The samples
were incubated in an antibiotic solution: 100 mg L−1 penicillin G
and 100 mg L−1 streptomycin sulfate in 50% of Provasoli’s enriched
seawater (PES) medium (Provasoli, 1968) for 48 h. The samples
were then washed with 3.0 g L−1 povidone iodine and 15% ethanol
for 30 s, followed by rinsing with autoclaved seawater.