Fig. 2

Protoplast isolation from Scytosiphon lomentaria. a Mature macrothalli after 2 months in suspension culture (bar = 1 cm). b Cross section view of macrothallus showing cortex (cx) and medulla (md) (bar = 50 μm). c Plurilocular sporangia (arrows) from a mature macrothallus (bar = 50 μm). d Thallus under enzymatic process showing undigested medulla (md) (bar = 100 μm). e Freshly isolated protoplasts (arrows) from somatic cells and zooids (arrowheads) with flagellum (fl) from digested plurilocular sporangia (bar = 50 μm; bar in inset = 5 μm). f True protoplasts with red chlorophyll autofluorescence under inverted fluorescence microscope showing no cell walls (bar = 10 μm). g Protoplasts with green fluorescence stained with FDA showing their viability (bar = 10 μm)