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1.
Arch Microbiol ; 205(4): 149, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36995448

RESUMO

Biosurfactants are surface-active molecules that are synthesized by many microorganisms like fungi, bacteria, and yeast. These molecules are amphiphilic in nature, possessing emulsifying ability, detergency, foaming, and surface-activity like characteristics. Yeast species belongs to the genus Candida has gained globally enormous interest because of the diverse properties of biosurfactants produced by theme. In contrast to synthetic surfactants, biosurfactants are claimed to be biodegradable and non-toxic which labels them as a potent industrial compound. Biosurfactants produced by this genus are reported to possess certain biological activities, such as anticancer and antiviral activities. They also have potential industrial applications in bioremediation, oil recovery, agricultural, pharmaceutical, biomedical, food, and cosmetic industries. Various species of Candida have been recognized as biosurfactant producers, including Candida petrophilum, Candida bogoriensis, Candida antarctica, Candida lipolytica, Candida albicans, Candida batistae, Candida albicans, Candida sphaerica, etc. These species produce various forms of biosurfactants, such as glycolipids, lipopeptides, fatty acids, and polymeric biosurfactants, which are distinct according to their molecular weights. Herein, we provide a detailed overview of various types of biosurfactants produced by Candida sp., process optimization for better production, and the latest updates on the applications of these biosurfactants.


Assuntos
Candida , Tensoativos , Tensoativos/farmacologia , Tensoativos/química , Bactérias , Leveduras , Candida albicans
2.
Arch Microbiol ; 204(3): 172, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35165751

RESUMO

In the recent years, yeasts have evolved as potent bioremediative candidates for the detoxification of xenobiotic compounds found in the natural environment. Candida sp. are well-studied apart from Saccharomyces sp. in heavy metal detoxification mechanisms. In the current study, Candida parapsilosis strain ODBG2, Candida sp. strain BANG3, and Candida viswanathii strain ODBG4 were isolated from industrial effluents and contaminated ground water, and were studied for their metal tolerance. Among these three isolates, the metal tolerance was found to be more towards Lead (Pb 2 mM), followed by Cadmium (Cd 1.5 mM) and Chromium [Cr(VI), 1 mM]. On further exploring the involvement of primary defensive enzymes in these isolates towards metal tolerance, the anti-oxidative enzyme superoxide dismutase was found to be prominently high (25% with respect to the control) during first 24 h of metal-isolate interaction. The Catalase enzyme assay was observed to have increased enzyme activity at 48 h. It also triggered the activity of peroxidases, which lead to the increase in reduced glutathione in the organism by 0.87-1.9-fold as a metal chelator and also as a second-line defensive molecule. The exoproteome profile showed the early involvement (exponential growth phase) of secreted proteins (low-molecular-weight) of about ~ 40-45 kDa under Cd and Pb stress (0.5 mM). The exoproteome profiling under heavy metal stress in Candida parapsilosis strain ODBG2 and Candida viswanathii strain ODBG4 is the first report.


Assuntos
Metais Pesados , Saccharomyces cerevisiae , Cádmio/toxicidade , Cromo , Metais Pesados/toxicidade , Estresse Oxidativo
3.
J Sci Food Agric ; 102(15): 7115-7125, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35704042

RESUMO

BACKGROUND: α-Lipoic acid has excellent antioxidant activity, but its poor lipid solubility greatly limits its practical application. This study was undertaken (i) to develop a novel and efficient enzymatic synthesis of lipophilic lipoic acid esters using Candida sp. 99-125 lipase as a catalyst; and (ii) to systematically evaluate their antioxidant potential against bulk oil, oil-in-water emulsion (O/W) and cooked ground meat. RESULTS: Lipophilic lipoic acid esters were successfully and efficiently synthesized using phytosterols as acyl receptor in the presence of Candida sp. 99-125 lipase. The product was identified as phytosterol lipoate by mass spectrometry, Fourier transform infrared spectroscopy and nuclear magnetic resonance. The maximum conversion of phytosterol lipoate surpassed 90% within 12 h and its final yield exceeded 81%. Interestingly, the oil solubility of lipoic acid was increased at least 25-fold and other physicochemical properties were significantly improved. Most importantly, phytosterol lipoate exhibited higher antioxidant activity than lipoic acid in bulk oil, O/W emulsions and cooked ground meat. CONCLUSION: The antioxidant capacity of lipoic acid can be significantly enhanced by esterification with phytosterols. Therefore, phytosterol lipoate could be further developed as a new antioxidant for use in oil- and fat-based foods. © 2022 Society of Chemical Industry.


Assuntos
Fitosteróis , Ácido Tióctico , Esterificação , Lipase/química , Fitosteróis/química , Antioxidantes , Ésteres/química
4.
BMC Oral Health ; 22(1): 455, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36303145

RESUMO

BACKGROUND: This pilot study aimed to investigate how fixed orthodontic appliances simultaneously applied on the upper and lower arches affect the oral environment in the medium term. METHODS: The oral status of 30 orthodontic patients was evaluated using the number of decay-missing-filled teeth (DMFT), plaque (PI), and gingival indices (GI) before bonding of fixed orthodontic appliances (T0) and during the therapy (T1). Besides, the gingival crevicular fluid (GCF) and a dental plaque were collected. Samples were analyzed for selected Candida sp. and for 10 selected oral bacteria using mass spectroscopy and multiplex polymerase chain reaction, respectively. RESULTS: In 60% of patients, deterioration of the oral status (demonstrated by the increase in PI) was recorded (p < 0.05). Moreover, the changes in PI correlated with those of GI (p < 0.001). At the T1 time point, the mean representation of Actinomyces sp. in the total prokaryotic DNA in GCF and dental plaque of individual patients increased compared to T0 (p < 0.05). The probability of finding any of the 7 selected periodontal bacteria combined with Candida sp. was 10 times higher in patients in whom PI deteriorated between T0 and T1 (p < 0.01). CONCLUSIONS: Changes in the oral microbial diversity and an increase in PI were observed in the medium term after bonding of orthodontic appliance. Our study highlights the importance of a complex approach in this type of research as the association between clinical characteristics and combined microbial parameters is higher than when evaluated separately.


Assuntos
Placa Dentária , Microbiota , Humanos , Placa Dentária/microbiologia , Índice de Placa Dentária , Aparelhos Ortodônticos/efeitos adversos , Aparelhos Ortodônticos Fixos/efeitos adversos , Projetos Piloto , Candida
5.
Med Mycol ; 59(10): 1032-1040, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34169983

RESUMO

In recent years, increased rates of yeast infections in humans and animals have been recognized worldwide. Since animals may represent a source of yeast infections for humans, knowing the antifungal susceptibility profile of yeast isolates from milk and evaluating their pathogenic potential would be of great medical importance. Therefore, the aim of this survey was to study yeast diversity in milk samples, analyze the hemolytic and phospholipase activities of isolates and determine minimal inhibition concentration (MIC) for fluconazole, voriconazole and flucytosine. Out of 66 yeast isolates obtained from 910 individual raw milk samples from subclinically infected cows, 26 different yeast species were determined based on sequencing of the D1/D2 and ITS regions. Among them, Pichia kudriavzevii (formerly known as Candida krusei), Kluyveromyces marxianus (formerly known as Candida kefyr) and Debaryomyces hansenii (formerly known as Candida famata) were the most commonly identified. Hemolysin and/or phospholipase activity was observed in 66.7% of isolates. The elevated MIC for fluconazole was determined in 16 isolates from 11 species. The findings of this study demonstrate that yeast isolates from raw milk have the potential to express virulence attributes such as hemolysin and phospholipase, and additionally, some of these strains showed elevated MIC to fluconazole or to flucytosine. LAY SUMMARY: We identified 66 yeast isolates, including 26 different yeast species from 910 individual milk samples. Our results indicate that individual milk samples may serve as a source of yeasts with the potential to trigger infection and may have reduced sensitivity to tested antifungal agents.


Assuntos
Antifúngicos , Fatores de Virulência , Animais , Antifúngicos/farmacologia , Bovinos , Feminino , Fluconazol/farmacologia , Testes de Sensibilidade Microbiana/veterinária , Leite , Fatores de Virulência/genética , Voriconazol
6.
Microb Pathog ; 149: 104394, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32707317

RESUMO

Candidiasis is the most common fungal infection affecting hospitalized patients, especially immunocompromised and critical patients. Limitations regarding the assertive diagnosis of both Candidemia and Candidiasis not only impairs the introduction of effective treatments but also lays a heavy financial burden over the health system. Furthermore, it is still challenging to ascertain whether diagnostic methods are accurate and whether treatment is effective for patients with Candidemia. These constraints come from the uncertainty of the pathophysiological mechanism by which the pathogen establishes the opportunistic infection. Additionally, it is the reason why some patients present positive blood culture results, and others do not, and why it is very difficult during clinical routines to prove Candidemia or invasive candidiasis. Taking into account the current situation, this contribution proposes two markers that may help to understand the mechanisms of infection by the pathogen: Leukotriene F4 and 5,6-dihydroxy-eicosatetraenoic. These two lipids putatively modulate the host's immune response, and the initial data presented in this contribution suggest that these lipids allow the opportunistic infection to be installed. The study was carried out using an omics-based platform using direct-infusion high-resolution mass spectrometry and allied with bioinformatics tools to provide accurate and reliable results for biomarker candidates screening.


Assuntos
Candidemia , Candidíase , Infecções Oportunistas , Antifúngicos/uso terapêutico , Candida , Candidemia/diagnóstico , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Humanos , Leucotrienos
7.
BMC Microbiol ; 19(1): 136, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226938

RESUMO

BACKGROUND: Candidemia is an emerging hospital-acquired bloodstream infection (BSI). It is common among severely ill and immunocompromised patients. Even following appropriate therapy in candidemia, recent studies reveal relative high mortality (40%). The global incidence of candidemia shows an incline. In Sri Lanka, candida speciation often difficult where basic facilities are less available. We have compared the risk factors, epidemiology, demography, and performance of HiChrome Candida differential agar (HiCA) characteristics with the VITEK2 YST platform for differentiation of Candida albicans (CA) and non-albicans candida (NAC) from blood culture isolate. METHODS: This is a laboratory-based cross-sectional study. Positive aerobic BACTEC blood cultures having yeast were identified using HiCA and VITEK2® platform. Epidemiology, risk factors, and clinical outcomes were compared between CA and NAC bloodstream isolates. RESULTS: Out of 120 positive yeast samples, VITEK2® has identified 110 (92%) as Candida sp. From that CA-34 (31%) and NAC-76 (69%) were isolated. Candidemia following NCA in neonates (p = 0.02), infants (p = 0.04) and adults (p = 0.02) in ICU and immunocompromised patients were significantly higher. Compared to CA, NAC bacteremia period prevalence (0.00041%) and incidence (0.23 per 100,000-person-years) was significantly high (p = 0.03). NAC 48 (63%) isolates were resistance to azoles. Exposure to antifungals (odds ratio (OR); p = 0.03), prolonged intensive care stay > 14 days (OR-3.3; p = 0.04), having a central venous line for > 8 days (OR-4.3; p = 0.03) and on immunosuppressive treatment (OR-2.4; p = 0.04) was significantly poses risk for NAC candidemia. Sen day mortality was significant among non-albicans cases (p = 0.03) while 30-day mortality was significant among albicans cases (p = 0.04). Compared to VITEK2®, the HiCA method was 93% sensitive and 93% specific in detecting CA. CONCLUSION: Compared to CA, candidemia following NAC was high. NAC isolates were having a high percentage of fluconazole and voriconazole resistance. VITEK2 YST® platform provides antifungal susceptibility with minimal inhibitory concentration (MIC). Impact, this would highlight the use of rapid candida identification flat form with MIC to direct appropriate antifungals for candidemia. For that implementation of novel diagnostic facilities like the VITEK2 YST platform at a tertiary care facility is demanding.


Assuntos
Antifúngicos/farmacologia , Hemocultura/métodos , Candida/classificação , Candidemia/epidemiologia , Infecção Hospitalar/epidemiologia , Idoso , Hemocultura/instrumentação , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidemia/microbiologia , Infecção Hospitalar/microbiologia , Estudos Transversais , Feminino , Hospitais de Ensino , Humanos , Incidência , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Sensibilidade e Especificidade , Sri Lanka/epidemiologia
8.
BMC Complement Altern Med ; 19(1): 6, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30612544

RESUMO

BACKGROUND: Candida sp. represent the most common cause of fungal infections worldwide. In the present work, we have evaluated the activity of an essential oil extracted from pistachio hulls against a number of standard and clinical strains of Candida sp. METHODS: C. albicans ATCC 64550, C. parapsilosis ATCC 22019, 4 clinical strains of C. albicans, 3 clinical strains of C. parapsilosis and 3 clinical strains of C. glabrata were used. All clinical isolates were identified by species-specific PCR-based methods. Susceptibility studies were performed using pistachio hull essential oil alone or in combination with antifungal compounds. The interactions between pistachio hull essential oil and selected antifungal compounds were also evaluated using the checkerboard method and the mechanisms of interaction investigated by droplet size distribution. RESULTS: Pistachio hull essential oil was fungicidal at the concentrations between 2.50 and 5.0 mg/ml. D-limonene and 3-Carene were the components with major activity. An antagonistic effect was observed with all combinations tested. CONCLUSION: The antifungal activity of pistachio hull essential oil could be used to help control resistance in Candida species. More studies need to be performed to elucidate the mechanisms responsible for the activity of pistachio hull essential oil.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Óleos Voláteis/farmacologia , Pistacia/química , Óleos de Plantas/farmacologia , Candidíase/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos de Plantas/química
9.
Molecules ; 24(10)2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31117281

RESUMO

Candida biofilm structure is particularly difficult to eradicate, since biofilm is much more resistant to antifungal agents than planktonic cells. In this context, a more effective strategy seems to be the prevention of biofilm formation than its eradication. The aim of the study was to examine whether the process of initial colonization of materials (glass, polyethylene terephthalate, polypropylene) by food-borne Candida sp. can be impeded by clove and thyme essential oils, used at their minimal inhibitory concentrations. In the presence of clove oil, 68.4-84.2% of the yeast tested showed a statistically significant reduction in biofilm formation, depending on the material. After treatment with thyme oil, statistically significant decrease in biofilm cell numbers was observed for 63.2-73.7% of yeasts. Confocal laser scanning microscopy showed diverse compounds of clove and thyme oils that were disparately located in C. albicans cell, on a cell wall and a cell membrane, in cytoplasm, and in vacuoles, depicting the multidirectional action of essential oils. However, essential oils that were used in sub-inhibitory concentration were sequestrated in the yeast vacuoles, which indicate the activation of Candida defense mechanisms by cell detoxification. Clove and thyme essential oils due to their anti-biofilm activity can be efficiently used in the prevention of the tested abiotic surfaces colonization by Candida sp.


Assuntos
Biofilmes/efeitos dos fármacos , Óleos Voláteis/farmacologia , Syzygium/química , Thymus (Planta)/química , Antifúngicos/química , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Parede Celular/efeitos dos fármacos , Óleo de Cravo/química , Óleo de Cravo/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia
10.
Trop Anim Health Prod ; 50(2): 421-425, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29080936

RESUMO

Systemic fungal diseases are the infections caused by false treatment protocols and generally are not taken into consideration especially in the veterinary field. One-humped camels are found in the western side of the Aegean region of our country and bred for wrestling. The aim of this study is the application of diagnosing systemic fungi infection from camel blood samples by the PCR method. In this study, specific primers for DNA topoisomerase II gene sequences were used. As a result, a systemic fungal infection was detected by the nested PCR method from 10 (20%) out of 50 DNA samples taken from camels located on the western side of the Aegean region. In this study, 3 (30%) samples were identified as Candida albicans, 3 (30%) samples were identified as C. glabrata, and 4 (40%) samples were identified as C. parapsilosis. In conclusion, the 20% positive systemic fungal infection rate in one-humped camels observed in the present study showed that the systemic fungal infections are not taken into considerations in veterinary medicine. Further studies are suggested in order to obtain and to maintain extensive data for systemic fungal diseases in our country for one-humped camels.


Assuntos
Camelus/microbiologia , Candida/isolamento & purificação , Candidíase/veterinária , Animais , Candidíase/microbiologia , Primers do DNA , Masculino , Reação em Cadeia da Polimerase
11.
Ecotoxicol Environ Saf ; 139: 472-480, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28214644

RESUMO

This study focused on rhizospheric yeast capable of degrading a priority pollutant, 4-nitroaniline (4-NA), under drought stress. Candida sp. AVGB4 (AVGB4) inhabiting in soil was isolated and characterized with plant-growth promoting (PGP) traits. 4-NA-dependent growth kinetic and biodegradation kinetics were analyzed and revealed 4-NA complete degradation and tolerance property. AVGB4 proliferation, PGP activities, and 4-NA degradation activity were well maintained under drought stress induced by PEG-6000 incorporation, and could be strengthened in the presence of succinate, an organic compound generally found in plant root exudates. The in vitro experiments proved that AVGB4 significantly enhanced plant growth and increased the shoot and root biomass of Vigna radiata plant in the absence or presence of 4-NA. The overall results including cytogenotoxicity and phytotoxicity test with legumes indicated that not only AVGB4 was capable of 4-NA detoxification facilitating plants to cope with chemical-toxicity stress, but it also has advantageous role in promoting plant growth and sustainable rhizoremediation of 4-NA contaminated sites.


Assuntos
Compostos de Anilina/metabolismo , Candida/metabolismo , Fabaceae/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biomassa , Candida/isolamento & purificação , Candida/fisiologia , Desidratação , Secas , Microbiologia do Solo
12.
Bioprocess Biosyst Eng ; 40(9): 1411-1418, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28612166

RESUMO

Polycyclic aromatic hydrocarbon is a toxic recalcitrant environmental pollutant and its removal from the environment is very essential. In this study, a novel S1 strain isolated from the tropical rain forest was identified as Candida species based on 18S rRNA. The pyrene biodegradation was performed by Candida sp. S1. Pyrene was 35% degraded in 15 days. The percentage of pyrene biodegradation increased up to 75% with 24 g L-1 of sodium chloride and decreased along with increasing salinity. Under the acidic condition, the biodegradation was increased up to 60% at pH 5. It was also found that the increasing glucose concentration of more than 10 g L-1 had no significant effect on pyrene biodegradation, while agitation proved to have greater influence. There was a positive relationship between biomass growth and biodegradation rate of pyrene. One pyrene metabolite was identified from the extract solution and analyzed by a thin-layer chromatography, UV-visible absorption and gas chromatography-mass spectrometry. The metabolite found in the pyrene degradation was benzoic acid. Suitable conditions must be found to promote a successful microbial augmentation in liquid culture.


Assuntos
Candida/crescimento & desenvolvimento , Pirenos/metabolismo , Meios de Cultura/química , Concentração de Íons de Hidrogênio
13.
Molecules ; 22(7)2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28677650

RESUMO

This work describes the isolation and structural elucidation of compounds from the leaves of Myrcia tomentosa (Aubl.) DC. (goiaba-brava) and evaluates the antimicrobial activity of the crude extract, fractions and isolated compounds against bacteria and fungi. Column chromatography was used to fractionate and purify the extract of the M. tomentosa leaves and the chemical structures of the compounds were determined using spectroscopic techniques. The antibacterial and antifungal activities were assessed using the broth microdilution method. The phytochemical investigation isolated 11 compounds: α-bisabolol, α-bisabolol oxide B, α-cadinol, ß-sitosterol, n-pentacosane, n-tetracosane, quercetin, kaempferol, avicularin, juglanin and guaijaverin. The crude ethanolic extract and its fractions were tested against 15 bacteria and 9 yeasts. The crude extract inhibited the in vitro growth of yeasts at concentration of 4 to 32 µg/mL. The hexane, dichloromethane, ethyl acetate and aqueous fractions inhibited Candida sp. at concentrations of 4 to 256 µg/mL, whereas the Cryptococcus sp. isolates were inhibited only by the hexane and dichloromethane fractions in minimal inhibitory concentrations (MICs) at 16 to 64 µg/mL. The flavonoid quercetin-3-O-α-arabinofuranose (avicularin) was the most active compound, inhibiting Candida species in concentrations of 2 to 32 µg/mL. The MIC values suggest potential activity of this plant species against yeast.


Assuntos
Antifúngicos/farmacologia , Myrtaceae/química , Compostos Fitoquímicos/farmacologia , Antifúngicos/análise , Antifúngicos/química , Candida/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Extratos Vegetais/química , Folhas de Planta/química
14.
Med Mycol ; 54(6): 600-4, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27118806

RESUMO

The epidemiology of invasive fungal infections has recently changed in immunosuppressed populations as a result of HIV infection, organ transplant, chemotherapy and in elderly patients. The diagnosis of invasive fungal infections by culture is prolonged since fungi grow slowly in vitro. we wanted to estimate the frequency of fungemia diagnoses established through the Clinical Mycology Laboratory over the past 10 years; through a retrospective study; data was obtained from the laboratory patient registry in the Infectious Disease Hospital's laboratory registry of patients with a systemic fungal isolate between 2005 and 2014. One hundred and thirty two (132) systemic fungal infections were identified. They were more prevalent in males, in the age group between 20 and 59 years and in patients with a diagnosis of AIDS. The most frequently isolated agents belonged to the genus Candida and others such as Histoplasma sp., Cryptococcus sp., Aspergillus sp., and Coccidioides sp. Of all blood and bone marrow cultures received 17.9% had fungal development; of these, in 70% of cases it was through blood cultures. In general, fungal agents were not diagnostically suspected. We identified that Sixty percent (60%) of fungemias developed in AIDS patients, followed by patients with sepsis. The most common agents belonged to the genus Candida, predominantly the albicans species. They were more frequently identified by blood culture than by bone marrow culture. Invasive fungal infections have not followed a usual clinical pattern and are not easily recognizable.


Assuntos
Fungemia/epidemiologia , Fungos/classificação , Fungos/isolamento & purificação , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Hospitais , Humanos , Lactente , Recém-Nascido , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Adulto Jovem
15.
BMC Infect Dis ; 16(1): 433, 2016 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-27544427

RESUMO

BACKGROUND: Candidemia is an increasing problem in tertiary care hospitals worldwide. Here, we report the first outbreak of candidemia caused by fluconazole-resistant C. parapsilosis (FRCP) strains in Brazil. METHODS: This was a cross-sectional study of clinical and microbiological data of all candidemic episodes diagnosed from July 2011 to February 2012 in a 200-bed tertiary care hospital. Initial yeast identification and susceptibility testing were performed using the VITEK 2 - System. Isolates of Candida spp. resistant to fluconazole were sent to a reference laboratory (LEMI-UNIFESP) for further molecular identification and confirmation of resistance by CLSI microdilution test. A multivariate analysis was conducted to identify factors associated with FRCP infection. RESULTS: We identified a total of 40 critically ill patients with candidemia (15 women) with a median age of 70 years. The incidence of candidemia was 6 cases/1,000 patients admissions, including 28 cases (70 %) of infection with C. parapsilosis, 21 of which (75 %) were resistant to fluconazole. In only 19 % of FRCP candidemia cases had fluconazole been used previously. The results of our study indicated that diabetes is a risk factor for FRCP candidemia (p = 0.002). Overall, mortality from candidemia was 45 %, and mortality from episodes of FRCP infections was 42.9 %. CONCLUSIONS: The clustering of incident cases in the ICU and molecular typing of strains suggest horizontal transmission of FRCP. Accurate vigilant monitoring for new nosocomial strains of FRCP is required.


Assuntos
Antifúngicos , Candidemia/microbiologia , Surtos de Doenças , Farmacorresistência Fúngica , Fluconazol , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Candida , Candidemia/epidemiologia , Infecção Hospitalar/microbiologia , Estudos Transversais , Feminino , Hospitais , Humanos , Incidência , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Fatores de Risco , Adulto Jovem
16.
Mycoses ; 59(5): 281-90, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26864989

RESUMO

This study aimed to investigate the influence of tetraconazole and malathion, both used in agricultural activities, on resistance to fluconazole, itraconazole and voriconazole in Candida parapsilosis ATCC 22019. The susceptibility to tetraconazole, malathion, fluconazole, itraconazole and voriconazole, through broth microdilution. Then, 12 independent replicates, were separated and exposed to four treatment groups, each one containing three replicates: G1: tetraconazole; G2: malathion; G3: fluconazole (positive control); G4: negative control. Replicates from G1, G2 and G3, were exposed to weekly increasing concentrations of tetraconazole, malathion and fluconazole, respectively, ranging from MIC/2 to 32 × MIC, throughout 7 weeks. The exposure to tetraconazole, but not malathion, decreased susceptibility to clinical azoles, especially fluconazole. The tetraconazole-induced fluconazole resistance is partially mediated by the increased activity of ATP-dependent efflux pumps, considering the increase in antifungal susceptibility after the addition of the efflux pump inhibitor, promethazine, and the increase in rhodamine 6G efflux and CDR gene expression in the G1 replicates. Moreover, MDR expression was only detected in G1 and G3 replicates, suggesting that MDR pumps are also involved in tetraconazole-induced fluconazole resistance. It is noteworthy that tetraconazole and fluconazole-treated replicates behaved similarly, therefore, resistance to azoles of clinical use may be a consequence of using azoles in farming activities.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Clorobenzenos/farmacologia , Fluconazol/farmacologia , Fungicidas Industriais/farmacologia , Triazóis/farmacologia , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Antialérgicos/farmacologia , Candida/genética , Resistência Microbiana a Medicamentos , Ergosterol/análise , Regulação Fúngica da Expressão Gênica , Humanos , Itraconazol/farmacologia , Malation/farmacologia , Testes de Sensibilidade Microbiana , Prometazina/farmacologia , Rodaminas , Esterol 14-Desmetilase/genética , Voriconazol/farmacologia
17.
Nanomedicine ; 12(8): 2395-2404, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27464757

RESUMO

This study was designed to assess the antifungal/anti-biofilm and hemolytic properties of two polyene antibiotics, amphotericin B (AMF) and nystatin (NYS), attached to the surface of magnetic nanoparticles (MNP) against clinical isolates of Candida species and human red blood cells, respectively. The developed nanosystems, MNP@AMF and MNP@NYS, displayed stronger fungicidal activity than unbound AMF or NYS. Synergistic activity was observed with a combination of polyenes and MNPs against all tested Candida strains. Nanosystems were more potent than unbound agents when tested against Candida strains in the presence of pus, and as agents able to prevent Candida biofilm formation. The observed inactivation of catalase Cat1 in Candida cells upon treatment with the nanosystems suggests that disruption of the oxidation-reduction balance is a mechanism leading to inhibition of Candida growth. The significant decrease of polyenes lytic activity against host cells after their attachment to MNPs surface indicates improvement in their biocompatibility.


Assuntos
Anfotericina B/administração & dosagem , Antibacterianos/administração & dosagem , Nanopartículas de Magnetita , Polienos/administração & dosagem , Antifúngicos , Sistemas de Liberação de Medicamentos , Humanos , Testes de Sensibilidade Microbiana
18.
J Fungi (Basel) ; 10(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38667939

RESUMO

Candidemia is one of the healthcare-associated infections that has high mortality. The risk factors that predispose a patient to develop this infection are mostly found in patients of greater severity and COVID-19 contributes to the risk of death. The aim of this study is to evaluate epidemiological characteristics and risk factors for mortality in patients with candidemia before and during the COVID-19 pandemic era. This is a retrospective study conducted at Instituto Central from 2016 to 2020 of patients with candidemia that were evaluated for demographic data, medical history, risk factors, microbiological data, therapeutic measures, complementary exams, device management, and outcome defined by 30-day mortality. A total of 170 episodes were included (58.2% males; mean age of 56 years). The overall incidence density of candidemia per 1000 admissions and per 1000 patient-days was 1.17 and 0.17, respectively, with an increase of 38% in the year 2020. The use of a central venous catheter was the most prevalent (93.5%) condition, followed by the previous use of antibiotics (91.1%). Corticosteroid use ranked seventh (56.4%). C. albicans was responsible for 71 (41.7%) of the isolates, followed by C. tropicalis and C. glabrata, with 34 (20%) isolates each. Echinocandin was prescribed in 60.1% of cases and fluconazole in 37%. Echocardiography resulted in six (5.08%) cases of endocarditis and fundoscopy resulting in two (2.4%) endophthalmitis. The 30-day mortality was 93/170 (54.7%). The risk factors associated with mortality were age (OR 1.03, CI 95% 1.01-1.06), heart disease (OR 7.51, CI 95% 1.48-37.9), hemodialysis (OR 3.68, CI 95% 1.28-10.57), and use of corticosteroids (OR 2.83, CI 95% 1.01-7.92). The COVID-19 pandemic had an impact on the increase incidence of candidemia. The persistently high mortality highlights the need for better management strategies, control of risk factors, and guarantee of adequate treatment.

19.
Braz J Microbiol ; 55(3): 2119-2130, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38954220

RESUMO

Biosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical applications. This study focuses on producing, purifying, and characterizing a glycolipid biosurfactant from Candida sp. UFSJ7A, particularly for its application in biofilm prevention on siliconized latex catheter surfaces. The glycolipid was extracted and characterized, revealing a critical micellar concentration (CMC) of 0.98 mg/mL, indicating its efficiency at low concentrations. Its composition, confirmed through Fourier transform infrared spectroscopy (FT-IR) and thin layer chromatography (TLC), identified it as an anionic biosurfactant with a significant ionic charge of -14.8 mV. This anionic nature contributes to its biofilm prevention capabilities. The glycolipid showed a high emulsification index (E24) for toluene, gasoline, and soy oil and maintained stability under various pH and temperature conditions. Notably, its anti-adhesion activity against biofilms formed by Escherichia coli, Enterococcus faecalis, and Candida albicans was substantial. When siliconized latex catheter surfaces were preconditioned with 2 mg/mL of the glycolipid, biofilm formation was reduced by up to 97% for E. coli and C. albicans and 57% for E. faecalis. These results are particularly significant when compared to the efficacy of conventional surfactants like SDS, especially for E. coli and C. albicans. This study highlights glycolipids' potential as a biotechnological tool in reducing biofilm-associated infections on medical devices, demonstrating their promising applicability in healthcare settings.


Assuntos
Biofilmes , Candida , Catéteres , Glicolipídeos , Tensoativos , Glicolipídeos/farmacologia , Glicolipídeos/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Tensoativos/farmacologia , Tensoativos/química , Candida/efeitos dos fármacos , Candida/fisiologia , Catéteres/microbiologia , Látex/química , Látex/farmacologia , Escherichia coli/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia
20.
J Agric Food Chem ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289871

RESUMO

α-Lipoic acid possesses remarkable antioxidant activity; however, its poor lipid solubility greatly restricts its practical utilization. The present study was the first (i) to synthesize a novel lipophilic antioxidant of octacosanol lipoate and (ii) to assess its antioxidant potency in sunflower oil by hydrogen nuclear magnetic resonance (1H NMR) spectroscopy. In brief, octacosanol lipoate was successfully synthesized using octacosanol and lipoic acid as substrates and Candida sp. 99-125 lipase as a catalyst. The conversion of octacosanol lipoate could reach as high as 98.1% within merely 2 h, with an overall yield of 87.9%. The hydrophobicity of lipoic acid was significantly enhanced upon esterification with octacosanol. Interestingly, both traditional methods and 1H NMR analysis consistently indicated that octacosanol lipoate exhibited superior antioxidant activity compared with butyl hydroxytoluene at high temperatures. It was concluded that octacosanol lipoate has the potential to be developed into a safe and efficient natural antioxidant which can be utilized not only in daily cooking oils but also in frying oils.

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