Formaldehyde treatment is used to remove all those phenolic compounds while extracting the alginate from the brown seaweed. My purpose is to fabricate a biomaterial by merging the alginate that extracted from brown seaweed and the collagen that extracted from fish.
Alginates are cell-wall constituents of brown algae (Phaeophyceae). They are chain-forming heteropolysaccharides made up of blocks of mannuronic acid and other acids.Alginate, sometimes shortened to "algin", is present in the cell walls of brown seaweeds, and it is partly responsible for the flexibility of the seaweed. Sodium alginate is isolated from Moroccan Laminaria digitata brown seaweed . The extraction yield is affected by the extraction temperature and the samples’ size.Extraction is done according to Calumpong et al. (1999) with some small modifications. Samples are dried to constant weight at 60 °C in an oven, soaked for one night in a 2% formaldehyde solution to eliminate pigments, then wash with distilled water and add to a 0.2 M HCl solution before being set aside for 24 h.After this period, the samples should wash once again with distilled water before being extracted under agitation for 5 h with a 2% sodium carbonate solution.The supernatants collected after different extraction periods are eliminated by centrifugation. Sodium alginate is precipitated with ethanol. At the end, sodium alginate is purified twice with ethanol, then with methanol and acetone before been dried at room temperature.
iT WOULD SEEM THAT LARGE SCALE PROCESSORS OF ALGINATE STILL ADD FORMALDEHYDE TO THE SEAWEEDS.
Yes! In principle you ca avoid using formaldehyde but if you do not block the REDOX reactions you will not get good alginate.
- Badges
- Science topic
- Similar topics
- Phytochemistry
- Extracts