The brown seaweed Sargassum fusiforme is an edible and highly valued in Korea. During the summer season, phytal organisms graze heavily on young algal blades and holdfastsof the species and substantially reduce harvestable biomass. Here, in this study, we investigated the effects of pH (range: 2~13) and salinity (range: 0~44 psu) on the removal of two major phytal animals, Caprella scaura and Gammaropsis utinomi, associated with S. fusiforme. We also examined the optimum quantum yield (Fv/Fm) of algae in the same experimental conditions to quantify the tolerance of algae to acid and salinity treatments. It was observed that the phytal animals showed more than 80% mortality at pH lower that pH 4 and the extreams of salinity (0~10 psu and 44 psu) after a 5 min of immersion. However, the quantum yield of S. fusiforme was not significantly different from controls within the pH 3~11 range, and the 0~44 psu salinity range. Precisely, if the pH and salinity conditions outside these ranges were used in comercial Sargassum culture, the removal of the animal species would be higher, but with reduced quantum yield of algae. Taken together, our study results indicated that the pH and salinity treatments could allow multiple harvests from the same holdfast of S. fusiforme.

Sargassum fusiforme has traditionally been widely consumed in Asia as a food, and it has gained much attention due to its high nutritional, pharmaceutical, and industrial value. This study aimed to examine the promotional effects of ethanol extract (ET) and fraction obtained from ethyl acetate (FR) of S. fusiforme on hair growth in C57BL/6 mice and HaCaT cells. Five-week-old mice were used to compare hair regrowth during application of ET and FR for 21 days. Hair regrowth was evaluated by macroscopic observation and verified by hematoxylin-eosin tissue staining. Levels of mRNA expression of factors relevant to the hair growth cycle such as keratinocyte growth factor (KGF), vascular endothelial growth factor (VEGF), and transforming growth factor-beta1 (TGF-β1) were examined by quantitative polymerase chain reaction (qPCR). Our results showed that ET and FR successfully promoted hair regrowth in shaved C57BL/6 mice at a dose >20 mg/kg. Moreover, ET and FR were effective in stimulating expression of KGF and VEGF mRNAs in a dose-dependent manner, whereas TGF-β1 was not activated. These results indicate that ET and FR of S. fusiforme effectively promoted hair growth and gene expression relevant to hair growth cycles in both in vitro and in vivo models.