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.

Two Gram-stain-positive, moderately thermophilic, endospore-forming, rod-shaped, motile bacteria designated PDF4T and PDF10, were isolated from Camkoy hot spring in the provinces of Aydın, Turkey and were characterized in order to determine their phylogenetic position. 16S rRNA gene sequence analysis revealed that the two strains belonged to the genus Brevibacillus. Strain PDF4T showed highest 16S rRNA gene sequence similarity to strain PDF10 (99.5 %), Brevibacillus brevis DSM 30T (98.9 %), Brevibacillus parabrevis DSM 8376T (98.6 %) and Brevibacillus formosus DSM 9885T (98.5 %); similarities to other species of the genus Brevibacillus were less than 98.5 %. The predominant fatty acids of strain PDF4T were anteiso-C15 : 0 (60.0 %) and iso-C15 : 0 (22.3 %). The polar lipids of strain PDF4T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, an unknown phospholipid, two unknown lipid, an unknown aminophospholipid and two unknown aminolipids. MK-7 was detected as a sole respiratory quinone, and the cell wall of strain PDF4T contained meso-diaminopimelic acid. The DNA G+C content of strain PDF4T was 51.7 mol%. DNA–DNA hybridization showed less than 60 % relatedness between strain PDF4T and type strains of the most closely related species given above. Based on these data, the two strains are considered to represent a novel species of the genus Brevibacillus, for which the name Brevibacillus gelatini sp. nov. is proposed. The type strain is PDF4T ( = NCCB 100559T = DSM 100115T).