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A description of new antimicrobial agents suitable for food industries has become necessary, and natural compounds are being considered as promising sources of new active derivatives to be used with the aim of improving food safety. We have previously described desirable antimicrobial and antibiofilm activities against foodborne bacteria by analogs to A-type proanthocyanidins (PACs) with a nitro (NO2) group at carbon 6 of the A-ring. We report herein the synthesis of eight additional analogs with chloro and bromo atoms at the A-ring and the systematic study of their antimicrobial and antioxidant activities in order to evaluate their possible application as biocides or food preservatives, as well as to elucidate new structure-activity relationships. The results from this study show that halogenated analogs to natural A-type proanthocyanidins rise above the nitro derivatives previously reported in their antimicrobial activities. Gram-positive bacteria are the most sensitive to all the analogs and combinations assayed, showing MICs from 10 to 50 µg/mL in most cases, as well as reductions in biofilm formation and the disruption of preformed biofilms of at least 75%. Some structure-activity relationships previously described have also been corroborated. Analogs with just one OH group at the B-ring show better antimicrobial activities than those with two OH groups, and those analogs with two or three OH groups in the whole structure are more active than those with four OH groups. In addition, the analogs with two OH groups at the B-ring and chloro at the A-ring are the most effective when antibiofilm activities are studied, especially at low concentrations.
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Anti-Infecciosos , Antioxidantes , Biofilmes , Indústria Alimentícia , Halogenação , Testes de Sensibilidade Microbiana , Proantocianidinas , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/síntese química , Proantocianidinas/farmacologia , Proantocianidinas/química , Proantocianidinas/síntese química , Biofilmes/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Relação Estrutura-Atividade , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Bactérias Gram-Positivas/efeitos dos fármacosRESUMO
The heterogenicity of antimicrobial resistance genes described in clinically significant bacterial isolates and their potential role in reducing the efficacy of classically effective antibiotics pose a major challenge for global healthcare, especially in infections caused by Gram-negative bacteria. We analyzed 112 multidrug-resistant (MDR) isolates from clinical samples in order to detect high resistance profiles, both phenotypically and genotypically, among four Gram-negative genera (Acinetobacter, Escherichia, Klebsiella, and Pseudomonas). We found that 9.8% of the total selected isolates were classified as extensively drug-resistant (XDR) (six isolates identified as A. baumannii and five among P. pneumoniae isolates). All other isolates were classified as MDR. Almost 100% of the isolates showed positive results for blaOXA-23 and blaNDM-1 genes among the A. baumannii samples, one resistance gene (blaCTX-M) among E. coli, and two genetic determinants (blaCTX-M and aac(6')-Ib) among Klebsiella. In contrast, P. aeruginosa showed just one high-frequency antibiotic resistance gene (dfrA), which was present in 68.42% of the isolates studied. We also describe positive associations between ampicillin and cefotaxime resistance in A. baumannii and the presence of blaVEB and blaGES genes, as well as between the aztreonam resistance phenotype and the presence of blaGES gene in E. coli. These data may be useful in achieving a better control of infection strategies and antibiotic management in clinical scenarios where these multidrug-resistant Gram-negative pathogens cause higher morbidity and mortality.
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Introduction: Previously we have reported a r16S gene next generation sequencing study on the effect of high fat diets in the intestinal microbiota using a murine model. However, many important microbial traits occur at strain level and, in order to detect these population changes, culture-dependent approaches need to be applied. With this goal, we decided to study a very well-known commensal genus, Enterococcus, and therefore, intestinal enterococci methodically isolated during the above-mentioned experiment were analyzed. Materials and methods: A collection of 75 distinct enterococcal strains isolated from feces of mice fed a standard diet or high-fat diets enriched with butter, refined olive oil, or extra virgin olive oil and after 0, 6 or 12 weeks of diet, were genetically and phenotypically characterized in search of virulence factors, biogenic amine production and antibiotic resistance. All strains were tested for the susceptibility in vitro to two virgin olive oil polyphenols, oleuropein (the bitter principle of olives) and hydroxytyrosol (derived from oleuropein by enzymatic hydrolysis and responsible for the high stability of olive oil). Results: No drastic polyphenol effect was found except at high concentrations. However, when carrying out a comparative statistical study in the 75 strains of the collection according to the different diets, we have detected significant differences between the strains isolated from mice fed with a diet enriched with virgin olive oil and the rest of the diets. EVOO strains also presented less resistance to antibiotics and a more beneficial profile overall. Discussion: These results support the prebiotic role of polyphenols, showing how they are able to modulate the set of strains that comprises a genus in the gut, allowing them to adapt to a changing environment in the host's intestine and possibly exerting effects on its physiology.
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Purpose: Frailty is a reversible multidimensional syndrome that puts older people at a high risk of adverse health outcomes. It has been proposed to emerge from the dysregulation of the complex system dynamics of physiologic control systems. We propose the analysis of the fractal complexity of hand movements as a new method to detect frailty in older adults. Methods: FRAIL scale and Fried's phenotype scores were calculated for 1209 subjects-72.4 (5.2) y.o. 569 women-and 1279 subjects-72.6 (5.3) y.o. 604 women-in the pubicly available NHANES 2011-2014 data set, respectively. The fractal complexity of their hand movements was assessed with a detrended fluctuation analysis (DFA) of their accelerometry records and a logistic regression model for frailty detection was fit. Results: Goodness-of-fit to a power law was excellent (R2>0.98). The association between complexity loss and frailty level was significant, Kruskal-Wallis test (df = 2, Chisq = 27.545, p-value <0.001). The AUC of the logistic classifier was moderate (AUC with complexity = 0.69 vs. AUC without complexity = 0.67). Conclusion: Frailty can be characterized in this data set with the Fried phenotype. Non-dominant hand movements in free-living conditions are fractal processes regardless of age or frailty level and its complexity can be quantified with the exponent of a power law. Higher levels of complexity loss are associated with higher levels of frailty. This association is not strong enough to justify the use of complexity loss after adjusting for sex, age, and multimorbidity.
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Developing new types of effective antimicrobial compounds derived from natural products is of interest for the food industry. Some analogs to A-type proanthocyanidins have shown promising antimicrobial and antibiofilm activities against foodborne bacteria. We report herein the synthesis of seven additional analogs with NO2 group at A-ring and their abilities for inhibiting the growth and the biofilm formation by twenty-one foodborne bacteria. Among them, analog 4 (one OH at B-ring; two OHs at D-ring) showed the highest antimicrobial activity. The best results with these new analogs were obtained in terms of their antibiofilm activities: analog 1 (two OHs at B-ring; one OH at D-ring) inhibited at least 75% of biofilm formation by six strains at all of the concentrations tested, analog 2 (two OHs at B-ring; two OHs at D-ring; one CH3 at C-ring) also showed antibiofilm activity on thirteen of the bacteria tested, and analog 5 (one OH at B-ring; one OH at D-ring) was able to disrupt preformed biofilms in eleven strains. The description of new and more active analogs of natural compounds and the elucidation of their structure-activity relationships may contribute to the active development of new food packaging for preventing biofilm formation and lengthening the food shelf life.
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Anti-Infecciosos , Produtos Biológicos , Proantocianidinas , Antibacterianos/farmacologia , Proantocianidinas/farmacologia , Produtos Biológicos/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes , Bactérias , Testes de Sensibilidade MicrobianaRESUMO
Extra virgin olive oil (EVOO) has proven to yield a better health outcome than other saturated fats widely used in the Western diet, including a distinct dysbiosis-preventive modulation of gut microbiota. Besides its high content in unsaturated fatty acids, EVOO also has an unsaponifiable polyphenol-enriched fraction that is lost when undergoing a depurative process that gives place to refined olive oil (ROO). Comparing the effects of both oils on the intestinal microbiota of mice can help us determine which benefits of EVOO are due to the unsaturated fatty acids, which remain the same in both, and which benefits are a consequence of its minority compounds, mainly polyphenols. In this work, we study these variations after only six weeks of diet, when physiological changes are not appreciated yet but intestinal microbial alterations can already be detected. Some of these bacterial deviations correlate in multiple regression models with ulterior physiological values, at twelve weeks of diet, including systolic blood pressure. Comparison between the EVOO and ROO diets reveals that some of these correlations can be explained by the type of fat that is present in the diet, while in other cases, such as the genus Desulfovibrio, can be better understood if the antimicrobial role of the virgin olive oil polyphenols is considered.
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Microbioma Gastrointestinal , Síndrome Metabólica , Camundongos , Animais , Azeite de Oliva , Manteiga , Dieta , PolifenóisRESUMO
Butter and virgin olive oil (EVOO) are two fats differing in their degree of saturation and insaponifiable fraction. EVOO, enriched in polyphenols and other minority components, exerts a distinct effect on health. Using next generation sequencing, we have studied early and long-term effects of both types of fats on the intestinal microbiota of mice, finding significant differences between the two diets in the percentage of certain bacterial taxa, correlating with hormonal, physiological and metabolic parameters in the host. These correlations are not only concomitant, but most noticeably some of the changes detected in the microbial percentages at six weeks are correlating with changes in physiological values detected later, at twelve weeks. Desulfovibrionaceae/Desulfovibrio/D. sulfuricans stand out by presenting at six weeks a statistically significant higher percentage in the butter-fed mice with respect to the EVOO group, correlating with systolic blood pressure, food intake, water intake and insulin at twelve weeks. This not only suggests an early implication in the probability of developing altered physiological and biochemical responses later on in the host lifespan, but also opens the possibility of using this genus as a marker in the risk of suffering different pathologies in the future.
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Microbioma Gastrointestinal , Síndrome Metabólica , Animais , Biomarcadores , Manteiga , Dieta Hiperlipídica , Camundongos , Azeite de Oliva/farmacologiaRESUMO
On March 11, 2020, the World Health Organization declared COVID-19-the infectious disease caused by SARS-CoV-2-a pandemic. Since then, the majority of countries-including Spain-have imposed strict restrictions in order to stop the spread of the virus and the collapse of the health systems. People's health care-seeking behavior has exhibited a change, not only in those months when the COVID-19 control measures were strictest, but also in the months that followed. We aimed to examine how the trends in ophthalmological emergencies changed during the COVID-19 pandemic in one of the largest tertiary referral hospitals in Spain. To this end, data from all the patients that attended the ophthalmological emergency department during the pandemic period-March 2020 to February 2021-were retrospectively collected and compared with data from the previous year. Moreover, a comparison between April 2020-when the restrictions were most severe-and April 2019 was made. A total of 90,694 patients were included. As expected, there was a decrease in the number of consultations. There was also a decrease in the frequency of conjunctival pathology consultations. These changes may bring to light not only the use that people make of the emergency department, but also the new trends in ophthalmological conditions derived from the hygienic habits that the COVID-19 pandemic has established.
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COVID-19 , COVID-19/epidemiologia , Emergências , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2RESUMO
Ubiquity (devices becoming part of the context) and transparency (devices not interfering with daily activities) are very significant in healthcare monitoring applications for elders. The present study undertakes a scoping review to map the literature on sensor-based unobtrusive monitoring of older adults' frailty. We aim to determine what types of devices comply with unobtrusiveness requirements, which frailty markers have been unobtrusively assessed, which unsupervised devices have been tested, the relationships between sensor outcomes and frailty markers, and which devices can assess multiple markers. SCOPUS, PUBMED, and Web of Science were used to identify papers published 2010-2020. We selected 67 documents involving non-hospitalized older adults (65+ y.o.) and assessing frailty level or some specific frailty-marker with some sensor. Among the nine types of body worn sensors, only inertial measurement units (IMUs) on the waist and wrist-worn sensors comply with ubiquity. The former can transparently assess all variables but weight loss. Wrist-worn devices have not been tested in unsupervised conditions. Unsupervised presence detectors can predict frailty, slowness, performance, and physical activity. Waist IMUs and presence detectors are the most promising candidates for unobtrusive and unsupervised monitoring of frailty. Further research is necessary to give specific predictions of frailty level with unsupervised waist IMUs.
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Fragilidade , Idoso , Exercício Físico , Fragilidade/diagnóstico , Humanos , PunhoRESUMO
The present paper describes a system for older people to self-administer the 30-s chair stand test (CST) at home without supervision. The system comprises a low-cost sensor to count sit-to-stand (SiSt) transitions, and an Android application to guide older people through the procedure. Two observational studies were conducted to test (i) the sensor in a supervised environment (n = 7; m = 83.29 years old, sd = 4.19; 5 female), and (ii) the complete system in an unsupervised one (n = 7; age 64-74 years old; 3 female). The participants in the supervised test were asked to perform a 30-s CST with the sensor, while a member of the research team manually counted valid transitions. Automatic and manual counts were perfectly correlated (Pearson's r = 1, p = 0.00). Even though the sample was small, none of the signals around the critical score were affected by harmful noise; p (harmless noise) = 1, 95% CI = (0.98, 1). The participants in the unsupervised test used the system in their homes for a month. None of them dropped out, and they reported it to be easy to use, comfortable, and easy to understand. Thus, the system is suitable to be used by older adults in their homes without professional supervision.
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Teste de Esforço , Avaliação Geriátrica/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Postura Sentada , Posição OrtostáticaRESUMO
E. faecalis is a commensal bacterium with specific strains involved in opportunistic and nosocomial infections. Therefore, it is important to know how the strains of this species are selected in the gut. In this study, fifteen E. faecalis strains, isolated over twelve weeks from the faeces of mice fed standard chow or one of three high fat diets enriched with extra virgin olive oil, refined olive oil or butter were subjected to a genetic "Multilocus Sequence Typing" study that revealed the presence of mainly two genotypes, ST9 and ST40, the latter one prevailing at the end of the research. A V3-V5 sequence comparison of the predominant ST40 strain (12B3-5) in a metagenomic study showed that this sequence was the only E. faecalis present in the mouse cohort after twelve weeks. The strain was subjected to a comparative proteomic study with a ST9 strain by 2D electrophoresis and mass spectrometry. After comparing the results with a E. faecalis database, unshared entries were compared and 12B3-5 showed higher antimicrobial production as well as greater protection from environmental factors such as xenobiotics, oxidative stress and metabolite accumulation, which could be the reason for its ability to outcompete other possible rivals in an intestinal niche.
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Proteínas de Bactérias/metabolismo , Dieta Hiperlipídica/efeitos adversos , Enterococcus faecalis/classificação , Tipagem de Sequências Multilocus/métodos , Animais , Dieta Hiperlipídica/classificação , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Genótipo , Masculino , Camundongos , Prevalência , ProteômicaRESUMO
Lower-limb strength is a marker of functional decline in elders. This work studies the feasibility of using the quasi-periodic nature of the distance between a subjects' back and the chair backrest during a 30-s chair-stand test (CST) to carry out unsupervised measurements based on readings from a low-cost ultrasound sensor. The device comprises an ultrasound sensor, an Arduino UNO board, and a Bluetooth module. Sit-to-stand transitions are identified by filtering the signal with a moving minimum filter and comparing the output to an adaptive threshold. An inter-rater reliability (IRR) study was carried out to validate the device ability to count the same number of valid transitions as the gold-standard manual count. A group of elders (age: mean (m) = 80.79 years old, SD = 5.38; gender: 21 female and seven male) were asked to perform a 30-s CST using the device while a trained nurse manually counted valid transitions. Ultimately, a moving minimum filter was necessary to cancel the effect of outliers, likely produced because older people tend to produce more motion artefacts and, thus, noisier signals. While the intra-class correlation coefficient (ICC) for this study was good (ICC = 0.86, 95% confidence interval (CI) = 0.73, 0.93), it is not yet clear whether the results are sufficient to support clinical decision-making.
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Técnicas Biossensoriais , Fragilidade/diagnóstico , Monitorização Fisiológica , Força Muscular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Fragilidade/diagnóstico por imagem , Fragilidade/fisiopatologia , Humanos , Extremidade Inferior/diagnóstico por imagem , Extremidade Inferior/fisiopatologia , Masculino , Processamento de Sinais Assistido por Computador , UltrassonografiaRESUMO
A comparative study on potential risks was carried out in a collection of 50 enterococci isolated from faeces of mice fed a standard or a high-fat diet enriched with extra virgin olive oil, refined olive oil or butter, at the beginning, after six weeks and after twelve weeks of experiments. Strains were biochemically assessed and genetically characterized. E. faecalis and E. casseliflavus were the most frequently isolated species in any diet and time points. Apart from the fact of not having isolated any strain from the virgin olive oil group during the last balance, we found statistically significant differences p < 0 . 05 among the diets in the percentage of antibiotic resistance and in the presence of the enterococcal surface protein gene (esp), as well as a tendency p < 0 . 1 for the presence of the tyrosine decarboxylase gene (tdc) to increase over time in the group of isolates from the standard diet. When the resistance of the strains to virgin or refined olive oil was studied, only the group of enterococci from high fat diets showed a significantly higher percentage of resistance to refined olive oil p < 0 . 05 , while both types of oil equally inhibited those isolated from the standard diet p > 0 . 05 .
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Dieta Hiperlipídica , Resistência Microbiana a Medicamentos , Enterococcus/isolamento & purificação , Fezes/microbiologia , Animais , Aminas Biogênicas/metabolismo , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Enterococcus/patogenicidade , Masculino , Camundongos Endogâmicos ICR , Azeite de Oliva/farmacologia , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Fatores de Virulência/metabolismoRESUMO
Extra virgin olive oil (EVOO) has been reported to have a distinct influence on gut microbiota in comparison to other fats, with its physiological benefits widely studied. However, a large proportion of the population consumes olive oil after a depurative process that not only mellows its taste, but also deprives it of polyphenols and other minority components. In this study, we compare the influence on the intestinal microbiota of a diet high in this refined olive oil (ROO) with other fat-enriched diets. Swiss Webster mice were fed standard or a high-fat diet enriched with EVOO, ROO, or butter (BT). Physiological parameters were also evaluated. At the end of the feeding period, DNA was extracted from feces and the 16S rRNA was pyrosequenced. The group fed ROO behaved differently to the EVOO group in half the families with statistically significant differences among the diets, with higher comparative levels in three families-Desulfovibrionaceae, Spiroplasmataceae, and Helicobacteraceae-correlating with total cholesterol. These results are again indicative of a link between specific diets, certain physiological parameters and the prevalence of some taxa, but also support the possibility that polyphenols and minor components of EVOO are involved in some of the proposed effects of this fat through the modulation of the intestinal microbiota.
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The type of fat in the diet determinates the characteristics of gut microbiota, exerting a major role in the development of metabolic syndrome. We hypothesize that a diet enriched with extra virgin olive oil (EVOO) has a distinctive effect on the intestinal microbiome in comparison with an enriched butter diet (BT) and this effect is related to the physiological benefits exerted by EVOO. Swiss Webster mice were fed standard (SD) or two high fat diets enriched with EVOO or butter. Hormonal, physiological and metabolic parameters were evaluated. At the end of the feeding period, DNA was extracted from faeces and the 16S rRNA genes were pyrosequenced. Among the main significant differences found, BT triggered the highest values of systolic blood pressure, correlating positively with the percentage of Desulfovibrio sequences in faeces, which in turn showed significantly higher values in BT than in EVOO. EVOO had the lowest values of plasmatic insulin, correlating inversely with Desulfovibrio, and had the lowest plasmatic values of leptin which correlated inversely with Sutterellaceae, Marispirillum and Mucilaginibacter dageonensis, the three showing significantly higher percentages in EVOO. The lowest total cholesterol levels in plasma were detected in SD, correlating positively with Prevotella and Fusicatenibacter, both taxa with significantly greater presence in SD. These results may be indicative of a link between specific diets, certain physiological parameters and the prevalence of some taxa, supporting the possibility that in some of the proposed effects of virgin olive oil the modulation of intestinal microbiota could be involved.
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Manteiga , Dieta , Modelos Animais de Doenças , Microbioma Gastrointestinal , Síndrome Metabólica/fisiopatologia , Azeite de Oliva , Animais , Fezes/microbiologia , Masculino , Camundongos , RNA Ribossômico 16S/genéticaRESUMO
Fat type in diet is responsible for specific changes in gut microbiota (GM). Extra virgin olive oil (EVOO) has been shown to be beneficial for blood pressure and to produce effects on GM. To analyze the cause-effect relationship between intestinal microbial changes and blood pressure, we studied the effect of EVOO on fecal microbiota and systolic blood pressure (SBP) levels in spontaneously hypertensive rats (SHR). SHR were fed either an enriched EVOO diet or a standard diet for a period of 12 weeks. At the end of the experimental period, the microbial profiles in the feces were studied in both groups by using PCR-denaturing gradient gel electrophoresis. Real-time PCR was used to quantify the selected bacterial groups. The results demonstrated significant differences when using Lactobacillus (p<0.05), clostridia XIV (p<0.01) and universal (p<0.05) primers. A significant (r=-0.475; p=0.04) inverse correlation between the abundance of clostridia XIV and SBP, which depends on the type of diet, was also observed. Finally, the results suggested an increase in the microbial diversity of the feces of the animals fed the EVOO diet. These results strongly connect the pattern of GM in SHR fed a diet enriched with EVOO to the lower levels of SBP observed in these animals at the end of the feeding period.
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Pressão Sanguínea/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Azeite de Oliva/farmacologia , Animais , Eletroforese em Gel de Gradiente Desnaturante , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Lactobacillus/efeitos dos fármacos , Masculino , RNA Ribossômico 16S , Ratos Endogâmicos SHRRESUMO
Manzanilla Aloreña (or Aloreña) table olives are naturally fermented traditional green olives with a denomination of protection (DOP). The aim of this study was to search for lactic acid bacteria (LAB) with technological properties of interest for possible inclusion in a starter or protective culture preparation or also as probiotics. A collection of 144 LAB obtained from Aloreña green table olives naturally-fermented by four small-medium enterprises (SMEs) from Málaga (Spain), including lactobacilli (81.94%), leuconostocs (10.42%) and pediococci (7.64%) were studied. REP-PCR clustering and further identification of strains by sequencing of phes and rpo genes revealed that all lactobacilli from the different SMEs were Lactobacillus pentosus. Pediococci were identified as Pediococcus parvulus (SME1) and leuconostocs as Leuconostoc pseudomesenteroides (SME1 and SME4). Genotyping revealed that strains were not clonally related and exhibited a considerable degree of genomic diversity specially for lactobacilli and also for leuconostocs. Some strains exhibit useful technological properties such as production of antimicrobial substances active against pathogenic bacteria such as Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Streptococcus mutans and Salmonella enterica, utilization of raffinose and stachyose, production of bile salt hydrolase, phytase and haeme-dependent catalase activities, growth at 10 °C and in the presence of 6.5% NaCl, good acidifying capacity and also resistance to freezing. However, none of the isolates showed protease or amylase activity, and also did not exhibit biogenic amine production from histidine, ornithine, cysteine or tyrosine. On the basis of data obtained, selected strains with potential traits were tested for their survival at low pH and their tolerance to bile salts, and the survival capacity demonstrated by some of the analysed strains are encouraging to further study their potential as probiotics.