Porphyra cell cultures: isolation,growth and polysaccharide production

A range of cell lines was isolated fromPorphyra umbilicalis L. (Rhodophyta) tissue using a variety of methods, the most successful involving exposure to a limpet acetone powder enzyme extract for 24 h, homogenisation and filtration through a series of polyester meshes. All established lines grew as 0.1–5 mm diameter aggregates in liquid culture; most were stable and have been grown in shake-flask or air-lift culture for periods in excess of 1 yr without reverting to the foliose growth form. An investigation of the medium used to grow these lines indicated that it was not nitrogen-deficient and that the sodium chloride concentration was optimal. The addition of an organic buffer increased the final cell yield. None of these cell lines grew heterotrophically in medium supplemented with a range of fixed carbon sources. The infrared spectra of polysaccharides isolated fromPorphyra aggregates and from tissue grown under identical conditions indicated that the structures of the two isolates were analogous.Presented at the XIIIth International Seaweed Symposium, University of British Columbia, Vancouver, Canada, August 1989.