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1.
J Biomol Struct Dyn ; : 1-11, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37674457

RESUMO

Tyrosinase is the rate-limiting enzyme in synthesizing melanin. Melanin is responsible for changing the color of fruits and vegetables and protecting against skin photo-carcinogenesis. Herein, some of the hybrids of 3-hydroxypyridine-4-one and acylhydrazones were designed and synthesized to study the anti-tyrosinase and antioxidant activities. The diphenolase activity of mushroom tyrosinase using L-DOPA assayed the inhibitory effects, and the antioxidant activity was assessed using DPPH free radical. The synthesized derivatives were confirmed using 1H-NMR, 13C-NMR, IR, and Mass spectroscopy. Among analogs, compound 5h bearing furan ring with IC50=8.94 µM was more potent than kojic acid (IC50=16.68 µM). The pharmacokinetic profile of the compounds showed that the tested compounds had suitable oral bioavailability and drug-likeness properties. The molecular docking studies showed that compound 5h was located in the tyrosinase-binding site. Also, the molecular dynamics simulation was performed on compound 5h, proving the obtained molecular docking results. At the B3LYP/6-31 + G** level of theory, the reactivity descriptors for 5 g and 5h were investigated using DFT calculations. Also, IR frequency was calculated to verify DFT results with experimental data. The electrostatic potential energy of the surface and the HOMO and LUMO molecular orbitals were also studied. It agrees with experimental results that the 5h is a soft molecule and ready for chemical reaction with other interacting molecules.Communicated by Ramaswamy H. Sarma.

2.
Pharmaceuticals (Basel) ; 15(7)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35890128

RESUMO

Phenolic compounds represent an essential bioactive metabolites group with numerous pharmaceutical applications. Our study aims to identify and quantify phenolic constituents of various liquid and dry extracts of Usnea barbata (L.) Weber ex F.H. Wigg (U. barbata) from Calimani Mountains, Romania, and investigate their bioactivities. The extracts in acetone, 96% ethanol, and water with the same dried lichen/solvent ratio (w/v) were obtained through two conventional techniques: maceration (mUBA, mUBE, and mUBW) and Soxhlet extraction (dUBA, dUBE, and dUBW). High-performance liquid chromatography with diode-array detection (HPLC-DAD) was performed for usnic acid (UA) and different polyphenols quantification. Then, the total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging activity (AA) were determined through spectrophotometric methods. Using the disc diffusion method (DDM), the antibacterial activity was evaluated against Gram-positive and Gram-negative bacteria known for their pathogenicity: Staphylococcus aureus (ATCC 25923), Streptococcus pneumoniae (ATCC 49619), Pseudomonas aeruginosa (ATCC 27853), and Klebsiella pneumoniae (ATCC 13883). All extracts contain phenolic compounds expressed as TPC values. Five lichen extracts display various UA contents; this significant metabolite was not detected in dUBW. Six polyphenols from the standards mixture were quantified only in ethanol and water extracts; mUBE has all individual polyphenols, while dUBE shows only two. Three polyphenols were detected in mUBW, but none was found in dUBW. All U. barbata extracts had antiradical activity; however, only ethanol and acetone extracts proved inhibitory activity against P. aeruginosa, S. pneumoniae, and S. aureus. In contrast, K. pneumoniae was strongly resistant (IZD = 0). Data analysis evidenced a high positive correlation between the phenolic constituents and bioactivities of each U. barbata extract. Associating these extracts' properties with both conventional techniques used for their preparation revealed the extraction conditions' significant influence on lichen extracts metabolites profiling, with a powerful impact on their pharmacological potential.

3.
J Sci Food Agric ; 102(15): 7221-7230, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35730767

RESUMO

BACKGROUND: The soy isoflavone microbial metabolites dihydrodaidzein (DHD), dihydrogenistein (DHG), equol and 5-hydroxy-equol are generally more biologically active than their precursors daidzein and genistein. Bacteria responsible for isoflavone metabolism have been isolated and identified. Fermented soymilk is a potential functional food; however, there are few lactic acid bacteria capable of metabolizing soy isoflavones. RESULTS: A newly isolated Gram-positive facultative anaerobic bacterium, which was named Lactobacillus acidipiscis HAU-FR7, was isolated from the traditional Chinese fermented soy product 'stinky tofu'. Bacterium strain HAU-FR7 can grow under aerobic conditions and can also convert most of the daidzin and genistin in soymilk into DHD and DHG, respectively. The concentrations of DHD and DHG produced were 183 and 134 µmol L-1 , respectively, after fermentation for 24 h. Strain HAU-FR7 does not produce the biogenic amines cadaverine, putrescine, histamine or tyramine, and an antibiotic susceptibility test showed that HAU-FR7 is sensitive to nine of the ten tested antibiotics, except for vancomycin. Moreover, the 1,1-diphenyl-2- picrylhydrazyl free radical scavenging capacity of soymilk fermented with HAU-FR7 was significantly higher than that of unfermented soymilk. CONCLUSION: A facultative anaerobic lactic acid bacterium, designated Lactobacillus acidipiscis HAU-FR7, is capable of reducing the soy isoflavone glucosides daidzin and genistin in soymilk to DHD and DHG efficiently, even in the presence of atmospheric oxygen. The biotransformation activity of HAU-FR7 grown in soymilk is higher than that in de Man-Rogosa-Sharpe liquid culture medium. © 2022 Society of Chemical Industry.


Assuntos
Isoflavonas , Alimentos de Soja , Leite de Soja , Humanos , Fermentação , Glucosídeos/metabolismo , Composição de Bases , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Leite de Soja/metabolismo , Isoflavonas/metabolismo , Bactérias/metabolismo , China
4.
Acta Pharmaceutica Sinica ; (12): 2120-2125, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-936566

RESUMO

To study the chemical constituents from the the deep-sea fungus Alternaria sp. F49. Seven compounds were isolated from the EtOAc extract by using silica gel, Sephadex LH-20, ODS and HPLC methods. Based on the spectroscopic analysis, their structures were identified as (8R)-5-O-methyl-orcinotriol (1), orcinotriol (2), α-acetylorcinol (3), 3'-hydroxyalternariol 5-O-methyl ether (4), altenusiol (5), altenusin (6), and 5'-methoxy-6-methyl-biphenyl-3,4,3'-triol (7). (8R)-5-O-Methyl-orcinotriol (1) is a new phenolic compound which has never been reported in the literature. Compounds 4-7 showed strong DPPH free radical scavenging activity; whereas compounds 1-7 showed strong ABTS free radical scavenging activity.

5.
Food Sci Nutr ; 9(2): 1192-1201, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33598203

RESUMO

Wheat germ is produced as a by-product during wheat milling operations and is a relatively inexpensive protein source that, in spite of its exclusive nutritional properties, is mostly used for animal feed formulation and has limited use in the food industry. In this study, wheat germ extract (WGE) was microencapsulated by spray and freeze drying and with different ratios of maltodextrin to whey protein concentrate (M-W) as the coating material and then physicochemical properties of the microcapsules were evaluated. Results showed decreased moisture content and increased solubility, lipase activity, acid phosphatase activity, and both lipase and acid phosphatase microencapsulation efficiency with increasing M-W ratios in both drying methods. The M-W ratios had no significant effects on the DPPH free radical scavenging activity in both methods. With increasing M-W ratios, particle size decreased and bulk density increased in the spray drying method, while particle size increased and bulk density decreased in the freeze drying method. Spray drying elevated solubility, DPPH free radical scavenging activity, lipase activity, acid phosphatase activity, and both lipase and acid phosphatase microencapsulation efficiency, in comparison with the freeze drying method.

6.
Mater Sci Eng C Mater Biol Appl ; 116: 111184, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806262

RESUMO

Current report is paramount contribution via nanotechnology to the existing remedies of health diseases. The lag in application of capped metallic oxide nanoparticles in restorative dentistry exist which is covered by this promising study. The uncapped and chitosan encapsulated ZnO nanoparticles were fabricated by facile co-precipitation method, and characterized using various biophysical strategies including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Energy dispersive x-ray (EDX). ZnO nanoparticles and ZnO-Citosan nanoparticles were estimated to be <30 nm and <25 nm in size on respective basis. Significant in vitro antibacterial, antioxidant, cytotoxic and antidiabetic activity of ZnO nanoparticles has been elucidated that is enhanced by capping with chitosan polymer. 90% cytotoxicity against brine shrimps, 69.6% antidiabetic activity against α-amylase, and noteworthy antioxidation power by chitosan decorated ZnO nanoparticles has been effectively illustrated. Furthermore, the effective secondary caries remediation approach has been established by an amalgamation of ZnO nanoparticles and ZnO-Chitosan nanoparticles into dentine bonding agents. A remarkable reduction in Streptococcus mutans and Lactobacillus acidophillus strains has been observed, in-specific boosted by chitosan capped ZnO nanoparticles reinforced dental adhesive discs. Additionally, augmented mechanical properties, greater resistance to water sorption and solubility, notably high release profile, and slight variation of shear bond strength values have been obtained. In short, the prepared nanoparticles reported are detected to be auspicious theranostic agents for combating wide array of human pathogens in healthcare system.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanocompostos , Nanopartículas , Óxido de Zinco , Animais , Antibacterianos/farmacologia , Humanos , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
J Mol Struct ; 1214: 128252, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32292211

RESUMO

A group of new nitro substituted benzoxazinones (3a-k) were synthesized from easily available 4-nitroanthranilic acid. All the synthesized compounds were characterized by FT-IR, 1H NMR, 13C NMR, mass spectrometry and elemental analysis. Anti-proliferative and pro-apoptotic potential of all the synthesized compounds (3a-k) was evaluated by MTT and Hoechst 33258 staining assay respectively whereas their antioxidant properties were determined via DPPH free radical scavenging assay. The most active compounds (3a, 3c and 3k) showed significant cytotoxic potential against HeLa cells with an inhibition of cell viability that ranged between 28.54 and 44.67% (P < 0.001). Albeit statistically different, the anti-proliferative effect of 3c was in close match with that of the reference drug doxorubicin. Likewise, the test compounds showed profound pro-apoptotic potential with an apoptotic index that ranged between 52.86 and 75.61%. Besides, the docking studies revealed a higher efficiency for compounds (3a and 3h) owing to their better affinity and inhibition constant (Ki = 4.397 and 3.713 nmol) respectively. The antioxidant potential of synthesized benzoxazinones (3a-k) was in close agreement with the experimental anticancer results with a percent inhibition from 34.45 to 85.93% as compared to standard (90.56%).

8.
Zhongguo Zhong Yao Za Zhi ; 44(14): 3042-3048, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31602851

RESUMO

To establish the spectrum-effect relationship between HPLC fingerprint and free radicals activity scavenging in Guizhi Shaoyao Zhimu Decoction( GSZD),and provide a basis for the quality evaluation and modernization of classical prescriptions. Shimadsu GL-science C18 column( 4. 6 mm×250 mm,5 µm) was used with acetonitrile-0. 1% formic acid solution as the mobile phase for gradient elution. The detective wave length was 254 nm; the column temperature was set at 32 ℃; the injection volume was 20 µL; and the flow rate was 1. 0 m L·min-1.10 batches of primary standard samples of GSZD were detected,and their HPLC fingerprint was established by using the similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine( TCM). The activity of scavenging free radicals was studied by 1,1-diphenyl-2-trinitrophenylhydrazine( DPPH) method,and the spectrum-effect relationship was studied by Pearson bivariate correlation analysis. The common mode of GSZD fingerprints was established,and 26 common peaks were marked,with similarities ranging from 0. 929 to 0. 998. Eight of the chromatographic peaks were identified by using the control comparison method: gallic acid,mangiferin,paeoniflorin,glycyrrhizin,asparagus,5-O-methylvisamicin,cinnamic acid,and ammonium glycyrrhetate. Among them,the content changes of No. 14( paeoniside),20,12( mangiferin),13 and 23( cinnamic acid) common peaks were negatively correlated with free radical scavenging activity. The fingerprint showed high precision,repeatability and stability,and the common peaks were well separated,so it can be used for the quality evaluation of GSZD,and could provide reference for further studies on the material basis of GSZD.


Assuntos
Cinnamomum aromaticum/química , Medicamentos de Ervas Chinesas/química , Sequestradores de Radicais Livres/química , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa
9.
Molecules ; 24(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108854

RESUMO

In the present study, the composition of essential oil isolated from the roots of Vetiveria zizanioides (L.) Nash, harvested in China, was studied, along with the bioactivities. A green novel method using an eco-friendly solvent, CO2-pressurized ethanol, or carbon dioxide expanded ethanol (CXE) was employed to isolate the essential oil from the root of Vetiveria zizanioides (L.) Nash with the purpose of replacing the traditional method and supercritical fluid extraction (SFE). After investigating the major operating factors of CXE, the optimal conditions were obtained as follows: 8.4 MPa, 50 °C, 5 mL/min ethanol, and 0.22 mole fraction of CO2, presenting an extraction oil that ranged from 5.12% to 7.42%, higher than that of hydrodistillation (HD) or indirect vapor distillation (IVD). The Gas Chromatography-Mass Spectrometry (GC-MS) analysis showed that three major components, including valerenol (18.48%), valerenal (10.21%), and ß-Cadinene (6.23%), are found in CXE oil, while a total of 23 components were identified, 48 components less than using conventional hydrodistillation. Furthermore, the antimicrobial activities of root oils were evaluated by the microdilution method, which showed that CXE oil exhibited an ability against Gram-positive bacteria, especially Staphylococcus aureus, approximately equivalent to traditional samples. Additionally, the DPPH free radical scavenging assay demonstrated that the antioxidant abilities of root oils were sorted in the descending order: IVD > HD > CXE > SFE. In conclusion, after a comprehensive comparison with the conventional methods, the CXE-related technique might be a promising green manufacturing pattern for the production of quality vetiver oil, due to the modification of ethanol by the variable addition of non-polar compressible CO2, ultimately resulting in a prominent dissolving capability for the extraction of vetiver solutes.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Vetiveria/química , Óleos Voláteis/farmacologia , Anti-Infecciosos/química , Antioxidantes/química , Bactérias/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia
10.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-766386

RESUMO

This study examined the quality characteristics of brown rice Sulgidduk containing acorn powder and the optimal mixing rate (0%, 5%, 10%, and 15%). The moisture contents of brown rice Sulgidduk increased with increasing amount of acorn powder. The DPPH free radical scavenging activities (16.15%~28.06%) and ABTS free radical scavenging activities (22.98%~42.81%) of the brown rice Sulgidduk increased with increasing acorn powder content. The L value of the Hunter's color value decreased with increasing amount of acorn powder. The hardness and chewiness of brown rice Sulgidduk increased with increasing amount of acorn powder. The brown rice Sulgidduk containing 10% acorn powder showed the highest score with regard to the sensory characteristics. These results suggest that the most desirable amount of acorn powder is 10% and the addition of acorn powder could contribute positively toward the quality characteristics of brown rice Sulgidduk.


Assuntos
Dureza
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-773192

RESUMO

To establish the spectrum-effect relationship between HPLC fingerprint and free radicals activity scavenging in Guizhi Shaoyao Zhimu Decoction( GSZD),and provide a basis for the quality evaluation and modernization of classical prescriptions. Shimadsu GL-science C18 column( 4. 6 mm×250 mm,5 μm) was used with acetonitrile-0. 1% formic acid solution as the mobile phase for gradient elution. The detective wave length was 254 nm; the column temperature was set at 32 ℃; the injection volume was 20 μL; and the flow rate was 1. 0 m L·min-1.10 batches of primary standard samples of GSZD were detected,and their HPLC fingerprint was established by using the similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine( TCM). The activity of scavenging free radicals was studied by 1,1-diphenyl-2-trinitrophenylhydrazine( DPPH) method,and the spectrum-effect relationship was studied by Pearson bivariate correlation analysis. The common mode of GSZD fingerprints was established,and 26 common peaks were marked,with similarities ranging from 0. 929 to 0. 998. Eight of the chromatographic peaks were identified by using the control comparison method: gallic acid,mangiferin,paeoniflorin,glycyrrhizin,asparagus,5-O-methylvisamicin,cinnamic acid,and ammonium glycyrrhetate. Among them,the content changes of No. 14( paeoniside),20,12( mangiferin),13 and 23( cinnamic acid) common peaks were negatively correlated with free radical scavenging activity. The fingerprint showed high precision,repeatability and stability,and the common peaks were well separated,so it can be used for the quality evaluation of GSZD,and could provide reference for further studies on the material basis of GSZD.


Assuntos
Cromatografia Líquida de Alta Pressão , Cinnamomum aromaticum , Química , Medicamentos de Ervas Chinesas , Química , Sequestradores de Radicais Livres , Química , Medicina Tradicional Chinesa
12.
Environ Sci Pollut Res Int ; 25(11): 10250-10263, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28303540

RESUMO

Process byproducts from the fruit industry may represent a cheap and reliable source of green reducing agents to be used in current bio-nanosynthesis. This study reports the use of orange (Citrus × clementina) peel aqueous extract (OPE) for one-pot green synthesis of silver nanoparticles (AgNPs) with high effectiveness against various microbial pathogens as well as rat glial tumor C6 cells. The effects of various operational parameters on the synthesis of AgNPs were systematically investigated. The morphology, particle size, and properties of synthesized AgNPs were characterized using UV-visible spectroscopy, x-ray diffraction, x-ray photoelectron spectroscopy, field emission scanning electron microscopy, energy-dispersive x-ray spectroscopy, and Fourier transform infrared spectroscopy. High-resolution transmission electron microscopy shows that the nanoparticles are mostly spherical in shape and monodispersed, with an average particle size of 15-20 nm. Notably, the OPE-synthesized AgNPs were stable up to 6 months without change in their properties. Low doses of OPE-AgNPs inhibited the growth of human pathogens Escherichia coli, Bacillus cereus, and Staphylococcus aureus. The minimum inhibitory concentration and minimum bactericidal concentration of AgNPs against selected pathogenic bacteria were determined. OPE-AgNPs exhibited strong antioxidant activity in terms of ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) radical scavenging (IC50 49.6 µg/mL) and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging (IC50 63.4 µg/mL). OPE-AgNPs showed dose-dependent response against rat glial tumor C6 cells (LD50 60 µg/mL) showing a promising potential as anticancer agents. Overall, the current investigation highlighted a cheap green technology route to synthesize AgNPs using OPE byproducts and could potentially be utilized in biomedical, cosmetic, and pharmaceutical industry.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Compostos de Bifenilo/química , Citrus/química , Frutas/química , Nanopartículas Metálicas/química , Picratos/química , Extratos Vegetais/farmacologia , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/química , Antineoplásicos/química , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Ratos , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
13.
Fitoterapia ; 111: 12-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27072985

RESUMO

Giganteone E (1), a new dimeric acylphenol was isolated as a minor constituent from the bark of Myristica maxima Warb. The structure of 1 was established on the basis of 1D and 2D NMR techniques and LCMS-IT-TOF analysis. Malabaricones A-C (2-4), giganteones A and C (5 and 6), maingayones A and B (7 and 8), maingayic acid B (9) and ß-sitosteryl oleate (10) were also characterized in this plant for the first time. Compound 10 was identified for the first time in the Myristicaceae. Compounds 2 and 5 were active against human prostate cancer cell-lines, thus making this the first report on the prostate cancer inhibiting potential of acylphenols and dimeric acylphenols. Compounds 1, 4, 5, 7 and 8 exhibited potent DPPH free radical scavenging activity. This is the first report on their free radical scavenging capacity.


Assuntos
Myristicaceae/química , Fenóis/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Humanos , Masculino , Estrutura Molecular , Fenóis/isolamento & purificação , Neoplasias da Próstata/patologia , Resorcinóis/isolamento & purificação , Resorcinóis/farmacologia
14.
Saudi J Biol Sci ; 23(3): 389-96, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27081365

RESUMO

In the present work, the response surface methodology (RSM) based on a central composite rotatable design (CCRD), was used to determine optimum conditions for the extraction of antioxidant compounds from Origanum vulgare leaves. Four process variables were evaluated at three levels (31 experimental designs): methanol (70%, 80%, and 90%), the solute:solvent ratio (1:5, 1:12.5, 1:20), the extraction time (4, 10, 16 h), and the solute particle size (20, 65, 110 micron). Using RSM, a quadratic polynomial equation was obtained by multiple regression analysis for predicting optimization of the extraction protocol. Analysis of variance (ANOVA) was applied and the significant effect of the factors and their interactions were tested at 95% confidence interval. The antioxidant extract (AE) yield was significantly influenced by solvent composition, solute to solvent ratio, and time. The maximum AE was obtained at methanol (70%), liquid solid ratio (20), time (16 h), and particle size (20 micron). Predicted values thus obtained were closer to the experimental value indicating suitability of the model. Run 25 (methanol:water 70:30; solute:solvent 1:20; extraction time 16 h and solute particle size 20) showed highest TP contents (18.75 mg/g of dry material, measured as gallic acid equivalents) and DPPH radical scavenging activity (IC50 5.04 µg/mL). Results of the present study indicated good correlation between TP contents and DPPH radical scavenging activity. Results of the study indicated that phenolic compounds are powerful scavengers of free radical as demonstrated by a good correlation between TP contents and DPPH radical scavenging activity.

15.
Food Chem ; 194: 705-11, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26471610

RESUMO

A new computational approach for the determination of 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (DPPH-RSA) in food is reported, based on the concept of machine learning. Trolox standard was mix with DPPH at different concentrations to produce different colors from purple to yellow. Artificial neural network (ANN) was trained on a typical set of images of the DPPH radical reacting with different levels of Trolox. This allowed the neural network to classify future images of any sample into the correct class of RSA level. The ANN was then able to determine the DPPH-RSA of cinnamon, clove, mung bean, red bean, red rice, brown rice, black rice and tea extract and the results were compared with data obtained using a spectrophotometer. The application of ANN correlated well to the spectrophotometric classical procedure and thus do not require the use of spectrophotometer, and it could be used to obtain semi-quantitative results of DPPH-RSA.


Assuntos
Compostos de Bifenilo/química , Sequestradores de Radicais Livres/química , Redes Neurais de Computação , Picratos/química
16.
China Pharmacy ; (12): 2622-2625, 2016.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-501077

RESUMO

OBJECTIVE:To screen antioxidant active components of Schisandra chinensis. METHODS:The orthogonal test was adopted to optimize extraction technology using DPPH free radical scavenging activity(IC50)as index and ethanol volume frac-tion,material-liquid ratio and extraction time as factors,and the verification test were made. The fractions(SC-0,SC-10,SC-30, SC-50,SC-70,SC-95) were made by extracting and purifying S. chinensis with macroporous resin with water and 10%,30%, 50%,70%and 95%ethanol. With IC50 and total antioxidant capacity(determined by ABTS method)as indexes(vitamin C as pos-itive control),the antioxidant active components of S. chinensis were optimized. The contents of 5 kinds of lignan in different posi-tions of S. chinensis were determined by HPLC. RESULTS:The optimal extraction condition of S. chinensis was as follows as 60% ethanol,material-liquid ratio of 1∶14,extracting for 2.0 h. The average IC50 of DPPH free radical scavenging activity was 23.81 mg/ml(RSD=0.52%,n=3)in verification test. SC-0 did not have antioxidant abilities. DPPH free radical scavenging activi-ty of those components (ie. the IC50 value from low to high) were in the following order of positive control>SC-50>SC-30>SC-95>SC-70>SC-10;total antioxidant ability of them were in the following order of SC-50>positive control>SC-30>SC-70>SC-95>SC-10;the contents of 5 types of lignan in different components were in the following order of SC-70>SC-50>SC-95>SC-30. CONCLUSIONS:The antioxidant active component of S. chinensis is 50%ethanol eluate.

17.
Phytochemistry ; 103: 129-136, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24746259

RESUMO

Seven acylated flavonol glycosides named elaeagnosides A-G, in addition to seven known flavonoids were isolated from the flowers of Elaeagnus angustifolia. Their structures were elucidated by different spectroscopic methods including 1D, 2D NMR experiments and HR-ESI-MS analysis. In order to identify natural antioxidant and tyrosinase inhibitor agents, the abilities of these flavonoids to scavenge the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and to inhibit tyrosinase activity were evaluated. Results revealed that two of these compounds had significant anti-oxidant effect and one compound showed weak tyrosinase-inhibitory activity compared with kojic acid, quercetin, or ascorbic acid, which were used as positive control.


Assuntos
Elaeagnaceae/química , Flavonóis/química , Flores/química , Glicosídeos/química , Acilação , Antioxidantes/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores
18.
Asian Pac J Trop Biomed ; 3(10): 798-805, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24075345

RESUMO

OBJECTIVE: To investigate the inflammatory and antioxidant activities of ethanolic extract of aerial part of Vernonia patula (Dryand.) Merr (EAV). METHODS: The anti-inflammatory activity of EAV was studied using carrageenan and histamine-induced rat paw edema test at different doses (100, 200 and 400 mg/kg body weight). DPPH free radical scavenging, nitric oxide scavenging, reducing power and Fe(2+) ion chelating ability were used for determining antioxidant activities. RESULTS: The EAV, at the dose of 400 mg/kg, showed a significant anti-inflammatory activity (P<0.01) both in the carrageenan and histamine-induced oedema test models in rats, showing 62.86% and 64.42% reduction in the paw volume comparable to that produced by the standard drug indomethacin (67.26% and 66.01%) at 5 h respectively. In DPPH free radical scavenging test, IC50 value for EAV was found fairly significant 36.59 µg/mL when compared to the IC50 value of the reference standards ascorbic acid 8.97 µg/mL. The IC50 values of the extract and ascorbic acid were 47.72 and 12.39 µg/mL, respectively in nitric oxide scavenging assay. The IC50 value of the EAV (33.59 µg/mL) as percentage of Fe(2+) ion chelating ability was also found significant compared to that of EDTA (9.16 µg/mL). The maximum absorbance for reducing power assay was found to be 1.928 at 100 µg/mL when compared to 2.449 for standard ascorbic acid. The total phenolic content was 198.81 mg/g of gallic acid equivalent. Acute toxicity test showed that the plant might be safe for pharmacological uses up to a dose level of 3 200 mg/kg of body weight in rats. CONCLUSIONS: Therefore, the obtained results suggest the acute anti-inflammatory and antioxidant activities of the EAV and thus provide the scientific basis for the traditional uses of this plant part as a remedy for inflammations.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Vernonia/química , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Antioxidantes/química , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Etanol/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Histamina/efeitos adversos , Quelantes de Ferro/química , Quelantes de Ferro/farmacologia , Masculino , Óxido Nítrico/antagonistas & inibidores , Oxirredução/efeitos dos fármacos , Fenóis/química , Componentes Aéreos da Planta/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672693

RESUMO

Objective:To investigate the inflammatory and antioxidant activities of ethanolic extract of aerial part of Vernonia patula (Dryand.) Merr (EAV). Methods:The anti-inflammatory activity of EAV was studied using carrageenan and histamine-induced rat paw edema test at different doses (100, 200 and 400 mg/kg body weight). DPPH free radical scavenging, nitric oxide scavenging, reducing power and Fe2+ion chelating ability were used for determining antioxidant activities. Results: The EAV, at the dose of 400 mg/kg, showed a significant anti-inflammatory activity (P Conclusions: Therefore, the obtained results suggest the acute anti-inflammatory and antioxidant activities of the EAV and thus provide the scientific basis for the traditional uses of this plant part as a remedy for inflammations.

20.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 44(2): 193-201, abr.-jun. 2008. graf
Artigo em Português | LILACS | ID: lil-488716

RESUMO

Extratos aquoso e acetônico de 15 frutas foram submetidos a ensaios para investigar a habilidade de seqüestrar o radical estável 1,1-difenil-2-picrilhidrazil (DPPH) e a capacidade de inibir a oxidação em sistema modelo β-caroteno/ácido linoléico. Todas as frutas exibiram propriedade antioxidante, entretanto a ação foi diferenciada entre elas. O extrato aquoso da acerola, caju, mamão "Formosa", mamão Havaí, laranja pêra e goiaba foram os mais eficazes (superior a 70 por cento), enquanto que o do abacaxi, laranja cravo, manga rosa, melão espanhol, melão japonês, melão orange flesh e pinha apresentaram ação moderada (60-70 por cento) e o da manga espada e melancia exibiram a mais fraca capacidade de seqüestrar o radical DPPH. Os extratos acetônico da acerola, caju, pinha e goiaba exibiram uma forte capacidade de seqüestrar o radical DPPH (superior a 70 por cento). Em sistema modelo β-caroteno/ácido linoléico, o extrato aquoso da pinha e o acetônico da goiaba exibiram moderada capacidade antioxidante (60-70 por cento) enquanto que a acerola (extrato aquoso) e o mamão formosa (extrato acetônico) os menores percentuais. Frente à capacidade antioxidante exibida, as frutas podem ser apontadas como fontes de antioxidantes naturais, destacando-se a acerola, caju, mamão Formosa, mamão Havaí, goiaba, laranja pêra, e a pinha por terem apresentado uma potente capacidade antioxidante.


Aqueous and acetone extracts from 15 fruits have been screened for antioxidant activity using DPPH method and ß-carotene/linoleic acid model. All fruits studied showed antioxidant activity, but in different extent. Acerola, cashew-apple, papaya "formosa", papaya "solo", orange and guava showed the higher antioxidant activity (>70 percent) in DPPH method, followed by pineapple, bergamont, mango "rosa", melon "reticulares", melon "inodorus", melon "orange flesh" and sugar-apple aqueous extract (moderate, 60-70 percent) and mango "espada" and watermelon aqueous extract, the lowest activity. Acerola, cashew-apple, sugar-apple and guava acetone extracts exhibited higher scavenging activity toward DPPH radicals (>70 percent).β-carotene/linoleic acid model index of sugar-apple aqueous extract and guava acetone extract demonstrated moderate antioxidant activity (60-70 percent), meanwhile acerola aqueous extract and papaya "formosa" acetone extract the lower. According to antioxidant activity, fruits can be indicated as natural antioxidants sources, pointing out acerola, cashew-apple, papaya "solo", papaya "formosa", guava, orange and sugar-apple as the highest in antioxidant capacity.


Assuntos
Antioxidantes/análise , Frutas/química , Laranja de Acridina , Anacardium , Ananas , Carica , Citrullus , Cucumis melo , Malpighiaceae , Mangifera , Psidium
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