Study on the effects of laminarin, a polysaccharide from seaweed, on gut characteristics

This study investigates whether laminarin (beta 1-3,beta 1-6-glucan), a polysaccharide from seaweed, exhibits beneficial properties for human health by analysing its effects on intestinal parameters. Anaerobic batch culture fermenters were used for the screening of the in vitro utilization of laminarin by the human gut microflora through the monitoring of biochemical and microbiological parameters. Additionally, the influence of laminarin ingestion on the composition of intestinal mucus (neutral mucins, sialomucins and sulphomucins) was studied in rats. Laminarin was almost totally (more than 90% used) fermented after 24 h of incubation with human intestinal bacteria. It was not selectively used by bifidobacteria and lactobacilli, but increased the production of propionate and butyrate. Variations of mucus composition were observed in jejunum, ileum, caecum and colon, both in lumen content and in intestinal wall, of rats after ingestion of this polysaccharide. Due to its effects on mucus composition, laminarin could influence the adherence and the translocation of bacteria across the epithelial wall. In conclusion, laminarin seems to be a modulator of the intestinal metabolism by its effects on mucus composition, intestinal pH and short chain fatty acid (SCFA) production, especially butyrate. (c) 2007 Society of Chemical Industry.