Bifidobacterium scardovii aislado de 2 muestras consecutivas de orina / Bifidobacterium scardovii isolated from 2 consecutive urine samples

La especie Bifidobacterium scardovii está constituida por bacilos gram positivos anaerobios facultativos, cuyo desarrollo es estimulado por el CO2 y la anaerobiosis. Excepcionalmente se la ha asociado a infecciones humanas. Se presenta el caso de un paciente anoso con infección urinaria por B. scardovii y Enterococcus faecalis, ambos microorganismos aislados en 2 urocultivos consecutivos. El bacilo no desarrolló en los medios de cultivo habituales, pero sí en agar chocolate en CO2 y en agar Brucella suplementado, incubados durante 72 h a 35°C. La coloración de Gram alertó acerca de su presencia al observarse abundantes bacilos gram positivos irregulares con extremos bifurcados en forma de Y, y escasos cocos gram positivos. Es importante la coloración de Gram en orinas con piuria y la siembra en medios enriquecidos por tiempos prolongados. En este caso, sin el resultado del Gram y con el desarrollo de E. faecalis, no hubiésemos advertido la presencia del agente mayoritario.

Bifidobacterium scardovii species consists of facultative anaerobic gram-positive rods whose growth is stimulated by CO2 and anaerobiosis. Exceptionally it has been associated with infections in humans. An elderly male patient with a urinary tract infection due to B. scardovii and Enterococcus faecalis is presented here; both microorganisms were isolated from two consecutive urine samples. The bacillus did not grow on standard media, but on chocolate agar incubated in CO2 and on supplemented Brucella agar in an anaerobic atmosphere, incubated for 72 h at 35°C. Gram staining with abundant irregular gram-positive rods with Y-shaped ends and some gram-positive cocci alerted to its presence. The importance of the Gram stain test in urine samples with pyuria and the growth on enriched media for long periods is highlighted here. In this case, if we had not had the Gram stain test results, and had considered only the E. faecalis growth, we would have lost the major etiologic agent.

In vivo assay to identify bacteria with ß-glucosidase activity

Background: ß-Glucosidase assay is performed with purified or semipurified enzymes extracted from cell lysis. However, in screening studies, to find bacteria with ß-glucosidase activity among many tested bacteria, a fast method without cell lysis is desirable. In that objective, we report an in vivo ß-glucosidase assay as a fast method to find a ß-glucosidase producer strain. Results: The method consists in growing the strains for testing in a medium supplemented with the artificial substrate p-nitrophenyl-ß-glucopyranoside (pNPG). The presence of ß-glucosidases converts the substrate to p-nitrophenol (pNP), a molecule that can be easily measured in the supernatant spectrophotometrically at 405 nm. The assay was evaluated using two Bifidobacterium strains: Bifidobacterium longum B7254 strain that lacks ß-glucosidase activity and Bifidobacterium pseudocatenulatum B7003 strain that shows ß-glucosidase activity. The addition of sodium carbonate during pNP measurement increases the sensitivity of pNP detection and avoids the masking of absorbance by the culture medium. Furthermore, we show that pNP is a stable enzymatic product, not metabolized by bacteria, but with an inhibitory effect on cell growth. The ß-glucosidase activity was measured as units of enzyme per gram per minute per dry cell weight. This method also allowed the identification of Lactobacillus strains with higher ß-glucosidase activity among several lactobacillus species. Conclusion: This in vivo ß-glucosidase assay can be used as an enzymatic test on living cells without cell disruption. The method is simple, quantitative, and recommended, especially in studies screening for bacteria not only with ß-glucosidase activity but also with high ß-glucosidase activity.

Anaerobic bacteria in the intestinal microbiota of Brazilian children

OBJECTIVE: Changes in the neonatal gut environment allow for the colonization of the mucin layer and lumen by anaerobic bacteria. The aim of the present study was to evaluate Bifidobacterium, Lactobacillus and Lactococcus colonization through the first year of life in a group of 12 Brazilian infants and to correlate these data with the levels of Escherichia coli. The presence of anaerobic members of the adult intestinal microbiota, including Eubacterium limosum and Faecalibacterium prausnitzii, was also evaluated. METHODS: Fecal samples were collected during the first year of life, and 16S rRNA from anaerobic and facultative bacteria was detected by real-time PCR. RESULTS: Bifidobacterium was present at the highest levels at all of the studied time points, followed by E. coli and Lactobacillus. E. limosum was rarely detected, and F. prausnitzii was detected only in the samples from the latest time points. CONCLUSION: These results are consistent with reports throughout the world on the community structure of the intestinal microbiota in infants fed a milk diet. Our findings also provide evidence for the influence of the environment on intestinal colonization due to the high abundance of E. coli. The presence of important anaerobic genera was observed in Brazilian infants living at a low socioeconomic level, a result that has already been well established for infants living in developed countries.

Selection of superior bifidobacteria in the presence of rotavirus

The main purpose of this study was to investigate bifidobacteria flora in fecal samples from children with rotavirus infection and determine the significance of their selected probiotic properties for improvement of health status. Enzyme-linked immunosorbent assay was used to identify rotavirus antigen in fecal samples from 94 patients with gastroenteritis and from 30 without gastroenteritis. Bifidobacteria were identified by selective media, gram reaction, colony morphology, fructose-6-phosphate phosphoketolase enzyme activity and classical identification tests. Exopolysaccharide (EPS) production was identified by phenol-sulphuric acid method. The modified method was then used to identify the quantity of taurocholic and glycocholic acid deconjugation and cholesterol elimination of the strains. Thirty-five of the 94 fecal samples were found positive for rotavirus antigen (37.23%). Bifidobacteria were identified in 59 of the samples. The EPS production ranges were 29.56-102.21 mg/L. The cholesterol elimination rates ranged between 8.36-39.22%. Furthermore, a positive and strong correlation was determined between EPS production and the presence of cholesterol (r=0.984, P<0.001). The deconjugation rates for the sodium glycocholate group was higher than the sodium taurocholate group. Rotavirus (+) bifidobacteria strains had higher EPS production, deconjugation rate and cholesterol elimination compared to bifidobacteria strains isolated from children in the rotavirus (-) sample and without gastroenteritis. Significant differences were observed among groups in all parameters (P<0.05). Given the increased number of rotavirus cases in Turkey and worldwide, it is very important to add superior bifidobacteria in the diets of infected children to improve the intestinal and vital functions.

Evaluation of culture media for selective enumeration of bifidobacteria and lactic acid bacteria

The purpose of this study was to test the suitability of Transgalactosylated oligosaccharides-mupirocin lithium salt (TOS-MUP) and MRS-clindamycin-ciprofloxacin (MRS-CC) agars, along with several other culture media, for selectively enumerating bifidobacteria and lactic acid bacteria (LAB) species commonly used to make fermented milks. Pure culture suspensions of a total of 13 dairy bacteria strains, belonging to eight species and five genera, were tested for growth capability under various incubation conditions. TOS-MUP agar was successfully used for the selective enumeration of both Bifidobacterium animalis subsp. lactis BB-12 and B. breve M-16 V. MRS-CC agar showed relatively good selectivity for Lactobacillus acidophilus, however, it also promoted the growth of Lb. casei strains. For this reason, MRS-CC agar can only be used as a selective medium for the enumeration of Lb. acidophilus if Lb. casei is not present in a product at levels similar to or exceeding those of Lb. acidophilus. Unlike bifidobacteria and coccus-shaped LAB, all the lactobacilli strains involved in this work were found to grow well in MRS pH 5.4 agar incubated under anaerobiosis at 37 °C for 72 h. Therefore, this method proved to be particularly suitable for the selective enumeration of Lactobacillus spp.

Lower bifidobaceeria counts in adult patients with celiac disease on a gluten-free deet / Baixa contagem de bifidobactérias em pacientes adultos com doença celíaca, em dieta isenta de glúten

Context The ingestion of gluten is responsible for the symptoms of Celiac disease, but other environmental factors can also influence. Strains of the Bifidobacterium genus have been shown to afford protection against the inflammatory response and mucosal damage caused by gliadin peptides in vitro. Objectives This study was designed to compare the concentration of fecal bifidobacteria and pH of patients with celiac disease on gluten-free diet and control subjects in order to identify if the imbalance on fecal microbiota still remain during the treatment of celiac disease and identify the necessity of dietary supplementation with pre- or probiotics. Methods It was analyzed the feces of 42 healthy subjects and 14 celiac patients. The bifidobacteria count in feces was done in selective medium BIM-25. Microscopic analysis of the colonies was performed by Gram stain. The identification of the genus Bifidobacterium was performed by determination of fructose-6-phosphate phosphoketolase. Fecal pH was measured using a pH meter. Results The concentration of bifidobacteria per gram of feces was significantly higher in healthy subjects (controls) (1.5 ± 0.63 x108 CFU/g) when compared to celiac patients (2.5 ± 1.5 x107 CFU/g). The fecal pH was not different between celiac patients (7.19 ± 0.521) and controls (7.18 ± 0.522). Conclusions These results suggest that with lower levels of bifidobacteria, celiac patients have an imbalance in the intestinal microbiota, regardless of pH, even while on a gluten-free diet. This fact could favor the pathological process of the disorder. .

Contexto A ingestão do glúten é responsável pelos sintomas da doença celíaca, mas outros fatores ambientais também podem influenciar. Tem sido mostrado que as cepas do género Bifidobacterium proporcionam proteção contra a resposta inflamatória, lesão da mucosa causada por péptidos da gliadina in vitro. Objetivos Este estudo foi desenvolvido para comparar as concentrações de bifidobactérias e pH fecal de pacientes com doença celíaca em dieta isenta de glúten e indivíduos controles, a fim de identificar se o desequilíbrio na microbiota fecal ainda permanece durante o tratamento da doença celíaca e, identificar a necessidade de suplementação alimentar com pré ou probióticos. Métodos Foram analisadas as fezes de 42 indivíduos saudáveis e 14 pacientes com doença celíaca. A contagem de bifidobactérias nas fezes foi feita em meio seletivo BIM-25. A análise microscópica das colônias foi realizada por coloração de Gram. A identificação do género Bifidobacterium foi realizada por determinação de phosphoketolase frutose-6-fosfato. O pH fecal foi medido usando um medidor de pH. Resultados As concentrações de bifidobactérias por grama de fezes foi significativamente mais elevada nos indivíduos saudáveis (controles) (1,5 ± 0,63 x108 UFC/g), quando comparada com pacientes com doença celíaca (2,5 ± 1,5 x107 UFC/g). O pH fecal não foi diferente entre pacientes celíacos (7,19 ± 0,521) e controles (7,18 ± 0,522). Conclusões Estes resultados sugerem que, com concentrações inferiores de bifidobactérias, pacientes com doença celíaca tem um desequilíbrio na microbiota intestinal, independentemente do pH, mesmo durante uma dieta isenta de ...

Desenvolvimento de sorvete simbiótico de graviola ( Annona muricata L. ) com teor reduzido de gordura e avaliação da resistência gastrointestinal dos probióticos in vitro / Development of low-fat symbiotic graviola ( Annona muricata L. ) ice-cream and evaluation of the probiotics gastrointestinal in vitro resistance

O presente trabalho objetivou avaliar o efeito da adição de inulina (I) e a substituição parcial da gordura do leite (G) pelo concentrado de proteína de soro de leite (WPC) sobre a sobrevivência dos probióticos Lactobacillus acidophilus NCFM e Bifidobacterium animalis subsp. lactis HN019 em sorvete de graviola com teor reduzido de gordura, ao longo do período de armazenamento e frente às condições encontradas no trato gastrointestinal (TGI) simuladas in vitro. Adicionalmente, avaliou-se a influência desses ingredientes (6% I; 1,5% WPC; 3% e 1,5% G) sobre as características tecnológicas e a aceitabilidade do sorvete funcional. Empregou-se um planejamento fatorial 22, para 4 formulações produzidas, em triplicata, totalizando 12 ensaios: F1- controle (- I, - WPC); F2 (+ I, - WPC); F3 (- I, + WPC) e F4 (+ I, + WPC). Todas as formulações foram armazenadas a -18±3ºC e avaliadas após 2, 28, 56, 84 e 112 dias de armazenamento. A determinação das características tecnológicas foi realizada com as análises de dureza instrumental (em analisador de textura TA-XT2), fração de derretimento, overrun (durante a elaboração do produto) e perfil lipídico. Para o teste de aceitabilidade do produto, utilizou-se uma escala hedônica estruturada de 9 pontos. Elevada viabilidade probiótica foi observada para todas as formulações, com médias de populações acima de 8,0 log UFC/g, não diferindo significativamente durante o armazenamento de 112 dias (p>0,05). B. animalis subsp. lactis HN019 apresentou uma maior resistência em relação a L. acidophilus NCFM quando submetido aos sucos gastrointestinais artificiais, uma vez que a população de NCFM e de HN019 diminuíram, respectivamente, cerca de 5,2 log UFC/g e de 1,2 log UFC/g, durante o armazenamento. O efeito protetor do WPC e/ou I sobre a resistência de L. acidophilus aos sucos gastrointestinais artificiais foi observada no 56º dia e, para B. animalis subsp. lactis no 2º dia de armazenamento (p<0,05). Os sorvetes com WPC apresentaram menores valores de dureza, aos 7º e 112º dias de estocagem (p<0,05). A adição de inulina influenciou no aumento da dureza para F2 após 56 dias e para F4 durante todo período de armazenamento (p<0,05). Os resultados mostraram, também, que a presença do WPC e/ou inulina reduziu a velocidade de derretimento dos sorvetes durante todo o armazenamento (p<0,05). Elevados escores médios (entre 6,8 e 8,0) foram obtidos no teste de aceitabilidade sensorial dos sorvetes probióticos, indicando excelente aceitação pelos consumidores e não diferiram significativamente durante o armazenamento de até 84 dias. Já para F4, a adição do WPC + I aumentou a aceitação do produto após 56 dias (p<0,05). Os resultados obtidos sugerem que a utilização do WPC como substituto parcial da gordura láctea separadamente ou combinada com a inulina pode ser vantajosa no desenvolvimento de sorvete probiótico com baixo teor de gordura, uma vez que a presença desses ingredientes desempenhou um papel importante na proteção dos probióticos contra o efeito dos fluidos gastrointestinais nos testes in vitro. Além deste efeito protetor, a utilização da inulina e WPC também melhorou as características tecnológicas e sensoriais do sorvete funcional reduzido de gordura

This study aimed to assess the effect of the addition of inulin (I) and the partial substitution of the milk fat (MF) by whey protein concentrate (WPC) on Lactobacillus acidophilus NCFM and Bifidobacterium animalis subsp. lactis HN019 viability incorporated in low fat graviola (Annona muricata L.) ice-cream and on probiotic survival under in vitro simulated gastrointestinal conditions throughout 112 days of storage. Moreover, the influence of these ingredients (6% I; 1,5% WPC; 3% and 1,5% MF) on the functional ice-cream technological and sensorial features was also evaluated. Employing a 22 factorial design, four formulations were produced, in triplicates: F1- control (- I, - WPC); F2 (+ I, - WPC); F3 (- I, + WPC) and F4 (+ I, + WPC). The product were stored at -18±3ºC and analyzed after 2, 28, 56, 84, and 112 days of storage. Ice-creams from each trial were used for determination of L. acidophilus and B. animalis subsp. lactis viability in the products and survival in ice-creams submitted to gastrointestinal simulated conditions during storage at -18±3ºC for up to 112 days. For the determination of technological features, instrumental hardness (in TA-XT2 Texture Analyser), melting rate, overrun (during production), and lipid profile were determined. For sensory acceptability evaluation, a 9 point hedonic scale was used. High probiotic viability was observed for all formulations, with mean populations above 8.0 cfu/g and which did not differ significantly throughout 112 days of storage (p>0.05). B. animalis subsp. lactis HN019 resistance to the artificial gastrointestinal juices was higher than for L. acidophilus NCFM, since the NCFM and the HN019 populations decreased approximately 5.2 log cfu/g and 1.2 log cfu/g, respectively, throughout storage. The protective effect of WPC and/or WPC + I on the L. acidophilus resistance to artificial gastrointestinal juices was observed on the 56th day and for B. animalis subsp. lactis on the 2nd day of storage (p<0.05). The ice-creams with WPC presented lower hardness in the 7th and 112nd days of frozen storage (p<0.05). The addition of inulin led to an incresed hardnes for F2 after 56 days and for F4 during the whole storage (p<0.05). The results also showed that the presence of the WPC and/or inulin reduced the ice-creams melting rates during the whole storage (p<0.05). The high mean scores obtained (between 6.8 and 8.0) in the acceptability test indicated that the functional ice-creams evaluated were very well accepted, and did not differ significantly throughout storage of up to 84 days. Except for F4, the addition of the WPC + I improved the acceptability after 56th days of frozen storage (p<0.05). The results suggest that the use of WPC for the partial substitution of the milk fat separately or combined with inulin may be advantageous in the development of low-fat synbiotic ice-cream, since the presence of these ingredients played an important role in the probiotic protection against gastrointestinal juices in the in vitro simulated assays. Besides these protective effects, inulin and WPC also improved the technological and sensory features of the low-fat functional ice-cream

Evaluation of fecal microorganisms of children with cleft palate before and after palatoplasty

This study isolated and quantified intestinal bacteria of children with cleft palate before and after palatoplasty. A prospective study was conducted from May 2007 to September 2008 on 18 children with cleft palate, aged one to four years, of both genders, attending a tertiary cleft center in Brazil for palatoplasty, to analyze the effect of surgical palate repair on the concentration of anaerobes Bacteroides sp, Bifidobacterium sp and microaerophiles Lactobacillus sp in feces of infants with cleft palate before and 24 hours after treatment with cefazolin for palatoplasty. There was significant reduction of Lactobacillus sp (p < 0.002), Bacteroides sp (p < 0.001) and Bifidobacterium sp (p = 0.021) after palatoplasty, revealing that surgery and utilization of cefazolin significantly influenced the fecal microbiota comparing collections before and after surgery. However, due to study limitations, it was not possible to conclude that other isolated factors, such as surgical stress, anesthetics and other medications used in palatoplasty might have a significant influence on the microbiota. Considering the important participation of the intestinal microbiota on both local and systemic metabolic and immunological activities of the host, professionals should be attentive to the possible influence of these changes in patients submitted to cleft repair.

Establishment of the bacterial fecal community during the first month of life in Brazilian newborns

OBJECTIVE: The establishment of the intestinal microbiota in newborns is a critical period with possible long-term consequences for human health. In this research, the development of the fecal microbiota of a group of exclusively breastfed neonates living in low socio-economic conditions in the city of São Paulo, Brazil, during the first month of life, was studied. METHODS: Fecal samples were collected from ten neonates on the second, seventh, and 30th days after birth. One of the neonates underwent antibiotic therapy. Molecular techniques were used for analysis; DNA was extracted from the samples, and 16S rRNA libraries were sequenced and phylogenetically analyzed after construction. A real-time polymerase chain reaction (PCR) was performed on the samples taken from the 30th day to amplify DNA from Bifidobacterium sp. RESULTS: The primary phylogenetic groups identified in the samples were Escherichia and Clostridium. Staphylococcus was identified at a low rate. Bifidobacterium sp. was detected in all of the samples collected on the 30th day. In the child who received antibiotics, a reduction in anaerobes and Escherichia, which was associated with an overgrowth of Klebsiella, was observed throughout the experimental period. CONCLUSION: The observed pattern of Escherichia predominance and reduced Staphylococcus colonization is in contrast with the patterns observed in neonates living in developed countries.

Influence of probiotics on Candida presence and IgA anti-Candida in the oral cavity

Probiotics are defined as microorganisms that promote benefits to host health, mainly by regulating resident microbiota. Disequilibrium in microbiota can favor the growth of opportunist microorganisms and the development of pathologies, like candidosis caused by yeasts of the Candida genus. This work evaluated whether probiotics consumption was able to influence a specific immunological response to Candida and the presence of these yeasts in the oral cavity. Saliva samples were collected from healthy individuals and plated in Dextrose Saboraud Agar with chloramphenicol. Individuals presenting Candida in the oral cavity used the probiotic Yakult LBâ for 20 days, after which new collections and identifications were performed. Anti-Candida IgA analysis was conducted using the ELISA technique. Analysis of the results showed a significant reduction in Candida prevalence (46 percent) and mean Candida CFU/mL counts (65 percent). The Candida species identified were C. albicans (98 percent) and C.tropicalis (2 percent), before and after probiotics consumption. Immunological analysis demonstrated a significant reduction in anti-Candida IgA levels after probiotics use, probably due to less antigenic stimulation. In conclusion, in the individuals studied, probiotics use significantly reduced the amount of Candida in the oral cavity, possibly due to competition between the yeasts rather than by specific secretory immune response stimulation.

Lactobacilos e bifidobactérias nas fezes de crianças escolares de dois estratos socioeconômicos: moradores em uma favela e alunos de uma escola particular / Lactobacilli and bifidobacteria in the feces of schoolchildren of two different socioeconomic groups: children from a favela and children from a private school

OBJETIVO: Determinar o número de colônias de lactobacilos e bifidobactérias nas fezes de crianças escolares, pertencentes a dois estratos socioeconômicos. MÉTODOS: Foram analisadas amostras de fezes de crianças com idade entre 6 e 10 anos sem sintomas gastrointestinais ou uso recente de antimicrobianos. O primeiro grupo foi constituído por 86 crianças, moradoras em uma favela localizada no município de Osasco (SP). O segundo grupo foi constituído por 36 crianças matriculadas em uma escola particular da mesma cidade. O estado nutricional foi avaliado usando o índice de massa corporal (IMC) de acordo com os valores de referência do National Center for Health Statistics (NCHS). O isolamento das colônias foi realizado em meios de cultura específicos em anaerobiose, durante 48 e 72 horas a 37 °C. A determinação do número foi feita pelo método da contagem em placa. RESULTADOS: A mediana de lactobacilos (1,125 x 10(9) unidades formadoras de colônia, UFC/g) e bifidobactérias (1,675 x 10(9) UFC/g) na escola particular foi superior (p < 0,001) ao do grupo da favela: 0,250 x 10(9) e 0,350 x 10(9) UFC/g, respectivamente. No grupo da favela, crianças com escore z de IMC < -1,0 desvio padrão (n = 28) apresentaram menor mediana (p < 0,05) de lactobacilos (0,100 x 10(9) UFC/g) e bifidobactérias (0,095 x 10(9) UFC/g) em relação às crianças com IMC > -1,0 desvio padrão (n = 57): 0,350 x 10(9) e 0,420 x 10(9) UFC/g, respectivamente. CONCLUSÃO: A microbiota de crianças escolares que moram em condições ambientais desfavoráveis apresenta menor número de colônias de lactobacilos e bifidobactérias nas fezes, especialmente naquelas com menores valores do IMC.

OBJECTIVE: To determine the number of lactobacillus and bifidobacterium colonies in the feces of schoolchildren from two different socioeconomic levels. METHODS: We analyzed fecal samples of children aged 6 to 10 years without gastrointestinal symptoms or recent use of antimicrobials. The first group included 86 children living in a favela in the city of Osasco, state of São Paulo, southeastern Brazil. The second group included 36 children attending a private school in the same city. Body mass index (BMI) was used to assess nutritional status according to the reference values of the National Center for Health Statistics (NCHS). Specific anaerobic culture media were used for isolation of colonies for 48 and 72 hours at 37 °C. The number of colonies was determined using the plate-counting method. RESULTS: The mean lactobacillus (1.125 x 10(9) colony-forming units, CFU/g) and bifidobacterium (1.675 x 10(9) CFU/g) counts in the private school group were higher (p < 0.001) than those in the favela group: 0.250 x 10(9) and 0.350 x 10(9) CFU/g, respectively. In the favela group, children with BMI z score < -1.0 standard deviation (SD) (n = 28) showed lower mean (p < 0.05) lactobacillus (0.100 x 10(9) CFU/g) and bifidobacterium (0.095 x 10(9) CFU/g) counts than the children with BMI > -1.0 SD (n = 57): 0.350 x 10(9) and 0.420 x 10(9) CFU/g, respectively. CONCLUSION: The microbiota of schoolchildren living in unfavorable environmental conditions shows lower numbers of fecal lactobacillus and bifidobacterium colonies, especially in children with lower BMI values.

A quantitative and relative increase in intestinal bacteroides in allergic infants in rural Japan.

Recent studies have suggested that intestinal microbiota play a substantial role in the development of allergic diseases during infancy. We analyzed fecal microbiota in 18 Japanese infants with or without allergy at 6 months and 2 years of age using a cell culture technique. Allergy determination was based on doctor-diagnosed allergic diseases and skin prick tests. There were no differences between 9 allergic and 9 non-allergic infants at 6 months of age in the frequencies or counts of 13 genera and yeast-like organisms. Bifidobacterium was dominant in all infants irrespective of allergy status. At 2 years of age, 8 infants were non-allergic and 10 infants were allergic. Allergic infants at 2 years of age had higher counts of Bacteroides and higher ratios of Bacteroides to Bifidobacterium than non-allergic infants. Despite the small population size used in this study, the results support a significant role of Bacteroides in the pathogenesis of allergy during infancy.

Evaluation of culture media for counts of Bifidobacterium animalis subsp. lactis Bb 12in yoghurt after refrigerated storage / Avaliação de meios de cultura para contagem de Bifidobacterium animalis subsp. lactis Bb 12em iogurte após a estocagem refrigerada

The agar RCPB pH5 has been considered a good alternative for counts of Bifidobacterium in yoghurt. However, during the refrigerated storage of yoghurt it is extremely difficult to count this microorganism due to the size of the colonies, which are so small they require the aid of a stereoscope to count them. Another agar, MRS-LP, has been also recommended for counts of Bifidobacterium in the presence of yoghurt bacteria. This study evaluated the supplementation of RCPB pH5 agar with dehydrated liver extract and the salts KH2PO4, K2HPO4, FeSO(4)7H2O, MnSO4H2O and MgSO(4)7H2O, aiming at improving the differentiation of Bifidobacterium in yoghurt after refrigerated storage, and also evaluated the selective count of Bifidobacterium in yoghurt using the agar MRS-LP. The agar MRS-LP presented the same cell recovery as non-fortified RCPB pH5 agar, used as a standard medium, thus being considered a good option for counts of Bifidobacterium in yoghurt. The fortified RCPB pH5 also presented the same recovery as the standard RCPB pH5 medium, however, the addition of dehydrated liver extract to the RCPB pH5 agar considerably increased the size of the Bifidobacterium colonies after refrigerated storage, making differentiation of the colonies much easier and reliable when compared to the standard non-fortified RPCP pH5. The addition of the salts (KH2PO4, K2HPO4, FeSO(4)7H2O, MnSO4H2O and MgSO(4)7H2O) had no influence on the performance of the RCPB pH5 agar.

O meio RCPB pH5 tem sido considerado uma boa opção para a contagem de Bifidobacterium em iogurte. Entretanto, durante a estocagem refrigerada do iogurte é extremante difícil a contagem deste microrganismo devido ao pequeno diâmetro desenvolvido pelas colônias de Bifidobacterium neste meio, sendo que a sua contagem somente se torna possível com o auxílio de um estereoscópio. Outro meio, MRS-LP, também tem sido recomendado para a contagem de Bifidobaterium em iogurte. Este estudo avaliou a suplementação do meio RCPB pH5 com extrato de fígado desidratado e com os sais KH2PO4, K2HPO4, FeSO(4)7H2O, MnSO4H2O e MgSO(4)7H2O, visando melhorar a diferenciação de Bifidobacterium em iogurte durante a estocagem refrigerada e também avaliou a contagem seletiva de Bifidobacterium em iogurte usando o meio MRS-LP. O meio MRS-LP apresentou a mesma recuperação de células que o meio RCPB pH5, usado como padrão, após 30 dias de estocagem refrigerada do iogurte, sendo considerado uma boa opção para a contagem de Bifidobacterium em iogurtes durante a estocagem refrigerada. O meio RCPB pH5 fortificado também apresentou a mesma recuperação de células de Bifidobacterium que o meio padrão RCPB pH5; entretanto, a adição de extrato de fígado desidratado aumentou consideravelmente o diâmetro das colônias de Bifidobacterium, tornando a diferenciação destas bastante fácil e confiável quando comparadas à sua diferenciação no meio RCPB pH5 sem a fortificação. A adição dos sais (KH2PO4, K2HPO4, FeSO(4)7H2O, MnSO4H2O e MgSO(4)7H2O) não exerceu influência no desempenho do meio RCPB pH5.

Regulación de la microbiota intestinal en voluntarios sanos mediante el consumo de un producto con el probiotico Lactobacillus johnsonii La1 / Regulation of the intestinal microbiota of healthy volunteers through the intake of the probiotic lactobacillus johnsonii la1

A basic mechanism implicated in the human health-promoting properties of probiotics is their ability to maintain the homeostasis of the intestinal microbiota. This study evaluates how the ingestion of different amounts of the probiotic Lactobacillus johnsonii La1 (La1) influences the main bacterial populations of the fecal microbiota. Eight asymptomatic volunteers participated in the study. After a basal period, they ingested 100 mL of a product containing 10(8) La1/mL during the first week, 200 mL during the second week and 500 ml during the third week. Fecal samples were obtained at the end of each period and during the 2 weeks post-ingestion. Lactobacilli were determined by culture on MRS agar and La1 colonies were confirmed by ERIC-PCR. The main populations of fecal bacteria were identified by fluorescent probes and flow cytometry. At baseline, 18.3 percent of the total fluorescent bacteria were F. praunitzii, 13.2 percent Bacteroides, 2.05 percent Bifidobacterium and 0.95 percent Lactobacillus. Fecal excretion of La1 increased during the ingestion period but it was cleared from the stools of the volunteers 2 weeks later. La1 intake increased the populations of Lactobacillus (p=0.056) and Bifidobacterium (p=0.067), which are considered as beneficial for the host, while it decreased those of F. prausnitzii (p=0.005) a potentially pathogenic microorganism. These bacterial populations returned to their baseline levels during the post-ingestion period. The regular intake of a La1-containing product beneficially affects the homeostasis of the human fecal microbiota probably contributing to the health-promoting effects of this probiotic.

Uno de los principales mecanismos implicados en las propiedades saludables de los probióticos es su capacidad de mantener la homeostasis de la microbiota intestinal. Este estudio evalúa cómo el consumo de distintas cantidades del probiótico Lactobacillus johnsonii La1 (La1) contribuye en la modulación de las principales poblaciones de la microbiota fecal. Ocho voluntarios asintomáticos participaron en el estudio. Después de un periodo basal, consumieron 100 mL de un producto que contenía 10(8) La1/mL durante la primera semana, 200 mL durante la segunda semana y 500 mL durante la tercera semana. Se obtuvieron muestras de deposición al final de cada uno de estos períodos y luego a los 7 y 14 días de haber terminado el consumo del producto. Las cantidades de lactobacilos excretados fueron determinadas por cultivo en agar MRS y las colonias de La1 fueron confirmadas por ERIC-PCR. Algunas de las principales poblaciones de bacterias fecales fueron evaluadas por hibridación in situ con sondas fluorescentes (FISH) y citometría de flujo. A nivel basal, 18.3 por ciento del número total de bacterias fluorescentes detectadas eran F. praunitzii,13.2 por ciento Bacteroides, 2.05 por ciento Bifidobacterium y 0.95 por ciento Lactobacillus. La excreción fecal de La1 aumentó durante el período de consumo pero desapareció después de 14 días de haber terminado el período de ingestión. El consumo de La1 aumentó las poblaciones de Lactobacillus (p=0.056) y Bifidobacterium (p=0.067) que son consideradas como beneficiosas para el huésped mientras que disminuyó aquella de F. prausnitzii (p=0.005), un microorganismo potencialmente patogénico. Las poblaciones bacterianas afectadas volvieron a sus niveles basales durante el periodo post-ingestión. Estos resultados indican que el consumo regular de La1 modula la homeostasis de la microbiota intestinal, lo cual contribuye probablemente a los efectos beneficiosos de este probiótico sobre la salud.

[Identification of Bifidobacterium strains isolated from fecal samples of some Iranian subjects using 16 SrRNA gene sequence analysis and PCR-based gene specific primers]

For the first time in Iran 40 strains of Bifidobacterium were isolated from feces of Iranian subjects. By using phenotypic tests, 18 isolates were identified as Bifidobacterium longum, 10 as Bifidobacterium bifidum and one as Bifidobacterium catenolatum. In order to validate these results and also to identify other isolates that had not been identified by phenotypic tests, two methods of PCR with genus-specific primers of Bif164f and Bif601r and 16SrRNA gene sequence analysis were applied. Results of PCR confirmed the obtained phenotypic identifications. Moreover by this method the 8 remaining strains were identified as Bifidobacterium species. Using sequencing 16 SrRNA gene, 5 B. longum strains were identified that had different fermentation pattern from B. longum. Some new ribose negative Bifidobacterium longum strains were also identified. The obtained results present new strains of Bifidobacterium longum

Antimicrobial activity of bifidobacteria isolated from baby faeces

Bifidobacteria strains, isolated from baby faeces, were examined for their antibacterial activity by deferred agar spot [DAS] test. A number of thirteen isolates were investigated using test strains from two different genera [Salmonella typhimurium and Escherichia coli]. The isolates were morphologically characterized and molecularly identified via polymerase chain reaction [PCR]. The different random amplified polymorphic DNA [RAPD] patterns were able to identify three groups of Bifidobacteria. All isolates showed an inhibition zone diameter with a mean of 10 mm against S. typhimurium and 6 mm against E. coli