scholarly journals Antibacterial Activity and Mechanism of Action of the Silver Ion in Staphylococcus aureus and Escherichia coli

2008 ◽  
Vol 74 (7) ◽  
pp. 2171-2178 ◽  
Author(s):  
Woo Kyung Jung ◽  
Hye Cheong Koo ◽  
Ki Woo Kim ◽  
Sook Shin ◽  
So Hyun Kim ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Mechanism Of Action ◽  
Antibacterial Effect ◽  
Silver Ion ◽  
Plate Count ◽  
E Coli ◽  
Count Method ◽  
Plate Count Method ◽  
Conventional Plate

ABSTRACT The antibacterial effect and mechanism of action of a silver ion solution that was electrically generated were investigated for Staphylococcus aureus and Escherichia coli by analyzing the growth, morphology, and ultrastructure of the bacterial cells following treatment with the silver ion solution. Bacteria were exposed to the silver ion solution for various lengths of time, and the antibacterial effect of the solution was tested using the conventional plate count method and flow cytometric (FC) analysis. Reductions of more than 5 log10 CFU/ml of both S. aureus and E. coli bacteria were confirmed after 90 min of treatment with the silver ion solution. Significant reduction of S. aureus and E. coli cells was also observed by FC analysis; however, the reduction rate determined by FC analysis was less than that determined by the conventional plate count method. These differences may be attributed to the presence of bacteria in an active but nonculturable (ABNC) state after treatment with the silver ion solution. Transmission electron microscopy showed considerable changes in the bacterial cell membranes upon silver ion treatment, which might be the cause or consequence of cell death. In conclusion, the results of the present study suggest that silver ions may cause S. aureus and E. coli bacteria to reach an ABNC state and eventually die.

scholarly journals Conventional versus the petrifilm method for the enumeration of different types of bacteria

1969 ◽  
Vol 73 (3) ◽  
pp. 183-187
Author(s):  
Fred Fernández-Coll ◽  
Luis Silva-Negrón
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Plate Count ◽  
Bacterial Populations ◽  
E Coli ◽  
Different Types ◽  
Plate Counts ◽  
Conventional Plate ◽  
Aerobic Plate Count

Performance of Petrifilm VRB and SM plates to enumerate different types of bacterial populations was evaluated. A total of 100 Petrifilms and 100 regular Petri plates were tested with each of 3 different bacterial populations in 4 experiments. The Petrifilm system was superior to the conventional pour plate methods, or at least not statistically different, in enumerating Escherichia coli (coliform) and a mixture of E. coli, Staphylococcus aureus and Serratia marcescens (total aerobic plate count). The Petrifilm method was superior to conventional plate counts in enumerating Pseudomonas aeruginosa (psychrotrophic plate count), when both incubations were at 21°-22° C for 96 h. If sustained in further experimentation, this last observation would mean that the Petrifilm SM system could be successfully used to detect bacterial populations in addition to those for which the system was originally intended.

scholarly journals Antibiogram Profiling and Thermal Inactivation of Staphylococcus aureus and Escherichia coli Isolated from Milk of Dharan, Nepal

2020 ◽  
pp. 81-87
Author(s):  
Susmita Phattepuri ◽  
Prince Subba ◽  
Arjun Ghimire ◽  
Shiv Nandan Sah
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Thermal Inactivation ◽  
Total Coliform ◽  
Plate Count ◽  
Diffusion Method ◽  
E Coli ◽  
Coliform Count ◽  
Z Value ◽  
D Values

Milk is an excellent medium for the growth of many bacteria. This study aimed to determine antibiotic profiling and thermal inactivation of Staphylococcus aureus and Escherichia coli isolated from raw milk of Dharan. Total viable count, total Staphylococcal count, and total coliform count were carried out by conventional microbiological methods. Identification was done on the basis of Gram staining and biochemical tests. The antibiotic susceptibility test of the isolates carried out by the modified Kirby-Baur disc diffusion method. Thermal inactivation of S. aureus and E. coli were carried out by subjecting to thermal treatment in a water bath. Total plate count ranged from 204×104 CFU/mL to 332×105 CFU/mL. Total staphylococcal count and total coliform count ranged from 14×105 CFU/mL to 8×106 CFU/mL and 11×104 CFU/mL to 3×106 CFU/mL respectively. S. aureus showed an increasing resistance patterns towards Ampicillin, Cefotixin, Carbenicillin and Cefotaxime. Ciprofloxacin, Erythromycin, Amikacin, Gentamycin, Azithromycin, and Chloramphenicol were found to be effective against S. aureus. All the E. coli isolates were resistant to Ampicillin and least resistant to Cefotixin. Chloramphenicol, Amikacin, Azithromycin, and Nalidixic acid were found highly effective to E. coli. The D-values for S. aureus at 56°C, 58°C and 60°C were 1.36 min, 1.19 min, and 1.09 min respectively. The Z-value was 14.92°C. While D-values were obtained as 0.98 min, 0.75 min, and 0.57 min for E. coli at 56° C, 58° C and 60° C respectively, and Z-value was 9.75° C. Hence, S. aureus was found to be more heat resistant than E. coli.

scholarly journals Antibacterial effect of Dimethyl sulfoxide extract of Aloe vera (Aloe barbadensis) leaf gel against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae

Mediscope ◽  
2020 ◽  
Vol 7 (2) ◽  
pp. 67-74 ◽  
Author(s):  
Syed Didarul Haque ◽  
Abu Md Mayeenuddin Al Amin ◽  
Baishakhi Islam ◽  
Nazia Nazneen ◽  
Syeda Noorjahan Karim ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Klebsiella Pneumoniae ◽  
Dimethyl Sulfoxide ◽  
Antibacterial Effect ◽  
Aloe Vera ◽  
Biologically Active ◽  
Diffusion Method ◽  
E Coli

An exploratory study based on laboratory experiment was carried out to determine the antibacterial effect of Dimethyl sulfoxide (DMSO) extract of Aloe vera leaf gel (DAE) against standard strains of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae in the Department of Pharmacology & Therapeutics in collaboration with the Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh. DMSO extract was used in five different concentrations (100, 200, 300, 400 and 500 μg/ml). Dose dependent inhibitory effect was seen against the test organisms using disc diffusion method. Zone of inhibition (ZOI) were 8 mm, 13 mm, 15 mm, 16 mm and 21 mm against S. aureus; 0 mm, 8 mm, 13 mm, 15 mm and 18 mm against P. aeruginosa; 8 mm, 11 mm, 13 mm, 16 mm and 20 mm against E. coli; 0 mm, 9 mm, 12 mm, 14 mm and 18 mm against K. pneumoniae at 100, 200, 300, 400 and 500 μg/ml respectively. The minimum inhibitory concentration (MIC) was assessed by broth dilution technique. The MICs of DAE for S. aureus, P. aeruginosa, E. coli and K. pneumoniae were 300 μg/ml, 400 μg/ml, 400 μg/ml and 450 μg/ml respectively. From the study it was observed that DMSO extract of Aloe vera leaf gel possesses antibacterial effect against the test pathogens. The findings highlight the need for further extensive study to detect and isolate the biologically active ingredients present in the Aloe vera leaves which are responsible for antibacterial effect. Hopefully, that would lead to the discovery of new and more potent antimicrobial agents originated from Aloe vera. Mediscope Vol. 7, No. 2: July 2020, Page 67-74

scholarly journals Fluorescence Assay for Evaluating Microbicidal Activity of Hand Antiseptics

2015 ◽  
Vol 81 (21) ◽  
pp. 7443-7447
Author(s):  
Rosa M. Lopez-Gigosos ◽  
Alberto Mariscal ◽  
Eloisa Mariscal-Lopez ◽  
Mario Gutierrez-Bedmar ◽  
Joaquin Fernandez
Keyword(s):  
Plate Count ◽  
Content Type ◽  
E Coli ◽  
Glucuronidase Activity ◽  
Count Method ◽  
Fluorescence Methods ◽  
Fluorescence Level ◽  
Assay Time ◽  
Plate Count Method ◽  
Time Required

ABSTRACTWe developed a fluorescent β-d-glucuronidase activity (BGA)-based assay for detecting and quantifyingEscherichia coliin samples to assess the biocide efficacy of hand antiseptics. The fluorescence level is proportional to the number of viableE. coliorganisms present. We compared our assay results to those of theE. coliplate count method specified by the European standard for testing hygienic hand rub disinfectant products (EN1500). The plate count method requires excessive handling and materials and is not valid if the number of organisms per plate is too low or high for counting in many of the samples. We optimized the fluorescent assay based on the cleavage of 4-methylumbelliferyl-β-d-glucuronide by adding 4-nitrophenyl-β-d-glucuronide, a nonfluorogenic BGA substrate, to induce glucuronidase activity and reduce assay time. Furthermore, our method can be automated and eliminates the need for multiple dilutions. Fluorescence was temporally monitored, and the time required to reach a specific value of fluorescence was correlated with the initial number of viableE. coliorganisms on the samples. There was a positive correlation (P< 0.05) with a high correlation coefficient (R2= 0.82) between theE. colicounts by plate count and fluorescence methods. Reported effects in fluorescent BGA were compared to the EN1500 plate count method with five hand disinfectants. We found our method more advantageous, because it was as sensitive as the EN1500 method, requires less time to complete, and is less expensive and less laborious than conventional plating techniques.

scholarly journals Uji Efek Antibakteri Jamur Endofit Akar Bakau Rhizophora stylosa Terhadap Bakteri Staphylococcus aureus dan Escherichia coli

2014 ◽  
Vol 2 (1) ◽  
Author(s):  
Michele Sumampouw
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Endophytic Fungi ◽  
Pathogenic Bacteria ◽  
Antibacterial Effect ◽  
Inhibition Zone ◽  
Potato Dextrose Agar ◽  
Rhizophora Stylosa ◽  
E Coli

Abstract: The aim of this study is to investigate the antibacterial effect of endophytic fungi originated from the root of mangrove Rhizophora stylosa growing on Mangrove Plantation Area around DAS Simpang 5 Jl. Piere Tendean Manado. The method of this research was using combination of PDA and NA media. Two species of endophytic fungi were extracted from the root of R. stylosa, black mycelium fungi as isolate A and brown mycelium fungi as isolate B. The activities of both isolates were tested against pathogenic bacteria Staphylococcus aureus and Escherichia coli. The result showed the same inhibition zone of isolate A and B to S. aureus, while, isolate A showed bigger the inhibition zone in comparison to isolate B against E. coli. As a conclusion, the endophytic fungi taken from the root of R. stylosa have antibacterial activity toward S. aureus and E. coli. Keywords: endophytic fungi, Rhizophora stylosa, antibacterial, Staphylococcus aureus, Escherichia coli.   Abstrak: Penelitian ini bertujuan untuk melihat adanya efek antibakteri dari jamur endofit yang diambil dari akar bakau Rhizophora stylosa yang ditanam di sekitar Perairan Daerah Aliran Sungai Simpang Lima Jl. Piere Tendean Manado. Metode penelitian dilakukan dengan menggunakan kombinasi media Potato Dextrose Agar (PDA) dan Nutrient Agar (NA). Dari akar bakau R. stylosa diperoleh dua  jenis jamur endofit yaitu isolat A dengan karateristik miselium jamur berwarna hitam dan isolat B yang dengan karakteristik miselium berwarna coklat. Kedua isolat ini selanjutnya diujikan aktivitasnya terhadap bakteri Staphylococcus aureus dan Escherichia coli. Hasil penelitian menunjukkan isolat A dan B memberikan  zona hambat yang sama terhadap bakteri Staphylococcus aureus dan pada bakteri Escherichia coli isolat A menunjukkan diameter zona hambat yang lebih besar dibandingkan isolat B. Kesimpulan, Jamur endofit yang diisolasi dari akar bakau R. Stylosa memiliki efek antibakteri terhadap pertumbuhan bakteri S. aureus dan E. coli. Kata kunci: jamur endofit, Rhizophopra stylosa, antibakteri, Staphylococcus aureus, Escherichia coli.

scholarly journals Prevalence of Escherichia Coli, Salmonella Sp, Staphylococcus Aureus Bacteria in Chicken Meat of Traditional Market Surabaya City

2021 ◽  
Vol 8 (2) ◽  
pp. 193-204
Author(s):  
Ulfa Dwi Karisma ◽  
Nurul Wiqoyah ◽  
Suhintam Pusarawati
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Chicken Meat ◽  
Plate Count ◽  
Test Results ◽  
E Coli ◽  
Traditional Markets ◽  
Two Samples ◽  
Contaminated Food ◽  
And Staphylococcus Aureus

Foodborne disease is a disease caused by contaminated food. Chicken meat is very susceptible to contamination by bacteria. Escherichia coli, Salmonella sp, and Staphylococcus aureus are types of bacteria found in chicken meat. The purpose of this study was to see how many Escherichia coli, Salmonella sp, and Staphylococcus aureus colonies in raw chicken meat in traditional markets in Surabaya City. The research sample used was 30 samples of chicken meat taken in 5 traditional markets in Surabaya. Six chicken meat sellers were taken with 1 sample and put in the sterile tube from each market. The test was carried out using the Total Plate Count (TPC) method. The TPC test results showed that all samples were contaminated with E. coli, with the most colony being 2.2X10-7 CFU/g while the minor colony was 5X10-4 CFU/g. There are two samples contaminated with Salmonella sp, in the G market and the W market, with code D6 4.7X10-6 CFU/g and code E5 1X10-6 CFU/g. Meanwhile, S. aureus was only found in the W market with sample codes E1 & E6, and each sample had a colony of 2.7X 10-7 CFU/g and 2X10-5 CFU/g.

scholarly journals ANTIBACTERIAL ACTIVITY OF ROBUSTA COFFEE (COFFEA CANEPHORA L.) LEAVES TO STAPHYLOCOCCUS AUREUS AND ESCHERICHIA COLI

2019 ◽  
pp. 113-115
Author(s):  
ZAMHARIRA MUSLIM ◽  
YONANIKO DEPHINTO
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Ethyl Acetate ◽  
Antibacterial Effect ◽  
Ethyl Acetate Fraction ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Robusta Coffee

Objective: This research aims to analyze the ability of robusta coffee leaves fraction extract to inhibit the growth of Staphylococcus aureus and Escherichia coli and also determine the minimum inhibitory concentration (MIC). Methods: Antibacterial activity evaluated by the disc diffusion method observed in four types of fraction of extract robusta coffee leaves (n-hexane, ethyl acetate, ethanol, and water). Each extract divided into three various concentrations, 5%, 10%, and 15%. Determination of antimicrobial activity in vitro by the disk diffusion method. Results: Ethyl acetate fraction of coffee leaves extract produced the largest diameter zone of inhibition of bacterial growth compared to other extraction fractions of 17.28 mm in E. coli and 18.58 mm in S. aureus. The MIC of coffee leaves extract fraction water, ethyl acetate, and n-hexane on E. coli and S. aureus is 5%, while the fraction ethanol MIC is 10%. Conclusion: The antibacterial effect of ethyl acetate fraction of coffee leaves extract showed an antibacterial effect that was better than the fraction of n-hexane, ethanol, and water.

Destruction de Microbacterium lacticum, Escherichia coli et Staphylococcus aureus au cours du séchage du lait par atomisation. I. Dénombrement sélectif des bactéries survivantes

1977 ◽  
Vol 23 (6) ◽  
pp. 716-720
Author(s):  
A. Chopin ◽  
G. Mocquot ◽  
Y. Le Graet
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Spray Drying ◽  
Skim Milk ◽  
Resistant Mutant ◽  
Plate Count ◽  
Mannitol Salt Agar ◽  
E Coli ◽  
Plate Count Agar ◽  
Plate Counts

In this paper a method which allows the measure of microbial death rate during spray-drying by means of a streptomycin-resistant mutant that can be grown on a streptomycin-containing agar is described. Plate counts of Microbacterium lacticum, Escherichia coli, and Staphylococcus aureus recovered from skim milk powders were done on plate count agar in the presence and absence of streptomycin and on various selective media. The powders were produced from evaporated milk previously inoculated with those organisms.Our results showed that the proposed method allows the recovery of 78% of M. lacticum, 61% of E. coli, and 100% of S. aureus that survived spray-drying. Recoveries of surviving E. coli on violet bile agar and brilliant green bile 2% were 34% and 29% respectively. Baird-Parker and mannitol salt agar media allow the recovery of all surviving S. aureus, thus showing that S. aureus cells did not lose their ability to grow in media containing 7.5% NaCl. Our results show that physiological injury of the cells during spray-drying differs from injury due to heating only. [Traduit par le journal]

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