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1.
J Periodontal Res ; 58(5): 1006-1019, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37482954

RESUMO

OBJECTIVE: To determine whether Bifidobacterium animalis subspecies lactis HN019 (B. lactis HN019) can reduce the sequelae of experimental periodontitis (EP) in rats modulating systemic parameters. BACKGROUND: This study evaluated the effects of probiotic therapy (PROB) in the prevention of local and systemic damage resulting from EP. METHODS: Forty-eight rats were allocated into four groups: C (control), PROB, EP, and EP-PROB. PROB (1 × 1010 CFU/mL) administration lasted 8 weeks and PE was induced on the 7th week by placing ligature on the animals' lower first molars. All animals were euthanized in the 9th week of the experiment. Biomolecular analyses, RT-PCR, and histomorphometric analyses were performed. The data obtained were analyzed statistically (ANOVA, Tukey, p < .05). RESULTS: The EP group had higher dyslipidemia when compared to the C group, as well as higher levels of insulin resistance, proteinuria levels, percentages of systolic blood pressure, percentage of fatty hepatocytes in the liver, and expression of adipokines was up-regulated (LEPR, NAMPT, and FABP4). All these parameters (except insulin resistance, systolic blood pressure, LEPR and FABP4 gene expression) were reduced in the EP-PROB group when compared to the EP group. The EP group had lower villus height and crypt depth, as well as a greater reduction in Bacteroidetes and a greater increase in Firmicutes when compared to the EP-PROB group. Greater alveolar bone loss was observed in the EP group when compared to the EP-PROB group. CONCLUSION: Bifidobacterium lactis HN019 can reduce the sequelae of EP in rats modulating intestinal parameters, attenuating expression of lipogenic genes and hepatic steatosis.


Assuntos
Bifidobacterium animalis , Fígado Gorduroso , Resistência à Insulina , Periodontite , Probióticos , Ratos , Animais , Bifidobacterium animalis/fisiologia , Probióticos/uso terapêutico , Periodontite/prevenção & controle , Mucosa Intestinal
2.
Clin Oral Investig ; 27(1): 387-398, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36305963

RESUMO

OBJECTIVES: This double-blind, randomized, placebo-controlled clinical trial evaluated the adjuvant effects of Bifidobacterium lactis HN019 on the treatment of plaque-induced generalized gingivitis. MATERIALS AND METHODS: Sixty patients were submitted to professional supragingival scaling and prophylaxis. They were randomly assigned to test (probiotic lozenges containing B. lactis HN019, n = 30) or control (placebo lozenges, n = 30) groups. Lozenges were consumed twice a day for 8 weeks. Bleeding on probing (BoP), Gingival Index (GI), Plaque Index (PI), probing depth (PD), and clinical attachment level (CAL) were evaluated at baseline and after 2 and 8 weeks. Gingival crevicular fluid (GCF) was collected at baseline and at 8 weeks for analysis of the inflammatory mediators IL-1ß, IL-1α, IL-8, MCP-1, and MIP-1ß. Data were statistically analyzed (p < 0.05). RESULTS: After 8 weeks, both groups showed reduction in the percentage of PI, with no significant difference between groups (p = 0.7423). The test group presented a lower percentage of BoP and a higher percentage of sites with GI ≤ 1 when compared with the control group at the end of the study (p < 0.0001). At 8 weeks, the test group had a greater number of patients without generalized gingivitis than the control group (20 and 11 patients, respectively; p < 0.05). The test group presented significantly lower levels of IL-1α, IL-1ß, and MCP-1 in GCF than the control group at the end of the study (p < 0.05). CONCLUSION: The adjunct use of B. lactis HN019 promotes additional clinical and immunological benefits in the treatment of generalized gingivitis. CLINICAL RELEVANCE: B. lactis HN019 can be an efficient and side-effect-free adjunct strategy in the treatment of generalized gingivitis.


Assuntos
Bifidobacterium animalis , Placa Dentária , Gengivite , Placa Aterosclerótica , Humanos , Gengivite/terapia , Raspagem Dentária , Placa Dentária/terapia , Placa Dentária/microbiologia , Administração Oral , Líquido do Sulco Gengival
3.
Nutr Rev ; 80(6): 1619-1633, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-34918142

RESUMO

CONTEXT: The effects of probiotics on gastrointestinal (GI) symptoms have been increasingly investigated, particularly that of Bifidobacterium animalis. Clinical trials so far have shown differing evidence regarding these effects in healthy adults. OBJECTIVE: To synthesize the published evidence on the effects of B. animalis subspecies lactis on GI symptoms (GIS) in healthy adults. DATA SOURCE: A search of the Medline, Embase, Lilacs, Scopus, Web of Science, ProQuest, and Google Scholar databases was conducted for reports on randomized controlled trials published up to October 2021. DATA EXTRACTION: Population characteristics and data on colonic transit time (CTT), stool consistency, defecation frequency, abdominal pain, bloating, flatulence, volunteer compliance, and adverse events were extracted. A random-effects model was used to estimate the effect of probiotic treatment on these variables. DATA SYNTHESIS: In total, 1551 studies were identified, of which 14 were included in the qualitative synthesis and 13 in the meta-analysis. Overall, probiotic supplementation increased defecation frequency (standardized mean difference [SMD], 0.26; 95%CI, 0.13-0.39). Subgroup analysis revealed a decrease in CTT (SMD, -0.34; 95%CI, -0.62 to -0.07) in short-term treatment (≤14 d) and an improvement in stool consistency (SMD, 0.76; 95%CI, 0.44-1.08) in individuals without GIS. No improvement in abdominal pain and bloating was found. CONCLUSIONS: B. animalis subspecies lactis supplementation may increase defecation frequency and, in short-term treatment, may reduce CTT in healthy adults and improve stool consistency in individuals without GIS. More high-quality randomized controlled trials are needed to develop a clinical protocol for the use of this strain to improve these symptoms. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42020154060.


Assuntos
Bifidobacterium animalis , Gastroenteropatias , Probióticos , Dor Abdominal/prevenção & controle , Adulto , Gastroenteropatias/prevenção & controle , Humanos , Probióticos/uso terapêutico
4.
Benef Microbes ; 12(5): 493-501, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34463193

RESUMO

Indole-3 carbinol (I3C) has shown dual effects on the promotion and progression stages of colon carcinogenesis while synbiotics (Syn) have exerted anti-carcinogenic activities in most rodent studies. This study aimed to investigate the effects of I3C given alone or together with a Syn intervention on 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis. All animals were given four subcutaneous DMH injections (4×40 mg/kg bodyweight, twice a week for two weeks) and then received either basal diet (G1), basal diet containing I3C (1g/kg chow) (G2) or basal diet containing I3C+Syn (I3C + inulin 50g/kg chow + Bifidobacterium lactis BB-12®), 2.5×1010 cfu/g of basal diet), (G3) for 21 weeks. Dietary I3C (G2) significantly increased tumour volume and cell proliferation when compared to the DMH control group (G1). Syn intervention (G3) significantly reduced tumour volume and cell proliferation when compared to I3C (G2). The colon tumours found were classified into well-differentiated tubular adenomas or adenocarcinomas. Dietary I3C or I3C+Syn did not significantly affect the incidence and the multiplicity of tumours in comparison with the DMH control group. Furthermore, Syn intervention (G3) increased Gstm1 and reduced Mapk9 gene expression in colonic tumours. The findings of the present study show that the dietary I3C shows a weak promoting activity, while the combination with Syn ameliorates I3C effects.


Assuntos
Carcinogênese , Neoplasias do Colo , Indóis , Simbióticos , Animais , Carcinogênese/efeitos dos fármacos , Neoplasias do Colo/prevenção & controle , Indóis/efeitos adversos
5.
Food Res Int ; 143: 110292, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33992391

RESUMO

Infant́s gut microbiota can be modulated by many factors, including mode of delivery, feeding regime, maternal diet/weight and probiotic and prebiotic consumption. The gut microbiota in dysbiosis has been associated with innumerous diseases. In this sense, early childhood intestinal microbiome modulation can be a strategy for disease prevention. This study had the purpose to evaluate the effect of an infant cereal with probiotic (Bifidobacterium animalis ssp. lactis BB-12®) on infant́s intestinal microbiota using SHIME®, which simulates human gastrointestinal conditions. The ascending colon was inoculated with fecal microbiota from three children (2-3 years old). NH4+, short chain fatty acids (SCFASs) and microbiota composition were determined by selective ion electrode, GC/MS and 16S sequencing, respectively. After treatment, butyric acid production increased (p < 0.05) 52% and a decrease in NH4+ production was observed (p < 0.01). The treatment stimulated an increase (p < 0.01) of Lactobacillaceae families, more precisely L. gasseri and L. kefiri. L. gasseri has been associated with the prevention of allergic rhinitis in children and L. kefiri in the prevention of obesity. Thus, infant cereal with BB-12® is able to stimulate the growth of L. gasseri and L. kefiri in a beneficial way, reducing NH4+ and increasing the production of SCFAs, especially butyric acid, in SHIME®.


Assuntos
Bifidobacterium animalis , Microbioma Gastrointestinal , Microbiota , Probióticos , Criança , Pré-Escolar , Grão Comestível , Humanos , Lactente
6.
J Clin Periodontol ; 45(10): 1198-1210, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30076613

RESUMO

AIM: This randomized placebo-controlled clinical trial evaluated the effect of Bifidobacterium animalis subsp. lactis (B. lactis) HN019-containing probiotic lozenges as adjuvant to scaling and root planing (SRP) in patients with generalized chronic periodontitis. MATERIALS AND METHODS: Forty-one chronic periodontitis patients were recruited and monitored clinically, immunologically, and microbiologically at baseline (before SRP) and 30 and 90 days after SRP. All patients were randomly assigned to a Test (SRP + Probiotic, n = 20) or Control (SRP + Placebo, n = 21) group. The probiotic lozenges were used twice a day for 30 days. The data were statistically analysed. RESULTS: The Test group presented a decrease in probing pocket depth and a clinical attachment gain significantly higher than those of the Control group at 90 days. The Test group also demonstrated significantly fewer periodontal pathogens of red and orange complexes, as well as lower proinflammatory cytokine levels when compared to the Control group. Only the Test group showed an increase in the number of B. lactis HN019 DNA copies on subgingival biofilm at 30 and 90 days. CONCLUSION: The use of B. lactis HN019 as an adjunct to SRP promotes additional clinical, microbiological, and immunological benefits in the treatment of chronic periodontitis (NCT03408548).


Assuntos
Periodontite Crônica , Probióticos , Bifidobacterium , Raspagem Dentária , Humanos , Aplainamento Radicular
7.
J Food Sci ; 82(10): 2462-2470, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28892139

RESUMO

The aim of this study is to evaluate the influence of the technological processing on the functionality of the human breast milk probiotic strain Bifidobacterium lactis INL1. In vitro antagonistic activity of B. lactis INL1 was detected for Gram-positive and Gram-negative pathogens. B. lactis INL1 was administered to mice as fresh (F), frozen (Z), spray-dried (S), or lyophilized (L) culture. Immune parameters (IgA, IL-10, and IFN-γ) were determined and histological analysis was performed to assess functionality and protection capacity against Salmonella. In BALB/c mice, F and S cultures induced an increase in the number of IgA-producing cells in the small intestine and IL-10 levels were increased for L culture in the large intestine. In Swiss mice, B. lactis INL1 increased secretory-IgA levels in the small intestine before and after Salmonella infection, both as F or dehydrated culture. Also, an attenuation of damage in the intestinal epithelium and less inflammatory infiltrates were observed in animals that received F and S cultures, whereas in liver only F showed some effect. The anti-inflammatory effect was confirmed in both tissues by myeloperoxidase activity and by IFN-γ levels in the intestinal content. B. lactis INL1 showed inhibitory activity against pathogens and confirmed its probiotic potential in animal models. Technological processing of the probiotic strain affected its functionality. PRACTICAL APPLICATION: This work provides evidence about the influence of technology on the functionality of probiotics, which may help probiotics and functional food manufacturers to take processing into consideration when assessing the functionality of new strains.


Assuntos
Bifidobacterium/isolamento & purificação , Leite Humano/microbiologia , Probióticos/administração & dosagem , Infecções por Salmonella/tratamento farmacológico , Animais , Bifidobacterium/genética , Bifidobacterium/metabolismo , Feminino , Humanos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Intestino Delgado/imunologia , Intestino Delgado/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Probióticos/química , Salmonella/efeitos dos fármacos , Salmonella/fisiologia , Infecções por Salmonella/genética , Infecções por Salmonella/imunologia , Infecções por Salmonella/microbiologia
8.
Nutrition ; 32(6): 716-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27126957

RESUMO

OBJECTIVE: Human studies have shown the beneficial effects of probiotic microorganisms on the parameters of metabolic syndrome (MetS) and other cardiovascular risks, but to our knowledge the effect of Bifidobacterium lactis has not yet been reported. The aim of this study was to evaluate the effect of consumption of milk containing the probiotic B. lactis HN019 on the classical parameters of MetS and other related cardiovascular risk factors. METHODS: Fifty-one patients with MetS were selected and divided into a control group (n = 25) and a probiotic group (n = 26). The probiotic group consumed fermented milk with probiotics over the course of 45 d. The effects of B. lactis on lipid profile, glucose metabolism, and proinflammatory cytokines (tumor necrosis factor-α and interleukin-6) were assessed in blood samples of the individuals at the baseline and after 45 d. RESULTS: Daily ingestion of 80 mL fermented milk with 2.72 × 10(10) colony-forming units of B. lactis HN019 showed significant reduction in body mass index (P = 0.017), total cholesterol (P = 0.009), and low-density lipoprotein (P = 0.008) compared with baseline and control group values. Furthermore, a significant decrease in tumor necrosis factor-α (P = 0.033) and interleukin-6 (P = 0.044) proinflammatory cytokines was observed. CONCLUSION: These data showed potential effects of B. lactis HN019 in reducing obesity, blood lipids, and some inflammatory markers, which may reduce cardiovascular risk in patients with MetS.


Assuntos
Bifidobacterium , Citocinas/sangue , Lipídeos/sangue , Síndrome Metabólica/sangue , Síndrome Metabólica/dietoterapia , Probióticos/farmacologia , Adolescente , Adulto , Citocinas/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
J Dairy Res ; 82(3): 350-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25850555

RESUMO

Bacteriocins are natural compounds used as food biopreservatives instead of chemical preservatives. Bifidobacterium animalis subsp. lactis (Bifid. lactis) was shown to produce a bacteriocin-like inhibitory substance (BLIS) able to inhibit the growth of Listeria monocytogenes selected as an indicator microorganism. To enhance this production by the strain Bifid. lactis BL 04, skim milk (SM) was used as a fermentation medium either in the presence or in the absence of yeast extract, Tween 80 or inulin as stimulating additives, and the results in terms of bacterial growth and BLIS production were compared with those obtained in a traditional high cost complex medium such as Man, Rogosa and Sharpe (MRS). To this purpose, all the cultivations were carried out in flasks at 200 rpm under anaerobic conditions ensured by a nitrogen flowrate of 1.0 L/min for 48 h, and BLIS production was quantified by means of a modified agar diffusion assay at low values of both temperature and concentration of List. monocytogenes. Although all these ingredients were shown to exert positive influence on BLIS production in both media, yeast extract and SM were by far the best ingredient and the best medium, respectively, allowing for a BLIS production at the late exponential phase of 2000 AU/ml.


Assuntos
Bacteriocinas/biossíntese , Bifidobacterium/metabolismo , Leite/microbiologia , Animais , Bifidobacterium/crescimento & desenvolvimento , Aditivos Alimentares , Microbiologia de Alimentos , Inulina , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Leite/química , Polissorbatos , Leveduras
10.
Sci. agric ; 71(3): 204-211, Mai-Jun. 2014. graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1497411

RESUMO

Probiotics are live microorganisms that confer a health benefit on the host by improving the intestinal microbial balance. We evaluated the viability of Lactobacillus acidophilus (La) and Bifidobacterium lactis (Bl) probiotics and their effects on the technology and sensorial characteristics of fermented sausage. The presence of probiotic cultures reduced water activity and promoted faster pH reduction in the salamis, which presented pH values between 4.71 and 5.23 and water activity between 0.84 and 0.89. Lactic acid content ranged between 0.19 and 0.29 g, and the samples lost up to 35 % of their weight during ripening. As regards color, no differences were found between the probiotic salamis and the control, presenting an overall mean of 40.85 for L* (lightness), 14.48 for a* (redness) and 6.46 for b* (yellowness). High consumer acceptance was observed for the probiotic salamis, which showed an average acceptance of approximately 7.0 on a nine-point hedonic scale for all attributes evaluated, with no differences (p 0.05) when compared with the control. The performance of La was better, as the salamis treated with this microorganism presented less weight loss, better acceptance and greater purchase intention. Flavor and texture were the attributes that most influenced sensory acceptance. Salamis supplemented with probiotic cultures may be a viable option for the formulation of fermented sausages in the food industry.


Assuntos
Bifidobacterium animalis , Lactobacillus acidophilus , Probióticos , Produtos da Carne/análise , Produtos da Carne/microbiologia , Bovinos , Suínos
11.
Sci. Agric. ; 71(3): 204-211, Mai-Jun. 2014. graf, tab
Artigo em Inglês | VETINDEX | ID: vti-27995

RESUMO

Probiotics are live microorganisms that confer a health benefit on the host by improving the intestinal microbial balance. We evaluated the viability of Lactobacillus acidophilus (La) and Bifidobacterium lactis (Bl) probiotics and their effects on the technology and sensorial characteristics of fermented sausage. The presence of probiotic cultures reduced water activity and promoted faster pH reduction in the salamis, which presented pH values between 4.71 and 5.23 and water activity between 0.84 and 0.89. Lactic acid content ranged between 0.19 and 0.29 g, and the samples lost up to 35 % of their weight during ripening. As regards color, no differences were found between the probiotic salamis and the control, presenting an overall mean of 40.85 for L* (lightness), 14.48 for a* (redness) and 6.46 for b* (yellowness). High consumer acceptance was observed for the probiotic salamis, which showed an average acceptance of approximately 7.0 on a nine-point hedonic scale for all attributes evaluated, with no differences (p 0.05) when compared with the control. The performance of La was better, as the salamis treated with this microorganism presented less weight loss, better acceptance and greater purchase intention. Flavor and texture were the attributes that most influenced sensory acceptance. Salamis supplemented with probiotic cultures may be a viable option for the formulation of fermented sausages in the food industry.(AU)


Assuntos
Produtos da Carne/análise , Produtos da Carne/microbiologia , Probióticos , Lactobacillus acidophilus , Bifidobacterium animalis , Suínos , Bovinos
12.
Artigo em Inglês | VETINDEX | ID: vti-443822

RESUMO

This study evaluated the stability of Bifidobacterium lactis (Bb-12) and of Lactobacillus acidophilus (La-05) both free and immobilized in calcium alginate, in milk and in acidified milk (pH 5.0, 4.4 and 3.8). The stability of immobilized B. lactis in yoghurt (fermented to pH 4.2), during 28 days of refrigerated storage was also evaluated. The efficiency of two culture media (modified MRS agar and Reinforced Clostridial Agar plus Prussian Blue) for counting of B. lactis in yoghurt was determined. Lee's agar was used to count Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus when B. lactis were counted in the MRS medium. B. lactis and L. acidophilus in both free and immobilized forms presented satisfactory rates of survival in milk and acidified milk because the average reduction of the population was only one log cycle after 21 days of storage. The number of viable cells of immobilized B. lactis in yoghurt presented a gradual decline throughout the storage period, passing from 10(8) cfu/ml to no count after 28 days of storage. When the cultures were not in equilibrium just the selective medium was efficient in counting B. lactis in yoghurt. The results showed that both microorganisms can be added to milk and acidified milk, because their population was only slightly affected during storage. The presence of traditional culture of yoghurt seems to be harmful for survival of immobilized B. lactis and the immobilization in calcium alginate failed as an effective barrier to protect the cells in all analysed treatments.


Este trabalho avaliou a estabilidade de Bifidobacterium lactis (Bb-12) e de Lactobacillus acidophilus (La-05) nas formas livre e imobilizada em alginato de cálcio, em leite e leite acidificado (pHs 5.0, 4.4 e 3.8), e a estabilidade de B. lactis imobilizado em iogurte (fermentado até pH 4.2), durante 28 dias de estocagem refrigerada. Também foi estudada a eficiência de dois meios de cultura (ágar MRS modificado e Reinforced Clostridial Agar, acrescido de Prussian Blue) para enumerar B. lactis em iogurte. Ágar Lee foi usado para enumeração de Streptococcus thermophilus e Lactobacillus delbrueckii ssp. bulgaricus quando B. lactis era enumerado no meio MRS. Ambos os microrganismos, nas formas livre e imobilizada, apresentaram uma taxa de sobrevivência adequada nos leites acidificados, uma vez que houve redução de apenas um ciclo log, após 21 dias de estocagem refrigerada. O número de células viáveis de B. lactis imobilizado mostrou um declínio gradual durante o período de armazenamento do iogurte, passando de 10(8) ufc/ml até não ter mais contagem na diluição 10-1. Quando as culturas não estavam em equilíbrio, o meio MRS modificado foi mais eficiente para a contagem de B. lactis em iogurte. Em vista destes resultados pode-se concluir que ambos os microrganismos podem ser incorporados em leite e leite acidificados, haja visto que a redução na população foi pequena durante o período de armazenagem estudado. A presença da cultura tradicional de iogurte parece ter afetado negativamente a sobrevivência de B. lactis e a imobilização não proveu proteção às células, em nenhum dos tratamentos estudados.

13.
Braz. j. microbiol ; Braz. j. microbiol;35(1)2004.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469536

RESUMO

This study evaluated the stability of Bifidobacterium lactis (Bb-12) and of Lactobacillus acidophilus (La-05) both free and immobilized in calcium alginate, in milk and in acidified milk (pH 5.0, 4.4 and 3.8). The stability of immobilized B. lactis in yoghurt (fermented to pH 4.2), during 28 days of refrigerated storage was also evaluated. The efficiency of two culture media (modified MRS agar and Reinforced Clostridial Agar plus Prussian Blue) for counting of B. lactis in yoghurt was determined. Lee's agar was used to count Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus when B. lactis were counted in the MRS medium. B. lactis and L. acidophilus in both free and immobilized forms presented satisfactory rates of survival in milk and acidified milk because the average reduction of the population was only one log cycle after 21 days of storage. The number of viable cells of immobilized B. lactis in yoghurt presented a gradual decline throughout the storage period, passing from 10(8) cfu/ml to no count after 28 days of storage. When the cultures were not in equilibrium just the selective medium was efficient in counting B. lactis in yoghurt. The results showed that both microorganisms can be added to milk and acidified milk, because their population was only slightly affected during storage. The presence of traditional culture of yoghurt seems to be harmful for survival of immobilized B. lactis and the immobilization in calcium alginate failed as an effective barrier to protect the cells in all analysed treatments.


Este trabalho avaliou a estabilidade de Bifidobacterium lactis (Bb-12) e de Lactobacillus acidophilus (La-05) nas formas livre e imobilizada em alginato de cálcio, em leite e leite acidificado (pHs 5.0, 4.4 e 3.8), e a estabilidade de B. lactis imobilizado em iogurte (fermentado até pH 4.2), durante 28 dias de estocagem refrigerada. Também foi estudada a eficiência de dois meios de cultura (ágar MRS modificado e Reinforced Clostridial Agar, acrescido de Prussian Blue) para enumerar B. lactis em iogurte. Ágar Lee foi usado para enumeração de Streptococcus thermophilus e Lactobacillus delbrueckii ssp. bulgaricus quando B. lactis era enumerado no meio MRS. Ambos os microrganismos, nas formas livre e imobilizada, apresentaram uma taxa de sobrevivência adequada nos leites acidificados, uma vez que houve redução de apenas um ciclo log, após 21 dias de estocagem refrigerada. O número de células viáveis de B. lactis imobilizado mostrou um declínio gradual durante o período de armazenamento do iogurte, passando de 10(8) ufc/ml até não ter mais contagem na diluição 10-1. Quando as culturas não estavam em equilíbrio, o meio MRS modificado foi mais eficiente para a contagem de B. lactis em iogurte. Em vista destes resultados pode-se concluir que ambos os microrganismos podem ser incorporados em leite e leite acidificados, haja visto que a redução na população foi pequena durante o período de armazenagem estudado. A presença da cultura tradicional de iogurte parece ter afetado negativamente a sobrevivência de B. lactis e a imobilização não proveu proteção às células, em nenhum dos tratamentos estudados.

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