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1.
Biomed Res Int ; 2018: 6318630, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29581980

RESUMO

Only a few species of the large Astragalus genus, widely used for medicinal purposes, have been thoroughly studied for phytochemical composition. The aim of our research was to investigate the rarely studied species A. glycyphyllos L. and A. cicer L. for the distribution of mineral elements and phytochemicals in whole plants at two growth stages and in morphological fractions. We also investigated the capacity of the plant extracts to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and to chelate ferrous ions. Chemical composition and antioxidant properties depended on species, maturity, and plant part. Herbal material of A. glycyphyllos was richer in Fe, total phenolics, and flavonoids, whereas extracts of A. cicer showed a higher antioxidant activity. Young plants had more isoflavones, showed greater quenching of DPPH radicals, and exhibited better mineral profiles than flowering plants. Among plant parts, leaves were the most valuable plant material according to most characteristics investigated. Isoflavone concentration in flowers was lower than in leaves and stems. None of the Astragalus samples contained detectable amounts of the alkaloid swainsonine. The study demonstrates the potential of plant material from two Astragalus species as a valuable source of iron, phenolic substances including isoflavones, free-radical scavengers, and Fe2+ chelators for pharmaceutical use.


Assuntos
Astrágalo/química , Flores/química , Sequestradores de Radicais Livres/análise , Ferro/análise , Minerais/análise , Folhas de Planta/química , Flavonoides/análise , Fenóis/análise
2.
Molecules ; 24(1)2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30602699

RESUMO

Growing public concerns about health haves prompted the search for novel food sources. The study is focused on the seeds, sprouted seeds and microgreens of Trifolium pratense, T. medium, Medicago sativa, M. lupulina, Onobrychis viciifolia, Astragalus glycyphyllos and A. cicer species as a potential source of value-added food ingredientsr. The samples were analysed for nutritional (wet chemistry, standard methods) and mineral (atomic absorption spectroscopy, UV-Vis spectrophotometry) profiles, isoflavones (ultra-performance liquid with diode array detector ⁻UPLC-DAD), coumestrol (UPLC-DAD), condensed tannins (CT) (vanillin-H2SO4 assay) and triterpene saponins (UPLC with triple-stage quadrupole MS). In our study, each species displayed high, but species-dependent nutritional, mineral and phytochemical value. All counterparts of legumes were mineral and protein rich. A. glycyphyllos samples, especially seeds, were abundant in iron. Trifolium spp. were found to be important sources of isoflavones, Medicago spp. of coumestrol and saponins, and O. viciifolia of CT. The protein and phytochemical contents increased and total carbohydrates decreased from seeds to microgreens.Our findings proved for the first time that seeds, sprouted seeds, and especially microgreens of small-seeded legumes are promising new sources of ingredients for fortification of staple foods with bioactive compounds, minerals and nutrients.


Assuntos
Fabaceae/química , Compostos Fitoquímicos/análise , Sementes/química , Astrágalo/química , Isoflavonas/análise , Medicago/química , Valor Nutritivo , Trifolium/química
3.
J Food Sci Technol ; 54(9): 2661-2669, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28928506

RESUMO

ABSTRACT: Perennial legumes have been used as edible or medicinal plants since ancient times. The focus of the current study are perennial legumes-Trifolium pratense L., T. medium L., Medicago sativa L., M. lupulina L., Onobrychis viciifolia Scop., Astragalus glycyphyllos L. and A. cicer L.-of branching stage as a potential source of value-added ingredients for healthy food. Freeze-dried samples were analysed for proximal composition, mineral, isoflavone and coumestrol contents as well as for antimicrobial activity. Legumes were protein-rich (23.0/100 g on average). Mineral contents in 100 g of plant dry matter averaged: K 2.64 g, Ca 1.81 g, Mg 0.475 g, P 0.324 g, Zn 2.76 mg and Fe 37.8 mg. According to the total amount of phytoestrogens, the species ranked as follows: T. medium (34.4 mg/g) â‰« T. pratense â‰« O. viciifolia ≥ M. sativa = A. cicer = M. lupulina ≥ A. glycyphyllos (0.207 mg/g). Extracts of legumes, especially that of O. viciifolia, exhibited noticeable potency to inhibit the growth of Gram-positive and Gram-negative bacteria. Perennial legumes of branching stage can be used as protein, mineral and phytoestrogen rich source for food ingredients and supplements.

4.
Pharmacogn Mag ; 10(Suppl 1): S181-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24914302

RESUMO

INTRODUCTION: Clover has attracted considerable interest not only as a valuable livestock forage plant, but also as an important source of isoflavones. The current study was aimed to assess the variation of concentration of three isoflavones in clover species grown under a cool temperate climate environment in Lithuania. MATERIALS AND METHODS: Isoflavone contents were quantified in the plant parts of 21 accessions belonging to five perennial species of genus Trifolium (T. pratense, T. repens, T. medium, T. rubens, and T. pannonicum). Daidzein, formononetin, and genistein concentrations were quantified in separate plant parts by reversed-phase high-performance liquid chromatography. The analyte extraction was performed from dried and ground leaves, stems, flowers, and roots. The procedure included acid hydrolysis of isoflavone glycosides to aglycones. RESULTS: According to the averaged sum of the three isoflavones quantified in leaves-stems-flowers, the five clover species ranked as follows: T. medium (7.54-3.62-2.31 mg/g) >T. pratense> T. rubens> T. pannonicum> T. repens (0.191-0.204-0.171 mg/g). The contribution of individual compound to the total isoflavone content depended on the species, accession, and plant part. The major part of the isoflavones is concentrated in leaves or stems; however, there is a great variation also. CONCLUSION: There exists a large variation in the total as well as in individual concentration of isoflavones among the clover species and plant parts and within species. With regard to isoflavone concentration and variability within species, some accessions of T. medium and T. pratense can be considered a highly promising source of phytoestrogens.

5.
Ann Agric Environ Med ; 14(1): 103-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17655186

RESUMO

Fusarium mycotoxins deoxynivalenol (DON), T-2 toxin, and zearalenone (ZEN) contamination in 5 kinds of cereal grain harvested in 2004 and 2005 in different regions of Lithuania was examined for their occurrence frequency and level. In all cereal species DON was the most frequently detected mycotoxin with an incidence rate of 98.0-100% and range in positive samples from traces to 691 microg kg(-1) in 2004 and 62.5-94.0%, range from traces to 1,121 microg kg(-1) in 2005, respectively. All the tested oat samples collected in 2004-2005 were found to be contaminated with the T-2 toxin. In one sample from the year 2004 the level of T-2 toxin (121.5 microg kg(-1)) exceeded the allowable level. In 2004, ZEN contamination was more frequent in spring wheat, barley and oats grain, whereas in 2005 this toxin was identified at higher levels only in barley grain (68.0%). In one barley grain sample from 2004, ZEN content (193.4 microg kg(-1)) exceeded the allowable level. Variation in the relative air-humidity exerted some effect on the incidence of Fusarium spp. fungi and mycotoxin content in wheat grain. The weather conditions at harvesting contributed to an increase in the contents of Fusarium fungi and DON and ZEN mycotoxins produced by them in winter wheat grain. This risk factor increases the threat to human and animal health.


Assuntos
Grão Comestível/química , Contaminação de Alimentos/análise , Fusarium/metabolismo , Micotoxinas/análise , Animais , Qualidade de Produtos para o Consumidor , Microbiologia de Alimentos , Humanos , Lituânia/epidemiologia , Micotoxinas/biossíntese , Fatores de Risco , Toxina T-2/análise , Toxina T-2/biossíntese , Tricotecenos/análise , Tricotecenos/biossíntese , Zearalenona/análise , Zearalenona/biossíntese
6.
Anal Bioanal Chem ; 375(8): 1260-4, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12677348

RESUMO

Methodology for the determination of humus and humic materials content in soil after dichromate oxidation using a multichannel automatic photometer (Multiskan MS) has been developed. The study presented here demonstrates the benefits of using this methodology for the rapid, reliable and accurate determination of humus and humic materials content in various soils. The method is characterised by good data repeatability and low labour and reagent inputs. Photometric estimation is assessed in various respects, and determination procedures are presented. We have compared the data obtained by the titrimetric method and the photometric method with the photometer Multiskan MS. The methods are well correlated. The regression equations and determination coefficients relating to the data obtained by different methods have been calculated. The best statistics of a comparison between the titrimetric ( y) and photometric ( x) methods of humus determination were obtained with a series of standards prepared from the soil samples of known humus content: R(2)=0.99; y=1.05 x-0.37; BIAS=0.24% of humus; SED=0.27% of humus.


Assuntos
Cromatos/metabolismo , Fotometria/instrumentação , Fotometria/métodos , Solo/análise , Oxidantes/metabolismo , Oxirredução , Reprodutibilidade dos Testes , Fatores de Tempo
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