Growth and Freeze-Drying Optimization of Bifidobacterium crudilactis

Bifidobacterium crudilactis FR62/b/3 belongs to a new population of bifidobacteria isolated from raw milk and raw milk cheese. The objective of this work was to study the large scale culture of the strain and its stability in a dry formulation. Growth rate of Bifidobacterium crudilactis FR62/b/3 was optimal at a pH of 5.0 and a temperature of 37°C. At a temperature growth of 33°C and a pH of 5.0, the stationary phase was reached after 22 h, the viable cell number and the mean dry biomass concentration were respectively of 8.3 × 109 CFU/mL and of 2.1 g/L. Resistance of Bifidobacterium crudilactis FR62/b/3 to freeze-drying and effect of a variety of cryoprotectants to maintain the viability were also evaluated. Sorbitol was the most suitable cryoprotectant for freeze-drying as well as storage whereas sucrose and monosodium glutamate were only efficient during storage.

25-hydroxycholecalciferol reverses heat induced alterations in bone quality in finisher broilers associated with effects on intestinal integrity and inflammation

Background:Alterations in ambient temperature have been associated with multiple detrimental effects on broilers such as intestinal barrier disruption and dysbiosis resulting in systemic inflammation.Inflammation and 25-hydroxycholecalciferol(25-OH-D_(3))have shown to play a negative and positive role,respectively,in the regulation of bone mass.Hence the potential of 25-OH-D_(3)in alleviating heat induced bone alterations and its mechanisms was studied.Results:Heat stress(HS)directly induced a decrease in tibia material properties and bone mass,as demonstrated by lower mineral content,and HS caused a notable increase in intestinal permeability.Treatment with dietary 25-OH-D_(3)reversed the HS-induced bone loss and barrier leak.Broilers suffering from HS exhibited dysbiosis and increased expression of inflammatory cytokines in the ileum and bone marrow,as well as increased osteoclast number and activity.The changes were prevented by dietary 25-OH-D_(3)administration.Specifically,dietary 25-OH-D_(3)addition decreased abundance of B-and T-cells in blood,and the expression of inflammatory cytokines,especially TNF-α,in both the ileum and bone marrow,but did not alter the diversity and population or composition of major bacterial phyla.With regard to bone remodeling,dietary 25-OH-D_(3)supplementation was linked to a decrease in serum C-terminal cross-linked telopeptide of type I collagen reflecting bone resorption and a concomitant decrement in osteoclast-specific marker genes expression(e.g.cathepsin K),whereas it did not apparently change serum bone formation markers during HS.Conclusions:These data underscore the damage of HS to intestinal integrity and bone health,as well as that dietary 25-OH-D_(3)supplementation was identified as a potential therapy for preventing these adverse effects.