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1.
Anal Chem ; 96(25): 10111-10115, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38869290

RESUMO

The Si window is the most widely used internal reflection element (IRE) for electrochemical attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), yet local chemical etching on Si by concentrated OH- anions bottlenecks the reliable application of this method in strong alkaline electrolytes. In this report, atomic layer deposition of a 25 nm nonconductive TiO2 barrier layer on the reflecting plane of a Si prism is demonstrated to address this challenge. In situ ATR-SEIRAS measurement on a Au film electrode with the Si/TiO2 composite IRE in 1 M NaOH reveals reversible global spectral features without spectral distortion at 1000-1300 cm-1, in stark contrast to those obtained with a bare Si window. By applying this structured ATR-SEIRAS, ethanol electrooxidation on a Pt/C catalyst in 1 and 5 M NaOH is explored, manifesting that such high pH values prevent the adsorption of as-formed acetate in the C2 pathway but not that of CO intermediate in the C1 pathway.

2.
ACS Appl Mater Interfaces ; 16(24): 31114-31125, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38857487

RESUMO

Albeit the undesirable attributes of NiOx, such as low conductivity, unmanageable defects, and redox reactions occurring at the perovskite/NiOx interface, which impede the progress in inverted perovskite solar cells (i-PSCs), it is the most favorable choice of technology for industrialization of PSCs. In this study, we propose a novel Ni vacancy defect modulate approach to leverage the conformal growth and surface self-limiting reaction characteristics of the atomic layer deposition (ALD)-fabricated NiOx by varying the O2 plasma injection time (tOE) to induce self-doping. Consequently, NiOx thin films with enhanced conductivity, an appropriate Ni3+/Ni2+ ratio, stable surface states, and ultrathinness are realized as hole-transporting layers (HTLs) in p-i-n PSCs. As a result of these improvements, ALD-NiOx-based devices exhibit the highest power conversion efficiency (PCE) of 19.86% and a fill factor (FF) of 81.86%. Notably, the optimal interfacial defects effectively suppressed the severe reaction between the perovskite and NiOx. This suppression is evidenced by the lowest decay rate observed in a harsh environment, lasting for 500 consecutive hours. The proposed approach introduces the possibility of a hierarchical distribution of defects and offers feasibility for the fabrication of large-area, uniform, and high-quality films.

3.
Am J Chin Med ; 51(8): 2095-2120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37865870

RESUMO

[Formula: see text]-Escin is an oleanane-type pentacyclic triterpenoid saponin extracted from the seeds of Aesculus hippocastanum (AH), which is more widely distributed. [Formula: see text]-Escin sodium has been approved by the American FDA for clinical usage. This paper is intended to summarize an updated and comprehensive review of the pharmacological activities, pharmacokinetic properties, toxicity, and analytical methods of [Formula: see text]-escin. Studies have shown that [Formula: see text]-escin has significant antitumor, antiviral, anti-inflammatory, and other activities alongside less adverse effects and higher safety than other compounds. The review shows that the pharmacological effects of [Formula: see text]-escin involve mechanisms such as ATM/[Formula: see text]H2AX, RhoA/Rock, GSK-3[Formula: see text]/[Formula: see text]-Catenin, HER2/HER3/Akt, and PI3K/Akt signaling pathways, and Cyclin A, p21[Formula: see text], survivin, Bcl-2, Mcl-1, Caspases, TGF-[Formula: see text], MMPs, and TNF-[Formula: see text] among other inflammatory factors. [Formula: see text]-Escin has significant cytotoxicity; the use of the chitosan/xanthan gum-based polyelectrolyte complexes PA1 and PC-11 to modify it not only to reduces its toxicity, but also improves its drug efficacy. Because of this, these compounds may become a new research hotspot. [Formula: see text]-Escin in vivo metabolism can be converted by the CYP1A2 enzyme in the intestinal flora to produce [Formula: see text]-escin, deacylated, deglycosylated, and 21[Formula: see text]-[Formula: see text]-crotonoyl-protoescin, and the binding rate of the plasma proteins is higher than 90%. These are mainly metabolized by the liver, kidneys, and other organs, and excreted in the form of urine and feces. The number of reports on the specific mediators of the metabolism of [Formula: see text]-escin and their mechanisms and metabolites is relatively small; furthermore, the results are vague. Therefore, a complete and in-depth exploration of the pharmacokinetic characteristics of [Formula: see text]-escin is needed to provide a more complete and effective theoretical reference for the study of its pharmacodynamic activity.


Assuntos
Escina , Extratos Vegetais , Escina/farmacologia , Extratos Vegetais/farmacologia , Quinase 3 da Glicogênio Sintase , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt
4.
Front Pharmacol ; 14: 1164784, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37649892

RESUMO

Enterovirus 71 (EV71) commonly causes symptoms such as hand, foot, and mouth disease (HFMD) in infants and children and may lead to neurological disease and even death in severe cases. Appropriate vaccines for the prevention of HFMD are available in the clinic; however, they present different and serious adverse effects that cannot guarantee compliance and efficacy. The purpose of this study was to analyze the potential mechanism of Bryum billardieri Schwaegr. (BBS) against EV71 and analyze its potential active components. A previous in vitro antiviral assay was used to determine the best extraction method for the active site of BBS against EV71, and the results showed that the antiviral activity of BBS was more pronounced in the fraction that was extracted by aqueous extraction and alcoholic precipitation and then obtained by purification on a silica gel column (dichloromethane:methanol = 0:100). In addition, the therapeutic effects of BBS on EV71-infected mice were further investigated by in vivo pharmacological experiments. BBS reduced the lung index, viral titer, and degree of EV71-induced lung, brain, and skeletal muscle damage. The mechanism of anti-EV71 activity of BBS was also investigated by using ELISA and qRT-PCR, and it was found that BBS exerted its action mainly by regulating the expression of TLR3, TLR4, TNF-α, IL-2, and IFN-γ by modulating the activation of NF-κB and JAK2/STAT1 signaling pathways. Finally, the chemical structures of the active monomers in BBS were determined by using UPLC-MS and NMR techniques. The study revealed that one of the monomers on which BBS exerts its antiviral activity is saponarin. In conclusion, the results of this study suggest that BBS is considered a natural anti-EV71 product with enormous potential, and saponarin would be its non-negligible active monomer.

5.
Appl Radiat Isot ; 198: 110852, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37210867

RESUMO

In this work, the independent fission cross-sections of U(n,f)238Xe135g and U(n,f)238Xe135m reactions induced by neutrons with the energies of 14.1 MeV, 14.5 MeV, and 14.7 MeV were measured by activation methods. The neutrons from T(d,n)He4 were used in the experiments and their energies were determined by the ratio of Zr(n,2n)90Zr89 and Nb(n,2n)93Nb92m reaction cross-sections. Aluminum films were chosen as reference samples to measure the neutron fluence relative to the cross section of the Al(n,α)27Na24 reaction. The effect of self-absorption, geometry, and cascade coincidence were also considered during the data analysis. Besides, the increase in the daughter nuclide yield due to the decay of the parent nuclides in the same decay chain was deducted. As a result, the independent fission cross-sections of the U(n,f)238Xe135g reaction are 2.54 ± 0.14 mb, 3.05 ± 0.19 mb and 2.94 ± 0.19 mb, while the cross-sections of U(n,f)238Xe135m reaction are 2.11 ± 0.16 mb, 2.47 ± 0.18 mb and 2.34 ± 0.21 mb for 14.1 MeV, 14.5 MeV and 14.7 MeV neutrons, respectively. This work provides experimental data for the database of nuclear fission reactions.


Assuntos
Nêutrons , Radioisótopos , Alumínio
6.
Front Genet ; 14: 1041103, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923796

RESUMO

Grasscutter (Thryonomys swinderianus) is a large-body old world rodent found in sub-Saharan Africa. The body size and the unique taste of the meat of this major crop pest have made it a target of intense hunting and a potential consideration as a micro-livestock. However, there is insufficient knowledge on the genetic diversity of its populations across African Guinean forests. Herein, we investigated the genetic diversity, population structures and evolutionary history of seven Nigerian wild grasscutter populations together with individuals from Cameroon, Republic of Benin, and Ghana, using five mitochondrial fragments, including D-loop and cytochrome b (CYTB). D-loop haplotype diversity ranged from 0.571 (± 0.149) in Republic of Benin to 0.921 (± 0.013) in Ghana. Within Nigeria, the haplotype diversity ranged from 0.659 (± 0.059) in Cross River to 0.837 (± 0.075) in Ondo subpopulation. The fixation index (FST), haplotype frequency distribution and analysis of molecular variance revealed varying levels of population structures across populations. No significant signature of population contraction was detected in the grasscutter populations. Evolutionary analyses of CYTB suggests that South African population might have diverged from other populations about 6.1 (2.6-10.18, 95% CI) MYA. Taken together, this study reveals the population status and evolutionary history of grasscutter populations in the region.

7.
Chin Herb Med ; 14(2): 310-316, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36117666

RESUMO

Objective: The current investigation aimed to determine the appropriate dosage form by comparing solid dispersion and liposome to achieve the purpose of improving the solubility and bioavailability of linarin. Methods: Linarin solid dispersion (LSD) and linarin liposome (LL) were developed via the solvent method and the thin film hydration method respectively. The Transwell chamber model of Caco-2 cells was established to evaluate the absorption of drug. The pharmacokinetics of linarin, LSD and LL in rats after ig administration were carried out by high performance liquid chromatography (HPLC) method. Results: The solubility of LSD and LL was severally 3.29 times and 3.09 times than that of linarin. The permeation coefficients of LSD and LL were greater than 10-6, indicating that the absorption of LSD and LL were both better than linarin. The bioavailability of the LSD was 3.363 times higher than that of linarin, and the bioavailability of LL was 0.9886 times higher than that of linarin. Conclusion: The linarin was more suitable for making solid dispersion to enhance its solubility and bioavailability.

8.
Micron ; 157: 103263, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35390752

RESUMO

Precision elemental analysis by EELS at a nano-meter scale is a desirable goal for industrial application, as well as basic scientific research on advanced material analysis. However, sample thickness variation leads to a systematic error in element quantification due to electron plural scattering events and prevents it to be a useful quantitative analytic method. In this paper, we compared three methods to minimize thickness effect: Fourier-log deconvolution, Jump ratio, and Si K-edge by quantifying the N/Si ratio versus different thickness on a standard Si3N4 crystal sample. The results indicated that Jump ratio method exceeded other two methods owing to its higher accuracy, short data acquisition time as well as minimum requirement for spectroscopy instrument. The jump ratio method was applied to calculate N/Si ratio in storage nitride layer of 3D NAND trench wafer and blanket wafer, both illustrated that the jump ratio method successfully corrected the thickness effect on EELS composition quantification and largely reduced the relative error compared with the non-corrected result.

9.
Molecules ; 28(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36615326

RESUMO

Matricaria chamomilla L. (MC) and Chamaemelum nobile (L.) All. (CN) are two varieties of Chamomile. These herbs have been used for thousands of years in Greece, Rome and ancient Egypt. Chamomile has been used for the treatment of stomach problems, cramps, dermatitis, and minor infections. The purpose of this study was to introduce the botanical characteristics and geographical distribution, traditional uses, chemical constituents, pharmacological activities, toxicity studies and quality control studies, and lay a theoretical foundation for the rational development and utilization of chamomile. This review powered that chemical constituents include flavonoids, coumarins, volatile oils, terpenes, organic acids, polysaccharides, and others. These compounds possess anticancer, anti-infective, anti-inflammatory, antithrombotic, antioxidant, hypolipidaemic, hypoglycaemic, antihypertensive, antidepressant, neuroprotective activities, among others. Chamomile is a widely used herb in traditional medicine. It brings great economic value due to its numerous pharmacological effects and traditional uses. However, more toxicity tests should be carried out to confirm its safety. There is need for further research to provide concrete scientific evidence and validate its medicinal properties.


Assuntos
Camomila , Óleos Voláteis , Extratos Vegetais/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Terpenos , Controle de Qualidade , Medicina Tradicional
10.
Mitochondrial DNA B Resour ; 6(7): 2092-2094, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34212107

RESUMO

Thrips hawaiiensis (Morgan) (Thysanoptera: Thripidae) is a common Thysanoptera insect widely distributed in Asia and the Pacific, it damages various plants. In this study the complete mitochondrial genome of T. hawaiiensis was sequenced and characterized by using next-generation sequencing technique. The total length of the complete genome is 15,357 bp and A + T content of 77.8% (GeneBank accession No. MW582621). The T. hawaiiensis mitochondrial genome consists of 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA genes (tRNAs) and 2 non-coding control regions (Dloop region). According to previous studies, only a few complete mitochondrial genomes from Order Thysanoptera have been reported. Thus, T. hawaiiensis complete mitochondrial genome sequence reported will provide molecular information for mitochondrial genome research on Thysanoptera.

11.
Biomed Pharmacother ; 141: 111843, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34175821

RESUMO

OBJECTIVE: To investigate the antiviral effect of Salvia plebeia R. Br. polysaccharides (SPP) against RSV and underlying mechanisms. METHODS: SPP was extracted via alcohol-precipitation method and extract was separated into various fractions using ultrafiltration method. The polysaccharide content was determined using UV-Vis. Antiviral effect of SPP and fractions was measured using MTT method and Reed-Muench method. Sixty Balb/c mice were randomly divided into 6 groups, and received either Ribavirin or SPP. Their body weight and food intake were recorded every day throughout the experiment period. The lung index inhibition ratio and pulmonary virus titer were determined followed by the histological analysis of lungs. Furthermore, time-of-addition and effective stage analysis were carried out to determine the mechanism of action. The TLR-3 and TLR-4 levels in the lungs were determined using qRT-PCR. The levels of IFN-γ, IL-2 and TNF-α in serum were determined using ELISA. RESULTS: The SPP content is 4.396%. SPP has shown a good anti-RSV effect both in vitro (TI = 123.041) and in vivo models. The antiviral activity of fractions with molecular weight ≥ 10,000 is found to possess more potent antiviral activity than other fractions. SPP inhibits the RSV proliferation and reduces the lung lesions induced by RSV. The mechanism of action involves the inhibition of TLR-3 and TLR-4 in lungs, up-regulation of IFN-γ and IL-2, and down-regulation of TNF-α in serum. It is also shown to improve the body's immune function. CONCLUSION: SPP has a potential to treat diseases caused by RSV.


Assuntos
Antivirais/farmacologia , Antivirais/uso terapêutico , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Salvia/química , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Citocinas/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais , Testes de Função Respiratória , Ribavirina/uso terapêutico , Sais de Tetrazólio , Tiazóis , Receptores Toll-Like/metabolismo
12.
Micron ; 146: 103065, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33940344

RESUMO

In EELS core loss excitation, inverse jump ratio is defined as a ratio between intensity of a pre-core-loss-edge and a signal of the core loss excitation after background subtraction. A linear relationship between inverse jump ratio of Si L-edge and O/Si and N/Si intensity ratio is found for electron energy loss spectroscopy (EELS) analysis. This relationship is used to analyze O/Si and N/Si atomic ratio to quantify the elemental distribution in SiON films and the result is compared with XPS analysis on the same SiON films. The method is applied to blanket wafer elemental analysis and can be used for flash memory structure (3D NAND) to obtain atomic ratios of N/Si and O/Si for tunnel oxide at sub-nanometer scale.

13.
Small ; 17(19): e2100098, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33788402

RESUMO

The nitride films with high indium (In) composition play a crucial role in the fabrication of In-rich InGaN-based optoelectronic devices. However, a major limitation is In incorporation requiring a low temperature during growth at the expense of nitride dissociation. Here, to overcome this limitation, a strain-modulated growth method, namely the graphene (Gr)-nanorod (NR) enhanced quasi-van der Waals epitaxy, is proposed to increase the In composition in InGaN alloy. The lattice transparency of Gr enables constraint of in-plane orientation of nitride film and epitaxial relationships at the heterointerface. The Gr interlayer together with NRs buffer layer substantially reduces the stress of the GaN film by 74.4%, from 0.9 to 0.23 GPa, and thus increases the In incorporation by 30.7%. The first principles calculations confirm that the release of strain accounts for the dramatic improvement. The photoluminescence peak of multiple quantum wells shifts from 461 to 497 nm and the functionally small-sized cyan light-emitting diodes of 7 × 9 mil2 are demonstrated. These findings provide an efficient approach for the growth of In-rich InGaN film and extend the applications of nitrides in advanced optoelectronic, photovoltaic, and thermoelectric devices.

14.
Ultramicroscopy ; 220: 113164, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33186852

RESUMO

An energy band gap measurement method based on nano-beam STEM with small off-axis angle valence band transmission electron energy loss spectroscopy (TEELS) is reported. The effect of multiple scattering event is removed by self-convolution method to obtain a single scattering loss function and a dielectric function is calculated from the single scattering valence band energy loss function through Kramers-Kronig (K-K) analysis. Optical band gaps are extracted from energy loss spectra and the imaginary part of the dielectric functions for crystalline and amorphous SiOx, SiNx, and SiON through linear fitting of on-set regions yielding results that are independent of sample thickness. The TEELS band gap data are consistent with those obtained from reflection electron energy loss spectroscopy (REELS) measurements.

15.
Mol Biol Rep ; 47(12): 9441-9457, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33200313

RESUMO

Accurate identification of species is a prerequisite for successful biodiversity management and further genetic studies. Species identification techniques often require both morphological diagnostics and molecular tools, such as DNA barcoding, for correct identification. In particular, the use of the subunit I of the mitochondrial cytochrome c oxidase (COI) gene for DNA barcoding has proven useful in species identification for insects. However, to date, no studies have been carried out on the DNA barcoding of Nigerian butterflies. We evaluated the utility of DNA barcoding applied for the first time to 735 butterfly specimens from southern Nigeria. In total, 699 DNA barcodes, resulting in a record of 116 species belonging to 57 genera, were generated. Our study sample comprised 807 DNA barcodes based on sequences generated from our current study and 108 others retrieved from BOLD. Different molecular analyses, including genetic distance-based evaluation (Neighbor-Joining, Maximum Likelihood and Bayesian trees) and species delimitation tests (TaxonDNA, Automated Barcode Gap Discovery, General Mixed Yule-Coalescent, and Bayesian Poisson Tree Processes) were performed to accurately identify and delineate species. The genetic distance-based analyses resulted in 163 well-separated clusters consisting of 147 described and 16 unidentified species. Our findings indicate that about 90.20% of the butterfly species were explicitly discriminated using DNA barcodes. Also, our field collections reported the first country records of ten butterfly species-Acraea serena, Amauris cf. dannfelti, Aterica galena extensa, Axione tjoane rubescens, Charaxes galleyanus, Papilio lormieri lormeri, Pentila alba, Precis actia, Precis tugela, and Tagiades flesus. Further, DNA barcodes revealed a high mitochondrial intraspecific divergence of more than 3% in Bicyclus vulgaris vulgaris and Colotis evagore. Furthermore, our result revealed an overall high haplotype (gene) diversity (0.9764), suggesting that DNA barcoding can provide information at a population level for Nigerian butterflies. The present study confirms the efficiency of DNA barcoding for identifying butterflies from Nigeria. To gain a better understanding of regional variation in DNA barcodes of this biogeographically complex area, future work should expand the DNA barcode reference library to include all butterfly species from Nigeria as well as surrounding countries. Also, further studies, involving relevant genetic and eco-morphological datasets, are required to understand processes governing mitochondrial intraspecific divergences reported in some species complexes.


Assuntos
Sequência de Bases/genética , Borboletas/enzimologia , Borboletas/genética , Código de Barras de DNA Taxonômico/métodos , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Mitocondriais , Animais , Teorema de Bayes , Biodiversidade , DNA Mitocondrial/isolamento & purificação , Variação Genética , Haplótipos , Nigéria , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
16.
Insects ; 11(6)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599938

RESUMO

Losaria coon (Fabricius, 1793) is currently comprised of ten subspecies, which were originally described under two names, Papilio coon and P. doubledayi before 1909, when they were combined as one species. The main difference between them is the colour of abdomen and hindwing subterminal spots-yellow in coon and red in doubledayi. Wing morphology, male and female genitalia, and molecular evidence (DNA barcodes) were analysed for multiple subspecies of L. coon and three other Losaria species-rhodifer, neptunus, and palu. Our molecular data support the separation of L. coon and L. doubledayi stat. rev. as two distinct species, with L. rhodifer positioned between them in phylogenetic analyses. Wing morphology and genitalic structures also confirm the molecular conclusions. Our findings divide L. coon into two species occupying different geographic ranges: with L. coon restricted to southern Sumatra, Java, and Bawean Island, while L. doubledayi occurs widely in regions from North India to northern Sumatra, including Hainan and Nicobar Islands. Hence, future conservation efforts must reassess the status and threat factors of the two species to form updated strategies.

17.
Sci Rep ; 10(1): 7097, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341417

RESUMO

The silver butter catfish (Schilbe intermedius) is widely distributed across African river systems. To date, information on its mitochondrial genetic diversity, population structure, and historical demography are not well-established. Herein, we combined newly generated mitochondrial cytochrome c oxidase (COI) subunit I gene sequences with previously published COI sequences in the global databases to reconstruct its phylogeography, population genetic structure, and historical demography. Results from the mtDNA phylogeography and species delimitation tests (Cluster algorithm - Species Identifier, Automatic Barcode Gap Discovery and Poison Tree Process model) revealed that S. intermedius comprises at least seven geographically defined matrilines. Although the overall haplotype diversity of S. intermedius was high (h = 0.90), results showed that East (Kenya) and West (Nigeria) African populations had low levels of haplotype diversity (h = ~0.40). In addition, population genetic polymorphism and historical demographics showed that S. intermedius populations in both East and West Africa underwent severe contractions as a result of biogeographic influences. The patterns of genetic diversity and population structure were consistent with adaptive responses to historical biogeographic factors and contemporary environmental variations across African river systems. This is suggestive of the influence of historical biogeographic factors and climatic conditions on population divergence of S. intermedius across African river systems. Given our discovery of previously underappreciated diversity within S. intermedius, we recommend that this species be considered for increased conservation and management.


Assuntos
Peixes-Gato/genética , Código de Barras de DNA Taxonômico , DNA Mitocondrial/genética , Variação Genética , Filogenia , Animais , Quênia , Nigéria , Filogeografia , Rios
19.
Chin Herb Med ; 12(3): 336-341, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36119007

RESUMO

Objective: To make full usage of resource and turn waste into treasure, the chemical constituents and bioactivity were firstly investigated on Damask rose (Rosa damascena) flower residue (DRFR). Methods: DPPH and ABTS experiments were applied to assess the antioxidant activity of DRFR. Then, column chromatography was used to purify compounds from an antioxidation extract (DRFR-A), and the chemical structure was identified using NMR. The total phenolic acid content was measured by Folin-Ciocalteu colorimetric method, and the content of gallic acid of the indicator ingredient was detected by HPLC. Results: DRFR-A was found to show a high activity both on DPPH (IC50: 2.760 µg/mL) and ABTS (IC50: 2.258 µg/mL) compared to positive control VC. Ten compounds were isolated and identified as quercetin (1), kaempferol (2), gallic acid (3), protocatechuic acid (4), pyrogallic acid (5), 2-phenylethyl 3,4,5-trihydroxybenzoate (6), methyl gallate (7), p-hydroxybenzoic acid (8), p-hydroxyphenethyl alcohol (9) and astragalin (10) from DRFR-A. Among them, pyrogallic acid, 2-phenylethyl-3, 4, 5-trihydroxybenzoate, p-hydroxybenzoic acid and p-hydroxyphenethyl alcohol are obtained from the plant for the first time. The content of total phenolic acids and gallic acid, main ingredient in DRFR-A was determined as 63.73% and 24.67%, respectively. Conclusion: This study provides a reliable data and lays the foundation for the development and utilization of rose residue, and hence for the full utilization of rose resources.

20.
Se Pu ; 37(10): 1048-1052, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642282

RESUMO

A method for the rapid screening of 1,3-dichloro-2-propanol, 2,3-dichloro-1-propanol,3-monochloropropane-1,2-diol, and 2-monochloropropane-1,3-diol in soy sauce was developed based on dispersive solid phase extraction-gas chromatography-high resolution mass spectrometry (GC-HRMS). The samples were extracted by ethyl acetate, cleaned up using N-propylethylenediamine and detected by GC-HRMS. The chloropropanols were quantified by the internal standard method. The results demonstrated that the limits of quantitation of the four chloropropanols were in the range of 0.5-10 µg/kg. The recoveries of the four chloropropanols in soy sauce spiked with three levels varied from 78% to 103%, and the relative standard deviations were no more than 8.8%. The proposed method is simple, accurate, sensitive and suitable for the rapid screening of the four chloropropanols in soy sauce.


Assuntos
Propanóis/análise , Alimentos de Soja/análise , Cromatografia Gasosa-Espectrometria de Massas , Extração em Fase Sólida
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