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Polyphenolic content, flavonoid content, and free flavonoid aglycon compounds were determined in 11 samples of Spanish honeybee-collected pollen. Adequate extraction was obtained with ethyl acetate in the determination of free flavonoid aglycon. Recovery (>83.6%), within-run repeatability (<6.67%), between-run reproducibility (<8.73%), and detection limits (1.4--1.9 mg/kg) were satisfactory. A total of 15 compounds were separated with gradient reversed phase HPLC, and 13 were identified and quantified using diode array detector. The most predominant compounds were flavonoid glycosides, mainly flavonols. Eighty-two percent of the samples contained at least 14 of the phenolic components, primarily rutin, quercetin, myricetin, and trans-cinnamic acid as free aglycons. Total phenols were present, at levels of >0.85 g/100 g in the form of non-tannins, and flavonoids of >0.35 g/100 g, using spectrophotometric procedures. Rutin is the best identifier of free flavonoid aglycon compounds. A minimum quantity of 200 mg/kg of rutin is suggested to guarantee the nutritional and biological properties required in the European market.

The aim of this study was to determine the composition and microbiological quality of honeybeecollected pollen from various botanical and geographical origins of Spain and to define the following physicochemical and microbiological characteristics: water content, water activity (A w ), mean pollen pellet size, protein content, fat content, fatty acid composition, free amino acid distribution, sugar spectrum, mineral elements, dietary fiber, starch content, aflatoxins, and microbiological parameters. The free amino acid spectrum showed a high level of proline (63.1%) of the total free amino acid content (x ) 31.6 ( 4 mg/g). The main sugars identified by gas chromatography were fructose, glucose, and sucrose, with small amounts of di-and trisaccharides. A high level of dietary fiber was detected (x ) 13.7 ( 1.3 g/100 g). The main fatty acids detected corresponded to C 18:2 , C 18:3 , and C 18:1 acids. The mineral elements showed a predominance of potassium, phosphorus, calcium, and magnesium. The pollen of Cistus ladaniferus was detected as the dominant pollen. Among the microbiological parameters, a high number of molds, total aerobic counts, and the presence of coliforms and Streptococci "D" of Lancefield were found. Aflatoxins were not detected.

The composition and bacteriostatic activities of fifteen propolis samples from various botanic and geographic origins were determined. Twenty‐six phenolic components were identified by high‐performance liquid chromatography with array photodiode detector. Acacetin and apigenin were most abundant. Pinocembrin, quercetin, rutin and vanillin were present in lesser quantities. Variance analysis shows significant differences (P≤0.05) in the contents of phenols, flavonoids and active components. The minimum inhibitory concentration of propolis is about 53 times higher than that reported for tetracycline againstBacillus subtilis andStaphylococcus aureus, and about 400 times higher againstEscherichia coli.

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