Caracterização química, atividade antioxidante e antimicrobiana do óleo essencial de Baccharis oreophila Malme

The Baccharis oreophila Malme belongs to the Asteraceae family. In Brazil are reported 120 species of Baccharis, most located in the South and Southeast regions, the latter presents the highest prevalence, especially in the state of São Paulo. Asteraceae is well known for the production of essential oils, which are liquid, volatile and aromatic substances produced by plants specialized for metabolism possess antibacterial, antifungal, and antioxidant properties. Thus, this study aimed, perform chemical and evaluate the antimicrobial and antioxidant activity of essential oil from dried leaves of B. oreophila collected in winter in Piraquara, Paraná. Obtaining essential oil was given by hydrodistillation in Clevenger apparatus, in triplicate, and the analysis was done using a gas chromatograph coupled to mass spectrometry GC / MS. The identification of the components was made based on retention indices calculated from the co-injection of a series of n-alkanes, followed by comparison of their mass spectra with literature. The antimicrobial activity was assessed by disk diffusion method and microdilution. The antioxidant activity was evaluated by the methods DPPH equivalent Trolox, ABTS and FRAP equivalent Trolox equivalent ferrous sulfate. The essential oil showed 0.47% yield. They identified 57 components (89.38%), 1.51% were classified as hydrogenated monoterpenes, oxygenated monoterpenes 15.14%, 34.84% and 37.87% hydrogenated sesquiterpenes sesquiterpenes oxygenates. As the major components were detected kusimono (16.37%), spathulenol (16.12%), the δ-cadinene (5.68%) and bicyclogermacrene (4.09%). The antimicrobial activity of essential oil was performed for the microorganisms Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Candida albicans ATCC 18804 and Candida tropicalis ATCC 13803, the results showed that the essential oil showed activity against S. aureus Inhibitory Concentration minimum (CIM) 1250 g/mL. In the evaluation of antioxidant activity essential oil showed antioxidant potential for the three methods evaluated, with values of 1,468 m.mol.L-1, 7.126 m.mol.L-1 and 45.515 m.mol.L-1 for ABTS, DPPH and FRAP, respectively. These results demonstrate that the essential oil of B. oreophila showed antimicrobial potential against S. aureus and interesting antioxidant activity, especially for the reducing power of iron ion, demonstrating their potential for future industrial applications. It is important to emphasize that were not observed in the literature reports highlighting such biological properties of B. oreophila oil.

Melhoria da qualidade de jerked beef pela substituição de nitrito de sódio por extratos naturais de própolis e erva mate como agente antioxidante

Jerked beef, an industrial meat product obtained from beef with the addition of sodium chloride and curing salts and subjected to a maturing and drying process is a typical Brazilian product which has been gradually discovered by the consumer. The replacement of synthetic antioxidants by natural substances with antioxidant potential due to possible side effects discovered by lab tests, consumer health, is being implemented by the meat industry. This study aimed to evaluate the lipid oxidation of jerked beef throughout the storage period by replacing the sodium nitrite by natural extracts of propolis and Yerba Mate. For jerked beef processing brisket was used as raw material processed in 6 different formulations: formulation 1 (control - in nature), formulation 2 (sodium nitrite - NO), formulation 3 (Yerba Mate - EM), formulation 4 (propolis extract - PRO), formulation 5 (sodium nitrite + Yerba Mate - MS + NO), formulation 6 (propolis extract + sodium nitrite - PRO + NO). The raw material was subjected to wet salting, dry salting (tombos), drying at 25°C, packaging and storage in BOD 25°C. Samples of each formulation were taken every 7 days for analysis of lipid oxidation by the TBARS method. In all formulations, were carried out analysis of chemical composition at time zero and sixty days of storage. The water activity analysis and color (L *, a *, b *) was monitored at time zero, thirty and sixty days of storage. The Salmonella spp count, Coliform bacteria, Termotolerant coliforms and coagulase positive staphylococci were taken at time zero and sixty days. The activity of natural antioxidants evaluated shows the decline of lipid oxidation up to 2.5 times compared with the product in natura and presented values with no significant differences between treatments NO and EM, confirming the potential in minimize lipid oxidation of Jerked beef throughout the 60 days of storage. The results also showed that yerba mate has a higher antioxidant capacity compared to the propolis except the PRO + NO formulation. When associated with yerba mate with sodium nitrate, TBARS values become close to values obtained only for the control samples with the addition of sodium nitrite. The proximal composition of the formulations remained within the standards required in the IN nº22/2000 for jerked beef. Samples that differ significantly at 5% are directly related to the established type of formulation. The count of microorganisms was within the standards of the DRC nº12/2001 required for matured meat products. The intensity of the red (a*) decreased with storage time and increase the intensity of yellow (b*) indicates a darkening of the product despite L* also have been increased. These results suggest that yerba mate is a good alternative to meat industry in reducing healing addition salts when associated with another antioxidant.