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1.
Heliyon ; 9(3): e13797, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36811015

RESUMO

The majority of research to combat SARS-CoV-2 infection exploits the adaptive immune system, but innate immunity, the first line of defense against pathogenic microbes, is equally important in understanding and controlling infectious diseases. Various cellular mechanisms provide physiochemical barriers to microbe infection in mucosal membranes and epithelia, with extracellular polysaccharides, particularly sulfated polysaccharides, being among the most widespread and potent extracellular and secreted molecules blocking and deactivating bacteria, fungi, and viruses. New research reveals that a range of polysaccharides effectively inhibits COV-2 infection of mammalian cells in culture. This review provides an overview of sulfated polysaccharides nomenclature, its significance as immunomodulators, antioxidants, antitumors, anticoagulants, antibacterial, and as potent antivirals. It summarizes current research on various interactions of sulfated polysaccharide with a range of viruses, including SARS-CoV-2, and their application for potential treatments for COVID-19. These molecules interact with biochemical signaling in immune cell responses, by actions in oxidative reactions, cytokine signaling, receptor binding, and through antiviral and antibacterial toxicity. These properties provide the potential for the development of novel therapeutic treatments for SARS-CoV-2 and other infectious diseases from modified polysaccharides.

2.
Gels ; 9(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36661799

RESUMO

Ivory nut seeds have been traditionally exploited in Central and South America for obtaining vegetable ivory. The residues from this industry are susceptible to valorization as a source of fatty acids (by organic extraction) and mannans (by alkaline dissolution and regeneration). Nonetheless, cellulose may also be recovered at the end of this fractionation process by acid hydrolysis and functionalization, with associated advantages over other lignocellulosic sources due to the absence of lignin in the endospermic tissue. In this work, various experimental parameters (sulfuric acid concentration, temperature, and hydrolysis time) were investigated to optimize the processing conditions for preparing stable nanocellulose suspensions after ultrasonication. The most stable nanocellulose gel (1 wt% solid content) was obtained after 4-h hydrolysis at 60 °C with 8 M H2SO4 and was characterized by using complementary tech-niques, including dynamic light scattering (DLS), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), nano-fibril sulfation measurements, vibrational and solid-state nuclear magnetic resonance (CP/MAS 13C-NMR) spectroscopies, and thermal analysis. This nanocellulose hydrogel is susceptible to further utilization in various applications and fields, e.g., in agricul-ture for controlling the release of agrochemicals, in pharmaceutics for developing new dosage forms, and in the treatment of wastewater from the textile and paper industries.

3.
Environ Sci Pollut Res Int ; 26(27): 28162-28172, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31363969

RESUMO

Pollution caused by heavy metals is a prime concern due to its impact on human health, animals, and ecosystems. Cr(VI), generated in a range of different industries as a liquid effluent, is one of the most frequent contaminants. In the work presented herein, the adsorption efficiency of three species of native yeasts from Ecuador (Kazachstania yasuniensis, Kodamaea transpacifica, and Saturnispora quitensis) for Cr(VI) removal from simulated wastewater was assessed, taking Saccharomyces cerevisiae as a reference. After disruption of the flocs of yeast with a cationic surfactant, adsorption capacity, kinetics, and biosorption isotherms were studied. K. transpacifica isolate was found to feature the highest efficiency among the four yeasts tested, as a result of its advantageous combination of surface charge, individual cell size (4.04 µm), and surface area (1588.27 m2/L). The performance of S. quitensis was only slightly lower. The remarkable biosorption capacities of these two isolates (476.19 and 416.67 mg of Cr(VI)/g of yeast, respectively) evidence the potential of non-conventional yeast species as sorption microbial particles for polluted water remediation.


Assuntos
Cromo/química , Metais Pesados/análise , Saccharomyces cerevisiae/metabolismo , Tensoativos/química , Adsorção , Ecossistema , Equador , Cinética , Metais Pesados/química , Saccharomyces cerevisiae/química , Águas Residuárias , Poluição da Água
4.
Braz. J. Microbiol. ; 49(4): 808-815, Oct.-Dec. 2018. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-738184

RESUMO

Chicha, a type of beer made mainly with maize or cassava, is a traditional fermented beverage of the Andean region. There have only been a few studies on yeasts associated with chicha fermentation, and the species diversity occurring during the production of this beverage is not known. The objective of this study was to determine the biodiversity of yeasts in chicha, and to characterize the Saccharomyces cerevisiae populations associated with the production of chicha de jora, seven-grain chicha, chicha de yuca, and chicha de morocho in Ecuador. The molecular diversity of S. cerevisiae populations was determined by restriction polymorphism mitochondrial profiles. The beverages were characterized based on their physicochemical parameters. Twenty-six species were identified, and the most prevalent species were S. cerevisiae and Torulaspora delbrueckii. Other yeast species were isolated at low frequencies. Among 121 isolates of S. cerevisiae, 68 different mtDNA molecular profiles were identified. These results showed that chichas are fermented by a high number of different strains of S. cerevisiae. Some other species provided a minor contribution to the fermentation process. The chicha presented generally similar physicochemical parameters to those observed for other traditional fermented beverages, and can be considered as an acid fermented beverage.(AU)

5.
Braz. j. microbiol ; Braz. j. microbiol;49(4): 808-815, Oct.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974288

RESUMO

ABSTRACT Chicha, a type of beer made mainly with maize or cassava, is a traditional fermented beverage of the Andean region. There have only been a few studies on yeasts associated with chicha fermentation, and the species diversity occurring during the production of this beverage is not known. The objective of this study was to determine the biodiversity of yeasts in chicha, and to characterize the Saccharomyces cerevisiae populations associated with the production of chicha de jora, seven-grain chicha, chicha de yuca, and chicha de morocho in Ecuador. The molecular diversity of S. cerevisiae populations was determined by restriction polymorphism mitochondrial profiles. The beverages were characterized based on their physicochemical parameters. Twenty-six species were identified, and the most prevalent species were S. cerevisiae and Torulaspora delbrueckii. Other yeast species were isolated at low frequencies. Among 121 isolates of S. cerevisiae, 68 different mtDNA molecular profiles were identified. These results showed that chichas are fermented by a high number of different strains of S. cerevisiae. Some other species provided a minor contribution to the fermentation process. The chicha presented generally similar physicochemical parameters to those observed for other traditional fermented beverages, and can be considered as an acid fermented beverage.


Assuntos
Saccharomyces cerevisiae/isolamento & purificação , Cerveja/microbiologia , Leveduras/isolamento & purificação , Leveduras/metabolismo , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Cerveja/análise , Leveduras/classificação , Leveduras/genética , Manihot/metabolismo , Manihot/microbiologia , Zea mays/metabolismo , Zea mays/microbiologia , Biodiversidade , Equador , Fermentação
6.
Braz J Microbiol ; 49(4): 808-815, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29705164

RESUMO

Chicha, a type of beer made mainly with maize or cassava, is a traditional fermented beverage of the Andean region. There have only been a few studies on yeasts associated with chicha fermentation, and the species diversity occurring during the production of this beverage is not known. The objective of this study was to determine the biodiversity of yeasts in chicha, and to characterize the Saccharomyces cerevisiae populations associated with the production of chicha de jora, seven-grain chicha, chicha de yuca, and chicha de morocho in Ecuador. The molecular diversity of S. cerevisiae populations was determined by restriction polymorphism mitochondrial profiles. The beverages were characterized based on their physicochemical parameters. Twenty-six species were identified, and the most prevalent species were S. cerevisiae and Torulaspora delbrueckii. Other yeast species were isolated at low frequencies. Among 121 isolates of S. cerevisiae, 68 different mtDNA molecular profiles were identified. These results showed that chichas are fermented by a high number of different strains of S. cerevisiae. Some other species provided a minor contribution to the fermentation process. The chicha presented generally similar physicochemical parameters to those observed for other traditional fermented beverages, and can be considered as an acid fermented beverage.


Assuntos
Cerveja/microbiologia , Saccharomyces cerevisiae/isolamento & purificação , Leveduras/isolamento & purificação , Leveduras/metabolismo , Cerveja/análise , Biodiversidade , Equador , Fermentação , Manihot/metabolismo , Manihot/microbiologia , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Leveduras/classificação , Leveduras/genética , Zea mays/metabolismo , Zea mays/microbiologia
7.
Int J Syst Evol Microbiol ; 65(Pt 4): 1304-1309, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25644482

RESUMO

Seven strains representing a novel yeast species belonging to the genus Kazachstania were found at several collection sites on both mainland Ecuador (Yasuní National Park) and the Galápagos (Santa Cruz Island). Two strains (CLQCA 20-132(T) and CLQCA 24SC-045) were isolated from rotten wood samples, two further strains (CLQCA 20-280 and CLQCA 20-348) were isolated from soil samples, and three strains (CLQCA 20-198, CLQCA 20-374 and CLQCA 20-431) were isolated from decaying fruits. Sequence analyses of the D1/D2 domains of the LSU rRNA gene and ribosomal internal transcribed spacer (ITS) region indicated that the novel species is most closely related to Kazachstania servazzii and Kazachstania unispora. Although the strains could not be distinguished from one another based upon their differing geographical origins, they could be differentiated according to their isolation source (fruit, soil or wood) by ITS sequencing. The species name Kazachstania yasuniensis sp. nov. is proposed to accommodate these strains, with CLQCA 20-132(T) ( = CBS 13946(T) = NCYC 4008(T)) designated the type strain.


Assuntos
Frutas/microbiologia , Filogenia , Saccharomycetales/classificação , Microbiologia do Solo , Madeira/microbiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Equador , Ilhas , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , RNA Ribossômico/genética , Saccharomycetales/genética , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA
8.
Int J Syst Evol Microbiol ; 63(Pt 1): 393-397, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23104360

RESUMO

In the course of an on-going study aimed at cataloguing the natural yeast biodiversity found in Ecuador, two strains (CLQCA 13-025 and CLQCA 20-004(T)) were isolated from samples of cow manure and rotten wood collected in two separate provinces of the country (Orellana and Bolívar). These strains were found to represent a novel yeast species based on the sequences of their D1/D2 domain of the large-subunit (LSU) rRNA gene and their physiological characteristics. Phylogenetic analysis based on LSU D1/D2 sequences revealed this novel species to belong to the Metschnikowia clade and to be most closely related to Candida suratensis, a species recently discovered in a mangrove forest in Thailand. The species name of Candida ecuadorensis sp. nov. is proposed to accommodate these strains, with strain CLQCA 20-004(T) (=CBS 12653(T) = NCYC 3782(T)) designated as the type strain.


Assuntos
Candida/classificação , Esterco/microbiologia , Filogenia , Madeira/microbiologia , Animais , Biodiversidade , Candida/genética , Candida/isolamento & purificação , Bovinos , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Equador , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Análise de Sequência de DNA
9.
Int J Food Microbiol ; 153(1-2): 10-4, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22088606

RESUMO

Four strains representing a novel yeast species belonging to the genus Candida were independently isolated in Taiwan and Ecuador. Two strains (G17(T) and G31) were isolated in Taiwan, by pellet precipitation from plastic-bottled tea drinks produced in Indonesia, while two additional strains (CLQCA 10-049 and CLQCA 10-062) were recovered from ancient chicha fermentation vessels found in tombs in Quito, Ecuador. These four strains were morphologically, and phylogenetically identical to each other. No sexual reproduction was observed on common sporulation media. Large-subunit (LSU) rRNA gene sequence analysis revealed the four strains to belong to the Lodderomyces clade, closely related to members of the Candida parapsilosis species complex. The four strains, which have identical LSU D1/D2 sequences, differ from their closest phylogenetic neighbors, Candida orthopsilosis and Candida parapsilosis, by 6-9 nt substitutions, respectively. Physiologically, the four strains are similar to Candida parapsilosis, although they can be distinguished from their closest relative by the assimilation of arbutin, nitrite, and creatine. The Indonesian and Ecuadorian strain sets can also be distinguished from one another based on ITS sequencing, differing by 4 substitutions in ITS1 and 1 single nucleotide indel in ITS2. Collectively, the results indicate that the four strains represent a previously unrecognized species of Candida. The name Candida theae sp. nov. is proposed to accommodate these strains, with G-17(T) (BCRC 23242(T)=CBS 12239(T)=ATCC MYA-4746(T)) designated as the type strain.


Assuntos
Bebidas/microbiologia , Candida/classificação , Candida/isolamento & purificação , Animais , Sequência de Bases , Cerveja/microbiologia , Candida/genética , Precipitação Química , DNA Fúngico/genética , Equador , Fermentação , Microbiologia de Alimentos , Genes de RNAr , Indonésia , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , RNA Ribossômico/genética , Análise de Sequência de DNA , Taiwan , Chá/microbiologia
10.
Int J Syst Evol Microbiol ; 61(Pt 12): 3072-3076, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21335499

RESUMO

A single strain, CLQCA-10-114(T), representing a novel yeast species belonging to the genus Saturnispora was isolated from the fruit of an unidentified species of bramble (Rubus sp.), collected from the Maquipucuna cloud forest reserve, near Quito, in Ecuador. Sequence analyses of the D1/D2 domains of the large-subunit rRNA gene and ribosomal internal transcribed spacer region indicated that the novel species is most closely related to the recently described species Saturnispora gosingensis, isolated from the fruiting body of a mushroom collected in Taiwan, and Saturnispora hagleri, a Drosophila-associated yeast found in Brazil. The name Saturnispora quitensis sp. nov. is proposed to accommodate this strain; the type strain is CLQCA-10-114(T) (=CBS 12184(T)=NCYC 3744(T)).


Assuntos
Rosaceae/microbiologia , Saccharomycetales/classificação , Saccharomycetales/isolamento & purificação , Conservação dos Recursos Naturais , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Equador , Frutas/microbiologia , Dados de Sequência Molecular , Filogenia , Saccharomycetales/genética
11.
FEMS Yeast Res ; 9(5): 784-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19459983

RESUMO

In the course of a yeast biodiversity survey of different ecological habitats found in Ecuador, two yeast strains (CLQCA 20-011(T) and CLQCA20-014) were isolated from samples of rotten wood and fallen leaf debris collected at separate sites in the central region of the Ecuadorian Amazonia. These strains were found to represent a novel yeast species based on the sequences of their D1/D2 domain of the large-subunit (LSU) rRNA gene and their physiological characteristics. Phylogenetic analysis based on LSU D1/D2 sequences revealed this novel species to be most closely related to Candida asparagi, Candida fructus, Candida musae and two as yet undescribed Candida species, with the six yeast taxa collectively forming a distinct species group within the Clavispora clade. The species name of Candida carvajalis sp. nov. is proposed to accommodate these strains, with CLQCA 20-011(T) (NCYC 3509(T), CBS 11361(T)) designated as the type strain.


Assuntos
Candida/classificação , Candida/isolamento & purificação , Folhas de Planta/microbiologia , Madeira/microbiologia , Candida/genética , Candida/metabolismo , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Equador , Genes de RNAr , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Filogenia , RNA Fúngico/genética , RNA Ribossômico/genética , Análise de Sequência de DNA , Árvores
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