title: Effects of extraction methods on molecular characteristics, antioxidant properties and immunomodulation of alginates from Sargassum angustifolium.
abstract: The relationship between molecular structure and bioactivity was evaluated for alginates obtained under different extraction methods (water, acid, alcalase and cellulase) from Sargassum angustifolium. The use of enzymes considerably reduced protein (from 14.58% to <0.4%) and polyphenol (from 16.0% to <1.7mg GA/g sample) contaminations of alginates compared to those of water and acid. The FT-IR spectrum revealed that extraction method did not affect the structure of the recovered alginates. The highest molecular weight (Mw) (557.1×103g/mol) was found in acid treated alginate while the Mwof cellulase assistant alginate (356.2×103g/mol) was the minimum. The SVgvalues varied from 2.79-5.17cm3/g revealing the loosed conformational structures of alcalase and cellulase assistant alginates. Alcalase assistant alginate stimulated RAW264.7 cells to release nitric oxide and inflammatory cytokines TNF-α, IL-1, IL-6, IL-10 and IL-12. Enzyme treated alginates showed maximum DPPH radical scavenging activity and reducing power. Therefore, the present results showed the determinant effect of pretreatment during the extraction process of alginate and the beneficial influence of enzymatic process when biological functions of alginates are of high interest in the industry.
authors.affiliation: Department of Seafood Processing, Faculty of Marine Sciences, Tarbiat Modares University, P.O. Box 46414-356, Noor, Iran.
authors.forename: Niloofar Jokar
authors.initials: NJ
authors.lastname: Borazjani
authors.affiliation: Department of Seafood Processing, Faculty of Marine Sciences, Tarbiat Modares University, P.O. Box 46414-356, Noor, Iran. Electronic address: m.tabarsa@modares.ac.ir.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Tabarsa
authors.affiliation: Department of Marine Food Science and Technology, Gangneung-Wonju National University, Gangneung, Gangwon 25457, Republic of Korea.
authors.forename: SangGuan
authors.initials: S
authors.lastname: You
authors.affiliation: Department of Seafood Processing, Faculty of Marine Sciences, Tarbiat Modares University, P.O. Box 46414-356, Noor, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Rezaei
mesh_terms: D000464:Alginates / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D001713:Biphenyl Compounds / Q000737:chemistry; D005591:Chemical Fractionation / Q000379:methods*; D020723:Glucuronic Acid / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D006603:Hexuronic Acids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007155:Immunologic Factors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008970:Molecular Weight; D009569:Nitric Oxide / Q000096:biosynthesis; D010851:Picrates / Q000737:chemistry; D000067996:RAW 264.7 Cells; D044647:Sargassum / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D000464:Alginates; D000975:Antioxidants; D001713:Biphenyl Compounds; D006603:Hexuronic Acids; D007155:Immunologic Factors; D010851:Picrates; D014867:Water; D009569:Nitric Oxide; D020723:Glucuronic Acid; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: Alginates; Extraction process; Immunomodulatory; Molecular weight; Sargassum angustifolium