Absorbent bioactive aerogels based on germinated wheat starch and grape skin extract.

This study aimed to produce water-absorbent bioactive aerogels using biodegradable raw materials, wheat starch and poly ethylene oxide (PEO), and derived from agro-industrial residues (grape skin) obtained in the wine industry. The aerogels were produced using germinated wheat starch (GWS), with and without PEO, and incorporating grape skin extract (GSE) at concentrations of 5 and 10 % (w/w). The GSE was evaluated for total and individual phenolic compounds, anthocyanins, and antioxidant activity. The starch aerogels were characterized for morphology, density, porosity, functional groups by FT-IR, relative crystallinity and diffraction pattern, water absorption capacity, antioxidant activity, and in vitro release profile of phenolic compounds in food simulant medium. The total phenolic compounds in GSE was 226.25 ± 0.01 mg equivalent of gallic acid/g GSE. The aerogels showed low density and high porosity. All aerogels demonstrated high water absorption capacity (581.4 to 997.5 %). The antioxidant activity of the aerogels increased with increasing GSE concentration and the addition of PEO. The aerogels could release GSE gradually for up to 120 days in the hydrophilic simulant medium and 240 h for the hydrophobic medium. Starch-based aerogels with GSE showed potential to be applied as exudate absorbers with antioxidant activity to develop active food packaging.

Curcumin encapsulation in capsules and fibers of potato starch by electrospraying and electrospinning: Thermal resistance and antioxidant activity.

The aim of this work was to encapsulate curcumin at different concentrations in capsules and fibers of native potato starch by electrospraying and electrospinning. The best conditions for the production of capsules and fibers were obtained by varying the polymer concentration and resting time of the polymer solution. The best conditions were used for the encapsulation of curcumin. The curcumin-loaded capsules and fibers had an average diameter of 1373 nm to 1787 nm and 108 nm to 142 nm, respectively, and had a high curcumin loading capacity with values ranging from 79.01 % to 97.09 %. Curcumin encapsulated in starch capsules and fibers showed higher thermal stability at 180 °C for 2 h compared to unencapsulated curcumin. The antioxidant activity of starch fibers containing 1 % of curcumin had the greatest ability to inhibit the ABTS radical (45 % inhibition). These materials are promising for use in food or active packaging.

Characterization and quantification of bioactive compounds from Ilex paraguariensis residue by HPLC-ESI-QTOF-MS from plants cultivated under different cultivation systems.

Ilex paraguariensis is a perennial plant used in the production of mate tea, "chimarrão" and "tererê," cosmetics, and other food products. Its leaves are harvested every 12 or 18 months. Approximately 2 to 5 tons of residue are generated per hectare during the harvest. The bioactive composition of this residue has not been characterized to date. Therefore, this paper presents for the first time, the simultaneous characterization of the bioactive compounds of the leaves, thin branches, and thick branches (residue) from I. paraguariensis grown under two cultivation systems: "full sun" and "shaded." The identification and quantification of the compounds was performed using high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight mass spectrometer (HPLC-ESI-QTOF-MS). Consequently, 35 compounds were identified. The average dry weight of phenolic compounds in the residue was 4.1 g/100 g, whereas that in the bark of the residue was 12.9 g/100 g, which was similar to the content found in leaves. The same compounds were identified in the two cultivation systems but with a difference in their contents. While the "full sun" cultivation had a higher content of phenolic acids, the "shaded" cultivation had a higher content of flavonoids and saponins. It was found that the I. paraguariensis residue, particularly the bark, is rich in bioactive compounds, such as quinic, 3-caffeoylquinic, 5-cafefoylquinic, 3,5-dicaffeoylquinic, and 4,5-dicaffeoylquinic acids as well as rutin, and their contents vary according to the cultivation system. Therefore, this residue is an underutilized natural resource with a potential for industrial applications. PRACTICAL APPLICATION: Yerba mate producers will be able to choose the best cultivation system ("full sun" or "shaded") to increase the content of bioactive compounds. New products may be developed with yerba mate residue due to its high concentration of compounds that are beneficial to the human health. New destinations may be applied to yerba mate residue from the harvest pruning, adding commercial value to this unexplored natural resource.

Production, Characterization, and Stability of Orange or Eucalyptus Essential Oil/ß-Cyclodextrin Inclusion Complex.

The aim of this study was to produce and characterize inclusion complexes (IC) between ß-cyclodextrin (ß-CD) and orange essential oil (OEO) or eucalyptus essential oil (EEO), and to compare these with their pure compounds and physical mixtures. The samples were evaluated by chemical composition, morphology, thermal stability, and volatile compounds by static headspace-gas chromatography (SH-GC). Comparing the free essential oil and physical mixture with the inclusion complex, of both essential oils (OEO and EEO), it was observed differences occurred in the chemical composition, thermal stability, and morphology. These differences show that there was the formation of the inclusion complex and demonstrate the necessity of the precipitation method used to guarantee the interaction between ß-CD and essential oils. The slow loss of the volatile compounds from both essential oils, when complexed with ß-CD, showed a higher stability when compared with their physical mixtures and free essential oils. Therefore, the results showed that the chemical composition, molecular size, and structure of the essential oils influence the characteristics of the inclusion complexes. The application of the ß-CD in the formation of inclusion complexes with essential oils can expand the potential applications in foods.