bluuebunny/crossref_metadata_2025 huggingface dataset:
Phthalate Esters Metabolic Strain Gordonia sp. GZ-YC7, a Potential Soil Degrader for High Concentration Di-(2-ethylhexyl) Phthalate
Authors: Hu Tong , Yang Chen , Hou Zhengyu , Liu Tengfei , Mei Xiaotong , Zheng Lianbao , Zhong Weihong
Published: March 2022

As commonly used chemical plasticizers in plastic products, phthalate esters have become a serious ubiquitous environmental pollutant, such as in soil of plastic film mulch culture. Microbial degradation or transformation was regarded as a suitable strategy to solve the phthalate esters pollution. Thus, a new phthalate esters degrading strain Gordonia sp. GZ-YC7 was isolated in this study, which exhibited the highest di-(2-ethylhexyl) phthalate degradation efficiency under 1000 mg/L and the strongest tolerance to 4000 mg/L. The comparative genomic analysis results showed that there exist diverse esterases for various phthalate esters such as di-(2-ethylhexyl) phthalate and dibutyl phthalate in Gordonia sp. GZ-YC7. This genome characteristic possibly contributes to its broad substrate spectrum, high degrading efficiency, and high tolerance to phthalate esters. Gordonia sp. GZ-YC7 has potential for the bioremediation of phthalate esters in polluted soil environments.
Molecular Typing, Antibiotic Resistance and Enterotoxin Gene Profiles of Staphylococcus aureus Isolated from Humans in South Korea
Authors: Yoon Sunghyun , Park Yon Kyoung , Jung Tae Sung , Park Seong Bin
Published: March 2022

The emergence of antimicrobial-resistant Staphylococcus aureus has become a grave concern worldwide. In this study, 95 strains of S. aureus isolated from stool samples were collected from Busan, South Korea to characterize their antimicrobial susceptibility, enterotoxin genes, and molecular typing using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and random amplification of polymorphic DNA (RAPD) assay. Only two strains showed no drug resistance, whereas resistance to three or more antibiotics was observed in 87.4% of strains. Ampicillin resistance was the most common at 90% and all strains were susceptible to vancomycin. The distribution of enterotoxin genes encoded in isolates was sea (32.6%), sec (11.6%), seg (19%), sea & sec (2.1%), and sec & seg (34.7%). Molecular typing using both MALDI-TOF MS and RAPD indicated that S. aureus exhibited diverse clonal lineages and no correlations were observed among the profiling of enterotoxin, MALDI-TOF MS, and RAPD. This investigation provides useful information on foodborne pathogenic S. aureus that has a significant public health impact in South Korea.
Geo-Spatial Characteristics of 567 Places of Tick-Borne Encephalitis Infection in Southern Germany, 2018–2020
Authors: Friedsam Amelie M. , Brady Oliver J. , Pilic Antonia , Dobler Gerhard , Hellenbrand Wiebke , Nygren Teresa M.
Published: March 2022

Tick-borne encephalitis (TBE) is a growing public health problem with increasing incidence and expanding risk areas. Improved prevention requires better understanding of the spatial distribution and ecological determinants of TBE transmission. However, a TBE risk map at sub-district level is still missing for Germany. We investigated the distribution and geo-spatial characteristics of 567 self-reported places of probable TBE infection (POI) from 359 cases notified in 2018–2020 in the study area of Bavaria and Baden-Wuerttemberg, compared to 41 confirmed TBE foci and 1701 random comparator places. We built an ecological niche model to interpolate TBE risk to the entire study area. POI were distributed heterogeneously at sub-district level, as predicted probabilities varied markedly across regions (range 0–93%). POI were spatially associated with abiotic, biotic, and anthropogenic geo-spatial characteristics, including summer precipitation, population density, and annual frost days. The model performed with 69% sensitivity and 63% specificity at an optimised probability threshold (0.28) and an area under the curve of 0.73. We observed high predictive probabilities in small-scale areas, consistent with the known circulation of the TBE virus in spatially restricted microfoci. Supported by further field work, our findings may help identify new TBE foci. Our fine-grained risk map could supplement targeted prevention in risk areas.
Organelle Engineering in Yeast: Enhanced Production of Protopanaxadiol through Manipulation of Peroxisome Proliferation in Saccharomyces cerevisiae
Authors: Choi Bo , Kang Hyun , Kim Sun , Lee Pyung
Published: March 2022

Isoprenoids, which are natural compounds with diverse structures, possess several biological activities that are beneficial to humans. A major consideration in isoprenoid production in microbial hosts is that the accumulation of biosynthesized isoprenoid within intracellular membranes may impede balanced cell growth, which may consequently reduce the desired yield of the target isoprenoid. As a strategy to overcome this suggested limitation, we selected peroxisome membranes as depots for the additional storage of biosynthesized isoprenoids to facilitate increased isoprenoid production in Saccharomyces cerevisiae. To maximize the peroxisome membrane storage capacity of S.cerevisiae, the copy number and size of peroxisomes were increased through genetic engineering of the expression of three peroxisome biogenesis-related peroxins (Pex11p, Pex34p, and Atg36p). The genetically enlarged and high copied peroxisomes in S.cerevisiae were stably maintained under a bioreactor fermentation condition. The peroxisome-engineered S.cerevisiae strains were then utilized as host strains for metabolic engineering of heterologous protopanaxadiol pathway. The yields of protopanaxadiol from the engineered peroxisome strains were ca 78% higher than those of the parent strain, which strongly supports the rationale for harnessing the storage capacity of the peroxisome membrane to accommodate the biosynthesized compounds. Consequently, this study presents in-depth knowledge on peroxisome biogenesis engineering in S.cerevisiae and could serve as basic information for improvement in ginsenosides production and as a potential platform to be utilized for other isoprenoids.
Characterization of Monochromate and Hemichromate AFm Phases and Chromate-Containing Ettringite by 1H, 27Al, and 53Cr MAS NMR Spectroscopy
Authors: Nie Shuai , Skibsted Jørgen
Published: March 2022

The calcium aluminate hydrate AFm and AFt phases formed upon hydration of Portland cement have an important role in the stabilization and solidification of hazardous chromate ions in hardened cement. AFm monochromate (Ca4[Al(OH)6]2(CrO4)·12H2O), AFm hemichromate (Ca4[Al(OH)6]2(CrO4)0.5(OH)·12H2O) and the chromate-containing AFt phase, Ca6[Al(OH)6]2-(CrO4)3·24H2O, were synthesized and investigated by 1H, 27Al, and 53Cr MAS NMR spectroscopy. 27Al quadrupolar coupling parameters (CQ, ηQ) and isotropic chemical shifts (δiso) were determined for the three phases, including two distinct Al sites in chromate-AFt, as observed by 27Al MAS and MQMAS NMR. Two dominant peaks are apparent in the 1H MAS NMR spectra of each of the phases. For the AFm phases, these resonances are assigned to framework hydroxyl groups (1.7–2.0 ppm) and water molecules/hydroxyls (5.0–5.5 ppm) in the interlayer. For chromate-AFt, the peaks are ascribed to framework hydroxyl groups in the [Ca6Al2(OH)12]6+ columns (~1.4 ppm) and water molecules (~4.8 ppm) associated with the Ca ions. 53Cr MAS NMR spectra acquired at 22.3 T for the samples show a narrow resonance for both chromate AFm phases, whereas indications of three distinct Cr resonances are apparent for the chromate AFt. The absence of any second-order quadrupolar effects in the 53Cr NMR spectra strongly suggests that the chromate ions are highly mobile in the anionic sites of the AFm and AFt structures. The NMR data reported in this work are in agreement with the reported crystal structures for the chromate AFm and AFt phases and may be useful for identification and characterization of chromate fixation in cementitious systems, complementing information gained from conventional powder X-ray diffraction studies.
The Early Paleozoic Tectonic Framework and Evolution of Northern West Qinling Orogen: By Zircon U-Pb Dating and Geochemistry of Rocks from Tianshui and Sunjiaxia
Authors: Liu Zhen , Xu Wei , Liu Chunming , Xin Yujia , Huang Dezhi
Published: March 2022

The Tianshui-Sunjiaxia area is located in the connection zone of West Qinling Orogen and North Qilian Orogen, which could provide great insights into the amalgamation processes between the northern and southern blocks of China. Three subduction- and rift-related rocks gneissic granite from North Qilian arc-interarc belt (NQAI) granite and metabasalt from North Qinling back-arc basin (NQBA) are distinguished across the connection zone. The gneissic granite was generated by melts from older crustal materials of Longshan Group with the addition of a relatively juvenile basaltic source from the lower crust during the collision process. The Liwanxincun metabasalt reflects the mixing of the partial melting of the shallow asthenospheric mantle and the metasomatized mantle in a back-arc extension setting. The LA-ICP-MS zircon U-Pb dating of gneissic granite (068, 069) yields crystallization ages of 457.0 ± 1.6 Ma and 445.9 ± 2.1 Ma. The study area is divided into six tectonic units in Early Paleozoic time involving NQAI (Yanjiadian-Xinjie) continental arc, interarc rift basin (Maojiamo-Xiwali), continental arc (Chenjiahe-Wangjiacha); NQBA back-arc rift basin (Huluhe-Hongtubao), island arc and ophiolitic melange belt (North Qinling-Shangdan). A tectonic model is proposed in which the NQAI continental arc (Yanjiadian-Xinjie) might represent the early period of subduction of North Qilian Ocean (NQO) and the interarc rift is the product of the extension triggered by southward subduction of NQO. The ongoing subduction of NQO then leads to the formation of Chenjiahe-Wangjiacha continental arc, as well as the Hongtubao back-arc spreading ridge in NQBA back-arc basin (Huluhe). The tectonic evolution of the connection zone is closely associated with the closure of the North Qilian Ocean and North Qinling-Shangdan Ocean in the context of the convergence process of micro-continental blocks, including North China block, Longshan group and North Qinling Terrane.
A Comprehensive Recovery Process for Selective Separation and Enrichment of Copper, Zinc and Iron Minerals from a Polymetallic Ore and the Adsorption Mechanism of Collector Z-200
Authors: Xu Bin , Zhong Shouguo , Wu Jintian , Zhou Yujuan , Yang Yongbin , Li Qian , Jiang Tao
Published: March 2022

A comprehensive recovery process for the selective separation and enrichment of copper, zinc and iron minerals from a polymetallic ore was developed, which consisted of copper flotation, zinc flotation, and iron magnetic separation, and the adsorption mechanism of the copper collector Z-200 (O-isopropyl-N-ethyl thionocarbamate) was also studied in this work. The contents of the main valuable metallic elements of Cu, Zn and Fe in the ore were respectively 0.61%, 1.68% and 14.17%, and they mainly existed as chalcopyrite, sphalerite and magnetite, whose dissemination relationship was complex. Under the optimal conditions of this process, the recoveries of Cu, Zn and Fe in their respective concentrates reached 86.1%, 87.6% and 77.8%, and their grades were separately 20.31%, 45.97% and 63.39%. This process realized the selective separation and beneficiation of copper, zinc, and iron minerals from the ore, and had promising industrial application prospects. The adsorption configuration analysis demonstrated that the steadiest adsorption configurations of Z-200 on the surfaces of chalcopyrite, sphalerite and magnetite were the simultaneous adsorption of carbonyl S together with the O atom. Compared with sphalerite and magnetite, Z-200 was more prone to adsorb on the chalcopyrite surface. The Mulliken charge population and bond length analyses manifested that Z-200 chemically adsorbed on the chalcopyrite surface by forming a normal covalent bond and a back donation covalent bond, and the normal covalent bond played a leading role. The chemisorption of Z-00 was supported by the FTIR spectrum analysis result.
Comparative Analysis of Microbial Consortiums and Nanoparticles for Rehabilitating Petroleum Waste Contaminated Soils
Authors: Sattar Shehla , Siddiqui Samina , Shahzad Asim , Bano Asghari , Naeem Muhammad , Hussain Rahib , Khan Naeem , Jan Basit Latief , Yasmin Humaira
Published: March 2022

Nano-bioremediation application is an ecologically and environmentally friendly technique to overcome the catastrophic situation in soil because of petroleum waste contamination. We evaluated the efficiency of oil-degrading bacterial consortium and silver nanoparticles (AgNPs) with or without fertilizer to remediate soils collected from petroleum waste contaminated oil fields. Physicochemical characteristics of control soil and petroleum contaminated soils were assessed. Four oil-degrading strains, namely Bacillus pumilus (KY010576), Exiguobacteriaum aurantiacum (KY010578), Lysinibacillus fusiformis (KY010586), and Pseudomonas putida (KX580766), were selected based on their in vitrohydrocarbon-degrading efficiency. In a lab experiment, contaminated soils were treated alone and with combined amendments of the bacterial consortium, AgNPs, and fertilizers (ammonium nitrate and diammonium phosphate). We detected the degradation rate of total petroleum hydrocarbons (TPHs) of the soil samples with GC-FID at different intervals of the incubation period (0, 5, 20, 60, 240 days). The bacterial population (CFU/g) was also monitored during the entire period of incubation. The results showed that 70% more TPH was degraded with a consortium with their sole application in 20 days of incubation. There was a positive correlation between TPH degradation and the 100-fold increase in bacterial population in contaminated soils. This study revealed that bacterial consortiums alone showed the maximum increase in the degradation of TPHs at 20 days. The application of nanoparticles and fertilizer has non-significant effects on the consortium degradation potential. Moreover, fertilizer alone or in combination with AgNPs and consortium slows the rate of degradation of TPHs over a short period. Still, it subsequently accelerates the rate of degradation of TPHs, and a negligible amount remains at the end of the incubation period.
Enhanced Anti-Skin-Aging Activity of Yeast Extract-Treated Resveratrol Rice DJ526
Authors: Kantayos Vipada , Kim Jin-Suk , Baek So-Hyeon
Published: March 2022

Resveratrol is a powerful antioxidant that defends against oxidative stress in cells but is not found in large quantities in plants. Resveratrol-enriched rice DJ526, which was developed as a functional crop, shows a diverse range of biological activities. Resveratrol production is measured as total resveratrol and its glycoside, piceid, which is mainly found in plant-derived resveratrol. In the present study, elicitation using yeast extract (YE), methyl jasmonate, and jasmonic acid increased resveratrol production in DJ526 rice seeds. DJ526 seeds elicited using 1 g/L (YE1) and 5 g/L yeast extract (YE5) showed enhanced resveratrol production and antioxidant activity. YE5-treated DJ526 seeds showed decreased melanin content by 46.1% and 37.0% compared with the negative control and DJ526 (non-elicitation), respectively. Both YE1 and YE5 efficiently improved the wound-healing activity by reducing the wound gap faster than in untreated cells, with a maximum rate of 60.2% at 24 h and complete closure at 48 h. YE1 and YE5 significantly decreased the levels of proinflammatory cytokine, TNF-α, and enhanced collagen synthesis in inflammatory cells. These findings indicate that YE-treated resveratrol rice DJ526 may improve resveratrol production and could be an active antiaging ingredient for cosmetic and skin therapy applications.
Silver Nanowires and Silanes in Hybrid Functionalization of Aramid Fabrics
Authors: Nejman Alicja , Baranowska-Korczyc Anna , Ranoszek-Soliwoda Katarzyna , Jasińska Izabela , Celichowski Grzegorz , Cieślak Małgorzata
Published: March 2022

New functionalization methods of meta- and para-aramid fabrics with silver nanowires (AgNWs) and two silanes (3-aminopropyltriethoxysilane (APTES)) and diethoxydimethylsilane (DEDMS) were developed: a one-step method (mixture) with AgNWs dispersed in the silane mixture and a two-step method (layer-by-layer) in which the silanes mixture was applied to the previously deposited AgNWs layer. The fabrics were pre-treated in a low-pressure air radio frequency (RF) plasma and subsequently coated with polydopamine. The modified fabrics acquired hydrophobic properties (contact angle ΘW of 112–125°). The surface free energy for both modified fabrics was approximately 29 mJ/m2, while for reference, meta- and para-aramid fabrics have a free energy of 53 mJ/m2 and 40 mJ/m2, respectively. The electrical surface resistance (Rs) was on the order of 102 Ω and 104 Ω for the two-step and one-step method, respectively. The electrical volume resistance (Rv) for both modified fabrics was on the order of 102 Ω. After UV irradiation, the Rs did not change for the two-step method, and for the one-step method, it increased to the order of 1010 Ω. The specific strength values were higher by 71% and 63% for the meta-aramid fabric and by 102% and 110% for the para-aramid fabric for the two-step and one-step method, respectively, compared to the unmodified fabrics after UV radiation.
Modelling Protein Plasticity: The Example of Frataxin and Its Variants
Authors: Botticelli Simone , La Penna Giovanni , Nobili Germano , Rossi Giancarlo , Stellato Francesco , Morante Silvia
Published: March 2022

Frataxin (FXN) is a protein involved in storage and delivery of iron in the mitochondria. Single-point mutations in the FXN gene lead to reduced production of functional frataxin, with the consequent dyshomeostasis of iron. FXN variants are at the basis of neurological impairment (the Friedreich’s ataxia) and several types of cancer. By using altruistic metadynamics in conjunction with the maximal constrained entropy principle, we estimate the change of free energy in the protein unfolding of frataxin and of some of its pathological mutants. The sampled configurations highlight differences between the wild-type and mutated sequences in the stability of the folded state. In partial agreement with thermodynamic experiments, where most of the analyzed variants are characterized by lower thermal stability compared to wild type, the D104G variant is found with a stability comparable to the wild-type sequence and a lower water-accessible surface area. These observations, obtained with the new approach we propose in our work, point to a functional switch, affected by single-point mutations, of frataxin from iron storage to iron release. The method is suitable to investigate wide structural changes in proteins in general, after a proper tuning of the chosen collective variable used to perform the transition.
Innovative Green Chemistry Approach to Synthesis of Sn2+-Metal Complex and Design of Polymer Composites with Small Optical Band Gaps
Authors: Aziz Shujahadeen B. , Nofal Muaffaq M. , Brza Mohamad A. , Sadiq Niyaz M. , Dannoun Elham M. A. , Ahmed Khayal K. , Al-Saeedi Sameerah I. , Hussen Sarkawt A. , Hussein Ahang M.
Published: March 2022

In this work, the green method was used to synthesize Sn2+-metal complex by polyphenols (PPHs) of black tea (BT). The formation of Sn2+-PPHs metal complex was confirmed through UV-Vis and FTIR methods. The FTIR method shows that BT contains NH and OH functional groups, conjugated double bonds, and PPHs which are important to create the Sn2+-metal complexes. The synthesized Sn2+-PPHs metal complex was used successfully to decrease the optical energy band gap of PVA polymer. XRD method showed that the amorphous phase increased with increasing the metal complexes. The FTIR and XRD analysis show the complex formation between Sn2+-PPHs metal complex and PVA polymer. The enhancement in the optical properties of PVA was evidenced via UV-visible spectroscopy method. When Sn2+-PPHs metal complex was loaded to PVA, the refractive index and dielectric constant were improved. In addition, the absorption edge was also decreased to lower photon. The optical energy band gap decreases from 6.4 to 1.8 eV for PVAloaded with 30% (v/v) Sn2+-PPHs metal complex. The variations of dielectric constant versus wavelength of photon are examined to measure localized charge density (N/m*) and high frequency dielectric constant. By increasing Sn2+-PPHs metal complex, the N/m* are improved from 3.65 × 1055 to 13.38 × 1055 m−3 Kg−1. The oscillator dispersion energy (Ed) and average oscillator energy (Eo) are measured. The electronic transition natures in composite films are determined based on the Tauc’s method, whereas close examinations of the dielectric loss parameter are also held to measure the energy band gap.
Hydroxypyridinone-Based Metal Chelators towards Ecotoxicity: Remediation and Biological Mechanisms
Authors: Santos M. Amélia , Irto Anna , Buglyó Péter , Chaves Sílvia
Published: March 2022

Hydroxypyridinones (HPs) are recognized as excellent chemical tools for engineering a diversity of metal chelating agents, with high affinity for hard metal ions, exhibiting a broad range of activities and applications, namely in medical, biological and environmental contexts. They are easily made and functionalizable towards the tuning of their pharmacokinetic properties or the improving of their metal complex thermodynamic stabilities. In this review, an analysis of the recently published works on hydroxypyridinone-based ligands, that have been mostly addressed for environmental applications, namely for remediation of hard metal ion ecotoxicity in living beings and other biological matrices is carried out. In particular, herein the most recent developments in the design of new chelating systems, from bidentate mono-HP to polydentate multi-HP derivatives, with a structural diversity of soluble or solid-supported backbones are outlined. Along with the ligand design, an analysis of the relationship between their structures and activities is presented and discussed, namely associated with the metal affinity and the thermodynamic stability of the corresponding metal complexes.
Insecticidal and Enzyme Inhibition Activities of Leaf/Bark Extracts, Fractions, Seed Oil and Isolated Compounds from Triadica sebifera (L.) Small against Aphis craccivora Koch
Authors: Dolma Shudh Kirti , Singh Prithvi Pal , Reddy Sajjalavarahalli G. Eswara
Published: March 2022

Aphid, Aphis craccivora Koch (Hemiptera: Aphididae), is a major sap-sucking insect pest of leguminous crops and also transmits plant viruses, leading to economic yield loss. Indiscriminate and repeated use of insecticides for control of aphid leads to the development of resistance, and is harmful to the environment, non-target organisms, etc. Plant-based extracts/seed oils (SO) are the best alternatives to insecticides. Insecticidal activities of Triadica sebifera have not been reported against A. craccivora and other insect pests to date. In the current study, the main objective was to study the insecticidal activities of leaf/bark extracts/fractions, seed oil, isolated compounds, and their combinations against A. craccivora. Results showed that, among the extracts, ethanolic bark extract 80% (LC50 = 5115.98 mg/L) was more effective against A. craccivora. Among fractions, the n-hexane fraction of leaves (LC50 = 425.73 mg/L) and the ethyl acetate fraction of bark (LC50 = 813.45 mg/L) were promising. Among compounds, gallic acid was the most effective (LC50 = 1303.68 mg/L) compared to shikimic acid and quercetin. SO (LC50 = 850.94 mg/L) was superior compared to extracts/fractions/compounds. All the combinations showed toxicity and synergistic activity. Leaf/bark extracts and SO significantly inhibited the AChE and GST activity in A. craccivora. Based on field bio-efficacy, the leaf extract/SO or their combinations can be recommended for the control of aphids.
New Generation of MOF-Monoliths Based on Metal Foams
Authors: Delgado-Marín José J. , Izan Dennis P. , Molina-Sabio Miguel , Ramos-Fernandez Enrique V. , Narciso Javier
Published: March 2022

Herein, it has been developed a method to prepare metallic foams starting from Zamak5 (ZnAlCu alloy) with different pore sizes. The Zamak5 metallic foam is designed to serve as a support and metallic precursor of ZIF-8. In this way, composite materials MOF-metal can be prepared, these composites have a large number of application in energy exchange processe such as: adsorption or chemical reactions. Additionally, this method of sythesizing MOFs is environmentally friendly thanks to absence of solvents. Hanerssing the low melting point of the linker, the linker is infiltrated into the foam where the foam and the linker react to form the ZIF-8. In this way we have managed to transform part of the foam into ZIF-8 crystals that remain adhered to the foam. The foams have been characterized and modeled studying the mechanical and electrical properties, finding that both can be predected by various models. Among these, Ashby and Mortensen models for mechanical properties and Ashby and Percolation model for electrical properties stand.
In Vitro Bioaccessibility of Bioactive Compounds from Rosehip-Enriched Corn Extrudates
Authors: Igual Marta , Păucean Adriana , Vodnar Dan Cristian , García-Segovia Purificación , Martínez-Monzó Javier , Chiş Maria Simona
Published: March 2022

The rosehip (Rosa canina L.) fruit has gained researchers′ attention due to its rich chemical composition in vitamin C, phenols, carotenoids, and high antioxidant activity; meanwhile, polymers such as pea protein are generally recognized as exhibiting a protection role against the extrusion process. Corn snacks extrudates obtained by replacing corn flour with 10% R. canina powder (R) and 10% R. canina with pea protein (RPP) were evaluated for the physicochemical, textural, optical, and nutritional characteristics. A sample manufactured without R. canina powder was used as a control. Hardness, crispiness, chewiness, and solubility index (WSI) of the final extrudates were improved by addition of R. canina and pea protein powder (PP); meanwhile, b* (yellow/blue coordinate), C (chroma), and h* (tone) optical parameters were significantly different from the control sample (p < 0.05). Extrusion highlighted a negative impact on total phenols, carotenoids, vitamin C, and antioxidant activity extrudates, while PP exhibited a good protection against the extrusion process. In vitro digestion increased the bioaccessibility of vitamin C, folate, antioxidant activity, total phenols, and total carotenoids mainly on RPP extrudates.
Characterization of the Phenolic Profile and Antioxidant Activity of Cathissa reverchonii (Lange) Speta
Authors: Llorent-Martínez Eulogio J. , Gordo-Moreno Ana I. , Fernández-de Córdova María Luisa , Salazar-Mendías Carlos , Tercero-Araque Amanda
Published: March 2022

Cathissa reverchonii (formerly Ornithogalum reverchonii) is a threatened species, constituting an endemism present in the south of Spain and northern Morocco. In Spain, it is only found in two disjoint populations in the region of Andalusia. The determination of its chemical composition and the influence that environmental factors have on it can contribute significantly to the development of appropriate protection and conservation plans. However, there are no previous reports about this species to date. Consequently, this research aimed to study the phenolic composition and antioxidant activity of C. reverchonii and to assess the influence of environmental factors on the phenolic profile and bioactivity. The vegetal material was collected in seven places inhabited by the two separate populations in Spain. The phenolic composition of methanolic extracts of the species was determined by HPLC-ESI-Q-TOF-MS, and the antioxidant activity was assessed by DPPH and ABTS assays. Fifteen compounds were characterized in the extracts of the aerial parts of C. reverchonii, revealing differences in the phytochemical profile between both populations analyzed, mainly in the saponin fraction. The main phenolics were flavone di-C-glucoside (lucenin-2), followed by a quercetin-di-C-glucoside. The composition of the extracts of C. reverchonii and their radical scavenging power were compared with those of other species of the genus Ornithogalum L., revealing significant differences between the latter and the genus Cathissa.
Dried Plasma Spot Based LC–MS/MS Method for Monitoring of Meropenem in the Blood of Treated Patients
Authors: Cao Haiwei , Jiang Yi , Wang Shaomin , Cao Haihuan , Li Yanyan , Huang Jing
Published: March 2022

Meropenem (MER) is widely used to treat complicated and serious infections. Therapeutic drug monitoring (TDM) provides a valid clinical tool to avoid suboptimal concentrations and dose–related adverse reactions. However, TDM seems to face challenges since the limited stability of MER in plasma makes transport difficult between clinics and laboratories. Dried plasma spot (DPS) sampling is an attractive but underutilized method for TDM that has the desired features of easy collection, storage, and transport, and overcomes known hematocrit (HCT) issues in dried blood spot (DBS) analysis. This study was designed to investigate a DPS–based liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for quantification of MER. The method was developed and validated for DPS and wet plasma samples. Calibration curves were linear (R2 > 0.995) over the concentration range of 0.5–50 µg/mL. Overall accuracy and precision did not exceed 15% and no significant matrix effect was observed. MER has been more stable in DPS than in wet plasma samples. A comparison of DPS and wet plasma concentrations was assessed in 32 patients treated with MER. The results showed that there was no significant difference between the two methods. So the DPS method developed in this study is appropriate and practical for the monitor of MER in the daily clinical laboratory practice.
Impact of Charge Transfer Complex on the Dielectric Relaxation Processes in Poly(methyl methacrylate) Polymer
Authors: Alrooqi Arwa , Al-Amshany Zahra M. , Al-Harbi Laila M. , Altalhi Tariq A. , Refat Moamen S. , Hassanien A. M. , Atta A. A.
Published: March 2022

The impact of the charge transfer complex on the dielectric relaxation processes in free poly(methyl methacrylate) (PMMA) polymer sheets was investigated. The frequency dependence of dielectric properties was obtained over the frequency range 0.1 Hz–1 MHz at temperatures ranging between 303 K and 373 K for perylene dye and acceptors (picric acid (PA) and chloranilic acid (CLA)) in an in situ PMMA polymer. The TG/dTG technique was used to investigate the thermal degradation of the synthesized polymeric sheets. Additionally, the kinetic parameters have been assessed using the Coats–Redfern relation. The dielectric relaxation spectroscopy of the synthesized polymeric sheets was analyzed in terms of complex dielectric constant, dielectric loss, electrical modulus, electrical conductivity, and Cole–Cole impedance spectroscopy. α- and β-relaxation processes were detected and discussed. The σ(ω) dispersion curves of the synthesized polymeric sheets show two distinct regions with increasing frequency. The impedance data of the synthesized polymeric sheets can be represented by the equivalent circuit (parallel RC).
In Vitro Anti-Inflammatory Activity of Cotula anthemoides Essential Oil and In Silico Molecular Docking of Its Bioactives
Authors: Refaey Mohamed , Abouelela Mohamed , El-Shoura Ehab , Alkhalidi Hala , Fadil Sana , Elhady Sameh , Abdelhameed Reda
Published: March 2022

The genus Cotula (Asteraceae) comprises about 80 species, amongst them Cotula anthemoides L. It is a wild plant growing in Egypt that possesses many traditional uses as a headache, colic, and chest cold remedy. In our study, the chemical composition of C. anthemoides essential oils was analyzed using GC-MS spectroscopy. Sixteen components of leave and stem oils and thirteen components of flower oils were characterized. The main components in both essential oil parts were camphor (88.79% and 86.45%) and trans-thujone (5.14% and 10.40%) in the leaves and stems and the flowers, respectively. The anti-inflammatory activity of the oils in lipopolysaccharide-stimulated RAW 264.7 macrophage cells was evaluated. The flower oil showed its predominant effect in the amelioration of proinflammatory cytokines and tumor necrosis factor-α, as well as cyclooxygenase-2. The bornyl acetate showed the highest affinity for the cyclooxygenase-2 receptor, while compound cis-p-menth-2-ene-1-ol had the best affinity for the tumor necrosis factor receptor, according to the results of molecular docking. In addition, the molecule cis-β-farnesene showed promising dual affinity for both studied receptors. Our findings show that essential oils from C. anthemoides have anti-inflammatory properties through their control over the generation of inflammatory mediators. These findings suggest that C. anthemoides essential oils could lead to the discovery of novel sources of anti-inflammatory treatments.
Discovery of a New Drug-like Series of OGT Inhibitors by Virtual Screening
Authors: Loi Elena M. , Tomašič Tihomir , Balsollier Cyril , van Eekelen Kevin , Weiss Matjaž , Gobec Martina , Alteen Matthew G. , Vocadlo David J. , Pieters Roland J. , Anderluh Marko
Published: March 2022

O-GlcNAcylation is an essential post-translational modification installed by the enzyme O-β-N-acetyl-d-glucosaminyl transferase (OGT). Modulating this enzyme would be extremely valuable to better understand its role in the development of serious human pathologies, such as diabetes and cancer. However, the limited availability of potent and selective inhibitors hinders the validation of this potential therapeutic target. To explore new chemotypes that target the active site of OGT, we performed virtual screening of a large library of commercially available compounds with drug-like properties. We purchased samples of the most promising virtual hits and used enzyme assays to identify authentic leads. Structure-activity relationships of the best identified OGT inhibitor were explored by generating a small library of derivatives. Our best hit displays a novel uridine mimetic scaffold and inhibited the recombinant enzyme with an IC50 value of 7 µM. The current hit represents an excellent starting point for designing and developing a new set of OGT inhibitors that may prove useful for exploring the biology of OGT.
Drug Solubility Correlation Using the Jouyban–Acree Model: Effects of Concentration Units and Error Criteria
Authors: Rahimpour Elaheh , Alvani-Alamdari Sima , Acree William E. , Jouyban Abolghasem
Published: March 2022

An important factor affecting the model accuracy is the unit expression type for solute and solvent concentrations. One can report the solute and solvent concentration in various units and compare them with various error scales. In order to investigate the unit and error scale expression effects on the accuracy of the Jouyban–Acree model, in the current study, seventy-nine solubility data sets were collected randomly from the published articles and solute and solvent concentrations in the investigated systems were expressed in various units. Mass fraction, mole fraction, and volume fraction were the employed concentration units for the solvent compositions, and mole fraction, molar, and gram/liter were the investigated concentration units for the solutes. The solubility data, with various solute/solvent concentration units, were correlated using the Jouyban–Acree model, and the accuracy of each model for correlating the data was investigated by calculating different error scales and discussed.
Antiviral Properties of Silver Nanoparticles against SARS-CoV-2: Effects of Surface Coating and Particle Size
Authors: He Qinghao , Lu Jing , Liu Nian , Lu Wenqing , Li Yu , Shang Chao , Li Xiao , Hu Ligang , Jiang Guibin
Published: March 2022

Coronavirus disease 2019 (COVID-19) has spread rapidly and led to over 5 million deaths to date globally. Due to the successively emerging mutant strains, therapeutics and prevention against the causative virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are urgently needed. Prevention of SARS-CoV-2 infection in public and hospital areas is essential to reduce the frequency of infections. Silver nanoparticles (AgNPs) with virucidal effects have been reported. Therefore, we investigated the virucidal activity and safety of ten types of AgNPs with different surface modifications and particle sizes, in cells exposed to SARS-CoV-2 in vitro. The AgNPs could effectively inhibit the activity of SARS-CoV-2, and different surface modifications and particle sizes conferred different virucidal effects, of which 50-nm BPEI showed the strongest antiviral effect. We concluded that the efficacy of each type of AgNP type was positively correlated with the corresponding potential difference (R2 = 0.82). These in vitro experimental data provide scientific support for the development of therapeutics against COVID-19, as well as a research basis for the development of broad-spectrum virucides. Given the increasing acquired resistance of pathogens against conventional chemical and antibody-based drugs, AgNPs may well be a possible solution for cutting off the route of transmission, either as an external material or a potential medicine.
Large-Scale MOCVD Deposition of Nanostructured TiO2 on Stainless Steel Woven: A Systematic Investigation of Photoactivity as a Function of Film Thickness
Authors: Galenda Alessandro , Natile Marta Maria , El Habra Naida
Published: March 2022

Heterogeneous photocatalysis is considered as one of the most appealing options for the treatment of organic pollutants in water. However, its definitive translation into industrial practice is still very limited because of both the complexity of large-scale production of catalysts and the problems involved in handling the powder-based photocatalysts in the industrial plants. Here, we demonstrate that the MOCVD approach can be successfully used to prepare large-scale supported catalysts with a good photocatalytic activity towards dye degradation. The photocatalyst consisted of nanostructured TiO2 thin film deposited on a stainless steel mesh substrate. The film thickness, the morphological features, and the crystallographic properties of the different portions of the sample were correlated to the position in the reactor chamber and the reaction conditions. The photocatalytic activity was evaluated according to the international standard test ISO 10678:2010 based on methylene blue degradation. The photocatalytic activity is essentially constant (PMB over 40 µmol·m−2·h−1) throughout the film, except for the portion of sample placed at the very end of the reactor chamber, where the TiO2 film is too thin to react properly. It was assessed that a minimum film thickness of 250–300 nm is necessary to reach the maximum photocatalytic performance.
Aspects of Uniform Horizontal Magnetic Field and Nanoparticle Aggregation in the Flow of Nanofluid with Melting Heat Transfer
Authors: Wang Fuzhang , Kumar Rangaswamy Naveen , Prasannakumara Ballajja C. , Khan Umair , Zaib Aurang , Abdel-Aty Abdel-Haleem , Yahia Ibrahim S. , Alqahtani Mohammed S. , Galal Ahmed M.
Published: March 2022

The current exploration focuses on the impact of homogeneous and heterogeneous chemical reactions on titanium dioxide-ethylene glycol (EG)-based nanoliquid flow over a rotating disk with thermal radiation. In this paper, a horizontal uniform magnetic field is used to regularise the flow field produced by a rotating disk. Further, we conduct a comparative study on fluid flow with and without aggregation. Suitable transformations are used to convert the governing partial differential equations (PDEs) into ordinary differential equations (ODEs). Later, the attained system is solved numerically by means of the shooting method in conjunction with the Runge–Kutta–Fehlberg fourth-fifth-order method (RKF-45). The outcome reveals that the fluid flow without nanoparticle aggregation shows enhanced heat transport than for augmented values of melting parameter. Furthermore, for augmented values of strength of homogeneous and heterogeneous reaction parameters, the mass transfer is greater in fluid flow with aggregation conditions.
Area-Selective, In-Situ Growth of Pd-Modified ZnO Nanowires on MEMS Hydrogen Sensors
Authors: Hu Jiahao , Zhang Tao , Chen Ying , Xu Pengcheng , Zheng Dan , Li Xinxin
Published: March 2022

Nanomaterials are widely utilized as sensing materials in semiconductor gas sensors. As sensor sizes continue to shrink, it becomes increasingly challenging to construct micro-scale sensing materials on a micro-sensor with good uniformity and stability. Therefore, in-situ growth with a desired pattern in the tiny sensing area of a microsensor is highly demanded. In this work, we combine area-selective seed layer formation and hydrothermal growth for the in-situ growth of ZnO nanowires (NWs) on Micro-electromechanical Systems (MEMS)-based micro-hotplate gas sensors. The results show that the ZnO NWs are densely grown in the sensing area. With Pd nano-particles’ modification of the ZnO NWs, the sensor is used for hydrogen (H2) detection. The sensors with Pd-ZnO NWs show good repeatability as well as a reversible and uniform response to 2.5 ppm–200 ppm H2. Our approach offers a technical route for designing various kinds of gas sensors.
In Situ Growth of W2C/WS2 with Carbon-Nanotube Networks for Lithium-Ion Storage
Authors: Nguyen Thang Phan , Kim Il Tae
Published: March 2022

The combination of W2C and WS2 has emerged as a promising anode material for lithium-ion batteries. W2C possesses high conductivity but the W2C/WS2-alloy nanoflowers show unstable performance because of the lack of contact with the leaves of the nanoflower. In this study, carbon nanotubes (CNTs) were employed as conductive networks for in situ growth of W2C/WS2 alloys. The analysis of X-ray diffraction patterns and scanning/transmission electron microscopy showed that the presence of CNTs affected the growth of the alloys, encouraging the formation of a stacking layer with a lattice spacing of ~7.2 Å. Therefore, this self-adjustment in the structure facilitated the insertion/desertion of lithium ions into the active materials. The bare W2C/WS2-alloy anode showed inferior performance, with a capacity retention of ~300 mAh g−1 after 100 cycles. In contrast, the WCNT01 anode delivered a highly stable capacity of ~650 mAh g−1 after 100 cycles. The calculation based on impedance spectra suggested that the presence of CNTs improved the lithium-ion diffusion coefficient to 50 times that of bare nanoflowers. These results suggest the effectiveness of small quantities of CNTs on the in situ growth of sulfides/carbide alloys: CNTs create networks for the insertion/desertion of lithium ions and improve the cyclic performance of metal-sulfide-based lithium-ion batteries.
Non-Thermal Plasma Treatment Coupled with a Photocatalyst for Antimicrobial Performance of Ihram Cotton Fabric
Authors: Galaly Ahmed Rida , Dawood Nagia
Published: March 2022

All Muslim pilgrims must wear Ihram clothes during the Hajj and Umrah seasons, which presents a great challenge regarding how to eliminate the spread of microbes attached to the cotton fabric of Ihram from the surrounding environment. Targeted fashion research of the recent past presents a new industrial treatment, which has led us to study the impact of heat directed from an atmospheric pressure plasma jet (APPJ), coupled with photocatalytic nanomaterials, for the antibacterial treatment of Escherichia coli (E. coli) attached to cotton fabric samples, to improve pollutant remediation. The average rates of heat transfer to the bacterial colonies attached to cotton fabric samples, as a function of the laminar mode, were 230 and 77 mW for dry and wet argon discharges, respectively. The jet temperatures (TJ) and heat transfer (QH) decreased more for wet argon discharge than for dry argon discharge. This is because, due to the wettability by TiO2 photocatalyst concentration dosage increases from 0 to 0.5 g L−1, a proportion of the energy from the APPJ photons is expended in overcoming the bandgap of TiO2 and is used in the creation of electron–hole pairs. In the Weibull deactivation function used for the investigation of the antibacterial treatment of E. coli microbes attached to cotton fabric samples, the deactivation kinetic rate of E. coli increased from 0.0065 to 0.0152 min−1 as the TiO2 precursor concentration increased. This means that the sterilization rate increased despite (TJ) and (QH) decreasing as the wettability by TiO2 photocatalyst increases. This may be due to photocatalytic disinfection and the generation of active substances, in addition to the effect of the incident plume of the non-thermal jet.
Enhanced Fe-TiO2 Solar Photocatalysts on Porous Platforms for Water Purification
Authors: Matias Maria Leonor , Pimentel Ana , Reis-Machado Ana S. , Rodrigues Joana , Deuermeier Jonas , Fortunato Elvira , Martins Rodrigo , Nunes Daniela
Published: March 2022

In this study, polyethylene glycol-modified titanium dioxide (PEG-modified TiO2) nanopowders were prepared using a fast solvothermal method under microwave irradiation, and without any further calcination processes. These nanopowders were further impregnated on porous polymeric platforms by drop-casting. The effect of adding iron with different molar ratios (1, 2, and 5%) of iron precursor was investigated. The characterization of the produced materials was carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Optical characterization of all the materials was also carried out. SEM showed that pure TiO2 and Fe-TiO2 nanostructures presented similar nanosized and spherical particles, which uniformly covered the substrates. From XRD, pure TiO2 anatase was obtained for all nanopowders produced, which was further confirmed by Raman spectroscopy on the impregnated substrates. XPS and UV–VIS absorption spectroscopy emission spectra revealed that the presence of Fe ions on the Fe-TiO2 nanostructures led to the introduction of new intermediate energy levels, as well as defects that contributed to an enhancement in the photocatalytic performance. The photocatalytic results under solar radiation demonstrated increased photocatalytic activity in the presence of the 5% Fe-TiO2 nanostructures (Rhodamine B degradation of 85% after 3.5 h, compared to 74% with pure TiO2 for the same exposure time). The photodegradation rate of RhB dye with the Fe-TiO2 substrate was 1.5-times faster than pure TiO2. Reusability tests were also performed. The approach developed in this work originated novel functionalized photocatalytic platforms, which were revealed to be promising for the removal of organic dyes from wastewater.