Resveratrol is an antioxidant abundant in red fruits, and one of the most powerful inhibiting reactive oxygen species (ROS) and oxidative stress (OS) produced by human metabolism. The effect of the spray drying processing conditions of blueberry juice (BJ) and maltodextrin (MX) mixtures was studied on content and retention of resveratrol. Quantitatively, analysis of variance (ANOVA) showed that concentration of MX was the main variable influencing content of resveratrol. Response surface plots (RSP) confirmed the application limits of maltodextrins based on their molecular weight, where low molecular weight MXs showed a better performance as carrying agents. After qualitatively comparing results for resveratrol against those reported for a larger antioxidant molecule (quercetin 3-D-galactoside), it was observed a higher influence of the number of active sites available for the chemical interactions, instead of stearic hindrance effects.

The aim of this work was to isolate oil‐degrading bacteria that use chitin or keratin as carbon sources from oil contaminated soils; and additionally to study if oil removal by these bacteria is enhanced when a chitinous or a keratinous waste is added to the culture media. To isolate the above‐mentioned bacteria, 12 soil samples were collected close to an oil‐well. Such soils showed unsuitable nutrients content, but their counts of heterotrophic bacteria ranged within 10⁵–10⁸ CFU g⁻¹ soil, of which 0.1–77% corresponded to oil hydrocarbon‐degrading ones. By sampling on plates, 109 oil‐degrading bacterial isolates were obtained. Their keratinase and chitinase activities were then screened by plate assays and spectrophotometric methods, resulting in 13 isolates that were used to integrate two mixed cultures, one keratinolytic and the other chitinolytic. These mixed cultures were grown in media with oil, or oil supplemented with chicken‐feathers or shrimp wastes. The oil‐hydrocarbon removal was measured by gas chromatography. Results showed that keratinolytic bacteria were better enzyme producers than the chitinolytic ones, and that oil removal in the presence of chicken‐feathers was 3.8 times greater than with shrimp wastes, and almost twice, in comparison with oil‐only added cultures. Identification of microorganisms from the mixed cultures by 16S rDNA, indicated the presence of seven different bacterial genera; Stenotrophomonas, Pseudomonas, Brevibacillus, Bacillus, Micrococcus, Lysobacter and Nocardiodes. These findings suggest that the isolated microorganisms and the chicken‐feather wastes could be applied to the cleaning of oil‐contaminated environments, whether in soil or water.