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"von Zeska Kress, Marcia Regina"
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Essential Oil-Based Soap with Clove and Oregano: A Promising Antifungal and Antibacterial Alternative against Multidrug-Resistant Microorganisms
by
Santos, Vinícius Cristian Oti dos
,
Von Zeska Kress, Marcia Regina
,
Cruz, Ana Paula Merino
in
Anti-Bacterial Agents - chemistry
,
Anti-Bacterial Agents - pharmacology
,
antibacterial activity
2024
The transmission of microorganisms via hands is a critical factor in healthcare-associated infections (HAIs), underscoring the importance of rigorous hand hygiene. The rise of antimicrobial-resistant microorganisms, driven in part by the overuse of antibiotics in clinical medicine, presents a significant global health challenge. Antimicrobial soaps, although commonly used, may exacerbate bacterial resistance and disrupt skin microbiota, posing additional health risks and environmental hazards. Essential oils, with their broad-spectrum antimicrobial properties, offer a promising alternative. This study evaluates the antimicrobial activity of essential oils against various bacterial and fungal strains, including multidrug-resistant isolates. Using a range of in vitro and in vivo antimicrobial assays, including minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), and minimal fungicidal concentration (MFC), the essential oils were tested against a broad spectrum of pathogens. Additionally, the chemical composition of the oils was analyzed in detail using gas chromatography–mass spectrometry (CG–MS). Clove, oregano, and thyme oils demonstrated potent inhibition of all tested ATCC bacterial strains, with MIC values ranging from 3.125 to 50 μL/mL. These oils also showed significant activity against multidrug-resistant Escherichia coli and Pseudomonas aeruginosa strains. Notably, clove oil exhibited remarkable efficacy against fungal strains such as Aspergillus fumigatus and Trichophyton rubrum, with MIC values as low as 1.56 μL/mL. Synergy tests revealed that combinations of clove, oregano, and thyme oils yielded significantly lower MIC values than individual oils, indicating additive or synergistic effects. The formulation of a soap incorporating clove and oregano oils demonstrated efficacy comparable to synthetic antiseptics in vivo. These findings highlight the exceptional antimicrobial potential of essential oils, mainly clove and oregano, against resistant microorganisms, offering a viable alternative to conventional antimicrobial agents.
Journal Article
Chemical composition and antifungal activity of Capsicum pepper aqueous extracts against plant pathogens and food spoilage fungi
by
Barría, Elsa
,
Sepúlveda, Marcela
,
Rigotto Caruso, Glaucia
in
Animals
,
Antifungal activity
,
Antifungal Agents - chemistry
2024
Capsicum pepper is a rich source of phytochemical compounds such as capsaicinoids, phenols, flavonoids, and so forth. Due to their antimicrobial and antioxidant potential all of these compounds have been assessed and used for both human and plant health benefits. Herein, three fresh varieties of Capsicum annuum (Cacho de Cabra, Bell pepper, and Hungarian Wax varieties) and one fresh and ripe variety of C. baccatum (Cristal) were evaluated. Capsaicin, dihydrocapsaicin, nordihydrocapsaicin and the phenolic content of Capsicum spp. extracts were characterised. The antifungal potential of capsaicinoids and antioxidant activities, and the ecotoxicity of each Capsicum spp. extract, using the model Galleria mellonella , were also evaluated. Phytochemical analyses showed that the Cristal and Hungarian Wax varieties presented the highest amount of capsaicin, dihydrocapsaicin, and nordihydrocapsaicin; while Bell Pepper had the highest phenol content and antioxidant activity. Capsaicinoids’ standards and Capsicum spp. extracts showed fungistatic activity against the fungal strains assessed. For the fungal strains assessed, the fungistatic activities of capsaicinoids’ standards were higher than those observed in Capsicum spp. extracts. The Hungarian Wax extracts inhibited slightly the growth of Aspergillus niger MUM05.11 and Fusarium oxysporum MUM16.143. Similarly, A. niger , F. oxysporum , Rhizopus arrhizus MUM16.05 and Alternaria sp. UFRO17.178 had their growth retarded by the use of Cacho de Cabra and Cristal extracts. Noticeable changes were observed in the fungal strains’ morphologies, such as the presence of fragile fungal structures, pigmentation loss, variation in the reproductive structures size and the conidia number. Capsicum extracts weaken the growth of fungi, indicating their fungistatic potential. Considering the fungistatic potential and non-ecotoxicity of these extracts, it is possible to suggest their use as a tool for pest management in the agri-food sector, controlling the growth and reproduction of fungi without posing a risk to non-target biodiversity.
Journal Article
Characterization of the lipid profile of Antarctic brown seaweeds and their endophytic fungi by gas chromatography–mass spectrometry (GC–MS)
by
Márcia Regina von Zeska Kress
,
Izabel Cristina Casanova Turatti
,
Colepicolo, Pio
in
Algae
,
Aquatic habitats
,
Bioactive compounds
2019
The marine environment supports vast habitats with prodigious biodiversity comprising the largest source of unique bioactive compounds biosynthesized by macro and microorganisms, including seaweeds and their associated fungi. In this context, the interest in studying and characterizing marine natural products has increased in the last years. Among these metabolites, lipids and their derivatives play an important role in the metabolism of marine organisms and are sources of substances with therapeutic properties and biotechnological purposes. In this research, it was investigated the lipid amount present in the algae species Ascoseira mirabilis, Adenocystis utricularis, Desmarestia anceps, Phaeurus antarcticus and in their associated endophytic fungi Aspergillus flavus, Penicillium echinulatum, Microascus croci and Penicillium purpurogenum, respectively. This study was achieved by gas chromatography–mass spectrometry, using a standard methodology to analyze all of the components present in the eight organisms. Fatty acids (FAs) and sterols are among the lipids of the highest concentration in the studied algae and fungi. In general, phytol and fucosterol were the most abundant metabolites in all seaweed, while in endophytic fungi, the FAs (palmitic, linoleic, oleic and stearic acid) and ergosterol appeared in major concentrations. This work contributes to new chemical information on the underexploited biodiversity of macroalgae and endophytic fungi belonging to the Antarctic Peninsula and, furthermore, to increase the possibilities for the discovery of bioactive substances and apply it on biotechnological approaches.
Journal Article
The Immune Interplay between the Host and the Pathogen in Aspergillus fumigatus Lung Infection
by
Sales-Campos, Helioswilton
,
Cardoso, Cristina Ribeiro Barros
,
Tonani, Ludmilla
in
Animals
,
Aspergillosis
,
Aspergillosis - immunology
2013
The interplay between Aspergillus fumigatus and the host immune response in lung infection has been subject of studies over the last years due to its importance in immunocompromised patients. The multifactorial virulence factors of A. fumigatus are related to the fungus biological characteristics, for example, structure, ability to grow and adapt to high temperatures and stress conditions, besides capability of evading the immune system and causing damage to the host. In this context, the fungus recognition by the host innate immunity occurs when the pathogen disrupts the natural and chemical barriers followed by the activation of acquired immunity. It seems clear that a Th1 response has a protective role, whereas Th2 reactions are often associated with higher fungal burden, and Th17 response is still controversial. Furthermore, a fine regulation of the effector immunity is required to avoid excessive tissue damage associated with fungal clearance, and this role could be attributed to regulatory T cells. Finally, in this work we reviewed the aspects involved in the complex interplay between the host immune response and the pathogen virulence factors, highlighting the immunological issues and the importance of its better understanding to the development of novel therapeutic approaches for invasive lung aspergillosis.
Journal Article
Harnessing Machine Learning to Uncover Hidden Patterns in Azole-Resistant CYP51/ERG11 Proteins
by
von Zeska Kress, Marcia Regina
,
Almeida, Otávio Guilherme Gonçalves de
in
Acid resistance
,
Algorithms
,
Amino acid composition
2024
Fungal resistance is a public health concern due to the limited availability of antifungal resources and the complexities associated with treating persistent fungal infections. Azoles are thus far the primary line of defense against fungi. Specifically, azoles inhibit the conversion of lanosterol to ergosterol, producing defective sterols and impairing fluidity in fungal plasmatic membranes. Studies on azole resistance have emphasized specific point mutations in CYP51/ERG11 proteins linked to resistance. Although very insightful, the traditional approach to studying azole resistance is time-consuming and prone to errors during meticulous alignment evaluation. It relies on a reference-based method using a specific protein sequence obtained from a wild-type (WT) phenotype. Therefore, this study introduces a machine learning (ML)-based approach utilizing molecular descriptors representing the physiochemical attributes of CYP51/ERG11 protein isoforms. This approach aims to unravel hidden patterns associated with azole resistance. The results highlight that descriptors related to amino acid composition and their combination of hydrophobicity and hydrophilicity effectively explain the slight differences between the resistant non-wild-type (NWT) and WT (nonresistant) protein sequences. This study underscores the potential of ML to unravel nuanced patterns in CYP51/ERG11 sequences, providing valuable molecular signatures that could inform future endeavors in drug development and computational screening of resistant and nonresistant fungal lineages.
Journal Article
Surveillance of Amphotericin B and Azole Resistance in Aspergillus Isolated from Patients in a Tertiary Teaching Hospital
by
da Fonseca, Lívia Maria Maciel
,
Braga, Vanessa Fávaro
,
Grizante Barião, Patrícia Helena
in
Amino acids
,
Amphotericin B
,
antifungal resistance
2023
The genus Aspergillus harbors human infection-causing pathogens and is involved in the complex one-health challenge of antifungal resistance. Here, a 6-year retrospective study was conducted with Aspergillus spp. isolated from patients with invasive, chronic, and clinically suspected aspergillosis in a tertiary teaching hospital. A total of 64 Aspergillus spp. clinical isolates were investigated regarding molecular identification, biofilm, virulence in Galleria mellonella, antifungal susceptibility, and resistance to amphotericin B and azoles. Aspergillus section Fumigati (A. fumigatus sensu stricto, 62.5%) and section Flavi (A. flavus, 20.3%; A. parasiticus, 14%; and A. tamarii, 3.1%) have been identified. Aspergillus section Flavi clinical isolates were more virulent than section Fumigati clinical isolates. Furthermore, scant evidence supports a link between biofilm formation and virulence. The susceptibility of the Aspergillus spp. clinical isolates to itraconazole, posaconazole, voriconazole, and amphotericin B was evaluated. Most Aspergillus spp. clinical isolates (67.2%) had an AMB MIC value equal to or above 2 µg/mL, warning of a higher probability of therapeutic failure in the region under study. In general, the triazoles presented MIC values above the epidemiological cutoff value. The high triazole MIC values of A. fumigatus s.s. clinical isolates were investigated by sequencing the promoter region and cyp51A locus. The Cyp51A amino acid substitutions F46Y, M172V, N248T, N248K, D255E, and E427K were globally detected in 47.5% of A. fumigatus s.s. clinical isolates, and most of them are associated with high triazole MICs. Even so, the findings support voriconazole or itraconazole as the first therapeutic choice for treating Aspergillus infections. This study emphasizes the significance of continued surveillance of Aspergillus spp. infections to help overcome the gap in knowledge of the global fungal burden of infections and antifungal resistance, supporting public health initiatives.
Journal Article
Cryptococcus neoformans and C. gattii isolates from both HIV-infected and uninfected patients: antifungal susceptibility and outcome of cryptococcal disease
by
Nascimento, Erika
,
Vitali, Lucia Helena
,
Martinez, Roberto
in
AIDS-Related Opportunistic Infections - microbiology
,
Antifungal agents
,
Antifungal Agents - pharmacology
2017
One of the factors causing treatment failure in cryptococcosis is the resistance of Cryptococcus spp. to antifungal drugs, which has motivated the susceptibility assessment of isolates from patients with cryptococcosis, different clinical conditions and infections outcomes. Clinical isolates of Cryptococcus spp. from three different groups of patients were studied in the present investigation: 19 HIV-positive patients with relapsing and/or refractory meningitis (Group 1), 30 HIV-positive patients who experienced a single and limited episode of cryptococcosis (Group 2), and 19 HIV-negative patients with cryptococcosis (Group 3). Eighty C. neoformans var. grubii isolates and 7 C. gattii isolates were studied. The minimum inhibitory concentration (MIC) of amphotericin B, azole drugs and flucytosine was determined for Cryptococcus spp. by broth microdilution test and E-test. The MIC50 and MIC90 were 0.25 and 0.50 µg/mL for amphotericin B, 4.0 and 8.0 µg /mL for fluconazole, 0.06 and 0.25 µg/mL for itraconazole, 0.25 and 0.50 µg/mL for voriconazole, and 8.0 and 16.0 µg/mL for flucytosine, respectively. Amphotericin B and itraconazole showed higher MICs for C. neoformans var. grubii and C. gattii, respectively. The MICs of fluconazole and itraconazole obtained with the E-test were higher than those obtained with broth microdilution. Isolates from non-HIV coinfected were less sensitive to the azoles. There was no difference in the susceptibility of C. neoformans var. grubii isolates from patients with a favorable or unfavorable outcome or along the episodes of relapsing and/or refractory meningitis.
Journal Article
Antagonistic Interactions in Onychomycosis: Antifungal Activity of Extracts from Pure and Mixed Cultures of Candida parapsilosis and Trichophyton spp
by
de Almeida, Margarete Teresa Gottardo
,
Lemes, Thiago Henrique
,
Nascentes, Julyanna Andrade Silva
in
antagonism
,
Antifungal activity
,
Antifungal agents
2024
Onychomycoses are nail infections that require prolonged therapy and have high recurrence rates. Dermatophytes are the main etiological agents of these infections, followed by yeasts and non-dermatophyte filamentous fungi. The limited antifungal arsenal used to treat onychomycosis and the change in the susceptibility profile of these agents contribute to the chronicity and recalcitrant profile of infections. The present study aimed to determine the antifungal activity of extracts obtained from pure and mixed cultures of Candida parapsilosis, Trichophyton mentagrophytes, and Trichophyton rubrum. Additionally, in vivo toxicity tests with Galleria mellonella and time-kill assays were carried out. The susceptibility profiles of dermatophytes were determined using a microdilution technique with minimum inhibitory concentrations (MICs) between 250 and 8000 µg/mL. The time-kill assay, compared to growth control, resulted in the death of dermatophytes within 48 h. No toxicity of the extracts was detected in experiments with Galleria mellonella larvae under the test conditions. The extracts of pure and mixed cultures of Candida parapsilosis and dermatophytes present antifungal activity against T. mentagrophytes and T. rubrum. Isolating and identifying compounds in the extracts may allow the development of new therapeutic approaches to control fungal infections.
Journal Article
MALDI-TOF MS: A Quick Method to Detect the Susceptibility of Fusarium spp. Clinical Isolates to Amphotericin B
by
Sepúlveda, Marcela
,
Dias, Nathalia
,
Santos, Cledir
in
Amphotericin B
,
antibiotic resistance
,
Antimicrobial resistance
2023
Disseminated fusariosis is treated with amphotericin B and voriconazole. To determine adequate therapy, the minimal inhibitory concentration (MIC) is used. However, MIC analysis is based on visual observation and requires a long period of fungal incubation. The measure of the minimal profile change concentration (MPCC) using MALDI-TOF MS is a quick spectral method that has presented good results in determining the antimicrobial resistance of yeasts. However, there is a lack of information on filamentous fungi. In the present work, 13 Fusarium spp. clinical isolates and two reference strains were used. MIC was obtained according to the M38-A2 protocol of the Clinical Laboratory Standards Institute, while MPPC was obtained following the initial steps of the M38-A2 protocol. Both Biotyper and the Rstudio environment were used to analyze mass spectra. For some fungal strains, the data obtained from the software MALDI Biotyper Compass 4.1 led to fuzzy heatmaps resulting in difficult interpretation, while heatmaps obtained using Rstudio tools generated better MPCC resolutions. Herein, 86.6% of the AMB MPCC values were highly correlated with the gold-standard AMB MIC. MALDI-TOF MS is a prominent tool used to determine MPCCs quicker, cost-effectively, and more accurately for Fusarium spp. strains. However, better statistical analyses could help measure the technique’s limit detection.
Journal Article
Paracoccidioidomycosis due to Paracoccidioides lutzii complicated with adrenal injury and pulmonary arterial hypertension
by
Gaspar, Gilberto Gambero
,
Cocio, Tiago Alexandre
,
Fabro, Alexandre Todorovic
in
Case Report
,
Paracoccidioides lutzii
,
Paracoccidioidomycosis
2020
Paracoccidioidomycosis caused by Paracoccidioides lutzii is endemic in the Midwest of Brazil and its clinical spectrum is still little known due to the recent identification of this fungal species. A patient resident in Southeast Brazil, but who had lived for many years in the Midwest region, presented with skin injuries, chronic cough and bilateral adrenal involvement. Paracoccidioides spp. was isolated in culture from a skin lesion biopsy. This isolate was later identified as P. lutzii using gene sequencing. A favorable initial response to treatment with itraconazole was observed, but a few weeks later, the patient developed respiratory failure and worsening of lung lesions. Evaluation by computed tomography and echocardiography were suggestive of pulmonary arterial hypertension, and a bronchoscopic biopsy showed peribronchial remodeling. The patient completed the antifungal treatment but maintained the respiratory dysfunction. The reported case shows that P. lutzii can be isolated from patients in a geographic area far from the place of infection acquisition and that, as P. brasiliensis , it can cause adrenal injury and cardio-respiratory complications as a consequence of excessive necrosis and fibrosis.Paracoccidioidomycosis caused by Paracoccidioides lutzii is endemic in the Midwest of Brazil and its clinical spectrum is still little known due to the recent identification of this fungal species. A patient resident in Southeast Brazil, but who had lived for many years in the Midwest region, presented with skin injuries, chronic cough and bilateral adrenal involvement. Paracoccidioides spp. was isolated in culture from a skin lesion biopsy. This isolate was later identified as P. lutzii using gene sequencing. A favorable initial response to treatment with itraconazole was observed, but a few weeks later, the patient developed respiratory failure and worsening of lung lesions. Evaluation by computed tomography and echocardiography were suggestive of pulmonary arterial hypertension, and a bronchoscopic biopsy showed peribronchial remodeling. The patient completed the antifungal treatment but maintained the respiratory dysfunction. The reported case shows that P. lutzii can be isolated from patients in a geographic area far from the place of infection acquisition and that, as P. brasiliensis , it can cause adrenal injury and cardio-respiratory complications as a consequence of excessive necrosis and fibrosis.
Journal Article