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Sfela is a white brined Greek cheese of protected designation of origin (PDO) produced in the Peloponnese region from ovine, caprine milk, or a mixture of the two. Despite the PDO status of Sfela, very few studies have addressed its properties, including its microbiology. For this reason, we decided to investigate the microbiome of two PDO industrial Sfela cheese samples along with two non-PDO variants, namely Sfela touloumotiri and Xerosfeli. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), 16S rDNA amplicon sequencing and shotgun metagenomics analysis were used to identify the microbiome of these traditional cheeses. Cultured-based analysis showed that the most frequent species that could be isolated from Sfela cheese were Enterococcus faecium, Lactiplantibacillus plantarum, Levilactobacillus brevis, Pediococcus pentosaceus and Streptococcus thermophilus. Shotgun analysis suggested that in industrial Sfela 1, Str. thermophilus dominated, while industrial Sfela 2 contained high levels of Lactococcus lactis. The two artisanal samples, Sfela touloumotiri and Xerosfeli, were dominated by Tetragenococcus halophilus and Str. thermophilus, respectively. Debaryomyces hansenii was the only yeast species with abundance > 1% present exclusively in the Sfela touloumotiri sample. Identifying additional yeast species in the shotgun data was challenging, possibly due to their low abundance. Sfela cheese appears to contain a rather complex microbial ecosystem and thus needs to be further studied and understood. This might be crucial for improving and standardizing both its production and safety measures.
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The Notch signaling pathway is the most crucial link in the normal operation and maintenance of physiological functions of mammalian life processes. Notch receptors interact with ligands and this leads to three cleavages and goes on to enter the nucleus to initiate the transcription of target genes. The Notch signaling pathway deeply participates in the differentiation and function of various cells, including immune cells. Recent studies indicate that the outcomes of Notch signaling are changeable and highly dependent on different bacterial infection. The Notch signaling pathway plays a different role in promoting and inhibiting bacterial infection. In this review, we focus on the latest research findings of the Notch signaling pathway in bacterial infectious diseases. The Notch signaling pathway is critically involved in a variety of development processes of immunosuppression of different APCs. The Notch signaling pathway leads to functional changes in epithelial cells to aggravate tissue damage. Specifically, we illustrate the regulatory mechanism of the Notch signaling pathway in various bacterial infections, such as Mycobacterium tuberculosis, Mycobacterium avium paratuberculosis, Mycobacterium leprae, Helicobacter pylori, Klebsiella pneumoniae, Bacillus subtilis, Staphylococcus aureus, Ehrlichia chaffeensis and sepsis. Collectively, this review will not only help beginners intuitively and systematically understand the Notch signaling pathway in bacterial infectious diseases but also help experts to generate fresh insight in this field.
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Infecciones Bacterianas , Enfermedades Transmisibles , Mycobacterium tuberculosis , Animales , Humanos , Transducción de Señal , Receptores Notch/metabolismo , Mycobacterium tuberculosis/metabolismo , Mamíferos/metabolismoRESUMEN
Consumers today seek safe functional foods with proven health-promoting properties. Current evidence shows that a healthy diet can effectively alleviate oxidative stress levels and reduce inflammatory markers, thereby preventing the occurrence of many types of cancer, hypertension, and cardiovascular and neurological pathologies. Nevertheless, as fruits and vegetables are mainly consumed fresh, they can serve as vectors for the transmission of pathogenic microorganisms associated with various disease outbreaks. As a result, there has been a surge in interest in the microbiome of fruits and vegetables. Therefore, given the growing interest in sweet cherries, and since their microbial communities have been largely ignored, the primary purpose of this study is to investigate their culturome at various maturity stages for the first time. A total of 55 microorganisms were isolated from sweet cherry fruit, comprising 23 bacteria and 32 fungi species. Subsequently, the selected isolates were molecularly identified by amplifying the 16S rRNA gene and ITS region. Furthermore, it was observed that the communities became more diverse as the fruit matured. The most abundant taxa included Pseudomonas and Ralstonia among the bacteria, and Metschnikowia, Aureobasidium, and Hanseniaspora among the fungi.
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Microbiota consisting of various fungi and bacteria have a significant impact on the physiological functions of the host. However, it is unclear which species are essential to this impact and how they affect the host. This study analyzed and isolated microbes from natural food sources of Drosophila larvae, and investigated their functions. Hanseniaspora uvarum is the predominant yeast responsible for larval growth in the earlier stage of fermentation. As fermentation progresses, Acetobacter orientalis emerges as the key bacterium responsible for larval growth, although yeasts and lactic acid bacteria must coexist along with the bacterium to stabilize this host-bacterial association. By providing nutrients to the larvae in an accessible form, the microbiota contributes to the upregulation of various genes that function in larval cell growth and metabolism. Thus, this study elucidates the key microbial species that support animal growth under microbial transition.
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Drosophila , Levaduras , Animales , Larva , Filogenia , Levaduras/metabolismo , Bacterias/genética , FermentaciónRESUMEN
Microbial (bacteria and fungi) community structures and their distributions in urban household municipal solid waste (HMSW) were characterized in a sampling campaign in 38 cities of China covering 5 climatic zones. All samples were collected from garbage containers in residential communities during the Winter of 2022, from January 11 to 26. A total of 247 bacterial genera belonging to 22 phyla were identified among the samples. Firmicutes (44.3 %), Bacteroidetes (33.77 %) and Proteobacteria (21.54 %) were the top 3 dominant phyla, and Arcicella (33.11 %) and Leuconostoc (21.87 %) were the dominant genera. Meanwhile, 124 fungal genera from 7 fungal phyla were detected. Ascomycota was the most dominant phylum, with an average relative abundance of 77.31 %. Hanseniaspora (24.03 %), Debaryomyces (13.47 %), Candida (12.18) were the top 3 dominant fungal genera. Alpha-diversity analysis showed that the species richness and diversity of bacterial and fungal communities of HMSW samples belonging to different climatic zones did not differ significantly. Nonmetric multidimensional scaling (NMDS) analysis confirmed that climatic had an effect on microbial communities but did not show a significant correlation. In addition, the distribution of microbial community in different samples from the same climate zone varied considerably, suggesting the HMSW source play important role in shaping microbial community composition. Considering that residential HMSW is relatively fresh, we speculates that the original microorganisms residing in different components of HMSW are key influencing factor for the community, while the reshaping force driven by environmental conditions are relatively weak. In addition, the study identified 13 bacterial and 16 fungal pathogens with Pseudomonas putida (0.25 %) and Sclerotinia sclerotiorum (2.12 %) as the most abundant potential pathogenic bacteria and fungi, respectively. These findings provide valuable information for characterizing microbial features and potential risks of HMSW in its management system.
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COVID-19 , Residuos Sólidos , Humanos , Bacterias , China/epidemiología , Brotes de EnfermedadesRESUMEN
The effects of farm management practices and seasonal variation on the microbial community and chemical composition of corn and grass-legume silage are largely understudied due to the advantages of controlled mini-silo experiments. This study aims to investigate the effects that some key farm factors (use of an inoculant, farm region, and bunker or tower silo) and seasonal variations have on corn and grass-legume silage from farms across Ontario, Quebec, and New York. The silage was either treated with a commercial inoculant (Lallemand Biotal Buchneri 500® or Chr Hansen SiloSolve FC®) or left untreated. The bacterial communities of silage were compared to those of raw bulk tank milk from the same farm to determine if they were similarly affected by management practices or seasonal variations. Family level analysis of the 16S rRNA V3-V4 gene amplicon bacterial community, the ITS1 amplicon fungal community, NMR water soluble metabolome, and mycotoxin LC-MS were performed on silage over a two-year period. Chemical compounds associated with the use of inoculants in corn and grass-legume silage were higher in inoculated corn (acetate, propane-1,2-diol, γ-aminobutyrate; p < 0.001) and grass-legume (propionate; p = 0.011). However, there was no significant difference in the relative abundance (RA) of Lactobacillaceae in either silage type. Leuconostocaceae was higher in non-inoculated corn (p < 0.001) and grass-legume (p < 0.001) silage than in inoculated silage. Tower silos had higher RA of Leuconostocaceae (p < 0.001) and higher pH (p < 0.001) in corn and grass-legume silage. The one farm that used liquid manure with no other fertilizer type had higher RA of Clostridiaceae (p = 0.045) and other rumen/fecal (p < 0.006) bacteria in grass-legume silage than all other farms. Seasonal variation affected most of the key silage microbial families, however the trends were rarely visible across both years. Few trends in microbial variation could be observed in both silage and bulk tank milk: two farms had higher Moraxellaceae (p < 0.001) in milk and either corn or grass-legume silage. In farms using an inoculant, lower Staphylococcaceae was observed in the raw bulk tank milk.
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Florida, USA, has witnessed an increased incidence of leprosy cases lacking traditional risk factors. Those trends, in addition to decreasing diagnoses in foreign-born persons, contribute to rising evidence that leprosy has become endemic in the southeastern United States. Travel to Florida should be considered when conducting leprosy contact tracing in any state.
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Lepra , Mycobacterium leprae , Humanos , Animales , Mycobacterium leprae/genética , Florida/epidemiología , Armadillos , Lepra/diagnóstico , Lepra/epidemiología , Sudeste de Estados UnidosRESUMEN
In 2008, bacilli from 2 Hansen disease (leprosy) cases were identified as a new species, Mycobacterium lepromatosis. We conducted a systematic review of studies investigating M. lepromatosis as a cause of HD. Twenty-one case reports described 27 patients with PCR-confirmed M. lepromatosis infection (6 dual M. leprae/M. lepromatosis): 10 case-patients in the United States (7 originally from Mexico), 6 in Mexico, 3 in the Dominican Republic, 2 each in Singapore and Myanmar, and 1 each in Indonesia, Paraguay, Cuba, and Canada. Twelve specimen surveys reported 1,098 PCR-positive findings from 1,428 specimens, including M. lepromatosis in 44.9% (133/296) from Mexico, 3.8% (5/133) in Colombia, 12.5% (10/80) in Brazil, and 0.9% (2/224) from the Asia-Pacific region. Biases toward investigating M. lepromatosis as an agent in cases of diffuse lepromatous leprosy or from Mesoamerica precluded conclusions about clinicopathologic manifestations and geographic distribution. Current multidrug treatments seem effective for this infection.
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Lepra Lepromatosa , Lepra , Mycobacterium , Humanos , Lepra/diagnóstico , Lepra/tratamiento farmacológico , Lepra/epidemiología , Lepra Lepromatosa/diagnóstico , Lepra Lepromatosa/tratamiento farmacológico , Lepra Lepromatosa/epidemiología , Mycobacterium leprae/genéticaRESUMEN
Traditional dry fermented meat products are obtained artisanally in many countries, where they represent a gastronomic heritage well distinguished from industrial counterparts. This food category is most often obtained from red meat, a food commodity that is under attack because of evidence of increased risk of cancer and degenerative diseases with high consumption. However, traditional fermented meat products are intended for moderate consumption and gastronomic experience, and, as such, their production must be continued, which would also help safeguard the culture and economy of the geographical areas of origin. In this review, the main risks attributed to these products are considered, and how these risks are reduced by the application of autochthonous microbial cultures is highlighted by reviewing studies reporting the effects of autochthonous lactic acid bacteria (LAB), coagulase negative staphylococci (CNS), Debaryomyces hansenii and Penicillium nalgiovense on microbiological and chemical safety and on sensory attributes. The role of dry fermented sausages as a source of microorganisms that can be beneficial to the host is also considered. From the results of the studies reviewed here it appears that the development of autochthonous cultures for these foods can ensure safety and stabilize sensory characteristics and has the capacity to be extended to a larger variety of traditional products.
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Bacteria cells exhibit multidrug resistance in one of two ways: by raising the genetic expression of multidrug efflux pumps or by accumulating several drug-resistant components in many genes. Multidrug-resistive tuberculosis bacteria are treated by multidrug therapy, where a few certain antibacterial drugs are administered together to kill a bacterium jointly. A major drawback of conventional multidrug therapy is that the administration never ensures the reaching of different drug molecules to a particular bacterium cell at the same time, which promotes growing drug resistivity step-wise. As a result, it enhances the treatment time. With additional tabletability and plasticity, the formation of a cocrystal of multidrug can ensure administrating the multidrug chemically together to a target bacterium cell. With properly maintaining the basic philosophy of multidrug therapy here, the synergistic effects of drug molecules can ensure killing the bacteria, even before getting the option to raise the drug resistance against them. This can minimize the treatment span, expenditure and drug resistance. A potential threat of epidemic from tuberculosis has appeared after the Covid-19 outbreak. An unwanted loop of finding molecules with the potential to kill tuberculosis, getting their corresponding drug approvals, and abandoning the drug after facing drug resistance can be suppressed here. This perspective aims to develop the universal drug regimen by postulating the principles of drug molecule selection, cocrystallization, and subsequent harmonisation within a short period to address multidrug-resistant bacteria.
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COVID-19 , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Quimioterapia Combinada , Proteínas Bacterianas/metabolismo , Leprostáticos/farmacología , Tuberculosis/tratamiento farmacológico , Bacterias/metabolismo , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiologíaRESUMEN
Making wine via spontaneous fermentation without sulfur dioxide and commercial yeast (spontaneous winemaking) is increasing in recent year, but there is scant research regarding microbial communities present in Japan during spontaneous winemaking using culture-independent molecular methods. We analyzed fungal communities and populations during laboratory-scale spontaneous winemaking using sterilized labware to avoid winery-resident microbes. In the spontaneous fermentation of four grape varieties (Pinot Noir, Riesling, Koshu, and Koshusanjaku) grown in the same Japanese vineyard, our analysis of yeast and other fungal species by next-generation sequencing based on the ITS1 region demonstrated that Saccharomyces cerevisiae was eventually dominant in seven of 12 fermentation batches (three replications for each grape variety), whereas non-Saccharomyces species (e.g., Schizosaccharomyces japonicus, Lachancea dasiensis, and Hanseniaspora valbyensis) became dominant in four batches at the end of fermentation. In another batch, lactic acid bacteria (LAB) became dominant and the fermentation remained incomplete. Diverse microbes were involved in the spontaneous fermentation (particularly in Koshusanjaku), indicating that residual sugar remained and lactic and acetic acid largely increased. Compared to the control wine made with SO2 and commercial yeast, the concentration of lactic acid was 47-fold higher in the must dominated by L. dasiensis, and the concentrations of acetic acid and lactic acid were 10-fold and 20-fold higher in the must dominated by LAB, respectively. Even when indigenous S. cerevisiae became dominant, the finished wines obtained high sensory-analysis scores for complexity but low scores for varietal typicality, indicating the risk of fermentation with unselected wild yeast on the grapes grown in Japan.
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Microbiota , Vitis , Vino , Vino/análisis , Saccharomyces cerevisiae/genética , Fermentación , Japón , Ácido Láctico/análisisRESUMEN
Bacterial cellulose (BC) represents a renewable biomaterial with unique properties promising for biotechnology and biomedicine. Komagataeibacter hansenii ATCC 53,582 is a well-characterized high-yield producer of BC used in the industry. Its genome encodes three distinct cellulose synthases (CS), bcsAB1, bcsAB2, and bcsAB3, which together with genes for accessory proteins are organized in operons of different complexity. The genetic foundation of its high cellulose-producing phenotype was investigated by constructing chromosomal in-frame deletions of the CSs and of two predicted regulatory diguanylate cyclases (DGC), dgcA and dgcB. Proteomic characterization suggested that BcsAB1 was the decisive CS because of its high expression and its exclusive contribution to the formation of microcrystalline cellulose. BcsAB2 showed a lower expression level but contributes significantly to the tensile strength of BC and alters fiber diameter significantly as judged by scanning electron microscopy. Nevertheless, no distinct extracellular polymeric substance (EPS) from this operon was identified after static cultivation. Although transcription of bcsAB3 was observed, expression of the protein was below the detection limit of proteome analysis. Alike BcsAB2, deletion of BcsAB3 resulted in a visible reduction of the cellulose fiber diameter. The high abundance of BcsD and the accessory proteins CmcAx, CcpAx, and BglxA emphasizes their importance for the proper formation of the cellulosic network. Characterization of deletion mutants lacking the DGC genes dgcA and dgcB suggests a new regulatory mechanism of cellulose synthesis and cell motility in K. hansenii ATCC 53,582. Our findings form the basis for rational tailoring of the characteristics of BC. KEY POINTS: ⢠BcsAB1 induces formation of microcrystalline cellulose fibers. ⢠Modifications by BcsAB2 and BcsAB3 alter diameter of cellulose fibers. ⢠Complex regulatory network of DGCs on cellulose pellicle formation and motility.
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Ácido Acético , Acetobacteraceae , Ácido Acético/metabolismo , Matriz Extracelular de Sustancias Poliméricas , Proteómica , Acetobacteraceae/genética , Acetobacteraceae/metabolismo , Celulosa/metabolismoRESUMEN
Bacterial cellulose (BC) is a biopolymer principally synthetized by strains of the genus Komagataeibacter. However, high costs and low production yield make large-scale application difficult. The aim of this work was to evaluate the effects of successive batch culture before fermentation on the ability to increase the capacity of bacterial cellulose biosynthesis by a low-producing strain. The Komagataeibacter hansenii strain ATCC 23,769 was initially cultivated in fermentation broth for two periods of 35 or 56 days under static conditions. At the end of each period of time, they were transferred to new broth to be cultivated again (new batch culture cycle) for 35 or 56 days and carried out in parallel with a 10-day fermentation to determine the quantity of BC produced. As a result, a greater increase was observed after the end of the second and third batch cultures of 56 days (increases of 137% and 187% in relation to the nonbatch cultured strain, respectively). The produced samples presented higher crystallinity and thermal properties but lower water holding capacity. Through this work, it was concluded that the longer the batch culture time was, the greater the increase in the capacity of cellulose biosynthesis, which also depended on the number of successive batch culture cycles carried out.
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Acetobacteraceae , Celulosa , Técnicas de Cultivo Celular por Lotes , Acetobacteraceae/genética , BiopolímerosRESUMEN
Our study investigated the potential of Annona squamosa (L.) fruit as a reservoir of yeasts and lactic acid bacteria having biotechnological implications, and phenolics capable of modifying the ecology of microbial consortia. Only a single species of lactic acid bacteria (Enterococcus faecalis) was identified, while Annona fruit seemed to be a preferred niche for yeasts (Saccharomyces cerevisiae, Hanseniaspora uvarum), which were differentially distributed in the fruit. In order to identify ecological implications for inherent phenolics, the antimicrobial potential of water- and methanol/water-soluble extracts from peel and pulp was studied. Pulp extracts did not show any antimicrobial activity against the microbial indicators, while some Gram-positive bacteria (Staphylococcus aureus, Staphylococcus saprophyticus, Listeria monocytogenes, Bacillus megaterium) were susceptible to peel extracts. Among lactic acid bacteria used as indicators, only Lactococcus lactis and Weissella cibaria were inhibited. The chemical profiling of methanol/water-soluble phenolics from Annona peel reported a full panel of 41 phenolics, mainly procyanidins and catechin derivatives. The antimicrobial activity was associated to specific compounds (procyanidin dimer type B [isomer 1], rutin [isomer 2], catechin diglucopyranoside), in addition to unidentified catechin derivatives. E. faecalis, which was detected in the epiphytic microbiota, was well adapted to the phenolics from the peel. Peel phenolics had a growth-promoting effect toward the autochthonous yeasts S. cerevisiae and H. uvarum.
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Annona , Antiinfecciosos , Catequina , Malus , Frutas/microbiología , Catequina/análisis , Annona/química , Annona/microbiología , Metanol/análisis , Saccharomyces cerevisiae , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antiinfecciosos/farmacología , Antiinfecciosos/análisis , Agua/análisis , Azúcares/análisisRESUMEN
Úlceras crônicas são definidas quando o processo de reparação do tecido excede o período de 3 meses, dificultando sua cicatrização. Sua etiologia pode ser multifatorial, como a ocorrência de traumas e consequência de patologias, como hanseníase, hipertensão e diabetes. As úlceras abrigam diversos microrganismos colonizadores e residentes que podem tornar-se potenciais agravantes a sua condição clínica, visto sua capacidade de formação de biofilmes e resistência antimicrobiana, diminuindo a eficácia da terapêutica. O objetivo deste trabalho foi determinar os agentes microbianos presentes em úlceras de pacientes com doenças crônicas atendidos no ambulatório de feridas do Instituto Lauro de Souza Lima, avaliar a susceptibilidade antimicrobiana destes isolados e sua capacidade de produção de biofilme, bem como comparar os resultados evidenciados por swab e biópsia e correlacionar os resultados microbiológicos com dados clínicos dos pacientes. Foram coletadas amostras de exsudato por swab e biópsia de úlceras crônicas dos participantes com doenças crônicas. As amostras foram semeadas em ágar sangue, manitol, cetrimide e MacCnkey para posterior identificação microbiana. Também foi desempenhada a determinação da susceptibilidade aos antimicrobianos e capacidade de produção de biofilme dos isolados identificados por swab e biópsia. Foram identificados 47 microrganismos no total, sendo 26 (55%) isolados presentes no swab e 21 (45%) em biópsia. P. aeruginosa, P. mirabilis e S. aureus foram as bactérias comumente prevalentes em ambos os materiais de coleta, com predomínio de P. aeruginosa. Apenas 16 (36%) das bactérias demonstraram capacidade de produzir biofilme, com destaque para o grupo dos gram-positivos (92%) que também exibiram alto perfil de susceptibilidade frente linezolida e vancomicina. Meropenem foi o único fármaco a mostrar eficácia frente as cepas de P. aeruginosa presentes, enquanto o grupo das enterobactérias apresentaram menor resposta frente a amoxicilina com ácido clavulânico. Swab e biópsia apresentaram uma concordância geral de 60%, semelhante ao observado por outros estudos. Tais diferenças podem se dar devido à presença de colonizadores. A cobertura de zinco e bota de Unna foi correlacionada à ausência de sinais flogísticos de infecção. Os dados sociodemográficos mostram prevalência de indíviduos com baixa escolaridade e idade acima de 60 anos. O swab é menos invasivo e mais utilizado devido sua facilidade e baixo custo em relação a biópsia; contudo, deve ser considerado com mais cautela na análise dos resultados microbiológicos.
Chronic wounds are defined when the tissue repair process exceeds the period of 3 months, making it difficult to heal. Its etiology can be multifactorial, such as the occurrence of trauma and consequences of pathologies, such as leprosy, hypertension, and diabetes mellitus. Ulcers harbor several colonizing and resident microorganisms that can become potential aggravating factors for their clinical condition, given their ability to form biofilms and their antimicrobial resistance, decreasing the therapeutic efficacy. This study aimed to determine the microbial agents present in ulcers of patients with chronic conditions treated at the wound clinic of the Instituto Lauro de Souza Lima, to evaluate their antimicrobial susceptibility and ability to produce biofilm, as well as to compare the results evidenced by swab and biopsy and correlate the microbiological results with clinical data of the patients. Exudate samples were collected by swab and biopsy of leg ulcers from participants with chronic diseases. Samples were seeded on sheep blood agar, mannitol, cetrimide and MacConkey agar for subsequent microbial identification. The determination of antimicrobial susceptibility and biofilm production capacity of isolates identified by swab and biopsy was also performed. A total of 47 microorganisms were identified, 26 (55%) of which were isolated from the swab and 21 (45%) from the biopsy. P. aeruginosa, P. mirabilis and S. aureus were the commonly prevalent bacteria in both collection materials, with predominance of P. aeruginosa. Only 16 (36%) bacteria demonstrated the ability to produce biofilm, with emphasis on the gram-positive group (92%) that also exhibited a high profile of susceptibility to linezolid and vancomycin. Meropenem was the only drug to show efficacy against the strains of P. aeruginosa present, while the group of enterobacteria showed less response against amoxicillin with clavulanic acid. Swab and biopsy showed an overall agreement of 60%, similar to that observed by other studies. Such differences may occur due to the presence of colonizers. Zinc coating and Unna boot correlated with the absence of phlogistic signs of infection. Sociodemographic data show a prevalence of individuals with low education and aged over 60 years. The swab is less invasive and more used due to its ease and low cost compared to biopsy; however, it should be considered with more caution in the analysis of microbiological results
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Cicatrización de Heridas , Biopelículas , Úlcera de la Pierna/terapia , Heridas y Lesiones , Biopsia , Farmacorresistencia Microbiana , Complicaciones de la Diabetes , Lepra/complicaciones , AntiinfecciososRESUMEN
Biomaterials and biopolymers, such as bacterial cellulose (BC), are becoming increasingly important as sustainable materials with a wide range of potential applications. However, BC industrial production is associated with several difficulties such as low BC production yields and high production costs; therefore, cheap alternative growth media, e.g. apple juice are being studied intensively. The aim of this study is to evaluate BC synthesis under static conditions on apple juice medium (AJM). The optimal concentration of apple juice in unsupplemented AJM for Novacetimonas hansenii MSCL 1646 was shown by its dilution 1:6 with water, which resulted in 0.89 ± 0.01 g/L of dry BC weight after 10 cultivation days. Low BC synthesis can be associated with insufficient N concentration in apple juice; therefore, different organic and inorganic N sources were evaluated in combination with AJM, and beef extract (5 g/L) was found to be the most suitable. Further, AJM optimisation experiment showed the optimal apple juice and beef extract concentrations as 1:2 and 15 g/L respectively, which resulted in 17.27 ± 0.07 g/L of dry BC weight, which is significantly higher than in standard Hestrin-Schramm (HS) medium (4.07 ± 0.02 g/L). Analysis of mechanical and physical properties showed that use of AJM results in changes in BC properties compared with the standard HS medium. Results of the study indicate that apple juice is an effective and cheap C source that in combination with appropriate N source leads to high BC synthesis and makes it suitable for industrial BC production. KEY POINTS: ⢠Low quality apples can be used as raw material for BC production; ⢠Beef extract improves BC synthesis in apple juice medium; ⢠Use of apple juice and beef extract affect mechanical properties of BC.
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Celulosa , Malus , Medios de Cultivo , Jugos de Frutas y Vegetales , Extractos VegetalesRESUMEN
We evaluated programmatic approaches for skin neglected tropical disease (NTD) surveillance and completed a robust estimation of the burden of skin NTDs endemic to West Africa (Buruli ulcer, leprosy, lymphatic filariasis morbidity, and yaws). In Maryland, Liberia, exhaustive case finding by community health workers of 56,285 persons across 92 clusters identified 3,241 suspected cases. A total of 236 skin NTDs (34.0 [95% CI 29.1-38.9]/10,000 persons) were confirmed by midlevel healthcare workers trained using a tailored program. Cases showed a focal and spatially heterogeneous distribution. This community health workerâled approach showed a higher skin NTD burden than prevailing surveillance mechanisms, but also showed high (95.1%) and equitable population coverage. Specialized training and task-shifting of diagnoses to midlevel health workers led to reliable identification of skin NTDs, but reliability of individual diagnoses varied. This multifaceted evaluation of skin NTD surveillance strategies quantifies benefits and limitations of key approaches promoted by the 2030 NTD roadmap of the World Health Organization.
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Úlcera de Buruli , Medicina Tropical , Úlcera de Buruli/epidemiología , Humanos , Liberia/epidemiología , Enfermedades Desatendidas/diagnóstico , Enfermedades Desatendidas/epidemiología , Reproducibilidad de los ResultadosRESUMEN
Leprosy is a granulomatous infection caused by infection with Mycobacterium leprae or M. lepromatosis. We evaluated skin biopsy and slit skin smear samples from 92 leprosy patients in Colombia by quantitative PCR. Five (5.4%) patients tested positive for M. lepromatosis, providing evidence of the presence of this pathogen in Colombia.
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Lepra , Mycobacterium , Colombia/epidemiología , Humanos , Lepra/diagnóstico , Lepra/epidemiología , Lepra/microbiología , Mycobacterium leprae/genéticaRESUMEN
Microbiological, chemical, and sensory analyses were coupled to understand the origins of kombucha organoleptic compounds and their implication in the flavor of the kombucha beverage. By isolating microorganisms from an original kombucha and comparing it to monocultures and cocultures of two yeasts (Brettanomyces bruxellensis and Hanseniaspora valbyensis) and an acetic acid bacterium (Acetobacter indonesiensis), interaction effects were investigated during the two phases of production. 32 volatile compounds identified and quantified by Headspace-Solid Phase-MicroExtraction-Gas Chromatography/Mass Spectrometry (HS-SPME-GC/MS) were classified according to their origin from tea or microorganisms. Many esters were associated to H. valbyensis, while alcohols were associated to both yeasts, acetic acid to A. indonesiensis, and saturated fatty acids to all microorganisms. Concentration of metabolites were dependent on microbial activity, yeast composition, and phase of production. Sensory analysis showed that tea type influenced the olfactive perception, although microbial composition remained the strongest factor. Association of B. bruxellensis and A. indonesiensis induced characteristic apple juice aroma.
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Oxygen plays a key role in kombucha production, since the production of main organic acids, acetic and gluconic acids, is performed through acetic acid bacteria's oxidative metabolism. Oxygen consumption during traditional kombucha production was investigated by comparing kombucha to mono and cocultures in sugared tea of microorganisms isolated from kombucha. Two yeasts, Brettanomyces bruxellensis and Hanseniaspora valbyensis and one acetic acid bacterium Acetobacter indonesiensis were used. Results showed that tea compounds alone were mainly responsible for oxygen depletion during the first 24 h following inoculation. During the first 7 days phase of production in open vessel, the liquid surface was therefore the only access to oxygen for microorganisms, as anaerobic conditions were sustained below this area. During the 5 days second phase of production after bottling, comparison of cultures with different microbial compositions showed that oxygen was efficiently depleted in the head space of the bottles in 3-6 h if the acetic acid bacterium was present. Lower access to oxygen after bottling stimulated ethanol production in B. bruxellensis and H. valbyensis cocultures with or without A. indonesiensis. This study provides insights into the management of oxygen and the roles of the tea and the biofilm during kombucha production.