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1.
PeerJ ; 11: e14511, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36620745

RESUMO

Background: Integrative studies of animals and associated microbial assemblages (i.e., the holobiont) are rapidly changing our perspectives on organismal ecology and evolution. Insular vertebrates provide ideal natural systems to understand patterns of host-gut microbiota coevolution, the resilience and plasticity these microbial communities over temporal and spatial scales, and ultimately their role in the host ecological adaptation. Methods: Here we used the endemic Balearic wall lizard Podarcis lilfordi to dissect the drivers of the microbial diversity within and across host allopatric populations/islets. By focusing on three extensively studied populations/islets of Mallorca (Spain) and fecal sampling from individually identified lizards along two years (both in spring and autumn), we sorted out the effect of islet, sex, life stage, year and season on the microbiota composition. We further related microbiota diversity to host genetics, trophic ecology and expected annual metabolic changes. Results: All the three populations showed a remarkable conservation of the major microbial taxonomic profile, while carrying their unique microbial signature at finer level of taxonomic resolution (Amplicon Sequence Variants (ASVs)). Microbiota distances across populations were compatible with both host genetics (based on microsatellites) and trophic niche distances (based on stable isotopes and fecal content). Within populations, a large proportion of ASVs (30-50%) were recurrently found along the four sampling dates. The microbial diversity was strongly marked by seasonality, with no sex effect and a marginal life stage and annual effect. The microbiota showed seasonal fluctuations along the two sampled years, primarily due to changes in the relative abundances of fermentative bacteria (mostly families Lachnospiraceae and Ruminococcaceae), without any major compositional turnover. Conclusions: These results support a large resilience of the major compositional aspects of the P. lilfordi gut microbiota over the short-term evolutionary divergence of their host allopatric populations (<10,000 years), but also indicate an undergoing process of parallel diversification of the both host and associated gut microbes. Predictable seasonal dynamics in microbiota diversity suggests a role of microbiota plasticity in the lizards' metabolic adaptation to their resource-constrained insular environments. Overall, our study supports the need for longitudinal and integrative studies of host and associated microbes in natural systems.


Assuntos
Microbioma Gastrointestinal , Lagartos , Microbiota , Animais , Microbioma Gastrointestinal/genética , Estações do Ano , Fezes , Lagartos/microbiologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-36621244

RESUMO

INTRODUCTION: We developed a survey to obtain information on the monitoring practices of major systemic antifungals for treatment and prevention of serious fungal infection. METHODS: The survey included questions relating to methodology and practice and was distributed among 137 colleagues of the Study Group of Medical Mycology (GEMICOMED) from July to December 2019. RESULTS: Monitoring was routinely carried out by most respondents, mainly for voriconazole, and was more likely used to determine the efficacy of the dose administered and less for minimizing drug toxicity. Most responders did not follow the strategies of voriconazole dosage based on CYP2C19 genotyping. Monitoring of posaconazole, itraconazole, or other azole metabolites was not carried out or scarcely demanded. Most responders rarely used flucytosine in their clinical practice nor did they monitor it. According to the answers given by some responders, monitoring isavuconazole, amphotericin B, caspofungin and fluconazole exposure would be also interesting in daily clinical practice in selected patient populations. CONCLUSIONS: The survey reveals common practices and attitudes towards antifungal monitoring, sometimes not performed as per best recommendations, offering an opportunity for education and research. Appropriate use of therapeutic drug monitoring may be an objective of antifungal stewardship programmes.


Assuntos
Antifúngicos , Micoses , Humanos , Antifúngicos/uso terapêutico , Voriconazol/uso terapêutico , Itraconazol/uso terapêutico , Micoses/tratamento farmacológico , Micoses/microbiologia , Fluconazol/uso terapêutico
3.
BMC Infect Dis ; 23(1): 8, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609233

RESUMO

BACKGROUND: Fungal empyema is an uncommon disease and is associated with a high mortality rate. Surgical intervention is suggested in stage II and III empyema. However, there were no studies that reported the outcomes of surgery for fungal empyema. METHODS: This study is a retrospective analysis in a single institute. Patients with empyema thoracis who underwent thoracoscopic decortication between January 2012 and December 2021 were included in the study. We separated the patients into a fungal empyema group and a bacterial empyema group according to culture results. We used 1:3 propensity score matching to reduce selection bias. RESULTS: There were 1197 empyema patients who received surgery. Of these, 575 patients showed positive culture results and were enrolled. Twenty-eight patients were allocated to the fungal empyema group, and the other 547 patients were placed in the bacterial empyema group. Fungal empyema showed significantly longer intensive care unit stay (16 days vs. 3 days, p = 0.002), longer median ventilator usage duration (20.5 days vs. 3 days, p = 0.002), longer hospital stay duration (40 days vs. 17.5 days, p < 0.001) and a higher 30-day mortality rate (21.4% vs. 5.9%, p < 0.001). Fungal empyema revealed significantly poorer 1-year survival rate than bacterial empyema before matching (p < 0.001) but without significant difference after matching. CONCLUSIONS: The fungal empyema patients had much worse surgical outcomes than the bacterial empyema patients. Advanced age and high Charlson Comorbidity Index score are independent predictors for poor prognosis. Prompt surgical intervention combined with the use of antifungal agents was the treatment choice for fungal empyema.


Assuntos
Empiema Pleural , Cirurgia Torácica Vídeoassistida , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Cirurgia Torácica Vídeoassistida/efeitos adversos , Empiema Pleural/tratamento farmacológico , Empiema Pleural/cirurgia , Empiema Pleural/microbiologia , Bactérias
4.
Curr Microbiol ; 80(2): 69, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609598

RESUMO

There has been a growing interest in organic farming as a countermeasure to the environmental burden caused by chemical pesticides. We analyzed and compared the fungal diversity of lemon fruits from organic and conventional cultivation by automated rRNA intergenic spacer analysis (ARISA), accompanied by isolation of cultured colonies and metagenomic analysis. Lemon peels were cut out and subjected to the analyses at purchase and after accelerated storage at 28 °C. The organic lemons did not decay even after 14 weeks, while most of the conventional lemons did decay. The fungal colony counts were not significantly different, although the number of fungal species together with the Shannon index, considering the abundance of each species, clearly showed more diversity in organic lemons than in conventional lemons (p = 0.011). Fusarium sp. (putative F. solani) accounted for as much as 90% of the relative abundance in the decayed conventional lemons. Metagenomic analysis also supported the lack of fungal diversity in conventional lemons. These results may suggest that organic cultivation maintains the diversity of native fungal flora in lemon fruit and could contribute to preventing decay during ambient storage.


Assuntos
Citrus , Praguicidas , Frutas/microbiologia , Citrus/microbiologia
5.
Nat Commun ; 14(1): 102, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609656

RESUMO

The cell nucleus is a primary target for intracellular bacterial pathogens to counteract immune responses and hijack host signalling pathways to cause disease. Here we identify two Brucella abortus effectors, NyxA and NyxB, that interfere with host protease SENP3, and this facilitates intracellular replication of the pathogen. The translocated Nyx effectors directly interact with SENP3 via a defined acidic patch (identified from the crystal structure of NyxB), preventing nucleolar localisation of SENP3 at late stages of infection. By sequestering SENP3, the effectors promote cytoplasmic accumulation of nucleolar AAA-ATPase NVL and ribosomal protein L5 (RPL5) in effector-enriched structures in the vicinity of replicating bacteria. The shuttling of ribosomal biogenesis-associated nucleolar proteins is inhibited by SENP3 and requires the autophagy-initiation protein Beclin1 and the SUMO-E3 ligase PIAS3. Our results highlight a nucleomodulatory function of two Brucella effectors and reveal that SENP3 is a crucial regulator of the subcellular localisation of nucleolar proteins during Brucella infection, promoting intracellular replication of the pathogen.


Assuntos
Brucelose , Proteínas Nucleares , Humanos , Proteínas Nucleares/metabolismo , Núcleo Celular/metabolismo , Brucella abortus/metabolismo , Nucléolo Celular/metabolismo , Brucelose/microbiologia , Chaperonas Moleculares/metabolismo , Proteínas Inibidoras de STAT Ativados/metabolismo , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo
6.
Curr Microbiol ; 80(2): 68, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609736

RESUMO

A strictly anaerobic nitrogen-fixing strain, designated SG106T, was isolated from rice field. The 16S rRNA gene sequence analysis showed that strain SG106T was closely related to the type strain of Fundidesulfovibrio magnetotacticus (97.3%). In phylogenetic (based on 16S rRNA gene sequences) and phylogenomic (constructed using a concatenated alignment of 117 conserved bacterial single-copy genes with GTDB-Tk) trees, strain SG106T clustered with members of the genus Fundidesulfovibrio. Strain SG106T grew at 20-40 °C and 0-0.4% (w/v) NaCl. Desulfoviridin was found in the strain SG106T. The genomic DNA G + C content of strain SG106T was 66.0%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain SG106T and the closely related F. magnetotacticus were 78.4% and 21.7%, respectively. Genome analysis showed that strain SG106T encodes genes for nitrogen fixation (nifHDK). Acetylene reduction experiments showed that the nitrogenase activity of strain SG106T could reach 224.7 µmol C2H4 g-1 protein h-1. Based on the above results, strain SG106T represents a novel species of the genus Fundidesulfovibrio, for which the name Fundidesulfovibrio agrisoli sp. nov. is proposed. The type strain is SG106T (= GDMCC 1.3136T = JCM 35588T).


Assuntos
Ácidos Graxos , Oryza , Oryza/microbiologia , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Fosfolipídeos
7.
Curr Microbiol ; 80(2): 70, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609874

RESUMO

Microbes use both organic and inorganic compounds as electron donors, with different electronic potentials, to produce energy required for growth in environments. Conventional studies on the effects of different electron donors on microbial community has been extensively studied with a set cathode potential. However, it remains under-researched how a microbial community response to the different redox potentials in different environments. Here, we incubated a lake sediment in a single-chamber reactor equipped with three working electrodes, i.e., with potentials of - 0.29 V, - 0.05 V versus standard hydrogen electrode and open-circuit, respectively. Results reveal that the structure of bacterial communities was highly similar for all closed-circuit electrodes (- 0.29 V, - 0.05 V), while differing significantly from those on open-circuit electrodes. We also show that specific bacteria were preferentially enriched by different electrode potentials, i.e., Pseudomonas and Rhodobacter preferentially grew on - 0.05 V and - 0.29 V cathode potentials, Azospirillum and Bosea preferentially grew on - 0.05 V; while Ferrovibrio, Hydrogenophaga, Delftia, and Sphingobium preferentially grew on - 0.29 V. In addition, microorganisms selectively enriched on open-circuit electrodes possess higher connectivity and closer relationship than microorganisms selectively enriched on closed-circuit electrode.


Assuntos
Fontes de Energia Bioelétrica , Microbiota , Fontes de Energia Bioelétrica/microbiologia , Bactérias/genética , Eletrodos
8.
J Agric Food Chem ; 71(1): 288-299, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36591973

RESUMO

Ethylicin (ET) was reported to be promising in the control of rice bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo). The detailed mechanism for this process remains unknown. Disclosed here is an in-depth study on the action mode of ET to Xoo. Through plant physiological and biochemical analysis, it was found that ET could inhibit the proliferation of Xoo by increasing the content of defense enzymes and chlorophyll in rice (Oryza sativa ssp. Japonica cv. Nipponbare). Label-free quantitative proteomic analysis showed that ET affected the rice abscisic acid (ABA) signal pathway and made the critical differential calcium-dependent protein kinase 24 (OsCPK24) more active. In addition, the biological function of OsCPK24 as a mediator for rice resistance to Xoo was determined through the anti-Xoo phenotypic test of OsCPK24 transgenic rice and the affinity analysis of the OsCPK24 recombinant protein in vitro and ET. This study revealed the molecular mechanism of ET-induced resistance to Xoo in rice via OsCPK24, which provided a basis for the development of new bactericides based on the OsCPK24 protein.


Assuntos
Oryza , Xanthomonas , Oryza/metabolismo , Proteômica , Ácido Abscísico/metabolismo , Doenças das Plantas/microbiologia
9.
Nature ; 613(7942): 90-95, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36600067

RESUMO

Organic carbon buried in marine sediment serves as a net sink for atmospheric carbon dioxide and a source of oxygen1,2. The rate of organic carbon burial through geologic history is conventionally established by using the mass balance between inorganic and organic carbon, each with distinct carbon isotopic values (δ13C)3,4. This method is complicated by large uncertainties, however, and has not been tested with organic carbon accumulation data5,6. Here we report a 'bottom-up' approach for calculating the rate of organic carbon burial that is independent from mass balance calculations. We use data from 81 globally distributed sites to establish the history of organic carbon burial during the Neogene (roughly 23-3 Ma). Our results show larger spatiotemporal variability of organic carbon burial than previously estimated7-9. Globally, the burial rate is high towards the early Miocene and Pliocene and lowest during the mid-Miocene, with the latter period characterized by the lowest ratio of organic-to-carbonate burial rates. This is in contrast to earlier work that interpreted enriched carbonate 13C values of the mid-Miocene as massive organic carbon burial (that is, the Monterey Hypothesis)10,11. Suppressed organic carbon burial during the warm mid-Miocene is probably related to temperature-dependent bacterial degradation of organic matter12,13, suggesting that the organic carbon cycle acted as positive feedback of past global warming.


Assuntos
Sequestro de Carbono , Sedimentos Geológicos , Oceanos e Mares , Ciclo do Carbono , Carbonatos/análise , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Oxigênio/análise , História Antiga , Bactérias/metabolismo , Temperatura , Aquecimento Global , Retroalimentação
10.
Gut Microbes ; 15(1): 2163838, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656595

RESUMO

Conflicting evidence exists on the association between consumption of non-steroidal anti-inflammatory drugs (NSAIDs) and symptomatic worsening of inflammatory bowel disease (IBD). We hypothesized that the heterogeneous prevalence of pathobionts [e.g., adherent-invasive Escherichia coli (AIEC)], might explain this inconsistent NSAIDs/IBD correlation. Using IL10-/- mice, we found that NSAID aggravated colitis in AIEC-colonized animals. This was accompanied by activation of the NLRP3 inflammasome, Caspase-8, apoptosis, and pyroptosis, features not seen in mice exposed to AIEC or NSAID alone, revealing an AIEC/NSAID synergistic effect. Inhibition of NLRP3 or Caspase-8 activity ameliorated colitis, with reduction in NLRP3 inflammasome activation, cell death markers, activated T-cells and macrophages, improved histology, and increased abundance of Clostridium cluster XIVa species. Our findings provide new insights into how NSAIDs and an opportunistic gut-pathobiont can synergize to worsen IBD symptoms. Targeting the NLRP3 inflammasome or Caspase-8 could be a potential therapeutic strategy in IBD patients with gut inflammation, which is worsened by NSAIDs.


Assuntos
Anti-Inflamatórios não Esteroides , Colite , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Animais , Camundongos , Anti-Inflamatórios não Esteroides/efeitos adversos , Caspase 8/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/microbiologia , Inflamassomos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/microbiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inibidores de Caspase/farmacologia , Escherichia coli/patogenicidade
11.
PLoS One ; 18(1): e0268385, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656908

RESUMO

Downy mildew is caused by Plasmopara viticola, an obligate oomycete plant pathogen, a devasting disease of grapevine. To protect plants from the disease, complex III inhibitors are among the fungicides widely used. They specifically target the mitochondrial cytochrome b (cytb) of the pathogen to block cellular respiration mechanisms. In the French vineyard, P. viticola has developed resistance against a first group of these fungicides, the Quinone outside Inhibitors (QoI), with a single amino acid substitution G143A in its cytb mitochondrial sequence. The use of QoI was limited and another type of fungicide, the Quinone inside Inhibitors, targeting the same gene and highly effective against oomycetes, was used instead. Recently however, less sensitive P. viticola populations were detected after treatments with some inhibitors, in particular ametoctradin and cyazofamid. By isolating single-sporangia P. viticola strains resistant to these fungicides, we characterized new variants in the cytb sequences associated with cyazofamid resistance: a point mutation (L201S) and more strikingly, two insertions (E203-DE-V204, E203-VE-V204). In parallel with the classical tools, pyrosequencing and qPCR, we then benchmarked short and long-reads NGS technologies (Ion Torrent, Illumina, Oxford Nanopore Technologies) to sequence the complete cytb with a view to detecting and assessing the proportion of resistant variants of P. viticola at the scale of a field population. Eighteen populations collected from French vineyard fields in 2020 were analysed: 12 showed a variable proportion of G143A, 11 of E203-DE-V204 and 7 populations of the S34L variant that confers resistance to ametoctradin. Interestingly, the long reads were able to identify variants, including SNPs, with confidence and to detect a small proportion of P. viticola with multiple variants along the same cytb sequence. Overall, NGS appears to be a promising method for assessing fungicide resistance of pathogens linked to cytb modifications at the field population level. This approach could rapidly become a robust decision support tool for resistance management in the future.


Assuntos
Fungicidas Industriais , Oomicetos , Vitis , Citocromos b/genética , Complexo III da Cadeia de Transporte de Elétrons/genética , Fazendas , Fungicidas Industriais/farmacologia , Oomicetos/genética , Doenças das Plantas/microbiologia , Estrobilurinas/farmacologia , Vitis/microbiologia
12.
PLoS One ; 18(1): e0279616, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656815

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a form of dementia that strikes elderly people more frequently than it does younger people. The cognitive skills and memory of Alzheimer's sufferers continue to deteriorate over time. Recent studies have shown that patients with AD have greater amounts of inflammatory markers in their bodies, which suggests that inflammation occurs early on in the progression of the disease. There is a possibility that Aß oligomers and fibrils can be recognised by TLRs, in addition to the microglial receptors CD14, CD36, and CD47. When Aß binds to either CD36 or TLR4, it sets off a chain reaction of inflammatory chemokines and cytokines that ultimately results in neurodegeneration. Diabetes and Alzheimer's disease have both been recently related to TLR4. The activation of TLR4 has been connected to a variety of clinical difficulties that are associated with diabetes, in addition to the internal environment of the body and the microenvironment of the brain. TLR4 inhibitors have been shown in clinical investigations to not only lessen the likelihood of getting sick but also to increase the average longevity. RESULT: In this work we used molecular docking and molecular dynamics modelling to investigate the effectiveness of FDA-approved antidiabetic plant derived drugs in combating the TLR4 receptor. Molecular docking experiments were used to make a prediction regarding the most important interactions involving 2-Bromoergocryptine Mesylate. With a binding affinity of -8.26 kcal/mol, it stood out from the other candidates as the one with the greatest potential. To verify the interaction pattern that takes place between 2-Bromoergocryptine Mesylate and the TLR4 receptor, a molecular dynamic simulation was run at a time scale of 150 nanoseconds. Because of this, 2-Bromoergocryptine Mesylate was able to make substantial contact with the active site, which led to increased structural stability during the process of the complex's dynamic development. CONCLUSION: As a result of this, the results of our research may be relevant for future research into the efficacy of 2-bromoergocryptine mesylate as a potential lead treatment for TLR4 receptors in intracranial aneurysm rupture in AD.


Assuntos
Doença de Alzheimer , Bromocriptina , Claviceps , Aneurisma Intracraniano , Receptor 4 Toll-Like , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Bromocriptina/farmacologia , Aneurisma Intracraniano/prevenção & controle , Simulação de Acoplamento Molecular , Receptor 4 Toll-Like/metabolismo , Triticum/microbiologia
13.
Cell Host Microbe ; 31(1): 141-145, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36634619

RESUMO

There is increasing awareness of the many different ways host-microbe interactions relate to cancer initiation and progression. Vaccines designed to drive immune responses against key tumor-promoting mechanisms of oncomicrobes like F. nucleatum may provide novel and effective interventions against colorectal cancer and other diseases.


Assuntos
Neoplasias Colorretais , Infecções por Fusobacterium , Vacinas , Humanos , Fusobacterium nucleatum , Neoplasias Colorretais/microbiologia , Infecções por Fusobacterium/microbiologia
14.
Science ; 379(6629): 272-277, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36656954

RESUMO

Understanding the composition and activation of multicomponent receptor complexes is a challenge in biology. To address this, we developed a synthetic approach based on nanobodies to drive assembly and activation of cell surface receptors and apply the concept by manipulating receptors that govern plant symbiosis with nitrogen-fixing bacteria. We show that the Lotus japonicus Nod factor receptors NFR1 and NFR5 constitute the core receptor complex initiating the cortical root nodule organogenesis program as well as the epidermal program controlling infection. We find that organogenesis signaling is mediated by the intracellular kinase domains whereas infection requires functional ectodomains. Finally, we identify evolutionarily distant barley receptors that activate root nodule organogenesis, which could enable engineering of biological nitrogen-fixation into cereals.


Assuntos
Nódulos Radiculares de Plantas , Simbiose , Simbiose/fisiologia , Nódulos Radiculares de Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas
15.
Molecules ; 28(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36677715

RESUMO

Recently, increasing attention has been focused on developing new products based on goat's milk. Consumers positively perceive fermented goat's milk products as health-promoting due to their nutritional value, digestibility, and potential source of probiotics. This study aimed to evaluate the possibility of using different doses of collagen and collagen hydrolysate in the production of probiotic goat's milk fermented by four monocultures: Lacticaseibacillus casei 431®&nbsp;Lactobacillus acidophilus LA- 5®, Lacticaseibacillus paracasei LP26, and Lacticaseibicillus rhamnosus Lr- 32®. A total of 20 experimental groups were prepared, including control groups (without additives), and due to the added probiotic (Lacticaseibacillus casei, Lactobacillus acidophilus, Lacticaseibacillus paracasei, and Lacticaseibacillus rhamnosus), various collagen doses (1.5% and 3.0%) and collagen types (hydrolysate and bovine collagen). Physicochemical, organoleptic, and microbiological characteristics were evaluated after 1 and 21 days of cold storage. The applied additives increased the acidity of the milk even before fermentation. However, milk with bovine collagen and hydrolysate had a higher pH value after fermentation than control milk. The study showed higher than 8 log cfu g-1 viability of probiotic bacteria in goat's milk products during storage due to the proper pH, high buffering capacity, and rich nutrient content of goat's milk. The best survival rate was shown for the L. casei strain after 21 days in milk with collagen protein hydrolysate. Moreover, collagen in milk fermented by L. rhamnosus decreased syneresis compared to its control counterpart. The addition of collagen, especially the hydrolysate, increased the gel hardness of the fermented milk. The collagen additives used in the milk, both in the form of hydrolysate and bovine collagen, caused a darkening of the color of the milk and increased the intensity of the milky-creamy and sweet taste.


Assuntos
Produtos Fermentados do Leite , Probióticos , Animais , Bovinos , Leite/química , Probióticos/química , Produtos Fermentados do Leite/microbiologia , Lactobacillus acidophilus , Cabras , Fermentação
16.
Molecules ; 28(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36677918

RESUMO

Recently, there has been a growing interest in producing functional foods containing encapsulated probiotic bacteria due to their positive effects on human health. According to their perceived health benefits, probiotics have been incorporated into a range of dairy products, but the current major challenge is to market new, multicomponent probiotic foods and supplements. Nevertheless, only a few products containing encapsulated probiotic cells can be found as non-refrigerated products. In this work, spray drying technology was investigated in order to produce an innovative nutraceutical formulation based on lactic acid bacteria (LAB), and was able to ensure a good storage stability of probiotics (no less than 109 CFU/cps) in non-refrigerated conditions. Probiotic-loaded microparticles from spray drying experiments were produced under different conditions and compared by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and the enumeration of the number of viable cells in order to identify the formulation exhibiting the most promising characteristics. Results from the dissolution test revealed that the optimized formulation provides a suitable amount of living cells after digestion of microparticles stored for 12 months at room temperature and confirmed that the microencapsulation process by spray drying ensures a good protection of probiotics for nutraceutical purposes.


Assuntos
Probióticos , Secagem por Atomização , Humanos , Viabilidade Microbiana , Bactérias , Laticínios/microbiologia
17.
Sci Rep ; 13(1): 140, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599842

RESUMO

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) caused by carbapenem-resistant Acinetobacter baumannii (CRAB) are both associated with significant morbidity and mortality in daily clinical practice, as well as in a critical care setting. It is unclear whether colistin susceptible-only Acinetobacter baumannii (CSO AB) is a unique phenotype separate from or a subset of CRAB-associated pneumonia. The aim of this study is to investigate the prevalence of CSO AB pneumonia and compare the presentation and outcome between CSO AB and CRAB-associated pneumonia in critically ill patients. This multicenter retrospective cohort study initially recruited 955 patients with CR-GNB pneumonia. After exclusion, 575 patients left who were ICU-admitted and had CRAB nosocomial pneumonia remained. Among them, 79 patients had CSO AB pneumonia, classified as the CSO AB group. The other 496 patients were classified as the CRAB group. We compared demographic characteristics, disease severity, and treatment outcomes between the two groups. The prevalence of CSO AB among all cases of CRAB pneumonia was 13.74% (79/575). The CSO AB and CRAB groups had similar demographic characteristics and disease severities at initial presentation. The in-hospital mortality rate was 45.6% and 46.4% for CSO AB and CRAB groups, respectively (p = 0.991). The CSO AB group had significantly better clinical outcomes at day 7 (65.8% vs 52.4%, p = 0.036) but longer length of ICU stay (27 days vs 19 days, p = 0.043) compared to the CRAB group. However, other treatment outcomes, including clinical outcomes at day 14 and 28, mortality, microbiological eradication, ventilator weaning, and newly onset dialysis, were similar. In conclusion, CSO AB accounted for 13.74% of all cases of CRAB pneumonia, and the clinical presentation and treatment outcomes of CSO AB and CRAB pneumonia were similar.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Pneumonia Associada à Ventilação Mecânica , Humanos , Colistina/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Acinetobacter baumannii/genética , Carbapenêmicos/uso terapêutico , Estudos Retrospectivos , Prevalência , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Diálise Renal , Suscetibilidade a Doenças , Pneumonia Associada à Ventilação Mecânica/tratamento farmacológico , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Pneumonia Associada à Ventilação Mecânica/microbiologia , Unidades de Terapia Intensiva
18.
Arch Microbiol ; 205(1): 52, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36600085

RESUMO

This study aimed to investigate the biomass production of Bacillus subtilis in flask and bioreactor conditions. It is necessary to carry the culture from the shake flask to the pH, air, temperature and stirring controlled bioreactor in order to reduce the working time and increase the production efficiency and product quality. In this study, Bacillus was isolated from soil and grown under flask and bioreactor conditions as biocontrol agent against Botrytis cinerea and Fusarium oxysporum. In this process, a pH value of 7.5, 100% O2 saturation, 30% dissolved O2, at the temperature of 37 °C, total flow of 0.1 Lmin-1 and mixing speed of 150 min-1 were preferred for optimal concerning high production yield of B. subtilis in bioreactor. To test whether B. subtilis has antifungal activity on the growth of B. cinerea and F. oxysporum, a dual culture assay in a PDA medium was carried out. Ultimately, high biomass production in a short incubation period by reaching 2.2 µg/mL after 9 h in the bioreactor. It was observed that the bacteria produced in the bioreactor cultivation grew stronger and showed high antifungal activity which resulted 33.33% inhibition percentage against B. cinerea. It was concluded that B. subtilis can be used as a green-fungicide against B. cinerea and F. oxysporum, and bacterial metabolites from B. subtilis could pave the way for the development of next generation green/biopesticides.


Assuntos
Bacillus subtilis , Bacillus , Bacillus subtilis/metabolismo , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Reatores Biológicos , Doenças das Plantas/microbiologia
19.
Curr Microbiol ; 80(2): 64, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36600152

RESUMO

A thermophilic cellulase-producing bacterium, Bacillus velezensis strain MRC 5958, from Bakra natural hot Springs, India was characterized through genome sequencing. It has a genome size of 4,467,129 bp and a GC content of 45.7%. A cellulase purified from its fermentation broth has a molecular weight of about 18 kDa. The optimum temperature and pH for carboxymethyl cellulase activity were at 55 °C and pH ~ 7.0. The enzyme is stable over a wide range of temperatures from 30 °C to 70 °C with maximum activity observed at 48 h of incubation. The strain produces cellulase on alkali-treated sugarcane bagasse, rice straw, rice husk, rice bran, and sawdust. The sugarcane bagasse exhibited the most effective carbon source for cellulase production at (85 U/ml) followed by rice bran (68 U/ml), rice husk (60 U/ml), rice straw (48 U/ml), and sawdust (39 U/ml). Therefore, this strain can be a potential thermostable cellulase-producing candidate for converting the waste biomass into biofuel and other industrial enzymes.


Assuntos
Celulase , Fontes Termais , Saccharum , Celulose , Fontes Termais/microbiologia , Celulase/química , Temperatura
20.
Commun Biol ; 6(1): 72, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653523

RESUMO

Sedimentary DNA-based studies revealed the effects of human activity on lake cyanobacteria communities over the last centuries, yet we continue to lack information over longer timescales. Here, we apply high-resolution molecular analyses on sedimentary ancient DNA to reconstruct the history of cyanobacteria throughout the Holocene in a lake in north-eastern Germany. We find a substantial increase in cyanobacteria abundance coinciding with deforestation during the early Bronze Age around 4000 years ago, suggesting increased nutrient supply to the lake by local communities settling on the lakeshore. The next substantial human-driven increase in cyanobacteria abundance occurred only about a century ago due to intensified agricultural fertilisation which caused the dominance of potentially toxic taxa (e.g., Aphanizomenon). Our study provides evidence that humans began to locally impact lake ecology much earlier than previously assumed. Consequently, managing aquatic systems today requires awareness of the legacy of human influence dating back potentially several millennia.


Assuntos
Cianobactérias , DNA Antigo , Humanos , Lagos/microbiologia , Efeitos Antropogênicos , Cianobactérias/genética , Ecologia
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