scholarly journals Enhancing the fungicidal activity of amphotericin B via vacuole disruption by benzyl isothiocyanate, a cruciferous plant constituent

2020 ◽  
Author(s):  
N. Yamada ◽  
W. Murata ◽  
Y. Yamaguchi ◽  
K.‐I. Fujita ◽  
A. Ogita ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Fungicidal Activity ◽  
Benzyl Isothiocyanate ◽  
Plant Constituent ◽  
Cruciferous Plant

Stable Phenotypic Resistance of CandidaSpecies to Amphotericin B Conferred by Preexposure to Subinhibitory Levels of Azoles

1998 ◽  
Vol 36 (9) ◽  
pp. 2690-2695 ◽  
Author(s):  
Jose A. Vazquez ◽  
Maria T. Arganoza ◽  
Dina Boikov ◽  
Stephanie Yoon ◽  
Jack D. Sobel ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Clinical Setting ◽  
Fungicidal Activity ◽  
No Reduction ◽  
Growth Conditions ◽  
In Vitro Assays ◽  
In Vitro Susceptibility ◽  
Phenotypic Resistance ◽  
Time Period

The fungicidal activity of amphotericin B (AmB) was quantitated for several Candida species. Candida albicans andC. tropicalis were consistently susceptible to AmB, with less than 1% survivors after 6 h of exposure to AmB. C. parapsilosis and variants of C. lusitaniae andC. guilliermondii were the most resistant, demonstrating 50 to 90% survivors in this time period and as high as 1% survival after a 24-h exposure time. All Candida species were killed (<1% survivors) after 24 h of exposure to AmB. In contrast, overnight exposure to either fluconazole or itraconazole resulted in pronounced increases in resistance to subsequent exposures to AmB. Most dramatically, C. albicans was able to grow in AmB cultures after azole preexposure. Several other Candida species did not grow in AmB but showed little or no reduction in viability after up to 24 h in AmB. Depending on the growth conditions,Candida cells preexposed to azoles may retain AmB resistance for days after the azoles have been removed. If this in vitro antagonism applies to the clinical setting, treatment of patients with certain antifungal combinations may not be beneficial. The ability of some Candida isolates to survive transient exposures to AmB was not reflected in the in vitro susceptibility changes as measured by standard MIC assays. This finding should be considered in studies attempting to correlate patient outcome with in vitro susceptibilities of clinical fungal isolates. Patients who fail to respond to AmB may be infected with isolates that are classified as susceptible by standard in vitro assays but that may be resistant to transient antifungal exposures which may be more relevant in the clinical setting.

scholarly journals Assessment of Candida auris Response to Antifungal Drugs Using Time–Kill Assays and an Animal Model

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S73-S73 ◽  
Author(s):  
Ronen Ben-Ami ◽  
Liat Ashkenazi ◽  
Judith Berman ◽  
Nuphar Korolker ◽  
Anna Novikov
Keyword(s):  
Amphotericin B ◽  
Fungicidal Activity ◽  
Antifungal Drugs ◽  
Rank Test ◽  
Infection Model ◽  
Candida Auris ◽  
Fungistatic Activity ◽  
Kill Curve ◽  
Time Kill

Abstract Background Candida auris is an emerging nosocomial pathogen that is resistant to Fluconazole and variably susceptible to other systemic drug classes. Treatment with echinocandins has been recommended based on MICs in the susceptible range, but supporting in vivo data is lacking. Methods We tested the MIC of C. auris strains (n = 12) to fluconazole, voriconazole, posaconazole. anidulafungin, amphotericin B and flucytosine. Representative C. auris strains from Israel and South Africa, and a reference C. albicans strain were analysed using time–kill curve assays. Fungicidal activity was defined as reduction of ≥3 log from baseline CFU/ml. Response to caspofungin treatment was assessed in BALB/c mice immunosuppressed with cyclophosphamide and inoculated with 7 × 107C. auris cells by tail vein injection. Mice were treated from day +1 to day +7 with caspofungin (IP) at doses of 1 or 5 mg/kg and compared with sham-treated controls. Survival was assessed daily. Kaplan-Meier survival analyses were performed and treatment arms were compared using the log-rank test. Results Drug susceptibility results (MIC50 and MIC90) were: fluconazole, 64 and 128 mg/l; voriconazole, 0.5 and 24 mg/l; posaconazole, 0.5 and 27 mg/l; anidulafungin, 0.03 and 0.06 mg/l; amphotericin B, 2 and 8 mg/l; flucytosine, 0.3 and 1 mg/l. Time–kill curve analyses showed log reduction from baseline CFU concentration of −3.0 to −2.8 for fluconazole (MIC ×1), 5.6–6.1 for amphotericin B (MIC ×4) and −0.4 to −0.9 for caspofungin (MIC ×16), consistent with fungicidal activity of amphotericin B and weak fungistatic activity of caspofungin. In the mouse model, survival rate was similar with sham treatment (33%) and treatment with caspofungin 1 mg/kg/day (44%) and 5 mg/kg/day (22%), P = 0.7. Conclusion Despite generally low MIC, caspofungin has only mild fungistatic activity on C. auris and no effect on survival in a mouse infection model. Amphotericin B has fungicidal activity against C. auris. Disclosures All authors: No reported disclosures.

A comparison of the fungicidal activity of amphotericin B and posaconazole against Zygomycetes in vitro

2009 ◽  
Vol 63 (4) ◽  
pp. 361-364 ◽  
Author(s):  
Suganthini Krishnan-Natesan ◽  
Elias K. Manavathu ◽  
George J. Alangaden ◽  
Pranatharthi H. Chandrasekar
Keyword(s):  
Amphotericin B ◽  
Fungicidal Activity

Enhancement of the Fungicidal Activity of Amphotericin B by Allicin: Effects on Intracellular Ergosterol Trafficking

Planta Medica ◽  
2008 ◽  
Vol 75 (03) ◽  
pp. 222-226 ◽  
Author(s):  
Akira Ogita ◽  
Ken-ichi Fujita ◽  
Toshio Tanaka
Keyword(s):  
Amphotericin B ◽  
Fungicidal Activity

scholarly journals In Vitro Activity of a New Polyene, SPA-S-843, against Yeasts

1998 ◽  
Vol 42 (11) ◽  
pp. 3012-3013 ◽  
Author(s):  
C. Rimaroli ◽  
T. Bruzzese
Keyword(s):  
Candida Albicans ◽  
Amphotericin B ◽  
Candida Tropicalis ◽  
Candida Glabrata ◽  
Fungicidal Activity ◽  
Candida Krusei ◽  
Water Soluble ◽  
Vitro Activity ◽  
In Vitro Activity

ABSTRACT The in vitro activity of a new water-soluble polyene, SPA-S-843, was evaluated against 116 strains of Candida,Cryptococcus, and Saccharomyces spp. and compared with that of amphotericin B. SPA-S-843 demonstrated better inhibitory activity against all of the yeasts examined and better fungicidal activity against Candida albicans, Candida glabrata, Candida krusei, and Candida tropicalis than did amphotericin B.

scholarly journals Antifungal pharmacodynamic characteristics of fluconazole and amphotericin B tested against Candida albicans.

1997 ◽  
Vol 41 (6) ◽  
pp. 1392-1395 ◽  
Author(s):  
M E Klepser ◽  
E J Wolfe ◽  
R N Jones ◽  
C H Nightingale ◽  
M A Pfaller
Keyword(s):  
Candida Albicans ◽  
Amphotericin B ◽  
Fungicidal Activity ◽  
Narrow Range ◽  
Growth Effects ◽  
Fungistatic Activity ◽  
Time Kill

Time-kill curves were determined for three isolates of Candida albicans tested against fluconazole and amphotericin B at multiples of the MIC. Fluconazole produced fungistatic activity, with concentration-related growth effects observed over a narrow range of concentrations. Amphotericin B exhibited fungicidal activity, with enhancement of activity over a broader range of concentrations.

Visualization analysis of the vacuole-targeting fungicidal activity of amphotericin B against the parent strain and an ergosterol-less mutant of Saccharomyces cerevisiae

Microbiology ◽  
2013 ◽  
Vol 159 (Pt_5) ◽  
pp. 939-947 ◽  
Author(s):  
Chang-Kyung Kang ◽  
Keiichi Yamada ◽  
Yoshinosuke Usuki ◽  
Akira Ogita ◽  
Ken-ichi Fujita ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amphotericin B ◽  
Parent Strain ◽  
Fungicidal Activity ◽  
Visualization Analysis

scholarly journals Comparison of the Fungicidal Activities of Caspofungin and Amphotericin B against Candida glabrata

2005 ◽  
Vol 49 (12) ◽  
pp. 4989-4992 ◽  
Author(s):  
Francesco Barchiesi ◽  
Elisabetta Spreghini ◽  
Serena Tomassetti ◽  
Daniela Arzeni ◽  
Daniele Giannini ◽  
...  
Keyword(s):  
Body Weight ◽  
Mouse Model ◽  
Amphotericin B ◽  
Fungal Pathogen ◽  
Candida Glabrata ◽  
Fungicidal Activity ◽  
Disseminated Infection ◽  
Fungicidal Effect ◽  
Time Kill

ABSTRACT We investigated the fungicidal activity of caspofungin (CAS) and amphotericin B (AMB) against 16 clinical isolates of Candida glabrata. The minimum fungicidal concentrations (MFCs) of CAS were similar to those of AMB, ranging from 2.0 to >8.0 μg/ml. Time-kill assays performed on selected isolates showed that AMB was fungicidal at concentrations four times the MIC while CAS was not. A neutropenic-mouse model of disseminated infection was utilized to determine the residual fungal kidney burden. While doses as low as 0.3 and 1 mg/kg of body weight/day of CAS and AMB, respectively, were effective at reducing the counts with respect to controls, organ sterilization was reached when both drugs were administered at 5 mg/kg/day. Our study reveals that, similar to AMB, CAS has the potential for a fungicidal effect in vivo against this difficult-to-treat fungal pathogen.

Sign in / Sign up

Export Citation Format

Share Document