Objective: The purpose of this study was therefore to investigate various physicochemical properties, phenolic composition and antioxidant capacities of the oak honey, large quantities of which are produced in the Thrace region of Northwest Turkey. Methods: Hunter color values (Lab), optical rotation, electrical conductivity, moisture and ash were measured as physicochemical determinants. Sugar, proline content, mineral, phenolic acids, total phenolic flavonoids contents were evaluated as chemical parameters. Ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging were used as antioxidant determinants. Results: The results determined that dark-colored honeys (mean 24.95±8.35 L) have proline levels (649.82±203.90 mg/kg), total phenolic content (TPC) (67.29±13.10 mgGAE/100 g) and total flavonoid content (TFC) (10.14±4.78 mgQE/100 g), a high ratio of fructose/glucose (1.65±0.18). Rutin (11.14±8.50 μg/g), p -coumaric acid (6.97±5.80 μg/g) and protocatechuic acid (6.12±4.39 μg/g) were the major phenolic components, and quercetin was also detected in varying amounts in all samples. Potassium (2523±0.28 mg/kg), calcium (63.40±3.20 mg/kg) and magnesium (38.88±0.65 mg/kg) were the major minerals in the honeys. Conclusion: Our results showed that physicochemical properties, phenolic compounds, antioxidant capacity, sugar and mineral contents successfully distinguish the geographical origins of oak honey. These findings will contribute to a more accurate evaluation of oak honey in the literature.

Anzer honey is produced Turkey's famous Anzer Plateau with rich vegetation in the Eastern Black Sea region.This is the first extensive investigation of the bioactive characteristics of Anzer honey. For this purpose, melissopalinological analysis, total phenolic and flavonoid substances, polyphenolic profile and total antioxidant capacity of honey, ferric reducing antioxidant power test (FRAP) and free radical scavenging capacity of samples were measured by picryhydrazil (DPPH) method. According to the results of the study, the total phenolic content of Anzer honey was 26.92 gallic acid/100g and the total flavonoid substance was 2.79. In the analysis of phenolic compounds of the Anzer honeys, daidzein and syringic acid were not detected. The major phenolic compounds in the honey were, in descending order, pinocembrin, hesperidin, chrysin, protocatechuic acid, p-coumaric acid, catechin, caffeic acid phenyl acid (CAPE), p-OH benzoic acid, caffeic acid, and minor levels of myricetin, luteolin, rutin, resveratrol, epicatechin, t-cinnamic acid, ferulic acid and gallic acid, were also determined. The mean FRAP and DPPH values of the anzer honeys were found to be 110.11 μmolTrolox/100g, and 49.12mg/ml respectively. As a result, although Anzer honeys are not rich in phenolic contents, they are attractive in terms of phenolic compounds.

Propolis is a multi-functional bee product rich in polyphenols. In this study, the inhibitory effect of Anatolian propolis against SARS-coronavirus-2 (SARS-CoV-2) was investigated in vitro and in silico. Raw and commercial propolis samples were used, and both samples were found to be rich in caffeic acid, p-coumaric acid, ferulic acid, t-cinnamic acid, hesperetin, chrysin, pinocembrin, and caffeic acid phenethyl ester (CAPE) at HPLC-UV analysis. Ethanolic propolis extracts (EPE) were used in the ELISA screening test against the spike S1 protein (SARS-CoV-2): ACE-2 interaction for in vitro study. The binding energy values of these polyphenols to the SARS-CoV-2 spike and ACE-2 protein were calculated separately with a molecular docking study using the AutoDock 4.2.6 program. In addition, the pharmacokinetics and drug-likeness properties of these eight polyphenols were calculated according to the SwissADME tool. The binding energy value of pinocembrin was highest in both receptors, followed by chrysin, CAPE, and hesperetin. Based on the in silico modeling and ADME (absorption, distribution, metabolism, and excretion) behaviors of the eight polyphenols, the compounds exhibited the potential ability to act effectively as novel drugs. The findings of both studies showed that propolis has a high inhibitory potential against the Covid-19 virus. However, further studies are now needed.

The purpose of this study was to investigate the anti-hyaluronidase activities of honeys from different botanical origins honeys in order to determine their anti-inflammatory properties. The total phenolic contents, total flavonoids and total tannin levels of six types of honey, chestnut, oak, heather, pine, buckwheat and mixed blossom, were determined. Concentration-related inhibition values were tested turbidimetrically on bovine testis hyaluronidase (BTHase) as IC50 (mg/mL). All honeys exhibited various concentration-dependent degrees of inhibition against BTHase. Inhibition values varied significantly depending on honeys' levels of phenolic contents, flavonoid and tannin. The honeys with the highest anti-hyaluronidase activity were oak, chestnut and heather. In conclusion, polyphenol-rich honeys have high anti-hyaluronidase activity, and these honeys have high protective and complementary potential against hyaluronidase-induced anti-inflammatory failures.