scholarly journals Maipomycin A, a Novel Natural Compound With Promising Anti-biofilm Activity Against Gram-Negative Pathogenic Bacteria

2021 ◽  
Vol 11 ◽  
Author(s):  
Junliang Zhang ◽  
Xiaoyan Liang ◽  
Shiling Zhang ◽  
Zhiman Song ◽  
Changyun Wang ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Pathogenic Bacteria ◽  
Complex Structure ◽  
Iron Chelator ◽  
Gram Negative Bacteria ◽  
Inhibition Activity ◽  
Biofilm Inhibition ◽  
Gram Negative ◽  
X Ray Crystallography ◽  
Actinomycete Strain

Pathogenic bacterial biofilms play an important role in recurrent nosocomial and medical device-related infections. Once occurred, the complex structure of the biofilm promotes the development of antibiotic resistance and becomes extremely difficult to eradicate. Here we describe a novel and effective anti-biofilm compound maipomycin A (MaiA), which was isolated from the metabolites of a rare actinomycete strain Kibdelosporangium phytohabitans XY-R10. Its structure was deduced from analyses of spectral data and confirmed by single-crystal X-ray crystallography. This natural product demonstrated a broad spectrum of anti-biofilm activities against Gram-negative bacteria. Interestingly, the addition of Fe(II) or Fe(III) ions could block the biofilm inhibition activity of MaiA because it is an iron chelator. However, not all iron chelators showed biofilm inhibition activity, suggesting that MaiA prevents biofilm formation through a specific yet currently undefined pathway. Furthermore, MaiA acts as a synergist to enhance colistin efficacy against Acinetobacter baumannii. Our results indicate that MaiA may potentially serve as an effective antibiofilm agent to prevent Gram-negative biofilm formation in future clinical applications.

scholarly journals Antimicrobial and antibiofilm properties of essential oils from Piper marginatum Jacq.

2021 ◽  
Vol 10 (11) ◽  
pp. e514101119967
Author(s):  
Ana Lúcia Mendes dos Santos ◽  
Filipe Augusto Matos Araújo ◽  
Érika da Silva Matisui ◽  
Luiz Antonio Mendonça Alves da Costa ◽  
Alexandre José Macêdo ◽  
...  
Keyword(s):  
Essential Oils ◽  
Biofilm Formation ◽  
Pathogenic Bacteria ◽  
Inhibitory Concentration ◽  
Folk Medicine ◽  
Gram Negative Bacteria ◽  
Biofilm Inhibition ◽  
Future Developments ◽  
Phytochemical Constituents ◽  
Amazonian Region

A low shrub growing in the Amazonian region, Piper marginatum Jacq. has been related to the treatment of a disease variety in folk medicine, however, still lacking scientific support. This study aimed to describe the composition of essential oils obtained from leaves (EOL) and branches (EOB) of P. marginatum and their antimicrobial effects on six relevant pathogenic bacteria. A combination of GC-FID and GC-MS was used to identify the phytochemical constituents. As antimicrobial assays, the oils were screened at the minimum inhibitory concentration (MIC) of 3 µg/ml for planktonic and biofilm inhibition. EOL revealed the presence of trans–nerolidol, o–cymene, spathulenol, elemicin, and α–copaene, while EOB composition was mainly of myristicin, trans-caryophyllene, trans-nerolidol, caryophyllene oxide, α–copaene, γ–muurolene and spathulenol. The strongest inhibition of planktonic growth was achieved against Pseudomonas aeruginosa (EOB) and Escherichia coli (EOB). Overall, Gram negative bacteria were more sensitive to both EOB/EOL showing less ability of growth and biofilm formation. The Gram-positive strains seemed to react to the essential oils by massive adhesion. Our results corroborate the relevance of Piperaceae and indicate the possible use of P. marginatum in future developments of antimicrobials.

Antibiotics Application Strategies to Control Biofilm Formation in Pathogenic Bacteria

2020 ◽  
Vol 21 (4) ◽  
pp. 270-286 ◽  
Author(s):  
Fazlurrahman Khan ◽  
Dung T.N. Pham ◽  
Sandra F. Oloketuyi ◽  
Young-Mog Kim
Keyword(s):  
Biofilm Formation ◽  
Pathogenic Bacteria ◽  
Extracellular Polymeric Substances ◽  
Quorum Quenching ◽  
Resistance Mechanisms ◽  
Bacterial Biofilm ◽  
Bacterial Cells ◽  
High Concentration ◽  
Biofilm Inhibition ◽  
Abiotic Surfaces

Background: The establishment of a biofilm by most pathogenic bacteria has been known as one of the resistance mechanisms against antibiotics. A biofilm is a structural component where the bacterial community adheres to the biotic or abiotic surfaces by the help of Extracellular Polymeric Substances (EPS) produced by bacterial cells. The biofilm matrix possesses the ability to resist several adverse environmental factors, including the effect of antibiotics. Therefore, the resistance of bacterial biofilm-forming cells could be increased up to 1000 times than the planktonic cells, hence requiring a significantly high concentration of antibiotics for treatment. Methods: Up to the present, several methodologies employing antibiotics as an anti-biofilm, antivirulence or quorum quenching agent have been developed for biofilm inhibition and eradication of a pre-formed mature biofilm. Results: Among the anti-biofilm strategies being tested, the sub-minimal inhibitory concentration of several antibiotics either alone or in combination has been shown to inhibit biofilm formation and down-regulate the production of virulence factors. The combinatorial strategies include (1) combination of multiple antibiotics, (2) combination of antibiotics with non-antibiotic agents and (3) loading of antibiotics onto a carrier. Conclusion: The present review paper describes the role of several antibiotics as biofilm inhibitors and also the alternative strategies adopted for applications in eradicating and inhibiting the formation of biofilm by pathogenic bacteria.

Effectiveness of Trisodium Phosphate, Acidified Sodium Chlorite, Citric Acid, and Peroxyacids against Pathogenic Bacteria on Poultry during Refrigerated Storage

2007 ◽  
Vol 70 (9) ◽  
pp. 2063-2071 ◽  
Author(s):  
ELENA del RÍO ◽  
REBECA MURIENTE ◽  
MIGUEL PRIETO ◽  
CARLOS ALONSO-CALLEJA ◽  
ROSA CAPITA
Keyword(s):  
Citric Acid ◽  
Salmonella Enteritidis ◽  
Pathogenic Bacteria ◽  
Trisodium Phosphate ◽  
Sodium Chlorite ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Microbial Group ◽  
And Control

The effects of dipping treatments (15 min) in potable water or in solutions (wt/vol) of 12% trisodium phosphate (TSP), 1,200 ppm acidified sodium chlorite (ASC), 2% citric acid (CA), and 220 ppm peroxyacids (PA) on inoculated pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Salmonella Enteritidis, Escherichia coli, and Yersinia enterocolitica) and skin pH were investigated throughout storage of chicken legs (days 0, 1, 3, and 5) at 3 ± 1°C. All chemical solutions reduced microbial populations (P < 0.001) as compared with the control (untreated) samples. Similar bacterial loads (P > 0.05) were observed on water-dipped and control legs. Type of treatment, microbial group, and sampling day influenced microbial counts (P < 0.001). Average reductions with regard to control samples were 0.28 to 2.41 log CFU/g with TSP, 0.33 to 3.15 log CFU/g with ASC, 0.82 to 1.97 log CFU/g with CA, and 0.07 to 0.96 log CFU/g with PA. Average reductions were lower (P < 0.001) for gram-positive (0.96 log CFU/g) than for gram-negative (1.33 log CFU/g) bacteria. CA and ASC were the most effective antimicrobial compounds against gram-positive and gram-negative bacteria, respectively. TSP was the second most effective compound for both bacterial groups. Average microbial reductions per gram of skin were 0.87 log CFU/g with TSP, 0.86 log CFU/g with ASC, 1.39 log CFU/g with CA, and 0.74 log CFU/g with PA for gram-positive bacteria, and 1.28 log CFU/g with TSP, 2.03 log CFU/g with ASC, 1.23 log CFU/g with CA, and 0.78 log CFU/g with PA for gram-negative bacteria. With only a few exceptions, microbial reductions in TSP- and ASC-treated samples decreased and those in samples treated with CA increased throughout storage. Samples treated with TSP and samples dipped in CA and ASC had the highest and lowest pH values, respectively, after treatment. The pH of the treated legs tended to return to normal (6.3 to 6.6) during storage. However, at the end of storage, the pH of legs treated with TSP remained higher and that of legs treated with CA remained lower than normal.

scholarly journals Antimicrobial Activity of Gardenia jasminoides Callus and Crude Leaf Extracts for some Organic Solvents against some Pathogenic Bacteria and Yeasts

2014 ◽  
Vol 8 (3) ◽  
pp. 40-45
Author(s):  
Zina Hashem Shehab ◽  
Huda Suhail Abid ◽  
Sumaya Fadhil Hamad ◽  
Sara Haitham
Keyword(s):  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Pathogenic Bacteria ◽  
Saccharomyces Boulardii ◽  
Gram Negative Bacteria ◽  
Proteus Vulgaris ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Gardenia Jasminoides

The study was conducted to evaluate the inhibitory activity of methanol extract of Gardenia jasminoides leaves compared with leaf crude extracts for some organic solvents namely Methanol, Ethanol, Petroleum ether, Asetone and Chloroform on growth of some pathogenic bacteria and yeast, which included four gram positive isolates Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes and Bacillus cereus and gram negative isolates Escherichia coli, Salmonella typhi, Proteus vulgaris and Pseudomonas aeruginosa and some yeasts Candida albicans and Saccharomyces boulardii, by using well diffusion method. The inhibitory activity of extracts in the tested bacterial strains and yeasts was varied according to the type of extracting solvents and are tested microorganisms. The methanol callus extract which grown on Murashige and Skoog (MS) media by using (Naphthalen acitic acid) NAA and (Benzyle adenine) BA as growth regulator highly effective as compared to the other extracts as for inhibition of three gram positive bacteria and three gram negative bacteria,which include Staphylococcus aureus and, Proteus vulgaris, followed by acetone and ethanolic extracts which include two gram positive bacteria and two gram negative bacteria. All extracts had highly effect in growth of Candida albicans while all crude extracts didn’t show any sensitivity against Saccharomyces boulardii, and when we’d done (High Performance Liquid Chromatography) HPLC test for detection of some active compound we found Quinic acid, Iridiods glycosides and Crocin which its rate in fresh callus was higher than fresh leaves.

scholarly journals Using sub-micron silver-nanoparticle based films to counter biofilm formation by Gram-negative bacteria

2018 ◽  
Vol 442 ◽  
pp. 288-297 ◽  
Author(s):  
A.R. Gillett ◽  
S.N. Baxter ◽  
S.D. Hodgson ◽  
G.C. Smith ◽  
P.J. Thomas
Keyword(s):  
Silver Nanoparticle ◽  
Biofilm Formation ◽  
Gram Negative Bacteria ◽  
Gram Negative

scholarly journals Antimicrobial Susceptibility Pattern of Gram-Negative Bacterial Isolates from Raw Chicken Meat Samples

2019 ◽  
Vol 6 ◽  
pp. 89-95
Author(s):  
Neha Gautam ◽  
Rojan Poudel ◽  
Binod Lekhak ◽  
Milan Kumar Upreti
Keyword(s):  
Antimicrobial Resistance ◽  
Pathogenic Bacteria ◽  
Chicken Meat ◽  
Food Microbiology ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Kathmandu Valley ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Meat Samples

Objectives: This research aims to study the microbial quality of chicken meat available in retail shop of Kathmandu Valley. Methods:  This Study was conducted from June to December 2018 in three different districts of Kathmandu Valley. Samples were collected in sterile plastic bags, labeled properly and stored in an icebox and transported to the Food Microbiology laboratory of Golden Gate International College.  During sample preparation, 25 grams of each sample was taken and transferred to sterile flasks containing 225 ml of buffered peptone water. Potential pathogenic Gram-negative bacteria were isolated by using respective selective media and identified by biochemical test. Antibiotic susceptibility profile of isolates was carried out by Kirby-Bauer disc diffusion method according to CLSI 2017 guideline. Results: Of total 81 chicken meat samples processed; 201 Gram negative bacteria were isolated.  E. coli (100%) was the dominant Gram-negative isolates, followed by Citrobacter spp (62.96%), Pseudomonas spp (40.74%), Proteus spp (19.75%), Salmonella spp (16.04%) and Klebsiella spp (8.64%) respectively. No any multidrug isolates were detected. Conclusion: The study showed that the raw chicken meat samples of Kathmandu valley was highly contaminated with Gram negative potential pathogenic bacteria. Antimicrobial resistance pattern shown by the isolates may indicates that there is not overuse of drug in animals and the less chance of risk of increasing antimicrobial resistance.

scholarly journals Relationship Between Membrane Vesicles, Extracellular ATP and Biofilm Formation in Antarctic Gram-Negative Bacteria

2020 ◽  
Author(s):  
Nicolas Baeza ◽  
Elena Mercade
Keyword(s):  
Biofilm Formation ◽  
Membrane Vesicles ◽  
Metabolic Cost ◽  
Extracellular Atp ◽  
Gram Negative Bacteria ◽  
Bacterial Survival ◽  
Gram Negative ◽  
Two Factors ◽  
And Control

Abstract Biofilms offer a safe environment that favors bacterial survival; for this reason, most pathogenic and environmental bacteria live integrated in biofilm communities. The development of biofilms is complex and involves many factors, which need to be studied in order to understand bacterial behavior and control biofilm formation when necessary. We used a collection of cold-adapted Antarctic Gram-negative bacteria to study whether their ability to form biofilms is associated with a capacity to produce membrane vesicles and secrete extracellular ATP. In most of the studied strains, no correlation was found between biofilm formation and these two factors. Only Shewanella vesiculosa M7T secreted high levels of extracellular ATP, and its membrane vesicles caused a significant increase in the speed and amount of biofilm formation. In this strain, an important portion of the exogenous ATP was contained in membrane vesicles, where it was protected from apyrase treatment. These results confirm that ATP influences biofilm formation. Although the role of extracellular ATP in prokaryotes is still not well understood, the metabolic cost of its production suggests it has an important function, such as a role in biofilm formation. Thus, the liberation of extracellular ATP through membrane vesicles and its function deserve further study.

scholarly journals The effects of biofilm and selective mixed culture on the electricity outputs and wastewater quality of tempe liquid waste based microbial fuel cell

REAKTOR ◽  
2018 ◽  
Vol 18 (2) ◽  
pp. 84
Author(s):  
Tania Surya Utami ◽  
Rita Arbianti ◽  
M Mariana ◽  
Nathania Dwi Karina ◽  
Vifki Leondo
Keyword(s):  
Wastewater Treatment ◽  
Fuel Cell ◽  
Microbial Fuel Cell ◽  
Mixed Culture ◽  
Biofilm Formation ◽  
Formation Time ◽  
Electricity Production ◽  
Gram Negative Bacteria ◽  
Treatment Unit ◽  
Gram Negative

Microbial Fuel Cell (MFC) technology is highly prospective to be developed because it could be utilized as the alternative electricity sources and simultaneously as the wastewater treatment unit using microorganism as catalyst. Industrial Tempe wastewater has the potential to be used as MFC substrate since it still contains high nutrition for microbe and could pollute the environment if it disposed before being processed first. This study focused on investigating the effect of selective mixed culture addition and biofilm formation on the electricity production and the wastewater treatment aspects with tubular single chamber membranless reactor and industrial Tempe wastewater substrate. The result showed that, with the addition of selective mixed culture, the optimum electricity production obtained with addition of 1 ml gram-negative bacteria with increase in electricity production up to 92.14% and average voltage of 17.91 mV, while the optimum decreased levels of COD and BOD obtained with addition of 5 ml gram-negative bacteria which are 29.32% and 51.32%. On the biofilm formation experiment, optimum electricity production obtained from biofilm formation time for 14 days with increase in electricity production up to 10-folds and average voltage of 30.52 mV, while the optimum decreased levels of COD and BOD obtained from biofilm formation time for 7 days which are 18.2% and 35.9%.Keywords : biofilm, Microbial Fuel Cell, selective mixed culture, Tempe wastewater, tubular reactor

Bacteriological Sampling of Telephones and Other Hospital Staff Hand-Contact Objects

1984 ◽  
Vol 5 (11) ◽  
pp. 533-535 ◽  
Author(s):  
Karen M. Rafferty ◽  
Stephen J. Pancoast
Keyword(s):  
General Hospital ◽  
Acute Care ◽  
Staff Member ◽  
Pathogenic Bacteria ◽  
Bacterial Contamination ◽  
Hospital Staff ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Gram Negative Organisms ◽  
Hand Contact

AbstractIn an acute-care general hospital, 114 telephones, intercoms, dictaphones, and bedpan flusher handles were sampled in patient-care areas for type of bacterial contamination. Nine of these (7%) demonstrated potentially pathogenic bacteria including Klebsiella, Enterobacter, Pseudomonas and Aeromonas. Inanimate, environmental, staff hand-contact objects were only lightly contaminated, did not represent a significant reservoir of gram-negative organisms, and therefore, would be unlikely to be a vehicle of transmission of gram-negative bacteria from the hands of one staff member to another under routine circumstances. Surveillance and disinfection of telephones and related hand-contact items in the hospital appear unnecessary.

Sign in / Sign up

Export Citation Format

Share Document