Microbiota intestinal y su relación con agentes oportunistas vinculados a las epidemias / Gut microbiota and its relationship with opportunistic agents linked to epidemics

Resumen Existen epidemias silenciosas asociadas al estrés y a los malos hábitos de alimentación, tan importantes como las epidemias tradicionales asociadas a la pobreza, a problemas geográficos y climáticos. Numerosos estudios se suman al importante papel de un patrón estable de la microbiota intestinal que favorece el estado saludable en los seres humanos y por lo tanto, su posible implicación en la incidencia y prevalencia de enfermedades que pueden convertirse en epidémicas. En esta revisión se analiza el estado actual de la relación entre los factores demográficos, geográficos, ambientales, patrones de consumo de alimentos con la microbiota intestinal y la aparición de epidemias de origen microbiano, metabólico e inmunológico. Se apoya la iniciativa promovida internacionalmente para la creación de plataformas metagenómicas que contribuyan al estudio del patrón de la microbiota intestinal, el seguimiento epidemiológico y la prevención de las enfermedades epidémicas asociadas con su alteración, así como el diseño de métodos rápidos y económicos para la complementación de estos estudios.

Abstract Silent epidemics associated with stress and unhealthy eating habits are as important as traditional epidemics related to poverty, geographical and climate problems. Many studies incorporate the important role of a stable pattern of gut microbiota that favours the human health status and therefore, its possible implication in incidence and prevalence of diseases that can become epidemics. In this review, the current state-of-art is analysed in terms of relationship between demographic, geographic, environmental factors, and habits with the gut microbiota pattern and the onset of epidemics of microbial, metabolic and immunological origin. The internationally promoted initiative for the creation of metagenomic platforms contributing to studies of the gut microbiota pattern for the epidemiological monitoring and prevention of epidemic diseases associated with its alteration is fostered, as well as the design of rapid and economic methods to complement these studies.

Resumo Existem epidemias silenciosas associadas ao estresse, maus hábitos alimentares, tão importantes quanto as epidemias tradicionais associadas à pobreza, problemas geográficos e climáticos. Numerosos estudos contribuem para o importante papel de um padrão estável de microbiota intestinal que favorece o estado saudável em seres humanos e, portanto, sua possível comprometimento na incidência e prevalência de doenças que podem se tornar epidêmicas. Esta revisão analisa o estado atual da relação entre fatores demográficos, geográficos, ambientais, padrões de consumo de alimentos com a microbiota intestinal e o aparecimento de epidemias de origem microbiana, metabólica e imunológica. É fornecido apoio à iniciativa promovida internacionalmente para a criação de plataformas metagenômicas que contribuam para o estudo do padrão da microbiota intestinal, monitoramento epidemiológico e prevenção de doenças epidêmicas associadas à sua alteração, bem como o desenho de métodos rápidos e baratos para a complementação desses estudos.

Composition of the bacterial community in the gastrointestinal tract of Kunming mice

Background: The intestinal bacterial community has an important role in maintaining human health. Dysbiosis is a key inducer of many chronic diseases including obesity and diabetes. Kunming mice are frequently used as a model of human disease and yet little is known about the bacterial microbiome resident to the gastrointestinal tract. Results: We undertook metagenomic sequencing of the luminal contents of the stomach, duodenum, jejunum, ileum, cecum, colon, and rectum of Kunming mice. Firmicutes was the dominant bacterial phylum of each intestinal tract and Lactobacillus the dominant genus. However, the bacterial composition differed among the seven intestinal tracts of Kunming mice. Compared with the small intestine, the large intestine bacterial community of Kunming mice is more stable and diverse. Conclusions: To our knowledge, ours is the first study to systematically describe the gastrointestinal bacterial composition of Kunming mice. Our findings provide a better understanding of the bacterial composition of Kunming mice and serves as a foundation for the study of precision medicine.

Type 2 diabetes mellitus-related environmental factors and the gut microbiota: emerging evidence and challenges

The gut microbiota is a group of over 38 trillion bacterial cells in the human microbiota that plays an important role in the regulation of human metabolism through its symbiotic relationship with the host. Changes in the gut microbial ecosystem are associated with increased susceptibility to metabolic disease in humans. However, the composition of the gut microbiota in those with type 2 diabetes mellitus and in the pathogenesis of metabolic diseases is not well understood. This article reviews the relationship between environmental factors and the gut microbiota in individuals with type 2 diabetes mellitus. Finally, we discuss the goal of treating type 2 diabetes mellitus by modifying the gut microbiota and the challenges that remain in this area.

Evidencia molecular de la ocurrencia de bacterias celulolíticas del género Cohnella en especies neotropicales de Nasutitermitinae colectadas en el NEA / Molecular evidence that cellulolytic bacterial genus Cohnella is widespread among Neotropical Nasutitermitinae from NE Argentina

Cohnella is a highly cellulolytic bacterial genus, which can be found in a variety of habitats. The aim of this study was to assess its presence in the digestive tract of termite species collected in North-eastern Argentina: Nasutitermes aquilinus, N. corniger and Cortaritermes fulviceps. Gut homogenates were incubated with cellulosic substrate for bacterial growth. Bacterial 16S rDNA was partially amplified using new primers for Cohnella spp. and cloned. Sequences obtained showed highest similarity (97.2-99.9%) with those of Cohnella spp. previously reported from diverse environments. Phylogenetic analysis tended to group the clones according to their host species and sampling sites. These results indicate the association of Cohnella-related intestinal symbionts with three common Neotropical termites. Their potential industrial application encourages further research.

Cohnella es un género de bacterias celulolíticas que puede ser encontrado en una variedad de hábitats. El propósito de este estudio fue registrar su presencia en el tracto digestivo de termitas (Nasutitermes aquilinus, N. corniger y Cortaritermes fulviceps) colectadas en el noreste argentino (NEA). Se incubaron homogenados de intestinos en sustrato celulósico para multiplicar las bacterias. Utilizando nuevos cebadores para Cohnella spp., se amplificó una porción del ADN ribosomal 16S bacteriano, el cual fue posteriormente clonado. Las secuencias obtenidas mostraron su mayor porcentaje de similitud (97,2-99,9%) con Cohnella spp., previamente reportadas en diversos ambientes. El análisis filogenético tendió a agrupar a los clones de acuerdo a la especie hospedante y al sitio de muestreo. Estos resultados indican que especies de termitas frecuentes en el NEA albergan simbiontes intestinales relacionados con el género Cohnella. Las potenciales aplicaciones industriales de estos microorganismos animan a profundizar los estudios.

Desarrollo y cambios con la edad en el tubo digestivo, hígado y páncreas / Digestive tract, liver and pancreas: development and changes with age

An adequate functioning of the digestive tract, liver and pancreas is fundamental to providing the organism with the necessary conditions for its development and maintaining its digestive and systemic homeostasis. Life expectancy has increased, it is estimated that adults over 65 years old by 2050, will represent 25% of the local population. The morphological and functional changes associated with aging in the digestive system, liver and pancreas are modest except for those that occur in the microbiota. Recently it has been possible to establish the contribution of the microbiota to life expectancy and establish a link between gastrointestinal microbiota, inflammation associated with aging (inflammaging) and survival. This represents a shift in the paradigm of our understanding physiology, chronic diseases, neoplasms and for the development of new therapies.

Un adecuado funcionamiento del tubo digestivo, hígado y páncreas es fundamental para poder brindar al organismo las condiciones necesarias para su desarrollo y mantener su homeostasis digestiva y sistémica. La expectativa de vida se ha incrementado, estimándose a nivel nacional que para el año 2050 los adultos mayores de 65 años representarán el 25% de la población. Los cambios morfológicos y funcionales asociados al envejecimiento en el aparato digestivo, hígado y páncreas son modestos a excepción, de los que se producen en la microbiota. Recientemente se ha podido establecer la contribución de la microbiota a la esperanza de vida y establecer un nexo entre microbiota gastrointestinal, inflamación asociada al envejecimiento y sobrevida. Esto representa un cambio en el paradigma sobre cómo comprendemos la fisiología, las patologías crónicas, neoplásicas y en el desarrollo de nuevas terapias.

¿Qué sabemos de la importancia de la microbiota intestinal a lo largo de la vida? / What do we know about intestinal microbiota through the life cycle?

Over the last decades, modern lifestyle and environment have contributed to a shift in gut microbial colonization patterns and composition. Not only intestinal but also extraintestinal disorders have been proposed to be linked to changes in the gut microbiome. There is increasing evidence from clinical, epidemiologic and animal studies exploring associations between the dysbiotic microbiome and an increased risk of allergic, inflammatory, autoimmune, and metabolic diseases. The fetus is essentially sterile until the amniotic sac ruptures. After that, the maternal microbiota of the mouth, intestine, vagina and urinary tract contribute to the initial seeding of neonatal microbiota. Newborns are mainly inoculated at birth in the passage through the birth canal (vertical transmission). A number of exposure events occur afterwards (horizontal transmission), and by age 2, an infant's microbiota composition becomes indistinguishable from that of an adult. In mammalian evolution, the potential loss or change in vertical transmission of microbiota from mother to offspring could be compensated through horizontally transmitted microbiota (fecally contaminated drinking and bathing water, frequent physical contact, social crowding, and large families). However, the progressive loss of vertically transmitted microbiota without horizontal replacement represents a cumulative birth cohort phenomenon. Events that decrease microbiota diversity have been classically associated with risk of disease

En las últimas décadas, el estilo de vida y el ambiente moderno, han contribuido a un cambio en los patrones y la composición de colonización microbiana intestinal. No sólo se ha propuesto que los trastornos intestinales, sino también los extraintestinales, estarían relacionados con cambios en la microbioma intestinal. Cada vez hay más evidencias de estudios clínicos, epidemiológicos y en animales que exploran las asociaciones entre el microbioma disbiótico y un mayor riesgo de enfermedades alérgicas, inflamatorias, autoinmunes y metabólicas. El feto es esencialmente estéril hasta que el saco amniótico se rompe. Después de eso, la microbiota materna de la boca, el intestino, la vagina y el tracto urinario contribuye a la siembra inicial de la microbiota neonatal. Los recién nacidos se inoculan principalmente al nacer en el pasaje a través del canal de parto (transmisión vertical). Después de una serie de eventos de exposición (transmisión horizontal), a los 2 años, la composición de microbiota de un bebé se vuelve indistinguible de la de un adulto. En la evolución de los mamíferos, la pérdida o cambio potencial en la transmisión vertical de la microbiota de la madre a la descendencia podría compensarse mediante la microbiota transmitida horizontalmente (agua potable y de baño contaminada con heces, contacto físico frecuente, aglomeración social y familias numerosas). Sin embargo, la pérdida progresiva de microbiota transmitida verticalmente sin reemplazo horizontal representa un fenómeno de cohorte de nacimiento acumulativo. Los eventos que disminuyen la diversidad de la microbiota se han asociado clásicamente con el riesgo de enfermedad.

Dietas altas en grasas y sus efectos sobre el intestino / Diets high in fats and their effects on the intestine

El objetivo de esta revisión fue exponer el conocimiento actual sobre la relación existente entre dietas altas en grasa (DAG), alteraciones morfológicas de la mucosa intestinal, efectos inflamatorios y cáncer intestinal. Las DAG inicialmente producen aumento de la microbiota patógena, lo que reduce la cantidad y calidad de la secreción de los exocrinocitos caliciformes, disminuyendo la efectividad de la barrera intestinal. Las bacterias y sus lipopolisacaridos (LPS) promueven la secreción de citoquinas proinflamatorias activando vías de inflamación, que a su vez afectan la integridad de las uniones intercelulares alterando la barrera intestinal. Lo anterior, permite que los LPS ingresen a la lámina propia y circulación sanguínea produciendo inflamación local y sistémica. Así mismo, las DAG generan efectos nocivos en la morfología y función de la mucosa gastrointestinal lo que podría favorecer el desarrollo de cáncer. Lo anterior, podría deberse a que el consumo de DAG es capaz de aumentar la proliferación de células de la mucosa y el número y proliferación de células madres tumorales en el intestino.

The aim of this review was to present current knowledge about the relationship between high fat diets (HFD), morphological alterations of intestinal mucosa, inflammatory effects and intestinal cancer. The HFD initially produces an increase in the pathogenic microbiota, which reduces quantity and quality of secretion of goblet cells, decreasing the effectiveness of intestinal barrier. Bacteria and their lipopolysaccharides (LPS) stimulate the secretion of proinflammatory cytokines by activating inflammation pathways, which in turn affect the integrity of intercellular junctions by changing intestinal barrier. The above allows the LPS enter to lamina propria and blood circulation producing local and systemic inflammation. Likewise, HFD generate deleterious effects on morphology and function of gastrointestinal mucosa, which could favor the development of cancer. This could be due to the fact that consumption of HFD is capable of increasing proliferation of mucosal cells and number and proliferation of tumor stem cells in the intestine.

Inocuidade micotoxicológica e viabilidade de Aspergillus spp com potencial probiótico provenientes do trato digestório bovino / Mycotoxicological safety and viability of Aspergillus spp with probiotic potential from the bovine digestive tract]

Objetivou-se, com a presente pesquisa, avaliar a viabilidade de Aspergillus spp. com potencial probiótico durante o armazenamento e diante da pressão da microbiota autóctone, bem como a tolerância aos principais ácidos graxos da fermentação ruminal. Verificou-se também a inocuidade micotoxicológica desses isolados fúngicos cultivados em meio de cultivo sólido. Foram avaliados 20 isolados de Aspergillus spp., provenientes do trato gastrointestinal de bovinos criados em Urochloa decumbens lignificada. Esses fungos foram identificados por análise de sequências do DNAr e foram selecionados por apresentarem expressivo potencial celulolítico. O método vapor de amônia foi utilizado para detecção de cepas produtoras de micotoxinas. Os isolados foram avaliados quanto à viabilidade de crescimento em fluido ruminal por até 96 horas e estocagem em condições ambientais. Observou-se que os fungos avaliados não produziram aflatoxinas e que 95% dos isolados apresentaram resistência aos ácidos ruminais. Dois isolados, selecionados a partir das análises anteriores, apresentaram viabilidade sob a pressão da microbiota autóctone e de metabólitos do ecossistema ruminal e permanecem viáveis por, no mínimo, dois anos. Conclui-se que os isolados do gênero Aspergillus selecionados nesta pesquisa apresentam características fisiológicas para serem utilizados com aditivos microbianos ou probióticos para o ambiente ruminal.(AU)

The aims in this study were to evaluate the viability of Aspergillus spp. with probiotic potential during storage, pressure of autochthonous microbiota and tolerance to the main fatty acids of ruminal fermentation. The mycotoxicological safety was also verified. Twenty isolates from the gastrointestinal tract of cattle raised in lignified Urochloa decumbens were identified by rDNA sequence analysis and were previously selected because they showed significant cellulolytic potential. The ammonia vapor method was used to detect the production of mycotoxins. The isolates were evaluated for viability of ruminal fluid growth for up to 96 hours and storage under environmental conditions. The evaluated fungi did not produce aflatoxins, and 95% of them had resistance to ruminal acids. Two isolates, selected according these tests, presented viability on autochthonous microbiota pressure and metabolites from the ruminal ecosystem and remain viable for at least two years. In this research, the selected Aspergillus spp. isolates present physiological characteristics to be used with microbial additives or probiotic.(AU)

Exogenous enzyme complex prevents intestinal soybean meal-induced enteritis in Mugil liza (Valenciennes, 1836) juvenile

ABSTRACT Four soybean meal-based diets containing increasing levels of an enzyme complex (E50, E100, E150 and E200 at 50, 100, 150 and 200 g ton-1, respectively) and one soybean meal-based diet without the enzyme complex (E0) were fed in triplicate to M. liza juveniles in a semi-static flow system with 20 fish per tank for 75 days. There were no differences between the treatments for animal performance parameters, but fish fed the enzyme complex treatment exhibited significantly (P<0.05) higher values of calcium bone retention compared with control fish. Although there was no relationship between bacterial counts in different sections of the gastrointestinal tract or enzyme levels, filamentous bacteria were increased in E50 compared with E150. All of the treatments resulted in higher bacterial counts in the stomach than in intestinal segments. Histological screening showed serious to moderate infiltration of inflammatory cells, modification in villus morphology and necrosis in some cases in fish fed the E0 diet. In addition, fish from the E0 treatment exhibited significantly (P<0.05) lower lipid deposition in the peritoneal cavity. Therefore, the use of low levels of exogenous enzyme is recommended in diets for M. liza when soybean meal is used as the main source of protein.

Colonización e infección en el neonato: ¿Hay un rol para el uso de la clorhexidina en la prevención de infecciones? / Colonization and infection in the newborn infant: Does chlorhexidine play a role in infection prevention?

Las infecciones asociadas al cuidado de la salud son un tema de gran importancia en los recién nacidos, teniendo en cuenta su alta carga de morbilidad, mortalidad y secuelas a largo plazo. En prematuros, se ha demostrado que la colonización de la piel y del tracto gastrointestinal sufre variaciones respecto a neonatos a término y sanos, con un riesgo de mayor exposición a microorganismos intrahospitalarios por la mayor probabilidad de ingresar a unidades de cuidado intensivo neonatal por aspectos inherentes a su prematurez. El presente documento revisa la colonización normal, los cambios que se observan con la hospitalización, la prematurez y el potencial papel de la clorhexidina en la prevención de la transmisión de microorganismos resistentes, así como sus efectos secundarios en los neonatos en Cuidado Intensivo Neonatal.

Healthcare-associated infections are a major problem in newborn infants, considering their high morbidity, mortality, and long-term sequelae. In preterm infants, it has been shown that skin and gastrointestinal tract colonization undergoes variations compared to healthy term infants, and that preterm infants are more exposed to nosocomial microorganisms given their higher probability of being admitted to the neonatal intensive care unit where they are cared for. This document reviews normal colonization, the changes observed during hospitalization, prematurity, and the potential role of chlorhexidine in the prevention of resistant microorganism transmission, as well as its side effects in newborn infants admitted to the neonatal intensive care unit.

Opioid peptides and gastrointestinal symptoms in autism spectrum disorders

Autism spectrum disorders (ASDs) are characterized by deficits in the individual’s ability to socialize, communicate, and use the imagination, in addition to stereotyped behaviors. These disorders have a heterogenous phenotype, both in relation to symptoms and regarding severity. Organic problems related to the gastrointestinal tract are often associated with ASD, including dysbiosis, inflammatory bowel disease, exocrine pancreatic insufficiency, celiac disease, indigestion, malabsorption, food intolerance, and food allergies, leading to vitamin deficiencies and malnutrition. In an attempt to explain the pathophysiology involved in autism, a theory founded on opioid excess has been the focus of various investigations, since it partially explains the symptomatology of the disorder. Another hypothesis has been put forward whereby the probable triggers of ASDs would be related to the presence of bacteria in the bowel, oxidative stress, and intestinal permeability. The present update reviews these hypotheses.

Phytoplankton composition of the water and gastrointestinal tract of the mussel Diplodon enno (Ortmann, 1921) from São Francisco river (Bahia, Brazil) / Composição fitoplanctônica da água e do trato gastrointestinal do molusco Diplodon enno (Ortmann) do rio São Francisco (BA - Brasil)

Abstract The knowledge on diet composition of the freshwater mussel Diplodon enno (Ortmann) would aid in its culture and propagation allowing, this way, the replacement of natural endangered populations in Brazil. Microalgae are the main food source for captive mussels and unionids have displayed an ability to sort algae based on the cellular characteristics prior to ingestion. The main objective of the present work is to analyze the phytoplankton composition of the water from and of the gastrointestinal contents of the mussel D. enno, as an initial step for development of a suitable rearing diet. Therefore, water samples and bivalve specimens were collected from S. Francisco River, city of Paulo Afonso, Bahia, Brazil. The microalgal composition found in water and stomach/gut content samples was very diverse being represented by the following divisions: Cyanophyta, Chlorophyta, Dinophyta and Heterokontophyta (Diatoms). Concerning the relative abundance of microalgae divisions, it is possible to state, for the water and gastrointestinal contents, that Cyanophyta represents 15% and 14%, Chlorophyta 54% in both, Heterokontophyta 31% and 27% and Dinophyta 0% and 5%, respectively. According to the Brazilian CETESB criteria for phytoplankton species classification, 50% of Cyanophyta and 15% of Chlorophyta species observed in the water samples were classified as “very frequent”, as were 68% of Heterokontophyta and 33% of Chlorophyta species in the gut/stomach tract samples. Focusing at a species level, although in the water only Coelastrum sp. and Chroococcus sp. were observed in 100% and 75% of the samples, respectively, in the gastrointestinal tract the species Staurastrum sp., Aulacoseira sp., Scenedesmus sp. and Fragilaria crotonensis occurred in 80% to 100% of the samples. The present results showed that D. enno feeds not only on small chlorophytes microalgae, due to their convenient size that facilitates higher feeding rates, but also on large size diatoms, due to a possible nutritional advantage for the bivalves. Thus, a diet composed by large diatoms and small chlorophytes microalgae may be considered as the most reasonable for the maintenance of D. enno populations.

Resumo O conhecimento da composição da dieta do molusco de água doce Diplodon enno é de extrema importância para a sua cultura e propagação, permitindo desta forma a recuperação de populações em perigo de extinção no Brasil. As microalgas são a principal fonte de alimento para moluscos filtradores e os uniónidos sendo selecionadas por estes com base nas suas características celulares. O principal objectivo deste trabalho é analisar a composição fitoplanctônica da água e do conteúdo gastrointestinal do molusco D. enno, de forma a desenvolver uma dieta apropriada ao seu cultivo. Para isso, amostras de água e espécimes de bivalves foram recolhidos do rio São Francisco, cidade de Paulo Afonso, Bahia, Brasil. A composição de microalgas encontrada na água e no conteúdo do estômago/intestino foi muito diversa, sendo representada pelas seguintes divisões: Cyanophyta, Chlorophyta, Dinophyta e Heterokontophyta (diatomáceas). Atendendo à abundância relativa de cada divisão de microalgas, podemos afirmar que na água e no trato gastrointestinal Cyanophyta representa 15% e 14%, Chlorophyta 54% em ambos, Heterokontophyta 31% e 27% e Dinophyta 0% and 5%, respectivamente. De acordo com o critério CETESB de classificação de espécies de fitoplâncton, 50% das espécies de Cyanophyta e 15% das de Chlorophyta observadas nas amostras de água foram classificadas como “muito frequentes”, tal como aconteceu para 68% das espécies de Heterokontophyta e 33% das de Chlorophyta nas amostras do conteúdo do trato gastrointestinal. Realçando as espécies presentes, apesar de apenas Coelastrum sp. e Chroococcus sp. terem sido observadas em 100% e 75% das amostras de água, respectivamente, nas amostras de trato gastrointestinal Staurastrum sp., Aulacoseira sp., Scenedesmus sp. e Fragilaria crotonensis foram identificadas em entre 80% e 100% das amostras. Os resultados deste estudo mostram que D. enno se alimenta não apenas de pequenas microalgas clorófitas, devido ao seu pequeno tamanho que possibilita maiores taxas de filtração, como também de diatomáceas maiores, devido a uma possível vantagem nutricional para os bivalves. Assim sendo, uma dieta composta por diatomáceas e pequenas clorófitas poderá ser considerada a mais indicada para a manutenção de populações de D. enno.

Detection of carboxylesterase and esterase activity in culturable gut bacterial flora isolated from diamondback moth, Plutella xylostella (Linnaeus), from India and its possible role in indoxacarb degradation

Abstract Diamondback moth (DBM), Plutella xylostella (Linnaeus), is a notorious pest of brassica crops worldwide and is resistant to all groups of insecticides. The insect system harbors diverse groups of microbiota, which in turn helps in enzymatic degradation of xenobiotic-like insecticides. The present study aimed to determine the diversity of gut microflora in DBM, quantify esterase activity and elucidate their possible role in degradation of indoxacarb. We screened 11 geographic populations of DBM in India and analyzed them for bacterial diversity. The culturable gut bacterial flora underwent molecular characterization with 16S rRNA. We obtained 25 bacterial isolates from larvae (n = 13) and adults (n = 12) of DBM. In larval gut isolates, gammaproteobacteria was the most abundant (76%), followed by bacilli (15.4%). Molecular characterization placed adult gut bacterial strains into three major classes based on abundance: gammaproteobacteria (66%), bacilli (16.7%) and flavobacteria (16.7%). Esterase activity from 19 gut bacterial isolates ranged from 0.072 to 2.32 µmol/min/mg protein. Esterase bands were observed in 15 bacterial strains and the banding pattern differed in Bacillus cereus – KC985225 and Pantoea agglomerans – KC985229. The bands were characterized as carboxylesterase with profenofos used as an inhibitor. Minimal media study showed that B. cereus degraded indoxacarb up to 20%, so it could use indoxacarb for metabolism and growth. Furthermore, esterase activity was greater with minimal media than control media: 1.87 versus 0.26 µmol/min/mg protein. Apart from the insect esterases, bacterial carboxylesterase may aid in the degradation of insecticides in DBM.

Xylooligosaccharides: an economical prebiotic from agroresidues and their health benefits.

Oligosaccharides and dietary fibres are non-digestible food ingredients that preferentially stimulate the growth of prebiotic Bifidobacterium and other lactic acid bacteria in the gastro-intestinal tract. Xylooligosaccharides (XOS) provide a plethora of health benefits and can be incorporated into several functional foods. In the recent times, there has been an over emphasis on the microbial conversion of agroresidues into various value added products. Xylan, the major hemicellulosic component of lignocellulosic materials (LCMs), represents an important structural component of plant biomass in agricultural residues and could be a potent bioresource for XOS. On an industrial scale, XOS can be produced by chemical, enzymatic or chemo-enzymatic hydrolysis of LCMs. Chemical methods generate XOS with a broad degree of polymerization (DP), while enzymatic processes will be beneficial for the manufacture of food grade and pharmaceutically important XOS. Xylooligomers exert several health benefits, and therefore, have been considered to provide relief from several ailments. This review provides a brief on production, purification and structural characterization of XOS and their health benefits.

Probiotics: an update / Probióticos: informações atualizadas

OBJECTIVE: Triggered by the growing knowledge on the link between the intestinal microbiome and human health, the interest in probiotics is ever increasing. The authors aimed to review the recent literature on probiotics, from definitions to clinical benefits, with emphasis on children. SOURCES: Relevant literature from searches of PubMed, CINAHL, and recent consensus statements were reviewed. SUMMARY OF THE FINDINGS: While a balanced microbiome is related to health, an imbalanced microbiome or dysbiosis is related to many health problems both within the gastro-intestinal tract, such as diarrhea and inflammatory bowel disease, and outside the gastro-intestinal tract such as obesity and allergy. In this context, a strict regulation of probiotics with health claims is urgent, because the vast majority of these products are commercialized as food (supplements), claiming health benefits that are often not substantiated with clinically relevant evidence. The major indications of probiotics are in the area of the prevention and treatment of gastro-intestinal related disorders, but more data has become available on extra-intestinal indications. At least two published randomized controlled trials with the commercialized probiotic product in the claimed indication are a minimal condition before a claim can be sustained. Today, Lactobacillus rhamnosus GG and Saccharomyces boulardii are the best-studied strains. Although adverse effects have sporadically been reported, these probiotics can be considered as safe. CONCLUSIONS: Although regulation is improving, more stringent definitions are still required. Evidence of clinical benefit is accumulating, although still missing in many areas. Misuse and use of products that have not been validated constitute potential drawbacks. .

OBJETIVO: Motivado pelo conhecimento cada vez maior da associação entre o microbioma intestinal e a saúde humana, o interesse nos probióticos vem crescendo cada vez mais. Os autores visaram analisar a última literatura a respeito dos probióticos, de definições a benefícios clínicos com ênfase nas crianças. FONTES DOS DADOS: Foi analisada a literatura relevante de pesquisas do PubMed, do CINAHL e dos últimos consensos. SÍNTESE DOS DADOS: Apesar de um equilíbrio no microbioma estar relacionado à saúde, um desequilíbrio no microbioma ou disbiose está relacionado a vários problemas de saúde no trato gastrointestinal, como diarreia e doença inflamatória intestinal, e fora do trato gastrointestinal, como obesidade e alergia. Nesse contexto, a regulamentação rigorosa dos probióticos a alegações de saúde é urgente, pois a grande maioria desses produtos é comercializada como alimentação (suplementos), alegando benefícios à saúde que frequentemente não são comprovados com evidências clinicamente relevantes. As principais indicações de probióticos são feitas na área da prevenção e tratamento de doenças gastrointestinais, porém mais dados têm sido disponibilizados a respeito de indicações extraintestinais. Pelo menos dois ensaios clínicos controlados e randomizados publicados com o probiótico comercializado na indicação declarada são a condição mínima antes de uma afirmação poder ser mantida. Atualmente, o Lactobacillus rhamnosus GG e Saccharomyces boulardii são as melhores cepas estudadas. Apesar de efeitos adversos terem sido esporadicamente relatados, os probióticos podem ser considerados seguros. CONCLUSÕES: Apesar de a regulamentação estar aumentando, ainda são necessárias definições mais rigorosas. As evidências de benefícios clínicos estão aumentando, apesar de ainda ausentes em várias áreas. O uso inadequado e a utilização de produtos não validados constituem possíveis desvantagens. .

Does the change on gastrointestinal tract microbiome affects host?

During the past decade, studies on the composition of human microbiota and its relation to the host became one of the most explored subjects of the medical literature. The development of high-throughput molecular technologies allowed a deeper characterization of human microbiota and a better understanding of its relationship with health and disease. Changes in human habits including wide use of antimicrobials can result in dysregulation of host–microbiome homeostasis, with multiple consequences. The purpose of this review is to highlight the most important evidence in the literature of host–microbiome interactions and illustrate how these intriguing relations may lead to new treatment and prevention strategies.

Antiviral activity of a Bacillus sp: P34 peptide against pathogenic viruses of domestic animals

P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 10(4.5) TCID50 to 10(2.75) TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections.