Production of quality biomass of Gelidium micropterum Kützing through optimization of nutrients and salinity for sustainable land-based cultivation
摘要
In this study, the seeding density (w/v), Provasoli Enriched Seawater (PES) medium strength, and salinity of the culture medium were optimized to obtain higher growth rates and superior biomass quality of Gelidium micropterum Kützing. Among the tested seeding densities, 30 mg of biomass per 100 mL of seawater was optimal. The samples cultured in 0 to 100% PES medium strengths at 35 PSU salinity exhibited a daily growth rate (DGR) between 2.73 and 5.79% day−1. A considerably higher DGR of 5.79 ± 0.15% day−1 was obtained by utilizing a 75% PES medium strength. In the salinity experiment, samples cultured with optimized PES medium (75%) at 28 to 36 PSU salinity, showed DGR ranging from 1.84 to 6.20% day−1. The combination of optimized PES medium (75%) and salinity (34 PSU) gave the highest DGR of 6.20 ± 0.04% day−1over other tested combinations. The sample exhibited enhanced levels of total phenols (2.37 ± 0.16 mg GAE g−1 FW), total proteins (20.75 ± 0.27% DW), and total carbohydrates (43.05 ± 0.18% DW) when cultured under optimized culture conditions. The results of this study could offer valuable primary insights for expanding the cultivation of this important alga in tubular photobioreactors and tank systems on land.