Porphyra cell cultures: isolation, growth and polysaccharide production

Actual, potential and speculative applications of seaweed cellular biotechnology: some specific comments on Gelidium

“…Somatic-cell isolation in seaweeds is not a difficult task as it has been achieved by partial enzymatic digestion of thalli (in Porphyra: Tang, 1982;Chen, 1986;Wang et al, , 1987aWang et al, , 1987bTait et al, 1990;Wang & Yan, 1990;Sphacelaria: Ducreux et al, 1988), by cell-wall regeneration from protoplasts (Porphyra: Chen, 1989) or spheroplasts (Undaria: Kapraun & Sherman, 1989), by mechanical disruption of thalli (Prasiola: Schiff et al, 1972;Bingham & Schiff, 1973 ;Gnifithsia: DufEeld et al, 1972;Porphyra, Tait et al, 1990), or of frozen thalli (Porphyra: Zhao & Zhang, 1984), by mechanical disruption of calli (Laminaria: Saga et al, 1978 ; McLean & Connolly, 1989; Alaria: Saga et al, 1978;Undaria: Zhang, 1982) or by combinations of mechanical and enzymatic treatments of both thallus and callus (Pterocladia : Liu & Gordon, 1987).…”

“…Evaluation of axenic cultures do not include tests for viruses, mycoplasma, rickettsia and so forth. Even if judged axenic, contaminants can appear in the cultures after months or years (Fries, 1963;Lee, 1986;Cheney, 1986;Tait et al, 1990), and even with morphologically simple species, there are contradictory results of the eflicacy of sterilization treatments (Bonneau, 1976).…”

“…Nutrient depletion could be the reason for callus and 'callus-like' inductions or reversions (PedersCn, 1968;Fries, 1980;Bradley & Cheney, 1986;Lawlor et al, 1989). Sugars have been reported to be unnecessary or even inhibitory to tissue (Fucus spiralis: Fries, 1984), callus (Ecklonia radiata: Lawlor et al, 1989) and cell culture (Porphyra umbilicalis: Tait et al, 1990) growth or organogenesis. Our studies on the interrelationship between the osmolality of the culture medium and the effect of osmotically active sugar supplementation has shown that, as in higher plants (van Rensburg & Vcelar, 1989), the effects of carbohydrates in seaweed tissue and callus culture seem osmotic or metabolic or both (Robaina et al, 1990a;1990b).…”

“…Although a callus of Gelidium has been obtained with the addition of sucrose (Nakamura, 1974), 20 g 1-' mannitol (Gusev et al, 1987), or in the absence of sugars in the culture media (Polne-Fuller & Gibor, 1987a;Garcia-Reina et al, 1988a), callus production has not occurred in darkness. However, as seaweed tissues, (Fries, 1977;1 98O), cell (Saga et aL, 1978 ;Polne-Fuller et al, 1987 ;Tait et al, 1990) and callus cultures Polne-Fuller & Gibor, 1987b;GarciaReina et al, 1988a;Lawlor et al, 1989) are phototrophic, including Gelidium species, photobioreactors remain a possibility for biomass production.…”

Non-enzymatic isolation of somatic cells fromKappaphycusspp. andEucheuma denticulatum(Solieriaceae, Rhodophyta)

“…Development of new thalli via callus-like growths from isolated cells of a number of green, brown and red seaweeds has been reported by Polne-Fuller & Gibor (1987). Tait et al (1990) were also able to isolate and culture a range of cell lines obtained from tissues of Porphyra umbilicalis. In China, a complete technology system of somatic cell culture, cell attachment techniques and cell immobilization of Porphyra spp.…”