Evaluation of the postbiotic potential of inactivated Lacticaseibacillus rhamnosus GG via spray drying on the in vitro anti-inflammatory effects and its impact in obese Wistar rats

Abstract

Obesity is a metabolic disease featured by low-grade systemic inflammation, influenced by the interaction of several factors as lifestyle, inadequate eating habits, genetic factors, and obesogenic environment. Pro-inflammatory biomarkers are released by means of expansion and hypoxia of adipose tissue, as well as by the intestinal translocation process of bacterial lipopolysaccharide (LPS). The postbiotics (inactivated microbial cells) might promote biological activities, such as reduction of bacterial translocation, preservation of the intestinal barrier, modulation of the intestinal microbiota, and immunomodulation; which effects might vary according to the probiotic strain, intensity and method of inactivation applied. In this research project, the aim is to obtain skimmed postbiotic milk powder for the first time, through a process of spray drying and inactivation of cells of a probiotic strain (Lacticaseibacillus rhamnosus GG), and subsequently, to evaluate its in vitro anti-inflammatory potential and the impact of their ingestion in obese Wistar rats. The best parameters associated to atomization process for the inactivation of L. rhamnosus GG in skimmed milk will be determined, aiming to evaluate the effects of these process parameters on the adhesion of the postbiotics obtained in Caco-2 cells, in vitro anti-inflammatory activity, in addition to the impact of this milk powder containing postbiotic on the health of obese rats over 4 weeks of supplementation. It is expected that the results obtained by this project provide robust scientific evidence on the possible benefits of this probiotic strain inactivated via spray drying on the obesity. By elucidating of the mechanisms of beneficial effects related to ingestion of postbiotics, it will be possible to develop a skimmed postbiotic milk powder; an innovative patentable product with several advantages in relation to probiotics. Thus, it will be possible to collaborate to the expansion of the concept of use of bacteria beneficial to human health. (AU)