Effect of proteins from the red seaweed Hypnea musciformis (Wulfen) Lamouroux on the growth of human pathogen yeasts

A protein fraction, rich in lectin, obtained from the red seaweed Hypnea musciformis by precipitation with ammonium sulfate (F-40/70) was screened for chitinase and beta-1,3-glucanase activity and assessed for antifungal potential against the human pathogen yeasts Candida albicans and C. guilliermondii. The F-40/70 fraction showed chitinase and beta-1,3-glucanase enzymes, with specific activities of 276.43 and 1880.7 Units.mg (-1) protein, respectively. It was capable of inhibiting the growth of C. guilliermondii at the concentrations of 45, 100 and 450 mu g protein.ml (-1) but it showed only a discrete inhibition against C. albicans irrespective of the tested concentrations. The inhibitory action was shown to be funigistatic and the presence of the glycoprotein fetuin, for which the lectin in the fraction had affinity, abolished the antifungal action. The complete growth recovery following fetuin treatment indicated that chitinase and beta-1,3-glucanase were not involved in the growth inhibition of these yeasts.