Guava fruit (Psidium guajava L.) as a new source of antioxidant dietary fiber.
Guava (Psidium guajava L.) is a tropical fruit, widely consumed fresh and also processed (beverages, syrup, ice cream, and jams). Pulp and peel fractions were tested, and both showed high content of dietary fiber (48.55-49.42%) and extractable polyphenols (2.62-7.79%). The antioxidant activity of polyphenol compounds was studied, using three complementary methods: (i) free radical DPPH* scavenging, (ii) ferric reducing antioxidant power assay (FRAP), and (iii) inhibition of copper-catalyzed in vitro human low-density lipoprotein (LDL) oxidation. All fractions tested showed a remarkable antioxidant capacity, and this activity was correlated with the corresponding total phenolic content. A 1-g (dry matter) portion of peel contained DPPH* activity, FRAP activity, and inhibition of copper-induced in vitro LDL oxidation, equivalent to 43 mg, 116 mg, and 176 mg of Trolox, respectively. These results indicate that guava could be a suitable source of natural antioxidants. Peel and pulp could also be used to obtain antioxidant dietary fiber (AODF), a new item which combines in a single natural product the properties of dietary fiber and antioxidant compounds.
Jiménez-Escrig
A
A
Departamento de Metabolismo y Nutrición, Instituto del Frío, Consejo Superior de Investigaciones Científicas, Ciudad Universitaria, E 28040 Madrid, Spain. ajescrig@if.csic.es
Rincón
M
M
Pulido
R
R
Saura-Calixto
F
F
D000975:Antioxidants / Q000302:isolation & purification*; D003300:Copper / Q000737:chemistry; D004043:Dietary Fiber; D016166:Free Radical Scavengers / Q000302:isolation & purification; D008077:Lipoproteins, LDL / Q000737:chemistry; D027822:Myrtaceae / Q000737:chemistry*; D010084:Oxidation-Reduction
D000975:Antioxidants; D004043:Dietary Fiber; D016166:Free Radical Scavengers; D008077:Lipoproteins, LDL; D003300:Copper