Antioxidant and Anti-tyrosinase Activities of Phenolic Extracts from Rape Bee Pollen and Inhibitory Melanogenesis by cAMP/MITF/TYR Pathway in B16 Mouse Melanoma Cells

Abstract

Rape bee pollen possesses many nutritional and therapeutic properties because of its abundant nutrimental and bioactive components. In this study, free (FPE) and bound (BPE) phenolic extracts of rape bee pollen were obtained, phenolic and flavonoid contents were determined, and composition of phenolic acids was analyzed. In vitro antioxidant and anti-tyrosinase (TYR) activities of FPE and BPE were compared, and inhibitory melanogenesis of FPE was further evaluated. Results showed FPE and BPE contain total phenolic contents of 11.76 and 0.81 mg gallic acid equivalents/g dry weight (DW) and total flavonoid contents of 19.24 and 3.65 mg rutin equivalents/g DW, respectively. Phenolic profiling showed FPE and BPE fractions contained 12 and 9 phenolic acids, respectively. FPE contained the highest rutin content of 774.87 μg/g. FPE and BPE showed the high antioxidant properties in vitro and high inhibitory activities for mushroom TYR. Higher activities of FPE than those of BPE can be attributed to difference in their phenolic compositions. Inhibitory melanogenesis activities of FPE against B16 were further evaluated. Results showed suppressed intracellular TYR activity, reduced melanin content, and promoted glutathione synthesis (p < 0.05) in FPE-treated cells. FPE reduced mRNA expression of TYR, TYR-related protein (TRP)-1 and TRP-2, and significantly suppressed cyclic adenosine monophosphate (cAMP) levels through down-regulation of melanocortin 1 receptor gene expression (p < 0.05). FPE reduced mRNA expression of microphthalmia-associated transcription factor (MITF), significantly inhibiting intracellular melanin synthesis (p < 0.05). Hence, FPE regulates melanogenesis of B16 cells involved in cAMP/MITF/TYR pathway. These results revealed that FPE can be used as pharmaceutical agents and cosmetics to protect cells from abnormal melanogenesis.

Bee pollen as a natural antioxidant source to prevent lipid oxidation in black pudding

“…Concerning the values obtained for reducing power assay, they are also higher than those reported for Rape Bee Pollen (Sun, Guo, Zhang, & Zhuang, 2017).…”

UHPLC‐ESI‐QTOF‐MS phenolic profiling and antioxidant capacity of bee pollen from different botanical origin

“…In particular, Gabriele and co‐authors (Gabriele et al ., ) reported TPC values of 24.8, 21.1 and 13.5 (mg GAE g −1 ) considering three botanical genera namely Castanea , Cistus and Rubus , respectively, whilst Pascoal and co‐authors (Pascoal et al ., ) reported an average TPC of 26.0 mg GAE g −1 considering eight commercial bee pollen samples belonging to Cistaceae, Fabaceae, Ericaceae, Boraginaceae floral families from different countries. Concerning the in vitro antioxidant capacity values, present ORAC values were very close to those reported by Gabriele and co‐authors (Gabriele et al ., ) (on average 534.3 μmol TE g −1 ), whilst ABTS and DPPH values were difficult to compare with literature mainly due to different units of measure adopted (Pascoal et al ., ; Gabriele et al ., ; Sun et al ., ). Moreover, the determination of the antioxidant capacity is strongly influenced by the experimental conditions and heterogeneity of matrix, so this could complicate also the comparison between the results (Sakanaka & Ishihara, ).…”

Anti-Diabetic Effects of Phenolic Extract from Rambutan Peels (Nephelium lappaceum) in High-Fat Diet and Streptozotocin-Induced Diabetic Mice

“…Phenolic compounds are important secondary plant metabolites that determine the sensory and nutritional qualities of fruits, vegetables, and other plant products. Phenolics have received attention in recent years because of their antioxidant [5], antimicrobial [6], antimelanogenesis [7], hepatoprotective [8] and anti-inflammatory [9] effects. Studies suggest that a large number of phenolic extracts from plants, including mulberry leaf [10], Pistachia lentiscus L. leaves from Algeria [11], Astilboides tabularis [12], mate tea [13], Korean sorghum [14], Pongamia pinnata Pierreseeds [15], and Pseuduvaria monticola bark [16], demonstrate anti-diabetic properties.…”