Study to find the best extraction solvent for use with guava leaves (Psidium guajavaL.) for high antioxidant efficacy

Abstract

The effects of guava leaves extracted using solvents of water, ethanol, methanol, and different concentrations of hydroethanolic solvents on phenolic compounds and flavonoids, and antioxidant properties have been investigated. The antioxidant capability was assessed based on 2,2-diphenyl-1-picrylhydrazyl radical and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical-scavenging abilities, reducing power, and nitric oxide-and nitrate-scavenging activities. The results demonstrated that the antioxidant ability of guava leaf extracts has a strong relationship with phenolic compound content rather than flavonoid content. Phenolic compound content of water extracted guava leaves was higher compared to pure ethanol and methanol extracts. However, phenolic compound content extracted using hydroethanolic solvent was higher than water, whereas 50% hydroethanolic was observed to be the most effective solvent showing high antioxidant ability.

Avaliação da atividade antimicrobiana de extratos de Eugenia anomala e Psidium salutare (Myrtaceae) frente à Escherichia coli e Listeria monocytogenes

“…Pode-se observar que a AA% dos extratos etanólico e de acetato de etila em ambas as espécies vegetais foi maior, onde houve aumento nesta atividade de acordo com o aumento da concentração do extrato analisado, sendo que na maior concentração analisada de 50 µg/mL o extrato (Braga et al, 2014;Castro et al, 2014;Fernandes et al, 2014;Moreno et al, 2014;Seo et al, 2014;Thakur & Arya, 2014).…”

“…O conteúdo de compostos fenólicos, flavonoides e atividade antioxidante estão relacionados com a capacidade de extração de componentes de acordo com o grau de polaridade do solvente e da relação entre soluto e o solvente, sendo que a ação antioxidante é maior em extratos obtidos com solventes mais polares (Turkmen et al, 2006;Carvalho Jr. et al, 2014;Settharaksa et al, 2014).…”

Phytopharmacological overview of Psidium guajava Linn.

“…57 The antioxidant activities of different solvents of P. guajava leaves (water, ethanol, methanol, and various concentrations of hydroethanol) have demonstrated that the antioxidant ability of P. guajava leaf extracts have a strong relationship with phenolic compound when compared to flavonoid content. 58 Aqueous extract of P. guajava and its synthesized TiO 2 nanoparticls are found to possess maximum antioxidant activity and antimicrobial activity when compared with ascorbic acid. 59 Recently, four new compounds, guavinoside C, D, E and F are isolated from the leaves of P. guajava and these compounds showed antioxidant activities in DPPH, 2,2'-azino-bis-3-ethyl benzthiazoline-6-sulphonic acid (ABTS) and ferric reducing antioxidant potential (FRAP) assays.…”

Antioxidant and antimicrobial activities of solvent extract obtained from rocket (Eruca sativa L.) flowers

“…[15][16][17][18][19] In addition, rocket seeds possess a significant free radical scavenging capacity and exert a protective effect against HgCl 2 mediated renal toxicity. 2 Plant solvent extracts may exhibit antimicrobial, [20][21][22] antiinflammatory, 23 fungicidal 24,25 and insecticidal 26 27,28 substituting thereby the synthetic antioxidants restricted in many countries regarding their potential health related issues. 29 Extracting bioactive compounds from rocket leaves and seeds using solvents demonstrated the promising antimicrobial and antioxidant effects of these extracts.…”