Seaweed-derived foods have long been popular in Korea because of their high content of nutrients that are beneficial to the human body. Recently, Korean seaweeds have been used as raw materials to produce new natural products with health benefits. Herein, we compared the antioxidant activity of 16 Korean seaweed extracts to explore their potential utility as health foods. The total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of seaweed extracts were determined. We also investigated their ability to protect human diploid fibroblast (HDF) cells against hydrogen peroxide. The results showed that seaweed extracts at a concentration of 100 g/mL did not cause any cell toxicity. Sargassum thunbergii (Jichung-i) had the highest TPC and radical scavenging effects, followed by Porphyra tenera (Gim), Silvetia siliquosa (Tteumbugi), and Sargassum fusiforme (Tot). Hydrogen peroxide increased the production of intracellular reactive oxygen species, while P. tenera (Gim), Saccharina japonica (Dasima), and S. thunbergii (Jichung-i) extracts significantly decreased it. The effect was highest in the S. thunbergii (Jichung-i)-treated HDF cells. These findings indicate that S. thunbergii (Jichung-i) shows promise as a potential antioxidant raw material.

Burial sites are constructed for the purpose of controlling air-born livestock diseases such as avian influenza and foot-and-mouth outbreak. As most of the burial sites are located in the agricultural land use, public concerns are mounting about soil and groundwater contamination. During precipitation events, contaminated baseflows are released from the burial sites into surface waters. Baseflow are therefore required to be managed properly, by monitoring and even by remediation means. We propose each burial sites should be regarded as a point source possibly degrade groundwater, thus be managed in watershed scale for the purpose of surface water quality conservation.