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1.
Heliyon ; 4(11): e00957, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30533542

RESUMO

The main goal of the present work was to determine the nutraceutical potential of Asparagopsis taxiformis D. extracts from Madeira Archipelago south coast. Extraction methodologies consisted either/or in 72 hours stirring, at room temperature (M1), or 6 cycles of Soxhlet extraction (M2), both with re-extraction. Solvents used were distilled water, ethanol, methanol and ethyl acetate. M1 allowed to obtain the highest values for extraction yield (31.65 g.100g-1 dw) using water, whereas iodine content (3.37 g.100g-1 dw), TPC (1.71 g GAE.100g-1 dw) and chlorophyll a (45.96 mg.100g-1 dw) were obtained using ethanol, and TCC (36.23 mg.100g-1 dw) with methanol. Extracts that showed higher reduction activity in M1 were derived from ethanol extraction (1,908 mg AAE.100g-1 dw). Water and ethanol were the best solvents for higher DPPH scavenging activity in M2, both with same result (IC50 1.37 mg.mL-1). The lowest value of IC50 for chelating activity (1.57 mg.mL-1) was determined in M1, using ethyl acetate. The remaining residue was used to obtain other products, i.e. lipid extraction (M1, 2.05 g.100g-1 dw), carrageenans (M2, 21.18 g.100g-1 dw) and cellulose (M1, 23.81 g.100g-1 dw) with subsequent FTIR ATR analysis. Our results show that A. taxiformis is a valuable source of bioactive compounds. The M1 extraction methodology using ethanol is the most effective solvent to produce an iodine rich bioactive extract with potential of being used as a nutraceutical supplement. Also, we have demonstrated a possible downstream strategy that could be implemented for multiple compound extraction from A. taxiformis residue. This has a vital importance for future feasibility, when using this biomass as an industrial feedstock for multiple products production. Statistical analysis, using SPSS 24.0, was also performed and important correlations were found between assays and methods.

2.
PLoS One ; 11(6): e0157712, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27314588

RESUMO

Taro (Colocasia esculenta (L.) Schott) is widely distributed in tropical and sub-tropical areas. However, its origin, diversification and dispersal remain unclear. While taro genetic diversity has been documented at the country and regional levels in Asia and the Pacific, few reports are available from Americas and Africa where it has been introduced through human migrations. We used eleven microsatellite markers to investigate the diversity and diversification of taro accessions from nineteen countries in Asia, the Pacific, Africa and America. The highest genetic diversity and number of private alleles were observed in Asian accessions, mainly from India. While taro has been diversified in Asia and the Pacific mostly via sexual reproduction, clonal reproduction with mutation appeared predominant in African and American countries investigated. Bayesian clustering revealed a first genetic group of diploids from the Asia-Pacific region and to a second diploid-triploid group mainly from India. Admixed cultivars between the two genetic pools were also found. In West Africa, most cultivars were found to have originated from India. Only one multi-locus lineage was assigned to the Asian pool, while cultivars in Madagascar originated from India and Indonesia. The South African cultivars shared lineages with Japan. The Caribbean Islands cultivars were found to have originated from the Pacific, while in Costa Rica they were from India or admixed between Indian and Asian groups. Taro dispersal in the different areas of Africa and America is thus discussed in the light of available records of voyages and settlements.


Assuntos
Colocasia/genética , Variação Genética , Repetições de Microssatélites/genética , África , Alelos , América , Ásia
3.
J Helminthol ; 86(3): 368-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21875447

RESUMO

The helminth parasite fauna of the oceanic horse mackerel Trachurus picturatus Bowdich 1825, caught off the Madeira Islands was composed of six different taxa. Prevalence and abundance of larval Anisakis sp. (Nematoda: Anisakidae) and Nybelinia lingualis (Trypanorhyncha: Tentaculariidae), the most common parasite taxa, were 24.3%, 0.9 and 37.9%, 0.7, respectively. Bolbosoma vasculosum (Acanthocephala: Polymorphidae) and the monogeneans Heteraxinoides atlanticus (Monogenea: Heteraxinidae) and Pseudaxine trachuri (Monogenea: Gastrocotylidae) were comparatively rare. The depauperate helminth fauna of the oceanic horse mackerel at Madeira compared to other geographical regions of the north-eastern Atlantic, namely the Azores banks and the West African coast, may be attributed to the paucity of nutrients off oceanic islands and to a low density of the fish population.


Assuntos
Perciformes/parasitologia , Trematódeos/isolamento & purificação , Animais , Portugal
4.
Izv Akad Nauk Ser Biol ; (3): 293-300, 2003.
Artigo em Russo | MEDLINE | ID: mdl-12816060

RESUMO

We studied the influence of metabolites of gamma-aminobutyric shunt of the tricarboxylic acid cycle on the activities of aconitate hydratase (EC.4.2.1.3) as well as NAD- and NADP-specific isocitrate dehydrogenases (EC.1.1.1.41 and EC.1.1.1.42, respectively) using purified enzyme preparations from pea leaves (Pisum sativum L.) and maize scutellum (Zea mays L.). gamma-Aminobutyric acid and succinate proved to have no significant effect on these enzymes, while 0.1-0.2 mM glutamate considerably activated NADP isocitrate dehydrogenase from the both sources, particularly, at unsaturating concentration of the substrate. Succinic semialdehyde stimulated the activities of aconitate hydratase and NADP isocitrate dehydrogenase. The obtained data points to a similar pattern of the effect of intermediates of gamma-aminobutyric shunt on the studied enzymatic activities for both photosynthetic tissues (pea leaves) and those with acidifying, transport, and digestive functions (maize scutellum). However, the absence of pronounced control effects of most metabolites on the studied enzymes allows us to assign them to a relatively inert pool of metabolites.


Assuntos
Aconitato Hidratase/metabolismo , Inibidores Enzimáticos/metabolismo , Isocitrato Desidrogenase/metabolismo , Magnoliopsida/enzimologia , Ácido gama-Aminobutírico/metabolismo , Aconitato Hidratase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Isocitrato Desidrogenase/antagonistas & inibidores , Magnoliopsida/fisiologia , Pisum sativum/enzimologia , Pisum sativum/fisiologia , Folhas de Planta/enzimologia , Folhas de Planta/fisiologia , Zea mays/enzimologia , Zea mays/fisiologia , Ácido gama-Aminobutírico/farmacologia
5.
Biochemistry (Mosc) ; 67(6): 696-705, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12126479

RESUMO

The intensity of free radical processes and the regulation of NADP-isocitrate dehydrogenase (EC 1.1.1.42; NADP-IDH) activity have been studied in the cytoplasmic fraction of normal and ischemized rat myocardium. Chemiluminescence parameters, such as the light sum (S) of slow flash and the tangent of the kinetic curve slope angle (tanalpha1), which characterize the intensity of free radical processes, were increased in ischemia 2.1- and 20.0-fold, respectively. The slow flash intensity (Imax) was increased 22-fold. The contents of lipid peroxidation products--diene conjugates and malonic dialdehyde--were increased 11.9- and 4.7-fold, respectively, suggesting pronounced oxidative stress. Using homogenous enzyme preparations of NADP-IDH isolated from the normal and experimentally ischemized rat myocardium, a number of catalytic properties of the enzyme were characterized for normal and pathologic conditions. NADP-IDH from the normal and ischemized myocardium had the same electrophoretic mobility and was regulated similarly by Fe2+, Cu2+, Zn2+, and also with succinate and fumarate. However, under normal and pathologic conditions NADP-IDH was different in the affinity for substrates and in the sensitivity to inhibitory effects of hydrogen peroxide, reduced glutathione, and of Ca2+. The degree of synergy in the enzyme inhibition with Fe2+ and H2O2 was less pronounced in ischemia. The inhibitory effect of the reaction product 2-oxoglutarate was higher under normal conditions than in ischemia (the Ki values were 0.22 and 0.75 mM, respectively). The specific features of the NADP-IDH regulation in ischemia are suggested to promote the stimulation of the enzyme functioning during increased level of free radical processes, and this seems to be important for NADPH supplying for the glutathione reductase/glutathione peroxidase antioxidant system of cardiomyocytes.


Assuntos
Isocitrato Desidrogenase/metabolismo , Isquemia Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Citoplasma/enzimologia , Ácidos Dicarboxílicos/metabolismo , Eletroforese , Glutationa/metabolismo , Ferro/metabolismo , Isocitrato Desidrogenase/isolamento & purificação , Cinética , Medições Luminescentes , Masculino , Isquemia Miocárdica/enzimologia , Miocárdio/enzimologia , Miócitos Cardíacos/enzimologia , Ratos , Espécies Reativas de Oxigênio/metabolismo
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