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1.
Artigo em Inglês | MEDLINE | ID: mdl-38597850

RESUMO

OBJECTIVE: To describe the patterns of diabetic ketoacidosis (DKA) occurrence in children newly diagnosed with type 1 diabetes (T1DM) across several Latin American pediatric diabetes centers from 2018 to 2022. METHODS: A retrospective chart review included children under 18 with new-onset T1DM from 30 Latin American pediatric diabetes centers (Argentina, Chile, and Peru) between 30 December 2018 and 30 December 2022. Multiple logistic regression models examined the relationships between age, gender, medical insurance, BMI, and DKA at new-onset T1DM. As far as we know, there are no large studies in Latin American countries exploring the patterns of DKA in new-onset T1DM. RESULTS: A total of 2,026 (983 females) children, median age 9.12 (5.8 -11.7) years with new-onset-T1DM were included. Approximately 50% had no medical insurance. Mean glucose values were 467 mg/dL, pH 7.21, bicarbonate 13 mEq/L, HbA1c 11.3%, and BMI 18. The frequency of DKA was 1,229 (60.7%), out of which only 447 (36%) were severe. There was a significant decrease in the frequency of DKA as age increased: 373 (70.2%) in children under 6, 639 (61.6%) in those between 6 and 12, 217 and (47.5%) in those over 12. Children with medical insurance (58.8%) had a significantly lower frequency of DKA than those without (62.7%). The multiple logistic regression models showed that DKA was significantly and inversely associated with age [OR, 0.72 (95% CI 0.60-0.86)], BMI [OR, 0.95 (95% CI 0.92-0.99)], and medical insurance [OR, 0.75 (95% CI 0.60-0.94)] adjusted for sex. CONCLUSION: Latin American children with new-onset T1DM exhibited a substantial occurrence of DKA. Younger ages and the lack of medical insurance were significantly associated with DKA in new-onset T1DM.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37605998

RESUMO

Strain HF14-78462T is an environmental bacterium found in clinical samples from an immunocompromized patient in 2014 at Hospital Universitari i Politècnic La Fe (Valencia, Spain). Phenotypically, strain HF14-78462T cells were Gram-stain-negative, aerobic, non-spore forming and non-motile small rods which formed mucous and whitish-translucent colonies when incubated at 20-36 °C. Phylogenetic analyses based on the 16S rRNA genes and the whole genomes of closest sequenced relatives confirmed that strain HF14-78462T is affiliated with the genus Starkeya. The strain was oxidase, catalase and urease positive; but indole, lysine decarboxylase, ornithine decarboxylase and DNase negative, did not produce H2S and was able to utilize a wide variety of carbon sources including acetamide, adonitol, amygdalin, l-arabinose, citric acid, glucose, mannitol and melibiose. Unlike Starkeya novella and Starkeya koreensis, strain HF14-78462T failed to grow in thiosulphate-oxidizing media and had a narrower temperature growth range. Its genome was characterized by a size of 4.83 Mbp and a C+G content of 67.75 mol%. Major fatty acids were C18:1 ω7c, cyclo C19 : 0 and C16 : 0, its polar acids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and an aminophospholipid; while the ubiquinones were Q9 (1.8 %) and Q10 (98.2 %). Digital DNA-DNA hybridization values were 41 and 41.4 against S. novella and S. koreensis, respectively, while average nucleotide identity values were around 84 %. Phenotypic, average nucleotide identity and phylogenomic comparative studies suggest that strain HF14-78462T is a new representative of the genus Starkeya and the name Starkeya nomas sp. nov. is proposed. The type strain is HF14-78462T (=CECT 30124T=LMG 31874T).


Assuntos
Ácidos Graxos , Noma , Humanos , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Bactérias
4.
Animals (Basel) ; 13(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36766216

RESUMO

Canine chronic inflammatory enteropathy implicates multifactorial pathogenesis where immunological dysregulation and gut microbiota changes have a central role. Most sequencing-based taxonomic studies have been focused on the fecal microbiota. However, the analysis of these samples does not provide complete information regarding the composition of the small intestine affected by this canine disease. Therefore, in this study, we aimed to characterize the intestinal bacterial microbiota in dogs with inflammatory bowel disease (IBD) (n = 34) by means of duodenal biopsies and fecal samples collected at the time of the diagnosis and to compare those to a group of healthy dogs (n = 12) using the 16S ribosomal RNA (16S rRNA) gene-targeted sequencing (Illumina MiSeq platform). Our study showed that IBD dogs presented differences in the fecal bacterial communities when compared with healthy dogs, with a lower relative abundance of Prevotellaceae (p = 0.005), Prevotella (p = 0.002), and Prevotellaceae Ga6A1 group (0.006); Erysipelotrichales (p = 0.019), Candidatus Stoquefichus (p < 0.001), Erysipelotrichaceae (p = 0.011), and Allobaculum (p = 0.003); Lachnospiraceae NK4A136 group (p = 0.015), Sellimonas (p = 0.042), Oscillospirales (p = 0.037), Oscillospiraceae UCG-005 (p < 0.001), Faecalibacterium (p = 0.028), and Fournierella (p = 0.034); Acidaminococcales, Acidaminococcaceae, and Phascolarctobacterium (p = 0.001); Aeromonadales (p = 0.026), Succinivibrionaceae (p = 0.037), and Succinivibrio (p = 0.031). On the other hand, a higher relative abundance of Enterococcaceae (Enterococcus; p = 0.003), Streptococcaceae (Streptococcus, p = 0.021), Enterobacterales (p = 0.027), Enterobacteriaceae (p = 0.008), and Escherichia-Shigella (p = 0.011) was detected. Moreover, when evaluating α-diversity, the dogs with IBD showed lower diversity in terms of richness and abundance of species (observed species [p = 0.031] and Shannon index [p = 0.039]). Furthermore, fecal microbiota in dogs with IBD was significantly different from healthy dogs (p = 0.006). However, only a few taxa relative abundance shifts (lower Rubrobacteria, Rubrobacterales, Rubrobacteriaceae, and Rubrobacter [p = 0.002]; Cyanobacteria [p = 0.010], Vampirivibrionia, Obscuribacterales, and Obscuribacteraceae [p = 0.005]; Neisseriaceae [p = 0.004] and Conchiformibius [p = 0.003]) were observed when assessing duodenal-associated microbiota of dogs with IBD. Thus, even if the bowel inflammation mainly affects the small intestine in the IBD-affected dogs of the study, fecal specimens may constitute a better sample due not only to their easy availability but also in terms of searching for bacterial taxa as biomarkers for canine IBD. The use of different diets in the study can also have a partial influence on the microbiota composition. Future studies encompassing multi-omics approaches should evaluate the functionality in both levels to unravel the pathophysiology of canine IBD.

5.
Microbiol Resour Announc ; 12(2): e0104822, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36651741

RESUMO

Salmonella enterica is one of the most common causes of foodborne diseases. Bacteriophages provide an option to reduce the presence of Salmonella. Here, we describe the isolation of two lytic Salmonella bacteriophages. The complete genomes were annotated and show similarity to that of the lytic phage NBSal001, in the Drexlerviridae family.

6.
Diabetes Res Clin Pract ; 192: 110110, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36183869

RESUMO

AIMS: To evaluate access to screening tools for monogenic diabetes in paediatric diabetes centres across the world and its impact on diagnosis and clinical outcomes of children and youth with genetic forms of diabetes. METHODS: 79 centres from the SWEET diabetes registry including 53,207 children with diabetes participated in a survey on accessibility and use of diabetes related antibodies, c-peptide and genetic testing. RESULTS: 73, 63 and 62 participating centres had access to c-peptide, antibody and genetic testing, respectively. Access to antibody testing was associated with higher proportion of patients with rare forms of diabetes identified with monogenic diabetes (54 % versus 17 %, p = 0.01), lower average whole clinic HbA1c (7.7[Q1,Q2: 7.3-8.0]%/61[56-64]mmol/mol versus 9.2[8.6-10.0]%/77[70-86]mmol/mol, p < 0.001) and younger age at onset (8.3 [7.3-8.8] versus 9.7 [8.6-12.7] years p < 0.001). Additional access to c-peptide or genetic testing was not related to differences in age at onset or HbA1c outcome. CONCLUSIONS: Clinical suspicion and antibody testing are related to identification of different types of diabetes. Implementing access to comprehensive antibody screening may provide important information for selecting individuals for further genetic evaluation. In addition, worse overall clinical outcomes in centers with limited diagnostic capabilities indicate they may also need support for individualized diabetes management. TRIAL REGISTRATION: NCT04427189.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus , Adolescente , Criança , Humanos , Peptídeo C , Diabetes Mellitus/diagnóstico , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Hemoglobinas Glicadas/análise , Programas de Rastreamento , Sistema de Registros
7.
Mol Biol Evol ; 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35724423

RESUMO

Most humans carry mites in the hair follicles of their skin for their entire lives. Follicular mites are the only metazoans tha continuously live on humans. We propose that Demodex folliculorum (Acari) represents a transitional stage from a host-injuring obligate parasite to an obligate symbiont. Here, we describe the profound impact of this transition on the genome and physiology of the mite. Genome sequencing revealed that the permanent host association of D. folliculorum led to an extensive genome reduction through relaxed selection and genetic drift, resulting in the smallest number of protein-coding genes yet identified among panarthropods. Confocal microscopy revealed that this gene loss coincided with an extreme reduction in the number of cells. Single uninucleate muscle cells are sufficient to operate each of the three segments that form each walking leg. While it has been assumed that the reduction of the cell number in parasites starts early in development, we identified a greater total number of cells in the last developmental stage (nymph) than in the terminal adult stage, suggesting that reduction starts at the adult or ultimate stage of development. This is the first evolutionary step in an arthropod species adopting a reductive, parasitic or endosymbiotic lifestyle. Somatic nuclei show underreplication at the diploid stage. Novel eye structures or photoreceptors as well as a unique human host melatonin-guided day/night rhythm are proposed for the first time. The loss of DNA repair genes coupled with extreme endogamy might have set this mite species on an evolutionary dead-end trajectory.

8.
Front Microbiol ; 13: 858983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35479634

RESUMO

The current theoretical proposals of minimal genomes have not attempted to outline the essential machinery for proper translation in cells. Here, we present a proposal of a minimal translation machinery based on (1) a comparative analysis of bacterial genomes of insects' endosymbionts using a machine learning classification algorithm, (2) the empiric genomic information obtained from Mycoplasma mycoides JCVI-syn3.0 the first minimal bacterial genome obtained by design and synthesis, and (3) a detailed functional analysis of the candidate genes based on essentiality according to the DEG database (Escherichia coli and Bacillus subtilis) and the literature. This proposed minimal translational machinery is composed by 142 genes which must be present in any synthetic prokaryotic cell designed for biotechnological purposes, 76.8% of which are shared with JCVI-syn3.0. Eight additional genes were manually included in the proposal for a proper and efficient translation.

9.
Front Microbiol ; 12: 687971, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512566

RESUMO

The rapidly increasing global population and anthropogenic climate change have created intense pressure on agricultural systems to produce increasingly more food under steadily challenging environmental conditions. Simultaneously, industrial agriculture is negatively affecting natural and agricultural ecosystems because of intensive irrigation and fertilization to fully utilize the potential of high-yielding cultivars. Growth-promoting microbes that increase stress tolerance and crop yield could be a useful tool for helping mitigate these problems. We investigated if commercially grown almonds might be a resource for plant colonizing bacteria with growth promotional traits that could be used to foster more productive and sustainable agricultural ecosystems. We isolated an endophytic bacterium from almond leaves that promotes growth of the model plant Arabidopsis thaliana. Genome sequencing revealed a novel Erwinia gerundensis strain (A4) that exhibits the ability to increase access to plant nutrients and to produce the stress-mitigating polyamine spermidine. Because E. gerundensis is known to be able to colonize diverse plant species including cereals and fruit trees, A4 may have the potential to be applied to a wide variety of crop systems.

10.
Rev. Soc. Argent. Diabetes ; 55(2): 70-74, mayo - ago. 2021. ilus
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1395550

RESUMO

Los pacientes en estado crítico con COVID-19 sufren hiperglucemias sostenidas de difícil manejo. A esto se suma el desafío de minimizar la exposición al contagio. En el presente artículo analizamos la evolución metabólica de dos pacientes pediátricos con COVID-19 admitidos en unidad de cuidados intensivos (UCI) para pacientes COVID-19 del Hospital "Prof. Dr. Juan P. Garrahan" de la Ciudad Autónoma de Buenos Aires, Argentina, que requirieron tratamiento con insulina endovenosa y cuya glucemia fue monitoreada de manera remota con la plataforma InsuMate® desarrollada en la Universidad Nacional de La Plata. Los pacientes requirieron tasas de infusión de insulina en dosis marcadamente mayores que las de otros pacientes críticos que impresionaron relacionadas con los valores de marcadores de inflamación. La infusión pudo ajustarse con cuatro monitoreos diarios de glucosa y las métricas obtenidas con el monitor de glucosa. El uso del sistema de monitoreo remoto continuo de glucosa permitió disminuir la frecuencia de monitoreo glucémico durante el tratamiento.


Critically ill patients with COVID-19 suffer from sustained hyperglycemia that is difficult to manage. Added to this is the challenge of minimizing exposure to contagion. In this article we analyze the metabolic evolution of two pediatric patients with COVID-19 admitted to the intensive care unit (ICU) for COVID-19 patients at the Hospital "Prof. Dr. Juan P. Garrahan "from the Autonomous City of Buenos Aires, Argentina, who required treatment with intravenous insulin and whose blood glucose was remotely monitored with the InsuMate® platform developed at the National University of La Plata. The patients required insulin infusion rates in doses markedly higher than those of other critically ill patients, who were impressively related to the values of inflammation markers. The infusion could be adjusted with four daily glucose monitors and the metrics obtained with the glucose monitor. The use of the continuous remote glucose monitoring system made it possible to decrease the frequency of glycemic monitoring during treatment.


Assuntos
COVID-19 , Pediatria , Glucose , Hiperglicemia , Insulina
11.
Cancers (Basel) ; 13(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063829

RESUMO

BACKGROUND: The human gut harbors around 1013-1014 microorganisms, collectively referred to as gut microbiota. Recent studies have found that the gut microbiota may have an impact on the interaction between immune regulation and anti-cancer immunotherapies. METHODS: In order to characterize the diversity and composition of commensal microbiota and its relationship with response to immune checkpoint blockade (ICB), 16S ribosomal DNA (rDNA) sequencing was performed on 69 stool samples from advanced non-small cell lung cancer (NSCLC) patients prior to treatment with ICB. RESULTS: The use of antibiotics and ICB-related skin toxicity were significantly associated with reduced gut microbiota diversity. However, antibiotics (ATB) usage was not related to low ICB efficacy. Phascolarctobacterium was enriched in patients with clinical benefit and correlated with prolonged progression-free survival, whereas Dialister was more represented in patients with progressive disease, and its higher relative abundance was associated with reduced progression-free survival and overall survival, with independent prognostic value in multivariate analysis. CONCLUSIONS: Our results corroborate the relation between the baseline gut microbiota composition and ICB clinical outcomes in advanced NSCLC patients, and provide novel potential predictive and prognostic biomarkers for immunotherapy in NSCLC.

13.
Artigo em Inglês | MEDLINE | ID: mdl-33782005

RESUMO

Molecular surveillance by whole-genome sequencing was used to monitor the susceptibility of circulating influenza A viruses to three polymerase complex inhibitors. A total of 12 resistance substitutions were found among 285 genomes analyzed, but none were associated with high levels of resistance. Natural resistance to these influenza A antivirals is currently uncommon.


Assuntos
Vírus da Influenza A , Influenza Humana , Antivirais/farmacologia , Antivirais/uso terapêutico , Farmacorresistência Viral/genética , Humanos , Vírus da Influenza A/genética , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Espanha/epidemiologia
14.
PLoS One ; 16(2): e0246962, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33577575

RESUMO

Metabolic pathway comparison and interaction between different species can detect important information for drug engineering and medical science. In the literature, proposals for reconstructing and comparing metabolic networks present two main problems: network reconstruction requires usually human intervention to integrate information from different sources and, in metabolic comparison, the size of the networks leads to a challenging computational problem. We propose to automatically reconstruct a metabolic network on the basis of KEGG database information. Our proposal relies on a two-level representation of the huge metabolic network: the first level is graph-based and depicts pathways as nodes and relations between pathways as edges; the second level represents each metabolic pathway in terms of its reactions content. The two-level representation complies with the KEGG database, which decomposes the metabolism of all the different organisms into "reference" pathways in a standardised way. On the basis of this two-level representation, we introduce some similarity measures for both levels. They allow for both a local comparison, pathway by pathway, and a global comparison of the entire metabolism. We developed a tool, MetNet, that implements the proposed methodology. MetNet makes it possible to automatically reconstruct the metabolic network of two organisms selected in KEGG and to compare their two networks both quantitatively and visually. We validate our methodology by presenting some experiments performed with MetNet.


Assuntos
Redes e Vias Metabólicas , Metabolômica/métodos , Animais , Análise por Conglomerados , Humanos , Software , Simbiose
16.
Biology (Basel) ; 10(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374107

RESUMO

Defining the essential gene components for a system to be considered alive is a crucial step toward the synthesis of artificial life. Fifteen years ago, Gil and coworkers proposed the core of a putative minimal bacterial genome, which would provide the capability to achieve metabolic homeostasis, reproduce, and evolve to a bacterium in an ideally controlled environment. They also proposed a simplified metabolic chart capable of providing energy and basic components for a minimal living cell. For this work, we have identified the components of the minimal metabolic network based on the aforementioned studies, associated them to the KEGG database and, by applying the MetaDAG methodology, determined its Metabolic Building Blocks (MBB) and reconstructed its metabolic Directed Acyclic Graph (m-DAG). The reaction graph of this metabolic network consists of 80 compounds and 98 reactions, while its m-DAG has 36 MBBs. Additionally, we identified 12 essential reactions in the m-DAG that are critical for maintaining the connectivity of this network. In a similar manner, we reconstructed the m-DAG of JCVI-syn3.0, which is an artificially designed and manufactured viable cell whose genome arose by minimizing the one from Mycoplasma mycoides JCVI-syn1.0, and of "Candidatus Nasuia deltocephalinicola", the bacteria with the smallest natural genome known to date. The comparison of the m-DAGs derived from a theoretical, an artificial, and a natural genome denote slightly different lifestyles, with a consistent core metabolism. The MetaDAG methodology we employ uses homogeneous descriptors and identifiers from the KEGG database, so that comparisons between bacterial strains are not only easy but also suitable for many research fields. The modeling of m-DAGs based on minimal metabolisms can be the first step for the synthesis and manipulation of minimal cells.

17.
Database (Oxford) ; 20202020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32055857

RESUMO

The Symbiotic Genomes Database (SymGenDB; http://symbiogenomesdb.uv.es/) is a public resource of manually curated associations between organisms involved in symbiotic relationships, maintaining a catalog of completely sequenced/finished bacterial genomes exclusively. It originally consisted of three modules where users could search for the bacteria involved in a specific symbiotic relationship, their genomes and their genes (including their orthologs). In this update, we present an additional module that includes a representation of the metabolic network of each organism included in the database, as Directed Acyclic Graphs (MetaDAGs). This module provides unique opportunities to explore the metabolism of each individual organism and/or to evaluate the shared and joint metabolic capabilities of the organisms of the same genera included in our listing, allowing users to construct predictive analyses of metabolic associations and complementation between systems. We also report a ~25% increase in manually curated content in the database, i.e. bacterial genomes and their associations, with a final count of 2328 bacterial genomes associated to 498 hosts. We describe new querying possibilities for all the modules, as well as new display features for the MetaDAGs module, providing a relevant range of content and utility. This update continues to improve SymGenDB and can help elucidate the mechanisms by which organisms depend on each other.


Assuntos
Bases de Dados Genéticas , Genômica , Metadados , Simbiose/genética , Genoma Bacteriano/genética , Redes e Vias Metabólicas/genética
18.
Environ Entomol ; 47(2): 325-333, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29506121

RESUMO

Aphids (Hemiptera: Aphididae) can harbor two types of bacterial symbionts. In addition to the obligate endosymbiont Buchnera aphidicola Munson, Baumann and Kinsey 1991 (Enterobacteriales: Enterobacteriaceae), several facultative symbiotic bacteria, called secondary (S) symbionts, have been identified among many important pest aphid species. To determine interpopulational diversity of S-symbionts, we carried out a survey in a total of 18 populations of six aphid species collected from six localities in Tunisia, by performing a diagnostic polymerase chain reaction analysis of partial 16S-23S rRNA operon sequences. While 61.7% of individuals contained only Buchnera, three S-symbionts were found at different frequencies. Arsenophonus sp. Gherna et al. 1991 (Enterobacteriales: Enterobacteriaceae) was found in all species under study except for Acyrtosiphon pisum (Harris 1776) (Aphidinae: Macrosiphini); Serratia symbiotica Moran et al. 2005 (Enterobacteriales: Enterobacteriaceae) was present in all analyzed individuals of A. pisum but only sporadically in Aphis spiraecola (Patch 1914) (Aphidinae: Aphidini) and Hyalopterus amygdali (Blanchard 1840) (Aphidinae: Aphidini), while Hamiltonella defensa Moran et al. 2005 (Enterobacteriales: Enterobacteriaceae) was found in all analyzed individuals of one population of Aphis gossypii (Glover 1877) (Aphidinae: Aphidini) and sporadically in two populations of Hyalopterus. The lysogenic bacteriophage APSE-1 (A. pisum secondary endosymbiont, type 1) was detected in the three populations infected with H. defensa. This bacteriophage has been associated with moderate protection against braconid parasitoids in pea aphids. The high prevalence of Arsenophonus sp. in our samples is in accordance with previous studies indicating that, among gammaproteobacteria, this genus is one of the most widespread insect facultative symbionts.


Assuntos
Afídeos/microbiologia , RNA Ribossômico 16S/genética , Simbiose , Animais , Filogenia , Tunísia
19.
PeerJ ; 5: e3162, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28439458

RESUMO

We report the genome sequence of Exiguobacterium chiriqhucha str. N139, isolated from a high-altitude Andean lake. Comparative genomic analyses of the Exiguobacterium genomes available suggest that our strain belongs to the same species as the previously reported E. pavilionensis str. RW-2 and Exiguobacterium str. GIC 31. We describe this species and propose the chiriqhucha name to group them. 'Chiri qhucha' in Quechua means 'cold lake', which is a common origin of these three cosmopolitan Exiguobacteria. The 2,952,588-bp E. chiriqhucha str. N139 genome contains one chromosome and three megaplasmids. The genome analysis of the Andean strain suggests the presence of enzymes that confer E. chiriqhucha str. N139 the ability to grow under multiple environmental extreme conditions, including high concentrations of different metals, high ultraviolet B radiation, scavenging for phosphorous and coping with high salinity. Moreover, the regulation of its tryptophan biosynthesis suggests that novel pathways remain to be discovered, and that these pathways might be fundamental in the amino acid metabolism of the microbial community from Laguna Negra, Argentina.

20.
Meat Sci ; 122: 16-24, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27468139

RESUMO

The aims of this work were to identify moulds responsible for black spot spoilage in the drying and cellar stages of dry-cured ham processing and evaluate the effectiveness of preventive actions for controlling this alteration. Four mould strains isolated from spoiled hams were identified by morphological characteristics and the ITS and ß-tubulin sequencing. Two of them were Cladosporium oxysporum, one was C. cladosporioides and the remaining one was C. herbarum. These spoiling strains reproduced the black spots on dry-cured ham-based media and ham slices. Additionally, the effect of water activity (aw) conditions reached throughout dry-cured ham ripening and the activity of the protective culture Penicillium chrysogenum CECT 20922 against the spoiling moulds were evaluated. In the dry-cured ham model system the growth of the Cladosporium strains was minimised when the aw approaches 0.84 or in P. chrysogenum CECT 20922 inoculated dry-cured ham slices. Therefore such combination could be used to avoid the black spot formation in dry-cured ham.


Assuntos
Cladosporium/crescimento & desenvolvimento , Cladosporium/isolamento & purificação , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Produtos da Carne/microbiologia , Penicillium chrysogenum/fisiologia , Animais , Dessecação/métodos , Interações Microbianas , Sus scrofa
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