Antimicrobial Activity of Roselle Hibiscus Sabdariffa Calyx Extracts on Culture Media and Carrots Against Multidrug‐Resistant Salmonella Strains Isolated from Raw Carrots

Abstract

Presence of antibiotic‐resistant Salmonella strains on raw carrots was evaluated, as was the antibacterial activity of roselle calyx extracts against any identified resistant Salmonella strains. One hundred samples of carrots were collected from markets in Pachuca, Mexico. Salmonella was isolated from the carrot samples by culture procedure. Susceptibilities to sixteen antibiotics were determined for the isolated Salmonella strains by standard test. Antibacterial activity versus the isolated strains was measured for roselle extracts produced with water, methanol, acetone and ethyl acetate. Finally, the antibacterial effect of roselle extracts, sodium hypochlorite, acetic acid and colloidal silver against Salmonella strains isolated from carrots was evaluated on contaminated carrots. Thirteen Salmonella strains were isolated from 11% of the carrot samples. All strains exhibited resistance to at least two of the tested antibiotics. Roselle extracts caused a greater reduction in concentration of Salmonella than the sodium hypochlorite, acetic acid and colloidal silver on contaminated carrots. Practical Applications Roselle Hibiscus sabdariffa calyx extracts exhibited antimicrobial activity on culture media and on carrots against multidrug‐resistant Salmonella strains. The information presented shows that water extract of roselle calyx may be a potentially useful addition to disinfection procedures of raw carrots in field, carrot processor plants, restaurants and home.

Behavior of thirteen foodborne bacteria on whole Hass avocado and potential of roselle calyx extracts as alternative disinfectant agents of avocado

“…Roselle calyx extracts have been used to disinfect carrots (Gutiérrez‐Alcántara, Gómez‐Aldapa, et al, ), tomatoes (Gutiérrez‐Alcántara, Rangel‐Vargas, et al, ), romaine lettuce, and alfalfa sprouts (Jaroni & Ravishankar, ), and organic leafy vegetables (romaine lettuce, iceberg lettuce, and baby spinach) (Moore et al, ). Gutiérrez‐Alcántara, Gómez‐Aldapa, et al () treated carrots contaminated with multidrug‐resistant Salmonella serotypes (Typhi, Typhimurium, Montevideo, and Gaminara) isolated from carrots.…”

“…Typhimurium (ATCC 14028), L. monocytogenes (ATCC 19115), S. aureus (ATCC 25923), S. flexneri (ATCC 12022), S . Typhi (strain SS6 isolated from raw tomatoes [Gutiérrez‐Alcántara, Rangel‐Vargas, et al, ]), S . Montevideo (strain Z6 isolated from raw carrots [Gutiérrez‐Alcántara, Gómez‐Aldapa, et al, ]), E. coli O157:H7 (E09; donated by E.F. Escartín of the Universidad Autónoma de Querétaro, México) , Vibrio cholerae O1 (87151, serotipe Inaba; donated by E.F. Escartín); E. coli pathotypes comprised three strains of each non‐O157‐STEC, EPEC, ETEC, and EIEC strains, and one of EAEC strain.…”

“…Roselle calyx extracts (aqueous, methanol, acetone, and ethyl acetate) were obtained as previously described (Gutiérrez‐Alcántara, Rangel‐Vargas, et al, ). Briefly, a sample (5 kg) of dehydrated roselle H. sabdariffa variety “Criolla de Oaxaca” calyces was used.…”

“…Previous studies used only aqueous roselle calyx extracts to disinfect romaine lettuce and alfalfa sprouts contaminated with Escherichia coli O157:H7, Salmonella and L. monocytogenes (Jaroni & Ravishankar, ) and organic iceberg lettuce and adult and baby spinach contaminated with Salmonella (Moore, Patel, Jaroni, Friedman, & Ravishankar, ). Recently, we reported the antimicrobial effect of four‐roselle calyx extracts (water, methanol, acetone, and ethyl acetate) against multidrug‐resistant Salmonella strains on carrots (Gutiérrez‐Alcántara, Gómez‐Aldapa, et al, ) and tomatoes (Gutiérrez‐Alcántara, Rangel‐Vargas, et al, ). However, no data are available regarding the activity of these roselle calyx extracts against S .…”

Detection of potential AcrAB-TolC multidrug efflux pump inhibitor in calyces extract of Hibiscus sabdariffa

“…The antimicrobial activity of H. sabdariffa has been reported against foodborne and food spoilage microorganisms, like E. coli O157:H7, is a major foodborne pathogen [23,37], also against Gram-negative bacteria such as Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus vulgaris, Salmonella enterica and some multidrug resistant Salmonella strains, in addition to some Gram-positive bacteria such as Bacillus subtilis, S. aureus, Staphylococcus epidermis, and Staphylococcus cereus [24,25,37,38].…”