Levels of phenylpropanoids and iridoids in extracts and infusions of Verbena minutiflora.

Herein we report for the first time the levels of phenylpropanoids and iridoids in extracts and infusions of V. minutiflora consumed in Brazil to treat urinary and infectious disorders. An in house validation study demonstrated good accuracy and precision to determine the bioactive compounds in V. minutiflora by HPLC-DAD. Phenylpropanoids varied in the extracts (leaves 139.70 to 221.20 mg g-1, flowers 106.43 to 227.22 mg g-1, stems 42.18 to 56.48 mg g-1). Verbascoside occurred in higher concentration in extracts of leaves (87.66 - 136.16) mg g-1 and flowers (58.12 - 148.96) mg g-1 than in stems (19.24 - 24.62) mg g-1. Iridoids in extracts were as follows: leaves (46.60 - 54.79) mg g-1, flowers (55.88 - 93.87) mg g-1 and stems (40.05 to 61.74) mg g-1. High levels of iridoids (314.70 - 415.10) µg mL-1, phenylpropanoids (1996.39 - 2674.13) µg mL-1 and verbascoside (1029.38 - 1456.42 µg mL-1) in infusions support the popular consume of V. minutiflora.

A comparison between characterization and biological properties of Brazilian fresh and aged propolis.

OBJECTIVE: As propolis is a highly valued bee product, we aimed to verify the quality of aged propolis, investigating their phenolic and flavonoid composition, levels of toxic metals, radical scavenging and antimicrobial activities. MATERIAL AND METHODS: Samples of fresh and aged propolis of six different beekeepers, from the same geographical location, were investigated in terms of their phenolic and flavonoid composition and levels of Pb, Cd, and Cr, as well as radical scavenging and antimicrobial activities. RESULTS: The two groups of propolis had similar qualitative composition by HPLC-PDA and ESI(-)-MS. Fresh propolis and aged propolis show no differences when average values of extraction yield, flavonoids, EC50, or MIC were compared and both types of propolis showed good antimicrobial activity at low concentrations. Only levels of phenolic compounds were higher in fresh propolis. CONCLUSION: The propolis samples considered in this study, aged or fresh, had similar qualitative composition, although they were collected in different periods. Samples only differed in their levels of total phenolic content. Moreover, aged propolis conserves significant radical scavenging and antimicrobial properties. We suggest that aged propolis should not be discarded but explored for alternative applications.

Propolis as an indicator of environmental contamination by metals.

Concentrations of eleven representative metals (Al, Ca, Cd, Cr, Cu, K, Mg, Mn, Na, Pb and Zn) in forty-two propolis samples were measured by electrothermal atomization and flame atomic absorption spectrometry after calcination in a muffle furnace. Samples were collected from different regions from Paraná State - Brazil where apiculture is an important economic activity. Results showed that the average content of Al, Ca, K, Mg, Mn, Na and Zn in propolis was 0.68, 1.66, 7.59, 1.27, 0.08, 0.58 and 0.02 mg g(-1), respectively. Levels of Al, Ca, and Mg were statistically different in some regions of Paraná and could be used to assign the geographical origin of the propolis. The average concentration of the Cd, Cr, and Pb in raw propolis was 0.13, 5.53 and 9.85 µg g(-1), respectively, and allowed for identification of specific areas with environmental contamination.