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1.
J Ethnopharmacol ; 319(Pt 3): 117362, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38380575

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Colorectal cancer (CRC) remains a significant global health concern, and targeting inflammation has emerged as a promising approach for its prevention and treatment. Medicinal plants and phytochemicals have garnered attention for their potential efficacy against inflammation with minimal toxicity. Osmanthus fragrans var. aurantiacus Makino (O. fragrans) has a history of traditional use in Korea and China in treating various inflammation-related conditions, but its potential use for CRC has not been uncovered. AIM OF THE STUDY: This study aims to explore the potential anti-proliferative and pro-apoptotic properties of O. fragrans, focusing on its impact on CRC treatment. By investigating O. fragrans, we aim to uncover its anti-proliferative and apoptotic effects in human CRC cells, potentially paving the way for effective and well-tolerated therapeutic strategies for CRC patients. MATERIALS AND METHODS: Ethanol (EtOH) extracts of O. fragrans leaf and flower, along with specific fractions (n-hexane, ethyl acetate (EtOAc), n-butanol, and the aqueous residue) were evaluated for their anti-proliferative effects in human CRC cells using MTT assays, and compared to normal colon cells. Mechanistic insights and chemical profiling were obtained through flow cytometry, colorimetric assays, western blotting, and molecular docking, and high-performance liquid chromatography (HPLC) system. RESULTS: Both flower and leaf EtOH extracts of O. fragrans exhibited significant anti-proliferative effects in human CRC cells, with the leaf extract demonstrating higher potency. The EtOAc fraction from the leaf extract displayed the strongest anti-CRC cell proliferative effects while no cytotoxic effects in normal colon cells. Chemical profiling of these fractions identified triterpenoids as significant components in the EtOAc fractions. The leaf EtOAc fraction caused cell cycle arrest and apoptosis, accompanied by elevating intracellular reactive oxygen species and mitochondrial dysfunction in CRC cells. Additionally, it inhibited NF-κB and ERK1/2 signaling, leading to reduced COX2 expression. Notably, two triterpenoids isolated from the leaf EtOAc fraction, maslinic acid and corosolic acid, displayed potent anti-cancer activity in CRC cells without affecting normal colon cells. Corosolic acid exhibited a strong binding affinity to COX2 and reduced its expression, supporting its role in the anti-inflammatory and anti-cancer effects. CONCLUSIONS: Our findings suggest that O. fragrans, particularly its triterpenoid-rich EtOAc fraction, holds promise as a novel therapeutic agent for CRC prevention and therapy. These results provide valuable insights into the potential application of O. fragrans and its bioactive compounds in combating CRC.


Assuntos
Acetatos , Neoplasias Colorretais , Triterpenos , Humanos , NF-kappa B , Extratos Vegetais/uso terapêutico , Ciclo-Oxigenase 2 , Simulação de Acoplamento Molecular , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Inflamação/tratamento farmacológico , Etanol/farmacologia , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico
2.
J Biomed Mater Res A ; 112(5): 743-753, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38071731

RESUMO

Sulfur quantum dots (SQDs) are attracting increasing attention in the biomedical field due to their unique properties, such as antibacterial activity, free radical scavenging potential, optical properties, biocompatibility, and non-toxicity. Ethylenediamine passivated SQDs (ED-SQDs) were synthesized using a hydrothermal method. Cytotoxicity evaluation of ED-SQDs on RAW264.7 cells showed more than 90% cell viability even at 500 µg/mL of ED-SQDs, with an established IC50 value of 880.9 µg/mL. In addition, ED-SQDs showed potent antioxidant activity in vitro, effectively scavenging ABTS and DPPH free radicals at concentrations below 100 µg/mL, comparable to ascorbic acid. ED-SQD reduced lipopolysaccharide (LPS)-induced nitric oxide and reactive oxygen species in macrophages, lowered pro-inflammatory cytokines, and inactivated LPS-activated STAT3. In addition, ED-SQD increased nuclear NRF2 and the expression of genes encoding antioxidant enzymes in LPS-stimulated cells. These results reveal the antioxidant and anti-inflammatory potential of ED-SQDs at non-toxic concentrations, providing evidence for their potential anti-inflammatory applications.


Assuntos
Antioxidantes , Pontos Quânticos , Antioxidantes/farmacologia , Antioxidantes/química , Lipopolissacarídeos/farmacologia , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química
3.
Antioxidants (Basel) ; 12(9)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37759996

RESUMO

Excessive oxidative stress and inflammatory responses are associated with the development of various diseases, including cancer. Glucosinolates (GSLs) are phytochemicals known for their antioxidant properties, and doubled haploid lines (DHLs) of Brassica rapa with high GSL contents (HGSL) were intentionally developed from two edible subspecies of Brassica rapa: B. rapa subsp. trilocularis and B. rapa subsp. chinensis. The purpose of the present study is to assess the capacity of HGSL DHLs to mitigate oxidative stress and inflammation in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, compared to pak choi as a parental control. Our findings demonstrate that HGSL DH lines effectively suppressed the expression of inducible nitric oxide synthase, leading to the reduced levels of nitric oxide at non-toxic concentrations. Additionally, these lines exhibited scavenging activity against reactive oxygen species and free radicals. The enhanced antioxidant capacity of HGSL DHLs was mechanistically attributed to the upregulation of antioxidant enzymes, such as NADPH quinone oxidoreductase 1 (NQO1), the glutamate-cysteine ligase catalytic subunit (GCLC), and heme oxygenase-1 (HMOX1). Furthermore, we confirmed that these effects were mediated through the nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathway via p38 phosphorylation. Moreover, HGSL DHLs demonstrated inhibitory effects on pro-inflammatory cytokines and signal transducers and activators of transcription 3 (STAT3) phosphorylation. Collectively, our results indicate that HGSL DHLs possess better antioxidant and anti-inflammatory properties compared to the parental control pak choi in LPS-stimulated RAW264.7 cells, suggesting that HGSL DHLs of Brassica rapa could be considered as a beneficial daily vegetable for reducing the risk of inflammation-associated diseases.

4.
Brain Struct Funct ; 228(7): 1629-1641, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37421418

RESUMO

Astrocyte elevated gene-1 (AEG-1) is a well-known oncogene implicated in various types of human cancers, including brain tumors. Recently, AEG-1 has also been reported to play pivotal roles in glioma-associated neurodegeneration and neurodegenerative diseases like Parkinson's disease and amyotrophic lateral sclerosis. However, the normal physiological functions and expression patterns of AEG-1 in the brain are not well understood. In this study, we investigated the expression patterns of AEG-1 in the normal mouse brain and found that AEG-1 is widely expressed in neurons and neuronal precursor cells, but little in glial cells. We observed differential expression levels of AEG-1 in various brain regions, and its expression was mainly localized in the cell body of neurons rather than the nucleus. Additionally, AEG-1 was expressed in the cytoplasm of Purkinje cells in both the mouse and human cerebellum, suggesting its potential role in this brain region. These findings suggest that AEG-1 may have important functions in normal brain physiology and warrant further investigation. Our results may also shed light on the differential expression patterns of AEG-1 in normal and pathological brains, providing insights into its roles in various neurological disorders.


Assuntos
Encéfalo , Proteínas de Membrana , Animais , Humanos , Camundongos , Encéfalo/metabolismo , Neoplasias Encefálicas/patologia , Moléculas de Adesão Celular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
5.
Phytochemistry ; 210: 113649, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36963708

RESUMO

Three undescribed iridoid glucosides and nine known compounds were isolated from Vitex rotundifolia L. f. Their structural elucidation was performed based on their spectroscopic data or acid hydrolysis followed by HPLC analysis and comparison of their NMR data with those reported in the literature. These iridoids were then evaluated for inflammatory effects through inhibition on NO production level in LPS-stimulated RAW264.7 cells. The active compounds, rotundifoliin C, isonishindacin A, agnuside, and eurostoside, were further investigated for their anti-inflammatory mechanisms of action on expression levels of iNOS and COX-2 proteins. In addition, V. rotundifolia fractions also significantly inhibited LPS-induced IL-8 production, with IC50 values ranging from 9.81 to 54.31 µg/mL. Rotundifoliin A, agnuside, VR-I (10-O-vanilloyl aucubin), and eurostoside showed inhibition rates of 55.5%, 94.6%, 55.6%, and 81.9% on IL-8 production at concentrations of 100 µM, respectively, compared to those of control without sample addition. The therapeutic properties of the plant might give rise to develop the functional products to treat inflammatory diseases.


Assuntos
Iridoides , Vitex , Iridoides/farmacologia , Iridoides/química , Vitex/química , Lipopolissacarídeos/farmacologia , Interleucina-8 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química
6.
Metabolites ; 13(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36837867

RESUMO

The objective of this study is to describe the separation and identification of one new phenolic and 19 known compounds from Vitex rotundifolia. Their structures were determined based on spectroscopic (NMR, CD, and MS) data analysis or Mosher's method, and were compared with those reported in the literature. These isolates were then evaluated for their anti-inflammatory and antioxidant activities based on the inhibition of nitric oxide (NO) and interleukin (IL)-8 production in lipopolysaccharide (LPS)-stimulated cells (RAW264.7 and HT-29) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging abilities, respectively. In the NO assay, compounds 12-14 showed strong inhibition with compounds 10 and 15 displaying significant inhibition. In the IL-8 assay, compounds 8, 9, 13, 14, 19, and 20 exhibited potential to inhibit IL-8 production and other compounds displayed moderate inhibition. An in silico docking approach also revealed strong binding affinities for protein-ligand complexes of these active compounds against IL-8 production. The docking results were correlated with the experimental data of the IL-8 assay. Thus, these active compounds should be considered as candidates for further in vivo studies. This study implies the potential of new and active chemicals isolated from V. rotundifolia and provides evidence to support the development of active fractions and constituents into functional products targeting inflammatory diseases the future.

7.
Nat Prod Res ; : 1-6, 2023 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-36800928

RESUMO

The concern about the quality of medicinal herbs is becoming important due to the poor quality of commercial products like cosmetics, functional foods, and natural medicine produced from them. However, there is a lack of modern analytical methods to evaluate the constituents of P. macrophyllus until the moment. This paper reports an analytical method based on UHPLC-DAD and UHPLC-MS/MS MRM methods to evaluate the ethanolic extracts of P. macrophyllus leaves and twigs. 15 main constituents were identified using a UHPLC-DAD-ESI-MS/MS profiling. Subsequently, a reliable analytical method was established and successfully used to quantitate the constituent's content using four marker compounds in leaf and twig extracts of this plant. The result obtained from the current study demonstrated the secondary metabolites and the variety of their derivatives in this plant. The analytical method can help evaluate the quality of P. macrophyllus and develop high-value functional materials.

8.
Int Immunopharmacol ; 115: 109610, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36571918

RESUMO

Ilex rotunda Thunb. has been used in traditional medicine for treating rheumatoid arthritis, relieving pain and indigestion. In the present study, we isolated three new caffeic acid benzyl ester (CABE) analogs (1-3) along with eight known compounds (4-11) from the extract of I. rotunda. The absolute configuration of α-hydoxycarboxylic acid in 1 was assigned with the phenylglycine methyl ester (PGME) method. We further investigated their anti-inflammatory activities in lipopolysaccharide (LPS)-induced macrophages (RAW 264.7) cells. Among them, compounds 2-4, 7, 8, 10, and 11 suppressed the production of nitric oxide (NO), pro-inflammatory mediators. It was additionally confirmed that the anti-inflammatory effect of active compound 2 was through significant suppression of cytokines, including interleukin (IL)-6, IL-1ß, tumor necrosis factor (TNF)-α, and IL-8 in LPS-stimulated RAW 264.7 cells and colon epithelial (HT-29) cells. Western blot analysis revealed that compound 2 decreased the LPS-induced expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), and phosphorylated extracellular regulated kinase (pERK)1/2. The following molecular docking simulations showed the significant interactions of compound 2 with the iNOS protein. These results suggested that the compound 2 can be used as potential candidate for treating inflammatory diseases such as inflammatory bowel disease (IBD).


Assuntos
Ilex , NF-kappa B , Animais , Camundongos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Ilex/metabolismo , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células RAW 264.7 , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ciclo-Oxigenase 2/metabolismo
9.
Antioxidants (Basel) ; 11(12)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36552671

RESUMO

Chemoprevention is a method of health control in modern industrialized societies. Traditional breeding (hybridization) has been widely used to produce new (sub)species with beneficial phenotypes. Previously, we produced a number of doubled haploid (DH) lines of Brassica rapa with a high glucosinolate (GSL) content. In this study, we evaluated the anticancer activities of extracts from three selected high-GSL (HGSL)-containing DH lines (DHLs) of Brassica rapa in human colorectal cancer (CRC) cells. The three HGSL DHL extracts showed anti-proliferative activities in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay and pro-apoptotic activities in the cell cycle or annexin V analysis with the induction of pro-apoptotic protein expression in CRC cells. Mechanistically, HGSL DHL extracts inhibited the NF-κB and ERK pathways, leading to a reduction in the nuclear localization of NF-κB p65. In addition, reactive oxygen species were induced by HGSL DHL extract treatment in CRC cells. In conclusion, our data suggest that the newly developed HGSL DHLs possess enhanced anticancer activities and are potentially helpful as a daily vegetable supplement with chemopreventive activities.

10.
Int J Mol Sci ; 23(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36499154

RESUMO

Colorectal cancer (CRC) is an inflammation-associated common cancer worldwide. Paejang-san and Mori Cortex Radicis have been traditionally used for treating intestinal inflammatory diseases in Korea and China. In the present study, we developed a new herbal formula as an alternative to CRC treatments, which is composed of two main components of Paejangsan (Patriniae Radix (Paejang in Korean) and Coix Seed (Yiyiin in Korean)), and Mori Cortex Radicis (Sangbekpi in Korean) based on the addition and subtraction theory in traditional medicine, hence the name PSY, and explored the potential therapeutic effects of the new formula PSY in human CRC cells by analyzing viability, cell cycle and apoptosis. We found that PSY ethanol extract (EtOH-Ex), but not water extract, significantly suppressed the viability of human CRC cells, and synergistically decreased the cell proliferation compared to each treatment of Patriniae Radix and Coix Seed extract (PY) or Mori Cortex Radicis extract (S), suggesting the combination of PY and S in a 10-to-3 ratio for the formula PSY. PSY EtOH-Ex in the combination ratio reduced cell viability but induced cell cycle arrest at the G2/M and sub-G1 phases as well as apoptosis in CRC cells. In addition, the experimental results of Western blotting, immunofluorescence staining and reporter assays showed that PSY also inhibited STAT3 by reducing its phosphorylation and nuclear localization, which resulted in lowering STAT3-mediated transcriptional activation. In addition, PSY regulated upstream signaling molecules of STAT3 by inactivating JAK2 and Src and increasing SHP1. Moreover, the chemical profiles of PSY from UPLC-ESI-QTOF MS/MS analysis revealed 38 phytochemicals, including seven organic acids, eight iridoids, two lignans, twelve prenylflavonoids, eight fatty acids, and one carbohydrate. Furthermore, 21 potentially bioactive compounds were highly enriched in the PSY EtOH-Ex compared to the water extract. Together, these results indicate that PSY suppresses the proliferation of CRC cells by inhibiting the STAT3 signaling pathway, suggesting PSY as a potential therapeutic agent for treating CRC and 21 EtOH-Ex-enriched phytochemicals as anti-cancer drug candidates which may act by inhibiting STAT3.


Assuntos
Neoplasias Colorretais , Espectrometria de Massas em Tandem , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Antineoplásicos Fitogênicos/farmacologia
11.
Cancers (Basel) ; 14(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36358633

RESUMO

Triple-negative breast cancer (TNBC) remains as an intractable malignancy with limited therapeutic targets. High expression of epidermal growth factor receptor (EGFR) has been associated with a poor prognosis of TNBC; however, EGFR targeting has failed with unfavorable clinical outcomes. Here, we performed a combinatorial screening of fifty-five protein kinase inhibitors with the EGFR inhibitor gefitinib in the TNBC cell line MDA-MB-231 and identified the IκB kinase (IKK) inhibitor IKK16 as a sensitizer of gefitinib. Cell viability and clonogenic survival assays were performed to evaluate the antiproliferative effects of the gefitinib and IKK16 (Gefitinib + IKK16) combination in TNBC cell lines. Western blot analyses were also performed to reveal the potential mode of action of this combination. In addition, next-generation sequencing (NGS) analysis was performed in Gefitinib+IKK16-treated cells. The Gefitinib+IKK16 treatment synergistically reduced cell viability and colony formation of TNBC cell lines such as HS578T, MDA-MB-231, and MDA-MB-468. This combination downregulated p-STAT3, p-AKT, p-mTOR, p-GSK3ß, and p-RPS6. In addition, p-NF-κB and the total NF-κB were also regulated by this combination. Furthermore, NGS analysis revealed that NF-κB/RELA targets including CCL2, CXCL8, EDN1, IL-1ß, IL-6, and SERPINE1 were further reduced and several potential tumor suppressors, such as FABP3, FADS2, FDFT1, SEMA6A, and PCK2, were synergistically induced by the Gefitinib-+IKK16 treatment. Taken together, we identified the IKK/NF-κB pathway as a potential target in combination of EGFR inhibition for treating TNBC.

12.
Antioxidants (Basel) ; 11(10)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36290712

RESUMO

Ilex rotunda Thunb., has been used to treat common cold, tonsillitis, and eczema. It is also a source of antioxidants. However, information regarding its antioxidative phytochemical composition is still incomplete and limited. In this present study, we initially determined DPPH radical scavenging activity of the extracts of I. rotunda fruits, twigs, and leaves. Among them, the twig extract exhibited a potential of antioxidant capacity. Based on antioxidant effect guided experiments, extraction condition using 80% EtOH was then optimized. DPPH and ABTS radical scavenging assays were also performed for fractions. The n-butanol fraction showed the highest antioxidant effect. Using chromatographic methods, eight marker compounds (1-8) were further isolated. Their structures were determined by spectroscopic and mass data. Method validation was employed to quantitate contents of these eight marker compounds. Subsequently, the HPLC-DPPH method was used to evaluate the contribution of certain compounds to total antioxidant activity of the extract. Lastly, parallel artificial membrane permeability assay for blood-brain barrier (PAMPA-BBB) was applied to investigate brain-penetrable antioxidants from I. rotunda extract. As a result, compound 7 (4,5-dicaffeoylquinic acid) showed significant antioxidant activity and penetration across the BBB via transcellular passive diffusion. Our findings suggested that compound 7 can be used as a therapeutic potential candidate in natural product-based central nervous system (CNS) drug discovery.

13.
Healthcare (Basel) ; 10(4)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35455819

RESUMO

This study integrates two competing views to examine whether medical doctors are satisfied with their jobs when they perceive their hospitals as being oriented toward profit (i.e., rational choice theory) or purpose (i.e., public service motivation). Using a sample of 127 doctors from 70 hospitals, this study tests these competing views. The results show that doctors who perceive their hospitals as purpose-driven are likely to experience job satisfaction, and this pattern still holds even if they also perceive their hospitals to be emphasizing profits. However, only the purpose-driven orientation results in job satisfaction via a sense of meaningfulness. Thus, this study offers comprehensive evidence that while medical doctors are likely to be satisfied with their jobs when they work at either purpose-driven or profit-driven hospitals, only purpose-driven hospitals give doctors a sense of meaningfulness. This finding suggests that both rational choice theory and public service motivation perspective are valid; however, public service motivation plays a greater role in terms of a sense of meaningfulness. Theoretical contributions and practical implications are discussed.

14.
Antioxidants (Basel) ; 11(3)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35326104

RESUMO

An extraction method using 80% EtOH was selected and applied to obtain the total extracts from leaves, flowers, fruits, twigs, and roots of Vitex rotundifolia L.f. based on the antioxidant activity-guided experiments. Subsequently, total extract from each part of V. rotundifolia was successfully partitioned into fractions, which were evaluated for their antioxidant and anti-inflammatory properties via DPPH, ABTS, and NO assays, respectively. Among them, EtOAc (E) and n-butanol (B) fractions showed the potent antioxidant activity and the methylene chloride (MC) fractions of roots, leaves, and fruits that exhibited strong scavenging activity on DPPH and ABTS radicals. In the anti-inflammatory assay, n-hexane (H) and MC fractions of leaves potently inhibited NO production in LPS-stimulated RAW264.7 cells, followed by E fractions derived from fruits, flowers, twigs, and roots, along with B fractions from flowers and twigs. Additionally, a comprehensive HPLC-decoupled MS profiling was established and validated using seven isolated marker compounds (1-7), which were identified by analysis of their UV, NMR, and MS data. The established method was also applied for quantification of these marker compounds in each organ collected from different locations, and to assess their antioxidant capacity by a screening DPPH-HPLC method. Principal component analysis suggested the botanical organs from this plant correlated with the marker compound contents in association with bioactivity. The study results are a prelude to further studies involving the active fractions and provide a comprehensive insight into the functional products of this plant against oxidative diseases.

15.
Antioxidants (Basel) ; 10(12)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34942995

RESUMO

Abnormal inflammation and oxidative stress are involved in various diseases. Papaver rhoeas L. possesses various pharmacological activities, and a previously reported analysis of the anti-inflammatory effect of P. nudicaule ethanol extracts and alkaloid profiles of the plants suggest isoquinoline alkaloids as potential pharmacologically active compounds. Here, we investigated anti-inflammatory and antioxidant activities of ethyl acetate (EtOAc) fractions of P. nudicaule and P. rhoeas extracts in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. EtOAc fractions of P. nudicaule and P. rhoeas compared to their ethanol extracts showed less toxicity but more inhibitory activity against LPS-induced nitric oxide production. Moreover, EtOAc fractions lowered the LPS-induced production of proinflammatory molecules and cytokines and inhibited LPS-activated STAT3 and NF-κB, and additionally showed significant free radical scavenging activity and decreased LPS-induced reactive oxygen species and oxidized glutathione. EtOAc fractions of P. nudicaule increased the expression of HO-1, GCLC, NQO-1, and Nrf2 in LPS-stimulated cells and that of P. rhoeas enhanced NQO-1. Furthermore, metabolomic and biochemometric analyses of ethanol extracts and EtOAc fractions indicated that EtOAc fractions of P. nudicaule and P. rhoeas have potent anti-inflammatory and antioxidant activities, further suggesting that alkaloids in EtOAc fractions are potent active molecules of tested plants.

16.
Sci Total Environ ; 748: 141360, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32827892

RESUMO

The impact of the Teflon reactor wall on secondary organic aerosol (SOA) formation was explicitly simulated by using the Unified Partitioning Aerosol Phase Reaction (UNIPAR) model integrated with gas-wall partitioning (GWP). The formation of oxygenated semivolatile organic compounds (SVOCs) from the photooxidation of hydrocarbons (HC) was simulated by using an explicit gas-kinetic mechanism (MCM V3.3.1). In the model, SVOC's GWP and gas-particle partitioning onto preexisting particulate matter were kinetically treated with the absorption and desorption processes. The UNIPAR model streamlined aerosol growth via the oligomerization of reactive SVOCs in the organic phase and aqueous reactions in the inorganic phase. Two important GWP parameters, GWP coefficient (Kw, i) and the deposition rate constant (k_onw, i) of SVOCs (i) to the wall were predicted by using a quantitative structure activity relationship (QSAR) employing SVOCs' physicochemical descriptors. This GWP model was then incorporated with the UNIPAR model in the DSMACC-KPP platform and simulated SOA chamber data. The three different HCs (toluene, 1,3,5-trimethylbenzene, and α-pinene) were photochemically oxidized in the presence of NOx and inorganic seed aerosols in an outdoor photochemical smog chamber (UF-APHOR). The impact of GWP on SOA mass varied ranging from 9% to 71% with HCs, seed conditions, NOx, and temperature. Toluene SOA in the absence of inorganic aerosol was the most sensitive to GWP. However, in the presence of wet-inorganic seed, the impact of GWP on SOA was smaller than that of non-seed SOA owing to rapid reactions of organic species in the aqueous phase. SOA mass can be significantly underestimated in the absence of wet-inorganic seed when the aerosol model employs parameters derived using SOA data with GWP artifacts.

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