Influence of Brassica campestris and Galega officinalis on Antioxidant Activity of Bee Pollen

The presence of polyphenol compounds in bee pollen differs with the floral species that comprise the pollen. These polyphenols are thus responsible for the free radical scavenging ability that the pollen exhibits. To correlate the botanical origin with the polyphenol content of Chilean bee pollen, samples were extracted in methanol using ultrasound-assisted extraction. Total polyphenol content, total flavonoid content, and antioxidant capacity were determined in all samples along with the polyphenol HPLC profile. According to the melissopalynological analysis, samples were either monofloral or multifloral bee pollen, with total polyphenol content between 7.7 and 22 mg eq gallic acid/g of bee pollen and total flavonoid content between 76 and 296 mg quercetin/kg pollen. All extracts showed an antioxidative activity for the ABTS radical of 23.9 to 43 mg eq trolox/g of bee pollen, and lower values for DPPH scavenging capacity (0.98 to 4.74 mg eq trolox/g of bee pollen). Coumaric acid and caffeic acid were present in all bee pollen, but different polyphenol profiles were observed among the samples. Results show a high correlation between the properties exhibited and the relative amount of pollen from Brassica campestris and Galega officinalis in the sample, indicating a dependence of the bioactivity of bee pollen with the botanical origin and chemical composition.