Nutritional, chemical and bioactive profiles of different parts of a Portuguese common fig (Ficus carica L.) variety

Abstract

This study aims to give an unprecedented contribution on the chemical composition and bioactivities of the most produced and appreciated Portuguese fig variety ("Pingo de Mel") with the view of expanding the knowledge on its potentialities. An advanced characterization of its peel and pulp parts was carried out. Four free sugars (glucose, fructose, trehalose and sucrose), 5 organic acids (oxalic, quinic, malic, citric, and succinic acids), tocopherols in all their 4 forms, besides 23 fatty acids were detected in the samples. Fifteen different phenolic components were found in the peel hydroethanolic extract; whereas 12 were detected in the pulp hydroethanolic extract. Quercetin-3-O-rutinoside (rutin) was the major constituent of the peel, accounting for 33.8% of its phenolic content, followed by 5-O-caffeoylquinic acid and vanillic acid malonyl di-deoxyhexoside. Caffeic acid derivatives, such as caffeic acid hexosides, were the major components of pulp, followed by vanillic acid derivatives and O-caffeoylquinic acid. Both extracts displayed promising antioxidant capacities in all methods used, namely the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging, the reducing power, the inhibition of β-carotene bleaching assays, the thiobarbituric acid reactive substances assay and the oxidative haemolysis inhibition assay; however, the peel presented significantly lower IC 50 values than pulp. The extracts showed practically identical antibacterial capacities, being effective against methicillin-sensitive Staphylococcus aureus (MICs = 2.5 mg/mL), besides methicillin-resistant S. aureus, Escherichia coli and Morganella morganii (MICs = 5 mg/mL). The obtained results evidence that the fig peel is superior to the corresponding pulp as it relates to nutritional and phenolic profiles as well as bioactivities, endorsing the urgency in valorising and exploiting this usually discarded industrial by-product.

Survey of Phenolic Acids, Flavonoids and In Vitro Antioxidant Potency Between Fig Peels and Pulps: Chemical and Chemometric Approach

“…The same observation was reported with Italian figs by Del Caro and Piga [ 28 ] and Turkish ones where dark-colored fruits were mentioned to have higher levels of total phenols, flavonoids and anthocyanins than the light-colored ones, and those amounts were mainly concentrated in the peels [ 29 ]. The significant difference between cultivars and their fruits peels’ and pulps’ phenolics contents has also been previously found by Harzallah et al [ 30 ] in three fig varieties growing in Tunisia and by Palmeira et al [ 31 ] in the Portuguese variety “Pingo de Mel”. These authors reported that the amounts of phytochemicals compounds are usually dependent not only on the variety but also differ significantly from one fruit part to the other.…”

“…In the industrial processing of figs, the pulp is used, whilst the peel is usually discarded [ 33 ], which generates a significant volume of byproducts consisting mainly of peels. In the studies conducted by Viuda-Martos et al [ 34 ] and Buenrostro-Figueroa et al [ 31 ], it was proven that these byproducts have abundant phytochemical compounds, which suggests their valorization and exploitation as nutraceuticals.…”

Evaluation of the Phenolic Profile of Castanea sativa Mill. By-Products and Their Antioxidant and Antimicrobial Activity against Multiresistant Bacteria

“…Nevertheless, it should be taken into account that other compounds besides phenolic compounds can potentially be present in ethanolic extracts, contributing also to antioxidant properties. Moreover, the synergistic effect of different bioactive compounds present in plants may also enhance the antioxidant properties of the whole extracts [55]. Table 3.…”

Agronomical and quality differences of four fig cultivars grown in Brazil

“…Figs have been grown since ancient time; they are therefore considered sacred in some cultures. Moreover, current researches have already evidenced the health benefits of figs (Palmeira et al, 2019), and Brazil has been lately considered one of the major producers of fig (Ficus carica L.) in the world, as it ranked eleventh with 23.7 thousand tons in 2018 (Food and Agriculture Organization [FAO], 2020).…”