Phenolic content and antioxidant activity of fruit of Brazilian genotypes of feijoa

Abstract

-The objective of this work was to quantify the total phenolic content (TPC) and total antioxidant activity (TAA) of fruit from Brazilian genotypes of feijoa (Acca sellowiana). Skin and flesh tissues of the fruit were evaluated for the Alcântara, Helena, Mattos, and Nonante cultivars, and for the 2316 accession. TPC and TAA were both assessed in aqueous and hydroalcoholic extracts, and TAA was assayed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] methods. The TPC values, for aqueous extracts of the skin and flesh tissues, were 114.9 and 88.3 mg gallic acid equivalent (GAE) per 100 g fresh weight (FW), respectively. The corresponding values for TAA determined by the DPPH method, the skin and flesh tissues, given as EC 50 (substrate concentration which leads to 50% reduction of the DPPH), were 10.7 and 39.7 mg FW per g DPPH, respectively; and, by the ABTS method, the TAA values were 12.01 and 8.33 µmol L -1 Trolox per g FW, respectively. The greatest values for TPC and TAA were obtained for 'Mattos' and 'Nonante', in the skin, and for 'Nonante' and accession 2316, in the flesh. Feijoa fruit has important functional value, particularly in the skin, characterized by high TPC and TAA.Index terms: Acca sellowiana, Feijoa sellowiana, DPPH and ABTS methods, flesh and skin characterization, functional food. Compostos fenólicos e atividade antioxidante em frutos de genótipos brasileiros de goiabeira-serranaResumo -O objetivo deste trabalho foi avaliar compostos fenólicos totais (CFT) e atividade antioxidante total (AAT) em frutos de genótipos brasileiros de goiabeira-serrana (Acca sellowiana). As avaliações foram realizadas na casca e na polpa dos frutos, nas cultivares Alcântara, Helena, Mattos e Nonante, e no acesso 2316. CFT e AAT foram determinados em soluções extratoras aquosa e hidroalcoólica, e, para AAT, foram utilizados os métodos DPPH (2,2-difenil-1-picrilhidrazilo) e ABTS [2,2'-azino-bis (3-etilbenzotiazolin) 6-ácido sulfônico]. Os valores de CFT em extrato aquoso na casca e na polpa foram de 114,9 e de 88,3 mg em equivalente de ácido gálico (EAG) por 100 g de matéria fresca (MF), respectivamente. Para AAT, em extrato aquoso, na casca e na polpa, no método DPPH, os valores de EC 50 (concentração de substrato para reduzir em 50% a concentração inicial de DPPH) foram de 10,7 e 39,7 mg MF por g de DPPH, respectivamente; e, no método ABTS, foram de 12.01 e 8.33 µmol L -1 de Trolox por g de MF, respectivamente. Os maiores valores de CFT e AAT foram observados em 'Mattos' e 'Nonante', na casca, e em 'Nonante' e no acesso 2316 na polpa. Os frutos de goiabeira-serrana apresentam importante valor funcional, especialmente no tecido da casca, caracterizado pelos elevados conteúdos de CFT e alta AAT.Termos para indexação: Acca sellowiana, Feijoa sellowiana, métodos DPPH e ABTS, caracterização de polpa e casca, alimento funcional.

Physicochemical attributes and functional properties of flowers of Brazilian feijoa genotypes

“…The procedure to obtain the hydroalcoholic extract for quantification of TPC and TAA was described by Amarante et al (2017b). TPC [mg gallic acid equivalents (GAE) 100 g -1 FM] was quantified using the Folin-Ciocalteu method, and TAA was determined based on the ability of the extract to scavenge the radicals ABTS [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)] and DPPH (1,1-diphenyl-2-picrylhydrazyl), as described by Amarante et al (2017b). TAA was expressed as Trolox equivalent antioxidant capacity (TEAC, μmol Trolox g -1 FW) for ABTS method, and as EC 50 (substrate concentration which leads to 50% reduction of DPPH, determined as mg FW g -1 DPPH) for DPPH method.…”

Antibacterial and antioxidant activity of pulp, peel and leaves of Feijoa sellowiana: Effect of extraction techniques, solvents and concentration

“…Similarly, Peng et al (2019) reported that antioxidant activity of New Zealand grown feijoa peel extracts were significantly higher than the whole fruit and flesh extracts. Amarante et al (2017) reported that the feijoa peel extracts exhibited stronger antioxidant activity than the flesh extracts. In the present study, it was observed that antioxidant activity of the feijoa extracts increased with increasing the concentration of extracts and DPPH radical scavenging activity of 5% extracts were higher than 2.5% extracts.…”

Nutritional Characteristics and Antimicrobial Activity of Australian Grown Feijoa (Acca sellowiana)

“…For polyphenols, phenolic acids and flavonoids (e.g., flavone, catechin, quercetin-glycoside, procyanidin B1 and B2) have been found and identified as the major phenolic compounds in the feijoa fruits [4,5,6]. Interestingly, the bioactive components are not only present in the pulp, but also found at a relatively high level in the other biological tissues of the plant such as peel, leaf and flower bud [6,7,8,9]. Although the feijoa fruit peel is edible and can be a rich source of functional ingredients such as polyphenols and pectin fibre [4], it is considered as a by-product of food processing.…”