Phytochemical analysis and antibacterial potential of Onosma hispidium and Alcea rosea

Introduction and Aim:  Medicinal plants are widely used in traditional medicine to cure various infectious diseases in human. The medicinal herbs like Onosma hispidium and Alcea rosea have been traditionally used for the variety of clinical disorders like jaundice, Diabetes, malaria, rheumatism and have been used as laxative, anthelmintic, disorder of blood, disease of eyes, bronchitis, abdominal pain, antibacterial and as wound healer. The present study was undertaken to investigate the antibacterial potential of aqueous, ethyl acetate and methanolic extracts of Onosma hispidium and Alcea rosea, a traditionally used medicinal plants with multiple therapeutic properties. Materials and Methods: The susceptibility of microbial strains to the plant extracts was determined using agar well diffusion method. The bacterial strains employed were Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris and Escherichia coli. Phytochemical screening was performed using standard methods. Results: A dose dependent increase in the antibacterial activity was observed with both the methanol, ethyl acetate and aqueous extracts. Among the plants screened, in Onosma hispidium the highest antibacterial activity was exhibited by aqueous extract with Pseudomonas aeruginosa (25±1.88) followed by Staphylococcus aureus (22 ± 0.22 mm) and Klebsiella pneumoniae (20.21±1.01) at the concentration of 100 mg/ml respectively. while in case of  Alcea rosea, the ethyl acetate extract exhibited the highest antibacterial activity with Escherichia coli (28±1.56) followed by Staphylococcus aureus (25 ± 01.58 mm) Klebsiella pneumoniae (18±0.74) and Proteus vulgaris (13±0.12) at the concentration of 100 mg/ml respectively. Phytochemical analysis revealed the plants are rich in various secondary metabolites like alkaloids, saponins, flavonoids, phenols, terpenoids and volatile oils. Conclusion: The plants contain novel compounds with broad spectrum antibacterial properties. The isolation and characterization of these novel compounds could lead to the development of effective therapeutic antimicrobials to fight pathogenic infections.