Black thyme (Thymus vulgaris), white thyme (Thymus serpyllum) and lemon (Thymus citriodorus): Antioxidant and Antimicrobial Effects

Abstract

Thyme plants have many different health-beneficial properties, including antimicrobial, antioxidant, anti-inflammatory, cardioprotective, neuroprotective, anticarcinogenic and hypoglycemic activities. In this study, the antimicrobial and antioxidant properties of three different thyme extracts: black thyme (Thymus vulgaris), white thyme (Thymus serpyllum) and lemon (Thymus citriodorus) were determined. The antioxidant properties of different thyme species extracts were examined using 2,2′-azino-bis-3- ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picryl-hydrazyl (DPPH) methods, while total phenolic compounds Folin- It was examined using the Ciocalteu method. Accordingly, the highest amount of TPC was determined in the Thymus citriodorus species as 4306.45 mg GA/g. Total phenolic concentrations were found to vary between 3606.32 and 4306.45 mg GAE / kg, ABTS values between 247.30 and 286.36 mmol Trolox / g, and DPPH inhibition percentage between 97.99% and 78.54%. The DPPH inhibition of black thymus (Thymus vulgaris) had higher DPPH inhibitions (97.99 5) than white thymus and lemon thymus respectly (86 % and 78%). The antimicrobial effect of these thyme extracts against Escherichia coli, Enterococcus faecalis, Bacillus cereus, Pseudomonas aeruginosa and Salmonella typhimurium was determined by the agar diffusion method. Thyme extracts showed different levels of antimicrobial activity against the tested microorganisms. The methanol extract of black thyme (Thymus vulgaris) showed the highest inhibitory activity (18 mm) against Salmonella typhimurium. All the tested thyme extracts exhibited considerable magnitude of antibacterial activity against the tested panel of microorganisms.