Investigation of the antimicrobial activities of solvent extracts of two endemic species from Turkey: Campanula tomentosa Lam. and Verbascum mykales Bornm.

Abstract

Background and Aims: Campanula tomentosa Lam. and Verbascum mykales Bornm. are endemic species in Turkey. Extracts of these plants contain important natural compounds such as flavonoids, saponins and tannins. This study investigates the antimicrobial effects of leaf extracts of C. tomentosa and V. mykales against some bacteria and yeasts. Materials and Methods:Leaves of plant samples were air-dried and ground into powder. Five solvents (ethyl acetate, methanol, acetone, chloroform, boiled water) were used for extraction. Experiments were conducted using these crude extracts on seventeen bacteria, three yeasts and three microfungi. The agar well diffusion method was used for the antimicrobial activities of the extracts. In addition, minimum inhibitory concentrations, minimum bacteriocidal concentration, minimal fungicidal concentrations were carried out. Results:The ethyl acetate and methanol extracts of C. tomentosa and V. mykales were found to be highly effective against the tested microorganisms. According to the MIC values, the ethyl acetate extracts of C. tomentosa and V. mykales had a strong effect (4-8 μg/mL) against Escherichia coli ATCC 35218, Micrococcus luteus ATCC 9341, Streptococcus pneumonia ATCC 27336, Pseudomonas aeruginosa ATCC 35032, Mycobacterium smegmatis ATCC 607, Proteus vulgaris ATCC 33420, Enterococcus faecalis ATCC 29212, Bacillus cereus ATCC 11778, and Bacillus subtilis ATCC 6633. The ethyl acetate extract of C. tomentosa had a moderate effect (64 μg/mL) against Candida albicans ATCC 10231 and Saccharomyces cerevisiae ATCC 9763, and the ethyl acetate extract of V. mykales had a moderate effect (64 μg/mL) against Aspergillus flavus ATCC 9807 and Aspergillus niger ATCC 16404. However, the boiled water extract of C. tomentosa and V. mykales had no effect on the tested microorganisms. Conclusion:C. tomentosa and V. mykales used in the study are endemic plants and their antimicrobial activities are being investigated for the first time. The ethyl acetate extract of both plants was found to be most effective against the Gram (+) and Gram (-) bacteria. However, all extracts of both plants were found to have fewer antimicrobial effects against used yeasts and microfungi. This study demonstrates that plant extracts are more effective against prokaryotic microorganisms than eukaryotes.

Biofilm Formation and Prevention of Bacteria Isolated from Fish and Fish Stalls

“…Colony selection was made at the end of the incubation and the purification process was applied. Pure cultures were taken in 20% Skim Milk and stored at -20 o C (Törün et al, 2017;Tekin and Çoban, 2021;Çoban and Barışık, 2021).…”