Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Clin Transl Immunology ; 10(4): e1268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968404

RESUMO

OBJECTIVES: Adoptive cell therapy (ACT) with mature T cells modified with a chimeric antigen receptor has demonstrated improved outcome for B-cell malignancies. However, its application for others such as Hodgkin lymphoma remains a clinical challenge. CD30 antigen, expressed in Hodgkin lymphoma cells, is absent in most healthy tissues, representing an ideal target of ACT for this disease. Despite that, efficacy of CD30-chimeric antigen receptor (CAR) T cells for Hodgkin lymphoma remains modest. Here, we have developed and tested a novel CD30-CAR T to improve efficacy of CD30-CAR therapy, using a targeting epitope within the non-cleavable part of CD30 receptor, and memory stem T cells (TSCM) to improve engraftment, persistence and antitumor activity. METHODS: TSCM-like cultures were generated and expanded ex vivo and transduced at day 1 or 2 with a lentiviral vector encoding the CD30-CAR. Therapeutic in vivo experiments were performed using NSG mice injected with L540 (sc) or L428 (iv) and treated with CD30-CAR T cells when the tumor was established. RESULTS: CD30-CAR TSCM-like cells generated and expanded ex vivo, despite CD30 expression and fratricide killing of CD30+ CAR T cells, were not impaired by soluble CD30 and completely eradicated Hodgkin lymphoma in vivo, showing high persistence and long-lasting immunity. In addition, highly enriched CD30-CAR TSCM-like products confer a survival advantage in vivo, in contrast to more differentiated CAR T cells, with higher tumor infiltration and enhanced antitumor effect. CONCLUSION: This study supports the use of a refined CD30-CAR T cells with highly enriched TSCM-like products to improve clinical efficacy of CAR T for Hodgkin lymphoma.

2.
J Neurooncol ; 148(3): 545-554, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32524392

RESUMO

INTRODUCTION: To assess the management of immunocompetent patients with primary central nervous system lymphomas (PCNSL) in Spain. METHODS: Retrospective analysis of 327 immunocompetent patients with histologically confirmed PCNSL diagnosed between 2005 and 2014 in 27 Spanish hospitals. RESULTS: Median age was 64 years (range: 19-84; 33% ≥ 70 years), 54% were men, and 59% had a performance status (PS) ≥ 2 at diagnosis. Median delay to diagnosis was 47 days (IQR 24-81). Diagnostic delay > 47 days was associated with PS ≥ 2 (OR 1.99; 95% CI 1.13-3.50; p = 0.016) and treatment with corticosteroids (OR 2.47; 95% CI 1.14-5.40; p = 0.023), and it did not improve over the years. Patients treated with corticosteroids (62%) had a higher risk of additional biopsies (11.7% vs 4.0%, p = 0.04) but corticosteroids withdrawal before surgery did not reduce this risk and increased the diagnostic delay (64 vs 40 days, p = 0.04). Median overall survival (OS) was 8.9 months [95% CI 5.9-11.7] for the whole series, including 52 (16%) patients that were not treated, and 14.1 months (95%CI 7.7-20.5) for the 240 (73.4%) patients that received high-dose methotrexate (HD-MTX)-based chemotherapy. Median OS was shorter in patients ≥ 70 years (4.1 vs. 13.4 months; p < 0.0001). Multivariate analysis identified age ≥ 65 years, PS ≥ 2, no treatment, and cognitive/psychiatric symptoms at diagnosis as independent predictors of short survival. CONCLUSIONS: Corticosteroids withdrawal before surgery does not decrease the risk of a negative biopsy but delays diagnosis. In this community-based study, only 73.4% of patients could receive HD-MTX-based chemotherapy and OS remains poor, particularly in elderly patients ≥ 70 years.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Nervoso Central/mortalidade , Quimiorradioterapia/mortalidade , Irradiação Craniana/mortalidade , Diagnóstico Tardio/estatística & dados numéricos , Imunocompetência , Linfoma não Hodgkin/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carmustina/administração & dosagem , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/imunologia , Neoplasias do Sistema Nervoso Central/terapia , Citarabina/administração & dosagem , Feminino , Seguimentos , Humanos , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/terapia , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
3.
Ann Hematol ; 99(7): 1627-1634, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451707

RESUMO

There is no standard treatment for relapsed follicular lymphoma (FL). Although platinum-based combinations are one of the most used treatments, few data have been reported in this setting. Our aim was to analyse R-ESHAP efficacy in relapsed FL patients. We retrospectively analysed 80 FL patients treated with R-ESHAP in the first or successive relapses. Responding patients received a stem cell transplantation following R-ESHAP. Seventeen histologically transformed patients were included. Median age was 50 years. At R-ESHAP initiation, 85% of the patients were in an advanced stage, 28% had a bulky disease and 40% had increased LDH. There were no statistically significant differences between POD24 and non-POD24 patients in terms of response to R-ESHAP (ORR 72% vs. 93%, p = 0.109). When analyzing R-ESHAP efficacy according to the response to the immediately previous line, patients achieving CR or PR had better CR rates to R-ESHAP than those who did not respond (CR of 57% vs. 15%, respectively, p = 0.009), as well as differences in OS (7.2 vs. 1.4 years, p < 0.0001) and in PFS (2.1 vs. 0.3 years, p < 0.0001). R-ESHAP is an effective treatment in relapsed FL patients who respond to the previous line and has to be considered as an adequate alternative for some patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/patologia , Rituximab/administração & dosagem , Terapia de Salvação/métodos , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Linfoma Folicular/mortalidade , Masculino , Metilprednisolona/administração & dosagem , Metilprednisolona/efeitos adversos , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva , Estudos Retrospectivos , Rituximab/efeitos adversos , Espanha/epidemiologia , Análise de Sobrevida , Falha de Tratamento , Resultado do Tratamento , Adulto Jovem
4.
J Appl Microbiol ; 126(5): 1414-1425, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30729620

RESUMO

AIMS: A culture medium based on apple bagasse was designed and tested as a substrate for biomass production of conventional and unconventional native wine yeasts. METHODS AND RESULTS: The physicochemical characterization of the apple bagasse was carried out and its potential utility as a constituent of a complete culture medium for the production of yeast biomass was analysed using the experimental statistical designs. Growth parameters of conventional and nonconventional Patagonian wine yeasts were analysed with Placket-Burman designs and response surface methodology, comparing in each assay the apple bagasse substrate with the commonly used substrate for biomass development, cane molasses. Culture media composition was optimized and models were validated. CONCLUSIONS: This study demonstrates that, both from a nutritional and from an economic point of view, apple bagasse constitutes a more advantageous substrate than cane molasses for the propagation of native yeasts from Patagonia. SIGNIFICANCE AND IMPACT OF THE STUDY: We used an alternate carbon-rich material, generously available in our region, originally generated as fruit industrial waste, to transform it into a source of sustainable, economically profitable and environmentally friendly energy resource.


Assuntos
Biomassa , Celulose , Malus , Vinho/microbiologia , Leveduras , Celulose/química , Celulose/metabolismo , Meios de Cultura/química , Meios de Cultura/metabolismo , Malus/química , Malus/metabolismo , Melaço , Leveduras/química , Leveduras/metabolismo
5.
J Appl Microbiol ; 117(2): 451-64, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24844932

RESUMO

AIMS: The purpose of this study was to select autochthonous yeasts with metabolic ability to degrade L-malic acid for its potential use in young wine deacidification. METHODS AND RESULTS: Fifty seven Patagonian nonSaccharomyces yeast of oenological origin were identified by conventional molecular methods and tested in their capability to grow at the expense of L-malic acid. Only four isolates belonging to Pichia kudriavzevii species showed this property, and one of them was selected to continue with the study. This isolate, named as P. kudriavzevii ÑNI15, was able to degrade L-malic acid in microvinifications, increasing the pH 0·2-0·3 units with a minimal effect on the acid structure of wine. Additionally, this isolate produced low levels of ethanol, important levels of glycerol (10·41 ± 0·48 g l(-1) ) and acceptable amounts of acetic acid (0·86 ± 0·13 g l(-1) ). In addition, it improved the sensorial attributes of wine increasing its fruity aroma. CONCLUSIONS: The selection of yeasts for oenological use among nonSaccharomyces species led to the finding of a yeast strain with novel and interesting oenological characteristics which could have significant implications in the production of well-balanced and more physicochemical and microbiological stable young wines. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of P. kudriavzevii ÑNI15 as mixed starter with S. cerevisiae would eliminate the cultural and cellar operations undertaken to adjust the musts acidity, therefore improving wine quality and reducing production costs.


Assuntos
Malatos/metabolismo , Pichia/metabolismo , Vinho/microbiologia , Fermentação , Concentração de Íons de Hidrogênio , Saccharomyces cerevisiae/metabolismo , Leveduras/isolamento & purificação , Leveduras/metabolismo
6.
J Colloid Interface Sci ; 373(1): 27-33, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21999953

RESUMO

The parameters that control the stability of ZnO-nanoparticles suspensions and their deposition by electrophoretic deposition were studied, so as to organize the assembly and compaction of nanoparticles. The addition of cationic polyelectrolyte - Polyethylenimine (PEI) - with different molecular weights was investigated, in order to study their effectiveness and the influence of the molecular weight of the organic chain on suspensions dispersion. It was found that PEI with the highest molecular weight provided better dispersion conditions. Cathodic EPD was performed under previously optimized suspensions conditions and over electropolished stainless steel substrates. Experimental results showed that the EPD process in these conditions allows obtaining dense transparent ZnO thin films. Deposition times and intensities were optimized by analyzing the resulting thin films characteristics. Finally, the deposits were characterized by FE-SEM, AFM, and different spectroscopic techniques.

7.
J Appl Microbiol ; 109(6): 2206-13, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20860771

RESUMO

AIMS: The purpose of this study was to characterize the α-l-rhamnosidase of Pichia guilliermondii NPCC1053 indigenous wine strain from North-Patagonian region. METHODS AND RESULTS: The optimization of yeast culture conditions was carried out and the effects of oenological parameters on α-l-rhamnosidase activity were evaluated. Additionally, the effect of direct contact with must and wine on α-l-rhamnosidase activity was assayed. This strain showed an intracellular inducible α-l-rhamnosidase activity. This enzyme was active at pH, glucose and SO(2) concentrations usually found at the beginning of the fermentation as well as retained high levels of activity after 24 h of incubation in must. Furthermore, P. guilliermondiiα-l-rhamnosidase was able to release monoterpenols and alcohols from grape glycosidic extracts. CONCLUSIONS: The α-l-rhamnosidase belonging to P. guilliermondii indigenous wine yeast strain showed mainly an intracellular location and evidenced interesting oenological characteristics. SIGNIFICANCE AND IMPACT OF THE STUDY: This study contributes to the knowledge of α-l-rhamnosidases from yeast origin because at present, there are few reports about this enzymatic activity in these micro-organisms. In addition, this work is relevant to the regional wine industry considering that this enzyme could be used in the production of more aromatic young wines.


Assuntos
Glicosídeo Hidrolases/metabolismo , Pichia/enzimologia , Vinho/microbiologia , Argentina , Meios de Cultura , Fermentação , Pichia/crescimento & desenvolvimento
8.
Rev. argent. microbiol ; 39(4): 230-236, oct.-dic. 2007. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-634563

RESUMO

La identificación rápida y segura de los agentes etiológicos y el desarrollo de nuevos antifúngicos con blancos de acción más específicos resultarán en tratamientos de las micosis más efectivos y menos lesivos. Mediante un método molecular rápido (ITS1-5.8S ADNr-ITS2 PCR-RFLP) se identificaron 53 aislamientos de levaduras provenientes de infecciones no sistémicas registradas en hospitales públicos de la ciudad de Neuquén y en un centro oftalmológico de Buenos Aires durante el año 2005. Adicionalmente y utilizando el método de inhibición del crecimiento en placa, se evaluó la sensibilidad de estas levaduras a toxinas killer producidas por levaduras indígenas de la Patagonia y por cepas de referencia. Ocho especies de levaduras fueron identificadas entre los aislamientos clínicos: Candida albicans (52%) , Candida parapsilosis (17%) , Candida tropicalis (10%) , Candida krusei (5%) , Candida glabrata (4%) , Candida guilliermondii (4%) , Kluyveromyces lactis (4%) y Saccharomyces cerevisiae (4%) . El 69% de los aislamientos de la especie mayoritaria, C. albicans, se relacionó con infecciones vaginales. Por otra parte, el 61% de las levaduras provenientes de infecciones oculares correspondió a la especie C. parapsilosis. En las condiciones de ensayo, las toxinas producidas por las levaduras killer indígenas DVMais5 y HCMeiss5 pertenecientes a las especies Pichia anomala y P. kluyveri, respectivamente, exhibieron el mayor espectro de acción sobre las levaduras aisladas de materiales clínicos.


The use of quick and reliable yeast identification methods, as well as the development of new antifungal agents with more specific targets, will enable a more efficient treatment of mycoses. In the present work, a total of 53 clinical isolates obtained from non-systemic infections in Neuquén Hospitals and an ophthalmologic clinic in Buenos Aires during 2005, were identified by means of a rapid molecular method (ITS1-5.8S ADNr-ITS2 PCR-RFLP). Additionally, the killer susceptibility of the isolates was tested against reference and indigenous killer yeasts on plate tests. Eight yeast species were identified among the clinical isolates: Candida albicans (52%), Candida parapsilosis (17%), Candida tropicalis (10%), Candida krusei (5%), Candida glabrata (4%) , Candida guilliermondii (4%) , Kluyveromyces lactis (4%) and Saccharomyces cerevisiae (4%) . Sixty-nine percent of the isolates corresponding to the predominant species ( C. albicans) were related to vaginal infections. On the other hand, 61% of the yeasts associated with ocular infections were identified as C. parapsilosis. Two indigenous killer isolates DVMais5 and HCMeiss5, belonging to Pichia anomala and P. kluyveri respectively, exhibited the broadest killer spectrum against clinical isolates.


Assuntos
Feminino , Humanos , Masculino , Técnicas de Tipagem Micológica , Micoses/microbiologia , Micotoxinas/farmacologia , Proteínas/farmacologia , Leveduras/isolamento & purificação , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidíase Vulvovaginal/microbiologia , Candidíase/microbiologia , Farmacorresistência Fúngica , Infecções Oculares Fúngicas/microbiologia , Fatores Matadores de Levedura , Kluyveromyces/efeitos dos fármacos , Kluyveromyces/isolamento & purificação , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/isolamento & purificação , Leveduras/efeitos dos fármacos
9.
Rev Argent Microbiol ; 39(4): 230-6, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-18390160

RESUMO

Rapid identification and susceptibility to killer toxins of yeasts isolated from non-systemic mycoses. The use of quick and reliable yeast identification methods, as well as the development of new antifungal agents with more specific targets, will enable a more efficient treatment of mycoses. In the present work, a total of 53 clinical isolates obtained from non-systemic infections in Neuquén Hospitals and an ophthalmologic clinic in Buenos Aires during 2005, were identified by means of a rapid molecular method (ITS1-5.8S ADNr-ITS2 PCR-RFLP). Additionally, the killer susceptibility of the isolates was tested against reference and indigenous killer yeasts on plate tests. Eight yeast species were identified among the clinical isolates: Candida albicans (52%), Candida parapsilosis (17%), Candida tropicalis (10%), Candida krusei (5%), Candida glabrata (4%), Candida guilliermondii (4%), Kluyveromyces lactis (4%) and Saccharomyces cerevisiae (4%). Sixty-nine percent of the isolates corresponding to the predominant species (C. albicans) were related to vaginal infections. On the other hand, 61% of the yeasts associated with ocular infections were identified as C. parapsilosis. Two indigenous killer isolates DVMais5 and HCMeiss5, belonging to Pichia anomala and P. kluyveri respectively, exhibited the broadest killer spectrum against clinical isolates.


Assuntos
Técnicas de Tipagem Micológica , Micoses/microbiologia , Micotoxinas/farmacologia , Proteínas/farmacologia , Leveduras/isolamento & purificação , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidíase/microbiologia , Candidíase Vulvovaginal/microbiologia , Farmacorresistência Fúngica , Infecções Oculares Fúngicas/microbiologia , Feminino , Humanos , Fatores Matadores de Levedura , Kluyveromyces/efeitos dos fármacos , Kluyveromyces/isolamento & purificação , Masculino , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/isolamento & purificação , Leveduras/efeitos dos fármacos
10.
Phys Rev Lett ; 94(21): 217206, 2005 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-16090346

RESUMO

In this Letter, we experimentally show that the room temperature ferromagnetism in the Mn-Zn-O system recently observed is associated with the coexistence of Mn(3+) and Mn(4+) via a double-exchange mechanism. The presence of the ZnO around MnO(2) modifies the kinetics of MnO(2)-->Mn(2)O(3) reduction and favors the coexistence of both Mn oxidation states. The ferromagnetic phase is associated with the interface formed at the Zn diffusion front into Mn oxide, corroborated by preparing thin film multilayers that exhibit saturation magnetization 2 orders of magnitude higher than bulk samples.

11.
Nanotechnology ; 16(2): 214-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21727425

RESUMO

The magnetic properties of the system MnZnO prepared by conventional ceramic procedures using ZnO and MnO(2) starting powders are studied and related to the nanostructure. Thermal treatment at 500 °C produces a ferromagnetic phase, although this temperature is not high enough to promote proper sintering; thus the thermally treated compact shows brittle characteristics of unreacted and poorly densified ceramic samples. Scanning electron microscopy and x-ray analysis reveal the appearance of a new phase, most probably related to the diffusion of Zn into MnO(2) oxide nanocrystals. The magnetic properties deviate considerably from what would be expected of an unreacted mixture of ZnO (diamagnetic) and MnO(2) particles (paramagnetic above 100 K and anti-ferromagnetic below that temperature), exhibiting a ferromagnetic like behaviour from 5 to 300 K and beyond mixed with a paramagnetic component. The ferromagnetic phase seems to be originated by diffusion at the nanoscale of Zn into MnO(2) grains. The Curie temperature of the ferromagnetic phase, once the paramagnetic component has been subtracted from the hysteresis loops, is measured to be 450 K. EPR resonance experiments from 100 to 600 K confirm a ferromagnetic to paramagnetic like transition above room temperature for these materials.

12.
J Appl Microbiol ; 96(1): 84-95, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14678162

RESUMO

AIMS: The purpose of this study was to select autochthonous glycosidase producer yeasts with potential use in industrial production of Patagonian red wines. METHODS AND RESULTS: The study was carried out in oenological autochthonous yeasts from Comahue region (Argentinean North Patagonia). A set of screenable yeast phenotypic characteristics indicative of their potential usefulness in more aromatic red wine production was defined and tested in both, Saccharomyces and non-Saccharomyces populations. Twelve isolates showing six different glycosidase phenotypes were selected and they were characterized at species and strain levels using molecular methods. A close correlation between molecular and phenotypic characteristics was observed. Five strains belonging to Candida guilliermondii, C. pulcherrima and Kloeckera apiculata with highest constitutive beta-glucosidase activity levels without anthocyanase activity were discriminated. Some of them also showed constitutive beta-xylosidase and inductive alpha-rhamnosidase activities. CONCLUSIONS: The extension of the selection of oenological yeast to non-Saccharomyces species provided strains possessing novel and interesting oenological characteristics which could have significant implications in the production of more aromatic young red wine. SIGNIFICANCE AND IMPACT OF THE STUDY: As these non-Saccharomyces are indigenous to wine, they can be used in mixed starters at the beginning or as pure cultures at the end fermentation to contribute in enhancing the wine nuance that is typical of this specific area.


Assuntos
Glicosídeo Hidrolases/metabolismo , Vinho/microbiologia , Leveduras/enzimologia , Análise por Conglomerados , DNA Fúngico/genética , Fermentação , Humanos , Microbiologia Industrial , Técnicas de Tipagem Micológica/métodos , Fenótipo , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Espanha , Leveduras/classificação , Leveduras/patogenicidade
13.
J Appl Microbiol ; 93(4): 608-15, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12234344

RESUMO

AIMS: To study the diversity and dynamics of indigenous Saccharomyces wine populations during Malbec spontaneous fermentation, a representative Patagonian red wine, at both industrial and laboratory scale. METHODS AND RESULTS: Two molecular techniques, including restriction fragment length polymorphism of mitochondrial (mt) DNA and polymorphism of amplified delta interspersed element sequences, were used for characterization of indigenous yeasts at strain level. The mtDNA restriction patterns showed the major discriminative power; however, by combining the two molecular approaches it was possible to distinguish a larger number of strains and, therefore, draw more representative conclusions about yeast diversity. Although a great diversity of wild Saccharomyces cerevisiae strains was observed, only nine represented more than half of the total Saccharomyces yeast biota analysed; five of these were common and took over the Malbec must fermentation in both vinifications. CONCLUSIONS: Many different indigenous S. cerevisiae strains were identified; nevertheless, the dominant strains in both industrial and laboratory vinification processes were just a few and the same. SIGNIFICANCE AND IMPACT OF THE STUDY: Small-scale fermentation appears to be a valuable tool in winemaking, one especially helpful in evaluating microbiological aspects of as well as possible interactions between inoculated selected strains and native strains.


Assuntos
Clima Frio , Variação Genética , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Argentina , Elementos de DNA Transponíveis/genética , DNA Fúngico/análise , DNA Mitocondrial/genética , DNA Espaçador Ribossômico/genética , Fermentação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Saccharomyces cerevisiae/crescimento & desenvolvimento
14.
J Basic Microbiol ; 41(2): 105-113, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11441458

RESUMO

The occurrence of killer wine yeasts in Comahue Region (Patagonia, Argentina) was studied. Wild wine yeasts were isolated from spontaneously fermenting Merlot and Malbec type musts. Out of 135 isolates analyzed 37% were sensitive to some well characterized killer toxins as K1-K10 and did not show killer activity (sensitive phenotype, S), 21% showed neutral phenotype (N) and 42% demonstrated killer activity (killer phenotype, K). All but two killer strains, identified as Candida pulcherrima and Kluyveromyces marxianus, were Saccharomyces cerevisiae. Additionally, all killer strains were sensitive to some killer reference strains, showing a killer-sensitive phenotype (KS); neither Saccharomyces or non-Saccharomyces wild yeasts were phenotype killer-resistant (KR). The incidence of the killer character varied with respect to fermentation stage and grape variety, increasing throughout fermentation (13-55% to 36-90%). Irrespective of grape must type, the neutral and sensitive yeasts were ever predominant at initial stages of fermentation. All but six neutral strains, identified as Saccharomyces cerevisiae, were Kloeckera apiculata.


Assuntos
Micotoxinas/metabolismo , Micotoxinas/farmacologia , Vinho/microbiologia , Leveduras/efeitos dos fármacos , Leveduras/metabolismo , Argentina , Fermentação , Fatores Matadores de Levedura , Proteínas de Saccharomyces cerevisiae
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...