RESUMEN
Conjugated Linoleic Acid (CLA), a fatty acid with high nutraceutical value is produced in rumen by resident bacterial species, especially Butyrivibrio spp. The present study was undertaken to examine the diversity of indigenous Butyrivibrio spp. from rumen liquor of Indian ruminants. The isolates were screened for their CLA production capability at different level of linoleic acid (LA) (0, 200, 400, 600, 800 µg/ml) at different time intervals (0, 2, 4, 6, 12, and 24 h). A total of more than 300 anaerobic cultures were isolated and 31 of them were identified as Butyrivibrio spp. based on morphological, biochemical and molecular characterization. Further, molecular characterization revealed that a large portion (67.7 %) of isolated Butyrivibrio belonged to Butyrivibrio fibrisolvens (B. fibrisolvens) species which is considered to be the most active bacteria amongst the rumen bacteria populace in terms of CLA production. Bacterial isolate VIII (strain 4a) showed highest CLA production ability (140.77 µg/ml) when incubated at 200 µg/ml LA for 2 h, which is 240 % higher than the isolate XXVII, Butyrivibrio proteoclasticus (B. proteoclasticus) showing lowest CLA production (57.28 µg/ml) amongst the screened isolates. It was evident from the observations recorded during the course of experiments that CLA production ability is strain specific and thus did not follow a single pattern. CLA production also varied with time of incubation and concentration of free linoleic acid supplemented in the growth medium. The results of these findings put forward a strain that is high CLA producer and can be further exploited as an additive for enhancing meat and milk quality in ruminants.
RESUMEN
BACKGROUND: Cow milk allergy is the most common food allergy in children. So far, no effective treatment is available to prevent or cure food allergy. This study investigated whether orally administrated probiotics could suppress sensitisation in whey proteins (WP)-induced allergy mouse model. Two types of probiotic Dahi were prepared by co-culturing Dahi bacteria (Lactococcus lactis ssp. cremoris NCDC-86 and Lactococcus lactis ssp. lactis biovar diacetylactis NCDC-60) along with selected strain of Lactobacillus acidophilus LaVK2 and Bifidobacterium bifidum BbVK3. Mice were fed with probiotic Dahi (La-Dahi and LaBb-Dahi) from 7 days before sensitisation with WP, respectively, in addition to milk protein-free basal diet, and control group received no supplements. RESULTS: Feeding of probiotic Dahi suppressed the elevation of whey proteins-specific IgE and IgG response of WP-sensitised mice. In addition, sIgA levels were significantly (P < 0.001) increased in intestinal fluid collected from mice fed with La-Dahi. Production of T helper (Th)-1 cell-specific cytokines, i.e. interferon-γ (IFN-γ), interleukin (IL)-12, and IL-10 increased, while Th2-specific cytokines, i.e. IL-4 decreased in the supernatant of cultured splenocytes collected from mice fed with probiotic Dahi as compared to the other groups. Moreover, the splenic mRNA levels of IFN-γ, interleukin-10 were found to be significantly increased, while that of IL-4 decreased significantly in La-Dahi groups, as compared to control groups. CONCLUSION: Results of the present study indicate that probiotic Dahi skewed Th2-specific immune response towards Th1-specific response and suppressed IgE in serum. Collectively, this study shows the potential use of probiotics intervention in reducing the allergic response to whey proteins in mice. © 2015 Society of Chemical Industry.