Low molecular weight polysaccharides can be isolated from Sargassum thunbergii (LMPST) and in vitro experiments were conducted to evaluate the inhibitory effects on lipids. Two natures of LMPST were attained from S. thunbergii and appraised their LMPST on palmitic acid (PA) induced lipid accretion in HepG2, and 3T3-L1 cells. LMPST treatment lessened lipid deposition and intracellular free fatty acid and triglyceride intensities in PA-treated above mentioned cells. The mechanistic study publicized that LMPST2 significantly suppressed adipogenesis and stimulated the PA-treated 3T3-L1 cells occupied in the lipolysis pathway. Furthermore, in PA-treated HepG2 cells, the free fatty acid oxidation was significantly increased by LMPST2. Given these constructive properties of LMPST2 from S. thunbergii, is a potential candidate for diminishing the intracellular lipids, and for a therapeutic agent in those conditions.

The prevalence of obesity has increased and is a health concern worldwide. Due to the concerns regarding synthetic anti-obesity treatments, nowadays natural products become a trend. Previous studies proved that there is a potential to use marine algae as anti-obesity agents. Therefore, in this study, the lipid inhibitory effect of crude polysaccharide of amyloglucosidase-assisted hydrolysate from Sargassum thunbergii (STAC) and its fucoidan fractions (STAFs) on 3T3-L1 cells and high-fat diet (HFD)-induced obese mice were investigated. According to the results, the STAF3, showed the highest xylose content and exhibited significant inhibitory effects on lipid accumulation by downregulating adipogenic and lipogenic proteins in 3T3-L1 cells. Furthermore, oral supplementation with STAC significantly declined gain in body weight and fat weight, and serum lipid contents in an HFD-induced obesity mouse model. Structural and chemical characterizations demonstrated that purified STAF3 has consistent surface morphology and small particle size, with similar structural characteristics as commercial fucoidan. Together, these results indicate that STAC and purified STAF3 from Sargassum thunbergia is a potent source to develop as ananti-obesity agents or functional food products to counter obesity.

Seaweeds play a vital role as a source of food and ingredients in traditional Korean medicine. Koreans consume seaweed as fresh vegetables, salad, soups, or snacks. There are several edible brown seaweed species are abundant along the shores of the Korean peninsula, such as Ecklonia cava, Hizikia fusiforme, Laminaria japonica, Pelvetia siliquosa, Sargassum fulvellum, and Undaria pinnatifida. With the growing body of scientific evidence, it is clear that these brown seaweeds are not only good substitutes for land vegetables but also a good source of bioactive secondary metabolites. The secondary metabolites identified from edible Korean brown seaweeds (phlorotannins, sulfated polysaccharides, pigments, and sterols) have the potential to be developed as functional food ingredients. However, seaweeds consumption and their industrial level applications as functional materials are limited compared to the land vegetables. Insufficient awareness about health benefits of seaweeds might be the reason for this issue. Thus, in this review health promotion properties associated with edible Korean brown seaweeds are summarized. The present study might therefore increase consumption and industrial use of brown seaweeds.