Antimicrobial Activity and Protective Effect of Tuscan Bee Pollens on Oxidative and Endoplasmic Reticulum Stress in Different Cell-Based Models

• Main Authors: Morena Gabriele, Stefania Frassinetti, Laura Pucci
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Foods
• Subjects: bee pollen; antioxidant activity; antihemolytic effect; Cellular Antioxidant Activity in Red Blood Cells CAA-RBC; antimicrobial activity; Minimum Inhibitory Concentration (MIC)
• Online Access: https://www.mdpi.com/2304-8158/10/6/1422

Bee pollen is an apiary product of great interest owing to its high nutritional and therapeutic properties. This study aimed to assess the cellular antioxidant activity and the antihemolytic effect of <i>Castanea</i>, <i>Rubus</i>, and <i>Cistus</i> bee pollens on human erythrocytes. We also tested the antimicrobial potential of each sample on selected Gram-negative and Gram-positive bacteria. Finally, the effect of <i>Castanea</i> bee pollen, showing the best phytochemical profile, was analyzed on human microvascular endothelial cells exposed to thapsigargin, used as endoplasmic reticulum (ER) stressor. Our results showed good biological activities of all bee pollen samples that, under oxidative conditions, significantly improved the erythrocytes’ antioxidant activity and limited cell lyses. <i>Castanea</i> and <i>Cistus</i> showed comparable antihemolytic activities, with higher % hemolysis inhibition than <i>Rubus</i>. All samples exerted antimicrobial activity with different selectivity among all the tested microorganisms with minimal inhibitory concentration values ranging from 5 to 10 mg/mL. Finally, <i>Castanea</i> bee pollen was effective in reducing gene over-expression and oxidation process arising from thapsigargin treatment, with a maximum protective effect at 10 µg/mL. In conclusion, bee pollen represents a potential natural antibacterial and a good nutraceutical product useful in the prevention of free radical and ER stress-associated diseases.