Abstract
In this study, the capsaicin content of chile pepper extracts from 29 unexplored varieties of Capsicum (twenty five varieties of Capsicum chinense and five of Capsicum annuum) was quantified and correlated with the antimicrobial potential against bacterial and fungal pathogens. The capsaicin content and bactericidal activity against numerous human pathogens (Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, Candida albicans) was compared to identify the most effective chile pepper varieties in the treatment of bacterial and fungal pathogens. The capsaicin content of the tested varieties varied from 29 to 42,633 ppm (139 - 682,135 SHU). On average, the fruits of C. chinense cultivars contained much higher concentrations of capsaicin than C. annuum cultivars. The undiluted chile peppers extracts with capsaicin concentrations greater than 25,000 SHU demonstrated bactericidal and antifungal effects. Overall, it was determined that L. monocytogenes and S. aureus were more susceptible to the antimicrobial effects of capsaicin than Salmonella and E. coli O157:H7, while C. albicans was markedly more susceptible than all bacterial species examined. The extract of the sixth most pungent cultivar, C. chinense Bhut Jolokia Red, showed the greatest antimicrobial potency of all screened peppers. The antimicrobial activity of pepper extracts was not directly correlated with increasing capsaicin concentrations, indicating that various Capsicum cultivars may possess distinct capsaicin derivatives. This is the first study which showed the relationship between capsaicin contents in different Capsicum varieties and their antimicrobial potential, and opens avenues in the study of capsaicin derivatives and their role in health and medicines. Key words: Capsicum, pathogen, capsaicin, peppers, antimicrobial, bactericidal.
Highlights
The emergence of antibiotic resistance has prompted scientists to explore medicinal plants, to ascertain claims of efficacy and safety, and to develop phytochemical based new drugs as alternatives to antibiotics
L. monocytogenes Scott A, Salmonella Typhimurium LT2, and Escherichia coli O157:H7 EDL933 bacterial cultures were obtained from the Food Safety Microbiology Laboratory (Department of Food Science and Nutrition), while the S. aureus 6538 and C. albicans ATCC 10231 cultures were obtained from the Hegeman Laboratory (Department of Horticultural Science), at the University of Minnesota – Twin Cities
L. monocytogenes was streak plated on brain heart infusion (BHI) agar media, while the other bacterial strains were plated on tryptic soy agar (TSA) agar medium
Summary
The emergence of antibiotic resistance has prompted scientists to explore medicinal plants, to ascertain claims of efficacy and safety, and to develop phytochemical based new drugs as alternatives to antibiotics. All plants of the Capsicum genus produce varied amount of capsaicin, only a few chile pepper varieties have been scientifically examined for their antimicrobial properties against bacterial and fungal pathogens. The antimicrobial activity of chile pepper extracts have been tested on a small selection of Capsicum annum, Capsicum baccatum, Capsicum frutescens, Capsicum pubescens, and Capsicum chinense cultivars, representing some of the milder members of the genus Capsicum (Cichewicz and Thorpe, 1996; Sanatombi and Sharma, 2008; Al Othman et al, 2011; Dorantes et al, 2000; Bacon et al, 2017). C. chinense varieties with extremely high capsaicin concentrations, such as the Trinidad Moruga Scorpion, Trinidad Douglah, Trinidad 7-Pot, Trinidad Scorpion, and Bhut Jolokia (“Ghost Pepper”) have never been tested for medicinal use (Omolo et al, 2014; Mills-Robertson et al, 2012)
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
