Cholesterol assimilation, acid and bile survival of probiotic bacteria isolated from food and reference strains

Abstract

The evidence shows that probiotics can reduce cardiovascular diseases associated to high cholesterol levels, but it occurs just when they survive gastrointestinal conditions. The aim of this study was to evaluate the ability of reference strains (RS) and food isolates strains (FIS) to survive acid and bile and to determine in-vitro cholesterol assimilation. FIS were more tolerant to acid than RS, showing significantly different growth response. FIS were more resistant to the presence of bile, in order descendent to oxgall, taurocholic acid, and cholic acid. The survival percentages ranged from 0% to 100%, presenting strain dependence. The most tolerant strains were tested for cholesterol test, showing RS lower percentages than FIS. In FIS, the percentage was negatively affected when the concentration of bile salt was increased. Therefore, to study the viability of different strains in gastrointestinal conditions is crucial because of the strain-dependence nature.Asimilación de colesterol y supervivencia al ácido y bilis de bacterias probióticas aisladas de alimentos y cepas de referencia RESUMEN La evidencia científica muestra que los probióticos pueden reducer enfermedades cardiovasculares asociadas a altos niveles de colesterol pero sólo cuando sobreviven a condiciones gastrointestinales. El objetivo del estudio fue evaluar la supervivencia a ácido y bilis de cepas aisladas de alimentos (FIS) y de referencia (RS) y determinar in vitro, su asimilación de colesterol. FIS mostraron mayor tolerancia al ácido que RS, mostrando diferencias significativas en el crecimiento. FIS mostró mayor resistencia a la bilis; en orden descendente: oxgall, ácido taurocólico y ácido cólico. El porcentaje de supervivencia fue 0-100%, siendo cepa dependiente. Las cepas más tolerantes fueron evaluadas para su asimilación de colesterol, mostrando RS menores porcentajes que FIS. En éstas, el porcentaje fue afectado negativamente al incrementar la concentración de la sal biliar. Por lo tanto, es importante evaluar la viabilidad de las cepas en condiciones intestianles por su caracter cepadependiente. ARTICLE HISTORY

Lactobacillus fermentum strains from human breast milk with probiotic properties and cholesterol-lowering effects

“…The properties of anti-cholesterol of some probiotic lactic acid bacteria have been reported in the literature. Castorena-Alba et al (2018) reported the anti-cholesterol activity of L. fermentum food isolates strains as 57.65% at 4% concentration of oxgall and cholesterol (100 lg/mL). Tulumoglu et al (2014) reported cholesterol assimilation ability of seven L. fermentum strains isolated from Tulum cheese ranging from 12.1 to 45.3%.…”

“…Consumption of cholesterol rich food can lead to increased blood cholesterol levels and develop hypercholesterolaemia (Castorena-Alba et al, 2018). It has also been reported that hypercholesterolemia is a health problem associated with the dysbiosis of the intestinal microbiota (Lye et al, 2017).…”

“…The present study was aimed to carry out identification and characterization of L. fermentum originated from human breast milk and evaluated for some desirable traits in probiotic microorganisms including antibiotic sensitivity, resistance to gastrointestinal system conditions; transit tolerance, hemolytic and auto-aggregation activities. The cholesterol-lowering effects of L. fermentum isolated from different sources (koumiss, traditional dairy products, commercial yoghurt, Tulum cheese, food) have been investigated in the literature (Bao et al, 2010;Castorena-Alba et al, 2018;Pan et al, 2011;Raghavan et al, 2011;Tulumoglu et al, 2014). However, a very limited number of studies have been reported on cholesterol lowering potential of L. fermentum strains originated from human breast milk.…”

Lactobacillus paracasei DTA81, a cholesterol‐lowering strain having immunomodulatory activity, reveals gut microbiota regulation capability in BALB/c mice receiving high‐fat diet

“…Taking into account the published data in the literature, cholesterol assimilation by probiotic strains can range from 0Á86% to more than 40%; however, we usually do not see the same reduction when we use probiotics in the in-vivo conditions, which can be due to the effect of gastrointestinal conditions of the strains, microbial competition, colonization on the epithelial cells, etc. (Belviso et al 2009;Tokatlı et al 2015;Castorena-Alba et al 2018). The outcome of our study indicates that consumption of L. paracasei DTA81 can lead in mice to a statistically significant reduction of total cholesterol and LDL and HDL, which appears very interesting and useful in people who suffer from CVD and CHD.…”

“…In their study, Shimizu et al (2015) reported that consumption of probiotics by elderly and hypercholesterolaemic patients could be more effective than in youngsters and individuals with normal lipid levels. Besides, probiotics can reduce cholesterol levels by assimilating and entrapping this molecule into bacterial membranes (Castorena-Alba et al 2018;Bhat and Bajaj 2020). There are numerous species of Lactobacillus and Bifidobacterium that have shown cholesterol assimilation in in-vitro experiments and it has been reported that this ability is strictly strain-…”