Affiliation:
1. United Graduate School of Agricultural Sciences Kagoshima University Kagoshima Japan
2. Department of Bioscience and Biotechnology, Faculty of Agriculture University of the Ryukyus Nishihara‐cho Japan
3. Center of Molecular Biosciences, Tropical Biosphere Research Center University of the Ryukyus Nishihara‐cho Japan
4. Department of Food Science and Biotechnology, Faculty of Agriculture Kagoshima University Kagoshima Japan
5. Department of Chemistry, Biology and Marine Science, Faculty of Science University of the Ryukyus Nishihara‐cho Japan
6. Bio‐Resources Business Development Division Riken Food Co., Ltd Tagajo‐shi Japan
Abstract
SUMMARYCladosiphon okamuranus is an excellent source of fucoidan among any brown algae spp. However, the structure of polysaccharide varies significantly depending on the species, harvesting season and geographical location. To understand how geographic location affects the structure of cell wall polysaccharide, C. okamuranus cultivated in eight places (Bise, Katsuren, Yonashiro, Shikiya, Karimata, Nishihara, Hisamatsu and Ishigaki) in Ryukyu archipelago were collected during the peak harvesting time and the cell wall polysaccharide was analyzed physiochemically. The cell wall was sequentially fractionated into five fractions and its 80% was consisted of hot water fraction (HW) (60–70%) and hemicellulose‐I fraction (HC‐I) (15–20%), which mainly contained fucoidan composed of fucose (Fuc), glucuronic acid (GlcA) and sulfate (SO3−). Although the chemical composition and molecular weight of fucoidan in HW was slightly different at different places, the composition of Fuc, GlcA and SO3− was constant in the molar ratio of 1.0:0.5:0.7–1.0 respectively, suggesting that relatively similar structural fucoidan from C. okamuranus can be obtained from any geographical location in Okinawa Prefecture during peak time. However, considerable variation in the sugar composition in HC‐I was observed, despite the uniform molecular weight and SO3−. Particularly, HC‐I from Bise, where is the northern part of Okinawa Island, is composed of significantly higher amounts of Glc, Gal, Man, Xyl and morphologically thicker lateral branches compared to algae from the other parts of the island.
Subject
Aquatic Science,Agricultural and Biological Sciences (miscellaneous),Plant Science