Culture medium composition for optimal thallus regeneration in the red alga Asparagopsis armata Harvey (Rhodophyta, Bonnemaisoniaceae)

The formation and the growth of regenerated fronds from cultivated barbs of Asparagoysis armata were investigated according to an experimental design methodology. A maximal ratio of 3.3 mm regeneration/mm barb was reached for two media constituted of seawater complemented with iron sulfate, EDTA and potassium bromide. The first optimal medium was composed of [FeSO(4)7H(2)O] = 0.20 mg L-1, [Na(2)EDTA2H(2)O] = 2.9 mg L-1, [KBr] = 12.0 mg L-1 and the second one of [FeSO(4)7H(2)O] = 0.2 mg L-1, [Na(2)EDTA2H(2)O] 4.6 mg L-1, [KBr] = 28.7 mg L-1. Barbs excised from adult thalli were placed for 4 weeks in seawater enriched with several chemical substances at different concentrations. The experimental procedure involved: 1) the screening of the influencing compounds with an Hadamard design and 2) the investigation of their optimal concentrations according to a Doehlert design of response surface methodology.