Effect of solvent-solvent partition on antioxidant activity and GC-MS profile of Ilex guayusa Loes. leaves extract and fractions.

The use of guayusa (Ilex guayusa Loes.) leaves as functional food has increase recently. This work discusses the antioxidant activity and volatile compounds of guayusa leaves extract and fractions. The methanol crude extract was obtained by maceration, subsequently hexane, chloroform, ethyl acetate, and aqueous fractions were collected by solvent-solvent partition. Total phenolic content (TPC), total flavonol/flavone content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and ferric reducing antioxidant power (FRAP) were measured by ultraviolet-visible (UV-Vis) spectrophotometry. The results revealed that ethyl acetate fraction showed highest inhibition against DPPH radical (93.86 ± 0.95%) at 500 µg/mL, and reduce the ferric-tripyridyltriazine complex (Fe3+-TPTZ) at 1619.81 mg trolox equivalent (TE)/g, followed by aqueous fraction. This bioactivity could be related to phenolic acids, flavones and flavonols content, as well as the caffeine, dodecanoic acid isopropyl ester, caffeic acid, and malic acid identified by gas chromatography-mass spectrometry (GC-MS). These findings support the antioxidant properties of this plant material.

Anti-inflammatory potential of processing Vernonanthura patens (Kunth) H. Rob. leaves aqueous extract.

Folk medicine uses decoctions of Vernonanthura patens (Kunth) H. Rob. leaves for healing wounds, and moderate pains. In this study, anti-inflammatory activity of decocted aqueous extract and its fractions is discussed. The fractions were obtained by liquid-liquid extraction in a separating funnel with solvents of increasing polarity: hexane, chloroform, and ethyl acetate. Antioxidant capacity, COX1, and COX2 cyclooxygenase inhibitory activities of aqueous extract (A1), aqueous (A2), and ethyl acetate (A3) fractions were assessed. A3 revealed the highest flavonoid content, and DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity. Nevertheless, no significance differences were observed between IC50 values of A1 and A2, and A1 showed anti-inflammatory activity with potential selectivity against COX2 enzyme, but intermediate COX1 inhibition. Further experiments are required to complement the remarkable anti-inflammatory effect of assessed aqueous extract. These results support the medicinal use of this plant species and indicate that A1 can be used as raw material for prospective nutraceutical products.

Effect of Cocoa Bean Shell Addition on Metabolite Profile and Antioxidant Activity of Herbal Infusions.

Cocoa bean shell (CBS) is a by-product with aromatic characteristics that can enhance the aroma and bioactivity of herbal infusions. This study was aimed to determine the effect of the addition of cocoa bean shell on the metabolite profile and antioxidant activity of infusions made with Ilex guayusa and Vernonanthura patens and their mixtures. Metabolite profile was analyzed by gas chromatography-mass spectrometry combined with multivariate analysis. Total polyphenol content and flavonoids were determined by the Folin-Ciocalteu method and by the flavonoid-AlCl3 complex, respectively. Antioxidant activities were measured by the decolorization assay of the 2,2-diphenyl-1-picrylhydrazyl radical and the ferric reducing antioxidant power. The results revealed that the addition of CBS increases the content of phenolic acids in the infusions (caffeic acid, 4-hydroxybenzoic acid, and pyrocatechol). Nonetheless, the antioxidant activity of the infusions decreased with the addition of CBS (16.21 to 2.74 TEAC). Carboxylic acids and derivatives, major compounds present in the infusions prepared with V. patens, were the metabolites that showed the highest correlation with the antioxidant activity. This study suggests that the infusions made with CBS present a profile of metabolites different from the infusions of I. guayusa, V. patens, and their mixtures.

Effect of resin content and pressing temperature on banana pseudo-stem particle boards properties using full factorial design.

The volume of global gross banana exports reached a record of 117.9 million tonnes in 2015 (FAO 2017), which agro-industrial wastes derived as the pseudo-stem, rachis and leaves do not have an industrial application instead they are discarded. This research study applies full factorial design and response surface methodology to determine the effect of pressing temperature and resin content on density (D), moisture (M), water absorption (WA), water swelling (WS), module of rupture (MOR), module of elasticity (MOE) and formaldehyde content (FC) of particle board made of banana pseudo-stem. A 22 factorial design was performed, factors considered were resin and temperature. The low level of resin was 15% in the coarse fiber (CF) and 35% in fine fiber (FF); high level as 25% CF and 45% FF. Temperature levels were 150ºC and 170ºC respectively. The boards met all quality parameters except ones with low resin content that didn't meet WS parameter. Furthermore, resin affected positively on WA, FC and MOE, and decreased D, WS and MOR values. Meanwhile, temperature affected negatively on D, WS, and increased FC, WA, MOE, MOR properties; none of the factors affected M response. Process conditions were optimized to 162.61°C and 43.15% FF, 23.97% CF.