The objective of this work was to evaluate the antioxidant properties of Lavandula latifolia waste obtained after essential oil distillation. Samples of 12 wild populations of the Lavandula genus collected between 2009 and 2010 were hydrodistilled and their by-products were analyzed using the Folin-Ciocalteu, free radical scavenging activity (2,2-diphenyl-1-picrylhydrazyl), and the ferric reducing antioxidant power (FRAP) methods. Rosmarinic acid, apigenin, and luteolin contents were analyzed by high-performance liquid chromatography-diode array detection. The mean of total phenolic content ranged from 1.89 ± 0.09 mg gallic acid equivalents/g dry weight to 3.54 ± 0.22 mg gallic acid equivalents/g dry weight. The average value of the half maximal effective concentration (EC50) for scavenging activity ranged from 5.09 ± 0.17 mg/mL to 14.30 ± 1.90 mg/mL and the variability of the EC50 in FRAP ranged from 3.72 ± 0.12 mg/mL to 18.55 ± 0.77 mg/mL. Annual variation was found among this samples and the environmental conditions of 2009 were found to be more favorable. The plants collected from Sedano showed the highest antioxidant power. Our results show that rosmarinic acid and apigenin in L. latifolia contributed to the antioxidant properties of the waste. In conclusion, the by-product of the distillation industry could be valorizing as a source of natural antioxidants.

We analyzed pollen from 89 honey samples, collected in León and Palencia provinces (NW Spain). According to their pollen spectra, 46 were considered monofloral. The most abundant monofloral honeys were Erica types followed by Castanea, Centaurea, Reseda and Helianthus. One hundred and forty-two different pollen types were recorded, belonging to 47 families. Fifty-five of them reached percentages over 3% in at least one sample, while the other 87 types never exceeded 3% in any of the 89 samples. The families that were present in the highest number of samples were Fabaceae, Rosaceae, Cistaceae and Asteraceae. Plant families that had the highest percentages were Fabaceae, Ericaceae, Asteraceae, and Rosaceae. The pollen types that appeared in most samples were Rubus ulmifolius (73 samples), Cytisus scoparius (70) and Mentha aquatica (62); the pollen types that had the highest relative abundance were Erica arborea, Lotus corniculatus, Cytisus scoparius. The pollen types of the Ericaceae family, Jasione montana, and Lavandula latifolia types could be used as indicators of the origin of honeys among five zones in the area studied. The use of cluster and correlation statistical analyses proved useful in characterizing honey samples from a geographical and botanical point of view. The honey samples were divided into four classes according to the data matrix of presence/absence, and into seven classes according to absolute frequencies of pollen types in the samples. Key words: Honey, palynology, melissopalynology, botanical origin, characterization