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1.
Food Res Int ; 187: 114330, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763633

RESUMO

Processing technology plays a crucial role in the formation of tea aroma. The dynamic variations in volatile metabolites across different processing stages of fresh scent green tea (FSGT) were meticulously tracked utilizing advanced analytical techniques such as GC-E-Nose, GC-MS, and GC × GC-TOFMS. A total of 244 volatile metabolites were identified by GC-MS and GC × GC-TOFMS, among which 37 volatile compounds were concurrently detected by both methods. Spreading and fixation stages were deemed as pivotal processes for shaping the volatile profiles in FSGT. Notably, linalool, heptanal, 2-pentylfuran, nonanal, ß-myrcene, hexanal, 2-heptanone, pentanal, 1-octen-3-ol, and 1-octanol were highlighted as primary contributors to the aroma profiles of FSGT by combining odor activity value assessment. Furthermore, lipid degradation and glycoside hydrolysis were the main pathways for aroma formation of FSGT. The results not only elucidate the intricate variations in volatile metabolites but also offer valuable insights into enhancing the processing techniques for improved aroma quality of green tea.


Assuntos
Manipulação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Chá , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Chá/química , Manipulação de Alimentos/métodos , Nariz Eletrônico , Aldeídos/análise , Aldeídos/metabolismo , Monoterpenos Acíclicos/metabolismo , Monoterpenos Acíclicos/análise , Camellia sinensis/química , Camellia sinensis/metabolismo , Cetonas/análise , Cetonas/metabolismo , Octanóis
2.
Food Res Int ; 187: 114398, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763656

RESUMO

Nowadays, it is important to monitor the freshness of meat during storage to protect consumers' health. Volatile organic compounds (VOCs) are responsible for odour and taste of food, and they give an indication about meat quality and freshness. This study had the aim to seek and select potential new markers of meat spoilage through a semi-quantitative analysis in five types of meat (beef, raw and baked ham, pork sausage and chicken) and then to develop a new quantitative analytical method to detect and quantify potential markers on five types of meat simultaneously. Firstly, a new headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) method was developed to evaluate the volatile profile of five types of meat, preserved at 4 °C for 5 days. Among the 40 compounds identified, 15 were chosen and selected as potential shelf-life markers on the basis of their presence in most of meat samples or/and for their constant increasing/decreasing trend within the sample. Afterwards, a quantitative HS-SPME-GC-MS analytical method was developed to confirm which VOCs can be considered markers of shelf-life for these meat products, stored at 4 °C for 12 days. Some of the compounds analyzed attracted attention as they can be considered markers of shelf-life for at least 4 types of meat: 1-butanol, 3-methylbutanol, 1-hexanol, 2-nonanone, nonanal, 1-octen-3-ol and linalool. In conclusion, in this study a new quantitative HS-SPME-GC-MS analytical method to quantity 15 VOCs in five types of meat was developed and it was demonstrated that some of the compounds quantified can be considered markers of shelf-life for some of the meat products analyzed.


Assuntos
Armazenamento de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Produtos da Carne , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Produtos da Carne/análise , Animais , Suínos , Odorantes/análise , Bovinos , Aldeídos/análise , Galinhas , Cetonas/análise , Pentanóis/análise , Monoterpenos Acíclicos/análise , Octanóis
3.
J Chromatogr A ; 1721: 464850, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38564932

RESUMO

The solvation parameter model uses five system independent descriptors to characterize compound properties defined as excess molar refraction, E, dipolarity/polarizability, S, hydrogen-bond acidity, A, hydrogen-bond basicity, B, and McGowan's characteristic volume, V, to model transfer properties between condensed phases. The V descriptor is assigned from structure. For compounds liquid at 20 °C the E descriptor can be assigned from the characteristic volume and its refractive index. The E descriptor for compounds solid at 20 °C and the S, A, and B descriptors are experimental properties traditionally assigned from chromatographic, liquid-liquid partition, and solubility measurements. In this report liquid-liquid partition constants in totally organic and aqueous biphasic systems are evaluated as a standalone technique for descriptor assignments. Using six totally organic biphasic systems the S, A, and B descriptors were assigned with an average absolute deviation (AAD) of about 0.04, 0.03, and 0.04, respectively, compared with the best estimate of the true descriptor values for 65 compounds. The E descriptor for compounds solid at 20 °C can only be estimated with an AAD of approximately 0.1. For six aqueous biphasic systems the B descriptor is assigned with a lower AAD of 0.028 and higher AAD of 0.08 and 0.05 for the S and A descriptors, respectively, than for the totally organic biphasic systems for compounds with a reliable value for the E descriptor. The preferred system for descriptor assignments utilizes both totally organic biphasic systems (heptane-1,1,1-trifluoroethanol, isopentyl ether-propylene carbonate, isopentyl ether-ethanolamine, heptane-ethylene glycol, heptane-formamide, and 1,2-dichloroethane-ethylene glycol) and aqueous biphasic systems (octanol-water, cyclohexane-water) with the possible substitution of some systems with alternative systems of similar selectivity. For 55 varied compounds this combination of eight organic and aqueous biphasic systems resulted in an AAD of approximately 0.03, 0.02, and 0.02 for the S, A, and B descriptors compared to the best estimate of the true descriptor value. For 30 compounds solid at 20 °C the AAD for the E descriptor of 0.11 is poorly assigned. The relative average absolute deviation in percent (RAAD) corresponds to 9.7 %, 3.1 %. 4.0 % and 8.3 % for E, S, A, and B, respectively, for the eight biphasic systems. Liquid-liquid partition is compared to reversed-phase liquid and gas chromatography as a standalone technique for descriptor assignments.


Assuntos
Éteres , Água , Etilenoglicóis , Heptanos/química , Hidrogênio , Água/química , Cicloexanos/química , Octanóis/química
4.
Analyst ; 149(8): 2363-2373, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38454902

RESUMO

This paper describes the electrochemical behavior of five ß-blockers at the polarized liquid-liquid interface formed between aqueous solution (sodium chloride solution or Britton-Robinson buffers) and bis(triphenylphosphoranylidene)ammonium tetrakis(4-chlorophenyl)borate (BTPPATPBCl) dissolved in 1,2-dichloroethane (the organic phase). All measurements reported in this work were conducted using cyclic voltammetry (CV). The effects of the concentration of analytes, the pH of the aqueous phase, and applied electrochemical parameters on the analytical performance of the studied system are studied and discussed. The linear dynamic ranges (LDRs) of the studied ß-blockers were in the range of 5-200 µmol L-1 and the lowest limit of detection (LOD) value was determined for pindolol (LOD = 1.96 µM µmol L-1). The highest LOD value was 4.96 µmol L-1 found for nebivolol. In addition, physicochemical parameters such as the formal Galvani potential difference (Δaqorgϕ), formal Gibbs free energies of the ion transfer reaction (ΔaqorgG') and partition coefficients (log P'aq/org) for all studied molecules were determined. The latter were compared and correlated with the available literature values of log Poctanol. Finally, a standard addition method was used to determine the concentration of nebivolol in pharmaceutical preparations using a platform based on the electrified liquid-liquid interface.


Assuntos
Pindolol , Água , Nebivolol , Octanóis , Água/química , Boratos
5.
J Toxicol Sci ; 49(4): 127-137, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556350

RESUMO

The octanol/water partition coefficient P (logP) is a hydrophobicity index and is one of the determining factors for the pharmacokinetics of orally administered substances because it influences membrane permeability. To illustrate the wide-ranging variety of compounds in the chemical space, a two-dimensional data plot consisting of 25 blocks was previously proposed based on a substance's in silico chemical descriptors. The logP values of approximately 200 diverse chemicals (test plus reference compounds covering all 25 blocks of the chemical space) were estimated experimentally using retention times in reverse-phase liquid chromatography; these values were compared with those of authentic reference compounds with established logP values (available for 17 of 60 reference substances in the Organization for Economic Co-operation and Development Test Guideline 117). The logP values of 140 of 165 chemicals successfully estimated using four different mobile phase conditions (pH 2, 4, 7, and 10 for molecular forms) correlated significantly with those calculated using the in silico packages ChemDraw and ACD/Percepta (r > 0.72). Although substances that neighbored authentic compounds in the chemical space had precisely correlated logP values estimated experimentally and in silico, some compounds that were more distant from authentic substances showed lower logP values than those estimated in silico. These results indicate that additional authentic reference materials with wider ranging chemical diversity and their logP values from reverse-phase liquid chromatography should be included in the international test guidance to promote simple and reliable estimation of octanol/water partition coefficients, which are important determinant factors for the pharmacokinetics of general chemicals.


Assuntos
Cromatografia de Fase Reversa , Água , Cromatografia de Fase Reversa/métodos , Água/química , Octanóis/química , Interações Hidrofóbicas e Hidrofílicas , Cromatografia Líquida de Alta Pressão/métodos
6.
Int J Mol Sci ; 25(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38396923

RESUMO

The epidermis serves as a protective barrier against external threats and is primarily composed of keratinocytes, which ultimately form corneocytes. Involucrin, a protein integral to the cornified envelope, plays a pivotal role in preserving the functional integrity of the skin barrier. Previous studies have shown that Akt plays an important role in keratinocyte differentiation and skin barrier development. This study investigated whether dihydromyrcenol (DHM), a plant-derived terpene, could increase involucrin production in keratinocytes and sought to elucidate the possible underlying mechanisms. To accomplish this objective, we assessed the alterations in involucrin by DHM through quantitative PCR and Western blot on the HaCaT cell line. The changes in the promoter levels were investigated using luciferase assays. Furthermore, upstream mechanisms were explored through the use of siRNA and inhibitors. To strengthen our findings, the results were subsequently validated in primary cells and 3D skin equivalents. DHM significantly increased involucrin mRNA and protein levels in a concentration-dependent manner. In addition, the Fyn-Akt signaling pathway was found to be required for DHM-induced involucrin expression, as inhibition of Fyn or Akt blocked the increase in involucrin mRNA induced by DHM. The transcription factor Sp1, which is recognized as one of the transcription factors for involucrin, was observed to be activated in response to DHM treatment. Moreover, DHM increased epidermal thickness in a 3D human skin model. These findings suggest that the modulation of involucrin expression with DHM could improve skin barrier function and highlight the importance of manipulating the Akt pathway to achieve this improvement.


Assuntos
Queratinócitos , Monoterpenos , Octanóis , Precursores de Proteínas , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Queratinócitos/metabolismo , Diferenciação Celular/genética , Transdução de Sinais , RNA Mensageiro/metabolismo
7.
Sci Total Environ ; 918: 170562, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38307293

RESUMO

The often-overlooked importance of foliar absorption on the plant uptake of organic pollutants was investigated by an exposure chamber test. Rice seedlings were exposed to organophosphate esters (OPEs) through 8 scenarios arranged from 3 major uptake pathways: root uptake via solution, foliar uptake via gas, and foliar uptake via particles, to identify the contributions of these 3 uptake pathways and their influences on the translocation and metabolism of OPEs in rice. The concentration of OPEs in rice tissues showed an "additive effect" with the increase of exposure pathways. OPEs in rice shoots mainly originated from foliar uptake through particle (29.6 %-63.5 %) and gaseous (28.5 %-49.4 %) absorptions rather than root uptake (7.86 %-24.2 %) under the exposure condition. In comparison with stomal absorption, wax layer penetration was the main pathway for most OPEs to enter into leaves, especially for those compounds with high octanol-air partition coefficients. Although the subcellular distributions of OPEs in the rice tissues of the foliar exposure were slightly different from those of the root exposure, hydrophobic OPEs were mainly stored in the cell wall with hydrophilic OPEs mainly in the cytosol. The translocation of OPEs from the exposed tissue to the unexposed tissue were significantly negatively correlated with their octanol-water partition coefficients, but their basipetal translocation were limited. The result suggested that the translocation of OPEs within rice is prioritized over their degradation. This study deepens our understanding of the processes behind OPE uptake by rice and highlights the importance of foliar uptake, especially for those via particle absorption.


Assuntos
Poluentes Ambientais , Retardadores de Chama , Oryza , Oryza/metabolismo , Transporte Biológico , Poluentes Ambientais/metabolismo , Organofosfatos/metabolismo , Octanóis/metabolismo , Ésteres/metabolismo , Retardadores de Chama/análise , Monitoramento Ambiental , China
8.
J Food Sci ; 89(3): 1554-1566, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38317380

RESUMO

The Maillard reaction (MR) of tilapia byproduct protein hydrolysates was investigated for the use of byproduct protein as a food ingredient and to mask its fishy odor and bitter flavor. The flavor differences in tilapia byproduct hydrolysates before and after the MR were analyzed to explore the key flavor precursor peptides and amino acids involved in MR. The results suggested that eight key volatile substances, including 2,5-dimethylpyrazine, 2-pentylfuran, hexanal, octanal, nonanal, (E)-2-decenal, decanal, and 1-octen-3-ol contributed most to the MR products group (ROAV > 1). Ten volatile compounds, including 1-octen-3-ol, hexanal, 2-pentylfuran, 2,5-dimethylpyrazine, methyl decanoate, and 2-octylfuran, were the flavor markers that distinguished the different samples (VIP > 1). The four most consumed peptides were VAPEEHPTL, GPIGPRGPAG, KSADDIKKAF, and VWEGQNIVK. Umami peptides and bitter free amino acids (FAAs) were the key flavor precursor peptide and FAAs, respectively. Overall, the hydrolysates of tilapia byproducts with flavor improved by MR are a promising strategy for the production of flavorings.


Assuntos
Aldeídos , Reação de Maillard , Octanóis , Tilápia , Animais , Cromatografia Gasosa-Espectrometria de Massas , Aminoácidos , Peptídeos
9.
Environ Sci Process Impacts ; 26(3): 510-518, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38329481

RESUMO

Using glancing-angle laser-induced fluorescence (GALIF) spectroscopy as a probe, the partitioning of naphthalene, fluoranthene, pyrene, umbelliferone, phenol red, and bisphenol A from bulk solution to the air-water interface was examined in both pure water and aqueous solutions of 6 mM octanol. Previous studies provided similar Langmuir adsorption isotherms for anthracene and imidazole 2-carboxaldehyde. The surface partitioning behaviour of each compound in both environments was well described using a Langmuir adsorption model; partitioning coefficients were derived from the fits to such isotherms. Only the PAH molecules, naphthalene, fluoranthene and pyrene, saw an enhancement in the surface partitioning in octanol solution compared to pure water. The surface partitioning to pure water surfaces could be fairly well described using a one parameter linear free energy relationship based on either solubility or KOW.


Assuntos
Poluentes Ambientais , Fluorenos , Água , Água/química , Pirenos , Octanóis , Naftalenos , Adsorção
10.
J Hazard Mater ; 467: 133663, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38325095

RESUMO

Incorporating spent coffee grounds into single-use drinking straws for enhanced biodegradability also raises safety concerns due to increased chemical complexity. Here, volatile organic compounds (VOCs) present in coffee ground straws (CGS), polylactic acid straws (PLAS), and polypropylene straws (PPS) were characterized using headspace - solid-phase microextraction and migration assays, by which 430 and 153 VOCs of 10 chemical categories were identified by gas chromatography - mass spectrometry, respectively. Further, the VOCs were assessed for potential genetic toxicity by quantitative structure-activity relationship profiling and estimated daily intake (EDI) calculation, revealing that the VOCs identified in the CGS generally triggered the most structural alerts of genetic toxicity, and the EDIs of 37.9% of which exceeded the threshold of 0.15 µg person-1 d-1, also outnumbering that of the PLAS and PPS. Finally, 14 VOCs were prioritized due to their definite hazards, and generally higher EDIs or detection frequencies in the CGS. Meanwhile, the probability of producing safer CGS was also illustrated. Moreover, it was uncovered by chemical space that the VOCs with higher risk potentials tended to gather in the region defined by the molecular descriptor related to electronegativity or octanol/water partition coefficient. Our results provided valuable references to improve the chemical safety of the CGS, to promote consumer health, and to advance the sustainable development of food contact materials.


Assuntos
Café , Compostos Orgânicos Voláteis , Humanos , Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Octanóis , Polipropilenos
11.
Chemosphere ; 350: 141086, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38163464

RESUMO

The rising demand from consumer goods and pharmaceutical industry is driving a fast expansion of newly developed chemicals. The conventional toxicity testing of unknown chemicals is expensive, time-consuming, and raises ethical concerns. The quantitative structure-property relationship (QSPR) is an efficient computational method because it saves time, resources, and animal experimentation. Advances in machine learning have improved chemical analysis in QSPR studies, but the real-world application of machine learning-based QSPR studies was limited by the unexplainable 'black box' feature of the machine learnings. In this study, multi-encoder structure-to-toxicity (S2T)-transformer based QSPR model was developed to estimate the properties of polychlorinated biphenyls (PCBs) and endocrine disrupting chemicals (EDCs). Simplified molecular input line entry systems (SMILES) and molecular descriptors calculated by the Dragon 6 software, were simultaneously considered as input of QSPR model. Furthermore, an attention-based framework is proposed to describe the relationship between the molecular structure and toxicity of hazardous chemicals. The S2T-transformer model achieved the highest R2 scores of 0.918, 0.856, and 0.907 for logarithm of octanol-water partition coefficient (Log KOW), octanol-air partition coefficient (Log KOA), and bioconcentration factor (Log BCF) estimation of PCBs, respectively. Moreover, the attention weights were able to properly interpret the lateral (meta, para) chlorination associated with PCBs toxicity and environmental impact.


Assuntos
Bifenilos Policlorados , Animais , Bifenilos Policlorados/análise , Octanóis/química , Água/química , Software , Relação Quantitativa Estrutura-Atividade , Meio Ambiente
12.
Insect Biochem Mol Biol ; 167: 104069, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38220070

RESUMO

The host-seeking behavior of mosquitoes have long been established to be primarily odor-mediated. In this process, olfactory receptors (Ors) play a critical role. 1-Octen-3-ol is a common volatile compound that is attractive to hematophagous arthropods such as mosquitos. The olfactory receptor 8 (AaOr8) on the tip of the stylet and maxillary palp of Aedes aegypti is tuned to 1-octen-3-ol, which is required for mosquitoes to quickly find blood vessels from a vertebrate host. However, little is known about the interaction of AaOr8 with 1-octen-3-ol which was studied in vivo and in silico in this study. The molecular binding poses and energies between ligands and the receptor were investigated. Three mutants of AaOr8 were cloned and compared with in vivo calcium imaging utilizing heterologous expression systems. As a result, our findings imply that a genetic disruption including targeted modification of Ors genes may be used to reduce mosquito bites.


Assuntos
Aedes , Neurônios Receptores Olfatórios , Receptores Odorantes , Animais , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Aedes/metabolismo , Neurônios Receptores Olfatórios/metabolismo , Octanóis/química
13.
J Hazard Mater ; 466: 133543, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38262318

RESUMO

The prevalence of organophosphate esters (OPEs) in the global environment is increasing, which aligns with the decline in the usage of polybrominated diphenyl ethers (PBDEs). PBDEs, a category of flame retardants, were banned and classified as persistent organic pollutants (POPs) through the Stockholm Convention due to their toxic and persistent properties. Despite a lack of comprehensive understanding of their ecological and health consequences, OPEs were adopted as replacements for PBDEs. This research aims to offer a comparative assessment of PBDEs and OPEs in various domains, specifically focusing on their persistence, bioaccumulation, and toxicity (PBT) properties. This study explored physicochemical properties (such as molecular weight, octanol-water partition coefficient, octanol-air partition coefficient, Henry's law constant, and vapor pressures), environmental behaviors, global concentrations in environmental matrices (air, water, and soil), toxicities, bioaccumulation, and trophic transfer mechanisms of both groups of compounds. Based on the comparison and analysis of environmental and toxicological data, we evaluate whether OPEs represent another instance of regrettable substitution and global contamination as much as PBDEs. Our findings indicate that the physical and chemical characteristics, environmental behaviors, and global concentrations of PBDEs and OPEs, are similar and overlap in many instances. Notably, OPE concentrations have even surged by orders of several magnitude compared to PBDEs in certain pristine regions like the Arctic and Antarctic, implying long-range transport. In many instances, air and water concentrations of OPEs have been increased than PBDEs. While the bioaccumulation factors (BAFs) of PBDEs (ranging from 4.8 to 7.5) are slightly elevated compared to OPEs (-0.5 to 5.36) in aquatic environments, both groups of compounds exhibit BAF values beyond the threshold of 5000 L/kg (log10 BAF > 3.7). Similarly, the trophic magnification factors (TMFs) for PBDEs (ranging from 0.39 to 4.44) slightly surpass those for OPEs (ranging from 1.06 to 3.5) in all cases. Metabolic biotransformation rates (LogKM) and hydrophobicity are potentially major factors deciding their trophic magnification potential. However, many compounds of PBDEs and OPEs show TMF values higher than 1, indicating biomagnification potential. Collectively, all data suggest that PBDEs and OPEs have the potential to bioaccumulate and transfer through the food chain. OPEs and PBDEs present a myriad of toxicity endpoints, with notable overlaps encompassing reproductive issues, oxidative stress, developmental defects, liver dysfunction, DNA damage, neurological toxicity, reproductive anomalies, carcinogenic effects, and behavior changes. Based on our investigation and comparative analysis, we conclude that substituting PBDEs with OPEs is regrettable based on PBT properties, underscoring the urgency for policy reforms and effective management strategies. Addressing this predicament before an exacerbation of global contamination is imperative.


Assuntos
Retardadores de Chama , Éteres Difenil Halogenados , Éteres Difenil Halogenados/toxicidade , Éteres Difenil Halogenados/análise , Monitoramento Ambiental , Organofosfatos/análise , Água/análise , Retardadores de Chama/toxicidade , Retardadores de Chama/análise , Octanóis , Ésteres/toxicidade
14.
Talanta ; 271: 125696, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38290267

RESUMO

Five in vitro physicochemical systems have been evaluated in terms of its ability to emulate the skin permeation of neutral compounds: the permeation in two different PAMPA membranes, the classical octanol-water partition coefficient, and two biomimetic chromatography systems, one based in cerasome electrokinetic chromatography and another based in reversed-phase liquid chromatography measurements. The coefficients of the solvation parameter model equation of the mentioned systems have been compared to the ones of the skin permeation process through different comparison parameters. Moreover, a method to predict whether a physicochemical system is able to emulate satisfactorily a biological one, just by the analysis of the equation coefficients has been developed. Results reveal that the two PAMPA systems are a good choice to emulate directly the skin permeation of neutral compounds. Instead, the other three systems need a volume correction term to provide a satisfactory emulation. However, after the correction, all the evaluated systems show a similar ability to emulate well skin permeation, as predicted.


Assuntos
Biomimética , Pele , Água/química , Octanóis/química , Cromatografia de Fase Reversa
15.
Expert Rev Anti Infect Ther ; 22(4): 253-272, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37461145

RESUMO

BACKGROUND: Based on gas chromatography - mass spectrometry (GC-MS) results of a previous study, six metabolites including alpha-terpineol, geranyl acetate, linalool, myrcenol, terpinolene, and thymol showed significantly higher amounts relative to other metabolites. METHODS: A continuation of the previous study, the interaction of these metabolites with the main virulence factors of P. aeruginosa (pseudomonas elastase and exotoxin A), Staphylococcus aureus (alpha-hemolysin and protein 2a), Mycobacterium tuberculosis (ESX-secreted protein B and the serine/threonine protein kinase), and Escherichia coli (heat-labile enterotoxin and Shiga toxin) were evaluated by molecular docking study and molecular simulation. RESULTS: In the case of Shiga toxin, higher and lower binding affinities were related to alpha-terpinolene and zincite with values of -5.8 and -2.6 kcal/mol, respectively. For alpha-hemolysin, terpinolene and alpha-terpinolene demonstrated higher binding affinities with similar energies of -5.9 kcal/mol. Thymol and geranyl acetate showed lower binding energy of -5.7 kcal/mol toward protein 2a. Furthermore, thymol had a higher binding affinity toward heat-labile enterotoxin and ESX-secreted protein B with values of -5.9 and -6.1 kcal/mol, respectively. CONCLUSIONS: It is concluded that the availability of secondary metabolites of A. haussknechtii surrounding zinc oxide (ZnO) NPs can hinder P. aeruginosa by inactivating Pseudomonas elastase and exotoxin.


Assuntos
Acetatos , Monoterpenos Acíclicos , Monoterpenos Cicloexânicos , Monoterpenos , Mycobacterium tuberculosis , Octanóis , Infecções Estafilocócicas , Humanos , Timol/química , Staphylococcus aureus , Pseudomonas aeruginosa , Simulação de Acoplamento Molecular , Fatores de Virulência , Escherichia coli , Proteínas Hemolisinas , Enterotoxinas , Exotoxinas , Toxinas Shiga , Elastase Pancreática
19.
ChemMedChem ; 19(5): e202300395, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37986275

RESUMO

An ab initio conformational analysis of oral beyond Rule of 5 (bRo5) drugs was complemented with measured permeability and logP(octanol) to derive design principles conferring oral bioavailability. 3D polar surface area (PSA) thresholds for oral bRo5 drugs coincided with those reported for Ro5 space. The majority of oral bRo5 drugs exceeded the Ro5 logP threshold of 5, reflecting a bias for permeability. Above 500 Da molecular weight (MW), oral drugs and highly permeable Novartis compounds occupy a narrow polarity range (topological or TPSA/MW) of 0.1-0.3 Å2 /Da, whose upper half coincides with the lower 90 percentiles of the Novartis logP set. This TPSA/MW range and 3D PSA below 100 Å2 define the "Rule of ~1 /5" for balancing lipophilicity and permeability. Neutral TPSA, defined as TPSA minus 3D PSA occurs independent of conformation, intramolecular hydrogen bonds (IMHB) and MW, suggesting it is an intrinsic molecular property. Neutral TPSA increased in the lead optimization (LO) campaigns of three first in class de novo designed bRo5 drugs and may be a useful design parameter in bRo5 space.


Assuntos
Disponibilidade Biológica , Ligação de Hidrogênio , Peso Molecular , Octanóis , Permeabilidade
20.
Environ Toxicol Chem ; 43(1): 42-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37818875

RESUMO

The bioaccumulation behavior, including the uptake, internal distribution, depuration, and biotransformation rates, of three widely used linear methyl-siloxanes was investigated in rainbow trout. Dietary uptake efficiencies of octamethyltrisiloxane (L3), decamethyltetrasiloxane (L4), and dodecamethylpentasiloxane (L5) were 15% (3.3% standard error [SE]), 8.6% (1.4% SE), and 15% (1.8% SE), respectively, and for L3 and L4 were well below those of nonmetabolizable reference chemicals with similar octanol-water partition coefficients, suggesting significant intestinal biotransformation of L3 and L4. Somatic biotransformation rate constants were 0.024 (0.003 SE) day-1 for L3 and 0.0045 (0.0053 SE) day-1 for L4 and could not be determined for L5. Lipid-normalized biomagnification factors for L3, L4, and L5 were 0.24 (0.02 SE), 0.24 (0.01 SE), and 0.62 (0.05 SE) kg-lipid kg-lipid-1 , respectively. Bioconcentration factors standardized to a 5% lipid content fish for water in Canadian oligotrophic lakes with a dissolved organic carbon content of 7.1 mg L-1 were 2787 (354 SE) for L3, 2689 (312 SE) for L4, and 1705 (418 SE) L kg-wet weight-1 , respectively, and 3085 (392 SE) for L3, 4227 (490 SE) for L4, and 3831 (938 SE) L kg-wet weight-1 in water with a dissolved organic carbon content of 2.0 mg L-1 . A comparison of 238 bioaccumulation profiles for 166 different chemicals shows that the bioaccumulation profiles for L3, L4, and L5 are vastly different from those of other very hydrophobic compounds found in the environment. Environ Toxicol Chem 2024;43:42-51. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Oncorhynchus mykiss , Poluentes Químicos da Água , Animais , Bioacumulação , Siloxanas/análise , Siloxanas/metabolismo , Matéria Orgânica Dissolvida , Canadá , Oncorhynchus mykiss/metabolismo , Poluentes Químicos da Água/análise , Água/metabolismo , Octanóis/metabolismo
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