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1.
J Agric Food Chem ; 67(37): 10423-10431, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31487168

RESUMO

Plants often produce antifungal peptides and proteins in response to infection. Also wheat, which is the main ingredient of bread dough, contains such components. Here, we show that while some industrial strains of the baker's yeast Saccharomyces cerevisiae can efficiently ferment dough, some other strains show much lower fermentation capacities because they are sensitive to a specific wheat protein. We purified and identified what turned out to be a thaumatin-like protein through a combination of activity-guided fractionation, cation exchange chromatography, reversed-phase HPLC, and LC-MS/MS. Recombinant expression of the corresponding gene and testing the activity confirmed the inhibitory activity of the protein.


Assuntos
Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Triticum/química , Cromatografia Líquida , Fermentação , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Espectrometria de Massas em Tandem , Triticum/genética , Triticum/metabolismo , Triticum/microbiologia
2.
Chem Biol Interact ; 311: 108776, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31369745

RESUMO

Omeprazole (OM), a prototype proton pump inhibitor, oxidizes thiol groups and induces DNA damage. The aim of this study was to evaluate the oxidative effects of omeprazole and its interactions with ascorbic acid (AA, 50 µM) and retinol palmitate (RP) in proficient and deficient Saccharomyces cerevisiae strains, as well as levels of cytogenetic damage in Sarcoma 180 (S180) cells. Omeprazole was tested at concentrations of 10, 20 and 40 µg/mL, whereas H2O2 (10 mM), cyclophosphamide (20 mg/mL), and saline (0.9% NaCl solution) were employed as stressor, positive control, and negative control, respectively. Results revealed that omeprazole concentration-dependently induces oxidative effects in S. cerevisiae strains. However, omeprazole co-treated with ascorbic acid (50 µM) and retinol palmitate (100 IU) significantly modulated the oxidative damage inflected on the S. cerevisiae strains. Furthermore, omeprazole did not produce micronucleus formation and chromosomal bridges in S180 cells, but induced shoots. Significant increase in karyolysis and karyorrhexis were also observed with the omeprazole treated groups, which was modulated by co-treatment with ascorbic acid and retinol palmitate. Taken all together, it is suggested that ascorbic acid and retinol palmitate can substantially modulate the oxidative damage caused by omeprazole on the S. cerevisiae strains, however, much precaution is recommended with omeprazole and antioxidant co-treatment.


Assuntos
Ácido Ascórbico/farmacologia , Aberrações Cromossômicas/efeitos dos fármacos , Omeprazol/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Vitamina A/análogos & derivados , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclofosfamida/toxicidade , Peróxido de Hidrogênio/toxicidade , Camundongos , Testes para Micronúcleos , Vitamina A/farmacologia
3.
World J Microbiol Biotechnol ; 35(9): 136, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432249

RESUMO

Volatile phenols such as 4-ethylphenol are produced from hydroxycinnamic acids by Dekkera bruxellensis, an important yeast contaminating alcoholic fermentations. 4-ethylphenol results from the decarboxylation and reduction of p-coumaric acid, a compound found in sugarcane musts. In wine, volatile phenols are responsible by sensorial alterations whereas in the context of bioethanol fermentation, little is known about their effects on the main yeast, Saccharomyces cerevisiae. Here we evaluated the interaction of 4-ethylphenol and pH, sucrose and ethanol on the growth and fermentation capacity of the industrial strain of S. cerevisiae PE-2. A central compound rotational design was utilized to evaluate the effect of 4-ethylphenol, pH, ethanol and sucrose concentration on the yeast maximum specific growth rate (µmax) in microplate experiments in YPS medium (Yeast extract-Peptone-Sucrose), at 30 °C. Following, single-cycle fermentations in YPS medium, pH 4.5, 17% sucrose, at 30 °C, with 4-ethylphenol in concentrations of 10 and 20 mg L-1 being added at the start or after 4 h of fermentation, were carried out. 4-ethylphenol affected µmax of S. cerevisiae in situations that resemble the conditions of industrial bioethanol production, especially the low pH of the fermentation medium and the high ethanol concentration because of the anaerobic sucrose uptake. The addition of 4-ethylphenol on fermentation resulted in significant effect on the cell yeast concentration, pH and alcohol production, with significant decrease from 86% to the range of 65-74% in the fermentative efficiency. The industrial yeast S. cerevisiae PE-2 growth and fermentative capacity were affected by the presence of 4-ethylphenol, a metabolite produced by D. bruxellensis, which may contribute to explain the impact of this yeast on bioethanol industrial production.


Assuntos
Etanol/metabolismo , Fermentação , Microbiologia Industrial , Fenóis/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Sacarose/metabolismo , Meios de Cultura/química , Inibidores do Crescimento/metabolismo , Concentração de Íons de Hidrogênio , Saccharomyces cerevisiae/efeitos dos fármacos , Temperatura Ambiente
4.
Chemosphere ; 233: 786-795, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340409

RESUMO

Microbial volatile organic compounds (mVCs) are formed in the metabolism of microorganisms and widely distributed in nature and pose threats to human health. However, the air pollution by microorganisms is a situation which is poorly understood. In this study, the cytotoxicity of E. aerogenes VCs was evaluated in the model organism Saccharomyces cerevisiae. E. aerogenes VCs inhibited the survival of yeast and triggered the formation of intracellular reactive oxygen species (ROS). The hypersensitive of MAP kinase mpk1/slt2 and 19S regulatory assembly chaperone adc17 mutants to the E. aerogenes VCs indicated cell wall integrity (CWI) pathway together with stress-inducible proteasome assembly regulation are essentially involved in mVCs tolerance mechanism. Furthermore, exposure to the mVCs resulted in the transcriptional upregulation of the CWI pathway, the regulatory particle assembly chaperones, and genes involved in proteasome regulations. Our research suggested that the ROS/MAPK signaling and proteasome regulatory pathway play pivotal roles in the integration and fine-tuning of the mVCs stress response. This study provides a molecular framework for future study of the effects of mVCs on more complex organisms, such as humans.


Assuntos
Enterobacter aerogenes/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Parede Celular/metabolismo , Citoplasma/metabolismo , Chaperonas Moleculares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ativação Transcricional
5.
Food Chem ; 300: 125174, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31330370

RESUMO

This paper focuses on the use of a new type of yeast encapsulation procedure, applying the chitosan-calcium alginate double layer microcapsules, for the production of Riesling sparkling wine. Four different sparkling wines were produced by free or encapsulated yeasts. The four types of yeast used were adapted (Free EtOH-A, Encapsulated EtOH-A) and non-adapted to ethanol (Free, Encapsulated). The different yeast-inoculating formats had a significant impact on oxygen consumption and pressure increase rate in the bottle during the prise de mousse. Similarly to the free form, encapsulated yeast successfully completed the secondary fermentation. After an ageing period of 6 months, volatiles and sensory profiles of sparkling wines were compared. Although, some differences in volatile profiles were found among samples, sparkling wines produced by Encapsulated EtOH-A showed sensory properties, in terms of aroma, taste and body, similar to those produced by free yeast (both adapted and non-adapted to ethanol).


Assuntos
Alginatos/química , Quitosana/química , Saccharomyces cerevisiae/fisiologia , Vinho/microbiologia , Adulto , Idoso , Cápsulas , Etanol/química , Etanol/farmacologia , Feminino , Fermentação , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes , Pressão , Saccharomyces cerevisiae/efeitos dos fármacos , Paladar , Compostos Orgânicos Voláteis/análise , Vinho/análise
6.
Int J Nanomedicine ; 14: 4801-4816, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308659

RESUMO

Background: Silver nanoparticles (AgNPs) inhibit the proliferation of various fungi; however, their mechanisms of action remain poorly understood. To better understand the inhibitory mechanisms, we focused on the early events elicited by 5 nm AgNPs in pathogenic Candida albicans and non-pathogenic Saccharomyces cerevisiae. Methods: The effect of 5 nm and 100 nm AgNPs on fungus cell proliferation was analyzed by growth kinetics monitoring and spot assay. We examined cell cycle progression, reactive oxygen species (ROS) production, and cell death using flow cytometry. Glucose uptake was assessed using tritium-labeled 2-deoxyglucose. Results: The growth of both C. albicans and S. cerevisiae was suppressed by treatment with 5 nm AgNPs but not with 100 nm AgNPs. In addition, 5 nm AgNPs induced cell cycle arrest and a reduction in glucose uptake in both fungi after 30 minutes of culture in a dose-dependent manner (P<0.05). However, in C. albicans only, an increase in ROS production was detected after exposure to 5 nm AgNPs. Concordantly, an ROS scavenger blocked the effect of 5 nm AgNPs on the cell cycle and glucose uptake in C. albicans only. Furthermore, the growth-inhibition effect of 5 nm AgNPs was not greater in S. cerevisiae mutant strains deficient in oxidative stress response genes than it was in wild type. Finally, 5 nm AgNPs together with a glycolysis inhibitor, 3-bromopyruvate, synergistically enhanced cell death in C. albicans (P<0.05) but not in S. cerevisiae. Conclusion: AgNPs exhibit antifungal activity in a manner that may or may not be ROS dependent, according to the fungal species. The combination of AgNPs with 3-bromopyruvate may be more useful against infection with C. albicans.


Assuntos
Candida albicans/citologia , Ciclo Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Piruvatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/citologia , Prata/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Depuradores de Radicais Livres/farmacologia , Fase G1/efeitos dos fármacos , Genes Fúngicos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
7.
Carbohydr Polym ; 220: 22-29, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31196544

RESUMO

The control of chitosan/silver nanoparticle composite microsphere (CAgMs) size is crucial for tuning its function. In the current work, monodisperse organically-modified CAgMs with controllable size were synthesized using a two-step method. The fine-tuning of the microsphere size was confirmed by many reaction parameters while the cross-linking agent was the key research object. Through physical and thermodynamic analysis, we found the cross-linking agent-induced smaller size, higher silver concentration, more heightened glass transition temperature and stronger hydrogen bond network. The as-prepared microspheres exhibited strong bacteriostasis and fresh-keeping function depending on cross-linking agent concentration. The phenomenon is believed to be derived from the difference in microorganism adsorption and killing ability from induced varying specific surface area and encapsulated silver content. Our current work highlights the size-controllable preparation of CAgMs, and based on our findings, small size CAgMs can be a promising candidate in the field of antibacterial and fruit preservation applications.


Assuntos
Antibacterianos/farmacologia , Quitosana/toxicidade , Conservação de Alimentos/métodos , Malpighiaceae/microbiologia , Nanopartículas Metálicas/toxicidade , Microesferas , Prata/toxicidade , Quitosana/química , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/química , Tamanho da Partícula , Penicillium/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos
8.
Carbohydr Polym ; 219: 414-422, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151542

RESUMO

The bioconversion of rice straw into ethanol can alleviate the energy crisis and solve problems related to waste treatment. In this study, the effect of soluble polysaccharides (SPs) produced during rice straw saccharification on the formation of extracellular matrices (EMs) by the yeast Saccharomyces cerevisiae was investigated. SPs were characterized by high-performance liquid chromatography (HPLC) and fourier transform infrared spectroscopy (FT-IR). SPs reduced the inhibition of alcohol dehydrogenase activity by phenolic acids (PAs) and regulated the intracellular redox state, resulting in higher ethanol production. The results of flow cytometry, confocal laser scanning microscopy, and atomic force microscopy indicated that PAs changed microbial morphology and caused damage in microbial cell membranes. The protective effect of SPs against cell membrane damage could be attributed to the synthesis of polysaccharide-dependent extracellular matrix, which maintained cellular integrity even under phenolic acid stress. These findings provide new strategies to improve pretreatment and saccharification processes.


Assuntos
Membrana Celular , Matriz Extracelular , Oryza/química , Extratos Vegetais , Polissacarídeos/farmacologia , Saccharomyces cerevisiae , Álcool Desidrogenase/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , China , Etanol/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fermentação , Hidrólise , Hidroxibenzoatos/toxicidade , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/química , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo
9.
Int J Food Microbiol ; 304: 75-88, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31174038

RESUMO

Fermented cereal doughs constitute a predominant part of West African diets. The environment of fermented doughs can be hostile for microbial survival due to high levels of microbial metabolites such as weak carboxylic organic acids and ethanol. In order to get a better understanding of the intrinsic factors affecting the microbial successions of yeasts during dough fermentation, survival and physiological responses of the yeasts associated with West African fermented cereal doughs were investigated at exposure to relevant concentrations of microbial inhibitory compounds. Three strains each of the predominant species, i.e. Saccharomyces cerevisiae, Kluyveromyces marxianus, Pichia kudriavzevii as well as the opportunistic pathogen Candida glabrata were studied. The strains were exposed to individual stress factors of cereal doughs, i.e. (i) pH 3.4, (ii) 3% (v/v) ethanol (EtOHpH3.4), (iii) 285 mM lactic acid (LApH3.4) and (iv) 150 mM acetic acid (AApH3.4) as well as to combinations of these stress factors, i.e. (v) (LA + AA)pH 3.4 and (vi) (LA + AA+EtOH)pH 3.4. Growth and single cell viability were studied by flow cytometry using combined SYTO 13 and propidium iodide (PI) staining. Intracellular pH (pHi), plasma membrane integrity and micro-colony development of stressed cells were studied by fluorescence microscopy using PI and carboxyfluorescein diacetate succinimidyl ester (CFDA-se). Viability of the yeast strains was not affected by pH 3.4 and 3% (v/v) ethanol (EtOHpH3.4). 285 mM lactic acid (LApH3.4) reduced the specific growth rate (µmax) from 0.27-0.41 h-1 to 0.11-0.26 h-1 and the viability from 100% to 2.6-41.7% at 72 h of exposure in most yeast strains, except for two strains of C. glabrata. 150 mM acetic acid (AApH3.4) as well as the combinations (LA + AA)pH 3.4 and (LA + AA+EtOH)pH 3.4 reduced µmax to 0.0 h-1 and induced significant cell death for all the yeast strains. Exposed to (LA + AA+EtOH)pH 3.4, the most resistant yeast strains belonged to S. cerevisiae followed by P. kudriavzevii, whereas C. glabrata and K. marxianus were more sensitive. Strain variations were observed within all four species. When transferred to non-stress conditions, i.e. MYGP, pH 5.6, after exposure to (LA + AA+EtOH)pH 3.4 for 6 h, 45% of the single cells of the most resistant S. cerevisiae strain kept their plasma membrane integrity, recovered their pHi to near physiological range (pHi = 6.1-7.4) and resumed proliferation after 3-24 h of lag phase. The results obtained are valuable in order to change processing conditions of the dough to favor the survival of preferable yeast species, i.e. S. cerevisiae and K. marxianus and inhibit opportunistic pathogen yeast species as C. glabrata.


Assuntos
Candida/efeitos dos fármacos , Grão Comestível/microbiologia , Alimentos Fermentados/microbiologia , Kluyveromyces/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Pichia/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Ácido Acético/farmacologia , Reatores Biológicos , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Etanol/farmacologia , Fermentação , Kluyveromyces/crescimento & desenvolvimento , Kluyveromyces/isolamento & purificação , Ácido Láctico/farmacologia , Pichia/crescimento & desenvolvimento , Pichia/isolamento & purificação , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/isolamento & purificação , Fermento Seco , Leveduras/isolamento & purificação
10.
Environ Pollut ; 246: 914-920, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31159141

RESUMO

Pharmaceuticals and analogs of bisphenol A (BPA) are increasingly threatening environmental pollutants. In this study, mixtures of selected pharmaceuticals (diclofenac sodium salt, chloramphenicol, oxytetracycline hydrochloride, fluoxetine hydrochloride, estrone, ketoprofen, progesterone, gemfibrozil and androstenedione) were prepared with BPA and its two analogs (namely, bisphenols F and S) at such ratios to reflect environmentally detectable levels. Then, the mixture solutions were studied with a XenoScreen YES/YAS assay to determine the variations in the initial hormonal response of each pharmaceutical compound due to the presence of a bisphenol analog. The results obtained were modeled with the concentration addition (CA) and independent action (IA) approaches, the trueness of which was studied with model deviation ratios (MDR). The estrogenic agonistic activity of the drugs studied was most strongly affected by the presence of BPA in solution (twenty-one cases of synergy observed for CA models versus twelve cases of antagonism in the case of IA predictions). BPS shows a strong agonistic estrogenic impact on most of the drugs studied at medium and high concentration levels; androgenic agonistic activity was also impaired with elevated concentrations of BPS. Increasing the concentration of BPF in a reaction mixture also increased the number of YES + synergism incidences (for CA modeling). Estrone, progesterone and androstenedione were mostly affected by the highest BPF concentrations studied in the case of androgenic agonistic research performed.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Preparações Farmacêuticas/análise , Fenóis/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Androgênios/análise , Compostos Benzidrílicos/química , Bioensaio , Disruptores Endócrinos/química , Poluentes Ambientais/química , Estrogênios/análise , Fenóis/química , Testes de Toxicidade
11.
BMC Biol ; 17(1): 46, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182083

RESUMO

BACKGROUND: Ribosome biogenesis is a central process in every growing cell. In eukaryotes, it requires more than 250 non-ribosomal assembly factors, most of which are essential. Despite this large repertoire of potential targets, only very few chemical inhibitors of ribosome biogenesis are known so far. Such inhibitors are valuable tools to study this highly dynamic process and elucidate mechanistic details of individual maturation steps. Moreover, ribosome biogenesis is of particular importance for fast proliferating cells, suggesting its inhibition could be a valid strategy for treatment of tumors or infections. RESULTS: We systematically screened ~ 1000 substances for inhibitory effects on ribosome biogenesis using a microscopy-based screen scoring ribosomal subunit export defects. We identified 128 compounds inhibiting maturation of either the small or the large ribosomal subunit or both. Northern blot analysis demonstrates that these inhibitors cause a broad spectrum of different rRNA processing defects. CONCLUSIONS: Our findings show that the individual inhibitors affect a wide range of different maturation steps within the ribosome biogenesis pathway. Our results provide for the first time a comprehensive set of inhibitors to study ribosome biogenesis by chemical inhibition of individual maturation steps and establish the process as promising druggable pathway for chemical intervention.


Assuntos
Ribossomos/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Ribossomos/fisiologia , Saccharomyces cerevisiae/fisiologia
12.
Appl Microbiol Biotechnol ; 103(12): 4869-4880, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31053912

RESUMO

The yeast Saccharomyces cerevisiae has been widely used as a model system for studying the physiological and pharmacological action of small-molecular drugs. Here, a heterozygous diploid S. cerevisiae strain QSS4 was generated to determine whether drugs could induce chromosomal instability by determining the frequency of mitotic recombination. Using the combination of a custom SNP microarray and yeast screening system, the patterns of chromosomal instability induced by drugs were explored at the whole genome level in QSS4. We found that Zeocin (a member of the bleomycin family) treatment increased the rate of genomic alterations, including aneuploidy, loss of heterozygosity (LOH), and chromosomal rearrangement over a hundred-fold. Most recombination events are likely to be initiated by DNA double-stand breaks directly generated by Zeocin. Another remarkable finding is that G4-motifs and low GC regions were significantly underrepresented within the gene conversion tracts of Zeocin-induced LOH events, indicating that certain DNA regions are less preferred Zeocin-binding sites in vivo. This study provides a novel paradigm for evaluating genetic toxicity of small-molecular drugs using yeast models.


Assuntos
Instabilidade Cromossômica/efeitos dos fármacos , Cromossomos Fúngicos , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Aneuploidia , Bleomicina/farmacologia , Divisão Celular , Rearranjo Gênico , Instabilidade Genômica , Perda de Heterozigosidade , Recombinação Genética
13.
Molecules ; 24(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067673

RESUMO

Flor velum yeast growth activators during biological aging are currently unknown. In this sense, this research focuses on the use of bee pollen as a flor velum activator. Bee pollen influence on viable yeast development, surface hydrophobicity, and yeast assimilable nitrogen has already been studied. Additionally, bee pollen effects on the main compounds related to flor yeast metabolism and wine sensory characteristics have been evaluated. "Fino" (Sherry) wine was supplemented with bee pollen using six different doses ranging from 0.1 to 20 g/L. Its addition in a dose equal or greater than 0.25 g/L can be an effective flor velum activator, increasing yeast populations and its buoyancy due to its content of yeast assimilable nitrogen and fatty acids. Except for the 20 g/L dose, pollen did not induce any significant effect on flor velum metabolism, physicochemical parameters, organic acids, major volatile compounds, or glycerol. Sensory analysis showed that low bee pollen doses increase wine's biological aging attributes, obtaining the highest score from the tasting panel. Multiflora bee pollen could be a natural oenological tool to enhance flor velum development and wine sensory qualities. This study confirms association between the bee pollen dose applied and the flor velum growth rate. The addition of bee pollen could help winemakers to accelerate or reimplant flor velum in biologically aged wines.


Assuntos
Abelhas/química , Pólen/química , Saccharomyces cerevisiae/crescimento & desenvolvimento , Vinho/microbiologia , Animais , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Fermentação , Nitrogênio/química , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo
14.
Environ Toxicol ; 34(9): 992-1000, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31087746

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) comprise a large family of toxic compounds that come from natural and anthropogenic sources. Chrysene is a PAH with multiple effects, but the toxic potentials of mono-methylchrysenes are less characterized. A comparison of chrysene and six mono-methylchrysenes was performed using assays for cytotoxicity, human aryl hydrocarbon receptor (AhR) reporter gene signaling, and AhR-regulated target gene and protein expression. Sulforhodamine B and trypan blue dye binding assays revealed these chrysenes to be similar in their cytotoxic effects on HepG2 cells. A yeast-based reporter assay detecting human AhR-mediated gene expression identified 4-methylchrysene as being six times more potent and 5-methylchrysene about one-third as potent as chrysene. Other methylchrysenes were more similar to chrysene in the ability to act as AhR ligands. The mono-methylchrysenes all strongly induced CYP1A1 mRNA and protein and moderately induced CYP1B1 expression in HepG2 cells. Levels of CYP1A2 mRNA were induced at higher concentrations of the chrysenes, but protein expression was not significantly altered. The PCR-based gene expression and immunoblotting analyses indicated induced expression differences across the chrysene members were similar to each other. Overall, the effects of methylated chrysenes were comparable to unsubstituted chrysene, suggesting members of this group may be considered approximately equivalent in their effects. © 2019 Wiley Periodicals, Inc.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Crisenos/toxicidade , Expressão Gênica/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1B1/genética , Genes Reporter/efeitos dos fármacos , Células Hep G2 , Humanos , Receptores de Hidrocarboneto Arílico/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Transdução de Sinais/efeitos dos fármacos
15.
Molecules ; 24(8)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010227

RESUMO

Endocrine active compounds with structural similarities to natural hormones such as 17ß-estradiol (E2) and androgen are suspected to affect the human endocrine system by inducing hormone-dependent effects. This study aimed to detect the (anti-)estrogenic and (anti-)androgenic activities of mono-(2-ethylhexyl) phthalate (MEHP) by yeast estrogen/androgen bioassay (YES/YAS). In addition, the mechanism and uptake of MEHP to receptors during agonistic and antagonistic activities were investigated through the activation signal recovery test and chromatographic analysis using liquid chromatography and tandem mass spectrometry (LC-MS/MS). Estrogenic and androgenic activities of MEHP were not observed. However, MEHP exhibited anti-estrogenic (IC50 = 125 µM) and anti-androgenic effects (IC50 = 736 µM). It was confirmed that these inhibitory effects of MEHP were caused by receptor-mediated activity of the estrogen receptor and non-receptor-mediated activity of the androgen receptor in an activation signal recovery test. When IC50 concentrations of anti-estrogenic and androgenic activity of MEHP were exposed to yeast cells, the uptake concentration observed was 0.0562 ± 0.0252 µM and 0.143 ± 0.0486 µM by LC-MS/MS analysis.


Assuntos
Bioensaio/métodos , Dietilexilftalato/análogos & derivados , Disruptores Endócrinos/farmacologia , Receptores Androgênicos/metabolismo , Receptores Estrogênicos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Intervalos de Confiança , Dietilexilftalato/farmacologia , Feminino , Humanos , Receptores Androgênicos/genética , Receptores Estrogênicos/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Espectrometria de Massas em Tandem
16.
Molecules ; 24(7)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30978970

RESUMO

The aim of this study was to investigate anti-aging molecules from Onosma bracteatum Wall, a traditional medicinal plant used in the Unani and Ayurvedic systems of medicine. During bioassay-guided isolation, two known benzoquinones, allomicrophyllone (1) and ehretiquinone (2) along with three novel benzoquinones designated as ehretiquinones B-D (3-5) were isolated from O. bracteatum. Their structures were characterized by spectroscopic analysis through 1D and 2D NMR, by MS spectroscopic analysis and comparing with those reported in the literatures. The anti-aging potential of the isolated benzoquinones was evaluated through a yeast lifespan assay, and the results indicated that 1, 2, 4 and 5 significantly extended the replicative lifespan of K6001 yeast, indicating that these benzoquinones obtained from O. brateatum have the ability to be employed as a potential therapeutic agent against age-related diseases.


Assuntos
Envelhecimento/efeitos dos fármacos , Benzoquinonas/química , Boraginaceae/química , Longevidade/efeitos dos fármacos , Envelhecimento/fisiologia , Benzoquinonas/isolamento & purificação , Humanos , Medicina Ayurvédica , Estrutura Molecular , Plantas Medicinais/química , Saccharomyces cerevisiae/efeitos dos fármacos
17.
Food Microbiol ; 82: 20-29, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027774

RESUMO

This study evaluated the efficacy of the essential oil from Mentha piperita L. (MPEO) to inactivate cells of the potentially spoilage yeasts Candida albicans, Candida tropicalis, Pichia anomala and Saccharomyces cerevisiae in cashew, guava, mango and pineapple juices during 72 h of refrigerated storage. Damage in different physiological functions caused by MPEO in S. cerevisiae in cashew and guava juices were investigated using flow cytometry (FC). The effects of the incorporation of an effective anti-yeast MPEO dose on sensory characteristics of juices were also evaluated. MPEO displayed minimum inhibitory concentration of 1.875 µL/mL against all tested yeasts. A >5 log reduction in counts of C. albicans, P. anomala and S. cerevisiae was observed in cashew and guava juices with 7.5 and 3.75 µL/mL MPEO. Tested MPEO concentrations (1.875, 3.75 and 7.5 µL/mL) were not effective to cause >5 log reduction in counts of target yeasts in mango and pineapple juices during 72 h of exposure. Incorporation of 1.875 µL/mL MPEO in cashew and guava juices strongly compromised membrane permeability, membrane potential, enzymatic activity and efflux pump activity in S. cerevisiae cells. This same MPEO concentration did not affect appearance, odor and viscosity in fruit juices, but negatively affected their taste and aftertaste. These results show the efficacy of MPEO to inactivate potentially spoilage yeasts in fruit juices through disturbance of different physiological functions in yeast cells. However, the combined use of MPEO with other technologies should be necessary to decrease its effective anti-yeast dose in fruit juices and, consequently, the possible negative impacts on specific sensory properties of these products.


Assuntos
Contaminação de Alimentos/prevenção & controle , Sucos de Frutas e Vegetais/microbiologia , Mentha piperita/química , Óleos Vegetais/farmacologia , Leveduras/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Pichia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Leveduras/fisiologia
18.
Int J Food Microbiol ; 300: 43-52, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31035250

RESUMO

The spoilage of foods caused by the growth of undesirable yeast species is a problem in the food industry. Yeast species such as Zygosaccharomyces bailii, Zygosaccharomyces rouxii, Debaryomyces hansenii, Kluyveromyces lactis and Saccharomyces cerevisiae have been encountered in foods such as high sugar products, fruit juices, wine, mayonnaise, chocolate and soft drinks. The demand for new methods of preservations has increased because of the negative association attached to chemical preservatives. The sequence of a novel short peptide (KKFFRAWWAPRFLK-NH2) was modified to generate three versions of this original peptide. These peptides were tested for the inhibition of the yeasts mentioned above, allowing for the better understanding of their residue modifications. The range of the minimum inhibitory concentration was between 25 and 200 µg/mL. Zygosaccharomyces bailii was the most sensitive strain to the peptides, while Zygosaccharomyces rouxii was the most resistant. Membrane permeabilisation was found to be responsible for yeast inhibition at a level which was a two-fold increase of the MIC (400 µg/mL). The possibility of the production of reactive oxygen species was also assessed but was not recognised as a factor involved for the peptides' mode of action. Their stability in different environments was also tested, focusing on high salt, pH and thermal stability. The newly designed peptides showed good antifungal activity against some common food spoilage yeasts and has been proven effective in the application in Fanta Orange. These efficient novel peptides represent a new source of food preservation that can be used as an alternative for current controversial preservatives used in the food industry.


Assuntos
Microbiologia de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Peptídeos/farmacologia , Leveduras/efeitos dos fármacos , Antifúngicos/farmacologia , Indústria de Processamento de Alimentos , Sucos de Frutas e Vegetais/microbiologia , Kluyveromyces/efeitos dos fármacos , Kluyveromyces/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Leveduras/crescimento & desenvolvimento , Zygosaccharomyces/crescimento & desenvolvimento
19.
Bioelectrochemistry ; 128: 148-154, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31003053

RESUMO

Antifungal substances that are used for the treatment of candidiasis have considerable side effects and Candida yeasts are known to obtain drug resistance. The multidrug resistance cases are promoting the search for the new alternative methods and pulsed electric field (PEF) treatment could be the alternative or could be used in combination with conventional therapy for the enhancement of the effect. We have shown that nanosecond range PEF is capable to induce apoptosis in the S. cerevisiae as well as in the drug resistant C. lusitaniae and C. guilliermondii. Supplementing the PEF procedure with formic acid (final concentration 0.05%) resulted in improvement of the inactivation efficacy and the induction of apoptosis in the majority of the yeast population. After the treatment yeast were displaying the DNA strand brakes, activation of yeast metacaspase and externalization of phosphatidylserine. Apoptotic phenotypes were registered already after 30 kV/cm × 250 ns × 50 pulses treatment. The highest number of apoptotic yeast cells (>60%) was obtained during the 30 kV/cm × 750 ns × 50 pulses protocol when combined with 0.05% formic acid. The results of our study are useful for development of new non-toxic and effective protocols to induce programed cell death in different yeast species and thus minimize inflammation of the tissue.


Assuntos
Apoptose/efeitos dos fármacos , Candida/efeitos dos fármacos , Caspases/metabolismo , Eletroporação/métodos , Formiatos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Candida/classificação , Candida/citologia , Candida/enzimologia , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/enzimologia , Especificidade da Espécie
20.
Chemosphere ; 228: 219-231, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029968

RESUMO

Integration of chemical-genetic interaction data with biological functions provides a mechanistic understanding of how toxic compounds affect cells. Mono-(2-ethylhexyl)-phthalate (MEHP) is an active metabolite of di-(2-ethylhexyl)-phthalate (DEHP), a commonly used plasticizer. MEHP adversely affects human health causing hepatotoxicity and reproductive toxicity. How MEHP affects cellular physiology is not fully understood. We utilized a genome-wide competitive fitness-based assay called 'chemogenomic profiling' to determine the genetic interaction map of MEHP in Saccharomyces cerevisiae. Gene Ontology enrichment analysis of 218 genes that provide resistance to MEHP indicated that MEHP affects seven cellular processes namely: (1) cellular amino acid biosynthetic process, (2) sterol biosynthetic process, (3) cellular transport, (4) transcriptional and translational regulation, (5) protein glycosylation, (6) cytokinesis and cell morphogenesis and (7) ionic homeostasis. We show that MEHP protects yeast cells from membrane perturbing agents such as amphotericin B, dihydrosphingosine and phytosphingosine. Moreover, we also demonstrate that MEHP compromises the integrity of the yeast plasma membrane and cell wall. Our work provides a basis for further investigation of MEHP toxicity in humans.


Assuntos
Ácidos Ftálicos/toxicidade , Plastificantes/toxicidade , Vias Biossintéticas/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Dietilexilftalato/metabolismo , Humanos , Ácidos Ftálicos/farmacologia , Plastificantes/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo
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