Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 526.590
Filtrar
1.
Microb Cell Fact ; 21(1): 5, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983541

RESUMO

BACKGROUND: The filamentous fungus Trichoderma reesei is a widely used workhorse for cellulase production in industry due to its prominent secretion capacity of extracellular cellulolytic enzymes. However, some key components are not always sufficient in this cellulase cocktail, making the conversion of cellulose-based biomass costly on the industrial scale. Development of strong and efficient promoters would enable cellulase cocktail to be optimized for bioconversion of biomass. RESULTS: In this study, a synthetic hybrid promoter was constructed and applied to optimize the cellulolytic system of T. reesei for efficient saccharification towards corncob residues. Firstly, a series of 5' truncated promoters in different lengths were established based on the strong constitutive promoter Pcdna1. The strongest promoter amongst them was Pcdna1-3 (- 640 to - 1 bp upstream of the translation initiation codon ATG), exhibiting a 1.4-fold higher activity than that of the native cdna1 promoter. Meanwhile, the activation region (- 821 to - 622 bp upstream of the translation initiation codon ATG and devoid of the Cre1-binding sites) of the strong inducible promoter Pcbh1 was cloned and identified to be an amplifier in initiating gene expression. Finally, this activation region was fused to the strongest promoter Pcdna1-3, generating the novel synthetic hybrid promoter Pcc. This engineered promoter Pcc drove strong gene expression by displaying 1.6- and 1.8-fold stronger fluorescence intensity than Pcbh1 and Pcdna1 under the inducible condition using egfp as the reporter gene, respectively. Furthermore, Pcc was applied to overexpress the Aspergillus niger ß-glucosidase BGLA coding gene bglA and the native endoglucanase EG2 coding gene eg2, achieving 43.5-fold BGL activity and 1.2-fold EG activity increase, respectively. Ultimately, to overcome the defects of the native cellulase system in T. reesei, the bglA and eg2 were co-overexpressed under the control of Pcc promoter. The bglA-eg2 double expression strain QPEB70 exhibited a 178% increase in total cellulase activity, whose cellulase system displayed 2.3- and 2.4-fold higher saccharification efficiency towards acid-pretreated and delignified corncob residues than the parental strain, respectively. CONCLUSIONS: The synthetic hybrid promoter Pcc was generated and employed to improve the cellulase system of T. reesei by expressing specific components. Therefore, construction of synthetic hybrid promoters would allow particular cellulase genes to be expressed at desired levels, which is a viable strategy to optimize the cellulolytic enzyme system for efficient biomass bioconversion.


Assuntos
Celulase/genética , Celulase/metabolismo , Hypocreales/genética , Hypocreales/metabolismo , Regiões Promotoras Genéticas , Zea mays/metabolismo , Biomassa , Celulose/metabolismo , Proteínas Fúngicas/genética , Zea mays/microbiologia
2.
Invest Ophthalmol Vis Sci ; 63(1): 5, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34985498

RESUMO

Purpose: The gut microbiome has been linked to disease pathogenesis through their interaction in metabolic, endocrine, and immune functions. The goal of this study was to determine whether the gut and plasma microbiota could transfer microbes to the retina in type 1 diabetic mice with retinopathy. Methods: We analyzed the fecal, plasma, whole globe, and retina microbiome in Akita mice and compared with age-matched wild-type (WT) mice using 16S rRNA sequencing and metatranscriptomic analysis. To eliminate the contribution of the ocular surface and plasma microbiome, mice were perfused with sterile saline solution, the whole globes were extracted, and the neural retina was removed under sterile conditions for retinal microbiome. Results: Our microbiome analysis revealed that Akita mice demonstrated a distinct pattern of microbes within each source: feces, plasma, whole globes, and retina. WT mice and Akita mice experienced transient bacteremia in the plasma and retina. Bacteria were identified in the retina of the Akita mice, specifically Corynebacterium, Pseudomonas, Lactobacillus, Staphylococcus, Enterococcus, and Bacillus. Significantly increased levels of peptidoglycan (0.036 ± 0.001 vs. 0.023 ± 0.002; P < 0.002) and TLR2 (3.47 ± 0.15 vs. 1.99 ± 0.07; P < 0.0001) were observed in the retina of Akita mice compared to WT. Increased IBA+ cells in the retina, reduced a- and b-waves on electroretinography, and increased acellular capillary formation demonstrated the presence of retinopathy in the Akita cohort compared to WT mice. Conclusions: Together, our findings suggest that transient bacteremia exists in the plasma and retina of both cohorts. The bacteria found in Akita mice are distinct from WT mice and may contribute to development of retinal inflammation and barrier dysfunction in retinopathy.


Assuntos
Bacteriemia/microbiologia , Bactérias/isolamento & purificação , Retinopatia Diabética/microbiologia , Fezes/microbiologia , Retina/microbiologia , Animais , Bactérias/genética , Diabetes Mellitus Tipo 1/microbiologia , Modelos Animais de Doenças , Eletrorretinografia , Ensaio de Imunoadsorção Enzimática , Olho/microbiologia , Microbioma Gastrointestinal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microbiota/fisiologia , RNA Ribossômico 16S/genética
4.
BMC Plant Biol ; 22(1): 7, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979915

RESUMO

BACKGROUND: Plant immunity against pathogens and pests is comprised of complex mechanisms orchestrated by signaling pathways regulated by plant hormones [Salicylic acid (SA) and Jasmonic acid (JA)]. Investigations of plant immune response to phytopathogens and phloem-feeders have revealed that SA plays a critical role in reprogramming of the activity and/or localization of transcriptional regulators via post-translational modifications. We explored the contributing effects of herbivory by a phytopathogen vector [Asian citrus psyllid, Diaphorina citri] and pathogen [Candidatus Liberibacter asiaticus (CaLas)] infection on response of sweet orange [Citrus sinensis (L.) Osbeck] using manipulative treatments designed to mimic the types of infestations/infections that citrus growers experience when cultivating citrus in the face of Huanglongbing (HLB) disease. RESULTS: A one-time (7 days) inoculation access period with CaLas-infected vectors caused SA-associated upregulation of PR-1, stimulating defense response after a long period of infection without herbivory (270 and 360 days). In contrast, while repeated (monthly) 'pulses' of 7 day feeding injury by psyllids stimulated immunity in CaLas-infected citrus by increasing SA in leaves initially (up to 120 days), long-term (270 and 360 days) repeated herbivory caused SA to decrease coincident with upregulation of genes associated with SA metabolism (BMST and DMR6). Similarly, transcriptional responses and metabolite (SA and its analytes) accumulation in citrus leaves exposed to a continuously reproducing population of D. citri exhibited a transitory upregulation of genes associated with SA signaling at 120 days and a posterior downregulation after long-term psyllid (adults and nymphs) feeding (270 and 360 days). CONCLUSIONS: Herbivory played an important role in regulation of SA accumulation in mature leaves of C. sinensis, whether or not those trees were coincidentally infected with CaLas. Our results indicate that prevention of feeding injury inflicted by D. citri from the tritrophic interaction may allow citrus plants to better cope with the consequences of CaLas infection, highlighting the importance of vector suppression as a component of managing this cosmopolitan disease.


Assuntos
Citrus sinensis/imunologia , Herbivoria , Interações Hospedeiro-Patógeno , Reguladores de Crescimento de Plantas/metabolismo , Imunidade Vegetal , Ácido Salicílico/metabolismo , Animais , Citrus sinensis/microbiologia , Hemípteros/fisiologia , Liberibacter/fisiologia , Doenças das Plantas/microbiologia
5.
BMC Plant Biol ; 22(1): 3, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979923

RESUMO

BACKGROUND: Fusarium head blight (FHB) caused by Fusarium graminearum is a devastating fungal disease of wheat. The mechanism underlying F. graminearum-wheat interaction remains largely unknown. tRNA-derived fragments (tRFs) are RNase-dependent small RNAs derived from tRNAs, and they have not been reported in wheat yet, and whether tRFs are involved in wheat-F. graminearum interactions remains unknown. RESULTS: Herein, small RNAs from the spikelets inoculated with F. graminearum and mock from an FHB-susceptible variety Chinese Spring (CS) and an FHB-resistant variety Sumai3 (SM) were sequenced respectively. A total of 1249 putative tRFs were identified, in which 15 tRFs was CS-specific and 12 SM-specific. Compared with mock inoculation, 39 tRFs were significantly up-regulated across both wheat varieties after F. graminearum challenge and only nine tRFs were significantly down-regulated. tRFGlu, tRFLys and tRFThr were dramatically induced by F. graminearum infection, with significantly higher fold changes in CS than those in SM. The expression patterns of the three highly induced tRFs were further validated by stem-loop qRT-PCR. The accumulation of tRFs were closely related to ribonucleases T2 family members, which were induced by F. graminearum challenge. The tRFs' targets in host were predicted and were validated by RNA sequencing. CONCLUSION: Integrative analysis of the differentially expressed tRFs and their candidate targets indicated that tRFGlu, tRFLys and tRFThr might negatively regulate wheat resistance to FHB. Our results unvealed the potential roles of tRFs in wheat-F. graminearum interactions.


Assuntos
Fusarium/fisiologia , Doenças das Plantas/genética , RNA de Plantas/genética , RNA de Transferência/genética , Triticum/genética , Suscetibilidade a Doenças/microbiologia , Doenças das Plantas/microbiologia , RNA de Plantas/metabolismo , RNA de Transferência/metabolismo , Triticum/metabolismo , Triticum/microbiologia
6.
BMC Plant Biol ; 22(1): 12, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979929

RESUMO

BACKGROUND: Taxol from Taxus species is a precious drug used for the treatment of cancer and can effectively inhibit the proliferation of cancer cells. However, the growth of Taxus plants is very slow and the content of taxol is quite low. Therefore, it is of great significance to improve the yield of taxol by modern biotechnology without destroying the wild forest resources. Endophytic fungus which symbiosis with their host plants can promote the growth and secondary metabolism of medicinal plants. RESULTS: Here, an endophytic fungus KL27 was isolated from T. chinensis, and identified as Pseudodidymocyrtis lobariellae. The fermentation broth of KL27 (KL27-FB) could significantly promote the accumulation of taxol in needles of T. chinensis, reaching 0.361 ± 0.082 mg/g·DW (dry weight) at 7 days after KL27-FB treatment, which is 3.26-fold increase as compared to the control. The RNA-seq and qRT-PCR showed that KL27-FB could significantly increase the expression of key genes involved in the upstream pathway of terpene synthesis (such as DXS and DXR) and those in the taxol biosynthesis pathway (such as GGPPS, TS, T5OH, TAT, T10OH, T14OH, T2OH, TBT, DBAT and PAM), especially at the early stage of the stimulation. Moreover, the activation of jasmonic acid (JA) biosynthesis and JA signal transduction, and its crosstalk with other hormones, such as gibberellin acid (GA), ethylene (ET) and salicylic acid (SA), explained the elevation of most of the differential expressed genes related to taxol biosynthesis pathway. Moreover, TF (transcriptional factor)-encoding genes, including MYBs, ethylene-responsive transcription factors (ERFs) and basic/helix-loop-helix (bHLH), were detected as differential expressed genes after KL27-FB treatment, further suggested that the regulation of hormone signaling on genes of taxol biosynthesis was mediated by TFs. CONCLUSIONS: Our results indicated that fermentation broth of endophytic fungus KL27-FB could effectively enhance the accumulation of taxol in T. chinensis needles by regulating the phytohormone metabolism and signal transduction and further up-regulating the expression of multiple key genes involved in taxol biosynthesis. This study provides new insight into the regulatory mechanism of how endophytic fungus promotes the production and accumulation of taxol in Taxus sp.


Assuntos
Ascomicetos/fisiologia , Endófitos/fisiologia , Regulação da Expressão Gênica de Plantas , Paclitaxel/biossíntese , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais , Taxus/metabolismo , Genes de Plantas , Paclitaxel/metabolismo , Taxus/microbiologia , Regulação para Cima
7.
BMC Genomics ; 23(1): 5, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34983375

RESUMO

BACKGROUND: Aspergillus flavus, one of the causative agents of human fungal keratitis, can be phagocytosed by human corneal epithelial (HCE) cells and the conidia containing phagosomes mature into phagolysosomes. But the immunological responses of human corneal epithelial cells interacting with A. flavus are not clear. In this study, we report the expression of immune response related genes of HCE cells exposed to A. flavus spores using targeted transcriptomics. METHODS: Human corneal epithelial cell line and primary cultures were grown in a six-well plate and used for coculture experiments. Internalization of the conidia was confirmed by immunofluorescence microscopy of the colocalized endosomal markers CD71 and LAMP1. Total RNA was isolated, and the quantity and quality of the isolated RNA were assessed using Qubit and Bioanalyzer. NanoString nCounter platform was used for the analysis of mRNA abundance using the Human Immunology panel. R-package and nSolver software were used for data analysis. KEGG and FunRich 3.1.3 tools were used to analyze the differentially expressed genes. RESULTS: Different morphotypes of conidia were observed after 6 h of coculture with human corneal epithelial cells and found to be internalized by epithelial cells. NanoString profiling showed more than 20 differentially expressed genes in immortalized human corneal epithelial cell line and more than ten differentially expressed genes in primary corneal epithelial cells. Distinct set of genes were altered in their expression in cell line and primary corneal epithelial cells. KEGG pathway analysis revealed that genes associated with TNF signaling, NF-KB signaling, and Th17 signaling were up-regulated, and genes associated with chemokine signaling and B cell receptor signaling were down regulated. FunRich pathway analysis showed that pathways such as CDC42 signaling, PI3K signaling, and Arf6 trafficking events were activated by the clinical isolates CI1123 and CI1698 in both type of cells. CONCLUSIONS: Combining the transcript analysis data from cell lines and primary cultures, we showed the up regulation of immune defense genes in A. flavus infected cells. At the same time, chemokine signaling and B cell signaling pathways are downregulated. The variability in the expression levels in the immortalized cell line and the primary cultures is likely due to the variable epigenetic reprogramming in the immortalized cells and primary cultures in the absence of any changes in the genome. It highlights the importance of using both cell types in host-pathogen interaction studies.


Assuntos
Aspergillus flavus , Células Epiteliais/imunologia , Regulação da Expressão Gênica/imunologia , Aspergillus flavus/genética , Linhagem Celular , Quimiocinas/imunologia , Córnea/citologia , Córnea/microbiologia , Células Epiteliais/microbiologia , Humanos , Imunidade , Transdução de Sinais , Esporos Fúngicos
8.
Pediatr Clin North Am ; 69(1): 65-77, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34794677

RESUMO

Salmonella is a gram-negative, motile, nonsporulating, facultative anaerobic bacillus, belongs to the family Enterobacteriaceae. The bacteria were first identified in 1884. It is transmitted through direct contact with an infected person or indirect contact by the consumption of contaminated food and water. More than 2500 serotypes of Salmonella enterica have been identified but less than 100 serotypes are known to cause infections in humans. S. enterica serovar typhi (S. typhi) and S. enterica serovar paratyphi (S. paratyphi A B C) cause enteric fever, whereas nontyphoidal Salmonella serotypes (NTS) cause diarrhea. NTS commonly presents with gastroenteritis and is a self-limiting disease. Enteric fever is a potentially life-threatening acute febrile systemic infection and is diagnosed by isolating a pathogen on culture. With the emergence of the extensive drug-resistant (XDR) S. typhi clone, limited treatment options are available. Vaccination of persons at risk, improvement of sanitation, promotion of food hygiene, and detection and control of chronic carriers are essential preventive control measures of enteric fever.


Assuntos
Infecções por Salmonella/epidemiologia , Infecções por Salmonella/terapia , Febre Tifoide/epidemiologia , Febre Tifoide/terapia , Antibacterianos/uso terapêutico , Fezes/microbiologia , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/terapia , Humanos , Higiene , Salmonella/genética , Infecções por Salmonella/microbiologia , Infecções por Salmonella/prevenção & controle , Salmonella typhi/isolamento & purificação , Sorogrupo , Febre Tifoide/microbiologia , Febre Tifoide/prevenção & controle , Vacinas Tíficas-Paratíficas/uso terapêutico , Microbiologia da Água
9.
J Sci Food Agric ; 102(2): 540-549, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34146349

RESUMO

BACKGROUND: Pasture farming in south-western Australia is challenged by nutrient-poor soils. We assessed the impact of microbial consortium inoculant (MI) and rock mineral fertiliser (MF) on growth, nutrient uptake, root morphology, rhizosphere carboxylate exudation and mycorrhizal colonisation in three pasture grasses - tall fescue (Festuca arundinacea L.), veldt grass (Ehrharta calycina Sm.) and tall wheatgrass (Thinopyrum ponticum L.) grown in low-phosphorus (P) sandy soil in a glasshouse for 30 and 60 days after sowing (DAS). RESULTS: Veldt grass produced the highest specific root length and smallest average root diameter in both growth periods, and had similar shoot weight, root surface area and fine root length (except at 30 DAS) to tall fescue. Compared with the control, MI alone or combined with MF significantly increased shoot and root biomass (except root biomass at 30 DAS), likely due to the significant increases in root surface area and fine root length. Plants supplied with MI + MF had higher shoot N and P contents than those in the MI and the control treatments at 60 DAS. Malate, citrate and trans-aconitate were the major rhizosphere carboxylates exuded at both 30 and 60 DAS. Malate exudation varied among species and treatments in both growth periods, but citrate exudation was consistently higher in the low-P treatments (control and MI) than the MF and MI + MF treatments. CONCLUSION: Microbial consortium inoculant can positively influence pasture production in low-P soil by increasing root surface area and fine root length, whereas exudation of nutrient-mobilising carboxylates (citrate) is dependent more on soil P supply than microbial consortium inoculant. © 2021 Society of Chemical Industry.


Assuntos
Inoculantes Agrícolas/crescimento & desenvolvimento , Micorrizas/crescimento & desenvolvimento , Fósforo/análise , Exsudatos de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Poaceae/microbiologia , Ácidos Carboxílicos/análise , Ácidos Carboxílicos/metabolismo , Fertilizantes/análise , Consórcios Microbianos , Fósforo/metabolismo , Exsudatos de Plantas/análise , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Poaceae/química , Poaceae/crescimento & desenvolvimento , Poaceae/metabolismo , Rizosfera , Solo/química
10.
J Sci Food Agric ; 102(2): 597-606, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34148242

RESUMO

BACKGROUND: With the development of intensive farming, long-term exposure of pigs to poor light conditions is not conducive to the production of vitamin D3 , and vitamin D3 deficiency could affect absorption and metabolism of calcium (Ca) and phosphorus (P). 25-Hydroxyvitamin D3 (25OHD3 ) has higher bioactivity than regular vitamin D3 . This study investigated the effects of 25OHD3 on performance, serum parameters, fecal microbiota, and metabolites in weaned piglets fed with low Ca-P diet. RESULTS: It was found that a low Ca-P diet supplemented with 50 µg/kg 25OHD3 (NC + 25-D) improved (P < 0.05) average daily gain (ADG) in phase 2 and in the overall period of the experiment, and increased (P < 0.05) the immunoglobulin G (IgG), immunoglobulin A (IgA), catalase (CAT), bone-specific alkaline phosphatase (BALP), and osteocalcin (OC) serum content on day 28 compared with a low Ca-P diet (NC), but no differences were observed between a normal Ca-P diet (PC) and the NC + 25-D diet. Compared with NC, the abundance of Firmicutes was higher (P < 0.05) in PC and NC + 25-D. NC + 25-D decreased (P < 0.05) the abundance of Streptococcaceae compared with PC and NC, and increased (P < 0.05) the abundance of Lachnospiraceae compared with NC. Serum 25OHD3 was negatively correlated with the abundance of fecal Streptococcaceae (P < 0.05), and positively correlated with the abundance of fecal Lachnospiraceae (P < 0.05). CONCLUSION: Supplementation of 25OHD3 in a low Ca-P diet improved serum immunity, bone biochemical parameters, and fecal microbiota such as decreased Streptococcaceae abundance and increased Lachnospiraceae abundance, which could subsequently promote growth of piglets. The effects were similar to that of a normal Ca-P diet. © 2021 Society of Chemical Industry.


Assuntos
Calcifediol/metabolismo , Fezes/microbiologia , Microbioma Gastrointestinal , Suínos/crescimento & desenvolvimento , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Desenvolvimento Ósseo , Osso e Ossos/metabolismo , Cálcio/análise , Cálcio/metabolismo , Suplementos Nutricionais/análise , Feminino , Masculino , Fósforo/análise , Fósforo/metabolismo , Suínos/sangue , Suínos/metabolismo , Suínos/microbiologia , Desmame
11.
J Sci Food Agric ; 102(2): 607-616, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34151432

RESUMO

BACKGROUND: Maternal nutrition during gestation and lactation is essential for offspring's health. The present study aimed to investigate the effects of betaine hydrochloride addition to sow diets during gestation and lactation on suckling piglet's immunity and intestine microbiota composition. Forty Bama mini-pigs were randomly allocated into two groups and fed a basal diet (control group) and a basal diet supplemented with 3.50 kg ton-1 betaine hydrochloride (betaine group) from day 3 after mating to day 21 of lactation. After 21 days of the delivery, 12 suckling piglets from each group with similar body weight were selected for sample collection. RESULTS: The results showed that maternal betaine hydrochloride addition decreased (P < 0.05) the plasma levels of interleukin (IL)-1ß, IL-2, IL-6, and tumor necrosis factor-α in suckling piglets. Furthermore, dietary betaine hydrochloride addition in sow diets increased (P < 0.05) the villus height (VH) and VH to crypt depth ratio in the jejunum and ileum of suckling piglets. In the piglets' intestinal microbiota community, the relative abundances of Roseburia (P < 0.05) and Clostridium (P = 0.059) were lower in the betaine group compared to those in the control group. Moreover, betaine hydrochloride addition in sow diets decreased the colonic tyramine (P = 0.091) and skatole (P = 0.070) concentrations in suckling piglets. CONCLUSION: Betaine hydrochloride addition in sow diets enhanced the intestinal morphology, improved immunity, and altered intestinal microbiota of suckling piglets. These findings indicated that betaine hydrochloride addition in sow diets during gestation and lactation will impact suckling piglets' health. © 2021 Society of Chemical Industry.


Assuntos
Betaína/metabolismo , Microbioma Gastrointestinal , Porco Miniatura/embriologia , Ração Animal/análise , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/imunologia , Animais Recém-Nascidos/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Suplementos Nutricionais/análise , Feminino , Interleucinas/sangue , Lactação , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Suínos , Porco Miniatura/sangue , Porco Miniatura/imunologia , Porco Miniatura/microbiologia , Fator de Necrose Tumoral alfa/sangue
12.
J Sci Food Agric ; 102(2): 664-672, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34165824

RESUMO

BACKGROUND: The use of indigenous selected starters in winemaking is gaining interest due to certain advantages for the sensory quality of the wine. The present work shows the results of a laboratory experiment in which the influence of selected indigenous yeasts on the colour characteristics of Pinot Noir was studied with the use of high hydroxycinnamate decarboxylase activity yeasts. Pichia guilliermondii ZIM624 and Wickerhamomyces anomalus S138 yeasts were used in sequential fermentation with two strains of Saccharomyces cerevisiae, the native ZIM2180 strain and commercial Fermol Premier Cru (FPC). RESULTS: In co-inoculation fermentations, non-Saccharomyces yeasts decreased colour intensity (on average by 25.5%). In wines fermented with ZIM624, the concentration of vinylphenolic pyranoanthocyanins increased (average concentration 1.5 mg L-1 ). However, vitisin concentration was significantly higher in S138 + FPC fermentation (1.3 mg L-1 and an average of 0.9 mg L-1 , respectively). Pinot Noir wines fermented with only ZIM2180 and sequential inoculation of ZIM624 + ZIM2180 resulted in significantly higher colour intensity (6.1 ± 0.0 AU and 4.4 ± 0.0 AU, respectively) and lower wine hue parameters compared to other wines. Sensory evaluation also showed that both wines had the highest perceived colour intensity and purple colour suggesting improvement in wine quality parameters. CONCLUSIONS: The results confirmed that selected indigenous starters made out of Saccharomyces and non-Saccharomyces yeasts can alter Pinot Noir wine colour parameters and improve wine colour properties. Those yeasts properties should be investigated prior to the development of new commercial starters but also be considered in large scale spontaneous fermentations of low colour intensity red wines like Pinot Noir. © 2021 Society of Chemical Industry.


Assuntos
Vitis/microbiologia , Vinho/análise , Leveduras/metabolismo , Cor , Fermentação , Microbiologia de Alimentos , Vitis/metabolismo , Vinho/microbiologia , Leveduras/classificação
13.
J Sci Food Agric ; 102(2): 680-687, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34171121

RESUMO

BACKGROUND: The brown rot fungus, Gnomoniopsis castanea, is the main organism responsible for the outbreak of chestnut postharvest decay that is threatening the sustainability of the chestnut market in Europe. Currently, no specific strategy is available to mitigate the impact and remediate the high losses of fruits in postharvest storage. In the present study, the different phases of chestnut handling in a standard facility plant were analyzed by evaluating the amount of fruit rot and infection by G. castanea at each phase. RESULTS: The warm bath (48 °C) was identified as the critical phase, requiring strict parametrization to effectively inactivate G. castanea in fruits. Laboratory tests indicated that maintaining fruits at 50 °C for a maximum of 45 min provided optimal conditions to completely inactivate G. castanea inoculum during postharvest handling. However, the warm bath at 50 °C and over was not effective in inactivating the complex of fungal taxa responsible for contamination and development of molds. Higher temperatures and extended treatment times caused significant losses in fruit quality, as indicated by taste panel evaluation. Upscaling of postharvest facilities is discussed and critically evaluated. CONCLUSION: The warm bath (50 °C for 45 min) is effective in completely inactivating G. castanea in fruits but did not reduce the impacts of the complex of molds responsible for external contamination and mycotoxin production. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ascomicetos/fisiologia , Fagaceae/microbiologia , Conservação de Alimentos/métodos , Doenças das Plantas/microbiologia , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Fagaceae/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Frutas/microbiologia , Temperatura Alta , Doenças das Plantas/prevenção & controle
14.
J Sci Food Agric ; 102(2): 862-867, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34173230

RESUMO

BACKGROUND: As a natural food additive, exopolysaccharide (EPS) produced by Streptococcus thermophilus can improve product viscosity and texture. The protein EpsA is a putative pathway-specific transcriptional regulator for EPS biosynthesis in S. thermophilus. RESULTS: According to comparative analysis of EPS biosynthetic gene clusters, a conserved region of epsA (609 bp) was employed to design primer pair epsA-F/R as a molecular marker for the isolation of EPS-producing (EPS+ ) S. thermophilus. Two EPS+ S. thermophiles strains, AR333 and S-3, were band-positive, whereas Lactococcus lactis NZ9000 (non-EPS-producing, EPS- ), Lactobacillus casei LC2W (EPS+ ) and L. plantarum AR113 (EPS+ ) were negative by polymerase chain reaction (PCR) amplicon bands using the epsA probe. This indicated good specificity of the epsA probe to EPS+ S. thermophilus. Moreover, based on PCR screening with the epsA probe, 23 positive strains were isolated and identified as S. thermophilus from our microbial library and natural fermented milk with 141.3-309.2 mg L-1 of EPS production, demonstrating the validity of our molecular marker screening method. CONCLUSION: The designed molecular marker of epsA can rapidly screen EPS+ S. thermophilus, which has potential application in the dairy and other food industries. © 2021 Society of Chemical Industry.


Assuntos
Polissacarídeos Bacterianos/biossíntese , Streptococcus thermophilus/genética , Streptococcus thermophilus/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bovinos , Produtos Fermentados do Leite/microbiologia , Fermentação , Marcadores Genéticos , Família Multigênica , Streptococcus thermophilus/metabolismo
15.
J Sci Food Agric ; 102(2): 696-706, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34173241

RESUMO

BACKGROUND: Microorganism for biological control of fruit diseases is an eco-friendly alternative to the use of chemical fungicides. RESULTS: This is the first study evaluating the electrospraying process to encapsulate the biocontrol yeast Meyerozyma caribbica. The effect of encapsulating material [Wey protein concentrate (WPC), Fibersol® and Trehalose], its concentration and storage temperature on the cell viability of M. caribbica, and in vitro and in vivo control of Colletotrichum gloeosporioides was evaluated. The processing with commercial resistant maltodextrin (Fibersol®) 30% (w/v) as encapsulating material showed the highest initial cell viability (95.97 ± 1.01%). The storage at 4 ± 1 °C showed lower losses of viability compared to 25 ± 1 °C. Finally, the encapsulated yeast with Fibersol 30% w/v showed inhibitory activity against anthracnose in the in vitro and in vivo tests, similar to yeast fresh cells. CONCLUSION: Electrospraying was a highly efficient process due to the high cell viability, and consequently, a low quantity of capsules is required for the postharvest treatment of fruits. Additionally, the yeast retained its antagonistic power during storage. © 2021 Society of Chemical Industry.


Assuntos
Agentes de Controle Biológico/química , Agentes de Controle Biológico/farmacologia , Carica/microbiologia , Colletotrichum/efeitos dos fármacos , Composição de Medicamentos/métodos , Mangifera/microbiologia , Saccharomycetales/química , Antibiose , Colletotrichum/crescimento & desenvolvimento , Composição de Medicamentos/instrumentação , Frutas/microbiologia , Viabilidade Microbiana , Saccharomycetales/fisiologia
16.
J Sci Food Agric ; 102(2): 794-800, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34223648

RESUMO

BACKGROUND: Two edible coating (EC) emulsions based on potato starch (F6 and F10) alone or formulated with sodium benzoate (SB, 2% w/w) (F6/SB and F10/SB) were evaluated to maintain postharvest quality of cold-stored 'Fino' lemons and control sour rot on lemons artificially inoculated with Geotrichum citri-aurantii. Previous research showed the potential of these ECs to improve the storability of 'Orri' mandarins and reduce citrus green and blue molds caused by Penicillum digitatum and Penicillium italicum, respectively. RESULTS: The coatings F6/SB and F10/SB significantly reduced sour rot incidence and severity compared to uncoated control samples on lemons incubated at 28 °C for 4 and 7 days. The F6/SB coating reduced weight loss and gas exchange compared to uncoated fruit after 2 and 4 weeks of storage at 12 °C plus a shelf life of 1 week at 20 °C, without adversely affecting the lemon physicochemical quality. CONCLUSION: Overall, the F6/SB coating formulation, composed of pregelatinized potato starch, glyceryl monostearate, glycerol, emulsifiers and SB, with a total solid content of 5.5%, showed the best results in reducing citrus sour rot and maintaining the postharvest quality of cold-stored 'Fino' lemons. Therefore, it showed potential as a new cost-effective postharvest treatment suitable to be included in integrated disease management programs for citrus international markets with zero tolerance to chemical residues. © 2021 Society of Chemical Industry.


Assuntos
Citrus/microbiologia , Conservação de Alimentos/métodos , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Geotrichum/efeitos dos fármacos , Doenças das Plantas/microbiologia , Amido/química , Amido/farmacologia , Citrus/química , Composição de Medicamentos , Armazenamento de Alimentos , Frutas/química , Frutas/microbiologia , Geotrichum/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle , Benzoato de Sódio/química , Solanum tuberosum/química
18.
Cardiovasc Pathol ; 56: 107382, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34478860

RESUMO

BACKGROUND: Histopathologic differentiation of bacterial endocarditis from yeast-like fungal endocarditis is usually straightforward; however, an underappreciated phenomenon is the effect of antimicrobial therapy on bacterial size, shape and septa (cross-wall) formation resulting in bacterial forms that mimic yeast-like fungi. In this article we illustrate the alterations that occur in antibiotic-treated Staphylococcus aureus endocarditis and compare these changes to histopathologic findings in unaltered S. aureus and Histoplasma endocarditis, respectively. METHODS: Resected valves from three cases of endocarditis were compared based on the type ofinflammatory reaction, organism morphology and culture results. Case 1 was S. aureus endocarditis initially misclassified as Histoplasma due to its atypical morphologic and histopathologic features. The two cases included for comparison were an S. aureus endocarditis with more classic features and an Histoplasma capsulatum endocarditis. Hematoxylin and eosin (H&E), Gram, periodic acid Schiff (PAS), Gomori-Grocott methenamine silver stains (GMS), and culture results were compared in all cases. Molecular and immunohistochemistry tests were used for confirmation of first case. High power oil-immersion was used to visualize organisms' characteristics in all three cases. RESULTS: Case 1 and Case 3 (Histoplasma-infected valves) had fibrinous exudates with scattered macrophages. The microorganisms observed in the first case of methicillin-sensitive S. aureus (MSSA) were ∼ 2-3 µm by GMS stain and had prominent septations. Histoplasma yeast were round to oval, ∼ 3-4 µm in size and demonstrated budding. S. aureus without alterations were round, ∼ 1 µm in size, and lacked prominent septations. Necrotizing purulent inflammation was present in the unaltered case of MSSA. The MSSA case with alterations from antibiotic treatment did not stain well with the Gram stain and organisms were best visualized with the PAS and GMS stains. CONCLUSIONS: Antibiotic therapy for bacterial endocarditis can alter the inflammatory reaction to infection, bacterial size, septa formation, and staining characteristics. Knowledge of these therapy-related effects and use of high-power magnification helps to avoid misclassification as yeast-like fungi.


Assuntos
Endocardite Bacteriana , Endocardite , Fungos , Anti-Infecciosos/farmacologia , Diagnóstico Diferencial , Endocardite/microbiologia , Endocardite/patologia , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/patologia , Humanos , Staphylococcus aureus/efeitos dos fármacos
19.
Int J Cancer ; 150(1): 18-27, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34449868

RESUMO

Helicobacter pylori (H. pylori) infection is considered the leading cause of gastric cancer. Gastric cancer is currently a common cancer with high incidence and mortality rates, but it is expected that the incidence rate will gradually decrease as the H. pylori infection prevalence decreases in the future. When evaluating the effectiveness of gastric cancer prevention strategies, it is essential to note the differences in long-term cumulative risks between H. pylori-infected and uninfected populations, but this has not yet been precisely evaluated. In our study, we aimed to estimate the cumulative incidence risks of developing gastric cancer from birth to 85 years among H. pylori-infected and uninfected populations by using population-based cancer registry data and birth year-specific H. pylori infection prevalence rates. Death from gastric cancer and other causes of death were considered in the estimations of the adjusted cumulative incidence risks stratified by sex and H. pylori infection status. After performing 5000 Monte Carlo simulations with repeated random sampling using observed cancer incidence in selected three prefectures (Fukui, Nagasaki, Yamagata) of prefectural population-based cancer registry in Japan, the mean adjusted cumulative incidence risk for gastric cancer in the H. pylori-infected population was 17.0% for males and 7.7% for females and 1.0% for males and 0.5% for females in the uninfected population. These results calculated with Japanese cancer registry data may be useful in considering and evaluating future prevention strategies for gastric cancer in Japan.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori/isolamento & purificação , Método de Monte Carlo , Neoplasias Gástricas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Seguimentos , Infecções por Helicobacter/microbiologia , Humanos , Incidência , Lactente , Recém-Nascido , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/microbiologia , Adulto Jovem
20.
Int J Cancer ; 150(2): 243-252, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34498732

RESUMO

Gastric atrophy caused by Helicobacter pylori infection was suggested to influence the risk of adenocarcinoma of the esophagogastric junction (AEGJ), however, the evidence remains limited. We aimed to examine the associations of H. pylori infection and gastric atrophy (defined using serum pepsinogen [PG] I to PGII ratio) with AEGJ risk, based on a population-based case-control study in Taixing, China (2010-2014), with 349 histopathologically confirmed AEGJ cases and 1859 controls. We explored the potential effect modification by H. pylori serostatus and sex on the association of serum PGs with AEGJ risk. We used unconditional logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs). H. pylori seropositivity was associated with an elevated AEGJ risk (OR = 1.95, 95% CI: 1.47-2.63). Neither CagA-positive nor VacA-positive strains dramatically changed this association. Gastric atrophy (PGI/PGII ratio ≤4) was positively associated with AEGJ risk (OR = 2.36, 95% CI: 1.72-3.22). The fully adjusted ORs for AEGJ progressively increased with the increasing levels of PGII (P-trend <.001). H. pylori showed nonsignificant effect modification (P-interaction = .385) on the association of gastric atrophy with AEGJ. In conclusion, H. pylori and gastric atrophy were positively associated with AEGJ risk. These results may contribute evidence to the ongoing research on gastric atrophy-related cancers and guide the prevention and control of AEGJ.


Assuntos
Adenocarcinoma/epidemiologia , Neoplasias Esofágicas/epidemiologia , Junção Esofagogástrica/patologia , Gastrite Atrófica/epidemiologia , Infecções por Helicobacter/complicações , Helicobacter pylori/isolamento & purificação , Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China/epidemiologia , Neoplasias Esofágicas/microbiologia , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/microbiologia , Feminino , Seguimentos , Gastrite Atrófica/microbiologia , Gastrite Atrófica/patologia , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...