scholarly journals The Effect of Antibiotics on Planktonic Cells and Biofilm Formation Ability of Collected Arcobacter-like Strains and Strains Isolated within the Czech Republic

Antibiotics ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 87
Author(s):  
Karolína Švarcová ◽  
Marcela Pejchalová ◽  
David Šilha
Keyword(s):  
Biofilm Formation ◽  
Planktonic Cells ◽  
High Susceptibility ◽  
The Czech Republic ◽  
Microdilution Method ◽  
Resistant Strains ◽  
In Vitro Effects ◽  
High Level ◽  
Biofilm Structure

The purpose of this study was to test the in vitro effects of ampicillin, ciprofloxacin, clindamycin, erythromycin, gentamicin, and tetracycline on planktonic cells of Arcobacter-like microorganisms and on their biofilm formation ability. The minimum inhibitory concentrations (MICs) were determined by the microdilution method. Further, biofilm formation ability in the presence of various concentrations of antibiotics was evaluated by a modified Christensen method. Most of the 60 strains exhibited high susceptibility to gentamicin (98.3%), ciprofloxacin (95.0%), and erythromycin (100.0%). High level of resistance was observed to clindamycin and tetracycline with MIC50 and MIC90 in range of 4–32 mg/L and 32–128 mg/L, respectively. Combined resistance to both clindamycin and tetracycline was found in 38.3% of tested strains. In general, higher biofilm formation was observed especially at lower concentrations of antibiotics (0.13–2 mg/L). However, a significant decrease in biofilm formation ability of Pseudarcobacter defluvii LMG 25694 was exhibited with ampicillin and clindamycin at concentrations above 32 or 8 mg/L, respectively. Biofilm formation represents a potential danger of infection and also a risk to human health, in particular due to antimicrobial-resistant strains and the ability to form a biofilm structure at a concentration that is approximately the MIC determined for planktonic cells.

scholarly journals In VitroAnalyses of the Effects of Heparin and Parabens on Candida albicans Biofilms and Planktonic Cells

2011 ◽  
Vol 56 (1) ◽  
pp. 148-153 ◽  
Author(s):  
Marisa H. Miceli ◽  
Stella M. Bernardo ◽  
T. S. Neil Ku ◽  
Carla Walraven ◽  
Samuel A. Lee
Keyword(s):  
Candida Albicans ◽  
Metabolic Activity ◽  
Biofilm Formation ◽  
High Dose ◽  
Dependent Manner ◽  
Planktonic Cells ◽  
Content Type ◽  
Heparin Sodium ◽  
The Individual

ABSTRACTInfections and thromboses are the most common complications associated with central venous catheters. Suggested strategies for prevention and management of these complications include the use of heparin-coated catheters, heparin locks, and antimicrobial lock therapy. However, the effects of heparin onCandida albicansbiofilms and planktonic cells have not been previously studied. Therefore, we sought to determine thein vitroeffect of a heparin sodium preparation (HP) on biofilms and planktonic cells ofC. albicans. Because HP contains two preservatives, methyl paraben (MP) and propyl paraben (PP), these compounds and heparin sodium without preservatives (Pure-H) were also tested individually. The metabolic activity of the mature biofilm after treatment was assessed using XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction and microscopy. Pure-H, MP, and PP caused up to 75, 85, and 60% reductions of metabolic activity of the mature preformedC. albicansbiofilms, respectively. Maximal efficacy against the mature biofilm was observed with HP (up to 90%) compared to the individual compounds (P< 0.0001). Pure-H, MP, and PP each inhibitedC. albicansbiofilm formation up to 90%. A complete inhibition of biofilm formation was observed with HP at 5,000 U/ml and higher. When tested against planktonic cells, each compound inhibited growth in a dose-dependent manner. These data indicated that HP, MP, PP, and Pure-H havein vitroantifungal activity againstC. albicansmature biofilms, formation of biofilms, and planktonic cells. Investigation of high-dose heparin-based strategies (e.g., heparin locks) in combination with traditional antifungal agents for the treatment and/or prevention ofC. albicansbiofilms is warranted.

scholarly journals Biofilm Formation by Stenotrophomonas maltophilia: Modulation by Quinolones, Trimethoprim-Sulfamethoxazole, and Ceftazidime

2004 ◽  
Vol 48 (1) ◽  
pp. 151-160 ◽  
Author(s):  
Giovanni Di Bonaventura ◽  
Ilaria Spedicato ◽  
Domenico D'Antonio ◽  
Iole Robuffo ◽  
Raffaele Piccolomini
Keyword(s):  
Cell Viability ◽  
Biofilm Formation ◽  
Stenotrophomonas Maltophilia ◽  
Maximum Growth ◽  
Total Biomass ◽  
Significant Activity ◽  
Original Mass ◽  
In Vitro Effects ◽  
Over Time

ABSTRACT We investigated the in vitro effects of seven fluoroquinolones (ciprofloxacin, grepafloxacin, levofloxacin, moxifloxacin, norfloxacin, ofloxacin, and rufloxacin), compared to those of trimethoprim-sulfamethoxazole (SXT) and ceftazidime on total biomass and cell viability of Stenotrophomonas maltophilia biofilm. S. maltophilia attached rapidly to polystyrene, within 2 h of incubation, and then biofilm formation increased over time, reaching maximum growth at 24 h. In the presence of fluoroquinolones at one-half and one-fourth the MIC, biofilm biomass was significantly (P < 0.01) reduced to 55 to 70% and 66 to 76% of original mass, respectively. Ceftazidime and SXT did not exert any activity. Biofilm bacterial viability was significantly reduced by all antibiotics tested at one-half the MIC. At one-fourth the MIC all antibiotics, except levofloxacin, significantly reduced viability. Treatment of preformed biofilms with bactericidal concentrations (500, 100, and 50 μg/ml) of all fluoroquinolones caused, except for norfloxacin, significant reduction of biofilm biomass to 29.5 to 78.8, 64.1 to 83.6, and 70.5 to 82.8% of original mass, respectively. SXT exerted significant activity at 500 μg/ml only. Ceftazidime was completely inactive. Rufloxacin exhibited the highest activity on preformed biofilm viability, significantly decreasing viable counts by 0.6, 5.4, and 17.1% at 500, 100, and 50 μg/ml, respectively. Our results show that (i) subinhibitory (one-half and one-fourth the MIC) concentrations of fluoroquinolones inhibit adherence of S. maltophilia to polystyrene and (ii) clinically achievable concentrations (50 and 100 μg/ml) of rufloxacin are able to eradicate preformed S. maltophilia biofilm.

Inhibitory activity of isoniazid and ethionamide against Cryptococcus biofilms

2015 ◽  
Vol 61 (11) ◽  
pp. 827-836 ◽  
Author(s):  
Rossana de Aguiar Cordeiro ◽  
Rosana Serpa ◽  
Francisca Jakelyne de Farias Marques ◽  
Charlline Vládia Silva de Melo ◽  
Antonio José de Jesus Evangelista ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Biofilm Formation ◽  
Inhibitory Effect ◽  
Cell Membrane Permeability ◽  
Planktonic Cells ◽  
Fungal Cell ◽  
Antituberculosis Drugs ◽  
Opportunistic Mycoses ◽  
Cryptococcus Spp

In recent years, the search for drugs to treat systemic and opportunistic mycoses has attracted great interest from the scientific community. This study evaluated the in vitro inhibitory effect of the antituberculosis drugs isoniazid and ethionamide alone and combined with itraconazole and fluconazole against biofilms of Cryptococcus neoformans and Cryptococcus gattii. Antimicrobials were tested at defined concentrations after susceptibility assays with Cryptococcus planktonic cells. In addition, we investigated the synergistic interaction of antituberculosis drugs and azole derivatives against Cryptococcus planktonic cells, as well as the influence of isoniazid and ethionamide on ergosterol content and cell membrane permeability. Isoniazid and ethionamide inhibited both biofilm formation and viability of mature biofilms. Combinations formed by antituberculosis drugs and azoles proved synergic against both planktonic and sessile cells, showing an ability to reduce Cryptococcus biofilms by approximately 50%. Furthermore, isoniazid and ethionamide reduced the content of ergosterol in Cryptococcus spp. planktonic cells and destabilized or permeabilized the fungal cell membrane, leading to leakage of macromolecules. Owing to the paucity of drugs able to inhibit Cryptococcus biofilms, we believe that the results presented here might be of interest in the designing of new antifungal compounds.

scholarly journals In vitro effects of N-acetylcysteine alone and combined with tigecycline on planktonic cells and biofilms of Acinetobacter baumannii

2018 ◽  
Vol 10 (1) ◽  
pp. 212-218 ◽  
Author(s):  
Jinlun Feng ◽  
Baomo Liu ◽  
Junwen Xu ◽  
Qinqin Wang ◽  
Lixia Huang ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Planktonic Cells ◽  
In Vitro Effects

scholarly journals Antibiotic Susceptibility of Escherichia coli Cells during Early-Stage Biofilm Formation

2019 ◽  
Vol 201 (18) ◽  
Author(s):  
Huan Gu ◽  
Sang Won Lee ◽  
Joseph Carnicelli ◽  
Zhaowei Jiang ◽  
Dacheng Ren
Keyword(s):  
Antibiotic Susceptibility ◽  
Biofilm Formation ◽  
Life Form ◽  
Early Stage ◽  
Dynamic Change ◽  
Cell Interactions ◽  
Planktonic Cells ◽  
Content Type ◽  
High Level ◽  
Cell Cell

ABSTRACT Bacteria form complex multicellular structures on solid surfaces known as biofilms, which allow them to survive in harsh environments. A hallmark characteristic of mature biofilms is the high-level antibiotic tolerance (up to 1,000 times) compared with that of planktonic cells. Here, we report our new findings that biofilm cells are not always more tolerant to antibiotics than planktonic cells in the same culture. Specifically, Escherichia coli RP437 exhibited a dynamic change in antibiotic susceptibility during its early-stage biofilm formation. This phenomenon was not strain specific. Upon initial attachment, surface-associated cells became more sensitive to antibiotics than planktonic cells. By controlling the cell adhesion and cluster size using patterned E. coli biofilms, cells involved in the interaction between cell clusters during microcolony formation were found to be more susceptible to ampicillin than cells within clusters, suggesting a role of cell-cell interactions in biofilm-associated antibiotic tolerance. After this stage, biofilm cells became less susceptible to ampicillin and ofloxacin than planktonic cells. However, when the cells were detached by sonication, both antibiotics were more effective in killing the detached biofilm cells than the planktonic cells. Collectively, these results indicate that biofilm formation involves active cellular activities in adaption to the attached life form and interactions between cell clusters to build the complex structure of a biofilm, which can render these cells more susceptible to antibiotics. These findings shed new light on bacterial antibiotic susceptibility during biofilm formation and can guide the design of better antifouling surfaces, e.g., those with micron-scale topographic structures to interrupt cell-cell interactions. IMPORTANCE Mature biofilms are known for their high-level tolerance to antibiotics; however, antibiotic susceptibility of sessile cells during early-stage biofilm formation is not well understood. In this study, we aim to fill this knowledge gap by following bacterial antibiotic susceptibility during early-stage biofilm formation. We found that the attached cells have a dynamic change in antibiotic susceptibility, and during certain phases, they can be more sensitive to antibiotics than planktonic counterparts in the same culture. Using surface chemistry-controlled patterned biofilm formation, cell-surface and cell-cell interactions were found to affect the antibiotic susceptibility of attached cells. Collectively, these findings provide new insights into biofilm physiology and reveal how adaptation to the attached life form may influence antibiotic susceptibility of bacterial cells.

scholarly journals In vitro activity of the trinem sanfetrinem (GV104326) against gram-positive organisms.

1996 ◽  
Vol 40 (9) ◽  
pp. 2142-2146 ◽  
Author(s):  
K V Singh ◽  
T M Coque ◽  
B E Murray
Keyword(s):  
Staphylococcus Aureus ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Gentamicin Resistance ◽  
High Level

The in vitro activity of the trinem sanfetrinem (formerly GV104326) (GV) was compared with that of vancomycin, ampicillin, and/or nafcillin against 287 gram-positive bacteria, including methicillin-resistant Staphylococcus aureus and multiresistant enterococci, by the agar and microbroth dilution methods. GV demonstrated 2 to 16 times more activity than ampicillin and nafcillin against the majority of these organisms. The MIC range of GV was 16 to 64 micrograms/ml for 19 Enterococcus faecium strains that were highly resistant to ampicillin (ampicillin MIC range, 64 to 512 micrograms/ml) and vancomycin resistant and 0.25 to 32 micrograms/ml for resistant Rhodococcus spp. Similar activities (+/-1 dilution) were observed by either the agar or the broth microdilution method. GV demonstrated bactericidal activity against a beta-lactamase-producing Enterococcus faecalis strain and against two methicillin-susceptible Staphylococcus aureus strains in 10(5)-CFU/ml inocula. Synergy between GV and gentamicin was observed against an E. faecalis strain that lacked high-level gentamicin resistance. The activity of GV suggests this compound warrants further study.

Rosemary and Tea Tree Essential Oils Exert Antibiofilm Activities In Vitro against Staphylococcus aureus and Escherichia coli

2020 ◽  
Vol 83 (7) ◽  
pp. 1261-1267
Author(s):  
TING LIU ◽  
JINGFAN WANG ◽  
XIAOMAN GONG ◽  
XIAOXIA WU ◽  
LIU LIU ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Essential Oil ◽  
Biofilm Formation ◽  
Gas Chromatography Mass Spectrometry ◽  
Tea Tree ◽  
E Coli ◽  
Microdilution Method ◽  
Broth Microdilution Method

ABSTRACT The purpose of the present study was to determine the bioactive compounds in rosemary essential oil (REO) and tea tree essential oil (TEO) and to investigate their antibacterial and antibiofilm activities against Staphylococcus aureus and Escherichia coli in vitro. The MIC and MBC assays were performed to assess the antibacterial activity of these two EOs against S. aureus and E. coli with the broth microdilution method. A crystal violet assay was used to ascertain the effects of EOs on the biofilm formation of the test strains, and a tetrazolium bromide (MTT) assay was used to measure the level of inactivation of mature biofilms by EOs. Gas chromatography–mass spectrometry revealed 15 compounds in REO and 27 compounds in TEO, representing 97.78 and 98.13% of the total EO, respectively. Eucalyptol and α-pinene were found in high concentrations in REO, and the two major compounds in TEO were 4-terpineol and terpinolene. The MICs of REO for the two S. aureus and E. coli test strains were both 0.5 mg/mL, and the MICs of TEO for the two strains were both 0.25 mg/mL. Therefore, these EOs can significantly inhibit the formation of biofilms and induced morphological biofilm changes, as verified by scanning electron microscopy. Both EOs had destructive effects on the mature biofilm of the two test strains. TEO was more inhibitory than REO for biofilm formation by the two test strains. HIGHLIGHTS

scholarly journals In Vitro Activities of RWJ-54428 (MC-02,479) against Multiresistant Gram-Positive Bacteria

2001 ◽  
Vol 45 (5) ◽  
pp. 1422-1430 ◽  
Author(s):  
Suzanne Chamberland ◽  
Johanne Blais ◽  
Monica Hoang ◽  
Cynthia Dinh ◽  
Dylan Cotter ◽  
...  
Keyword(s):  
Multidrug Resistant ◽  
Penicillin G ◽  
Significant Activity ◽  
Coagulase Negative Staphylococci ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Level Of Activity ◽  
Resistant Strains ◽  
High Level

ABSTRACT RWJ-54428 (MC-02,479) is a new cephalosporin with a high level of activity against gram-positive bacteria. In a broth microdilution susceptibility test against methicillin-resistant Staphylococcus aureus (MRSA), RWJ-54428 was as active as vancomycin, with an MIC at which 90% of isolates are inhibited (MIC90) of 2 μg/ml. For coagulase-negative staphylococci, RWJ-54428 was 32 times more active than imipenem, with an MIC90 of 2 μg/ml. RWJ-54428 was active against S. aureus, Staphylococcus epidermidis, and Staphylococcus haemolyticus isolates with reduced susceptibility to glycopeptides (RWJ-54428 MIC range, ≤0.0625 to 1 μg/ml). RWJ-54428 was eight times more potent than methicillin and cefotaxime against methicillin-susceptible S. aureus (MIC90, 0.5 μg/ml). For ampicillin-susceptible Enterococcus faecalis (including vancomycin-resistant and high-level aminoglycoside-resistant strains), RWJ-54428 had an MIC90 of 0.125 μg/ml. RWJ-54428 was also active against Enterococcus faecium, including vancomycin-, gentamicin-, and ciprofloxacin-resistant strains. The potency against enterococci correlated with ampicillin susceptibility; RWJ-54428 MICs ranged between ≤0.0625 and 1 μg/ml for ampicillin-susceptible strains and 0.125 and 8 μg/ml for ampicillin-resistant strains. RWJ-54428 was more active than penicillin G and cefotaxime against penicillin-resistant, -intermediate, and -susceptible strains ofStreptococcus pneumoniae (MIC90s, 0.25, 0.125, and ≤0.0625 μg/ml, respectively). RWJ-54428 was only marginally active against most gram-negative bacteria; however, significant activity was observed against Haemophilus influenzae andMoraxella catarrhalis (MIC90s, 0.25 and 0.5 μg/ml, respectively). This survey of the susceptibilities of more than 1,000 multidrug-resistant gram-positive isolates to RWJ-54428 indicates that this new cephalosporin has the potential to be useful in the treatment of infections due to gram-positive bacteria, including strains resistant to currently available antimicrobials.

scholarly journals Emergence of Penicillin-ResistantStreptococcus Pneumoniaein Southern Ontario, 1993–94

1995 ◽  
Vol 6 (3) ◽  
pp. 157-160 ◽  
Author(s):  
Andrew E Simor ◽  
Anita Rachlis ◽  
Lisa Louie ◽  
Janet Goodfellow ◽  
Marie Louie
Keyword(s):  
Antimicrobial Agents ◽  
Clinical Laboratory ◽  
Tertiary Care ◽  
National Committee ◽  
In Vitro Susceptibility ◽  
Southern Ontario ◽  
Recent Emergence ◽  
Resistant Strains ◽  
High Level

Objective: To determine the prevalence of resistance ofStreptococcus pneumoniaeto penicillin and other antimicrobial agents in metropolitan Toronto.Design: Consecutive pneumococcal isolates from different patients were obtained from two private community-based laboratories and from patients assessed in the emergency department of a tertiary-care teaching hospital in Toronto, Ontario between June and December 1993, and between March and October 1994. In vitro susceptibility testing was done by broth microdilution in accordance with National Committee for Clinical Laboratory Standards guidelines.Results: Twenty (7.3±3.1%) of 274 pneumococcal isolates were resistant to penicillin; six (30%) isolates had high-level resistance (minimal inhibitory concentration [mic] 2.0 μg/mL or greater); and 14 isolates had intermediate resistance (mic0.1 to 1.0 μg/mL). Penicillin-resistant strains were also frequently resistant to tetracycline (55%), cotrimoxazole (50%), erythromycin (40%) and cefuroxime (35%). Resistant strains comprised several serotypes: 19F (six isolates), 9V (three), 23F (three), and one each of 6A, 6B, 14, and 19A; four isolates were nontypeable.Conclusions: There has been a recent emergence of penicillin-resistantS pneumoniaein southern Ontario. National and regional surveillance is warranted to determine the extent of the problem elsewhere in Canada.

scholarly journals Inhibitory Effects of Lactoferrin on Growth and Biofilm Formation of Porphyromonas gingivalis and Prevotella intermedia

2009 ◽  
Vol 53 (8) ◽  
pp. 3308-3316 ◽  
Author(s):  
Hiroyuki Wakabayashi ◽  
Koji Yamauchi ◽  
Tetsuo Kobayashi ◽  
Tomoko Yaeshima ◽  
Keiji Iwatsuki ◽  
...  
Keyword(s):  
Porphyromonas Gingivalis ◽  
Biofilm Formation ◽  
Periodontal Diseases ◽  
Antimicrobial Protein ◽  
Antibiofilm Activity ◽  
Prevotella Intermedia ◽  
Periodontopathic Bacteria ◽  
Oral Pathogens ◽  
In Vitro Effects

ABSTRACT Lactoferrin (LF) is an iron-binding antimicrobial protein present in saliva and gingival crevicular fluids, and it is possibly associated with host defense against oral pathogens, including periodontopathic bacteria. In the present study, we evaluated the in vitro effects of LF-related agents on the growth and biofilm formation of two periodontopathic bacteria, Porphyromonas gingivalis and Prevotella intermedia, which reside as biofilms in the subgingival plaque. The planktonic growth of P. gingivalis and P. intermedia was suppressed for up to 5 h by incubation with ≥130 μg/ml of human LF (hLF), iron-free and iron-saturated bovine LF (apo-bLF and holo-bLF, respectively), and ≥6 μg/ml of bLF-derived antimicrobial peptide lactoferricin B (LFcin B); but those effects were weak after 8 h. The biofilm formation of P. gingivalis and P. intermedia over 24 h was effectively inhibited by lower concentrations (≥8 μg/ml) of various iron-bound forms (the apo, native, and holo forms) of bLF and hLF but not LFcin B. A preformed biofilm of P. gingivalis and P. intermedia was also reduced by incubation with various iron-bound bLFs, hLF, and LFcin B for 5 h. In an examination of the effectiveness of native bLF when it was used in combination with four antibiotics, it was found that treatment with ciprofloxacin, clarithromycin, and minocycline in combination with native bLF for 24 h reduced the amount of a preformed biofilm of P. gingivalis compared with the level of reduction achieved with each agent alone. These results demonstrate the antibiofilm activity of LF with lower iron dependency against P. gingivalis and P. intermedia and the potential usefulness of LF for the prevention and treatment of periodontal diseases and as adjunct therapy for periodontal diseases.

Sign in / Sign up

Export Citation Format

Share Document