Researchers see algae as a promising tool to discover both efficient and safe agents for pain therapy. We evaluated the antinociceptive and anti-inflammatory activities of lectin from the marine alga Pterocladiella capillacea lectin (PcL). PcL was purified and tested in classical models of nociception and inflammation. Male Swiss mice received PcL 30 min prior to receiving 0.8% acetic acid (10 m ml/10 g, i.p.), 1% formalin (20 m ml/intraplantar) or the hot plate test, and were compared to untreated animals or animals pretreated with indomethacin or morphine. PcL (0.9, 8.1 or 72.9 mg/kg, i.v.) significantly reduced the number of writhes (30%, 39%, and 52%, respectively). PcL (72.9 mg/kg, i.v.) also reduced (pϽ Ͻ0.05) both the first and second phases of the formalin test by 58% and 87%, respectively. However, PcL (72.9 mg/kg) did not present significant antinociceptive effects in the hot plate test when compared to morphine, suggesting that its antinociceptive action occurs via peripheral rather than a central-acting mechanism. It was also observed that leukocyte migration was induced by carrageenan (500 m mg/cavity) in male Wistar rats and that PcL (8.1 mg/kg, i.v.) significantly reduced neutrophil migration by 84%, as compared to untreated animals, suggesting inhibition of inflammatory mediators. The data indicated that PcL has peripheral actions with both anti-inflammatory and antinociceptive properties.

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-(Purification and partial characterisation of a lectin from the red marine alga Vidalia obtusiloba C. Agardh). The lectin of the red marine alga Vidalia obtusiloba was purified by a combination of ammonium sulphate precipitation, ionexchange chromatography on DEAE-cellulose and affinity chromatography on cross-linked guar gum. The lectin preferentially agglutinated native and bromelain-treated human group O erythrocytes. The haemagglutinating activity revealed that the lectin was dependent on divalent cations (Ca ++ or Mn ++ ) and was shown to be inhibited by N-acetyl-galactosamine, D-galactosamine, α-lactose and D-galactose and by the glycoprotein porcine stomach mucin. The molecular mass of the lectin, estimated by gel filtration, was 78.9 kDa while by SDS-PAGE, in the presence of β-mercaptoethanol, the lectin exhibited two different protein subunits with M r of 59.6 and 15.2 kDa, suggesting that the lectin is a dimeric protein. Isoelectric focusing revealed the presence of a simple acidic protein with an isoelectric point between 4 and 5. The purified lectin showed a carbohydrate content of 43.2% and a predominance of the amino acids Asp/Asn, Glu/Gln and Leu. The energy of activation (∆G') for the denaturation of the lectin was estimated to be 25.4 kcal.mol -1 at 90 ºC. Immunochemical assays using a rabbit antiserum raised against the purified lectin of V. obtusiloba showed that it was possible to detect the presence of the lectin at different steps of the purification process. Western blotting of SDS-PAGE gels showed immunostaining of only the larger of the lectin subunits.Key words -hemagglutinin, lectin, protein, red marine alga RESUMO -(Purificação e caracterização parcial de uma lectina da alga marinha vermelha Vidalia obtusiloba C. Agardh). A lectina da alga marinha vermelha Vidalia obtusiloba foi purificada através da combinação de precipitação com sulfato de amônio, cromatografia de troca iônica em DEAE-celulose e cromatografia de afinidade em goma de guar reticulada. A lectina preferencialmente aglutinou eritrócitos do grupo humano O, nativos e tratados com bromelaina. A atividade hemaglutinante revelou que a lectina era dependente de cátions divalentes (Ca ++ ou Mn ++ ) e inibida por N-acetil-galactosamina, D-galactosamina, α-lactose and D-galactose e pela glicoproteína mucina de estômago de porco. A massa molecular da lectina, estimada por filtração em gel, foi de 78,9 kDa, enquanto por SDS-PAGE, em presença de β-mercaptoetanol, a lectina exibiu duas subunidades protéicas diferentes com Mr de 59,6 e 15,2 kDa, sugerindo que a lectina é uma proteína dimérica. Focalização isoelétrica revelou a presença de uma proteína ácida simples, com um ponto isoelétrico entre 4 e 5. A lectina purificada exibiu um conteúdo de carboidrato de 43,2% e uma predominância dos aminoácidos Asp/Asn, Glu/Gln e Leu. A energia de ativação (∆G') para a desnaturação da lectina foi calculada como sendo 25,4 kcalm.mol -1 a 90 ºC. Ensaios imunoquímicos usando um anti-soro de coelho produzido contra a lectina purificada de...