title: Optimization of alginate alkaline extraction technology from Sargassum latifolium and its potential antioxidant and emulsifying properties.
abstract: Alginate was recovered from Sargassum latifolium biomass using different conditions of alkali treatment. Box-Behnken experimental design was evaluated to study the influence of alkali:alga ratio, temperature and time on alginate yield, and its molecular weight (MW) and mannuronic/guluronic acid ratio (M/G). The second-order polynomial equations were analyzed by appropriate statistical methods. Extraction temperature and time were the most important factors during alginate alkaline extraction. MW and M/G ratio played an important role in controlling the reducing power of alginate. Increasing pH of the alginate solutions enhanced its reducing capacity, while thermal treatment showed a negative effect. Additionally, alginate exhibited good emulsion stabilizing capacities with diverse hydrophobic compounds. Emulsifying activity was less sensitive to temperature, ionic strength and more stable at acidic pH.
authors.affiliation: Botany and Microbiology Department, Faculty of Science, Assiut University, 71516 Assiut, Egypt.
authors.forename: Mustafa A
authors.initials: MA
authors.lastname: Fawzy
authors.affiliation: Botany and Microbiology Department, Faculty of Science, Assiut University, 71516 Assiut, Egypt. Electronic address: m_gomaa@aun.edu.eg.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Gomaa
authors.affiliation: Botany and Microbiology Department, Faculty of Science, Assiut University, 71516 Assiut, Egypt.
authors.forename: Awatief F
authors.initials: AF
authors.lastname: Hifney
authors.affiliation: Botany and Microbiology Department, Faculty of Science, Assiut University, 71516 Assiut, Egypt.
authors.forename: Khayria M
authors.initials: KM
authors.lastname: Abdel-Gawad
mesh_terms: D000464:Alginates / Q000302:isolation & purification*; D000975:Antioxidants / Q000737:chemistry*; D045703:Emulsifying Agents / Q000737:chemistry*; D020723:Glucuronic Acid / Q000302:isolation & purification; D006603:Hexuronic Acids / Q000302:isolation & purification; D044647:Sargassum / Q000737:chemistry*
chemical_list: D000464:Alginates; D000975:Antioxidants; D045703:Emulsifying Agents; D006603:Hexuronic Acids; D020723:Glucuronic Acid
keywords: Alkaline treatment; Antioxidant stability; Citric acid (PubChem CID: 311); Emulsifying activity; Ethanol (PubChem CID: 702); FTIR; Iron trichloride (PubChem CID: 24380); M/G ratio; Potassium ferricyanide (PubChem CID: 26250); Sodium alginate; Sodium alginate (PubChem CID: 5102882); Sodium carbonate (PubChem CID: 10340); Trichloroacetic acid (PubChem CID: 6421); d-Mannuronic acid (PubChem CID: 439630); l-Guluronic acid (PubChem CID: 6857369)