Abstract
Bacteria have evolved numerous defences against antimicrobial agent and drug resistance in pathogen is on rise. This is due to rapid development of multi-drug resistance, limited anti-bacterial spectrum and adverse effects of available anti-microbial agents. This necessitates the search for new antimicrobials with diverse structures and novel mechanism of action. Flowers are mostly used for ornamental purposes and they are not frequently worked out hence marigold flower was selected for the study. The antimicrobial activity of different solvent (Hexane, Toluene, Ethyl acetate, Acetone, Methanol and Aqueous) extracts of marigold flowers were evaluated by agar well diffusion method against a panel of pathogenic microorganisms. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of acetone extract and its fraction were evaluated. B. cereus and K. pneumonia were the most sensitive organisms to acetone extract and minimum inhibitory concentration (MIC) was 78 μg/ml. Synergistic effect of acetone extract and commercial antibiotics (chloroamphenicol and ceftazidime) against pathogenic bacteria was investigated. The best synergistic activity was with combination of acetone extract and ceftazidime against B. subtilis and P. aeruginosa with FIC indices 0.312 and 0.093 respectively. Only the polar solvent acetone extract showed promising antibacterial and synergistic activity. These results indicate that combination between plant extract and the antibiotics could be useful in fighting emerging drug-resistant microorganisms and choice of the solvent plays a prominent role in evaluating antimicrobial activity of medicinal plants. Flowers can be taken as an alternative source of antimicrobial agent against the human pathogens.
Highlights
The progressive emergence of multi-drug resistant bacteria and the infectious diseases caused by them is a major problem
The choice of solvent has a great influence on the extraction yield but it does not imply that the solvent which had maximum yield will show maximum activity under investigation Effect of extraction solvent on antimicrobial and antioxidant activity of medicinal plant extracts is reported by other researchers [27,29]
The results showed that acetone extract of T. erecta flower possessed considerable in vitro antimicrobial activity against many of the microorganisms involved in the pathogenesis of the human infections
Summary
The progressive emergence of multi-drug resistant bacteria and the infectious diseases caused by them is a major problem. Antibiotics sometimes cause side effects on the host like hypersensitivity, immune-suppression and allergic reactions [3]. This burning problem has generated the colossal need to investigate alternative sources of treatment with fewer side effects to combat the activities of these pathogens [4]. Synthetic antimicrobial agents are ineffective against multi-drug resistant bacteria and it is cause the global trouble for the lost of budget use for the treatment infectious diseases. One approach is use of medicinal plants screen for their possible antimicrobial properties which is novel, inexpensive and effective against pathogenic microorganism [5]. Herbal medicine is most popular for treatment of disease because it is available, cheap, less side effects as compared to antibiotic [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
