Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Language
Publication year range
1.
Braz J Microbiol ; 55(1): 133-142, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37995041

ABSTRACT

Infections of fungal origin are mainly caused by Candida spp. Some species, such as C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis, stand out as promoters of diseases in humans. This study evaluated the synthesis and antifungal effects of (E)-3-(furan-2-yl)acrylic acid. The synthesis of the compound showed a yield of 88%, considered high. The minimum inhibitory concentration of the synthetic compound, amphotericin B, and fluconazole isolated against four Candida species ranged from 64 to 512 µg/mL, 1 to 2 µg/mL, and 32 to 256 µg/mL, respectively. The synergistic effect of the test compound was observed when associated with amphotericin B against C. albicans and C. tropicalis, with no antagonism between the substances against any of the strains tested. The potential drug promoted morphological changes in C. albicans, decreasing the amount of resistance and virulence, and reproduction structures, such as the formation of pseudohyphae, blastoconidia, and chlamydospores. Furthermore, it was also possible to identify the fungistatic profile of the test substance by studying the growth kinetics of C. albicans. Finally, it was observed that the test compound stimulated ergosterol biosynthesis by the yeast, probably by activating microbial resistance responses.


Subject(s)
Antifungal Agents , Candida , Humans , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Amphotericin B/pharmacology , Acrylates/pharmacology , Fluconazole/pharmacology , Candida albicans , Candida parapsilosis , Microbial Sensitivity Tests , Candida glabrata , Drug Resistance, Fungal
2.
Appl Microbiol Biotechnol ; 105(18): 6559-6578, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34453564

ABSTRACT

The Caatinga is an exclusively Brazilian biome where semiarid climatic conditions promote singularities in adaptive biodiversity. Many aromatic species are found in this region possessing antifungal properties, which are attributed to their essential oils. Thus, we questioned whether essential plant oils found in the Caatinga present anti-dermatophytic potential. Dermatophytes are keratinophilic fungi that cause one of the most prevalent mycoses globally, skin infections known as dermatophytoses (tineas). Here, we provide a comprehensive report of the available published information, analyzing the methods used to evaluate the antifungal activity, verifying the quality of the evidence and possible clinical applications, and discussing research trends in this area. The plants studied concentrated in the genera Croton (Euphorbiaceae), Lippia (Verbenaceae), Piper (Piperaceae), and Mentha (Lamiaceae). All of the studies used in vitro tests to analyze antifungal potential, and little evidence was ascertained concerning the mechanism of antifungal action. In addition, the essential oils also evidenced drug modifying activity of conventional antifungal drugs (Ketoconazole and Terbinafine). We believe that the anti-dermatophyte potential of plant essential oils occurring within the Caatinga is underestimated and that this review will encourage future chemical-pharmacological investigations into the plants within this biome.Key points• The essential oils from plants occurring in the Caatinga Biome present unknown anti-dermatophyte potential.• The studies against dermatophyte fungi concentrate on the families Lamiaceae and Verbenaceae.• In vitro assays were used to assess the anti-dermatophyte potential of the essential oils.


Subject(s)
Oils, Volatile , Tinea , Antifungal Agents/pharmacology , Ecosystem , Humans , Microbial Sensitivity Tests , Oils, Volatile/pharmacology , Plant Oils
3.
AAPS PharmSciTech ; 21(7): 246, 2020 Aug 27.
Article in English | MEDLINE | ID: mdl-32856115

ABSTRACT

Enterococcus faecalis infections represent a health concern, mainly in oral diseases, in which treatments with chlorhexidine solution (0.2%) are often used; however, it presents high toxicity degree and several side effects. Based on this, the use of natural products as an alternative to treatment has been explored. Nonetheless, plant extracts have poor organoleptic characteristics that impair theirs in natura use. Therefore, this work aimed to evaluate the analytical profile, biological activity, and cytotoxicity in vitro of S. brasiliensis-loaded chitosan microparticles (CMSb) produced using different aspersion flow rates. The analytical fingerprint was obtained by FTIR and NIR spectra. Principal components analysis (PCA) was used to verify the similarity between the samples. The crystallinity degree was evaluated by X-ray diffraction (XRD). Phytochemical screening (PS) was performed to quantify phytocompounds. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC). Antibiofilm activity and bactericidal kinetics against E. faecalis (ATCC 29212 and MB 146-clinical isolated) were also assessed. The hemolytic potential was performed to evaluate the cytotoxicity. Data provided by FTIR, NIR, and PCA analyses revealed chemical similarity between all CMSb. Furthermore, the results from XRD analysis showed that the obtained CMSb present amorphous characteristic. Tannins and polyphenols were accurately quantified by the PS, but methodology limitations did not allow the flavonoid quantification. The low hemolytic potential assay indicates that all samples are safe. Antimicrobial assays revealed that CMSb were able to inhibit not only the E. faecalis ATCC growth but also the biofilm formation. Only one CMSb sample was able to inhibit the clinical strain. These results highlighted the CMSb antimicrobial potential and revealed this system as a promising product to treat infections caused by E. faecalis.


Subject(s)
Anacardiaceae , Anti-Infective Agents/administration & dosage , Chitosan/administration & dosage , Enterococcus faecalis/drug effects , Microspheres , Plant Extracts/administration & dosage , Administration, Oral , Anti-Infective Agents/isolation & purification , Biofilms/drug effects , Biofilms/growth & development , Enterococcus faecalis/physiology , Gram-Positive Bacterial Infections/drug therapy , Humans , Microbial Sensitivity Tests/methods , Particle Size , Plant Bark , Plant Extracts/isolation & purification
4.
J Chromatogr Sci ; 47(9): 749-55, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19835682

ABSTRACT

We describe the validation data of a simple but selective chromatographic method for determination of ampicillin in human plasma using liquid chromatography-diode array detector. Blank plasma free of drugs was transferred to eppendorf's tubes and spiked with ampicillin stock solution to obtain quality control samples at 1.00, 2.50, 5.00, and 10.00 microg/mL. Extraction of ampicillin and cephalexin (internal standard) from plasma samples (250 microL) was investigated using three different methods: precipitation with perchloric acid, ultra-filtration and solid-phase extraction. Chromatographic separation was achieved using a Shimpak C(18) column (300 mm x 4.6 mm i.d.; 5 microm), and detection was done at 215 nm with a diode array UV-Vis detector. The mobile phase consisted of dihydrogen phosphate (pH 3.5)-acetonitrile (87.5:12.5, v/v) delivered at a flow rate of 1.00 mL/min. Selectivity was evaluated with different pools of human plasma. Perchloric acid precipitation showed an excellent selectivity for normal plasma. The precipitation method presented recoveries above 84.0 +/- 3.3% and 82.0 +/- 1.6%, (n = 3) for ampicillin and cephalexin, respectively. The method has a limit of detection of 0.15 microg/mL and is linear in the range of 0.30 to 100.00 microg/mL. Standardized residue analysis demonstrated normality and homocedasticity. Inter-day precision was 4.5%, and accuracy was 11.1% (n = 9). Stability studies demonstrated instability of b-lactamics in human plasma at 20 and 2 degrees C after 6 and 360 h of storage, respectively.


Subject(s)
Ampicillin/blood , Chromatography, Liquid/methods , Chromatography, Liquid/instrumentation , Humans , Sensitivity and Specificity , Spectrophotometry, Ultraviolet
5.
Phytochem Anal ; 16(4): 267-71, 2005.
Article in English | MEDLINE | ID: mdl-16042153

ABSTRACT

A method for the quantification of aflatoxins B1, G1, B2 and G2 in the medicinal herb Maytenus ilicifolia was developed and validated. The method used immunoaffinity columns for sample clean-up and HPLC with fluorescence detection without any derivatisation step. The method showed good inter-day accuracy (bias values in the range 4.5-10.7%) and precision (5-16% RSD) when applied to the determination of levels of aflatoxins ranging from 7 to 20 ppb in the plant material. The detection limits for samples of the plant material spiked with aflatoxins were 3.5 ng/g for B1 and G1 and 0.1 ng/g for B2 and G2. The method was successfully applied to commercial samples of Maytenus ilicifolia for the screening of aflatoxin contaminants.


Subject(s)
Aflatoxins/analysis , Chromatography, High Pressure Liquid/methods , Maytenus/chemistry , Brazil , Chromatography, Affinity , Plant Extracts/chemistry , Reproducibility of Results , Spectrometry, Fluorescence
SELECTION OF CITATIONS
SEARCH DETAIL
...