Seasonal variation in nutritional composition and anti-proliferative activity of brown seaweed, Sargassum oligocystum

Abstract

This study investigated the nutritional components and anti-proliferative activity of Sargassum oligocystum against an adriamycin-resistant human small cell lung carcinoma cell line (GLC4/Adr). The seaweed samples were collected from Nang Rong Beach, Chonburi Province, Thailand in February (the hot/dry season), May (the early monsoon season), August (the monsoon season) and December (the cool/dry season) of 2012. In general, the nutritional composition of S. oligocystum was high during the hot dry and early monsoon season. Additionally, four different types of extract were obtained: ethanolic extract (E1), lipophilic extract (E2), acidic extract (E3) and alkali extract (E4). The highest anti-proliferative activity was found in samples collected during the monsoon season. It is noteworthy that the E2 extract collected during the monsoon season was the most effective, with an IC50 (half maximal inhibitory concentration) value of 2.52 ± 0.54 μg mL−1. The anti-proliferative activity showed a positive correlation with vitamin E (α-tocopherol) in the extracts. However, there were no clear correlations between the total phenolic or fucoxanthin contents and anti-proliferative activity. These results indicate that S. oligocystum has potential as an alternative source for functional food or cancer treatments in the future.