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The capsular polysaccharide produced by the thermophilic blue green alga/cyanobacterium Mastigocladus laminosus was tested for its cytotoxic activity against the A431 human epidermoid carcinoma cell line. This polysaccharide inhibited the proliferation of A431 cells in a dose-dependent manner with an IC50 value of 50 μg mL-1. In addition, this polysaccharide strongly inhibited A431 cell migration and invasion. Preliminary experiments showing that secretion of metalloproteinases MMP2 and MMP9 by A431 tumour cells was inhibited by this polysaccharide suggest that this mechanism of action could play a role in its anti-migration and anti-invasive properties. Acid hydrolysis of the polysaccharide produced specific oligosaccharides which conserved - at similar concentrations - their cytotoxic, anti-migration and anti-invasion properties; in this case, the mechanism of action was nevertheless uncorrelated to the decrease of metalloproteinase expression. [ABSTRACT FROM AUTHOR]

A cyanobacterium, Synechocystis sp. PCC 6803, was immobilized by entrapment in poly(vinylalcohol) bearing styrylpyridinium groups. Its properties in a single-compartment micro-photoelectrochemical cell using platinum electrodes in potentiosatic mode were compared with the native material. The operational activity was measured in the presence of an electrolytic solution containing 20 mM sodium phosphate, 0.15 mM NaCl and 1 mM MgCl2. The best conditions of use are pH 7.0, 38 °C and a 2,5-dichlorobenzoquinone concentration equal to 350 μM with native cyanobacteria or pH 6.5, 25 °C and 500 μM 2,5-dichlorobenzoquinone after entrapment. Using this procedure, the photocurrent could be inhibited by pollutants such as Diuron or HgCl2. After entrapment, the detection limits (corresponding to a 10% inhibition) were respectively 0.5 μM and 50 μM for Diuron and HgCl2 after five minutes of incubation. A permeabilization technique was used to increase sensitivity of the procedure to the detection of HgCl2 (25% inhibition with 50 μM after five minutes of incubation). [ABSTRACT FROM AUTHOR]

In a study involving 37 patients with type 2 diabetes mellitus, supplementation with spirulina (8 g/d) for a period of 12 weeks was found to significantly reduce plasma triglyceride and plasma malondialdehyde levels, and increase plasma adiponectin levels. Subjects with higher triglycerides at baseline showed higher reduction in triglycerides and blood pressure, subjects with higher total cholesterol and LDL cholesterol at baseline also showed higher reductions in plasma total cholesterol, LDL cholesterol, IL-6, and blood pressure. The authors conclude, "The results suggest that spirulina is a promising agent as a functional food for diabetes management." [ABSTRACT FROM AUTHOR]