ANTIBACTERIAL MODE OF ACTION OF THE ROSEMARY/EUCALYPTUS OIL COMBINATION ON THE MEMBRANE INTEGRITY OF SELECTED FOOD BORNE PATHOGENS.

The antibacterial mechanism of action of Caesalpinia bonducella seed oil on membrane permeability of Listeria monocytogenes NCIM 24563 (MIC: 2 mg/mL) and Escherichia coli ATCC 25922 (MIC: 4 mg/mL) was determined by measuring the extracellular ATP concentration, release of 260-nm absorbing materials, leakage of potassium ions and measurement of relative electrical conductivity of the bacterial cells treated at MIC concentration. Its mode of action on membrane integrity was confirmed by release of extracellular ATP (1.42 and 1.33 pg/mL), loss of 260-nm absorbing materials (4.36 and 4.19 optical density), leakage of potassium ions (950 and 1000 mmol/L) and increase in relative electrical conductivity (12.6 and 10.5%) against food-borne pathogenic bacteria L. monocytogenes and E. coli, respectively. These findings propose that C. bonducella oil compromised its mode of action on membrane integrity, suggesting its enormous food and pharmacological potential.

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Chemical characterization and mode of action of Ligustrum lucidum flower essential oil against food-borne pathogenic bacteria

Bangladesh Journal of Pharmacology ◽

10.3329/bjp.v11i1.25487 ◽

2016 ◽

Vol 11 (1) ◽

pp. 269 ◽

Cited By ~ 2

Author(s):

Vivek K. Bajpai ◽

Siddhartha Singh ◽

Archana Mehta

Keyword(s):

Essential Oil ◽

Mode Of Action ◽

Pathogenic Bacteria ◽

Membrane Integrity ◽

Chemical Characterization ◽

Mass Spectrometry Analysis ◽

Gas Chromatography Mass Spectrometry ◽

Spectrometry Analysis ◽

Ligustrum Lucidum ◽

Food Borne

Current research analyzes the chemical composition of Ligustrum lucidum flower essential oil obtained by the hydrodistillation, and examines its anti-microbial mode of action against food-borne pathogenic bacteria. Gas chromatography-mass spectrometry analysis of the oil resulted in the determination of 44 different compounds, representing 85.2% of the total oil. The oil (1 mg/disc) showed significant antibacterial effect as diameters of inhibition zones (14.6 ± 0.2 – 19.7 ± 0.3 mm), as well as minimum inhibitory and minimum bactericidal concentrations values (250–1000 and 250–2000 µg/mL), respectively. Based on the susceptibility, L. lucidum flower oil revealed its mode of action on membrane integrity as confirmed by increased release of extracellular ATP (2.5 and 2.2 pg/mL), leakage of potassium ions (950 and 900 mM/L), loss of 260-nm absorbing materials (4.2 and 3.9 optical density), and increase in relative electrical conductivity (10.6 and 9.8%) against Staphylococcus aureus KCTC-1621 (Gram-positive) and Salmonella enterica ATCC-4731 (Gram-negative), respectively.

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Antibacterial mode of action of Cudrania tricuspidata fruit essential oil, affecting membrane permeability and surface characteristics of food-borne pathogens

Food Control ◽

10.1016/j.foodcont.2013.01.032 ◽

2013 ◽

Vol 32 (2) ◽

pp. 582-590 ◽

Cited By ~ 208

Author(s):

Vivek K. Bajpai ◽

Ajay Sharma ◽

Kwang-Hyun Baek

Keyword(s):

Essential Oil ◽

Membrane Permeability ◽

Mode Of Action ◽

Surface Characteristics ◽

Cudrania Tricuspidata ◽

Food Borne Pathogens ◽

Food Borne

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Combined Effect of Enterocin and Lipase From Enterococcus faecium NCIM5363 Against Food Borne Pathogens: Mode of Action Studies

Current Microbiology ◽

10.1007/s00284-012-0138-z ◽

2012 ◽

Vol 65 (2) ◽

pp. 162-169 ◽

Cited By ~ 8

Author(s):

Vrinda Ramakrishnan ◽

Bhaskar Narayan ◽

Prakash M. Halami

Keyword(s):

Mode Of Action ◽

Enterococcus Faecium ◽

Combined Effect ◽

Food Borne Pathogens ◽

Food Borne

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Toyoncin—a novel leaderless bacteriocin produced by Bacillus toyonensis XIN-YC13 that specifically targets B. cereus and Listeria monocytogenes

Applied and Environmental Microbiology ◽

10.1128/aem.00185-21 ◽

2021 ◽

Author(s):

Juanjuan Wang ◽

Haitao Xu ◽

Shu Liu ◽

Baolong Song ◽

Hualin Liu ◽

...

Keyword(s):

Antimicrobial Activity ◽

Listeria Monocytogenes ◽

Amino Acid ◽

Cell Membrane ◽

Membrane Damage ◽

Membrane Integrity ◽

Heat Stability ◽

Important Food ◽

Food Borne Pathogens ◽

Food Borne

Bacteriocins have attracted increasing interest because of their potential as natural preservatives. Recent studies showed that the Bacillus cereus group is a prominent producer of bacteriocins. Using a laboratory-based screening strategy, we identified a strain in the B. cereus group, B. toyonensis XIN-YC13, with antimicrobial activity against B. cereus. A novel, 70-amino acid-long leaderless bacteriocin, toyoncin, was purified from the culture supernatant of strain XIN-YC13 and its molecular mass was found to be 7817.1012 Da. Toyoncin shares no similarity with any other known bacteriocins, and its N-terminal amino acid is formylmethionine rather than methionine. Toyoncin shows good pH and heat stability and exhibits specific antimicrobial activity against two important food-borne pathogens, B. cereus and Listeria monocytogenes. Additionally, toyoncin exerts bactericidal activity and induces cell membrane damage. Toyoncin can also inhibit the outgrowth of B. cereus spores. The preservation assays showed that toyoncin effectively suppressed or eradicated B. cereus and L. monocytogenes in pasteurized skim milk. These results suggest that toyoncin can be used as a new bio-preservative against B. cereus and L. monocytogenes in the food industry. Importance: We identified a novel leaderless bacteriocin, toyoncin, produced by B. toyonensis XIN-YC13. Toyoncin shows good pH and heat stability; has specific antimicrobial activity against, B. cereus and L. monocytogenes (two important food-borne pathogens), and destroys their cell membrane integrity. Toyoncin inhibited the outgrowth of B. cereus spores and effectively inhibited or eliminated B. cereus and L. monocytogenes in a milk model system. These results indicate the potential of toyoncin as a food preservative.

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