scholarly journals 660. Evaluation of Qvella’s FAST-Prep™ Liquid Colony™ for Early Antimicrobial Sensitivity Testing of Positive Blood Culture by Disk Diffusion Method

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S386-S386
Author(s):  
Susan M Novak-Weekley ◽  
Aye Aye Khine ◽  
Tino Alavie ◽  
Namidha Fernandez ◽  
Laxman Pandey ◽  
...  
Keyword(s):  
Direct Method ◽  
Viable Cell ◽  
Turnaround Time ◽  
Disk Diffusion ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Sensitivity Testing ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative

Abstract Background Conventional antimicrobial susceptibility testing (AST) of microorganisms from positive blood cultures (PBC) can take ≥ 2 days. In order to improve the turnaround time for AST on a PBC, CLSI and EUCAST have made efforts to standardize procedures for disk diffusion (DD) direct from a PBC. Qvella Corporation (Richmond Hill, ON, Canada) has recently developed FAST-Prep, an automated centrifugal sample preparation system that rapidly delivers a Liquid Colony consisting of a purified, concentrated, viable cell suspension directly from a PBC. This study was performed to investigate the feasibility of DD AST off of a PBC using a FAST-Prep Liquid Colony. Methods Contrived PBC samples were prepared by spiking 6 species of Gram-positive and 4 species of Gram-negative bacteria (3-5 strains per species) into FA® Plus bottles and incubating in the BACT/ALERT® VIRTUO® System (bioMerieux, Durham, NC). After positivity, 3 mL of PBC was added to the FAST-Prep cartridge. After 20 minutes of processing in the FAST-Prep instrument, the Liquid Colony was removed from the cartridge and a 0.5 McFarland sample was prepared for DD AST. In parallel, the DD AST from a PBC was performed using 4 drops of PBC (CLSI direct method). Both methods were compared to conventional colony-based DD AST. After 16-18 hours of incubation zone diameters and S/I/R interpretations were determined. Categorical agreement (CA) and errors for both DD AST methods were calculated. In addition, colony plate counting was performed on 0.5 McFarland suspensions of Liquid Colony and the plate colony to determine biomass recovery and sample purity. Results CA for a FAST-Prep DD AST for Gram-positive and Gram-negative bacteria was 95.6% and 98.6%, respectively, compared to CA for CLSI DD AST of 77.2% and 81.9%, respectively. Biomass in the Liquid Colony was 7.2x108 and 1.2x109 CFU for Gram-positive and Gram-negative bacteria, respectively. Cell concentration in the 0.5 McFarland suspension of the Liquid Colony was 3.7x107 and 5.9x107 CFU/mL for Gram-positive and Gram-negative bacteria, respectively, which was similar to the concentration for the reference colony suspension. Conclusion The results support the potential role of FAST-Prep in providing a Liquid Colony for use in rapid AST. Disclosures Susan M. Novak-Weekley, PhD, D(ABMM), Qvella (Employee, Shareholder) Aye Aye Khine, PhD, Qvella (Employee, Shareholder) Tino Alavie, PhD, Qvella (Employee) Namidha Fernandez, MS, Qvella (Employee) Laxman Pandey, MS, Qvella (Employee) Abdossamad Talebpour, PhD, Qvella (Employee, Shareholder)

scholarly journals Chemical Composition and Antibacterial Activity of the Essential Oil of Espeletia nana

2012 ◽  
Vol 7 (5) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Alexis Peña ◽  
Luis Rojas ◽  
Rosa Aparicio ◽  
Libia Alarcón ◽  
José Gregorio Baptista ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative ◽  
Gram Positive Bacteria

The essential oil of the leaves of Espeletia nana Cuatrec, obtained by hydrodistillation, was analyzed by GC-MS, which allowed the identification of 24 components, which made up 99.9% of the oil. The most abundant compounds were α-pinene (38.1%), β-pinene (17.2%), myrcene (15.0%), spathulenol (4.2%), bicyclogermacrene (4.0%), α-zingiberene (4.0%), and γhimachalene (3.7%). Antibacterial activity was tested against Gram-positive and Gram-negative bacteria using the agar disk diffusion method. Activity was observed only against Gram-positive bacteria. MIC values were determined for Staphylococcus aureus ATCC 25923(200 μg/mL) and Enterococcus faecalis ATCC 29212 (600 μg/mL).

scholarly journals Antimicrobial activity of methanol extracts of four Parmeliaceae lichen species

2013 ◽  
Vol 11 (1) ◽  
pp. 45-53 ◽  
Author(s):  
Igor Stojanovic ◽  
Niko Radulovic ◽  
Vladimir Cvetkovic ◽  
Tatjana Mitrovic ◽  
Slavisa Stamenkovic
Keyword(s):  
Antimicrobial Activity ◽  
Statistical Treatment ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative ◽  
Methanol Extracts ◽  
Group I ◽  
Distinguished Group

Antimicrobial activity of methanol extracts of four Parmeliaceae lichens (Hypogymnia physodes (L.) Nyl., Evernia prunastri (L.) Ach., Flavoparmelia caperata (L.) Hale and Parmelia sulcata Taylor) against a panel of microbial strains (11 Gram-positive (Enterococus sp., Bacillus subtilllis, Sarcina lutea, Micrococus luteus, Staphylococcus aureus, Clostridium sporogenes) and Gram-negative bacteria (Escherichia coli, Proteus vulgaris, Salmonela enteritidis, Pseudomonas aeruginosa, Klebsiella pneumoniae), the filamentous fungus A. niger and the yeast C. albicans) was assayed using a disk diffusion method (1 mg of the extract per disc; extracts were dissolved in methanol, 25 mg/mL). All tested extracts showed moderate antimicrobial activity. Multivariate statistical treatment (agglomerative hierarchical clustering analysis, AHC) of the obtained results allowed grouping of the samples according to their antimicrobial potential against different strains: antimicrobial profile of H. physodes and E. prunastri extracts were comparable; the similar is true for F. caperata and P. sulcata samples. In addition, based on the similarities/ dissimilarities in their susceptibility toward the tested extracts, two groups of microorganisms could be distinguished: Group I - P. vulgaris, K. pneumoniae (Gram-negative bacteria), A. niger and C. albicans; Group II - E. coli, S. enteritidis, P. aeruginosa (Gram-negative bacteria) and all of the assayed Gram-positive strains.

In vitro Antibacterial Activity of 7-Substituted-6-Fluoroquinolone and 7-Substituted-6,8-Difluoroquinolone Derivatives

Chemotherapy ◽  
2017 ◽  
Vol 62 (3) ◽  
pp. 194-198 ◽  
Author(s):  
Socorro Leyva-Ramos ◽  
Denisse de Loera ◽  
Jaime Cardoso-Ortiz
Keyword(s):  
Antibacterial Activity ◽  
Antimicrobial Agents ◽  
New Drugs ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Topoisomerase Iv ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative

Background: Fluoroquinolones are widely prescribed synthetic antimicrobial agents. Quinolones act by converting their targets, gyrase and topoisomerase IV, into toxic enzymes that fragment the bacterial chromosome; the irreversible DNA damage eventually causes the killing of bacteria. Thorough knowledge of the structure-activity relationship of quinolones is essential for the development of new drugs with improved activity against resistant strains. Methods: The compounds were screened for their antibacterial activity against 4 representing strains using the Kirby-Bauer disk diffusion method. Minimal inhibitory concentration (MIC) was determined by measuring the diameter of the inhibition zone using concentrations between 250 and 0.004 μg/mL. Results: MIC of derivatives 2, 3, and 4 showed potent antimicrobial activity against gram-positive and gram-negative bacteria. The effective concentrations were 0.860 μg/mL or lower. MIC for compounds 5-11 were between 120 and 515 μg/mL against Escherichia coli and Staphylococcus aureus, and substituted hydrazinoquinolones 7-10 showed poor antibacterial activity against gram-positive and gram-negative bacteria compared with other quinolones. Conclusion: Compounds obtained by modifications on C-7 of norfloxacin with the acetylated piperazinyl, halogen atoms, and substituted hydrazinyl showed good in vitro activity - some even better than the original compound.

scholarly journals Antimicrobial Sensitivity Testing Using the Kirby-Bauer Disk Diffusion Method; Limited Utility in Ugandan Hospitals

2020 ◽  
Author(s):  
Ivan Segawa ◽  
Kenneth Ssebambulidde ◽  
Daniel Kiiza ◽  
Jackson Mukonzo
Keyword(s):  
Action Plan ◽  
Antibiotic Consumption ◽  
Turnaround Time ◽  
World Health ◽  
Disk Diffusion ◽  
Diffusion Method ◽  
Sensitivity Testing ◽  
Disk Diffusion Method ◽  
Cross Sectional ◽  
Antimicrobial Sensitivity

Background: Antimicrobial resistance (AMR) is a global health threat responsible for increased healthcare costs and mortality. The World Health Organization (WHO) global action plan on AMR recommends antimicrobial sensitivity testing (AST) and surveillance of antibiotic use to address this threat. We conducted a cross-sectional study to determine the utility of AST in three major referral hospitals in Uganda. Methods: We used abstraction checklists to collect data on AST requests, AST performed, AST turnaround time, and dispensed antibiotics, from in-patient files and laboratory and pharmacy records. Antibiotic data were summarized using proportions. The relationship between dispensed antibiotics and AST antibiotic-disks was analyzed using spearman’s rank correlation and simple linear regression. Results: Of the 607 in-patient files reviewed, AST was requested in 24 (4.0%), and done in 13 (2.1%). All three hospitals used the Kirby-Bauer disk diffusion method for AST, with a median turnaround time of 5 days (IQR 4-8). While the frequently used AST antibiotic-disks were cotrimoxazole (13.0%), ampicillin (11.7%), and ceftriaxone (10.5%), the most dispensed antibiotics were metronidazole (30.3%), amoxicillin (19.6%) and ceftriaxone (14.8%). There was a weak correlation (r=0.313, p=0.120) between dispensed antibiotics and AST antibiotic-disks, and AST performance was not associated with antibiotic consumption. Conclusion: We report an underutilization of AST, inconsistent with the hospital antibiotic consumption, and may be related to the use of the disk diffusion method. We recommend alternative faster and better coordination in the procurement of AST diagnostics in Ugandan hospitals.

In-vitro Antioxidant and Antibacterial Activity of Methanolic Extract of Shorea robusta Gaertn. F. Resin

2016 ◽  
Vol 6 (4) ◽  
pp. 68
Author(s):  
Sushma Vashisht ◽  
Manish Pal Singh ◽  
Viney Chawla
Keyword(s):  
Antibacterial Activity ◽  
Methanolic Extract ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Disc Diffusion ◽  
Gram Positive ◽  
Gram Negative ◽  
Shorea Robusta ◽  
Dose Dependent ◽  
Resin Extract

The methanolic extract of the resin of Shorea robusta was subjected to investigate its antioxidant and antibacterial properties its utility in free radical mediated diseases including diabetic, cardiovascular, cancer etc. The methanol extract of the resin was tested for antioxidant activity using scavenging activity of DPPH (1,1-diphenyl-2-picrylhydrazil) radical method, reducing power by FeCl3 and antibacterial activity against gram positive and gram negative bacteria using disc diffusion method. The phytochemical screening considered the presence of triterpenoids, tannins and flavoniods. Overall, the plant extract is a source of natural antioxidants which might be helpful in preventing the progress of various oxidative stress mediated diseases including aging. The half inhibition concentration (IC50) of resin extract of Shorea robusta and ascorbic acid were 35.60 µg/ml and 31.91 µg/ml respectively. The resin extract exhibit a significant dose dependent inhibition of DPPH activity. Antibacterial activity was observed against gram positive and gram negative bacteria in dose dependent manner.Key Words: Shorea robusta, antioxidant, antibacterial, Disc-diffusion, DPPH.

Antibacterial activity of magnesium oxide nanoparticles prepared by Calcination method

2019 ◽  
Vol 10 (03) ◽  
Author(s):  
Elaf Ayad Kadhem ◽  
Miaad Hamzah Zghair ◽  
Sarah , Hussam H. Tizkam, Shoeb Alahmad Salih Mahdi ◽  
Hussam H. Tizkam ◽  
Shoeb Alahmad
Keyword(s):  
Antibacterial Activity ◽  
Magnesium Oxide ◽  
Diffusion Method ◽  
Oxide Nanoparticles ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Magnesium Oxide Nanoparticles ◽  
Agar Disc

magnesium oxide nanoparticles (MgO NPs) were prepared by simple wet chemical method using different calcination temperatures. The prepared NPs were characterized by Electrostatic Discharge (ESD), Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). It demonstrates sharp intensive peak with the increase of crystallinty and increase of the size with varying morphologies with respect to increase of calcination temperature. Antibacterial studies were done on gram negative bacteria (E.coli) and gram positive bacteria (S.aureus) by agar disc diffusion method. The zones of inhibitions were found larger for gram positive bacteria than gram negative bacteria, this mean, antibacterial MgO NPs activity more active on gram positive bacteria than gram negative bacteria because of the structural differences. It was found that antibacterial activity of MgO NPs was found it has directly proportional with their concentration.

scholarly journals Antibacterial, Antioxidant and Cytotoxic Properties of Crinum asiaticum Bulb Extract

2012 ◽  
Vol 28 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Md Atiar Rahman ◽  
Rumana Sharmin ◽  
Md Nazim Uddin ◽  
Md Sohel Rana ◽  
Nazim Uddin Ahmed
Keyword(s):  
Radical Scavenging ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Scavenging Effect ◽  
Ic50 Value ◽  
Radical Scavenging Effect ◽  
Dpph Scavenging ◽  
Crinum Asiaticum

Antibacterial effect of Crinum asiaticum bulb extract (1mg/disc) was tested on four Gram- positive and six Gram-negative bacteria by disc diffusion method using kanamycin (30 ìg/disc) as standard antibiotic disc. The bulb extract (250-1000mg/disc) showed significant zone of inhibition against all Gram-positive and Gram-negative bacteria ranging from 12-14 mm in diameter. Antioxidant potential of the same extract was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method. The extract showed remarkable free radical scavenging effect (95.96%) providing the IC50 value of 5.62 for the bulb extract and 5.46 for ascorbic acid (standard antioxidant) at the concentration of 1000 ìg/ml. The bulb extract was found to be (LC50 value 94.06 ?g/ml) in Brine-Shrimp lethality test. DOI: http://dx.doi.org/10.3329/bjm.v28i1.11801 Bangladesh J Microbiol, Volume 28, Number 1, June 2011, pp 1-5

Antimicrobial activity of Pycnarrhena cauliflora (Miers.) Diels. methanol extract

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Eti Nurwening Sholikhah ◽  
Maulina Diah ◽  
Mustofa ◽  
Masriani ◽  
Susi Iravati ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Methanolic Extract ◽  
Biological Activities ◽  
Positive Control ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Methanolic Extracts

Pycnarrhena cauliflora (Miers.) Diels., local name sengkubak, is one of indigenous plants from West Kalimantan that has been used as natural flavor. Pycnorrhena cauliflora is one of species of Menispermaceae family which is rich in bisbenzylisoquinoline alkaloids. This alkaloids are known to have various biological activities including antiprotozoal, antiplasmodial, antifungal and antibacterial activities. This study aimed to investigate antimicrobial activity of  the P. cauliflora (Miers.) Diels. methanolic extracts against gram-positive and gram-negative bacteria. The methanolic extract of P. cauliflora (Miers.) Diels., root, leaf and stem were prepared by maceration. The disk-diffusion method was then used to determine the antimicrobial activity of the extracts against Streptococcus pyogenes, S. mutants, Staphylococcus aureus, S. epidermidis, Salmonella typhi, Shigella flexneri, Pseudomonas aeruginosa and Escherichia coli after 18-24 h incubation at 37 oC. Amoxicillin was used as positive control for gram-positive bacteria and ciprofloxacin was used as gram-negative bacteria. The inhibition zones were then measured in mm. Analysis were conducted in duplicates. The results showed in general the methanolic extracts of P. cauliflora (Miers.) Diels. root (inhibition zone diameter= 10-23 mm) were more active than that leaf (0-15 mm) and stem (0-17 mm) extracts against gram-positive bacteria. The zone inhibition diameter of amoxicillin as positive control was 8-42 mm. In addition, the methanolic extracts of P. cauliflora (Miers.) Diels. root (12-17 mm) were also more active than that leaf (0-12 mm) and stem (0-12 mm) extracts against gram-negative bacteria. The zone inhibition diameter of ciprofloxacin as positive control was 33-36 mm. In conclusion, the methanolic extract of P. caulifloria (Miers.) Diels. root is the most extract active against both gram-positive and gram-negative bacteria. Further study will be focused to isolate active compounds in the methanolic extract of the root.

scholarly journals Antibacterial Activity and Flavonoids Content of Artemisia cina Berg. ex Poljakov Ethyl Acetate Extracts

2021 ◽  
Vol 13 (1) ◽  
pp. 106-112
Author(s):  
Sri Kasmiyati ◽  
Elizabeth Betty Elok Kristiani ◽  
Maria Marina Herawati ◽  
Andreas Binar Aji Sukmana
Keyword(s):  
Antibacterial Activity ◽  
Medicinal Plant ◽  
Ethyl Acetate ◽  
Biological Activities ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Flavonoid Content ◽  
Gram Positive ◽  
Gram Negative ◽  
Significant Difference

The medicinal plant-derived bioactive compounds have a potential for many biological activities, including antimicrobial activity. Artemisia cina is a medicinal plant from the Compositae family with the potential of having antitumor, antifungal, and antibacterial activity. This study aimed to determine the antibacterial activity and the flavonoid content of A. Cina’s ethyl acetate extract. Plants samples were extracted by ethyl acetate maceration method. Antibacterial activity was tested against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) by a disk diffusion method using 25, 50, and 100 mg/l extract concentrations. The flavonoid contents (quercetin and kaempferol) were measured using High-Performance Liquid Chromatography. The extracts of diploid and polyploid A. cina displayed some antibacterial activity, with the Gram-negative bacteria being more resistant than the Gram-positive counterpart. However, no significant difference was observed between the diploid and polyploid extracts. As for the flavonoid content, the highest quercetin content (0.5501 mg/ml) was found in the polyploid A. cina (J), while the highest kaempferol content (0.5818 mg/ml) was observed in the diploid A. cina (KJT). Although A. cina is widely grown in Indonesia, compared to other Artemisia species, A. cina has not been widely studied, especially its antibacterial  potential and in related to its flavonoid content and the use of ethyl acetate as the extraction solvent.  This study reveals the potential of A. cina as a natural antibacterial agent. 

scholarly journals The Efficacy of Psidium guajava Linn Leaf Extractsfrom Selangor Region Against Gram-Positive and Gram-Negative Bacteria

2018 ◽  
Vol 54 (4) ◽  
pp. 294
Author(s):  
S Zuhaira ◽  
Noorhaniz Mohd Nizam ◽  
PM Ridzuan
Keyword(s):  
Methanol Extract ◽  
Psidium Guajava ◽  
Diffusion Method ◽  
Future Research ◽  
Phytochemical Analysis ◽  
Gram Negative Bacteria ◽  
Leaf Extracts ◽  
Gram Positive ◽  
Gram Negative ◽  
Freeze Dried

Antibiotic is a type of medication that helps in fighting bacterial infection. Treating bacterial infections in clinical setting become more complicated and costly due to drug resistance. This study was conducted to determine the antibacterial potential of Psidium guajava Linn leaf extracts against Gram-positive and Gram-negative bacteria. P. guajava Linn leaf was obtained from Research Orchards at University Putra Malaysia (UPM). Leaves were extracted using three types of extracts; hot, cold and methanol extract. Freeze dried was used in this study and temperature was set at -104°C for 24 hours. Antibacterial testing was determined using disc diffusion and well diffusion method. Antibacterial activity was evaluated by measuring the inhibitory zone of the tested bacteria. Phytochemical analysis was conducted by adding few drop of diluted NaOH (Sodium Hydroxide) solution to detect the active flavanoid from leaves extract. Antimicrobial activity showed all extracts were effective against Gram-positive and Gram-negative bacteria. Phytochemical analysis of P. guajava Linn leaf extracts showed the methanol extract indicating the presence of tannins, phenols, flavonoids, terpenoids, glycosides and saponins. Results showed that P. guajava Linn leaf was effective against Gram-positive and Gram-negative bacteria, and pythochemical analysis also exhibited a few active compounds that were determined. P. guajava Linn leaf had potential natural product that may be used for further analysis in the future research.

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