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F D D'Auria

Publications and source records attributed to F D D'Auria.

At least 19 recordsLinked to original sources
PubMed2006

Multifactorial aspects of antimicrobial activity of propolis.

We investigated the antibacterial activity of sub-inhibitory concentrations of ethanolic extract of propolis (EEP), and its effect on the antibacterial activity of some antibiotics. Some clinically isolated Gram-positive strains were used. Moreover, sub-inhibitory concentrations of EEP were used to value its action on some important virulence factors like lipase and coagulase enzymes, and on biofilm formation in Staphylococcus aureus. Our results indicated that EEP had a significant antimicrobial activity towards all tested clinical strains. Adding EEP to antibacterial tested drugs, it drastically increased the antimicrobial effect of ampicillin, gentamycin and streptomycin, moderately the one of chloramphenicol, ceftriaxon and vancomycin, while there was no effect with erithromycin. Moreover, our results pointed out an inhibitory action of EEP on lipase activity of 18 Staphylococcus spp. strains and an inhibitory effect on coagulase of 11 S. aureus tested strains. The same EEP concentrations showed a negative interaction with adhesion and consequent biofilm formation in S. aureus ATCC 6538P.

Anti-Bacterial Agents↗
PubMed2005

Antifungal activity of Lavandula angustifolia essential oil against Candida albicans yeast and mycelial form.

The antifungal activity of the essential oil of Lavandula angustifolia Mill. (lavender oil) and its main components, linalool and linalyl acetate, was investigated against 50 clinical isolates of Candida albicans (28 oropharyngeal strains, 22 vaginal strains) and C. albicans ATCC 3153. Growth inhibition, killing time and inhibition of germ tube formation were evaluated. The chemical composition of the essential oil was determined by gas chromatography and mass spectrometry. Lavender oil inhibited C. albicans growth: mean minimum inhibitory concentration (MIC) of 0.69% (vol./vol.) (vaginal strains) and 1.04% (oropharyngeal strains); mean MFC of 1.1% (vaginal strains) and 1.8% (oropharyngeal strains). Linalool was more effective than essential oil: mean MIC of 0.09% (vaginal strains) and 0.29% (oropharyngeal strains); mean MFC of 0.1% (vaginal strains) and 0.3% (oropharyngeal strains). Linalyl acetate was almost ineffective. Lavender oil (2%) killed 100% of the C. albicans ATCC 3153 cells within 15 min; linalool (0.5%) killed 100% of the cells within 30 s. The essential oil inhibited germ tube formation (mean MIC of 0.09%), as did the main components (MIC of 0.11% for linalool and 0.08% for linalyl acetate). Both the essential oil and its main components inhibited hyphal elongation of C. albicans ATCC 3153 (about 50% inhibition at 0.016% with each substance). Lavender oil shows both fungistatic and fungicidal activity against C. albicans strains. At lower concentrations, it inhibits germ tube formation and hyphal elongation, indicating that it is effective against C. albicans dimorphism and may thus reduce fungal progression and the spread of infection in host tissues.

Antifungal Agents↗
PubMed2003

Effect of propolis on virulence factors of Candida albicans.

Propolis is a resinous substance collected by honeybees from plant sources. Its antimicrobial activity has been well documented but little is specifically known about its activity on virulence factors of Candida albicans. The aim of this work was therefore to evaluate in vitro the propolis effect on yeast-mycelial conversion (Y-M), extracellular phospholipase activity and fungal adhesion to epithelial cells. The two propolis samples used significantly inhibited the C. albicans strains tested, showing a rapid (between 30 seconds and 15 minutes), dose-dependent cytocidal activity and an inhibitory effect on Y-M conversion at a concentration of 0.22 mg/ml. Moreover, the hyphal length was reduced even at lower propolis concentration. Propolis also caused a dose- and time-dependent inhibition of phospholipase activity. No clear effect was shown on adherence to buccal epithelial cells and surface structure hydrophobicity, but damage to the plasma membrane structure was demonstrated with the Propidium Iodide test.

Anti-Infective Agents↗
PubMed2001

In vitro activity of propyl gallate-azole drug combination against fluconazole- and itraconazole-resistant Candida albicans strains.

AIMS: The influence of an antioxidant, propyl gallate (PG), on the in vitro antifungal activity of itraconazole and fluconazole, was investigated to determine whether PG could increase the antifungal activity and reduce strain resistance. METHODS AND RESULTS: Susceptibility tests were performed against azole-resistant isolates of Candida albicans by the microbroth dilution method in the presence of PG at 400 microg ml-1. PG-triazole combination brought about a marked reduction of inhibitory azole concentration. In particular, the MIC90 for itraconazole and fluconazole dropped from 1 microg ml-1 to 0.125 microg ml-1 and from > 64 microg ml-1-8 microg ml-1, respectively. CONCLUSION: It is likely that more than one mechanism is involved in the above synergistic interaction, including effects of PG on ATP synthesis, thus reducing the ABC transporters activity, or an effect on the target of azole, i.e. the P-450 cytochrome. SIGNIFICANCE AND IMPACT OF THE STUDY: The PG-triazole combination may have a role in future topical antifungal strategies but other studies are warranted.

Antifungal Agents↗
PubMed2001

In vitro activity of tea tree oil against Candida albicans mycelial conversion and other pathogenic fungi.

The antifungal activity of Melaleuca alternifolia Maiden (Myrtaceae) essential oil against yeasts (Candida spp., Schizosaccharomyces pombe, Debaryomyces hansenii) and dermatophytes (Microsporum spp. and Tricophyton spp.) is reported. We focused on the ability of tea tree oil to inhibit Candida albicans conversion from the yeast to the pathogenic mycelial form. Moreover we carried out broth microdilution test and contact tests to evaluate the killing time. M. alternifolia essential oil inhibited the conversion of C. albicans from yeast to the mycelial form at a concentration of 0.16% (v/v). The minimum inhibitory concentrations (MICs) ranged from 0.12% to 0.50% (v/v) for yeasts and 0.12% to 1% (v/v) for dermatophytes; the cytocidal activity was generally expressed at the same concentration. These results, if considered along with the lipophilic nature of the oil which enables it to penetrate the skin, suggest it may be suitable for topical therapeutic use in the treatment of fungal mucosal and cutaneous infections.

Anti-Infective Agents, Local↗
PubMed2000

Anticandidal activity of SPA-S-843, a new polyenic drug.

The activity of a new, soluble and stable polyene (SPA-S-843) against Candida albicans was assessed by contact and culture tests and by inhibition of germ-tube formation. The drug demonstrated a higher contact activity and lower MICs than amphotericin B. This antimicrobial activity was more evident under acid pH and low ionic strength. In addition, the ability of SPA-S-843 to inhibit Candida sp. conversion from yeast to mycelial form was evident at low drug concentrations (0.25-0.62 mg/L).

Amphotericin B↗
PubMed1991

Antimicrobial contact activity of econazole sulfosalicylate.

The aim of this investigation was to compare the contact action of econazole sulfosalicylate (E-SSA) on mycetes (Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, Trichophyton rubrum, T. cutaneum, Pityrosporum sp.), Gram-positive bacteria (Staphylococcus aureus, Streptococcus faecalis) and Gram-negative bacteria (Escherichia coli, Citrobacter freundii) with that exerted by econazole nitrate (E-NIT). The results show E-SSA activity greater than E-NIT (in particular against mycetes and Gram-negative bacteria). The E-SSA contact activity trials illustrated certain properties of this imidazole sulfosolicylate such as: absence of latency time, antimicrobial activity proportional to its concentration, when a high concentration is used, given the limiting influence of pH and ionic strength of the medium. The higher E-SSA contact activity, in relation to E-NIT, can be correlated to its greater lipophylia considering also the lipophylic properties of SSA and the scarce dissociation of E-SSA.

Aspergillus fumigatus↗
PubMed1991

Increased in vitro sensitivity of Candida albicans to fluconazole.

Sodium dioctyl sulfosuccinate (SDSS), an anionic surfactant used at a non-antimicrobial concentration, increased the sensitivity of Candida albicans to fluconazole in complex media (such as Sabouraud). The conditions were assessed to determine the in vitro sensitivity to fluconazole. In this connection, the use of a liquid medium at a non-alkaline pH is important. The presence of SDSS in complex media does not seem to affect the neutralization of a particular substances but favours the activity of fluconazole.

Candida albicans↗
PubMed1990

Investigations of the activity by contact of miconazole sulfosalicylate.

The in-vitro antimicrobial activity of miconazole sulfosalicylate (M.SSA) has been investigated on mycetes (Candida albicans, Cryptococcus neoformans, Aspergillus niger, Trichophyton mentagrophytes), Gram-positive bacteria (Staphylococcus aureus, Streptococcus faecalis) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens and Proteus vulgaris) in comparison with miconazole nitrate (M.NIT). The results showed M.SSA has a greater activity than M.NIT, particularly on mycetes and Gram-negative bacteria. The study of activity by contact with M.SSA showed some characteristics of this sulfosalicylate imidazole, such as the lack of a latency time, an antimicrobic action related directly to the concentration, the limited influence of pH and ionic strength of medium used. The greater activity by contact of M.SSA than M.NIT could be related to its higher lipophilia (due also to the lipophilic characteristics of SSA) and, therefore, to increased interaction with the cell membrane.

Candida albicans↗
PubMed1990

In vitro antimicrobial activity of econazole and miconazole sulfosalicylate.

The in vitro activities of new sulfosalicylic salts of econazole (E.SSA) and miconazole (M.SSA) have been investigated in comparison with the respective nitrate (NIT) salts and sulfosalicylic acid (SSA) alone. The results reveal good antimicrobial activity of M.SSA and E.SSA against different strains of Candida, dermatophytes, moulds, Gram-positive bacteria and Trichomonas vaginalis. The MIC values demonstrate that M.SSA is more active than M.NIT on Candida and T. vaginalis. E.SSA was also more active than E.NIT on T.vaginalis. Both SSA and sodium sulfosalicylate (NaSSA) were practically without activity by themselves. Finally, the pH variations did not significantly modify the activity of the SSA salts, suggesting that their greater activity could be due to better lipophilic activity of these compounds with respect to the nitrate salts.

Animals↗
PubMed1989

Glycogen medium, antitrichomonal drug activity in vaginal liquids.

The amount of glycogen in vaginal liquids decreases with Trichomonas vaginalis and this is connected with T. vaginalis activity in specimens. A glycogen-hydrolysed casein medium ("glycogen medium") added to vaginal liquid is a valid maintenance medium for T. vaginalis and therefore enables a direct test for antitrichomonas drugs to be performed.

Animals↗
PubMed1989

[Substances with antibacterial and antifungal activity. VII. Synthesis and microbiologic activity of new derivatives of 1,5-diarylpyrrole].

The synthesis and antifungal activities of new 1,5-diarylpyrrole derivatives are reported. Antimicrobial data in comparison with pyrrolnitrin show that N-methylpiperazinylamides exhibit very poor activity against Candida albicans and Candida sp. while acid and ester derivatives are inactive. Vice-versa many acid or amide derivatives show interesting antibacterial activity. The results obtained are discussed on the basis of structure-activity relationships.

Anti-Bacterial Agents↗
PubMed1988

Itraconazole: increased activity by chlorhexidine.

Chlorhexidine increases the activity of itraconazole against Candida isolates; itraconazole-chlorhexidine combinations show synergistic activity in culture media. The activity of itraconazole is discussed.

Animals↗
PubMed1988

A study of the antifungal activity of LY121019, a new echinocandin derivative.

LY121019 is a cyclic peptide antibiotic of the echinocandin group, which is characterized by strong anti-Candida activity (in particular against Candida albicans) as well as by low experimental toxicity. Its anti-Candida activity is thought to be due to an inhibition of the synthesis of beta-glucan, an essential cell wall polysaccharide. The different composition of culture media or the presence of animal serum did not show adverse effects on LY121019's anti-Candida activity and the addition of reducing compounds such as cysteine and hydroquinone did not manifest a negative influence. Analogously the anti-Candida activity was not influenced when C. albicans was grown under aeration. The activity of LY121019 was very high against the mycelial form of C. albicans even when this form was developed in the presence of animal serum.

Antifungal Agents↗
PubMedDate not supplied

Antifungal activity of ketoconazole and other azoles against Malassezia furfur in vitro and in vivo.

The in vitro activity of several antifungal agents (ketoconazole, miconazole, econazole, fenticonazole, itraconazole, fluconazole) in routine clinical use against Malassezia furfur infections has been studied with freshly isolated strains of M. furfur from pityriasis versicolor lesions. The results indicate that the drugs tested exert a good activity, and both ketoconazole and itraconazole appear very active (0.8 mg/l respectively). Hair samples from the beards of volunteer patients affected by pityriasis versicolor but otherwise healthy were examined to determine ketoconazole levels during oral therapy (one or two 200 mg tablets daily). It was shown that the drug progressively accumulates in the beard, reaching levels proportional to the dose administered, although blood levels did not increase in parallel. The study of drug concentration profile has evidenced a long ketoconazole persistence in the beard at therapeutic levels. In conclusion, the possibility of reaching high and lasting ketoconazole levels in the keratin layer of the epidermis indicates that systemic ketoconazole therapy could be useful for eradication of M. furfur in patients affected by pityriasis versicolor.

Adult↗
PubMedDate not supplied

In vivo and in vitro antifungal activity of the polyene derivative SPA-S-753 against encapsulated form of Cryptococcus neoformans.

The in vitro and in vivo activity of SPA-S-753 (N-dimethylaminoacetyl-partricin A 2-dimethylaminoethylamide diaspartate), a new water soluble polyene, was compared with amphotericin B against Cryptococcus neoformans in encapsulated (K) and nonencapsulated (N) morphological forms. In vitro tests against 17 isolates of C. neoformans (in K or N form) showed that SPA-S-753 activity is about ten times higher than that of amphotericin B. In direct contact tests the SPA-S-753 cytocidal action was significantly higher than that of amphotericin B; the K cells are, however, less sensitive to the cytocidal action exerted by the two polyenes even when using concentrations 4-fold higher than those used against the N cells and they present a smaller potassium ion release. The cytocidal activity of the two polyenes is favoured by a low electrolyte concentration and an acid pH. SPA-S-753 microbicidal activity by contact in vivo, in mice infected with C. neoformans N cells by i.p. route, is more powerful than that of amphotericin B. In protection tests in mice infected with 10 LD50 of C. neoformans K cells, SPA-S-753 action is again more powerful, but not to a significant degree, than that of amphotericin B. In conclusion, both substances showed a reduced in vitro and in vivo activity against C. neoformans in the K morphological form. Nevertheless our results demonstrate that SPA-S-753 exerts an antifungal overall activity that is more effective than that of amphotericin B under similar experimental conditions.

Amphotericin B↗