title: Calcium-Alginate-Inulin Microbeads as Carriers for Aqueous Carqueja Extract.
abstract: Carqueja (Pterospartum tridentatum) is an endemic species and various bioactive compounds have been identified in its aqueous extract. The aim of this study was to protect the natural antioxidants from the aqueous extract of carqueja by encapsulation in Ca-alginate microbeads and Ca-alginate microbeads containing 10% and 20% (w/v) of inulin. The microbeads produced by electrostatic extrusion technique had an average diameter from 625 μm to 830 μm depending on the portion of inulin. The sphericity factor of the hydrogel microbeads had values between 0.014 and 0.026, while freeze dried microbeads had irregular shape, especially those with no excipient. The reduction in microbeads size after freeze drying process (expressed as shrinkage factor) ranged from 0.338 (alginate microbeads with 20% (w/v) of inulin) to 0.523 (plain alginate microbeads). The expressed radical scavenging activity against ABTS and DPPH radicals was found to be between 30% and 40% for encapsulated extract, while the fresh extract showed around 47% and 57% of radical scavenging activity for ABTS and DPPH radicals, respectively. The correlation between antioxidant activity and the total phenolic content were found to be positive (in both assay methods, DPPH and ABTS), which indicate that the addition of inulin didn't have influence on antioxidant activity. The presence of inulin reduced stiffness of the hydrogel, and protected bead structure from collapse upon freeze-drying. Alginate-inulin beads are envisaged to be used for delivery of aqueous P. tridentatum extract in functional food products.
authors.affiliation: Faculty of Technology and Metallurgy, Univ. of Belgrade, Karnegijeva 4, 11000, Belgarde, Serbia.
authors.forename: Bojana
authors.initials: B
authors.lastname: Balanč
authors.affiliation: Faculty of Agriculture, Univ. of Belgrade, Nemanjina 6, 11080, Belgrade, Serbia.
authors.forename: Ana
authors.initials: A
authors.lastname: Kalušević
authors.affiliation: Faculty of Technology and Metallurgy, Univ. of Belgrade, Karnegijeva 4, 11000, Belgarde, Serbia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Drvenica
authors.affiliation: LEAF-Linking Agriculture, Environment, Agriculture and Food, Inst. Superior de Agronomia, Univ. de Lisboa, Tapada da Ajuda, 1349-017, Lisboa, Portugal.|Inst. Politécnico de Castelo Branco, Escola Superior Agrária, Castelo Branco, Quinta da Senhora de Mércules, Apartado 119, 6001-909, Castelo Branco, Portugal.|CERNAS-Centre of Natural Resources, Environment and Society, Bencanta, 3045-601, Coimbra, Portugal.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Coelho
authors.affiliation: Faculty of Technology and Metallurgy, Univ. of Belgrade, Karnegijeva 4, 11000, Belgarde, Serbia.
authors.forename: Verica
authors.initials: V
authors.lastname: Djordjević
authors.affiliation: LEAF-Linking Agriculture, Environment, Agriculture and Food, Inst. Superior de Agronomia, Univ. de Lisboa, Tapada da Ajuda, 1349-017, Lisboa, Portugal.
authors.forename: Vitor D
authors.initials: VD
authors.lastname: Alves
authors.affiliation: LEAF-Linking Agriculture, Environment, Agriculture and Food, Inst. Superior de Agronomia, Univ. de Lisboa, Tapada da Ajuda, 1349-017, Lisboa, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Sousa
authors.affiliation: LEAF-Linking Agriculture, Environment, Agriculture and Food, Inst. Superior de Agronomia, Univ. de Lisboa, Tapada da Ajuda, 1349-017, Lisboa, Portugal.
authors.forename: Margarida
authors.initials: M
authors.lastname: Moldão-Martins
authors.affiliation: Faculty of Agriculture, Univ. of Belgrade, Nemanjina 6, 11080, Belgrade, Serbia.
authors.forename: Vesna
authors.initials: V
authors.lastname: Rakić
authors.affiliation: Faculty of Agriculture, Univ. of Belgrade, Nemanjina 6, 11080, Belgrade, Serbia.
authors.forename: Viktor
authors.initials: V
authors.lastname: Nedović
authors.affiliation: Faculty of Technology and Metallurgy, Univ. of Belgrade, Karnegijeva 4, 11000, Belgarde, Serbia.
authors.forename: Branko
authors.initials: B
authors.lastname: Bugarski
mesh_terms: D000464:Alginates; D000975:Antioxidants / Q000008:administration & dosage* / Q000032:analysis / Q000494:pharmacology; D052160:Benzothiazoles / Q000378:metabolism; D001713:Biphenyl Compounds / Q000378:metabolism; D002118:Calcium; D002214:Capsules; D004337:Drug Carriers; D007887:Fabaceae / Q000737:chemistry*; D005612:Freeze Drying; D055951:Functional Food; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D007444:Inulin; D008863:Microspheres; D010084:Oxidation-Reduction; D010636:Phenols / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology; D010851:Picrates / Q000378:metabolism; D010936:Plant Extracts / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D013451:Sulfonic Acids / Q000378:metabolism
chemical_list: D000464:Alginates; D000975:Antioxidants; D052160:Benzothiazoles; D001713:Biphenyl Compounds; D002214:Capsules; D004337:Drug Carriers; D006603:Hexuronic Acids; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D013451:Sulfonic Acids; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D020723:Glucuronic Acid; D007444:Inulin; C004931:1,1-diphenyl-2-picrylhydrazyl; D002118:Calcium
keywords: Pterospartum tridentatum; alginate; electrostatic extrusion; encapsulation; inulin