Extraction of bioactive compounds fromAraucaria angustifoliabracts by microwave‐assisted extraction

Abstract

This study proposed the separation of the phenolic compounds from the bracts by microwave‐assisted extraction at 700, 800, and 1,000 W power, in times of 10, 15, and 20 min using water as a solvent. The results showed that the power and time were significant on the yields of phenolic, tannin, and radical scavenging assay. The best extraction condition was obtained at 1,000 W for 20 min, with contents of 47.61, 27.09, and 779.95 mg/g, for total phenolic compounds, total tannins, and condensed tannins; and 427.28 and 467.79 μmol/g for radical scavenging capacity by ABTS·+ and DPPH·, respectively, and it did not present a significant difference with the exhaustive extraction using acetone as a solvent. The colorimetric parameters Hue angle and Chroma showed values of 62.28° and 31.20, respectively. The maximum predicted responses by response surface methodology were also reached at 1,000 W and 20 min. Practical applications Araucaria angustifolia bracts are a source of phenolic compounds, mainly condensed tannins, which are related to potential health benefits, such as antioxidant capacity and antimicrobial, antimutagenic and anticarcinogenic properties. The extract containing these molecules was obtained by microwave‐assisted extraction using water as a solvent, thus employing green separation technologies, which resulted in shorter residence times at high temperatures and lower losses of thermally sensitive components as well as energy consumption. The results obtained from the recovery of phenolic compounds in the extract demonstrated the feasibility of the method to be applied on the industrial scale for its use in food formulations.

Potential of Pinhão husk (Araucaria angustifolia) as a structural reinforcement agent in the properties of edible films of Pinhão flour and gelatin

“…The moisture content of Pinhão husk was similar to that observed by Spada et al 2 who found a moisture content of 10.3% in Pinhão husk. However, the moisture values obtained in this study were higher than those reported by Timm et al 46 and Dorneles; Noreña, 22 who obtained moisture values of 5.0% and 0.31% for Pinhão husk and bracts, respectively. Furthermore, Timm et al 46 obtained values of lipids and carbohydrates higher than those obtained in this study.…”

“…O. Kuntze is a coniferous plant native to the southern regions of Brazil, northeastern Argentina, and eastern Paraguay. 22 The seed almond corresponds to 74% of its weight 23 Pinhão flour can be considered a good source of starch, presenting between 63.7 and 81.0% of starch and between 5.0 and 6.36% of proteins, 1.0 and 2.2% of lipids, and about 4.7 to 15% of dietary fiber. [23][24][25][26] Some studies have used Pinhão flour or starch as a base for edible films.…”

Mass transfer, kinetics, and thermodynamics studies during the extraction of polyphenols from Feijoa sellowiana peels

“…Doulabi et al identified microwave power and time as effective independent parameters for MAE of bioactive compounds from eggplant peel by-product (Doulabi et al, 2020). Similarly, Dorneles et al determined power and time as main factors for the MAE of bioactive compounds from Araucaria angustifolia bracts (Dorneles & Noreña, 2020). One gram dried sample with 80 ml of 60% ethanol solution was used for each set.…”

Bioactive Activities of the Phenolic Extract from Sterile Bracts of Araucaria angustifolia

“…Freitas et al [ 26 ] observed lower values of the antioxidant capacity using DPPH and ABTS in the phenolic extracts of the pinhão coats obtained by an extraction with pure ethanol (DPPH = 9.14 μmol TE/g; ABTS = 26.4 μmol TE/g) and 80% ethanol solution ( v / v ) (DPPH = 8.62 μmol TE/g; ABTS = 49.10 μmol TE/g). Dorneles and Noreña [ 27 ] evaluated the extraction of the bioactive compounds from the bracts of Araucaria angustifolia employing the aqueous microwave-assisted extraction method (MAE). The authors observed higher levels of antioxidant activity (DPPH = 467.79 μmol TE/g; ABTS = 427.28 μmol TE/g), possibly due to the extraction method, since the parameters used influence the phenolic profile and, consequently, the antioxidant activity of the samples.…”