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1.
Pharmaceuticals (Basel) ; 11(1)2018 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-29361672

RESUMEN

The development of the gastric lesion is complex and the result of the imbalance between aggressive and protective factors, involving the generation of free radicals and disturbance in nitric oxide (NO) production. Sulphated polysaccharides (SP), from marine algae, are widely used in biotechnological and pharmaceutical areas. In this study, we evaluated the effects of SP from the green marine alga Caulerpa mexicana (Cm-SP) in ethanol-induced gastric damage models in mice. Cm-SP (2, 20, or 200 mg/kg), administered p.o., significantly reduced gastric damage, and these effects were inhibited through pretreatment with indomethacin. Cm-SP (200 mg/kg) prevented the ethanol-induced decline in glutathione and restored its normal level. Moreover, it was able to normalize the elevated thiobarbituric acid reactive substance levels. However, Cm-SP did not show any significant effects on NO2/NO3 level, when compared to the ethanol group. The pretreatment with L- NAME induced gastric mucosal damage and did not inhibit the gastroprotective effect of Cm-SP (200 mg/kg). In conclusion, the gastroprotective effects of Cm-SP in mice involve prostaglandins and reduction in the oxidative stress and are independent of NO.

2.
Acta sci., Biol. sci ; 37(1): 31-39, jan.- mar. 2015. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-847978

RESUMEN

The global demand for natural products from seaweeds has increased worldwide; however, no description of the use of isoamly alcohol (IAA) for obtaining of sulfated polysaccharides (SPs) has been reported. We investigated the efficiency of two precipitation methods (M) in obtaining SPs from the red seaweed Gracilaria cornea. SPs enzymatically isolated were concentrated with cetylpyridinium chloride (M I) or IAA (M II) and extracts were examined with regard to their yield, structural features and in vitro effects on the activated partial thromboplastin time (APTT) using normal human plasma and standard heparin (193 IU mg-1). Yield difference reached 12.99%. Quantitative determination of sulfate was similar between the two methods (Ì´26%), but extracts revealed different pattern on charge density by agarose gel electrophoresis. Whereas both extracts revealed as agarocolloids, alternative M II was also efficient for lipids, proteins and nucleic acids according to the infrared analysis. Extracts had virtually no effect on APPT (1.95 and 2 IU mg-1 for M I and M II, respectively). The results revealed IAA as an alternative solvent for obtaining SPs from the red seaweed G. cornea, depending on the industry' usage criterion.


A demanda global de produtos naturais de algas marinhas tem aumentado mundialmente. Entretanto, a obtenção de polissacarídeos sulfatados (PSs) com álcool isoamílico (AIA) não é relatada. Investigou-se a eficiência de dois métodos (M) de precipitação de PSs da alga marinha vermelha Gracilaria cornea. Os PSs isolados enzimaticamente foram concentrados com cloreto cetilpiridimínio (M I) ou AIA (M II). Os extratos foram examinados, segundo seu rendimento, características estruturais e efeitos in vitro sobre o tempo de tromboplastina parcial ativada (TTPA) usando plasma humano normal e heparina padrão (193 UI mg-1). A diferença nos rendimentos foi 12,99% e semelhante determinação quantitativa de sulfato foi obtida entre os métodos (Ì´26%). A eletroforese em gel de agarose revelou diferenças em termos de densidade de cargas entre os extratos. Enquanto ambos os extratos revelaram agarocoloides, o método M II também se mostrou alternativo para lipídios, proteínas e ácidos nucleicos de acordo com a análise de infravermelho. Os extratos praticamente não modificaram o TTPA (1,95 e 2 UI mg-1 para M I e M II, respectivamente). Os resultados revelaram AIA como um solvente alternativo para obtenção de PSs da alga marinha vermelha G. cornea, dependendo do critério de utilização na indústria.


Asunto(s)
Rhodophyta , Algas Marinas
3.
Acta sci., Biol. sci ; 36(2): 137-145, abr.- jun. 2014. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-849058

RESUMEN

Seaweeds have various chemical components with beneficial effects for human use; however, their nutritional values in Brazilian species are not well known. This study aimed to evaluate the content of water, ash, protein, carbohydrate, and lipid in four seaweeds (Hypnea musciformis, Solieria filiformis, Caulerpa cupressoides and C. mexicana). Algal constituents were determined by difference, gravimetric or colorimetric method, being the values expressed as g 100 g-1 dehydrated weight (d.w.). Results revealed that the water (10.7 ± 0.18-15.06 ± 1.14 g 100 g-1 d.w.), ash (7.79 ± 0.87-15.12 ± 0.51 g 100 g-1 d.w), protein (17.12 ± 0.99-20.79 ± 0.58 g 100 g-1 d.w.), lipid (0.33 ± 0.01-3.77 ± 0.13 g 100 g-1 d.w.) and carbohydrate (38.07 ± 0.32-54.24 ± 0.157 g 100 g-1 d.w.) contents varied between the species (p < 0.05). H. musciformis and S. filiformis (Rhodophyta) had highest ash contents (14.14 ± 1.23-15.12 ± 0.51 g 100 g-1 d.w.), whereas lipids were higher for Caulerpa species (Chlorophyta) (1.52 ± 0.17-3.77 ± 0.13 g 100 g-1 d.w.) (p < 0.05). Protein and carbohydrate were the most sources in all the species. Therefore, the studied seaweeds could be a potential source of food ingredients for diets.


As algas marinhas possuem vários componentes químicos com efeitos benéficos para uso humano. Entretanto, não são conhecidos bem seus valores nutricionais em espécies brasileiras. Objetivou-se avaliar os conteúdos de água, cinza, proteína, carboidrato e lipídio em quatro algas marinhas (Hypnea musciformis, Solieria filiformis, Caulerpa cupressoides e C. mexicana). Os constituintes das algas foram determinados por método de diferença, gravimétrico ou colorimétrico, sendo os valores expressos em g 100 g-1 de peso desidratado (p.d.). Os resultados revelaram que os conteúdos de água (10,7 ± 0,18-15,06 ± 1,14 g 100 g-1 p.d.), cinza (7,79 ± 0,87-15,12 ± 0,51 g 100 g-1 p.d.), proteína (17,12 ± 0,99-20,79 ± 0,58 g 100 g-1 p.d.), lipídio (0,33 ± 0,01-3,77 ± 0,13 g 100 g-1 p.d.) e carboidrato (38,07 ± 0,32-54,24 ± 0,157 g 100 g-1 p.d.) variaram entre as espécies (p < 0,05). H. musciformis e S. filiformis (Rhodophyta) tiveram os maiores conteúdos de cinza (14,14 ± 1,23-15,12 ± 0,51 g 100 g-1 p.d.), enquanto as espécies Caulerpa (Chlorophyta) foram para lipídio (1,52 ± 0,17-3,77 ± 0,13 g 100 g-1 p.d.) (p < 0,05). Todas as espécies foram fontes maiores em proteína e carboidrato. Portanto, as algas marinhas estudadas poderiam ser uma fonte de ingrediente alimentar potencial para dietas.


Asunto(s)
Compuestos Químicos , Algas Marinas
4.
Basic Clin Pharmacol Toxicol ; 115(4): 335-42, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24674382

RESUMEN

Sulphated polysaccharides from marine algae are widely used in biotechnological and pharmaceutical areas. In this study, we evaluated the effects of sulphated polysaccharides from the green marine alga Caulerpa mexicana (Cm-SPs) in nociceptive and inflammatory models in rodents. Cm-SPs (10 or 20 mg/kg), administered i.v. in Swiss mice, significantly reduced nociceptive responses, as measured by the number of writhes in response to acetic acid. Cm-SPs (10 or 20 mg/kg) also reduced second-phase responses in the formalin test, but did not exhibit a significant antinociceptive effect in the hot plate test, suggesting that its antinociceptive action occurs through a peripheral mechanism. Cm-SPs (5, 10 or 20 mg/kg), administered s.c. in wistar rats 1 hr before carrageenan, dextran, histamine or serotonin, were tested in paw oedema models. Cm-SPs (10 or 20 mg/kg) reduced carrageenan-induced paw oedema and myeloperoxidase activity in the paw. In addition, Cm-SPs (20 mg/kg) inhibited dextran- or histamine-induced paw oedema, but not serotonin-induced oedema, suggesting that histamine is the major target of Cm-SPs anti-oedematogenic activity. Finally, Cm-SPs (20 mg/kg) administered in mice did not show significant signs of toxicity. In conclusion, Cm-SPs appear to be promising natural modulatory agents for pain and inflammatory conditions.


Asunto(s)
Analgésicos/farmacología , Antiinflamatorios/farmacología , Caulerpa/química , Polisacáridos/farmacología , Animales , Carragenina/efectos adversos , Dextranos/efectos adversos , Modelos Animales de Enfermedad , Edema/inducido químicamente , Edema/tratamiento farmacológico , Femenino , Histamina/efectos adversos , Inflamación/tratamiento farmacológico , Masculino , Ratones , Dolor/tratamiento farmacológico , Dimensión del Dolor , Peroxidasa/metabolismo , Ratas , Ratas Wistar , Serotonina/efectos adversos
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