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Pilaquinga F, Amaguaña D, Morey J, Moncada-Basualto M, Pozo-Martínez J, Olea-Azar C, Fernández L, Espinoza-Montero P, Jara-Negrete E, Meneses L, López F, Debut A, Piña N. Synthesis of Silver Nanoparticles Using Aqueous Leaf Extract of Mimosa albida (Mimosoideae): Characterization and Antioxidant Activity. MATERIALS 2020; 13:ma13030503. [PMID: 31973124 PMCID: PMC7040681 DOI: 10.3390/ma13030503] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/21/2019] [Accepted: 12/22/2019] [Indexed: 12/18/2022]
Abstract
The search for sensitive and rapid analytical techniques for the determination of natural antioxidants is an area in constant growth due, among other aspects, to the complexity of plant matrices. In this study, silver nanoparticles prepared with the aqueous extract of Mimosa albida leaves were used to assess their polyphenolic content and antioxidant capacity. Silver nanoparticles were characterized by different techniques. As a result, nanoparticles of 6.5 ± 3.1 nm were obtained. The total phenolic content in the extract was 1320.4 ± 17.6 mg of gallic acid equivalents GAE. 100 g-1 and in the nanoparticles 257.3 ± 5.1 mg GAE. 100 g-1. From the phenolic profile analyzed by ultra high-performance liquid chromatography (UPLC) with a diode-array detector (DAD), the presence of apigenin and luteolin in the plant extract is postulated. The antioxidant capacity measured by oxygen radical absorbance capacity ORAC-fluorescein assay was 86917 ± 6287 and 7563 ± 967 µmol ET g-1 in the extract and nanoparticles respectively. Electrochemical analysis by cyclic voltammetry (CV) confirmed the effective reduction capacity of the Mimosa albida leaves extract to reduce Ag ions to AgNPs and differential pulse voltammetry (DPV) suggested the presence of two main reducing agents in the extract. From this study, it was concluded that the aqueous extract of Mimosa albida contains reducing agents capable of synthesizing silver nanoparticles, which can be used in the phytochemical industry.
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Affiliation(s)
- Fernanda Pilaquinga
- School of Chemical Sciences, Pontificia Universidad Católica del Ecuador, Av. 12 de octubre 1076, Apartado 17-01-2184, Ecuador; (D.A.); (L.F.); (P.E.-M.); (E.J.-N.); (L.M.)
- Department of Chemistry, University of the Balearic Islands, Cra. de Valldemossa Km. 7.5, 07122 Palma de Mallorca, Spain;
- Correspondence: (F.P.); (N.P.)
| | - Dennis Amaguaña
- School of Chemical Sciences, Pontificia Universidad Católica del Ecuador, Av. 12 de octubre 1076, Apartado 17-01-2184, Ecuador; (D.A.); (L.F.); (P.E.-M.); (E.J.-N.); (L.M.)
| | - Jeroni Morey
- Department of Chemistry, University of the Balearic Islands, Cra. de Valldemossa Km. 7.5, 07122 Palma de Mallorca, Spain;
| | - Mauricio Moncada-Basualto
- Department of Inorganic and Analytical Chemistry, University of Chile, Sergio Livingstone 1007, Independencia, Santiago 233, Chile; (M.M.-B.); (J.P.-M.); (C.O.-A.)
| | - Josué Pozo-Martínez
- Department of Inorganic and Analytical Chemistry, University of Chile, Sergio Livingstone 1007, Independencia, Santiago 233, Chile; (M.M.-B.); (J.P.-M.); (C.O.-A.)
| | - Claudio Olea-Azar
- Department of Inorganic and Analytical Chemistry, University of Chile, Sergio Livingstone 1007, Independencia, Santiago 233, Chile; (M.M.-B.); (J.P.-M.); (C.O.-A.)
| | - Lenys Fernández
- School of Chemical Sciences, Pontificia Universidad Católica del Ecuador, Av. 12 de octubre 1076, Apartado 17-01-2184, Ecuador; (D.A.); (L.F.); (P.E.-M.); (E.J.-N.); (L.M.)
- Departamento de Química, Universidad Simón Bolívar, Apartado, Caracas 89000, Venezuela
| | - Patricio Espinoza-Montero
- School of Chemical Sciences, Pontificia Universidad Católica del Ecuador, Av. 12 de octubre 1076, Apartado 17-01-2184, Ecuador; (D.A.); (L.F.); (P.E.-M.); (E.J.-N.); (L.M.)
| | - Eliza Jara-Negrete
- School of Chemical Sciences, Pontificia Universidad Católica del Ecuador, Av. 12 de octubre 1076, Apartado 17-01-2184, Ecuador; (D.A.); (L.F.); (P.E.-M.); (E.J.-N.); (L.M.)
| | - Lorena Meneses
- School of Chemical Sciences, Pontificia Universidad Católica del Ecuador, Av. 12 de octubre 1076, Apartado 17-01-2184, Ecuador; (D.A.); (L.F.); (P.E.-M.); (E.J.-N.); (L.M.)
| | - Fernanda López
- School of Agricultural & Environmental Sciences, Pontificia Universidad Católica del Ecuador Sede Ibarra, Jorge Guzmán Rueda Ave., Ibarra 100150, Ecuador;
| | - Alexis Debut
- Centro de Nanociencia y Nanotecnología, Universidad de las Fuerzas Armadas ESPE, Sangolqui 170501, Ecuador;
| | - Nieves Piña
- Department of Chemistry, University of the Balearic Islands, Cra. de Valldemossa Km. 7.5, 07122 Palma de Mallorca, Spain;
- Correspondence: (F.P.); (N.P.)
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Functional Properties of Polyphenols in Grains and Effects of Physicochemical Processing on Polyphenols. J FOOD QUALITY 2019. [DOI: 10.1155/2019/2793973] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Phenolic compounds are important products of secondary metabolism in plants. They cannot be synthesized in the human body and are mainly taken from food. Cereals, especially whole grains, are important sources of dietary polyphenols. Compared with vegetables and fruits, the content and biological activities of polyphenols in cereals have long been underestimated. Polyphenols in whole grains are non-nutritive compounds, which are distributed in all structural areas of cereal substances, mainly phenolic acids, flavonoids, and lignans. In recent years, the health effects of whole grains are closely related to their phenolic compounds and their antioxidant activities. Now, different physicochemical processing treatments and their effects have been summarized in order to provide the basis for promoting the development and utilization of food. The various functions of whole grains are closely related to the antioxidant effect of polyphenols. As the basic research on evaluating the antioxidant effect of active substances, in vitro antioxidant tests are faster and more convenient.
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