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1.
BMC Complement Med Ther ; 22(1): 280, 2022 Oct 26.
Article in English | MEDLINE | ID: covidwho-2089189

ABSTRACT

BACKGROUND: Bersama abyssinica is a common herb in Africa, with diverse medical uses in different areas. The plant is well-known in Tanzania for treating respiratory disorders such as TB, tonsillitis, bronchitis, and asthma, and it has lately been utilized to treat COVID-19 symptoms. Water extract of leaf and stem bark has been registered as an herbal medication known as 'Coviba Dawa' in Tanzania for the relief of bacterial respiratory infections. The extracts, however, have not been scientifically tested for their anti-viral activities. The aim of this work was to test for the cytotoxicity and antiviral effects of bioactive ingredients from B. abyssinica extracts against the Delta variant of the SARS-CoV-2 coronavirus. METHODS: B. abyssinica leaves and stem bark were dried under shade in room temperature and then pulverized to obtain small pieces before soaking into different solvents. One hundred grams of each, leaves and stem bark, were extracted in petroleum ether, dichloromethane, ethyl acetate and methanol. Water extract was obtained by decoction of stem bark and leaves into water. Phenols, flavonoids, tannins, and antioxidants were confirmed as components of the extracts. Analysis of polar extracts of bark stem bark and leaves was done. Antiviral screening and cytotoxicity experiments were conducted in a Biosafety Level 3 (BSL-3) Laboratory facility according to International Standard Operating Procedures (SOPs). RESULTS: By the use of LC-MS/MS analysis, this study confirmed the existence of four phenolic compounds in B. abyssinica water extract; 2,4-di-tert-butylphenol, 4-formyl-2-methoxyphenyl propionate, 7,8-Dihydroxy-4-methylcoumarin, and 2,3, 6-trimethoxyflavone with antioxidant activity. This study showed that, while the water extracts of B. abyssinica had significant antiviral activity against SARS Cov2 virus, it showed no cytotoxicity effect on Vero E6 cells. In particular, the water extract (Coviba dawa) showed 75% while ethylacetate fraction of B. abyssinica leaves showed a 50% in vitro viral inhibition, indicating that these substances may be useful for the development of future anti-viral agents. CONCLUSION: We therefore recommend isolation of compounds for further profiling and development with a broader concentration range. We further recommend studies that determine the antiviral activity of extracts of B.abyssinica on other viral pathogens of clinical concern.


Subject(s)
COVID-19 , Magnoliopsida , Antioxidants/analysis , Plant Extracts/therapeutic use , Antiviral Agents/pharmacology , Water , SARS-CoV-2 , Methylene Chloride/analysis , Methanol , Chromatography, Liquid , Propionates , Tandem Mass Spectrometry , COVID-19/drug therapy , Phenols/pharmacology , Flavonoids/analysis , Tannins , Solvents/analysis , Tanzania
2.
Phys Chem Chem Phys ; 24(41): 25391-25402, 2022 Oct 27.
Article in English | MEDLINE | ID: covidwho-2077132

ABSTRACT

Here, we have carried out a proof-of-concept molecular dynamics (MD) simulation with adaptive tempering in a membrane mimetic environment to study the folding of single-pass membrane peptides. We tested the influenza A M2 viroporin, influenza B M2 viroporin, and protein E from coronaviruses MERS-Cov-2 and SARS-CoV-2 peptides with known experimental secondary structures in membrane bilayers. The two influenza-derived peptides are significantly different in the peptide sequence and secondary structure and more polar than the two coronavirus-derived peptides. Through a total of more than 50 µs of simulation time that could be accomplished in trifluoroethanol (TFE), as a membrane model, we characterized comparatively the folding behavior, helical stability, and helical propensity of these transmembrane peptides that match perfectly their experimental secondary structures, and we identified common motifs that reflect their quaternary organization and known (or not) biochemical function. We showed that BM2 is organized into two structurally distinct parts: a significantly more stable N-terminal half, and a fast-converting C-terminal half that continuously folds and unfolds between α-helical structures and non-canonical structures, which are mostly turns. In AM2, both the N-terminal half and C-terminal half are very flexible. In contrast, the two coronavirus-derived transmembrane peptides are much more stable and fast helix-formers when compared with the influenza ones. In particular, the SARS-derived peptide E appears to be the fastest and most stable helix-former of all the four viral peptides studied, with a helical structure that persists almost without disruption for the whole of its 10 µs simulation. By comparing the results with experimental observations, we benchmarked TFE in studying the conformation of membrane and hydrophobic peptides. This work provided accurate results suggesting a methodology to run long MD simulations and predict structural properties of biologically important membrane peptides.


Subject(s)
COVID-19 , Influenza, Human , Humans , Molecular Dynamics Simulation , Peptides/chemistry , Polytetrafluoroethylene , Protein Folding , Protein Structure, Secondary , SARS-CoV-2 , Solvents , Trifluoroethanol/chemistry , Viroporin Proteins , Influenzavirus B , Middle East Respiratory Syndrome Coronavirus
3.
Molecules ; 27(19)2022 Oct 03.
Article in English | MEDLINE | ID: covidwho-2066283

ABSTRACT

Honey inhibits bacterial growth due to the high sugar concentration, hydrogen peroxide generation, and proteinaceous compounds present in it. In this study, the antibacterial activity of stingless and sting honey against foodborne pathogenic bacteria isolated from spoiled milk samples was examined. The isolated bacterial strains were confirmed as Bacillus cereus and Listeriamonocytogenes through morphological, biochemical, and 16 s RNA analysis. Physiochemical characterizations of the honey samples revealed that both of the honey samples had an acidic pH, low water content, moderate reducing sugar content, and higher proline content. Through the disc diffusion method, the antibacterial activities of the samples were assayed and better results were observed for the 50 mg/disc honey. Both stingless and sting honey showed the most positive efficacy against Bacillus cereus. Therefore, an in silico study was conducted against this bacterium with some common compounds of honey. From several retrieved constituents of stingless and sting honey, 2,4-dihydroxy-2,5-dimethyl 3(2H)-furan-3-one (furan) and 4H-pyran-4-one,2,3-dihydro of both samples and beta.-D-glucopyranose from the stingless revealed high ligand-protein binding efficiencies for the target protein (6d5z, hemolysin II). The root-mean-square deviation, solvent-accessible surface area, the radius of gyration, root-mean-square fluctuations, and hydrogen bonds were used to ensure the binding stability of the docked complexes in the atomistic simulation and confirmed their stability. The combined effort of wet and dry lab-based work support, to some extent, that the antimicrobial properties of honey have great potential for application in medicine as well as in the food industries.


Subject(s)
Anti-Infective Agents , Honey , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/analysis , Bacillus cereus , Furans , Hemolysin Proteins , Honey/analysis , Hydrogen Peroxide/pharmacology , Ligands , Microbial Sensitivity Tests , Proline , Pyrans , RNA , Solvents/analysis , Sugars , Water
4.
Sci Rep ; 12(1): 17101, 2022 Oct 12.
Article in English | MEDLINE | ID: covidwho-2062276

ABSTRACT

Chlorella spp., Spirulina spp., and fucoidan dry powders, are commercialized as food supplements and are considered safe for human consumption. Their broad-spectrum antiviral properties have been studied, however, their effect against SARS-CoV-2 remains unknown. We investigated the potential antiviral activity of three algae powders: Chlorella vulgaris, Arthrospira maxima (Spirulina) and fucoidan purified from marine brown algae Sargassum spp. against SARS-CoV-2 infection in vitro. Vero cells were incubated with 70 µg/ml of each algae powder and either 50 or 100 TCID50/ml of SARS-CoV-2, in two types of experiments (pretreatment and simultaneous) and comparing two kinds of solvents (DMEM and DMSO). Chlorella vulgaris powder, inhibited SARS-CoV-2 infection in all assays; viral RNA was significantly reduced in supernatants at 24, 48, 72, and 96 h post-infection, the highest difference in viral load (8000-fold) was observed after 96 h. Arthrospira maxima powder inhibited SARS-CoV-2 infection using 50 TCID50/ml for both experimental schemes, but protection percent was lower when viral inoculum was increase to 100 TCID50/ml; viral RNA decreased 48 h after infection, reaching a 250-fold difference at 72 h. Fucoidan powder partially inhibited SARS-CoV-2 infection since no CPE was observed in 62.5% of trated cultures in DMEM, but the antiviral activity was increased to 100% of protection when DMSO was used as solvent. All the algae samples showed high antiviral activity against SARS-CoV-2 with a SI above of 18. These results suggest that all three algae samples are potential therapeutic candidates for the treatment of COVID-19.


Subject(s)
COVID-19 , Chlorella vulgaris , Animals , Antiviral Agents/pharmacology , COVID-19/drug therapy , Chlorocebus aethiops , Dimethyl Sulfoxide , Humans , Powders , RNA, Viral , SARS-CoV-2 , Solvents , Vero Cells
5.
Acta Chim Slov ; 69(3): 647-656, 2022 Sep 26.
Article in English | MEDLINE | ID: covidwho-2056608

ABSTRACT

These days, the world is facing the threat of pandemic Coronavirus Disease 2019 (COVID-19). Although a vaccine has been found to combat the pandemic, it is essential to find drugs for an effective treatment method against this disease as soon as possible. In this study, electronic and thermodynamic properties, molecular electrostatic potential (MEP) analysis, and frontier molecular orbitals (FMOs) of nine different covid drugs were studied with Density Functional Theory (DFT). In addition, the relationship between the electronic structures of these drugs and their biological effectiveness was examined. All parameters were computed at the B3LYP/6-311++g(d,p) level. The Solvent effect was evaluated using conductor-like polarizable continuum model (CPCM) as the solvation model. It was observed that electrophilic indexes were important to understand the efficiencies of these drugs in COVID-19 disease. Paxlovid, hydroxyquinone, and nitazoxanide were found as the most thermodynamically stable molecules. Thermodynamic parameters also demonstrated that these drugs were more stable in the aqueous media. Global descriptors and the reactivity of these drugs were found to be related. Nitazoxanide molecule exhibited the highest dipole moment. The high dipole moments of drugs can cause hydrophilic interactions that increase their effectiveness in an aqueous solution.


Subject(s)
COVID-19 , Quantum Theory , COVID-19/drug therapy , Electronics , Humans , Models, Molecular , Nitro Compounds , Solvents/chemistry , Thiazoles , Water/chemistry
6.
Chem Pharm Bull (Tokyo) ; 70(10): 679-683, 2022.
Article in English | MEDLINE | ID: covidwho-2054201

ABSTRACT

The liver X receptor is a nuclear hormone receptor that regulates lipid metabolism. Previously, we had demonstrated the antiviral properties of a liver X receptor antagonist associated with the hepatitis C virus and severe acute respiratory syndrome coronavirus 2. In this study, we screened a chemical library and identified two potential liver X receptor antagonists. Spectroscopic analysis revealed that the structures of both antagonists (compounds 1 and 2) were cyclic dimer and trimer of esters, respectively, that consisted of phthalate and 1,6-hexane diol. This study is the first to report the structure of the cyclic trimer of phthalate ester. Further experiments revealed that the compounds were impurities of solvents used for purification, although their source could not be traced. Both phthalate esters exhibited anti-hepatitis C virus activity, whereas the cyclic dimer showed anti-severe acute respiratory syndrome coronavirus 2 activity. Cyclic phthalate derivatives may constitute a novel class of liver X receptor antagonists and broad-spectrum antivirals.


Subject(s)
COVID-19 , Esters , Antiviral Agents/pharmacology , Esters/pharmacology , Hepacivirus , Hexanes , Humans , Liver X Receptors , Phthalic Acids , Receptors, Cytoplasmic and Nuclear , SARS-CoV-2 , Solvents
7.
Int J Mol Sci ; 23(19)2022 Sep 24.
Article in English | MEDLINE | ID: covidwho-2043775

ABSTRACT

In late 2019, a new coronavirus (CoV) caused the outbreak of a deadly respiratory disease, resulting in the COVID-19 pandemic. In view of the ongoing pandemic, there is an immediate need to find drugs to treat patients. SARS-CoV-2 papain-like cysteine protease (PLpro) not only plays an important role in the pathogenesis of the virus but is also a target protein for the development of inhibitor drugs. Therefore, to develop targeted inhibitors, it is necessary to analyse and verify PLpro sites and explore whether there are other cryptic binding pockets with better activity. In this study, first, we detected the site of the whole PLpro protein by sitemap of Schrödinger (version 2018), the cavity of LigBuilder V3, and DeepSite, and roughly judged the possible activated binding site area. Then, we used the mixed solvent dynamics simulation (MixMD) of probe molecules to induce conformational changes in the protein to find the possible cryptic active sites. Finally, the TRAPP method was used to predict the druggability of cryptic pockets and analyse the changes in the physicochemical properties of residues around these sites. This work will help promote the research of SARS-CoV-2 PLpro inhibitors.


Subject(s)
COVID-19 , Papain , Amino Acid Sequence , COVID-19/drug therapy , Coronavirus Papain-Like Proteases , Humans , Pandemics , Papain/metabolism , SARS-CoV-2 , Solvents
8.
Int J Mol Sci ; 23(18)2022 Sep 07.
Article in English | MEDLINE | ID: covidwho-2010122

ABSTRACT

Inhibition of inflammatory responses from the spike glycoprotein of SARS-CoV-2 (Spike) by targeting NLRP3 inflammasome has recently been developed as an alternative form of supportive therapy besides the traditional anti-viral approaches. Clerodendrum petasites S. Moore (C. petasites) is a Thai traditional medicinal plant possessing antipyretic and anti-inflammatory activities. In this study, C. petasites ethanolic root extract (CpEE) underwent solvent-partitioned extraction to obtain the ethyl acetate fraction of C. petasites (CpEA). Subsequently, C. petasites extracts were determined for the flavonoid contents and anti-inflammatory properties against spike induction in the A549 lung cells. According to the HPLC results, CpEA significantly contained higher amounts of hesperidin and hesperetin flavonoids than CpEE (p < 0.05). A549 cells were then pre-treated with either C. petasites extracts or its active flavonoids and were primed with 100 ng/mL of spike S1 subunit (Spike S1) and determined for the anti-inflammatory properties. The results indicate that CpEA (compared with CpEE) and hesperetin (compared with hesperidin) exhibited greater anti-inflammatory properties upon Spike S1 induction through a significant reduction in IL-6, IL-1ß, and IL-18 cytokine releases in A549 cells culture supernatant (p < 0.05). Additionally, CpEA and hesperetin significantly inhibited the Spike S1-induced inflammatory gene expressions (NLRP3, IL-1ß, and IL-18, p < 0.05). Mechanistically, CpEA and hesperetin attenuated inflammasome machinery protein expressions (NLRP3, ASC, and Caspase-1), as well as inactivated the Akt/MAPK/AP-1 pathway. Overall, our findings could provide scientific-based evidence to support the use of C. petasites and hesperetin in the development of supportive therapies for the prevention of COVID-19-related chronic inflammation.


Subject(s)
Antipyretics , COVID-19 , Clerodendrum , Hesperidin , Petasites , A549 Cells , Anti-Inflammatory Agents/pharmacology , COVID-19/drug therapy , Caspase 1/metabolism , Clerodendrum/metabolism , Cytokines/metabolism , Flavonoids/pharmacology , Hesperidin/pharmacology , Humans , Inflammasomes/metabolism , Interleukin-18 , Interleukin-6 , Lung/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Plant Extracts/pharmacology , Proto-Oncogene Proteins c-akt , SARS-CoV-2 , Solvents , Spike Glycoprotein, Coronavirus , Transcription Factor AP-1
9.
Chembiochem ; 23(19): e202200471, 2022 10 06.
Article in English | MEDLINE | ID: covidwho-1990432

ABSTRACT

The 68-kDa homodimeric 3C-like protease of SARS-CoV-2, Mpro (3CLpro /Nsp5), is a key antiviral drug target. NMR spectroscopy of this large system proved challenging and resonance assignments have remained incomplete. Here we present the near-complete (>97 %) backbone assignments of a C145A variant of Mpro (Mpro C145A ) both with, and without, the N-terminal auto-cleavage substrate sequence, in its native homodimeric state. We also present SILLY (Selective Inversion of thioL and Ligand for NOESY), a simple yet effective pseudo-3D NMR experiment that utilizes NOEs to identify interactions between Cys-thiol or aliphatic protons, and their spatially proximate backbone amides in a perdeuterated protein background. High protection against hydrogen exchange is observed for 10 of the 11 thiol groups in Mpro C145A , even those that are partially accessible to solvent. A combination of SILLY methods and high-resolution triple-resonance NMR experiments reveals site-specific interactions between Mpro , its substrate peptides, and other ligands, which present opportunities for competitive binding studies in future drug design efforts.


Subject(s)
COVID-19 , Protons , Amides , Antiviral Agents/chemistry , Coronavirus 3C Proteases , Cysteine Endopeptidases/metabolism , Humans , Ligands , Magnetic Resonance Spectroscopy , Peptides/metabolism , Protease Inhibitors , SARS-CoV-2 , Solvents , Sulfhydryl Compounds
10.
Molecules ; 27(15)2022 Aug 05.
Article in English | MEDLINE | ID: covidwho-1979318

ABSTRACT

Morin (M) is one of the most widely distributed flavonoids with several beneficial effects on human health, and has the potential of being used as a possible treatment for COVID-19. To achieve a better understanding of the process of M dissolution, the fluorescent (FL) emission from M solutions prepared with different polar and nonpolar solvents (methanol, DMSO, and chloroform) was measured and compared with the FL emission from M powder and M crystals. In the FL spectra of the solutions with high M concentration, as well as in the spectra of M in solid state, two features, at 615 nm and 670 nm, were observed. As the solution concentration decreases, the maxima of FL spectra of the M solutions in all considered solvents shift to the blue side of the spectrum until reaching the value of 520 nm. To explain the experimental results, the TDDFT-M06-2X/6-31++G(d,p) method was used to determine the possible electronic transitions in the M molecule. The computations show that the FL emission in the spectral range of detection of our setup (405-800 nm) is related to the excited state intramolecular proton transfer (ESIPT). Comparison of the experimental data with the computations strongly suggests that in low-concentrated solutions, the FL emission is mostly due to electronic transitions in the keto OH3 form, whereas in aggregated states, the dominate contribution to the FL emission spectra is due to the transitions in keto OH5 form. Moreover, the time evolution of the M solutions FL spectra was observed, measured and explained for the first time.


Subject(s)
COVID-19 , Flavonoids , Humans , Models, Molecular , Solvents/chemistry , Spectrometry, Fluorescence
11.
J Pharm Biomed Anal ; 220: 114989, 2022 Oct 25.
Article in English | MEDLINE | ID: covidwho-1977554

ABSTRACT

Morinda citrifolia Linn (noni) is an important plant in the Pacific Asian region. The fruit has been used as a food source and has shown therapeutical benefits for health. Recently, it has become a source for bioactive compounds. In this study, we investigated the antimicrobial and anticancer activities of alcoholic extracts of Hainan dry noni fruit with machinery assistance and identified their novel compounds by UPLC-Q-Exactive Obitrap-MS/MS. By IE extractor aided method, the extraction of both NFE (Noni Fruit Ethanol) and NFM (Noni Fruit Methanol) solvent crude sample extracts were obtained with recovery yields of 98.48% and 71.65%, respectively. The antimicrobial effect of the crude extracts was subjected to disc diffusion test screening against two microbial strains bacterium SA (Staphylococcus aureus) and, fungal CA (Candida albicans). The MIC values of SA and CA were 35.34 and 47.80 mg/mL for NFE, 117.40 and 108.01 mg/mL for NFM, respectively. Further on, cell viability assay showed that IC50 values of extract NFE and NFM on human UMUC-3 bladder carcinogenic cells were 865.1 and 789.1 µg/mL with less effect to human SVHUC-1 normal cell line for 72hr incubation. Using UPLC-Q-exactive Orbitrap-MS/MS, ten compounds were identified in the noni extracts and confirmed from the HMDB and FooDB. Five known bioactive compounds had been used for treatments in anti-cancer, anti-obesity, and Covid-19 patients. The remaining five compounds were found novel in noni fruit. They were Cyanidin 3-(2 G-xylosylrutinoside), Inulobiose, Clausarinol, Pectachol, and 4,7-Megastigmadien-9-ol. The potential bioactivities of these novel compounds will be studied in the near future. These findings form a basis on screening natural medicinal plant extracts for beneficial use as a food and health source.


Subject(s)
Antineoplastic Agents , COVID-19 , Morinda , Anti-Bacterial Agents , Antineoplastic Agents/pharmacology , Ethanol , Fruit , Humans , Methanol , Plant Extracts/pharmacology , Solvents , Tandem Mass Spectrometry
12.
Chemosphere ; 303(Pt 3): 135186, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-1866965

ABSTRACT

Globally, an estimated 130 billion face masks are used and disposed of every month. Thus, recycling or upcycling discarded face masks has attracted significant attention due to economic benefits and environmental concerns. To reduce the amount of used face masks going to waste, this study features a superhydrophobic face mask prepared by simple chemical modification with environmentally preferable alkane solvents (n-hexane, n-heptane, and n-decane), that is effective as a sorbent for oil spill cleanup. All alkanes examined increased the surface roughness of the face masks and improved face mask hydrophobicity. The heptane treated face mask (at 90 °C for 1 h), can adsorbed Arabian light crude oil up to 21 times of their weight on the water surface. In addition, chloroform, toluene, gasoline, and diesel were adsorbed 18, 13, 8 and 16 times, respectively. More importantly, heptane has a high recycling efficiency as a treatment solvent and is reusable for at least 10 cycles of mask surface treatment. Consequently, this inexpensive and easily fabricated material is a promising development in waste face mask (WFM) upcycling.


Subject(s)
Petroleum Pollution , Water Pollutants, Chemical , Heptanes , Hydrophobic and Hydrophilic Interactions , Masks , Petroleum Pollution/prevention & control , Polypropylenes , Solvents , Water Pollutants, Chemical/analysis
13.
Int J Environ Res Public Health ; 19(9)2022 05 09.
Article in English | MEDLINE | ID: covidwho-1847326

ABSTRACT

Hospital workers have increased exposure risk of healthcare-associated infections due to the frontline nature of their work. Olfactory dysfunction is highly prevalent. The objectives for this investigation are to study the prevalence of long-lasting olfactory dysfunction associated with COVID-19 infection in hospital workers during the first pandemic wave, to identify clinical characteristics and associated symptomatology, and to analyze how many patients with COVID-19 infection had developed olfactory dysfunction during infection and maintained a reduced olfactory function for approximately 10 weeks after diagnosis. Between June and July of 2020, a cross-sectional study was carried out at the Hospital Central de la Cruz Roja San José and Santa Adela in Madrid, Spain. One hundred sixty-four participants were included, of which 110 were patient-facing healthcare staff and 54 were non-patient-facing healthcare staff. Participants were split into three groups, according to COVID-19 diagnosis and presence of COVID-19 related olfactory symptomatology. Participants were asked to complete a structured online questionnaire along with Sniffin' Stick Olfactory Test measurements. In this study, 88 participants were confirmed for COVID-19 infection, 59 of those participants also reported olfactory symptomatology. The prevalence of COVID-19 infection was 11.35%, and the prevalence for olfactory dysfunction was 67.05%. Olfactory dysfunction associated with COVID-19 infection leads to long-lasting olfactory loss. Objective assessment with Sniffin' Stick Olfactory Test points to odor identification as the most affected process. Lemon, liquorice, solvent, and rose are the odors that are worst recognized. Mint, banana, solvent, garlic, coffee, and pineapple, although they are identified, are perceived with less intensity. The findings of this study confirmed a high prevalence of SARS-CoV-2 infection among the hospital workers.


Subject(s)
COVID-19 , Olfaction Disorders , COVID-19/epidemiology , COVID-19 Testing , Cross-Sectional Studies , Hospitals , Humans , Odorants , Olfaction Disorders/diagnosis , Olfaction Disorders/epidemiology , Olfaction Disorders/etiology , Prevalence , SARS-CoV-2 , Smell , Solvents
14.
Sci Total Environ ; 836: 155611, 2022 Aug 25.
Article in English | MEDLINE | ID: covidwho-1815158

ABSTRACT

This study monitors the presence of 88 volatile organic compounds (VOCs) and semi-volatile organic compounds (semi-VOCs) at the gas phase of seven indoor settings in a school in the city of Tarragona, Spain, and five outdoor locations around the city. The VOCs and semi-VOCs monitored were solvents (∑Solvents), aldehydes (∑Aldehydes), emerging organic compounds (∑EOCs), and other VOCs and semi-VOCs (∑Others). Passive sampling campaigns were performed using Carbopack X tubes followed by thermal desorption coupled to gas chromatography with mass spectrometry (TD-GC-MS). Overall, 70 of the target compounds included in the method were determined in the indoor air samples analysed, and 42 VOCs and semi-VOCs in the outdoor air samples. Our results showed that solvents were ubiquitous throughout the school at concentrations ranging from 272 µg m-3 to 423 µg m-3 and representing 68%-83% of total target compounds (∑Total). The values of ∑Total in 2021 were three times as high as those observed at the same indoor settings in 2019, with solvents experiencing the greatest increase. A plausible explanation for these observations is the implementation of anti-COVID-19 measures in the indoor settings, such as the intensification of cleaning activities and the use of hydroalcoholic gels as personal hygiene. The ∑Total values observed in the indoor settings evaluated were twenty times higher than those found outdoors. ∑Solvents were the most representative compounds found indoors (74% of the ∑Total). The concentrations of VOCs and semi-VOCs observed in the outdoors were strictly related to combustion processes from automobile traffic and industrial activities, with ∑Others contributing 58%, ∑Solvents 31%, and ∑Aldehydes 11% of the ∑Total. EOCs, on the other hand, were not detected in any outdoor sample.


Subject(s)
Air Pollutants , Air Pollution, Indoor , Air Pollution , Volatile Organic Compounds , Air Pollutants/analysis , Air Pollution/analysis , Air Pollution, Indoor/analysis , Aldehydes/analysis , Environmental Monitoring/methods , Gas Chromatography-Mass Spectrometry , Solvents/analysis , Volatile Organic Compounds/analysis
15.
Rapid Commun Mass Spectrom ; 36(12): e9282, 2022 Jun 30.
Article in English | MEDLINE | ID: covidwho-1802571

ABSTRACT

RATIONALE: A derivatization switchable solvent liquid-liquid microextraction quadruple isotope dilution gas chromatography mass spectrometry (D-SS-LLME-ID4 -GC/MS) method is presented for the determination of hydroxychloroquine sulfate in human biofluids. METHODS: While mixing type/period and concentration of NaOH were optimized via a univariate optimization approach, a multivariate optimization approach was used to determine optimum values for relatively more important parameters such as volumes of derivatization agent (acetic anhydride), NaOH and switchable solvent. RESULTS: Under the optimum experimental conditions, limit of detection and limit of quantification were calculated as 0.03 and 0.09 mg/kg (mass based), respectively. An isotopically labelled material (hydroxychloroquine methyl acetate-d3 ) was firstly synthesized to be used in ID4 experiments which give highly accurate and precise recovery results. After the application of D-SS-LLME-ID4 , superior percent recovery results were recorded as 99.9 ± 1.6-101.3 ± 1.2 for human serum, 99.9 ± 1.7-99.8 ± 1.8 for urine and 99.6 ± 1.5-101.0 ± 1.1 for saliva samples. CONCLUSIONS: The developed D-SS-LLME-ID4 -GC/MS method compensates the complicated matrix effects of human biofluids and provides highly accurate quantification of an analyte with precise results.


Subject(s)
Liquid Phase Microextraction , Acetates , Gas Chromatography-Mass Spectrometry/methods , Humans , Hydroxychloroquine , Isotopes , Limit of Detection , Liquid Phase Microextraction/methods , Sodium Hydroxide , Solvents/chemistry
16.
Molecules ; 27(7)2022 Mar 31.
Article in English | MEDLINE | ID: covidwho-1785840

ABSTRACT

The simultaneous effects of three continuous factors: solvent concentration (50-100%), treated times (25-85 min), treated temperatures (25-55 °C), and two categorical factors: type of solvents (methanol or ethanol) and ultrasonic frequency (28 kHz or 40 kHz) on ultrasonic-assisted extraction yield from waste orange peels were evaluated and optimized by response surface methodology. Fourier Transform Infrared (FTIR) spectroscopy with a wavelength of 500 cm-1 to 4000 cm-1 was employed to rapidly identify the orange extracts. The significant polynomial regression models on crude extraction, sediments after evaporation, and precipitation yield were established (p < 0.05). Results revealed that solvent concentration affected crude extraction and precipitation yield linearly (p < 0.01). The optimal and practical ultrasound-assisted extraction conditions for increasing the precipitation yield were using 61.42% methanol with 85 min at 55 °C under 40 kHz ultrasonic frequency. The spectra of extracts showed a similar fingerprint of hesperidin.


Subject(s)
Citrus sinensis , Antioxidants/chemistry , Citrus sinensis/chemistry , Methanol , Plant Extracts/chemistry , Solvents/chemistry
17.
Huan Jing Ke Xue ; 43(4): 1747-1755, 2022 Apr 08.
Article in Chinese | MEDLINE | ID: covidwho-1776689

ABSTRACT

Volatile organic compounds (VOCs) are the key precursors of the ozone (O3) formation processes in the troposphere and are important control objects for the coordinated governance of O3 and PM2.5. The Spring Festival of 2020 was affected by the novel coronavirus (COVID-19) pneumonia epidemic:companies stopped work and production, and traffic was restricted, providing scientific experimentation opportunities for pollutant emission reduction research. This study analyzed the variety of the composition, chemical reaction activity, and sources of VOCs in the Pearl River Delta during the Spring Festival and the epidemic control period, using real-time online monitoring data of VOCs obtained at four sites(Guangzhou, Dongguan, Zhongshan, and Duanfen)in the Pearl River Delta from January 1, 2020 to February 29, 2020. The results showed that during the Spring Festival and the epidemic control period, the average of φ (VOCs) in the Pearl River Delta was 15.89×10-9, and the maximum hourly average concentration was 45.43×10-9, values that were 44% and 60% lower, respectively, than those before the Spring Festival holiday. Among the VOCs component concentration decreases, the aromatic hydrocarbon component decreased the most, and the decrease in the urban area of the Pearl River Delta (74%) was significantly greater than that in the suburban area (56%). As a result, the contribution rate of aromatic hydrocarbons to the total VOCs was reduced to less than 10%. The analysis of the·OH reaction activity of VOCs(L·OH)and ozone formation potential(OFP)showed that the L·OH and OFP of VOCs decreased significantly in the Pearl River Delta during the Spring Festival and the epidemic control period. Compared with those before the Spring Festival holiday, the total L·OH and total OFP decreased by an average of 60% and 63% in the urban area of the Pearl River Delta, respectively. Additionally, the atmospheric oxidation had also been significantly reduced, which showed a 28% decrease in ρ(Ox). The ratio of toluene/benzene showed that the influence of industrial sources had almost disappeared during the Spring Festival and the epidemic control period, and the total points of the representative components of industrial-related solvent-use sources such as toluene, ethylbenzene, and m/p-xylene dropped by 72% to 91%. The results of this study suggest that solvent-use sources and vehicle exhaust emission sources are the current sources of VOCs that need to be paid attention to in the prevention and control of O3 pollution in the Pearl River Delta region, and the impact of petrochemical sources cannot be ignored in the work of further reducing the background concentration of O3.


Subject(s)
Air Pollutants , COVID-19 , Ozone , Volatile Organic Compounds , Air Pollutants/analysis , COVID-19/epidemiology , COVID-19/prevention & control , China/epidemiology , Environmental Monitoring/methods , Holidays , Humans , Ozone/analysis , Solvents/analysis , Toluene/analysis , Vehicle Emissions/analysis , Volatile Organic Compounds/analysis
18.
Int J Med Mushrooms ; 23(12): 15-28, 2021.
Article in English | MEDLINE | ID: covidwho-1775507

ABSTRACT

A significant knowledge gap currently exists in the literature on the emerging interventions and bioactivity of aqueous extracts of mushrooms. Different solvents and techniques used in the extraction of mushroom metabolites have been discussed. Here, data obtained were analyzed using Microsoft Excel and presented in charts. The results showed that methanol was the most commonly reported extraction solvent (29.70%), followed by water (26.73%). Extracted metabolites of mushrooms were mostly reported for their antioxidant activity (33%). Investigations on the use of mushroom metabolites to treat tropical diseases, their application in novel coronavirus disease-COVID 19 management, and other beneficial effects (antiplasmodial, antimalarial, antityrosinase, analgesic, anticoagulation, and antiasthmatic) on health are emerging and reported rarely to date. It is a notable conclusion that water extracts from mushrooms are effective in the treatment of diverse health conditions, however, further studies are necessary. Modern water extraction techniques are essential for better yield and process optimization but are currently less applied and less frequently reported.


Subject(s)
Agaricales , COVID-19 , Antioxidants/pharmacology , COVID-19/drug therapy , Humans , Plant Extracts/pharmacology , Solvents , Water
19.
Nat Methods ; 19(4): 479-485, 2022 04.
Article in English | MEDLINE | ID: covidwho-1764194

ABSTRACT

The recent development of solvent- and polymer-based brain-clearing techniques has advanced our ability to visualize the mammalian nervous system in three dimensions. However, it remains challenging to image the mammalian body en bloc. Here we developed HYBRiD (hydrogel-based reinforcement of three-dimensional imaging solvent-cleared organs (DISCO)), by recombining components of organic- and polymer-based clearing pipelines. We achieved high transparency and protein retention, as well as compatibility with direct fluorescent imaging and immunostaining in cleared mammalian bodies. Using parvalbumin- and somatostatin-Cre models, we demonstrated the utility of HYBRiD for whole-body imaging of genetically encoded fluorescent reporters without antibody enhancement of signals in newborn and juvenile mice. Using K18-hACE2 transgenic mice, HYBRiD enabled perfusion-free clearing and visualization of SARS-CoV-2 infection in a whole mouse chest, revealing macroscopic and microscopic features of viral pathology in the same sample. HYBRiD offers a simple and universal solution to visualize large heterogeneous body parts or entire animals for basic and translational research.


Subject(s)
COVID-19 , Hydrogels , Animals , Imaging, Three-Dimensional/methods , Mammals , Mice , Polymers , SARS-CoV-2 , Solvents
20.
Mol Divers ; 26(5): 2613-2629, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-1616204

ABSTRACT

Several existing drugs have gained initial consideration due to their therapeutic characteristics against COVID-19 (Corona Virus Disease 2019). Hydroxychloroquine (HCQ) was proposed as possible therapy for shortening the duration of COVID-19, but soon after this, it was discarded. Similarly, known antiviral compounds were also proposed and investigated to treat COVID-19. We report a pharmacophore screening using essential chemical groups derived from HCQ and known antivirals to search a natural compound chemical space. Molecular docking of HCQ under physiological condition with spike protein, 3C-like protease (3CLpro), and RNA-dependent RNA polymerase (RdRp) of SARS-CoV2 showed - 8.52 kcal/mole binding score with RdRp, while the other two proteins showed relatively weaker binding affinity. Docked complex of RdRp-HCQ is further examined using 100 ns molecular dynamic simulation. Docking and simulation study confirmed active chemical moieties of HCQ, treated as 6-point pharmacophore to screen ZINC natural compound database. Pharmacophore screening resulted in the identification of potent hit molecule [(3S,3aR,6R,6aS)-3-(5-phenylsulfanyltetrazol-1-yl)-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-6-yl]N-naphthalen-ylcarbamate from natural compound library. Additionally, a set of antiviral compounds with similar chemical scaffolds are also used to design a separate ligand-based pharmacophore screening. Antiviral pharmacophore screening produced a potent hit 4-[(1,5-dimethyl-3-oxo-2-phenylpyrazol-4-yl)-(2-hydroxyphenyl)methyl]-1,5-dimethyl-2-phenylpyrazol-3-one containing essential moieties that showed affinity towards RdRp. Further, both these screened compounds are docked (- 8.69 and - 8.86 kcal/mol) and simulated with RdRp protein for 100 ns in explicit solvent medium. They bind at the active site of RdRp and form direct/indirect interaction with ASP618, ASP760, and ASP761 catalytic residues of the protein. Successively, their molecular mechanics Poisson Boltzmann surface area (MMPBSA) binding energies are calculated over the simulation trajectory to determine the dynamic atomistic interaction details. Overall, this study proposes two key natural chemical moieties: (a) tetrazol and (b) phenylpyrazol that can be investigated as a potential chemical group to design inhibitors against SARS-CoV2 RdRp.


Subject(s)
COVID-19 , RNA-Dependent RNA Polymerase , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Furans , Humans , Hydroxychloroquine , Ligands , Molecular Docking Simulation , Molecular Dynamics Simulation , Peptide Hydrolases/metabolism , RNA, Viral , SARS-CoV-2 , Solvents , Spike Glycoprotein, Coronavirus , Zinc
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