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1.
Food Technol Biotechnol ; 58(3): 273-283, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33281483

RESUMO

RESEARCH BACKGROUND: Many plant extracts and essential oils show antibacterial and antifungal activities, with potential to replace the use of synthetic fungicides. We used invasive alien plants goldenrod (Solidago spp.) and Japanese knotweed (Fallopia japonica) as source materials to determine their antifungal activities against seed-associated fungi from wheat grain (Alternaria alternata, Alternaria infectoria, Aspergillus flavus, Epicoccum nigrum and Fusarium poae). EXPERIMENTAL APPROACH: Aqueous and organic extracts (ethanol, methanol and acetone) were prepared from leaves and flowers of S. canadensis, S. gigantea and S. virgaurea, and leaves and rhizomes of F. japonica. Additionally, essential oils were distilled from Solidago flowers and leaves. The extracts and essential oils were tested as inhibitors of fungal growth in vitro. Solidago essential oils were tested also as antifungal agents for protection of wheat grain by determining its fungal infection and germination rate. RESULTS AND CONCLUSIONS: The extracts showed a wide spectrum of low to moderate antifungal activities, with those of Solidago spp. generally more effective than those of F. japonica, and organic extracts more effective than aqueous extracts. The essential oils from leaves and flowers had similar antifungal activity and whole shoots can be collected for their production. This study presents the systematic study of the composition of essential oils from flowers and leaves of three widely distributed Solidago spp. in Slovenia, with the major constituents of terpenes and terpenoids α-pinene, germacrene D and bornyl acetate. NOVELTY AND SCIENTIFIC CONTRIBUTION: The study presents the first use of Solidago spp. and Fallopia japonica extracts and essential oils against fungal strains isolated from wheat grain.

2.
Acta Pharm ; 64(4): 503-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25531790

RESUMO

Due to severe toxicity of pyrrolizidine alkaloids, their quantification in medicinal products is very important. The idea of this research was to use retrorsine as a surrogate reference compound instead of lycopsamine reference or lycopsamine isolated from comfrey. A method for the analysis of lycopsamine in extracts of comfrey roots was developed and validated, employing thin layer chromatography, derivatisation with Dann-Mattocks reagent followed by densitometric analysis. The new method showed linearity within 0.70 to 7.0 µg of lycopsamine per application of 10 µL of a solution. It has also been proven to be specific and precise (repeatability RSD 2-4 % within the plate). The method was successfully employed for quantification of lycopsamine in comfrey root and comfrey root medicinal products such as ointments.


Assuntos
Cromatografia em Camada Fina/métodos , Confrei/química , Densitometria/métodos , Alcaloides de Pirrolizidina/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Raízes de Plantas , Alcaloides de Pirrolizidina/química , Alcaloides de Pirrolizidina/isolamento & purificação , Padrões de Referência
3.
Acta Pharm ; 63(4): 553-60, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24451079

RESUMO

Dried buckwheat herb is used in medicinal products whereas fresh green plant parts, especially sprouts, are consumed as a vegetable. The herb contains fagopyrins, which cause sensitivity to light after ingestion. The aim of this study was to investigate the impact of different growing conditions and the development phase on the content of fagopyrin and phenolic compounds in buckwheat sprouts. Total flavonoid and total phenol contents, fagopyrin content and antioxidant activity were determined spectrophotometrically. Fagopyrin and flavonoids were located almost exclusively in cotyledons. Based on a comparison to hypericin toxicity, the recommendable intake of buckwheat sprouts was estimated to be less than 40 g per day.


Assuntos
Fagopyrum/química , Flavonoides/química , Polifenóis/química , Quinonas/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Dermatite Fototóxica/etiologia , Fagopyrum/efeitos adversos , Fagopyrum/crescimento & desenvolvimento , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Polifenóis/isolamento & purificação , Quinonas/isolamento & purificação , Recomendações Nutricionais , Espectrofotometria
4.
Nat Prod Commun ; 7(7): 861-2, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22908565

RESUMO

An improved method for the isolation and purification of pyrrolizidine alkaloids from comfrey (Symphytum officinale L.) roots was developed, introducing very fast, selective and ion residue-free reduction of N-oxides followed by ion-exchange chromatography giving a non-aqueous solution of alkaloids, from which solvents can be easily removed. With this procedure the use of large volumes of organic solvents, very slow reduction of N-oxides and input of additional impurities was avoided. Lycopsamine, which proved to be the major alkaloid, was additionally purified by preparative layer chromatography (PLC) and high performance liquid chromatography (HPLC). The identity of the alkaloid was confirmed by (I)H NMR spectroscopy and mass spectrometry.


Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Confrei/química , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
5.
J Food Sci ; 77(7): C746-51, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22757696

RESUMO

UNLABELLED: Tartary buckwheat (Fagopyrum tataricum) seeds have a strong aroma that characteristically differs from the aroma of common buckwheat (Fagopyrum esculentum). Its phytochemical background has only been recently investigated. The aim of this study was to identify and quantify individual compounds responsible for tartary buckwheat aroma. Volatiles from different samples (whole seed, flour, and husks) were extracted with simultaneous extraction and distillation by Likens-Nickerson apparatus and analyzed by GC-MS. A total of 48 compounds were quantified and their odor activity values (OAV) were calculated. OAV of 26 compounds was higher than 10; therefore, they significantly contribute to the overall tartary buckwheat aroma. The compounds with OAV > 500 were: (E,E)-2,4-decadienal, (E)-2-nonenal, 2-phenylethanol, (E,E)-2,4-nonadienal, hexanal, decanal, and nonanal. The most important difference from the aroma of common buckwheat is the absence of salicylaldehyde and presence of naphthalene. Salicylaldehyde could be proposed as a marker to detect contamination/adulteration of tartary buckwheat with common buckwheat. PRACTICAL APPLICATION: Buckwheat is becoming one of important alternative crops. Its products which are rich in proteins, fiber, vitamins, and antioxidants have been associated with healthy nutrition. Although tartary buckwheat is similar to more familiar common buckwheat, their characteristic aromas differ notably. This study expands recent research on aroma of tartary buckwheat tea to seed, flour, and husks, and suggests how products from different species of buckwheat can be distinguished by analysis of aroma compounds.


Assuntos
Fagopyrum/química , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Odorantes/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Sementes/química , Compostos Orgânicos Voláteis/análise
6.
Radiol Oncol ; 45(4): 259-66, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22933963

RESUMO

BACKGROUND: Cathepsin H is a cysteine protease considered to play a major role in tumor progression, however, its precise function in tumorigenesis is unclear. Cathepsin H was recently proposed to be involved in processing of bone morphogenetic protein 4 (BMP-4) in mice. In order to clarify whether cathepsin H also regulates BMP-4 in humans, its impact on BMP-4 expression, processing and degradation was investigated in prostate cancer (PC-3), osteosarcoma (HOS) and pro-monocytic (U937) human cell lines. MATERIALS AND METHODS: BMP-4 expression was founded to be regulated by cathepsin H using PCR array technology and confirmed by real time PCR. Immunoassays including Western blot and confocal microscopy were used to evaluate the influence of cathepsin H on BMP-4 processing. RESULTS: In contrast to HOS, the expression of BMP-4 mRNA in U937 and PC3 cells was significantly decreased by cathepsin H. The different regulation of BMP-4 synthesis could be associated with the absence of the mature 28 kDa cathepsin H form in HOS cells, where only the intermediate 30 kDa form was observed. No co-localization of BMP-4 and cathepsin H was observed in human cell lines and the multistep processing of BMP-4 was not altered in the presence of specific cathepsin H inhibitor. Isolated cathepsin H does not cleave mature recombinant BMP-4, neither with its amino- nor its endopeptidase activity. CONCLUSIONS: Our results exclude direct proteolytic processing of BMP-4 by cathepsin H, however, they provide support for its involvement in the regulation of BMP-4 expression.

7.
Phytother Res ; 23(6): 874-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19107742

RESUMO

Lipids are important components in human nutrition; however, their increased intake contributes to the development of obesity and can lead to multiple long-term complications. Pancreatic lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) is a key enzyme for the absorption of dietary triglycerides. Interference with fat hydrolysis results in the reduced utilization of ingested lipids, therefore inhibition of lipases decreases fat absorption. Extracts from 106 species of medicinal plants, vegetables and fruits were screened for potential lipase inhibitory activity. p-Nitrophenylpalmitate and 5-bromo-4-chloro-3-indoxylpalmitate were used as substrates in an in vitro test with crude porcine pancreatic lipase. Bearberry (Arctostaphylos uva-ursi), garden pea (Pisum sativum), Norway spruce (Picea abies) and large-leaved lime (Tilia platyphyllos) extracts were the most active. Additionally, the activity of selected extracts with removed polyphenols was measured. Extracts of bearberry, garden pea and large-leaved lime are a promising source for developing functional foods or isolating active compounds.


Assuntos
Frutas/química , Lipase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Verduras/química , Arctostaphylos/química , Flavonoides/metabolismo , Palmitatos/metabolismo , Pisum sativum/química , Fenóis/metabolismo , Polifenóis , Tilia/química
8.
Food Chem ; 109(2): 293-8, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26003350

RESUMO

Salicylaldehyde (2-hydroxybenzaldehyde) was identified as a characteristic component of buckwheat groats aroma by a sensory analysis guided fractionation of the extract. The extract with the strongest odour was prepared by petroleum ether extraction of water soaked groats. This extract was further extracted with sodium hydrogen carbonate solution and purified by a preparative layer chromatography and identified by NMR, MS and IR spectroscopy. A capillary electrophoresis method was developed and used to determine salicylaldehyde content in buckwheat groats and flour samples. Traditionally dehulled buckwheat grain, which had the strongest odour, contained the highest concentration (1.6ppm) of salicylaldehyde with an odour activity value (OAV) of 216.

9.
J Basic Microbiol ; 46(3): 203-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16721880

RESUMO

Screening new organisms for antibacterial activity and searching for new antibacterial drugs is important due to the constant generation of new antibiotic-resistant strains of pathogenic bacteria. An E. coli broth microdilution test was used to evaluate the results of the Vibrio fischeri bioluminescence test in five of the most antibacterially active species of wood-colonizing fungi. Serpula lacrymans was found to be a potential source of thermostable antibiotic(s) and the Vibrio fischeri bioluminescence test was confirmed to be a useful method for screening for antibacterial activity.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Basidiomycota/metabolismo , Escherichia coli/efeitos dos fármacos , Árvores/microbiologia , Aliivibrio fischeri/fisiologia , Basidiomycota/isolamento & purificação , Temperatura Alta , Luminescência , Testes de Sensibilidade Microbiana/métodos
10.
Eur J Med Chem ; 40(1): 25-49, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15642407

RESUMO

New platelet glycoprotein IIb/IIIa (GP IIb/IIIa, integrin alpha(IIb)beta3) antagonists were prepared on a 2H-1,4-benzoxazine-3(4H)-one scaffold. Their anti-aggregatory activities in human platelet rich plasma and their affinity towards alpha(IIb)beta3 and alpha(V)beta3 integrins were assessed. Various substitution positions and side chain variations were studied. In contrast to the generally accepted model, compounds containing ethyl esters as aspartate mimetics were in general more active than the corresponding free acids. We suggest an explanation for the observed behaviour of these new compounds.


Assuntos
Benzoxazinas/síntese química , Plaquetas/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Receptores de Fibrinogênio/antagonistas & inibidores , Ácido Aspártico , Benzoxazinas/farmacologia , Sítios de Ligação , Plaquetas/química , Desenho de Fármacos , Integrina alfaVbeta3 , Mimetismo Molecular , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/farmacologia , Relação Estrutura-Atividade
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