocellulosic biomass, compared with the monoculture. Our results indicated that this co-culture system can be used to increase PHB production and overcome the limitation of sugar consumption associated with Bacillus sp. SM01 and C. necator.

Poly(3-hydroxybutyrate) (PHB) is a biobased and biodegradable plastic. Considering the environmental issues of petroleum-based plastics, PHB is promising as it can be degraded in a relatively short time by bacteria to water and carbon dioxide. Substantial efforts have been made to identify PHB-degrading bacteria. To identify PHB-degrading bacteria, solid-based growth or clear zone assays using PHB as the sole carbon source are the easiest methods; however, PHB is difficult to dissolve and distribute evenly, and bacteria grow slowly on PHB plates. Here, we suggest an improved PHB plate assay using cell-grown PHB produced by Halomonas sp. and recovered by sodium dodecyl sulfate (SDS). Preparation using SDS resulted in evenly distributed PHB plates that could be used for sensitive depolymerase activity screening in less time compared with solvent-melted pellet or cell-grown PHB. With this method, we identified 15 new strains. One strain, Cutibacterium sp. SOL05 (98.4% 16S rRNA similarity to Cutibacterium acne), showed high PHB depolymerase activity in solid and liquid conditions. PHB degradation was confirmed by clear zone size, liquid culture, scanning electron microscopy, and Fourier-transform infrared spectroscopy. The results indicate this method can be used to easily identify PHB-degrading bacteria from various sources to strengthen the benefits of bioplastics.

Cadaverine, 1,5-diaminopentane, is one of the most promising chemicals for biobased-polyamide production and it has been successfully produced up to molar concentration. Pyridoxal 5′-phosphate (PLP) is a critical cofactor for inducible lysine decarboxylase (CadA) and is required up to micromolar concentration level. Previously the regeneration of PLP in cadaverine bioconversion has been studied and salvage pathway pyridoxal kinase (PdxY) was successfully introduced; however, this system also required a continuous supply of adenosine 5′-triphosphate (ATP) for PLP regeneration from pyridoxal (PL) which add in cost. Herein, to improve the process further a method of ATP regeneration was established by applying baker’s yeast with jhAY strain harboring CadA and PdxY, and demonstrated that providing a moderate amount of adenosine 5′-triphosphate (ATP) with the simple addition of baker’s yeast could increase cadaverine production dramatically. After optimization of reaction conditions, such as PL, adenosine 5′-diphosphate, MgCl2, and phosphate buffer, we able to achieve high production (1740 mM, 87% yield) from 2 M l-lysine. Moreover, this approach could give averaged 80.4% of cadaverine yield after three times reactions with baker’s yeast and jhAY strain. It is expected that baker’s yeast could be applied to other reactions requiring an ATP regeneration system.

Poly(3-hydroxybutyrate) (PHB) is a common polyhydroxyalkanoate (PHA) with potential as an alternative for petroleum-based plastics. Previously, we reported a new strain, Halomonas sp. YLGW01, which hyperproduces PHB with 94% yield using fructose. In this study, we examined the PHB production machinery of Halomonas sp. YLGW01 in more detail by deep-genome sequencing, which revealed a 3,453,067-bp genome with 65.1% guanine-cytosine content and 3054 genes. We found two acetyl-CoA acetyltransferases (Acetoacetyl-CoA thiolase, PhaA), one acetoacetyl-CoA reductase (PhaB), two PHB synthases (PhaC1, PhaC2), PHB depolymerase (PhaZ), and Enoyl-CoA hydratase (PhaJ) in the genome, along with two fructose kinases and fructose transporter systems, including the phosphotransferase system (PTS) and ATP-binding transport genes. We then examined the PHB production by Halomonas sp. YLGW01 using high-fructose corn syrup (HFCS) containing fructose, glucose, and sucrose in sea water medium, resulting in 7.95 ± 0.11 g/L PHB (content, 67.39 ± 0.34%). PHB was recovered from Halomonas sp. YLGW01 using different detergents; the use of Tween 20 and SDS yielded micro-sized granules with high purity. Overall, these results reveal the distribution of PHB synthetic genes and the sugar utilization system in Halomonas sp. YLGW01 and suggest a possible method for PHB recovery.

Four new complexes of composition [MII2(L3)2(CH3OH)2](ClO4)2 (M = Mn, 1; Co, 2; Ni, 3) and [CuII2(L3)2](ClO4)2 (4) (L3(−) = 3-[2-(((6-methyl)pyridin-2-yl)methyl){(dimethylamino)ethyl}-amino]propionate) have been synthesized and characterized. Structural analysis reveals that 1–4 are discrete syn–anti carboxylate-bridged binuclear coordination complexes with a {MII2(–O–C–O–)2}2+ structural motif. In 1–3 distorted octahedral MN3O3 and in 4 distorted square pyramidal CuN3O2 coordination is satisfied at each M(II) center by three N (a pyridyl and two tertiary aliphatic amines) and a carboxylate O of the ligand, and an O of the carboxylate group. In 1–3 the M(II) center is also coordinated by a CH3OH molecule. Variable-temperature magnetic measurements reveal the presence of weak antiferromagnetic interactions in 1 and weak ferromagnetic interactions in 2–4. The electronic structure of 1–4 has been probed by density functional theory (DFT) calculations at the B3LYP level of theory. In order to gain insight into the origin of the observed electronic transitions, time-dependent (TD)-DFT calculations have been done.

Psychrophilic bacteria, living at low and mild temperatures, can contribute significantly to our understanding of microbial responses to temperature, markedly occurring in the bacterial membrane. Here, a newly isolated strain, Pseudomonas sp. B14-6, was found to dynamically change its unsaturated fatty acid and cyclic fatty acid content depending on temperature which was revealed by phospholipid fatty acid (PLFA) analysis. Genome sequencing yielded the sequences of the genes Δ-9-fatty acid desaturase (desA) and cyclopropane-fatty acid-acyl-phospholipid synthase (cfa). Overexpression of desA in Escherichia coli led to an increase in the levels of unsaturated fatty acids, resulting in decreased membrane hydrophobicity and increased fluidity. Cfa proteins from different species were all found to promote bacterial growth, despite their sequence diversity. In conclusion, PLFA analysis and genome sequencing unraveled the temperature-related behavior of Pseudomonas sp. B14-6 and the functions of two membrane-related enzymes. Our results shed new light on temperature-dependent microbial behaviors and might allow to predict the consequences of global warming on microbial communities.

γ-Aminobutyric acid (GABA), an important fine chemical in pharmacotherapy and food industries, is used as a novel material in the nylon industry and has attracted attention for its potential application in large scale production. Search for new genes and strains, development of efficient reaction systems, such as fermentation and bioconversion, and use of cheap starting material like monosodium glutamate (MSG) can make GABA production using less expensive bulk chemicals possible. Therefore, in this study, we constructed a recombinant Escherichia coli whole-cell system for GABA production that expressed glutamate decarboxylase (GAD) from Lactobacillus brevis and used MSG as the starting material. We also optimized the reaction conditions for MSG to GABA conversion, such as citrate buffer concentration, pyridoxal 5′te concentration, temperature, MSG concentration, and cell density (OD600). The optimized whole-cell system converted MSG to GABA via seven repetitive cycles resulting in an average conversion rate of 86% (71.7 mM/h) within 42 h.

Neurogenesis is a developmental process that involves fine-tuned coordination between self-renewal, proliferation, and differentiation of neural stem cells (NSCs) into neurons. However, early-life assault with environmental toxicants interferes with the regular function of genes, proteins, and other molecules that build brain architecture resulting in attenuated neurogenesis. Cypermethrin is a class II synthetic pyrethroid pesticide extensively used in agriculture, veterinary, and residential applications due to its low mammalian toxicity, high bio-efficacy, and enhanced stability. Despite reports on cypermethrin-mediated behavioral and biochemical alterations, till now, no study implicates whether cypermethrin exposure has any effect on neurogenesis. Therefore, the present study was undertaken to comprehend the effects of cypermethrin treatment on embryonic and adult neurogenesis. We found that cypermethrin exposure led to a considerable decrease in the BrdU/Sox-2+, BrdU/Dcx+, and BrdU/NeuN+ co-labeled cells indicating that cypermethrin treatment decreases NSC proliferation and generation of mature and functional neurons. On the contrary, the generation of BrdU/S100β+ glial cells was increased resulting in neurogliogenesis imbalance in the hippocampus. Further, cypermethrin treatment also led to an increased number of BrdU/cleaved caspase-3+ and Fluoro-Jade B+ cells suggesting an induction of apoptosis in NSCs and increased degeneration of neurons in the hippocampus. Overall, these results explicate that cypermethrin exposure not only reduces the NSC pool but also disturbs the neuron–astrocyte ratio and potentiates neurodegeneration in the hippocampus, leading to cognitive dysfunctions in rats.

Objective: This study was designed to compare different doses of cis-atracurium (2×ED95, 4×ED95, 6×ED95) in regarding onset time, condition of intubation , duration of action, hemodynamic effects, and signs of histamine release. Methods: Sixty ASA I and II adult patients undergoing abdominal surgery under general anesthesia were included in this prospective, randomised, double blind study. Patients were allocated to one of three groups: Group 1:Patients in this group received with initial dose of 0.1 mg/kg (2×ED95) of cis- atracurium. Group 2:Received initial dose of 0.2 mg/kg (4×ED95). Group 3:Received initial dose of 0.3 mg/kg (6×ED95). Result: All the demographic parameters were comparable.There was a statistically significant increase in HR, MABP post intubation when compared to baseline and post injection of 2× ED95 dose of cis-atracurium in group 1. Higher doses of cisatracurium (4×ED95 and 6×ED95) showed onset time that was significantly lower than cisatracurium (2×ED95). Regarding the duration of action, higher doses of cisatracurium (4×ED95 and 6×ED95) showed statistically significant longer duration of action than lower doses of cisatracurium.4×ED95 and 6×ED95 doses of cisatracurium were significantly better than 2×ED95 dose of cisatracurium. Only 6×ED95 dose of cisatracurium was statistically significant with higher percentages of patients with excellent condition of intubation. Conclusion: We can conclude that the higher doses of cisatracurium provide more effective, more rapid neuromuscular blocking with longer duration of action, stable hemodynamic status, and no associated signs of histamine release clinically.

Naturally degradable bioplastic polyhydroxyalkanoate (PHA) is a promising biopolymer and its physical properties could be changed by introducing of different monomers such as 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyhexanoate (3HHx). To produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV)) including a high fraction of hydroxyvalerate, we introduced ctfAB into engineered Escherichia coli YJ200 possessing a pLW487 vector containing bktB, phaB, and phaC under control of the trc promoter. To enhance the HV fraction of P(3HB-co-3HV), the optimal concentrations of propionate, which acts as a precursor of 3HV and isopropyl β-D-1-thiogalactopyranoside, were determined and found to be 0.1 mM and 0.3%, respectively. Under the optimized conditions, E. coli, YJ201 produced P(3HB-co-3HV) containing a large amount of 3HV. Comparison with other CoA transferases showed that CtfAB produced relatively lower molecular weight copolymers. This demonstrates the necessity of identifying additional different CoA transferases, because CoA transferase can affect both the monomer fraction and molecular weight of polymers.

In the present research, the high temperature oxidation behaviour of Wire Arc sprayed Ni-5Al coating on T-11 and Gr-A1 boiler steels was studied at 9000C for 50 cycles. Each cycle consisted of 1 hour heating at 9000C followed by 20 min of cooling in air at room temperature. The kinematics of oxidation was established using weight change measurements for the bare and coated boiler steels. The oxidized samples were characterized using XRD, SEM/EDS, X-Ray mapping analyses. The coating was found to offer excellent oxidation resistance to the base steels. This may be attributed to the formation of strong protective chromium aluminium oxide phases.

Biologists and engineers are making tremendous efforts in contributing to a sustainable and green society. To that end, there is growing interest in waste management and valorisation. Lignocellulosic biomass (LCB) is the most abundant material on the earth and an inevitable waste predominantly originating from agricultural residues, forest biomass and municipal solid waste streams. LCB serves as the renewable feedstock for clean and sustainable processes and products with low carbon emission. Cellulose and hemicellulose constitute the polymeric structure of LCB, which on depolymerisation liberates oligomeric or monomeric glucose and xylose, respectively. The preferential utilization of glucose and/or absence of the xylose metabolic pathway in microbial systems cause xylose valorization to be alienated and abandoned, a major bottleneck in the commercial viability of LCB-based biorefineries. Xylose is the second most abundant sugar in LCB, but a non-conventional industrial substrate unlike glucose. The current review seeks to summarize the recent developments in the biological conversion of xylose into a myriad of sustainable products and associated challenges. The review discusses the microbiology, genetics, and biochemistry of xylose metabolism with hurdles requiring debottlenecking for efficient xylose assimilation. It further describes the product formation by microbial cell factories which can assimilate xylose naturally and rewiring of metabolic networks to ameliorate xylose-based bioproduction in native as well as non-native strains. The review also includes a case study that provides an argument on a suitable pathway for optimal cell growth and succinic acid (SA) production from xylose through elementary flux mode analysis. Finally, a product portfolio from xylose bioconversion has been evaluated along with significant developments made through enzyme, metabolic and process engineering approaches, to maximize the product titers and yield, eventually empowering LCB-based biorefineries. Towards the end, the review is wrapped up with current challenges, concluding remarks, and prospects with an argument for intense future research into xylose-based biorefineries., Biologists and engineers are making tremendous efforts in contributing to a sustainable and green society.

Objective: Fluid shear stress (FSS) is known to mediate multiple phenotypic changes in the endothelium. Laminar FSS (undisturbed flow) is known to promote endothelial alignment to flow, which is key to stabilizing the endothelium and rendering it resistant to atherosclerosis and thrombosis. The molecular pathways responsible for endothelial responses to FSS are only partially understood. In this study, we determine the role of PGC1α (peroxisome proliferator gamma coactivator-1α)-TERT (telomerase reverse transcriptase)-HMOX1 (heme oxygenase-1) during shear stress in vitro and in vivo. Approach and Results: Here, we have identified PGC1α as a flow-responsive gene required for endothelial flow alignment in vitro and in vivo. Compared with oscillatory FSS (disturbed flow) or static conditions, laminar FSS (undisturbed flow) showed increased PGC1α expression and its transcriptional coactivation. PGC1α was required for laminar FSS-induced expression of TERT in vitro and in vivo via its association with ERRα(estrogen-related receptor alpha) and KLF (Kruppel-like factor)-4 on the TERT promoter. We found that TERT inhibition attenuated endothelial flow alignment, elongation, and nuclear polarization in response to laminar FSS in vitro and in vivo. Among the flow-responsive genes sensitive to TERT status, HMOX1 was required for endothelial alignment to laminar FSS. Conclusions: These data suggest an important role for a PGC1α-TERT-HMOX1 axis in the endothelial stabilization response to laminar FSS.

Glucosamine (Gln) is a universal amino sugar, present in animals, plants, and microbes as a major component of various structural polymers, i.e. chitin, chitosan, and peptidoglycans. Besides structural applications, several experimental and clinical trials have shown its tremendous applications in the health sector especially in the case of cancer, osteoarthritis (OA), allergy, and inflammation-associated complications. Wider and safer applications for Gln increased its volumetric demand and market share exponentially. Different methods of Gln production such as direct extraction from sea waste (chitin) and plants biomass have been reported. However, phytoextraction and chemical hydrolysis of chitinous wastes are suffered from limited yield and high production costs. In recent years, microbial/enzymatic hydrolysis has taken over the market due to economic and eco-friendly production. In addition, genetically modified bacterial fermentation is also under development stage. In this review, recent progress related to Gln production from different resources and its various applications is reviewed in detail.

In this study, a newly isolated halotolerant strain Oceanisphaera arctica YHY1, capable of hydrolyzing seafood processing waste chitin biomass, is reported. Microbial fuel cells fed with 1% chitin and 40 g L−1 as the optimum salt concentration demonstrated stable electricity generation until 216 h (0.228 mA/cm2). N-acetyl-D-glucosamine (GlcNAc) was the main by-product in the chitin degradation, reaching a maximum concentration of 192.01 mg g−1 chitin at 120 h, whereas lactate, acetate, propionate, and butyrate were the major metabolites detected in the chitin degradation. O. arctica YHY1 utilized the produced GlcNAc, lactate, acetate, and propionate as the electron donors to generate the electric current. Cyclic voltammetry (CV) investigation revealed the participation of outer membrane-bound cytochromes, with extracellular redox mediators partly involved in the electron transfer mechanism. Furthermore, the changes in structural and functional groups in chitin after degradation were analyzed using FTIR and XRD. Therefore, the ability of O. arctica YHY1 to utilize waste chitin biomass under high salinities can be explored to treat seafood processing brine or high salt wastewater containing chitin with concurrent electricity generation.

In this work, CO2 absorption capacities in a series of aqueous N-alkyl-N-methylmorpholinium-based ILs with acetate as the counterpart anion were investigated. Among these ILs, N-butyl-N-methylmorph ...

Bioconversion of recalcitrant keratinous biomass is one of the greatest ways to utilize products of feather hydrolysis and recycle them into bionetwork. Present study revealed 87% degradation of poultry feathers within 48 h in a constructed bioreactor using Chryseobacterium sp. RBT. The resulting feather hydrolysate (FH) was rich in soluble protein (3.56 ± 0.18 mg/ml), amino acids (3.83 ± 0.20 mg/ml), and macro and micro nutrients like N (8.0302%), P (0.3876%), K (0.5532%), Cu (0.0684%), Mg (0.8078%), Mn (0.2001%), Ca (0.4832%), Zn (0.0442%), and Fe (0.0330%). HPTLC analysis of FH revealed presence of tryptophan, cysteine, methionine, phenylalanine, glycine, valine, tyrosine, lysine, leucine, and serine as the primary amino acids. Field studies were conducted to apply FH as the bioenhancer to commercially important crops like brinjal and chilli through root drenching (20%, v/v). FH showed positive impact on the growth and development of plants along with early flowering and improved crop yield. In addition, nutritional quality of brinjal and chilli in terms of protein, amino acids, reducing sugars, phenolics, flavonoids, and antioxidant was elevated. Therefore, promotion and utility of by-products generated in feather degradation would be an effective strategy focusing on sustainable agricultural practices and problems associated with the waste management.

The experimental values of density, ρ and speed of sound, u of doxycycline hyclate drug (0.002–0.014) mol kg−1 in water and (0.1, 0.2 and 0.4) mol kg−1 of aqueous galactitol solutions at temperatures T = (303.15, 308.15 and 313.15) K and at atmospheric pressure have been reported in the present communication. From the experimental values, various derived parameters such as apparent molar volume (Φ V), apparent molar isentropic compression (Φ K), limiting apparent molar volume ( Φ v o $\phi_{\text{v}}^{\text{o}}$ ), limiting apparent molar isentropic compression ( Φ K o $\phi_{\text{K}}^{\text{o}}$ ), limiting apparent molar volume of transfer (Δ Φ V O $\phi_{\text{V}}^{\text{O}}$ ), limiting apparent molar isentropic compression of transfer (Δ Φ K O $\phi_{\text{K}}^{\text{O}}$ ), limiting apparent molar expansibility ( Φ E o $\phi_{\text{E}}^{\text{o}}$ ), thermal expansion coefficient (α) and acoustic parameters like isentropic compressibility ( κ S ) $({{\kappa}_{\text{S}}})$ , intermolecular free length (Lf), and specific acoustic impedance (Z) were calculated. The structure-making behaviour of DH in aqueous galactitol solution was determined on the basis of Hepler’s Equation i.e. on the basis of sign of ( d 2 Φ V O d T 2 ) P ${\left({\frac{{{{\text{d}}^{2}}\phi_{\text{V}}^{\text{O}}}}{{{\text{d}}{{\text{T}}^{2}}}}}\right)_{\text{P}}}$ . The various derived parameters were utilised to interpret the molecular interactions i.e. solute–solute and solute–solvent existing in the studied system.

One of the advantages of microbial synthesis of polyhydroxyalkanoates (PHAs) is the production of diverse polymers with different properties by the addition of different monomers, such as 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyhexanoate (3HHx). Considering the number of possible variables, terpolymers can have more variations than copolymers. In this study, we aimed to synthesize the terpolymer P(3HB-co-3HV-co-3HHx) from volatile fatty acids such as propionate and butyrate using the recombinant Ralstonia eutropha strain (Re2133/pCB81), containing deletions in the phaB1, phaB2, and phaB3 genes, and overexpression of synthetic PHA operon (phaC2, phaA, phaJ). This strain produced terpolymers depending on the ratio of two different carbon sources, namely, propionic and butyric acids; however, wild type R. eutropha could not produce the same type of polymer. The incorporation of 3-hydroxyvalerate and 3-hydroxyhexanoate monomers was confirmed by gas chromatography and H-nuclear magnetic resonance spectroscopy, and the parameters affecting the terpolymer composition were obtained based on regression. In addition, the thermal analysis showed that this terpolymer has properties different from those of the copolymer, obtained from the same composition of volatile acids. Depending on the ratio of two volatile acids, the composition of the terpolymer can be regulated resulting in different properties.

The present work elucidates about the structure of bioactive glasses having chemical compositions expressed as (mol %) (50.0 - x)SiO2-xB2O3-9.3Na2O-37CaO-3.7P2O5, where x = 0.0, 12.5, 25, and 37.5, and establishes a correlation between the structure and thermal stability. The structural modifications in the parent boron-free glass (B0) with the gradual substitutions of B2O3 for SiO2 are assessed by Raman and 29Si, 31P, 11B, and 23Na magic angle spinning (MAS)-nuclear magnetic resonance (NMR) spectroscopies. The structural studies reveal the presence of QSi2 and QSi3 structural units in both silicate and borosilicate glasses. However, QSi4(3B) units additionally form upon incorporating B2O3 in B0 glass. B-containing silicate glasses exhibit both three-coordinated boron (BIII) and four-coordinated boron (BIV) units. The 31P MAS-NMR studies reveal that the majority of phosphate species exist as isolated orthophosphate (QP0) units. The incorporation of B2O3 in B0 glass increases the cross-linking between the SiO4 and BO4 structural units. However, incorporation of B2O3 lowers the glass thermal stability (ΔT), as shown by differential scanning calorimetry. Although both silicate and borosilicate glasses exhibit good in vitro apatite-forming ability and cell compatibility, the bactericidal action against Escherichia coli bacteria is more evident in borosilicate glass in comparison to silicate base glass. The controlled release of (BO3)3- ions from boron-modified bioactive glasses improves both the cell proliferation and the antibacterial properties, making them promising for hard tissue engineering applications.

Cadaverine, also known as 1,5-pentanediamine, is an important platform chemical with a wide range of applications and can be produced either by fermentation or bioconversion. Bioconversion of cadaverine from l -lysine is the preferred method because of its many benefits, including rapid reaction time and an easy downstream process. In our previous study, we replaced pyridoxal-5-phosphate (PLP) with pyridoxal kinase (PdxY) along with pyridoxal (PL) because it could achieve 80% conversion with 0.4 M of l -lysine in 6 h. However, conversion was sharply decreased in the presence of high concentrations of l -lysine (i.e., 1 M), resulting in less than 40% conversion after several hours. In this study, we introduced an ATP regeneration system using polyphosphate kinase (ppk) into systems containing cadaverine decarboxylase (CadA) and PdxY for a sufficient supply of PLP, which resulted in enhanced cadaverine production. In addition, to improve transport efficiency, the use of surfactants was tested. We found that membrane permeabilization via hexadecyltrimethylammonium bromide (CTAB) increased the yield of cadaverine in the presence of high concentrations of l -lysine. By combining these two strategies, the ppk system and addition of CTAB, we enhanced cadaverine production up to 100% with 1 M of l -lysine over the course of 6 h.

With the growing use of fossil fuels and industrial activity, the amount of carbon dioxide (CO2) emission is continuously increasing and is considered a primary contributor to climate change. CO2 emissions from stationary resources (coal fire, cement plants, and other industry) can be reduced by using various carbon capture and sequestration (CCS) technologies. In this article, recent advancements in various biological methods (i.e., carbonic anhydrase (CA), hydrogenation of CO2 to formate, reduction of CO2 to methane, CO2 conversion into methanol by enzyme cascade, and the role of RuBisCo enzyme) that have been reported for CO2 capture are discussed, along with their advantages and limitations. A brief overview of other physicochemical (absorption, adsorption, cryogenic, and membrane) technologies is also provided. Although biological methods are ecofriendly and can be performed under ambient conditions, these approaches are still not cost effective, as the reactions require cofactors, and the enzymes lose activity when exposed to hot flue gas and ionic liquids. Most captured CO2 is stored by mineralization using a geological and ocean storage method without providing any economic benefit. It is a question of interest as to how we can utilize CO2 and generate revenue. Utilization of CO2 as a feedstock to produce bioenergy is a possible approach. Various microbes capable of utilizing CO2 as feedstock and producing biofuels (biodiesel and bioalcohol) have been reported. These two technologies, i.e., CO2 capture and bioconversion of CO2 into bioenergy, can be integrated to develop a process that not only mitigates CO2 effects on the environment but also solves energy problems while generating revenue.

Polyhydroxybutyrate (PHB), the most well-known polyhydroxyalkanoate, is a bio-based, biodegradable polymer that has the potential to replace petroleum-based plastics. Lignocellulose hydrolysate, a non-edible resource, is a promising substrate for the sustainable, fermentative production of PHB. However, its application is limited by the generation of inhibitors during the pretreatment processes. In this study, we investigated the feasibility of PHB production in E. coli in the presence of inhibitors found in lignocellulose hydrolysates. Our results show that the introduction of PHB synthetic genes (bktB, phaB, and phaC from Ralstonia eutropha H16) improved cell growth in the presence of the inhibitors such as furfural, 4-hydroxybenzaldehyde, and vanillin, suggesting that PHB synthetic genes confer resistance to these inhibitors. In addition, increased PHB production was observed in the presence of furfural as opposed to the absence of furfural, suggesting that this compound could be used to stimulate PHB production. Our findings indicate that PHB production using lignocellulose hydrolysates in recombinant E. coli could be an innovative strategy for cost-effective PHB production, and PHB could be a good target product from lignocellulose hydrolysates, especially glucose.

This paper reports highly sensitive and selective ethanol sensing performance of ZnO thin films in a resistive configuration. ZnO thin films were grown by RF sputtering on a Si substrate at room temperature under a controlled environment. The grown film was characterized by x-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM) and atomic force microscopy. XRD analysis reveals a crystalline size of ∼ 73 nm with preferential (002) plane growth along the c-axis, and FESEM confirms a uniform film with nanoplate like structures. Ethanol sensing performance of the ZnO based device with Al as contacts were carried out in the temperature range of 50–200°C for concentrations of 1–400 ppm. The highest response magnitude of ∼ 95% was obtained at 200°C with fast response and recovery time of ∼ 27 s and ∼ 25 s, respectively. Sensor responses of other similar volatile organic compounds confirms the high selectivity of ZnO nanoplates towards ethanol sensing. The ethanol sensing mechanism of the ZnO thin film is discussed considering adsorption–desorption kinetics under different ambient conditions and defect states.

A novel marine bacterium Arenibacter palladensis YHY2 isolated from Eastern Sea, South Korea revealed hydrolysing ability of crab chitin in shake flask and microbial fuel cell (MFC) systems. Under shake flask cultivation, strain YHY2 demonstrated 71.44 ± 1.90 U/ml chitinase activity with the microbial cell optical density (OD) 0.699 ± 0.021. High performance liquid chromatography (HPLC) results showed N-acetylglucosamine (GlcNAc) as the major by-product of chitin degradation. Furthermore, Ralstonia eutropha H16 which has carbon utilization limited to GlcNAc and fructose was co-cultivated with YHY2 to consume GlcNAc and accumulate polyhydroxyalkanoates (PHA). However, on co-cultivating strain YHY2 with H16 surprisingly showed higher production of chitinase (97.89 ± 2.72 U/ml) and GlcNAc (80.31 mg GlcNAc/g chitin) corresponding to the microbial cell OD (1.065 ± 0.005) at 120 h. In addition, marine strain YHY2 demonstrated biofilm formation, hence co-cultivation of strain YHY2 and H16 under MFC system was performed to check the electricity production. Maximum electricity current output density was 15.15 μA/cm2 at the initial stage and 10.72 μA/cm2 at 204 h. GlcNAc (196.34 mg GlcNAc/g chitin) was produced along with other metabolites like butyrate, acetate, lactate, and propionate in MFC system. The microbial cell biomass from MFC was analysed for PHA content showed 1.020 g/l of 3-polyhydroxybutyrate (PHB) and 0.198 g/l of 3-polyhydroxyvalerate (PHV) as the main components of PHA. Moreover, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were performed to reveal changes in chitin before and after degradation. Thus, the exploitation of recalcitrant chitin biomass for simultaneous production of GlcNAc, electricity, and PHA in one-pot MFC system was the productive asset for sustainable development.

Naturally produced polyhydroxyalkanoates (PHAs) biopolymers have limited medical applications due to their brittle and hydrophobic nature. In this study poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV) copolymer was produced using engineered Escherichia coli YJ101, and further functionalized with ascorbic acid using Candida antarctica lipase B mediated esterification. Copolymer P(3HB-co-3HV)-ascorbic acid showed lower degree of crystallinity (9.96%), higher thermal degradation temperature (294.97 °C) and hydrophilicity (68°) as compared to P(3HB-co-3HV). Further, P(3HB-co-3HV)-ascorbic acid biomaterial showed 14% scavenging effect on 1,1-diphenyl-2-picryl-hydrazyl (DPPH), and 1.6 fold increase in biodegradability as compared to P(3HB-co-3HV). Improvement of PHAs polymer properties by adding functional groups could be a good approach to increase their biodegradability, economic value and important applications in the medical field.

Equivalent donor and acceptor tendencies in DESs bring strong synergistic interaction into play and result in high CO2 uptake by lowering the ΔH° and ΔS°.

Herein, we have studied the potential of lutidinium-based ionic liquids in the dissolution of cellulose as confirmed by the X-ray diffraction (XRD), scanning electron microscopy (SEM) and 13C CP/MAS NMR, spectroscopic methods.

Fluid shear stress (FSS) is known to mediate multiple phenotypic changes in the endothelium. Laminar FSS (undisturbed flow) is known to promote endothelial alignment to flow that is key to stabilizing the endothelium and rendering it resistant to atherosclerosis and thrombosis. The molecular pathways responsible for endothelial responses to FSS are only partially understood. Here we have identified peroxisome proliferator gamma coactivator-1α (PGC-1α) as a flow-responsive gene required for endothelial flow alignment in vitro and in vivo. Compared to oscillatory FSS (disturbed flow) or static conditions, laminar FSS (undisturbed flow) increased PGC-1α expression and its transcriptional co-activation. PGC-1α was required for laminar FSS-induced expression of telomerase reverse transcriptase (TERT) in vitro and in vivo via its association with ERRα and KLF4 on the TERT promoter. We found that TERT inhibition attenuated endothelial flow alignment, elongation, and nuclear polarization in response to laminar FSS in vitro and in vivo. Among the flow-responsive genes sensitive to TERT status was heme oxygenase-1 (HMOX1), a gene required for endothelial alignment to laminar FSS. Thus, these data suggest an important role for a PGC-1α-TERT-HMOX1 axis in the endothelial stabilization response to laminar FSS.

Arctic bacteria employ various mechanisms to survive harsh conditions, one of which is to accumulate carbon and energy inside the cell in the form of polyhydroxyalkanoate (PHA). Whole-genome sequencing of a new Arctic soil bacterium Pseudomonas sp. B14-6 revealed two PHA-production-related gene clusters containing four PHA synthase genes (phaC). Pseudomonas sp. B14-6 produced poly(6% 3-hydroxybutyrate-co-94% 3-hydroxyalkanoate) from various carbon sources, containing short-chain-length PHA (scl-PHA) and medium-chain-length PHA (mcl-PHA) composed of various monomers analyzed by GC-MS, such as 3-hydroxybutyrate, 3-hydroxyhexanoate, 3-hydroxyoctanoate, 3-hydroxydecanoate, 3-hydroxydodecenoic acid, 3-hydroxydodecanoic acid, and 3-hydroxytetradecanoic acid. By optimizing the PHA production media, we achieved 34.6% PHA content using 5% fructose, and 23.7% PHA content using 5% fructose syrup. Differential scanning calorimetry of the scl-co-mcl PHA determined a glass transition temperature (Tg) of 15.3 °C, melting temperature of 112.8 °C, crystallization temperature of 86.8 °C, and 3.82% crystallinity. In addition, gel permeation chromatography revealed a number average molecular weight of 3.6 × 104, weight average molecular weight of 9.1 × 104, and polydispersity index value of 2.5. Overall, the novel Pseudomonas sp. B14-6 produced a polymer with high medium-chain-length content, low Tg, and low crystallinity, indicating its potential use in medical applications.

Methamphetamine (METH) is a potent stimulant that induces a euphoric state but also causes cognitive impairment, neurotoxicity and neurodevelopmental deficits. Yet, the molecular mechanisms by which METH causes neurodevelopmental defects have remained elusive. Here we utilized human cerebral organoids and single-cell RNA sequencing (scRNA-seq) to study the effects of prenatal METH exposure on fetal brain development. We analyzed 20,758 cells from eight untreated and six METH-treated cerebral organoids and found that the organoids developed from embryonic stem cells contained a diverse array of glial and neuronal cell types. We further identified transcriptionally distinct populations of astrocytes and oligodendrocytes within cerebral organoids. Treatment of organoids with METH-induced marked changes in transcription in multiple cell types, including astrocytes and neural progenitor cells. METH also elicited novel astrocyte-specific gene expression networks regulating responses to cytokines, and inflammasome. Moreover, upregulation of immediate early genes, complement factors, apoptosis, and immune response genes suggests a neuroinflammatory program induced by METH regulating neural stem cell proliferation, differentiation, and cell death. Finally, we observed marked METH-induced changes in neuroinflammatory and cytokine gene expression at the RNA and protein levels. Our data suggest that human cerebral organoids represent a model system to study drug-induced neuroinflammation at single-cell resolution.

Polyhydroxyalkanoates (PHAs) are attractive new bioplastics for the replacement of plastics derived from fossil fuels. With their biodegradable properties, they have also recently been applied to the medical field. As poly(3-hydroxybutyrate) produced by wild-type Ralstonia eutropha has limitations with regard to its physical properties, it is advantageous to synthesize co- or terpolymers with medium-chain-length monomers. In this study, tung oil, which has antioxidant activity due to its 80% α-eleostearic acid content, was used as a carbon source and terpolymer P(53 mol% 3-hydroxybytyrate-co-2 mol% 3-hydroxyvalerate-co-45 mol% 3-hydroxyhexanoate) with a high proportion of 3-hydroxyhexanoate was produced in R. eutropha Re2133/pCB81. To avail the benefits of α-eleostearic acid in the tung oil-based medium, we performed partial harvesting of PHA by using a mild water wash to recover PHA and residual tung oil on the PHA film. This resulted in a film coated with residual tung oil, showing antioxidant activity. Here, we report the first application of tung oil as a substrate for PHA production, introducing a high proportion of hydroxyhexanoate monomer into the terpolymer. Additionally, the residual tung oil was used as an antioxidant coating, resulting in the production of bioactive PHA, expanding the applicability to the medical field.

Oxidative stress originates from an elevated intracellular level of free oxygen radicals that cause lipid peroxidation, protein denaturation, DNA hydroxylation, and apoptosis, ultimately impairing cell viability. Antioxidants scavenge free radicals and reduce oxidative stress, which further helps to prevent cellular damage. Medicinal plants, fruits, and spices are the primary sources of antioxidants from time immemorial. In contrast to plants, microorganisms can be used as a source of antioxidants with the advantage of fast growth under controlled conditions. Further, microbe-based antioxidants are nontoxic, noncarcinogenic, and biodegradable as compared to synthetic antioxidants. The present review aims to summarize the current state of the research on the antioxidant activity of microorganisms including actinomycetes, bacteria, fungi, protozoa, microalgae, and yeast, which produce a variety of antioxidant compounds, i.e., carotenoids, polyphenols, vitamins, and sterol, etc. Special emphasis is given to the mechanisms and signaling pathways followed by antioxidants to scavenge Reactive Oxygen Species (ROS), especially for those antioxidant compounds that have been scarcely investigated so far.

Oxidative stress is an elevated intracellular level of free oxygen radicals that cause lipid peroxidation, protein denaturation, DNA hydroxylation, and apoptosis, ultimately negotiating cells viability. Antioxidants can scavenge such free radicals, thus reducing the oxidative stress and eventually prevent cellular damage. Medicinal plants, fruits, and spices remain the prioritized sources of antioxidants and antimicrobial properties since the time immemorial, but in contrast to plants, microorganisms can be grown at a faster rate under controlled conditions. They are non-toxic, non-carcinogenic, and biodegradable as compared to synthetic antioxidants. Microorganisms including actinomycetes, archaea, bacteria, protozoa, yeast, and fungi are auspicious source of vital bioactive compounds. The list comprises ample of bioactive components from microorganisms. One of them is bacteriocins, which are ribosomally synthesized antimicrobial peptides product of Eurotium sp., Streptomyces parvulus, S. thermophiles, Lactococcus lactis, etc. It has a great potential as next-generation antibiotics targeting the multiple-drug resistant pathogens. Pneumocandins are antifungal lipohexapeptides derived from the fungus Glarea lozoyensis, and inhibit 1,3-β-glucan synthase of the fungal cell wall and act as a precursor for the synthesis of caspofungin. It is widely used against invasive fungal infections and has been recently approved by the FDA. Taxol (paclitaxel), a chemotherapeutic drug derived from the bark of Taxus brevifolia can also be produced by endophytic fungi Taxomyces andreanae and Nodulisporium sylviforme. It is known to inhibit several fungi such as Pythium, Aphanomyces and Phytophthora. Hispidin and its derivate isolated from P. hispidus, reduce inducible nitric oxide synthase (iNOS) expression, obstruct the transcriptional activity of NF-κB, and also decrease the production of reactive oxygen species (ROS) in macrophages. Astaxanthin, known as an “aquatic” carotenoid produced by H. pluvialis, also has excellent ROS quenching activity. This study mainly focuses on fascinating antioxidant and antimicrobial compounds that have been scarcely investigated in microorganisms and discuss the promise and challenges of microorganisms as providers of health benefits.

Thin oxide coatings are attractive both for research and application as they possess good thermal and electrical resistance properties. In the recent time these coatings are commercially exploited because of good oxidation, wear, erosion resistance than metals even in high-temperature environments. Incorporation of different ceramic particles in organic coating is well studied and even commercialized as it incorporates the advantages of both inorganic and organic coating. Even nanosized silica was reported to be an alternative to chromate conversion coating. There are different techniques used to have ceramic coating on different surfaces including sol–gel, thermal spray, slurry, chemical vapor deposition, etc. Use of nano-SiO2 and TiO2-based coatings for superhydrophilicity and self-cleaning properties were also studied in recent years. Light-mediated antifungal and antibacterial properties of semiconductor oxides namely TiO2, ZnO also attracted the attention of researchers. In particular sol–gel based oxide (Al2O3, TiO2, ZrO2, and SiO2) coatings are of interest to develop different functional protective properties. Sol–gel-based coating attracted much attention in recent years as it can be used to formulate self-healing coating thus increasing the life of the material. In general sol–gel coating can have thickness from nanometer to micron level with high corrosion and erosion resistance. With this technique one can create transparent layer thus preserving the luster and aesthetic of the material with high corrosion protection. Hydrophobicity and self-cleaning properties are added advantages to corrosion protection and hence quite useful for outdoor applications like buildings, infrastructures, and solar cell. Sometime mixed oxide ceramic coatings serve much better than the single oxide coating. Inhibitor loaded oxide container-based self-healing coating inspired by the nature also discussed because of growing number of articles in this subject. Due to the growing interest in this subject area this chapter is compiled focusing on the oxide-based coatings in the specific light of corrosion protection, hydrophobic, superhydrophilic, and self-cleaning properties.

Ionic liquids (ILs) have been receiving much attention as solvents in various areas of biochemistry because of their various beneficial properties over the volatile solvents and ILs availability in myriad variants (perhaps as many as 108) owing to the possibility of paring one cation with several anions andvice-versaas well as formulations as zwitterions. Their potential as solvents lies in their tendency to offer both directional and non-directional forces toward a solute molecule. Because of these forces, ionic liquids easily undergo intermolecular interactions with a range of polar/non-polar solutes, including biomolecules such as proteins and DNA. The interaction of genomic species in aqueous/non-aqueous states assists in unraveling their structure and functioning, which have implications in various biomedical applications. The charge density of ionic liquids renders them hydrophilic and hydrophobic, which retain intact over long-range of temperatures. Their ability in stabilizing or destabilizing the 3D-structure of a protein or the double-helical structure of DNA has been assessed superior to the water and volatile organic solvents. The aptitude of an ion in influencing the structure and stability of a native protein depends on their ranking in the Hofmeister series. However, at several instances, a reverse Hofmeister ordering of ions and specific ion-solute interaction has been observed. The capability of an ionic liquid in terms of the tendency to promote the coiling/uncoiling of DNA structure is noted to rely on the basicity, electrostatic interaction, and hydrophobicity of the ionic liquid in question. Any change in the DNA's double-helical structure reflects a change in its melting temperature (Tm), compared to a standard buffer solution. These changes in DNA structure have implications in biosensor design and targeted drug-delivery in biomedical applications. In the current review, we have attempted to highlight various aspects of ionic liquids that influence the structure and properties of proteins and DNA. In short, the review will address the issues related to the origin and strength of intermolecular interactions, the effect of structural components, their nature, and the influence of temperature, pH, and additives on them.

The present investigation deals with the adsorptive removal of crude petroleum oil from the water surface using coconut oil-modified pinewood biochar. Biochar generated at higher pyrolysis temperature (700 °C) revealed higher fatty acid-binding efficiency responsible for the excellent hydrophobicity of the biochar. Fatty acids composition attached to the biochar produced at 700 °C was (mg g−1 BC) lauric acid (9.024), myristic acid (5.065), palmitic acid (2.769), capric acid (1.639), oleic acid (1.362), stearic acid (1.114), and linoleic acid (0.130). Simulation of the experimental adsorption data of pristine and modified pinewood biochar generated at 700 °C offered the best fit to pseudo-first-order kinetics (R2 > 0.97) and Langmuir isotherm model (R2 > 0.99) based on the highest regression coefficients. Consequently, the adsorption process was mainly driven by surface hydrophobic interactions including π-π electron-donor-acceptor between electron-rich (π-donor) polycyclic aromatic hydrocarbons from the crude oil and biochar (π-acceptor). A maximum adsorption capacity (Qmax) of 5.315 g g−1 was achieved by modified floating biochar within 60 min. Whereas the reusability testing revealed 49.39% and 51.40% was the adsorption efficiency of pristine and modified biochar at the fifth adsorption-desorption cycle.

In the present study, an exopolysaccharide (EPS)-producing bacterial strain was isolated from the Eastern Sea (Sokcho Beach) of South Korea and identified as Sphingobium yanoikuyae BBL01. Media optimization was performed using response surface design, and a yield of 2.63 ± 0.02 g/L EPS was achieved. Purified EPS produced using lactose as the main carbon source was analyzed by GC–MS and found to be composed of α-D-xylopyranose (28.6 ± 2.0%), β-D-glucopyranose (21.0 ± 1.6%), α-D-mannopyranose (18.5 ± 1.2%), β- d -mannopyranose (13.1 ± 1.4%), β-D-xylopyranose (10.2 ± 2.1%), α- d -talopyranose (5.9 ± 1.1%), and β- d -galacturonic acid (2.43 ± 0.8%). Interestingly, different carbon sources (glucose, galactose, glycerol, lactose, sucrose, and xylose) showed no effect on EPS monomer composition, with a slight change in the mass percentage of various monosaccharides. Purified EPS was stable up to 233 °C, indicating its possible suitability as a thickening and gelling agent for food-related applications. EPS also showed considerable emulsifying, flocculating, free-radical scavenging, and metal-complexion activity, suggesting various biotechnological applications.

Rapid development in the printing and dying industry produces large amounts of wastewater, and its discharge in the environment causes pollution. Keeping in view the carcinogenic and mutagenic properties of various dyes, it is important to treat dyed wastewater. Maple leaf biochars were produced at different pyrolysis temperatures, i.e., 350 &deg, C, 550 &deg, C, and 750 &deg, C, characterized for physicochemical properties and used for the removal of cationic (methylene blue (MB)) and anionic dye (congo red (CR)). Response surface methodology (RSM) using three variables, i.e., pH (4, 7, and 10), pyrolysis temperature (350 &deg, C), and adsorption temperature (20 &deg, C, 30 &deg, C, and 40 &deg, C), was designed to find the optimum condition for dyes removal. X-ray diffraction (XRD) analysis showed an increase in CaCO3 crystallinity and a decrease in MgCO3 crystallinity with the increase of pyrolysis temperature. RSM design results showed that maple biochar showed maximum adsorption capacity for cationic dye at higher pH (9&ndash, 10) and for anionic dye at pH 4-6, respectively. Under the selected condition of pH 7 and an adsorption temperature of 30 &deg, C, biochar MB550 was able to remove MB and CR by 68% and 74%, respectively, from dye mixtures. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses showed that MB550 was able to remove both dyes simultaneously from the aqueous mixtures.

Pipecolic acid, a non-proteinogenic amino acid, is a metabolite in lysine metabolism and a key chiral precursor in local anesthesia and macrolide antibiotics. To replace the environmentally unfriendly chemical production or preparation procedure of pipecolic acid, many biological synthetic routes have been studied for a long time. Among them, synthesis by lysine cyclodeaminase (LCD), encoded by pipA, has several advantages, including stability of enzyme activity and NAD+ self-regeneration. Thus, we selected this enzyme for pipecolic acid biosynthesis in a whole-cell bioconversion. To construct a robust pipecolic acid production system, we investigated important conditions including expression vector, strain, culture conditions, and other reaction parameters. The most important factor was the introduction of multiple pipA genes into the whole-cell system. As a result, we produced 724 mM pipecolic acid (72.4 % conversion), and the productivity was 0.78 g/L/h from 1 M l-lysine after 5 days. This is the highest production reported to date.

Methicillin-resistant Staphylococcus aureus (MRSA) strains are distinct from general Staphylococcus strains with respect to the composition of the membrane, ability to form a thicker biofilm, and, importantly, ability to modify the target of antibiotics to evade their activity. The agr gene is an accessory global regulator of gram-positive bacteria that governs virulence or resistant mechanisms and is therefore an important target for the control of resistant strains. However, the mechanism by which agr impacts factors affecting resistance to β-lactam antibiotics remains unclear. In the present study, we found an Δagr mutant strain with higher resistance to high concentrations of b-lactam antibiotics such as oxacillin and ampicillin. To determine the influence of variation in the microenvironment of cells between the parental and mutant strains, fatty acid analysis of the supernatant, total lipids, and phospholipid fatty acids were compared. The Δagr mutant strain tended to produce fewer fatty acids and retained lower amounts of C16, C18 fatty acids in the supernatant. Phospholipid analysis showed a dramatic increase in the hydrophobic longer-chain fatty acids in the membranes. To target these differences in fatty acid distribution and membrane composition, we applied several surfactants and found that sorbitan trioleate (Span85) had a synergistic effect with oxacillin by decreasing biofilm formation and growth. These findings indicate that agr suppression allows for MRSA to antagonize antibiotics via several changes, including constant expression of mecA, fatty acid metabolism and distribution, and biofilm thickening, resulting in a strain with higher resistance to β-lactam antibiotics.

Background: Intravenous iron is associated with oxidative stress, and very few studies have assessed change in oxidative stress markers post infusion. Objectives: The study aimed to measure the change in levels of hemoglobin (Hb), serum ferritin, and select oxidative stress markers (malondialdehyde [MDA], superoxide dismutase [SOD], and ferric reducing ability of plasma [FRAP]) 4 weeks following the administration of intravenous iron sucrose (IVIS) among moderately anemic pregnant women who were attending a secondary-level health-care facility, Haryana, North India. Methods: An observational study was conducted (May 2016 to Jan 2018) among pregnant women receiving intravenous iron sucrose i.e., IVIS (300 mg per dose) diluted in 300 mL of normal saline over 20–45 min and were followed up for a period of 4 weeks after the last dose of IVIS (end line). The study outcomes were measured in the levels of Hb, serum ferritin, MDA, SOD, and FRAP from the baseline to the end line. Results: The mean (95% confidence interval) change in the Hb and serum ferritin level 4 weeks after the last dose of IVIS was an increase of 2.5 (2.1–3.0) g/dL (P < 0.001) and 63.0 (44.7–81.3) ng/mL (P < 0.001), respectively. There were no significant changes (baseline to end line) in mean (standard deviation [SD]) MDA level and mean (SD) FRAP level. The mean (SD) SOD level declined significantly (2.2 [0.4] U/mL to 1.6 [0.5] U/mL [P < 0.001]). No life-threatening adverse events were encountered during the study. Conclusion: IVIS was well tolerated and effective in treating moderate anemia in pregnancy. Body iron store was replenished following IVIS administration. There was no increase in oxidative stress following IVIS therapy.

Bacteria from the genus Halomonas hold promise in biotechnology as sources of salt-tolerant enzymes, biosurfactants, biopolymers, osmolytes, and as actors in bioremediation processes. In a previous work, we have identified Halomonas socia strain CKY01 having various hydrolase activities. Here, we aimed to study the survival strategies of marine bacteria. A deep genome sequencing study of H. socia CKY01 has revealed 4627 genes reaching 4,753,299 bp with 64 % of GC content. This strain produced polyhydroxybutyrate (PHB) having one gene clusters having phaC and phasin, and it has several genes responsible for the uptake, synthesis, and transport of the osmolytes such as betaine, choline, ectoine, carnitine, and proline in the bacterial genome. The addition of 60 mM glutamate, 60 mM proline and 60 mM ectoine enhanced growth 300.8 %, 294.2 % and 235.0 %, respectively, under 10 % saline conditions. In particular, ectoine and proline increased salt resistance and allowed cells to survive in more than 15 % NaCl. By combining experimental and genome sequencing data, we have investigated the importance of osmolytes on the survival of this Halomonas strain.

MRSA is Methicillin-resistantStaphylococcus aureusand they are widespread and making trouble in treatment in communities and surgical areas. MRSA have been adapted to antibiotics so that they can block the access of antibiotics physically or chemically deactivate it or modify the precursor of the target. Flavonoids are secondary metabolites which are naturally produced by plant or fungus and they are acting generally as pigment, quorum sensing molecules, antibiotics to other competitive microorganisms. Their natural origins and multiple activities have drawn much attention to be developed as the potential drugs since flavonoids could be a good candidate to overcome antibiotic resistant bacteria. Among various flavonoids, we found out naringenin has antibacterial activity on MRSA and Δagrmutants which are more resistance than MRSA to beta-lactam antibiotics by decreasing biofilm formation dramatically and decreasing the secretion of fatty acid. It also showed high synergetic activity with oxacillin to both antibacterial activity and biofilm inhibition. Considering the number of flavonoids, our experiments expand the possibility of the use of flavonoids to MRSA.