Examination the antioxidant potentials and antidiabetic properties of phenolic extracts of some Iranian honeys

Abstract

Introduction: In most ancient cultures, honey has been used for both nutritional and medical purposes. Objectives: In this research, phenolic extracts of four Iranian honeys were evaluated to determine the antioxidant potentials using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, nitric oxide (NO) radical scavenging and reducing power by ferric reducing activity of plasma (FRAP) method. Additionally, anti-diabetic properties of honey and phenolic extracts were evaluated by determination of α-amylase and α-glucosidase inhibition. Patients and Methods: Besides, reducing potential was evaluated by ferric-reducing antioxidant power method. Moreover, determination of phenolic and flavonoid contents was performed. Moreover, inhibition of α-amylase and α-glucosidase of honey and phenolic extracts were evaluated. Results: With considering to antioxidant potentials, Gavan (Astragalus) sample showed the greatest phenolic (3817±1.52 mg GAE/100 g), flavonoid contents (3.1±0.005 mg QE/100 g), and DPPH radical scavenging (IC50 = 2±0.003 mg/mL). Bahareh honey had the highest NO radical scavenging (IC50=0.0403±0.0009 mg/mL) and Meymand honey possessed the highest reducing potential by FRAP method (IC50=0.0018±0.000003 mg/mL). The maximum inhibition of α-glucosidase was shown in Meymand honey extract (46±0.1%). After sugar isolation, Zataria honey had the highest inhibition of α-glucosidase (54±0.6%) and the mode of α-amylase inhibition was noncompetitive by this honey. Whole extract (23±0.1%) and phenolic extract of Gavan honey presented the maximum inhibition of α-amylase (31.2±0.1%). Conclusion: Honey samples showed antioxidant potentials and anti-diabetic properties by retardation of α-amylase and α-glucosidase.

Keywords

• antioxidant activity
• α-amylase inhibition
• α-glucosidase inhibition
• iranian honey
• radical scavenging