Peptides, Exopolysaccharides, and Short-Chain Fatty Acids from Fermented Milk and Perspectives on Inflammatory Bowel Diseases

Crohn's disease and ulcerative colitis are characterized by chronic inflammatory processes and an imbalanced immune response along the gastrointestinal (GI) tract. Pharmacological treatments have been widely used, although their long-term application has adverse side effects. On the other hand, milks fermented with specific lactic acid bacteria (LAB) have been shown to be useful as alternative or complementary aids. Many metabolites such as peptides, exopolysaccharides, and short-chain fatty acids are produced during milk fermentation. These components have been shown to change the pH of the gastrointestinal lumen, aid intestine mucosal recovery, modulate the microbiota, and reduce the inflammatory response (innate and adaptive immune system), both in vitro and in vivo. Therefore, the objective of the present review is to describe how these bioactive compounds from fermented milk by specific LAB can decrease the deleterious symptoms of inflammatory bowel disease.

Nutraceuticals for the Treatment of IBD: Current Progress and Future Directions

Inflammatory bowel disease (IBD) is a chronic relapsing-remitting inflammatory disease of the gastrointestinal tract. Patients are usually diagnosed in adolescence and early adulthood and need lifelong treatment. In recent years, it has been found that diet plays an important role in the pathogenesis of IBD. Diet can change intestinal barrier function, affect the structure and function of intestinal flora, and promote immune disorder, thus promoting inflammation. Many patients believe that diet plays a role in the onset and treatment of the disease and changes their diet spontaneously. This review provides some insights into how nutraceuticals regulate intestinal immune homeostasis and improve intestinal barrier function. We reviewed the research results of dietary fiber, polyphenols, bioactive peptides, and other nutraceuticals in the prevention and treatment of IBD and sought better alternative or supplementary treatment methods for IBD patients.

Conventional and in silico approaches to select promising food-derived bioactive peptides: A review

•

Seaweed and edible insects are considered new sources of bioactive peptides.

•

Conventional approaches are necessary to validate the bioactivity of peptides.

•

Bioinformatics tools accelerate the obtaining of bioactive peptides.

•

The integrated approach is a promising strategy to obtain bioactive peptides.

The interest for food-derived bioactive peptides, either from common or unconventional sources, has increased due to their potential therapeutic effect against a wide range of diseases. The study of such bioactive peptides using conventional methods is a long journey, expensive and time-consuming. Hence, bioinformatic approaches, which can not only help to predict the formation of bioactive peptides from any known protein source, but also to analyze the protein structure/function relationship, have gained a new meaning in this scientific field. Therefore, this review aims to provides an overview of conventional characterization methods and the most recent advances in the field of in silico approaches for predicting and screening promising food-derived bioactive peptides.

Genetic potential of Sindhi cattle for A2 milk production

ContextCow milk is consumed in many countries. However, its consumption can be associated with gastrointestinal disorders in humans. The genetic profile of β-casein is one of the factors responsible for these disorders and the A1 variant is a causal agent. The β-casein A1 leads to the formation of bioactive peptides, which trigger intestinal reactions. The same is not observed for the A2 allele. A2 milk is obtained from cows with the A2A2 genotype. The identification of breeds and selection of animals for A2 milk production is important for public health and animal production. The Sindhi cattle (Bos taurus indicus) possesses characteristics such as adaptation to hot climate, resistance to parasites and utilisation of low-quality forage that are important for rearing in the tropics. AimsThe objective of the present study was to genotype the single-nucleotide polymorphism (SNP) that forms A1 and A2 alleles of the β-casein in Sindhi cattle. MethodsIn total, 348 Sindhi animals were used. DNA was extracted from hair follicles and submitted to PCR-sequencing for genotyping. Key resultsAllele frequency for A2 was 0.94 and for A1 it was 0.06. Genotype frequencies were 0.90 (A2A2), 0.09 (A1A2) and 0.01 (A1A1). The frequency of the A2A2 genotype in Sindhi cattle was similar to or higher than those found in zebu breeds and higher than those reported for specialised taurine breeds. ConclusionsThis high frequency of the A2A2 genotype indicates a genetic potential of the breed for A2 milk production and easy, assisted selection (if that is the intention). ImplicationsThis information gives importance to the breed and permits to add value to dairy product derived from it. It may increase producer’s income through producing and marketing A2 milk.

Effect of caseinate glycation with oligochitosan and transglutaminase on the intestinal barrier function of the tryptic caseinate digest in IEC-6 cells

The oligochitosan-glycated caseinate digest has higher activity than the caseinate digest to strengthen the intestinal barrier function of IEC-6 cells.

Characterization of Mucus-Related Properties of Streptococcus thermophilus: From Adhesion to Induction

Mucus is a major component of the intestinal barrier involved both in the protection of the host and the fitness of commensals of the gut. Streptococcus thermophilus is consumed world-wide in fermented dairy products and is also recognized as a probiotic, as its consumption is associated with improved lactose digestion. We determined the overall effect of S. thermophilus on the mucus by evaluating its ability to adhere, degrade, modify, or induce the production of mucus and/or mucins. Adhesion was analyzed in vitro using two types of mucins (from pig or human biopsies) and mucus-producing intestinal HT29-MTX cells. The induction of mucus was characterized in two different rodent models, in which S. thermophilus is the unique bacterial species in the digestive tract or transited as a sub-dominant bacterium through a complex microbiota. S. thermophilus LMD-9 and LMG18311 strains did not grow in sugars used to form mucins as the sole carbon source and displayed weak binding to mucus/mucins relative to the highly adhesive TIL448 Lactococcus lactis. The presence of S. thermophilus as the unique bacteria in the digestive tract of gnotobiotic rats led to accumulation of lactate and increased the number of Alcian-Blue positive goblet cells and the amount of the mucus-inducer KLF4 transcription factor. Lactate significantly increased KLF4 protein levels in HT29-MTX cells. Introduction of S. thermophilusvia transit as a sub-dominant bacterium (10³ CFU/g feces) in a complex endogenous microbiota resulted in a slight increase in lactate levels in the digestive tract, no induction of overall mucus production, and moderate induction of sulfated mucin production. We thus show that although S. thermophilus is a poor mucus-adhesive bacterium, it can promote mucus pathway at least in part by producing lactate in the digestive tract.