Chemical constituents, antioxidant, and anticancer activities of bee pollen from various floral sources in Taiwan

Bee pollen has been traditionally used for health promotion. However, the chemical constituents and pharmaceutical effects of bee pollen strongly depend on their sources. This study determined chemical compositions and evaluated the antioxidant and anticancer activity of six bee pollen samples from Taiwan. The Cs sample contained the highest amounts of carotenoid (417.67 mg/g DW) and anthocyanin (10.96 μmol/g DW) while the Nn sample showed the highest content of chlorophyll (Chl) a (23.39 mg/g DW) and Chl b (39.17 mg/g DW). The highest flavonoid (11.69 mg QE/g DW) and phenolic content (42.91 mg GAE/g DW) were found in Bp and Pm samples, respectively. The highest Fe2+-chelating ability was observed in Bp (IC50 value of 6.28 mg/mL), while Bn exhibited the most effective in scavenging DPPH radical with IC50 value of 3.96 mg/mL. The Bp sample also showed the highest activity against three breast cancer cell lines, MCF-7 (cell viability of 43.5%), BT-20 (cell viability of 0%), and Hs 578T (cell viability of 0%). This study suggested that the level of bioactive compounds and biological activity of bee pollen significantly differ among their sources and the Bp is a potent antioxidant and anticancer agent for medicinal use.