Antibacterial Activity of Different Extracts of Aerial Parts of Chondrilla juncea L, Ajuga comata Stapf, Nepeta ucrainica L, and Delphinium speciosum M.B

Background and purpose: Herbal drug derivatives have been commonly used in management and treatment and of some infections.  This study aimed at evaluating the antibacterial effects of Chondrilla juncea L, Ajuga comata Stapf, Nepeta ucrainica L, and Delphinium speciosum M.B extracts. Materials and methods: Antibacterial activity of different extracts (n-hexane, dichloromethane, and methanol) of the aerial parts of Chondrilla juncea L, Ajuga comata Stapf, Nepeta ucrainica L, and Delphinium speciosum M.B were assessed against gram positive, gram negative and fungi strains using agar diffusion method. Potent extracts were subjected to fractionation using Vacuum Liquid Chromatography (VLC). Minimum Inhibitory Concentration (MIC) values of all samples were also investigated. Results: Staphylococus aureus and Bacillus subtilis were found to be the most sensitive bacteria. In agar diffusion assays, the n-hexane extract of D.speciosum and dichloromethane extract of C.juncea were the most active extracts against  S. aureus (35 and 30mm, respectively) and B. subtilis (30 and 20mm, respectively). Other extracts showed no anti-microbial activity against different bacteria. In current study, 10 and 20% VLC fractions of n-hexane extract of D. speciosum exhibited stronger antibacterial activity against S. aureus and B. subtilis. MIC of both potent fractions were 500µg/ml and 250µg/ml against S. ureus and B. subtilis, respectively. Conclusion: Among the plant extracts studied, n-hexane extracts and 10 and 20% VLC fractions of the n-hexane extract of Delphinium speciosum showed higher antimicrobial effects.