Effect of maternal probiotic intervention on HPA Axis, immunity and gut microbiota in a rat model of irritable bowel syndrome

Objective: To examine whether maternal probiotic intervention influences the alterations in the brain-immune-gut axis induced by neonatal maternal separation (MS) and/or restraint stress in adulthood (AS) in Wistar rats. Design: Dams had free access to drinking water supplemented with Bifidobacterium animalis subsp lactis BB-12® (3x109 CFU/mL) and Propionibacterium jensenii 702 (8.0x108 CFU/mL) from 10 days before conception until postnatal day (PND) 22 (weaning day), or to control ad lib water. Offspring were subjected to MS from PND 2 to 14 or left undisturbed. From PND 83 to 85, animals underwent 30 min/day AS, or were left undisturbed as controls. On PND 24 and 86, blood samples were collected for corticosterone, ACTH and IgA measurement. Colonic contents were analysed for the composition of microflora and luminal IgA levels. Results: Exposure to MS significantly increased ACTH levels and neonatal fecal counts of aerobic and anaerobic bacteria, E. coli, enterococci and clostridia, but reduced plasma IgA levels compared with non-MS animals. Animals exposed to AS exhibited significantly increased ACTH and corticosterone levels, decreased aerobic bacteria and bifidobacteria, and increased Bacteroides and E. coli counts compared to non-AS animals. MS coupled with AS induced significantly decreased anaerobes and clostridia compared with the non-stress adult controls. Maternal probiotic intervention significantly increased neonatal corticosterone levels which persisted until at least week 12 in females only, and also resulted in elevated adult ACTH levels and altered neonatal microflora comparable to that of MS. However, it improved plasma IgA responses, increased enterococci and clostridia in MS adults, increased luminal IgA levels, and restored anaerobes, bifidobacteria and E. coli to normal in adults. Conclusion: Maternal probiotic intervention induced activation of neonatal stress pathways and an imbalance in gut microflora. Importantly however, it improved the immune environment of stressed animals and protected, in part, against stress-induced disturbances in adult gut microflora

Effect of adult stress on faecal counts of aerobic bacteria and <i>Bacteroides</i>.

<p>Effect of exposure to stress in adulthood (week 12) on faecal counts of aerobic bacteria and Bacteroides (Log CFU/gr, least squares means+SE). The hollow bars represent animals exposed to no adult stress (NA): Aerobes NA (n = 72), <i>Bacteroides</i> NA (n = 67). The filled bars represent animals exposed to adult stress (AS): Aerobes AS (n = 75), <i>Bacteroides</i> AS (n = 75). An asterisk (*) indicates statistical significant difference (<i>p</i>≤0.05).</p

Lactic microflora present in Liqvan Ewes\u27 milk cheese

This study aimed to isolate and characterize Lactic Acid Bacteria (LAB) in Liqvan Ewes\u27 milk cheese. A total of 117 Lactic Acid Bacteria were isolated and identified phenotypically. They belonged to 4 genera and 17 species. The dominant LAB found in Liqvan cheese were from the genus Lactobacillus (75.21%) consisted of 70.08% facultatively heterofermentative and 5.12% obligately heterofermentative lactobacillus species. Other isolates were classified as Pediococci (5.12%), Enterococci (5.98%), and Leuconostocs (13.67%). Lb. paracasei subsp. paracasei was the predominant species accounted for 36.75%. Likewise, predominant species of each genus were Lb. paracasei subsp. paracasei, P. pentosaceus, E. faecalis, and Leu. lactis. The preponderance of isolates (86.32%) was referred to be as members of Non Starter Lactic Acid Bacteria (NSLAB)

Effect of maternal probiotic intake and stress on adult gut microflora.

<p>Effect of maternal probiotic intake, neonatal maternal separation (MS) and adult restraint stress (AS) on faecal counts of anaerobes, enterococci and clostridia (Log CFU/gr, least squares means+SE) in Wistar rats at week 12. Hollow bars represent no-stress control animals or those exposed to adult stress (AS): control vehicle (n = 11–19), AS vehicle (n = 18–20), control probiotic (n = 17), AS probiotic (n = 17). Filled bars represent MS or MS+AS animals: MS vehicle (n = 20), MS+AS vehicle (n = 20), MS probiotic (n = 18), MS+AS probiotic (n = 19). An asterisk (*) shows significant difference compared to non-stressed (NS-NA) animals in the vehicle subset (<i>p</i>≤0.05).</p

Maternal probiotic intervention and luminal IgA levels.

<p>Effect of maternal probiotic intervention on Ln-transformed faecal IgA concentrations (LnFIgA, least squares means+SE). Initial IgA data were expressed as µg/gr faeces. The figure presents aggregated data across test days (PND 24 and 86).The filled bar represents animals born to probiotic-treated dams (n = 101) and the hollow bar represents animals born to vehicle-treated dams (n = 113). An asterisk (*) indicates statistical significant difference (<i>p</i>≤0.05).</p

Growth of Salmonella on inoculated inhull pistachios during postharvest handling

Salmonella has been isolated from dried pistachios in both postharvest and retail surveys. The source of Salmonella in pistachios is unknown, but introduction is possible at points during production, harvest, and postharvest activities. To examine the behavior of Salmonella on pistachios during simulated postharvest conditions, early-, mid-, and late-season inhull pistachios were collected from two commercial processors over five different harvests. Pistachios were inoculated with cocktails of nalidixic acid– or rifampin-resistant Salmonella at 0.64 to 1.59 log CFU/g (low) or 2.73 to 3.27 or 4.29 to 4.31 log CFU/g (high) and were incubated for up to 30 h under commercially relevant conditions (23, 35, or 37°C and 50 or 90% relative humidity [RH]). Populations of Salmonella were measured by plating onto tryptic soy agar and CHROMagar Salmonella with added nalidixic acid or rifampin. Individual growth curves at the same temperature and RH differed significantly among different lots of pistachios. Except for a single late-season lot in which no significant growth was observed, Salmonella multiplied under all storage conditions. In the first 3 h after inoculation, insignificant (most cases) to small (0.41 to 0.67 log CFU/g) but significant (P\u3c 0.05) mean increases in Salmonella populations were measured; the mean predicted time to achieve maximum populations (5 to 8 log CFU/g) was 16 ±4 h. In paired samples, longer lag phases, lower growth rates, and lower maximum increases were observed with inoculated inhull pistachios incubated at 238C and 50% RH compared with 35 or 37°C and 90% RH. Similar growth curves were observed at the low and high inoculum levels; throughout the 30 h of incubation, Salmonella populations were consistently ~1 to 2 log CFU/g lower on pistachios inoculated at the low inoculum level. Managing the time between harvesting and hulling will reduce the potential for growth of Salmonella on pistachios during postharvest handling

Growth of salmonella and other foodborne pathogens on inoculated inshell pistachios during simulated delays between hulling and drying

During harvest, pistachios are hulled, separated in water into floater and sinker streams (in large part on the basis of nut density), and then dried before storage. Higher prevalence and levels of Salmonella were previously observed in floater pistachios, but contributing factors are unclear. To examine the behavior of pathogens on hulled pistachios during simulated drying delays, floater and sinker pistachios collected from commercial processors were inoculated at 1 or 3 log CFU/g with cocktails of Salmonella and in some cases Escherichia coli O157:H7 or Listeria monocytogenes and incubated for up to 30 h at 37°C and 90% relative humidity. Populations were measured by plating onto tryptic soy agar and appropriate selective agars. In most cases, no significant growth (P \u3e 0.05) of Salmonella was observed in the first 3 h after inoculation in hulled floaters and sinkers. Growth of Salmonella was greater on floater pistachios than on corresponding sinkers and on floater pistachios with ≥25% hull adhering to the shell surface than on corresponding floaters with \u3c25% adhering hull. Maximum Salmonella populations (2 to 7 log CFU/g) were ~2-log higher on floaters than on corresponding sinkers. The growth of E. coli O157:H7 and Salmonella on hulled pistachios was similar, but a longer lag time (approximately 11 h) and significantly lower maximum populations (4 versus 5 to 6 log CFU/g; P \u3e 0.05) were predicted for L. monocytogenes. Significant growth of pathogens on hulled pistachios is possible when delays between hulling and drying are longer than 3 h, and pathogen growth is enhanced in the presence of adhering hull material. HIGHLIGHTS • Foodborne pathogens multiplied on undried inshell pistachios. • Pathogen growth was greater when hull material was present. • Drying delays of \u3e 3 h led to significant increases in pathogen populations. • Managing drying delays will reduce the risk for growth of foodborne pathogens

Growth of Salmonella on inoculated inhull pistachios during postharvest handling

Salmonella has been isolated from dried pistachios in both postharvest and retail surveys. The source of Salmonella in pistachios is unknown, but introduction is possible at points during production, harvest, and postharvest activities. To examine the behavior of Salmonella on pistachios during simulated postharvest conditions, early-, mid-, and late-season inhull pistachios were collected from two commercial processors over five different harvests. Pistachios were inoculated with cocktails of nalidixic acid– or rifampin-resistant Salmonella at 0.64 to 1.59 log CFU/g (low) or 2.73 to 3.27 or 4.29 to 4.31 log CFU/g (high) and were incubated for up to 30 h under commercially relevant conditions (23, 35, or 37°C and 50 or 90% relative humidity [RH]). Populations of Salmonella were measured by plating onto tryptic soy agar and CHROMagar Salmonella with added nalidixic acid or rifampin. Individual growth curves at the same temperature and RH differed significantly among different lots of pistachios. Except for a single late-season lot in which no significant growth was observed, Salmonella multiplied under all storage conditions. In the first 3 h after inoculation, insignificant (most cases) to small (0.41 to 0.67 log CFU/g) but significant (P\u3c 0.05) mean increases in Salmonella populations were measured; the mean predicted time to achieve maximum populations (5 to 8 log CFU/g) was 16 ±4 h. In paired samples, longer lag phases, lower growth rates, and lower maximum increases were observed with inoculated inhull pistachios incubated at 238C and 50% RH compared with 35 or 37°C and 90% RH. Similar growth curves were observed at the low and high inoculum levels; throughout the 30 h of incubation, Salmonella populations were consistently ~1 to 2 log CFU/g lower on pistachios inoculated at the low inoculum level. Managing the time between harvesting and hulling will reduce the potential for growth of Salmonella on pistachios during postharvest handling

Effect of maternal probiotic intake and adult stress on bifidobacteria.

<p>Effect of maternal probiotic intake and adult restraint stress (AS) on faecal counts of bifidobacteria (Log CFU/gr, least squares means+SE) in Wistar rats at week 12. Hollow bars represent animals exposed to no adult stress (NA): NA vehicle (n = 33), NA probiotic (n = 35). Filled bars represent animals exposed to adult stress (AS): AS vehicle (n = 39), AS probiotic (n = 36). An asterisk (*) shows significant difference compared to non-stressed (NA) animals in the vehicle subset (<i>p</i>≤0.05).</p

Effect of maternal probiotic intervention, stress, and gender on plasma IgA levels.

<p><b>A</b>) Effect of sex on Ln-transformed plasma IgA concentrations (LnPIgA, least squares means+SE) in rats. The figure presents aggregated data across test days (PND 24 and 86). Initial IgA data were expressed as µg/mL plasma. The hollow bar represents males (n = 109) and the filled bar represents females (n = 117). An asterisk (*) indicates statistical significant difference (<i>p</i>≤0.05). <b>B</b>) Effect of maternal probiotic intake and neonatal maternal separation (MS) on Ln-transformed plasma IgA concentrations (LnPIgA, least squares means+SE) in rats at PND 24. The hollow bars represent animals exposed to no-MS (NS): NS vehicle (n = 15), NS probiotic (n = 19). The filled bars represent animals exposed to MS: MS vehicle (n = 19), MS probiotic (n = 20). An asterisk (*) indicates statistical significant difference relative to vehicle NS animals (<i>p</i>≤0.05). <b>C</b>) Effect of maternal probiotic intake, neonatal maternal separation (MS) and adult restraint stress (AS) on Ln-transformed plasma IgA concentrations (LnPIgA, least squares means+SE) in adult rats. Hollow bars represent no-stress control animals or those exposed to adult stress (AS): control vehicle (n = 21), AS vehicle (n = 20), control probiotic (n = 17), AS probiotic (n = 17). Filled bars represent MS or MS+AS animals: MS vehicle (n = 20), MS+AS vehicle (n = 20), MS probiotic (n = 18), MS+AS probiotic (n = 19). An asterisk (*) shows significant difference compared to control animals in the vehicle subset (<i>p</i>≤0.05).</p