Abstract
The antibacterial activities of the rosemary, oregano, clove and cinnamon extracts against Listeria monocytogenes, Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were evaluated in agar diffusion test medium and in sterilized milk medium at 37 °C within 24 hr time interval. All tested herbal extracts exhibited an inhibitory effect against pathogens. Gram-negative bacteria E. coli and P. aeruginosa were less susceptible to the inhibitory activity of all herbal extracts used in the experiment as compared to Gram-positive bacteria Staph. aureus, L. monocytogens and B. subtilis in nutrient agar medium as well as in sterilized milk medium. Oregano showed significant effect against all pathogens as compared to clove, cinnamon and rosemary. Whereas, results from rosemary showed significant decrease inmicrobial activity against pathogens as compared to other tested herbal extracts. These results suggest the prospect of using these herbal extracts in milk and milk products as natural antimicrobials. Keywords: Antimicrobial activity; Herbs; Pathogens; Sterilize milk http://dx.doi.org/10.19045/bspab.2021.100041
Highlights
D Pseudomonas aeruginosa were evaluated in agar diffusion test medium and in sterilized milk medium at 37 °C within 24 hr time interval
Antimicrobial screening of herbal extracts using agar well diffusion method In general, the obtained data in the present study showed that extracts of rosemary, cinnamon, clove and oregano confirmed the antibacterial activity against Staph. aureus, L. monocytogens, B. subtilis, E. coli and P. aeruginosa in agar well diffusion method. (Table 2) reviewed that inhibition of the oregano extract was stronger than that of the others, showing inhibition zones ranging from 23–30 mm
Gram-negative bacteria E. coli and P. aeruginosa were less susceptible to the inhibitory activity of all herbal extracts used in the experiment as compared to Gram-positive bacteria Staph. aureus, L. monocytogens and B. subtilis
Summary
Extraction was carried out using method described by [14] with some modification. 100 g crushed powder from each part of. Extraction was carried out using method described by [14] with some modification. 100 g crushed powder from each part of. Plant was individually immersed using500 ml of 95 percent ethanol taken in a flask of 1 liter capacity, the flask was kept shaking for 4 days at 150 rpm and room temperature. The solutions were first passed through a muslin cloth and filtrate collected were filtered again by using a filter paper i.e. Whatman’s filter paper No. to achieve a particle free solution. The filtrates were evaporated using rotary evaporator and kept at -80°C to be frozen before subjecting to freeze drying. The prepared aqueous extracts were collected in sample bottles and stored in refrigerator at 4°C before using
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
