Evaluation of Antibacterial Activity and Antioxidant Properties of Methanolic Extracts of Jurinea Sintenisii Bornm and Bupleurium Rotundifolium L

Nowadays, the emergence of allergies, side effects of drugs, antibiotic-resistant strains, and the need of body to antioxidants emphasized the importance of herbal medicines. In the current study, the antibacterial activity and antioxidant properties of methanolic extracts of Jurinea sintenisii Bornm and Bupleurium rotundifolium L., two medical herbs from North Khorasan Province, Iran, were investigated.
Methanolic extracts of the plants were prepared by soaking method and accordingly, their antioxidant activity were assessed by DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and FRAP (Ferric reducing antioxidant power) methods. Also, the antibacterial activity of the extracts were studied on four bacterial species by well-agar-diffusion method.
The IC50 value of Bupleurium rotundifolium L., Jurinea sintenisii Bornm, and butylated hydroxytoluene (BHT) was 0.61, 1.71, and 0.35 mg/mL, respectively, while based on the FARP method, the antioxidant activity of Jurinea sintenisii Bornm and Bupleurium rotundifolium L. were 424.390 and 180.488 mM Fe 2 /g, respectively. In addition, both plants had a good antibacterial activity on Gram-positive bacteria; the minimum inhibitory concentration (MIC) of Jurinea sintenisii Bornm against Bacillus subtilis, Staphylococcus aureus, and Micrococcus luteus was 15.65, 7.81, and 31.25 mg/mL, respectively; while it was 125, 31.25, and 125 for Bupleurium rotundifolium L., respectively.
Bupleurium rotundifolium L. can better inhibit DPPH radicals, while Jurinea sintenisii Bornm can better reduce iron cations; both plants have remarkable antioxidant capacity that can be used in different conditions. In the current study, Jurinea sintenisii Bornm extract had higher antibacterial activities against Staphylococcus aureus (MIC = 7.812 mg/L).