Propolis is a complex mixture of resinous and balsamic material collected from the exudates of plants, shoots, and leaves by bees. This study evaluated red propolis extracts obtained by conventional (ethanolic) extraction and ultrasound-assisted extraction of six samples from different regions of northeastern Brazil. The total phenolic compounds and flavonoids, in vitro antioxidant activity, concentration of formononetin and kaempferol and the cytotoxicity against four human tumor cell lines were determined for all twelve obtained extracts. Significant variations in the levels of the investigated compounds were identified in the red propolis extracts, confirming that the chemical composition varied according to the sampling region. The extraction method used also influenced the resulting propolis compounds. The highest concentration of the compounds of interest and the highest in vitro antioxidant activity were exhibited by the extracts obtained from samples from state of Alagoas. Formononetin and kaempferol were identified in all samples. The highest formononetin concentrations were identified in extracts obtained by ultrasound, thus indicating a greater selectivity for the extraction of this compound by this method. Regarding cytotoxic activity, for the HCT-116 line, all of the extracts showed an inhibition of greater than 90%, whereas for the HL-60 and PC3 lines, the minimum identified was 80%. In general, there was no significant difference (p>0.05) in the antiproliferative potential when comparing the extraction methods. The results showed that the composition of Brazilian red propolis varies significantly depending on the geographical origin and that the method used influences the resulting compounds that are present in propolis. However, regardless of the geographical origin and the extraction method used, all the red propolis samples studied presented great biological potential and high antioxidant activity. Furthermore, the ultrasound-assisted method can be efficiently applied to obtain extracts of red propolis more quickly and with high concentration of biomarkers of interest.

Interest in nanocellulose obtained from natural resources has grown, mainly due to the characteristics that these materials provide when incorporated in biodegradable films as an alternative for the improvement of the properties of nanocomposites. The main purpose of this work was to investigate the effect of the incorporation of nanocellulose obtained from different fibers (corncob, corn husk, coconut shell, and wheat bran) into the chitosan/glycerol films. The nanocellulose were obtained through acid hydrolysis. The properties of the different nanobiocomposites were comparatively evaluated, including their barrier and mechanical properties. The nanocrystals obtained for coconut shell (CS), corn husk (CH), and corncob (CC) presented a length / diameter ratio of 40.18, 40.86, and 32.19, respectively. Wheat bran (WB) was not considered an interesting source of nanocrystals, which may be justified due to the low percentage of cellulose. Significant differences were observed in the properties of the films studied. The water activity varied from 0.601 (WB Film) to 0.658 (CH Film) and the moisture content from 15.13 (CS Film) to 20.86 (WB Film). The highest values for tensile strength were presented for CC (11.43 MPa) and CS (11.38 MPa) films, and this propriety was significantly increased by nanocellulose addition. The results showed that the source of the nanocrystal determined the properties of the chitosan/glycerol films.

There are several fruits native to cultivated in Brazil that have not been studied for their antioxidant potential and functional characteristics. This study characterized the physico-chemical composition, mineral and levels of compounds of the pulp and peel of ten fruits. The evaluated fruits were atemoya, ambarella, breadfruit, soursop, jackfruit, lychee, mangaba, sapodilla, hog plum, and sugar apple. Higher protein content was observed (from 1.24 to 3.43g/100 g) in the peel and the pulp in fruits of the Annonaceae family (atemoya, cherimoya and sugar apple), and the sapodilla showed higher lipid content (2.37 and 3.37g/100g, for pulp and peel respectively). In general, concentration of minerals was higher in the peel than in the pulp. The fruits of the Annonacea family had the highest total phenolic values mainly in the peel. The highest anthocyanin and flavonoids content was found in the peel of lychee, and in the mangaba peel, respectively. Most fruits had higher concentration of the investigated analytes (physicalchemicals, minerals and phytochemicals) in the peels (considered waste from agricultural industries) against their respective pulps.

The optimized extraction process of natural matrices such as propolis that results in extracts with significant compounds has been one of the main needs of the industry. The aim of this work was to analyze the content of the active components of Brazilian red propolis extracts previously treated with ultrasound, as well as to evaluate in vitro their performance regarding antioxidant capacity and against bacteria and tumor cells. The results of the chromatographic analysis showed the influence of ultrasound treatment for higher yields of formononetin and kaempferol. However, just a higher content of these two components was not enough to interfere with higher concentrations of phenolic compounds and flavonoids among the extracts. The ten extracts obtained showed activity against two bacterial strains, and eight of them showed >70% cytotoxicity against five neoplastic cell lines. These results demonstrated the influence of ultrasound technology as a pretreatment in obtaining the ethanolic extracts of propolis, increasing the possibility of the applicability of Brazilian red propolis in different areas.