Honey is used for its nutritional and functional properties. The Argentinean Northwest is a region with a growing potential for honey production, but up to now, few physicochemical and biological studies have been carried out. The aim of this study is to characterize monofloral (Prosopis sp and Citrus lemon) and multifloral honey samples from the Argentinean Northwest from a physicochemical and functional standpoint. The results showed that the honeys had good properties of stability and freshness. The highest content of flavonoid and phenolic compounds correspond to multifloral honeys. A positive correlation was observed between colour intensity and flavonoid or phenolic compounds content (R2 = 0.98 and R2 = 0.92, respectively). The flavonoids, chrysin and pinocembrin were present in all samples analyzed, while hesperidin and hesperetin were numerically more important in lemon honey (>1 mg/kg), providing a valuable marker of botanical origin.

Varroa destructor is an ectoparasitic mite that affects colonies of honey bee Apis mellifera worldwide. In the last years, substances of botanical origin have emerged as natural alternative acaricides to diminish the population levels of the mite. In the present work, the bioactivity of propolis from different geographical locations of Pampean region from Argentina on V. destructor was evaluated. Fourteen propolis samples were organoleptic and physicochemically characterized and, by means topical applications, their activity was tested on mites. All propolis had a homogeneous composition and the bioactivity levels against mites were comparable among the different propolis samples. The percentage of mites killed by the treatments ranged between 60.5% and 90% after 30 s of exposure. Thus, V. destructor was highly susceptible to propolis. Moreover, the mites remained anesthetized during the first hours after topical treatment. The results suggest that propolis from Argentinean pampas could be incorporated in honey bee colonies as acaricidal treatment by spraying.

Propolis was included in the Argentine Food Code as a functional food. The chemical parameters and antioxidant properties of propolis samples from the same colonies of Apis mellifera in San Juan (Cuyo region, Western Argentine) were compared every month for 1 year using two collection methods. Chemical parameters were analyzed by the spectrophotometric method and fingerprinting using high-performance liquid chromatography with ultraviolet detection. The antioxidant activities of propolis samples were measured using model systems including the analysis of the scavenging activities for 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and the beta-carotene bleaching assay. The results showed that propolis had a higher free radical scavenging and lipid peroxidation inhibitory capacity than butylated hydroxytoluene and quercetin, antioxidants used in the pharmaceutical and food industries. The concentration required to scavenge 50% of free radicals (SC(50)) values differed depending on the sample collection month. Samples collected in November had the highest antioxidant capacity. In all cases, SC(50) values of propolis samples obtained by scraping were similar to those collected from a wire mesh (5 microg/mL for ABTS and 20-30 microg/mL for DPPH radicals). A significant positive correlation was found between the antioxidant capacity and flavonoid content of each analyzed extract. The chemical profiles were very similar. Galangin (3,5,7-trihydroxyflavone), an antioxidant compound, was detected in all samples as a major compound. The chromatographic profile suggests that of Baccharis sp., which would be one of the botanical sources of propolis from western Argentina, and the content of galangin can be used as a parameter for evaluating propolis quality. Our results suggest that Argentine propolis from Cuyo is a promising source of bioactive compounds as ingredients for developing functional foods with a beneficial impact on oxidative stress.

Preliminary studies have determined the excellent quality of Argentine Propolis. However, the big diversity between them makes necessary to characterize and to standardize these propolis. The objective of this work is to determine the physico-chemical composition of the propolis wich are obtained in different zones to make the standards. A trial, carried out by the PROAPI's promoters' net, was done taking 30 places from 22o to 52o SL for sampling. A complete aleatory design with three levels of treatment (method of crop) and 10 repetitions was use in each place: moisture, waxes, resins, mechanical mixtures, ashes, and total phenolic compounds, were determinated in each samples. The results are in the ranks described by other autors, but they show a high variability between different regions. This increases the need to advance in standardization. The results are discussed in the paper. This work is financed by the National Agency of Scientific and Technological Promotion and beekepers contribute with 900 hives for sampling.

The flavonoids are considered the main bioactive components of propolis at the moment. These compounds have important antioxidant properties, because of they decrease lipidic peroxidation and the effects of free radicals, contributing to reduce risk of cardiovascular illnesses. It is known that Apis mellifera collects resins of diverse plants, and therefore, chemical composition of propolis will vary according to the flora of each region. As a part of the project “Physiquechemical characterization of Argentinean Propolis and their extracts”, this work was carried out in order to evaluate the content of these compounds in the Argentinean Propolis from different regions. 84 propolis samples from the following regions were analyzed: Chaquean Park, Calchaqui Valley, Cuyo, Pampean Steppe and North Patagonia. It was determined the total flavonoids content and the UV spectrum.