Control Of Intestinal Infections Research Articles

Chitosan and HPMCAS double-coating as protective systems for alginate microparticles loaded with Ctx(Ile21)-Ha antimicrobial peptide to prevent intestinal infections

The incorrect use of conventional drugs for both prevention and control of intestinal infections has contributed to a significant spread of bacterial resistance. In this way, studies that promote their replacement are a priority. In the last decade, the use of antimicrobial peptides (AMP), especially Ctx(Ile21)-Ha AMP, has gained strength, demonstrating efficient antimicrobial activity (AA) against pathogens, including multidrug-resistant bacteria. However, gastrointestinal degradation does not allow its direct oral application. In this research, double-coating systems using alginate microparticles loaded with Ctx(Ile21)-Ha peptide were designed, and in vitro release assays simulating the gastrointestinal tract were evaluated. Also, the AA against Salmonella spp. and Escherichia coli was examined. The results showed the physicochemical stability of Ctx(Ile21)-Ha peptide in the system and its potent antimicrobial activity. In addition, the combination of HPMCAS and chitosan as a gastric protection system can be promising for peptide carriers or other low pH-sensitive molecules, adequately released in the intestine. In conclusion, the coated systems employed in this study can improve the formulation of new foods or biopharmaceutical products for specific application against intestinal pathogens in animal production or, possibly, in the near future, in human health.

The gut flora is required for the control of intestinal infection by poly(I:C) administration in neonates

We found that immunostimulation of the intestinal immune system of neonatal mice by poly(I:C) injection decreased intestinal infection by the parasite Cryptosporidium parvum. We showed that the presence of dendritic cells and the cooperation of mutually dependent cytokines, such as IL-12p40, and type I and type II IFNs, were involved in the mechanism of protection induced by poly(I:C). This protection is dependent not only on TLR3-TRIF signaling, but also on the activation of the TLR5-MyD88 pathway by gut microbiota. These results raise the possibility that flagellated intestinal commensal bacteria may, in the presence of natural or synthetic agonists of TLR3, provide synergy between the TRIF and MyD88 signaling pathways, thereby favoring the development of mucosal defenses. In this addendum, we summarize these recent findings and discuss their implications for neonatal infections and immunomodulatory strategies.

Microbes to Fight Microbes

For centuries, fermentation of milk products using specific bacteria or cultures has been a way to preserve dairy foods. In 1908, Metchnikoff suggested that ingested lactobacilli could displace toxin‐producing microorganisms in the gastrointestinal (GI) tract and thus promote health and prolong life (1). In the latter half of this century, evidence mounted in support of the concept that the preservation of gut microflora in animals is necessary to prevent infections. It was recognized that germ‐free animals are more susceptible to infection than animals colonized with microflora (2) and that giving fecal suspensions orally to animals could prevent infection (3). Fecal enemas were successfully administered to humans to control C. difficile infection (4); conversely, it was recognized that antibiotics can alter intestinal flora and induce diarrhea. All this information led to the concept that a healthy or balanced microflora is necessary for maintaining the health of the host; one way to maintain balanced microflora is to ingest exogenous bacteria in order to incorporate them into the gut milieu. Many published observations have claimed a variety of health benefits from several microbial agents. Among the benefits attributed to the consumption of these organisms are improvement of lactose absorption and tolerance, control of intestinal infections, anticarcinogenic properties, anticholesterolemic effects, and improvement of GI motility (5,6). These attributions became part of the nutritional folklore that has conferred upon yogurt and other cultured milk products the status of “health foods.‘’

Acidophilus milk products: Manufacture and therapeutics

Abstract Consumption of acidophilus milk products as a dietary adjunct is considered to impart many health benefits. These include (i) control of intestinal infections, (ii) stabilization of intestinal micro‐flora, (iii) control of serum cholesterol level, (iv) prevention of colon cancer, and (v) enhanced availability of nutrients. However, L. acidophilus grows slowly in milk, which results in overgrowth of other microorganisms present. Hence, acidophilus milk products are characterized by an unpleasant flavor and are not acceptable as a normal component of diet. Attempts have, therefore, been made to manufacture acceptable acidophilus milk products possessing wider consumer appeal. The manufacturing and therapeutical aspects of acidophilus milk products are discussed in this review.

Lactic Acid Fermentation as Biotechnological Method for Obtaining Milk-Based Special-Diet and Therapeutic Foods

Lactic acid fermentation due to metabolism of lactobacilli is a biotechnological method for obtaining milk-based special diet and therapeutic foods. There are several potential health or nutritional benefits possible from some species of lactic acid bacteria: improved nutritional value of food, control of intestinal infections, improved digestion of lactose, control of some types of cancer and control of serum cholesterol levels. In selecting a culture to produce a specific benefit it is necessary to consider not only the wide variation among species of the lactic acid bacteria but also that among strains within given species. In ELBY Engineering-G available now are strains of lactic acid bacteria and symbiotic starters ensuring that associated growth proceeds in the fermented milk products. On this basis, special-diet and therapeutic foods with the characteristics desired were obtained. The lactic acid cultures of L. bulgaricus display antagonistic properties against harmful microflora within food products as well as within the human body.

Health and nutritional benefits from lactic acid bacteria

There are several potential health or nutritional benefits possible from some species of lactic acid bacteria. Among these are: improved nutritional value of food, control of intestinal infections, improved digestion of lactose, control of some types of cancer, and control of serum cholesterol levels. Some potential benefits may result from growth and action of the bacteria during the manufacture of cultured foods. Some may result from growth and action of certain species of the lactic acid bacteria in the intestinal tract following ingestion of foods containing them. In selecting a culture to produce a specific benefit it is necessary to consider not only the wide variation among species of the lactic acid bacteria but also that among strains within a given species. With the possible exception of improving lactose utilization by persons who are lactose maldigestors, no specific health or nutritional claims can yet be made for the lactic acid bacteria.

Health and nutritional benefits from lactic acid bacteria

There are several potential health or nutritional benefits possible from some species of lactic acid bacteria. Among these are: improved nutritional value of food, control of intestinal infections, improved digestion of lactose, control of some types of cancer, and control of serum cholesterol levels. Some potential benefits may result from growth and action of the bacteria during the manufacture of cultured foods. Some may result from growth and action of certain species of the lactic acid bacteria in the intestinal tract following ingestion of foods containing them. In selecting a culture to produce a specific benefit it is necessary to consider not only the wide variation among species of the lactic acid bacteria but also that among strains within a given species. With the possible exception of improving lactose utilization by persons who are lactose maldigestors, no specific health or nutritional claims can yet be made for the lactic acid bacteria.