Antibacterial Potential of Clonally Propagated Prunella vulgaris L. under in vitro Conditions

Aims: The study aims to determine the antibacterial efficacy of Prunella vulgaris plant produced by micropropagation method.

Place and Duration of Study: The study was carried out during May and June 2018 at Kütahya Dumlupınar University Biotechnology Laboratory and Manisa Celal Bayar University Microbiology Laboratory.

Methodology: Shoot explants isolated from in-vitro germinated sterile plantlets were cultured in MS medium containing 3 mg/l BAP and 1 mg/l IBA. The plantlets have been subculture for 10 times at an interval of two weeks and harvested. The plantlets were dried in the shade at room temperature for antibacterial activity studies. Ethanol and chloroform extracts from micropropagated plants were assayed against nine bacteria species (Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 25922, Bacillus cereus ATCC 7064, Bacillus subtilis ATCC 6633, Salmonella typhimurium CCM 5445, Proteus vulgaris ATCC 6896, Enterococcus faecalis ATCC 29212, Enterobacter cloacae ATCC 13047, and Kocuria rhizophila ATCC 9341). Penicillin G, novobiocin, ampicillin, chloramphenicol and erythromycin as test antibiotics were used for comparison.

Results: Extracts of P. vulgaris showed 20 to 28 mm inhibition zones against Proteus vulgaris and Salmonella typhimurium. Prunella vulgaris found more effective on gram-positive bacteria in compared to gram-negatives.

Conclusion: Prunella vulgaris found more effective on gram-positive bacteria than gram-negatives. The present investigation clearly indicates that the antibacterial activity varies with the P. vulgaris. Further, the active phytocompounds of this plant against some bacteria should be characterised, and their toxicity should be evaluated in in-vivo.