Functional Probiotic Assessment andIn VivoCholesterol-Lowering Efficacy ofWeissellasp. Associated with Arid Lands Living-Hosts

Abstract

The research and the selection of novel probiotic strains from novel niches are receiving increased attention on their proclaimed health benefits to both humans and animals. This study aimed to evaluate the functional properties ofWeissellastrains from arid land living-hosts and to select strains with cholesterol-lowering propertyin vitroandin vivo, for use as probiotics. They were assessed for acid and bile tolerance, antibiotic susceptibility, membrane properties, antibacterial activity, antiadhesive effect against pathogens to host cell lines, and cholesterol assimilationin vitro. Our results showed that the majority of strains revealed resistance to gastrointestinal conditions. All the strains were nonhemolytic and sensitive to most of the tested antibiotics. They also exhibited high rates of autoaggregation and some of them showed high coaggregation with selected pathogens and high adhesion ability to two different cell lines (Caco-2 and MIM/PPk). Particularly,W. halotoleransF99, from camel feces, presented a broad antibacterial spectrum against pathogens, reducedEnterococcus faecalisandEscherichia coliadhesion to Caco-2 cells, and was found to reduce,in vitro, the cholesterol level by 49 %. Moreover,W. halotoleransF99 was evaluated for the carbohydrate utilization as well as the serum lipid metabolism effect in Wistar rats fed a high-cholesterol diet.W. halotoleransF99 showed an interesting growth on different plant-derivative oligosaccharides as sole carbon sources. Compared with rats fed a high-fat (HF) diet withoutWeissellaadministration, total serum cholesterol, low-density lipoprotein cholesterol, and triglycerides levels were significantly (p<0.001) reduced inW. halotoleransF99-treated HF rats, with no significant change in high-density lipoprotein cholesterol HDL-C levels. On the basis of these results, this is the first study to report thatW. halotoleransF99, from camel feces, can be developed as cholesterol-reducing probiotic strain. Further studies may reveal their potential and possible biotechnological and probiotic applications.