bluuebunny/crossref_metadata_2025 huggingface dataset:
Wastewater from the Edible Oil Industry as a Potential Source of Lipase- and Surfactant-Producing Actinobacteria
Authors: Welz Pamela , Swanepoel Gustav , Weels Shandré , Le Roes-Hill Marilize
Published: September 2021

Wastewaters generated from various stages of edible oil production in a canola processing facility were collected with the aim of determining the presence of lipase-producing actinobacteria of potential industrial significance. The high chemical oxygen demand (COD) readings (up to 86,700 mg L−1 in some samples) indicated that the wastewater exhibited the nutritional potential to support bacterial growth. A novel approach was developed for the isolation of metagenomic DNA from the oil-rich wastewater samples. Microbiota analysis of the buffer tank and refinery condensate tank wastewater samples showed a dominance of Cutibacterium acnes subsp. defendens, followed by a limited number of other actinobacterial genera, indicating the presence of a highly specialized actinobacterial population. Cultured isolates with typical actinobacterial morphology were analyzed for their ability to produce lipases and biosurfactants. Two strains, designated as BT3 and BT4, exhibited the highest lipase production levels when grown in the presence of tributyrin and olive oil (1.39 U mg−1 crude protein and 0.8 U mg−1 crude protein, respectively) and were subsequently definitively identified by genome sequencing to be related to Streptomyces albidoflavus. Cultivation of the strains in media containing different types of oils did not markedly increase the level of enzyme production, with the exception of strain BT4 (1.0 U mg−1 crude protein in the presence of peanut oil). Genome sequencing of the two strains, BT3 and BT4, revealed the presence of a range of lipase and esterase genes that may be involved in the production of the enzymes detected in this study. The presence of gene clusters involved in the production of biosurfactants were also detected, notably moreso in strain BT3 than BT4.
Comparative Genomics and Specific Functional Characteristics Analysis of Lactobacillus acidophilus
Authors: Huang Zheng , Zhou Xingya , Stanton Catherine , Ross Reynolds Paul , Zhao Jianxin , Zhang Hao , Yang Bo , Chen Wei
Published: September 2021

Lactobacillus acidophilus is a common kind of lactic acid bacteria usually found in the human gastrointestinal tract, oral cavity, vagina, and various fermented foods. At present, many studies have focused on the probiotic function and industrial application of L. acidophilus. Additionally, dozens of L. acidophilus strains have been genome sequenced, but there has been no research to compare them at the genomic level. In this study, 46 strains of L. acidophilus were performed comparative analyses to explore their genetic diversity. The results showed that all the L. acidophilus strains were divided into two clusters based on ANI values, phylogenetic analysis and whole genome comparison, due to the difference of their predicted gene composition of bacteriocin operon, CRISPR-Cas systems and prophages mainly. Additionally, L. acidophilus was a pan-genome open species with a difference in carbohydrates utilization, antibiotic resistance, EPS operon, surface layer protein operon and other functional gene composition. This work provides a better understanding of L. acidophilus from a genetic perspective, and offers a frame for the biotechnological potentiality of this species.
Composition and Corrosivity of Extracellular Polymeric Substances from the Hydrocarbon-Degrading Sulfate-Reducing Bacterium Desulfoglaeba alkanexedens ALDC
Authors: Davidova Irene A. , Lenhart Tiffany R. , Nanny Mark A. , Suflita Joseph M.
Published: September 2021

Sulfate-reducing bacteria (SRB) often exist as cell aggregates and in biofilms surrounded by a matrix of extracellular polymeric substances (EPSs). The chemical composition of EPSs may facilitate hydrophobic substrate biodegradation and promote microbial influenced corrosion (MIC). Although EPSs from non-hydrocarbon-degrading SRB have been studied; the chemical composition of EPSs from hydrocarbon-degrading SRBs has not been reported. The isolated EPSs from the sulfate-reducing alkane-degrading bacterium Desulfoglaeba alkanexedens ALDC was characterized with scanning and fluorescent microscopy, nuclear magnetic resonance spectroscopy (NMR), and by colorimetric chemical assays. Specific fluorescent staining and 1H NMR spectroscopy revealed that the fundamental chemical structure of the EPS produced by D. alkanexedens is composed of pyranose polysaccharide and cyclopentanone in a 2:1 ratio. NMR analyses indicated that the pyranose ring structure is bonded by 1,4 connections with the cyclopentanone directly bonded to one pyranose ring. The presence of cyclopentanone presumably increases the hydrophobicity of the EPS that may facilitate the accessibility of hydrocarbon substrates to aggregating cells or cells in a biofilm. Weight loss and iron dissolution experiments demonstrated that the EPS did not contribute to the corrosivity of D. alkanexedens cells.
Risk of Hemolytic Uremic Syndrome Related to Treatment of Escherichia coli O157 Infection with Different Antimicrobial Classes
Authors: Mody Rajal K. , Hoekstra Robert M. , Scott Magdalena Kendall , Dunn John , Smith Kirk , Tobin-D’Angelo Melissa , Shiferaw Beletshachew , Wymore Katie , Clogher Paula , Palmer Amanda , Comstock Nicole , Burzlaff Kari , Lathrop Sarah , Hurd Sharon , Griffin Patricia M.
Published: September 2021

Treatment of Shiga toxin-producing Escherichia coli O157 (O157) diarrhea with antimicrobials might alter the risk of hemolytic uremic syndrome (HUS). However, full characterization of which antimicrobials might affect risk is lacking, particularly among adults. To inform clinical management, we conducted a case-control study of residents of the FoodNet surveillance areas with O157 diarrhea during a 4-year period to assess antimicrobial class-specific associations with HUS among persons with O157 diarrhea. We collected data from medical records and patient interviews. We measured associations between treatment with agents in specific antimicrobial classes during the first week of diarrhea and development of HUS, adjusting for age and illness severity. We enrolled 1308 patients; 102 (7.8%) developed confirmed HUS. Antimicrobial treatment varied by age: <5 years (12.6%), 5–14 (11.5%), 15–39 (45.4%), ≥40 (53.4%). Persons treated with a β-lactam had higher odds of developing HUS (OR 2.80, CI 1.14–6.89). None of the few persons treated with a macrolide developed HUS, but the protective association was not statistically significant. Exposure to “any antimicrobial” was not associated with increased odds of HUS. Our findings confirm the risk of β-lactams among children with O157 diarrhea and extends it to adults. We observed a high frequency of inappropriate antimicrobial treatment among adults. Our data suggest that antimicrobial classes differ in the magnitude of risk for persons with O157 diarrhea.
A Mouse Model for Studying Post-Acute Arthritis of Chikungunya
Authors: Chang Aileen Y. , Tritsch Sarah R. , Porzucek Abigail J. , Schwartz Arnold M. , Seyler-Schmidt Margaux , Glass Arielle , Latham Patricia S. , Reid St. Patrick , Simon Gary L. , Mores Christopher N.
Published: September 2021

Chikungunya virus (CHIKV) was introduced to the Americas in 2013, causing two million infections across over thirty countries. CHIKV causes a chronic debilitating arthritis in one fourth of infected individuals and currently evidence-based targeted therapies for the treatment of CHIKV arthritis are lacking. Multiple mouse models of chikungunya have been developed to study acute CHIKV infection. In humans, post-CHIKV arthritis may persist for months to years after viremia from a CHIKV infection has resolved. Therefore, the development of a mouse model of post-acute arthritis of chikungunya may facilitate the study of potential novel therapeutics for this arthritis. In this article we describe the development of a wild-type immunocompetent C57BL/6 mouse model for post-acute arthritis of chikungunya, including a histologic inflammation scoring system, as well as suggestions for how this mouse model may be used to examine the efficacy of novel therapies for CHIKV arthritis.
Geochemical Characteristics, Palaeoenvironment and Provenance of Uranium-Bearing Sandstone in the Sifangtai Formation, Northern Songliao Basin, Northeast China
Authors: Li Yan , Nie Feng-Jun , Jia Li-Cheng , Lu Sheng-Jun , Yan Zhao-Bin
Published: September 2021

During the Cretaceous period of the northern Songliao Basin (northeast of China), a 100 m thick layer of fluvial-phase sandstone (Sifangtai Formation) with uranium potential was widely deposited, but its geochemical characteristics, paleoenvironment, and provenance remain unknown. This research proposes a new set of relevant geochemical data for sandstones to investigate their paleoenvironment, provenance and tectonic setting. The results revealed that: (1) The sandstone of the Sifangtai Formation was dominated by feldspar lithic sandstone. Geochemical signatures demonstrate that these sandstones have a high silicon content (SiO2 = 68.30~83.60 wt%) and total alkali content, but are poor in magnesium and calcium. They are also enriched in Rb, Th, U, K and LREE, and depleted HFSE (e.g., Nb, Ta), with crustal magmatic source. (2) The paleoclimate discriminant indicated that the rocks of the Sifangtai Formation might that the climate of Sifangtai Formation is semi-arid, and the chemical weathering of the source rocks is weak under the semi-arid climate environment. (3) The combination of element Sr/Ba, 100 MgO/Al2O3 and the combination of v/v + Ni, V/Cr, Ni/Co, and Sr/Cu indicated that the paleo-water medium was deposited in an oxygen-rich freshwater environment when the Sifangtai Formation was deposited. (4) The discriminate diagrams showed that almost all the sandstones of the Sifangtai Formation fell in the range of the active continental margin, indicating that the source area of the sandstones of Sifangtai Formations is an active continental margin tectonic environment, and the source is a felsic rock developed in the Xiaoxing’an Ridge and Zhangguangcailing area.
Sample Preparation and Diagnostic Methods for a Variety of Settings: A Comprehensive Review
Authors: Nichols Zach E. , Geddes Chris D.
Published: September 2021

Sample preparation is an essential step for nearly every type of biochemical analysis in use today. Among the most important of these analyses is the diagnosis of diseases, since their treatment may rely greatly on time and, in the case of infectious diseases, containing their spread within a population to prevent outbreaks. To address this, many different methods have been developed for use in the wide variety of settings for which they are needed. In this work, we have reviewed the literature and report on a broad range of methods that have been developed in recent years and their applications to point-of-care (POC), high-throughput screening, and low-resource and traditional clinical settings for diagnosis, including some of those that were developed in response to the coronavirus disease 2019 (COVID-19) pandemic. In addition to covering alternative approaches and improvements to traditional sample preparation techniques such as extractions and separations, techniques that have been developed with focuses on integration with smart devices, laboratory automation, and biosensors are also discussed.
Synthesis of Biologically Relevant 1,2,3- and 1,3,4-Triazoles: From Classical Pathway to Green Chemistry
Authors: Gonnet Lori , Baron Michel , Baltas Michel
Published: September 2021

Green Chemistry has become in the last two decades an increasing part of research interest. Nonconventional «green» sources for chemical reactions include micro-wave, mechanical mixing, visible light and ultrasound. 1,2,3-triazoles have important applications in pharmaceutical chemistry while their 1,2,4 counterparts are developed to a lesser extent. In the review presented here we will focus on synthesis of 1,2,3 and 1,2,4-triazole systems by means of classical and « green chemistry » conditions involving ultrasound chemistry and mechanochemistry. The focus will be on compounds/scaffolds that possess biological/pharmacophoric properties. Finally, we will also present the formal cycloreversion of 1,2,3-triazole compounds under mechanical forces and its potential use in biological systems.
Targeting Monoacylglycerol Lipase in Pursuit of Therapies for Neurological and Neurodegenerative Diseases
Authors: Zanfirescu Anca , Ungurianu Anca , Mihai Dragos Paul , Radulescu Denise , Nitulescu George Mihai
Published: September 2021

Neurological and neurodegenerative diseases are debilitating conditions, and frequently lack an effective treatment. Monoacylglycerol lipase (MAGL) is a key enzyme involved in the metabolism of 2-AG (2-arachidonoylglycerol), a neuroprotective endocannabinoid intimately linked to the generation of pro- and anti-inflammatory molecules. Consequently, synthesizing selective MAGL inhibitors has become a focus point in drug design and development. The purpose of this review was to summarize the diverse synthetic scaffolds of MAGL inhibitors concerning their potency, mechanisms of action and potential therapeutic applications, focusing on the results of studies published in the past five years. The main irreversible inhibitors identified were derivatives of hexafluoroisopropyl alcohol carbamates, glycol carbamates, azetidone triazole ureas and benzisothiazolinone, whereas the most promising reversible inhibitors were derivatives of salicylketoxime, piperidine, pyrrolidone and azetidinyl amides. We reviewed the results of in-depth chemical, mechanistic and computational studies on MAGL inhibitors, in addition to the results of in vitro findings concerning selectivity and potency of inhibitors, using the half maximal inhibitory concentration (IC50) as an indicator of their effect on MAGL. Further, for highlighting the potential usefulness of highly selective and effective inhibitors, we examined the preclinical in vivo reports regarding the promising therapeutic applications of MAGL pharmacological inhibition.
π–π Noncovalent Interaction Involving 1,2,4- and 1,3,4-Oxadiazole Systems: The Combined Experimental, Theoretical, and Database Study
Authors: Baykov Sergey V. , Mikherdov Alexander S. , Novikov Alexander S. , Geyl Kirill K. , Tarasenko Marina V. , Gureev Maxim A. , Boyarskiy Vadim P.
Published: September 2021

A series of N-pyridyl ureas bearing 1,2,4- (1a, 2a, and 3a) and 1,3,4-oxadiazole moiety (1b, 2b, 3b) was prepared and characterized by HRMS, 1H and 13C NMR spectroscopy, as well as X-ray diffraction. The inspection of the crystal structures of (1–3)a,b and the Hirshfeld surface analysis made possible the recognition of the (oxadiazole)···(pyridine) and (oxadiazole)···(oxadiazole) interactions. The presence of these interactions was confirmed theoretically by DFT calculations, including NCI analysis for experimentally determined crystal structures as well as QTAIM analysis for optimized equilibrium structures. The preformed database survey allowed the verification of additional examples of relevant (oxadiazole)···π interactions both in Cambridge Structural Database and in Protein Data Bank, including the cocrystal of commercial anti-HIV drug Raltegravir.
Sialyltransferase Inhibitors for the Treatment of Cancer Metastasis: Current Challenges and Future Perspectives
Authors: Perez Ser John Lynon P. , Fu Chih-Wei , Li Wen-Shan
Published: September 2021

Potent, cell-permeable, and subtype-selective sialyltransferase inhibitors represent an attractive family of substances that can potentially be used for the clinical treatment of cancer metastasis. These substances operate by specifically inhibiting sialyltransferase-mediated hypersialylation of cell surface glycoproteins or glycolipids, which then blocks the sialic acid recognition pathway and leads to deterioration of cell motility and invasion. A vast amount of evidence for the in vitro and in vivo effects of sialyltransferase inhibition or knockdown on tumor progression and tumor cell metastasis or colonization has been accumulated over the past decades. In this regard, this review comprehensively discusses the results of studies that have led to the recent discovery and development of sialyltransferase inhibitors, their potential biomedical applications in the treatment of cancer metastasis, and their current limitations and future opportunities.
Interaction of (+)-Strebloside and Its Derivatives with Na+/K+-ATPase and Other Targets
Authors: Ren Yulin , Wu Sijin , Chen Sijie , Burdette Joanna E. , Cheng Xiaolin , Kinghorn A. Douglas
Published: September 2021

Docking profiles for (+)-strebloside, a cytotoxic cardiac glycoside identified from Streblus asper, and some of its derivatives and Na+/K+-ATPase have been investigated. In addition, binding between (+)-strebloside and its aglycone, strophanthidin, and several of their other molecular targets, including FIH-1, HDAC, KEAP1 and MDM2 (negative regulators of Nrf2 and p53, respectively), NF-κB, and PI3K and Akt1, have been inspected and compared with those for digoxin and its aglycone, digoxigenin. The results showed that (+)-strebloside, digoxin, and their aglycones bind to KEAP1 and MDM2, while (+)-strebloside, strophanthidin, and digoxigenin dock to the active pocket of PI3K, and (+)-strebloside and digoxin interact with FIH-1. Thus, these cardiac glycosides could directly target HIF-1, Nrf2, and p53 protein–protein interactions, Na+/K+-ATPase, and PI3K to mediate their antitumor activity. Overall, (+)-strebloside seems more promising than digoxin for the development of potential anticancer agents.
In Vitro Phenotypic Activity and In Silico Analysis of Natural Products from Brazilian Biodiversity on Trypanosoma cruzi
Authors: Peres Raiza B. , Fiuza Ludmila F. de A. , da Silva Patrícia B. , Batista Marcos M. , Camillo Flávia da C. , Marques André M. , de C. Brito Lavínia , Figueiredo Maria R. , Soeiro Maria de N. C.
Published: September 2021

Chagas disease (CD) affects more than 6 million people worldwide. The available treatment is far from ideal, creating a demand for new alternative therapies. Botanical diversity provides a wide range of novel potential therapeutic scaffolds. Presently, our aim was to evaluate the mammalian host toxicity and anti-Trypanosoma cruzi activity of botanic natural products including extracts, fractions and purified compounds obtained from Brazilian flora. In this study, 36 samples of extracts and fractions and eight pure compounds obtained from seven plant species were evaluated. The fraction dichloromethane from Aureliana fasciculata var. fasciculata (AFfPD) and the crude extract of Piper tectoniifolium (PTFrE) showed promising trypanosomicidal activity. AFfPD and PTFrE presented EC50 values 10.7 ± 2.8 μg/mL and 12.85 ± 1.52 μg/mL against intracellular forms (Tulahuen strain), respectively. Additionally, both were active upon bloodstream trypomastigotes (Y strain), exhibiting EC50 2.2 ± 1.0 μg/mL and 38.8 ± 2.1 μg/mL for AFfPD and PTFrE, respectively. Importantly, AFfPD is about five-fold more potent than Benznidazole (Bz), the reference drug for CD, also reaching lower EC90 value (7.92 ± 2.2 μg/mL) as compared to Bz (23.3 ± 0.6 μg/mL). Besides, anti-parasitic effect of eight purified botanic substances was also investigated. Aurelianolide A and B (compounds 1 and 2) from A. fasciculata and compound 8 from P. tuberculatum displayed the best trypanosomicidal effect. Compounds 1, 2 and 8 showed EC50 of 4.6 ± 1.3 μM, 1.6 ± 0.4 μM and 8.1 ± 0.9 μM, respectively against intracellular forms. In addition, in silico analysis of these three biomolecules was performed to predict parameters of absorption, distribution, metabolism and excretion. The studied compounds presented similar ADMET profile as Bz, without presenting mutagenicity and hepatotoxicity aspects as predicted for Bz. Our findings indicate that these natural products have promising anti-T. cruzi effect and may represent new scaffolds for future lead optimization.
Design, Synthesis, and Biochemical Evaluation of New Triazole Derivatives as Aurora-A Kinase Inhibitors
Authors: Abdullah Omeima
Published: September 2021

Aurora-A kinase, a key mitosis regulator, is expressed in a cell cycle-dependent manner and has an essential role in maintaining chromosomal stability and the normal progression of the cell through mitosis. Aurora-A kinase is overexpressed in many malignant solid tumors, such as breast, ovarian, colon, and pancreatic cancers. Thus, inhibiting Aurora-A kinase activity is a promising approach for cancer treatment. Here, new triazole derivatives were designed as bioisosteric analogues of the known inhibitor JNJ-7706621. The new compounds showed interesting inhibitory activity against Aurora-A kinase, as attested by IC50s in the low to submicromolar range.
Involvement of DPY19L3 in Myogenic Differentiation of C2C12 Myoblasts
Authors: Mori Kento , Sun Hongkai , Miura Kazuki , Simizu Siro
Published: September 2021

DPY19L3 has been identified as a C-mannosyltransferase for thrombospondin type-1 repeat domain-containing proteins. In this study, we focused on the role of DPY19L3 in the myogenic differentiation of C2C12 mouse myoblast cells. We carried out DPY19L3 gene depletion using the CRISPR/Cas9 system. The result showed that these DPY19L3-knockout cells could not be induced for differentiation. Moreover, the phosphorylation levels of MEK/ERK and p70S6K were suppressed in the DPY19L3-knockout cells compared with that of parent cells, suggesting that the protein(s) that is(are) DPY19L3-mediated C-mannosylated and regulate(s) MEK/ERK or p70S6K signaling is(are) required for the differentiation.
The Use of Single Drop Microextraction and Field Amplified Sample Injection for CZE Determination of Homocysteine Thiolactone in Urine
Authors: Purgat Krystian , Kośka Izabella , Kubalczyk Paweł
Published: September 2021

Two cheap, simple and reproducible methods for the electrophoretic determination of homocysteine thiolactone (HTL) in human urine have been developed and validated. The first method utilizes off-line single drop microextraction (SDME), whereas the second one uses off-line SDME in combination with field amplified sample injection (FASI). The off-line SDME protocol consists of the following steps: urine dilution with 0.2 mol/L, pH 8.2 phosphate buffer (1:2, v/v), chloroform addition, drop formation and extraction of HTL. The pre-concentration of HTL inside a separation capillary was performed by FASI. For sample separation, the 0.1 mol/L pH 4.75 phosphate buffer served as the background electrolyte, and HTL was detected at 240 nm. A standard fused-silica capillary (effective length 55.5 cm, 75 μm id) and a separation voltage of 21 kV (~99 μA) were used. Electrophoretic separation was completed within 7 min, whereas the LOD and LOQ for HTL were 0.04 and 0.1 μmol/L urine, respectively. The calibration curve in urine was linear in the range of 0.1–0.5 μmol/L, with R2 = 0.9991. The relative standard deviation of the points of the calibration curve varied from 2.4% to 14.9%. The intra- and inter-day precision and recovery were 6.4–10.2% (average 6.0% and 6.7%) and 94.9–102.7% (average 99.7% and 99.5%), respectively. The analytical procedure was successfully applied to the analysis of spiked urine samples obtained from apparently healthy volunteers.
A Simple One-Step Modification of Shrimp Shell for the Efficient Adsorption and Desorption of Copper Ions
Authors: Liu Changkun , Wen Hui , Chen Kaili , Chen Yanni
Published: September 2021

Removing toxic heavy metal species from aqueous solutions is a point of concern in our society. In this paper, a promising biomass adsorbent, the modified waste shrimp shell (MS), for Cu (II) removal was successfully prepared using a facile and simple one-step modification, making it possible to achieve high-efficiency recycling of the waste NaOH solution as the modification agent. The outcome shows that with the continuous increase in pH, temperature and ion concentration, the adsorption effect of MS on Cu (II) can also be continuously improved. Adsorption isotherm and adsorption kinetics were fitted with the Langmuir isotherm model and the pseudo-second-order model, respectively, and the maximum adsorption capacity of Cu (II) as obtained from the Langmuir isotherm model fitting reached 1.04 mmol/g. The systematic desorption results indicated that the desorption rate of Cu (II) in the MS could reach 100% within 6 min, where HNO3 is used as the desorption agent. Moreover, experiments have proven that after five successive recycles of NaOH as a modifier, the adsorption capacity of MS on Cu (II) was efficient and stable, maintaining tendency in 0.83–0.85 mmol/g, which shows that waste NaOH solution can be used as a modification agent in the preparation of waste shrimp shell adsorbent, such as waste NaOH solution produced in industrial production, thereby making it possible to turn waste into renewable resources and providing a new way to recycle resources.
Electrophilically Activated Nitroalkanes in Double Annulation of [1,2,4]Triazolo[4,3-a]quinolines and 1,3,4-Oxadiazole Rings
Authors: Aksenov Alexander V. , Kirilov Nikita K. , Aksenov Nicolai A. , Aksenov Dmitrii A. , Sorokina Elena A. , Lower Carolyn , Rubin Michael
Published: September 2021

Nitroalkanes activated with polyphosphoric acid could serve as efficient electrophiles in reactions with amines and hydrazines, enabling various cascade transformations toward heterocyclic systems. This strategy was developed for an innovative synthetic protocol employing simultaneous or sequential annulation of two different heterocyclic cores, affording [1,2,4]triazolo[4,3-a]quinolines with 1,3,4-oxadiazole substituents.
Controlling the Substrate Specificity of an Enzyme through Structural Flexibility by Varying the Salt-Bridge Density
Authors: Huang Juan , Xu Qin , Liu Zhuo , Jain Nitin , Tyagi Madhusudan , Wei Dong-Qing , Hong Liang
Published: September 2021

Many enzymes, particularly in one single family, with highly conserved structures and folds exhibit rather distinct substrate specificities. The underlying mechanism remains elusive, the resolution of which is of great importance for biochemistry, biophysics, and bioengineering. Here, we performed a neutron scattering experiment and molecular dynamics (MD) simulations on two structurally similar CYP450 proteins; CYP101 primarily catalyzes one type of ligands, then CYP2C9 can catalyze a large range of substrates. We demonstrated that it is the high density of salt bridges in CYP101 that reduces its structural flexibility, which controls the ligand access channel and the fluctuation of the catalytic pocket, thus restricting its selection on substrates. Moreover, we performed MD simulations on 146 different kinds of CYP450 proteins, spanning distinct biological categories including Fungi, Archaea, Bacteria, Protista, Animalia, and Plantae, and found the above mechanism generally valid. We demonstrated that, by fine changes of chemistry (salt-bridge density), the CYP450 superfamily can vary the structural flexibility of its member proteins among different biological categories, and thus differentiate their substrate specificities to meet the specific biological needs. As this mechanism is well-controllable and easy to be implemented, we expect it to be generally applicable in future enzymatic engineering to develop proteins of desired substrate specificities.
Exploring the Bile Stress Response of Lactobacillus mucosae LM1 through Exoproteome Analysis
Authors: Bagon Bernadette B. , Oh Ju Kyoung , Valeriano Valerie Diane V. , Pajarillo Edward Alain B. , Kang Dae-Kyung
Published: September 2021

Lactobacillus sp. have long been studied for their great potential in probiotic applications. Recently, proteomics analysis has become a useful tool for studies on potential lactobacilli probiotics. Specifically, proteomics has helped determine and describe the physiological changes that lactic acid bacteria undergo in specific conditions, especially in the host gut. In particular, the extracellular proteome, or exoproteome, of lactobacilli contains proteins specific to host– or environment–microbe interactions. Using gel-free, label-free ultra-high performance liquid chromatography tandem mass spectrometry, we explored the exoproteome of the probiotic candidate Lactobacillus mucosae LM1 subjected to bile treatment, to determine the proteins it may use against bile stress in the gut. Bile stress increased the size of the LM1 exoproteome, secreting ribosomal proteins (50S ribosomal protein L27 and L16) and metabolic proteins (lactate dehydrogenase, phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase and pyruvate dehydrogenases, among others) that might have moonlighting functions in the LM1 bile stress response. Interestingly, membrane-associated proteins (transporters, peptidase, ligase and cell division protein ftsH) were among the key proteins whose secretion were induced by the LM1 bile stress response. These specific proteins from LM1 exoproteome will be useful in observing the proposed bile response mechanisms via in vitro experiments. Our data also reveal the possible beneficial effects of LM1 to the host gut.
Supercritical Carbon Dioxide Extraction of Four Medicinal Mediterranean Plants: Investigation of Chemical Composition and Antioxidant Activity
Authors: Čižmek Lara , Bavcon Kralj Mojca , Čož-Rakovac Rozelindra , Mazur Dmitrii , Ul’yanovskii Nikolay , Likon Marko , Trebše Polonca
Published: September 2021

With everyday advances in the field of pharmaceuticals, medicinal plants have high priority regarding the introduction of novel synthetic compounds by the usage of environmentally friendly extraction technologies. Herein, a supercritical CO2 extraction method was implemented in the analysis of four plants (chamomile, St. John’s wort, yarrow, and curry plant) after which the non-targeted analysis of the chemical composition, phenolic content, and antioxidant activity was evaluated. The extraction yield was the highest for the chamomile (5%), while moderate yields were obtained for the other three plants. The chemical composition analyzed by gas chromatography-high-resolution mass spectrometry (GC-HRMS) and liquid chromatography-high-resolution mass spectrometry (LC-HRMS) demonstrated extraction of diverse compounds including terpenes and terpenoids, fatty acids, flavonoids and coumarins, functionalized phytosterols, and polyphenols. Voltammetry of microfilm immobilized on a glassy carbon electrode using square-wave voltammetry (SWV) was applied in the analysis of extracts. It was found that antioxidant activity obtained by SWV correlates well to 1,1-diphenyl-2-picrylhidrazine (DPPH) radical assay (R2 = 0.818) and ferric reducing antioxidant power (FRAP) assay (R2 = 0.640), but not to the total phenolic content (R2 = 0.092). Effective results were obtained in terms of activity showing the potential usage of supercritical CO2 extraction to acquire bioactive compounds of interest.
Highly Efficient Micro-Scale Liquid-Liquid In-Flow Extraction of 99mTc from Molybdenum
Authors: Martini Petra , Uccelli Licia , Duatti Adriano , Marvelli Lorenza , Esposito Juan , Boschi Alessandra
Published: September 2021

The trend to achieve even more compact-sized systems is leading to the development of micro-scale reactors (lab-on-chip) in the field of radiochemical separation and radiopharmaceutical production. Technetium-99m extraction from both high and low specific activity molybdenum could be simply performed by MEK-driven solvent extraction if it were not for unpractical automation. The aim of this work is to develop a solvent extraction and separation process of technetium from molybdenum in a micro-scale in-flow chemistry regime with the aid of a capillary loop and a membrane-based separator, respectively. The developed system is able to extract and separate quantitatively and selectively (91.0 ± 1.8% decay corrected) the [99mTc]TcO4Na in about 20 min, by using a ZAIPUT separator device. In conclusion, we demonstrated for the first time in our knowledge the high efficiency of a MEK-based solvent extraction process of 99mTc from a molybdenum-based liquid phased in an in-flow micro-scale regime.
Nonwoven Releasing Propolis as a Potential New Wound Healing Method—A Review
Authors: Stojko Mateusz , Wolny Daniel , Włodarczyk Jakub
Published: September 2021

Wound healing poses a serious therapeutic problem. Methods which accelerate tissue regeneration and minimize or eliminate complications are constantly being sought. This paper is aimed at evaluation of the potential use of biodegradable polymer nonwovens releasing propolis as wound healing dressings, based on the literature data. Propolis is honeybee product with antioxidant, antibacterial, antifungal, anticancer, anti-inflammatory, analgesic, and regenerative properties. Controlled release of this substance throughout the healing should promote healing process, reduce the risk of wound infection, and improve aesthetic effect. The use of biodegradable aliphatic polyesters and polyester carbonates as a propolis carrier eliminates the problem of local drug administration and dressing changes. Well-known degradation processes and kinetics of the active substance release allows the selection of the material composition appropriate to the therapy. The electrospinning method allows the production of nonwovens that protect the wound against mechanical damage. Moreover, this processing technique enables adjusting product properties by modifying the production parameters. It can be concluded that biodegradable polymer dressings, releasing a propolis, may find potential application in the treatment of complicated wounds, as they may increase the effectiveness of treatment, as well as improve the patient’s life quality.
Copper(II)-Mediated Iodination of 1-Nitroso-2-naphthol
Authors: Efimenko Zarina M. , Rozhkov Anton V. , Suslonov Vitalii V. , Kuznetsov Maxim L. , Kukushkin Vadim Yu. , Bokach Nadezhda A.
Published: September 2021

The 3-Iodo-1-nitrosonaphthalene-2-ol (I-NON) was obtained by the copper(II)-mediated iodination of 1-nitroso-2-naphthol (NON). The suitable reactants and optimized reaction conditions, providing 94% NMR yield of I-NON, included the usage of Cu(OAc)2·H2O and 1:2:8 CuII/NON/I2 molar ratio between the reactants. The obtained I-NON was characterized by elemental analyses (C, H, N), high-resolution ESI+-MS, 1H and 13C{1H} NMR, FTIR, UV-vis spectroscopy, TGA, and X-ray crystallography (XRD). The copper(II) complexes bearing deprotonated I-NON were prepared as follows: cis-[Cu(I-NON–H)(I-NON)](I3) (1) was obtained by the reaction between Cu(NON-H)2 and I2 in CHCl3/MeOH, while trans-[Cu(I-NON–H)2] (2) was synthesized from I-NON and Cu(OAc)2 in MeOH. Crystals of trans-[Cu(I-NON–H)2(THF)2] (3) and trans-[Cu(I-NON–H)2(Py)2] (4) were precipitated from solutions of 2 in CHCl3/THF and Py/CHCl3/MeOH mixtures, respectively. The structures of 1 and 3–4 were additionally verified by X-ray crystallography. The characteristic feature of the structures of 1 and 3 is the presence of intermolecular halogen bonds with the involvement of the iodine center of the metal-bound deprotonated I-NON. The nature of the I···I and I···O contacts in the structures of 1 and 3, correspondingly, were studied theoretically at the DFT (PBE0-D3BJ) level using the QTAIM, ESP, ELF, NBO, and IGM methods.
Ameliorating Effect on Aβ-Induced Alzheimer’s Mice by Litsea cubeba Persoon Powder
Authors: Lee Kuan-Tseng , Chu Chen-Yeon , Chiang Shen-Shih
Published: September 2021

Alzheimer’s disease (AD) is caused by excessive oxidative damage and aging. The objective of this study was to investigate the anti-dementia effect of LCP fruit powder on amyloid β (Aβ)-induced Alzheimer’s mice. The composition of LCP essential oil was determined by gas chromatography/mass spectrometry. In addition, the water maze was used to evaluate the learning and memorizing abilities of the mice. The concentrations of malondialdehyde (MDA), protein carbonyl, phosphorylated τ-protein, and the deposition of Aβ plaques in mouse brains were also assessed. The results showed that the main components of essential oils in LCP and d-limonene, neral, and geranial contents were 14.15%, 30.94%, and 31.74%, respectively. Furthermore, oral administration with different dosages of LCP significantly decreased the escape time (21.25~33.62 s) and distance (3.23~5.07 m) in the reference memory test, and increased the duration time (26.14~28.90 s) and crossing frequency (7.00~7.88 times) in the target zone of probe test (p < 0.05). LCP also inhibited the contents of MDA and the phosphor-τ-protein from oxidative stress, reduced the brain atrophy by about 3~8%, and decreased the percentage of Aβ plaques from 0.44 to 0.05%. Finally, it was observed that the minimum dosage of LCP fruit powder (LLCP, 30.2 mg/day) could prevent oxidative stress induced by Aβ and subsequently facilitate memory and learning deficits in Aβ-induced neurotoxicity and cognitively impaired mice.
Effects of Temperature on Enantiomerization Energy and Distribution of Isomers in the Chiral Cu13 Cluster
Authors: Castillo-Quevedo Cesar , Buelna-Garcia Carlos Emiliano , Paredes-Sotelo Edgar , Robles-Chaparro Eduardo , Zamora-Gonzalez Edgar , Martin-del-Campo-Solis Martha Fabiola , Quiroz-Castillo Jesus Manuel , del-Castillo-Castro Teresa , Martínez-Guajardo Gerardo , de-Leon-Flores Aned , Cortez-Valadez Manuel , Ortiz-Chi Filiberto , Gaxiola Tulio , Castillo Santos Jesus , Vásquez-Espinal Alejandro , Pan Sudip , Cabellos Jose Luis
Published: September 2021

In this study, we report the lowest energy structure of bare Cu13 nanoclusters as a pair of enantiomers at room temperature. Moreover, we compute the enantiomerization energy for the interconversion from minus to plus structures in the chiral putative global minimum for temperatures ranging from 20 to 1300 K. Additionally, employing nanothermodynamics, we compute the probabilities of occurrence for each particular isomer as a function of temperature. To achieve that, we explore the free energy surface of the Cu13 cluster, employing a genetic algorithm coupled with density functional theory. Moreover, we discuss the energetic ordering of isomers computed with various density functionals. Based on the computed thermal population, our results show that the chiral putative global minimum strongly dominates at room temperature.
Molecular and Supramolecular Structures of Triiodides and Polyiodobismuthates of Phenylenediammonium and Its N,N-dimethyl Derivative
Authors: Shestimerova Tatiana A. , Golubev Nikita A. , Bykov Mikhail A. , Mironov Andrei V. , Fateev Sergey A. , Tarasov Alexey B. , Turkevych Ivan , Wei Zheng , Dikarev Evgeny V. , Shevelkov Andrei V.
Published: September 2021

Despite remarkable progress in photoconversion efficiency, the toxicity of lead-based hybrid perovskites remains an important issue hindering their applications in consumer optoelectronic devices, such as solar cells, LED displays, and photodetectors. For that reason, lead-free metal halide complexes have attracted great attention as alternative optoelectronic materials. In this work, we demonstrate that reactions of two aromatic diamines with iodine in hydroiodic acid produced phenylenediammonium (PDA) and N,N-dimethyl-phenylenediammonium (DMPDA) triiodides, PDA(I3)2⋅2H2O and DMPDA(I3)I, respectively. If the source of bismuth was added, they were converted into previously reported PDA(BiI4)2⋅I2 and new (DMPDA)2(BiI6)(I3)⋅2H2O, having band gaps of 1.45 and 1.7 eV, respectively, which are in the optimal range for efficient solar light absorbers. All four compounds presented organic–inorganic hybrids, whose supramolecular structures were based on a variety of intermolecular forces, including (N)H⋅⋅⋅I and (N)H⋅⋅⋅O hydrogen bonds as well as I⋅⋅⋅I secondary and weak interactions. Details of their molecular and supramolecular structures are discussed based on single-crystal X-ray diffraction data, thermal analysis, and Raman and optical spectroscopy.
The Surge of Metal–Organic-Framework (MOFs)-Based Electrodes as Key Elements in Electrochemically Driven Processes for the Environment
Authors: Thiam Abdoulaye , Lopez-Ruiz Juan A. , Barpaga Dushyant , Garcia-Segura Sergi
Published: September 2021

Metal–organic-frameworks (MOFs) are emerging materials used in the environmental electrochemistry community for Faradaic and non-Faradaic water remediation technologies. It has been concluded that MOF-based materials show improvement in performance compared to traditional (non-)faradaic materials. In particular, this review outlines MOF synthesis and their application in the fields of electron- and photoelectron-Fenton degradation reactions, photoelectrocatalytic degradations, and capacitive deionization physical separations. This work overviews the main electrode materials used for the different environmental remediation processes, discusses the main performance enhancements achieved via the utilization of MOFs compared to traditional materials, and provides perspective and insights for the further development of the utilization of MOF-derived materials in electrified water treatment.
First and Second Dissociation Enthalpies in Bi-Component Crystals Consisting of Maleic Acid and L-Phenylalanine
Authors: Feliciano Inês O. , Silva Daniela P. , Piedade M. Fátima M. , Bernardes Carlos E. S. , Minas da Piedade Manuel E.
Published: September 2021

The energetics of the stepwise dissociation of a A:B2 bi-component crystal, according to A:B2(cr) → A:B(cr) + B(cr) and A:B(cr) → A(cr) + B(cr), was investigated using MA:Phe2 and MA:Phe (MA = maleic acid; Phe = L-phenylalanine) as model systems. The enthalpy changes associated with these sequential processes and with the overall dissociation reaction A:B2(cr) → A(cr) + 2B(cr) were determined by solution calorimetry. It was found that they are all positive, indicating that there is a lattice enthalpy gain when MA:Phe2 is formed, either from the individual precursors or by adding Phe to MA:Phe. Single-crystal X-ray diffraction (SCXRD) analysis showed that MA:Phe2 is best described as a protic salt containing a maleate anion (MA−) and two non-equivalent L-phenylalanine units, both linked to MA− by NH···O hydrogen bonds (H-bond): one of these units is protonated (HPhe+) and the other zwitterionic (Phe±). Only MA− and HPhe+ molecules are present in the MA:Phe lattice. In this case, however, NH···O and OH···O H-bonds are formed between each MA− unit and two HPhe+ molecules. Despite these structural differences, the enthalpy cost for the removal of the zwitterionic Phe± unit from the MA:Phe2 lattice to yield MA:Phe is only 0.9 ± 0.4 kJ mol−1 higher than that for the dissociation of MA:Phe, which requires a proton transfer from HPhe+ to MA− and the rearrangement of L-phenylalanine to the zwitterionic, Phe±, form. Finally, a comparison of the dissociation energetics and structures of MA:Phe and of the previously reported glycine maleate (MA:Gly) analogue indicated that parameters, such as the packing coefficient, density, hydrogen bonds formed, or fusion temperature, are not necessarily good descriptors of dissociation enthalpy or lattice enthalpy trends when bi-component crystals with different molecular composition are being compared, even if the stoichiometry is the same.
Hydrogen Bonding Directed Self-Assembly of a Binuclear Ag(I) Metallacycle into a 1D Supramolecular Polymer
Authors: Brzechwa-Chodzyńska Anna , Gołdyn Mateusz , Walczak Anna , Harrowfield Jack M. , Stefankiewicz Artur R.
Published: September 2021

An Ag(I) metallacycle obtained unexpectedly during the preparation of Pd(II) complexes of the bifunctional ligand 5-([2,2′-bipyridin]-5-yl)pyrimidine-2-amine (L) has been characterized using X-ray structure determination as a binuclear, metallacyclic species [Ag2L2](SbF6)2, where both the bipyridine and pyrimidine-N donors of L are involved in coordination to the metal. The full coordination environment of the Ag(I) defines a case of highly irregular 4-coordination. In the crystal, the Ag-metallacycles assemble into one-dimensional supramolecular metalladynamers linked together by hydrogen-bonding interactions.
Lead Assays with Smartphone Detection Using a Monolithic Rod with 4-(2-Pyridylazo) Resorcinol
Authors: Issarangkura Na Ayutthaya Piyanat , Yeerum Chonnipa , Kesonkan Kullapon , Kiwfo Kanokwan , Grudpan Kate , Teshima Norio , Murakami Hiroya , Vongboot Monnapat
Published: September 2021

A monolithic rod of polyurethane foam–[4-(2-pyridylazo) resorcinol] (PUF–PAR) as a simple chemical sensor for lead assays with smartphone detection and image processing was developed. With readily available simple apparatus such as a plastic cup and a stirrer rod, the monolithic PUF rod was synthesized in a glass tube. The monolithic PUF–PAR rod could be directly loaded by standard/sample solution without sample preparation. A one-shot image in G/B value from a profile plot in ImageJ for a sample with triplicate results via a single standard calibration approach was obtained. A linear single standard calibration was: [G/B value] = −0.038[µg Pb2+] + 2.827, R2 = 0.95 for 10–30 µg Pb2+ with a limit of quantitation (LOQ) of 33 µg L−1. The precision was lower than 15% RSD. The proposed method was tested by an assay for Pb2+ contents in drinking water samples from Bangkok. The results obtained by the proposed method agree with those of ICP-OES and with 100–120% recovery, demonstrating that the method is useful for screening on-site water monitoring.
In Silico Evaluation of Iranian Medicinal Plant Phytoconstituents as Inhibitors against Main Protease and the Receptor-Binding Domain of SARS-CoV-2
Authors: Mousavi Seyyed Sasan , Karami Akbar , Haghighi Tahereh Movahhed , Tumilaar Sefren Geiner , Fatimawali  , Idroes Rinaldi , Mahmud Shafi , Celik Ismail , Ağagündüz Duygu , Tallei Trina Ekawati , Emran Talha Bin , Capasso Raffaele
Published: September 2021

The novel coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initially appeared in Wuhan, China, in December 2019. Elderly individuals and those with comorbid conditions may be more vulnerable to this disease. Consequently, several research laboratories continue to focus on developing drugs to treat this infection because this disease has developed into a global pandemic with an extremely limited number of specific treatments available. Natural herbal remedies have long been used to treat illnesses in a variety of cultures. Modern medicine has achieved success due to the effectiveness of traditional medicines, which are derived from medicinal plants. The objective of this study was to determine whether components of natural origin from Iranian medicinal plants have an antiviral effect that can prevent humans from this coronavirus infection using the most reliable molecular docking method; in our case, we focused on the main protease (Mpro) and a receptor-binding domain (RBD). The results of molecular docking showed that among 169 molecules of natural origin from common Iranian medicinal plants, 20 molecules (chelidimerine, rutin, fumariline, catechin gallate, adlumidine, astragalin, somniferine, etc.) can be proposed as inhibitors against this coronavirus based on the binding free energy and type of interactions between these molecules and the studied proteins. Moreover, a molecular dynamics simulation study revealed that the chelidimerine–Mpro and somniferine–RBD complexes were stable for up to 50 ns below 0.5 nm. Our results provide valuable insights into this mechanism, which sheds light on future structure-based designs of high-potency inhibitors for SARS-CoV-2.