Proposed mechanism of antibacterial mode of action of Caesalpinia bonducella seed oil against food-borne pathogens

The present study aimed to characterize a lactic acid bacterium Pediococcus pentosaceus 4I1, isolated from the intestine of fresh water fish sample Zacco koreanus. Biochemical analysis using the API 50 CHL kit and molecular characterization of 4I1 revealed its identity as a lactic acid bacterium Pediococcus pentosaceus 4I1. Further, cell free supernatant (CFS) of P. pentosaceus 4I1 exhibited significant (p<0.05) antibacterial effect as diameters of inhibition zones (16.5–20.4 mm) against the tested foodborne pathogenic bacteria with minimum inhibitory (MIC) and minimum bactericidal (MBC) concentration values found in the range of 250-500 and 500-1,000 µg/mL, respectively. Further, to confirm the efficacy of 4I1 on membrane permeability against foodborne pathogens, antibacterial mode of action of CFS of P. pentosaceus 4I1 against two selected bacteria Staphylococcus aureus KCTC-1621 (gram-positive) and Escherichia coli O157:H7 (gram-negative) was determined by measuring cell viable count, release of 260-nm absorbing materials, leakage of potassium ions and measurement of relative electrical conductivity of the bacterial cells treated at MIC concentration. The CFS of P. pentosaceus 4I1 revealed its mode of action on membrane integrity as confirmed by reduction in viable cell count, increased release of potassium ions (900 and 800 mM/L), loss of 260-nm absorbing materials (3.99 and 3.77 OD), and increase in relative electrical conductivity (9.9 and 9.7%) against the tested bacteria S. aureus KCTC-1621 and E. coli O157:H7, respectively. The above findings hypothesize that P. pentosaceus 4I1 compromised its mode of action on membrane integrity, suggesting its enormous potential in food and pharma industries.

Download Full-text

Characterization of lactic acid bacterium Pediococcus pentosaceus 4I1 from fresh water fish Zacco koreanus and its antibacterial mode of action

10.7287/peerj.preprints.2121v1 ◽

2016 ◽

Author(s):

Vivek K. Bajpai ◽

Jeong-Ho Han ◽

Irfan A. Rather ◽

Rajib Majumder ◽

Gyeong-Jun Nam ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacterium ◽

Mode Of Action ◽

Membrane Integrity ◽

Potassium Ions ◽

Fresh Water Fish ◽

Pediococcus Pentosaceus ◽

Water Fish ◽

Relative Electrical Conductivity

The present study aimed to characterize a lactic acid bacterium Pediococcus pentosaceus 4I1, isolated from the intestine of fresh water fish sample Zacco koreanus. Biochemical analysis using the API 50 CHL kit and molecular characterization of 4I1 revealed its identity as a lactic acid bacterium Pediococcus pentosaceus 4I1. Further, cell free supernatant (CFS) of P. pentosaceus 4I1 exhibited significant (p<0.05) antibacterial effect as diameters of inhibition zones (16.5–20.4 mm) against the tested foodborne pathogenic bacteria with minimum inhibitory (MIC) and minimum bactericidal (MBC) concentration values found in the range of 250-500 and 500-1,000 µg/mL, respectively. Further, to confirm the efficacy of 4I1 on membrane permeability against foodborne pathogens, antibacterial mode of action of CFS of P. pentosaceus 4I1 against two selected bacteria Staphylococcus aureus KCTC-1621 (gram-positive) and Escherichia coli O157:H7 (gram-negative) was determined by measuring cell viable count, release of 260-nm absorbing materials, leakage of potassium ions and measurement of relative electrical conductivity of the bacterial cells treated at MIC concentration. The CFS of P. pentosaceus 4I1 revealed its mode of action on membrane integrity as confirmed by reduction in viable cell count, increased release of potassium ions (900 and 800 mM/L), loss of 260-nm absorbing materials (3.99 and 3.77 OD), and increase in relative electrical conductivity (9.9 and 9.7%) against the tested bacteria S. aureus KCTC-1621 and E. coli O157:H7, respectively. The above findings hypothesize that P. pentosaceus 4I1 compromised its mode of action on membrane integrity, suggesting its enormous potential in food and pharma industries.

Download Full-text

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.

Download Full-text