Characterization of Lactobacillus plantarum PH04, a potential probiotic bacterium with cholesterol-lowering effects

Effects of Lactobacillus gasseri BNR17 on body weight and adipose tissue mass in diet-induced overweight rats

We investigated the weight-gain suppressive effect of Lactobacillus gasseri BNR17 isolated from human breast milk. Rats were fed a high-carbohydrate diet and administered BNR17 (BNR17 group) twice daily for twelve weeks. Changes were observed in body weight and white adipose tissue mass. The percent increase in body weight (P=0.0331) and fat pad mass (P<0.01) was significantly lower in the BNR17 group, and the FER was moderately lower (P=0.0769). These data suggest that BNR17 can prevent diet-induced overweight and may become an alternative method for treating weight problems and obesity.

Hypocholesterolaemic effect of dietary inclusion of two putative probiotic bile salt hydrolase-producing Lactobacillus plantarum strains in Sprague-Dawley rats

The purpose of the present study was to evaluate the anti-hypercholesterolaemic effects of two putative probiotic bile salt hydrolase (Bsh)-producing Lactobacillus plantarum strains, i.e. Lp91 and Lp21, in rats. L. plantarum Lp91 exhibited excellent tolerance to low pH and high bile salt concentrations as well as showed potential Bsh activity, cholesterol assimilation and cholesterol co-precipitation ability along with L. plantarum Lp21 and NCDO82 strains. Furthermore, the potential effect of L. plantarum Lp91 on plasma cholesterol level was evaluated in Sprague-Dawley rats. Five treatment groups of rats (n 6) were fed experimental diets: normal diet, hypercholesterolaemic diet (HD), HD plus L. plantarum Lp91 (HD91) at ≥ 1·0 × 108 colony-forming units (cfu)/g, HD plus microencapsulated L. plantarum Lp91 (HDCap91) at ≥ 1·0 × 108 cfu/g and HD plus L. plantarum Lp21 (HD21) at ≥ 1·0 × 108 cfu/g for 3 weeks. Feed intake and feed efficiency differed significantly among the five groups. After 21 d of dietary treatment, comparative analysis revealed 23·26, 15·71 and 15·01 % reduction in total cholesterol, 21·09, 18·77 and 18·17 % reduction in TAG, 38·13, 23·22 and 21·42 % reduction in LDL-cholesterol, and the corresponding HDL-cholesterol values increased at the rate of 18·94, 10·30 and 7·78 % in treated groups HD91, HDCap91 and HD21, respectively. Faecal excretion of cholic acid and faecal lactobacilli counts were significantly higher in the probiotic treatment groups than in the control groups. In conclusion, these results suggest that the indigenous L. plantarum Lp91 strain has the potential to be explored as a probiotic in the management of hypercholesterolaemia.

Characterization of lactic acid bacteria isolated from Italian Bella di Cerignola table olives: selection of potential multifunctional starter cultures

Lactic acid bacteria (19 isolates) from Bella di Cerignola Italian table olives were investigated for their technological and probiotic properties for the selection of multifunctional starter cultures for table olives. The bacteria were first identified by phenotyping and genotyping, then characterized for the production of biogenic amines, growth at different pH, NaCl concentrations, and temperatures. The potentiality of the bacteria to have some probiotic properties (antimicrobial activity against foodborne pathogens, survival in low pH and in the presence of bile salts, ability to adhere to the mammalian cells model IPEC-J2) was also investigated. Eighteen of the studied isolates were identified as Lactobacillus plantarum and one as Enterococcus faecalis. All bacteria were able to grow at a range of pH between 4.0 and 10.0 as well as in media supplemented with 2.5 to 7.5% of NaCl and 0.3% bile salts and survived in MRS broth acidified at pH 2.5; moreover, they inhibited significantly Escherichia coli O157:H7. The adhesion to IPEC-J2 cells was in general low to moderate (5.3 to 8.3%); however, 2 isolates of L. plantarum (c16 and c19) showed interesting higher adhesion values (up to 16%). Our results suggest that at least 3 isolates could be possible multifunctional starters for Bella di Cerignola olives: L. plantarum 16 and 19 for mainly their probiotic properties and L. plantarum 10 for mainly its technological characteristics. Practical Application: A functional starter is a microorganism exerting benefits on human health (probiotic) and able to guide a fermentation (starter). The main goal of this article was to select a functional starter for table olives.

Cholesterol-lowering effects of probiotics and prebiotics: a review of in vivo and in vitro findings

Probiotics are live microorganisms that promote health benefits upon consumption, while prebiotics are nondigestible food ingredients that selectively stimulate the growth of beneficial microorganisms in the gastrointestinal tract. Probiotics and/or prebiotics could be used as alternative supplements to exert health benefits, including cholesterol-lowering effects on humans. Past in vivo studies showed that the administration of probiotics and/or prebiotics are effective in improving lipid profiles, including the reduction of serum/plasma total cholesterol, LDL-cholesterol and triglycerides or increment of HDL-cholesterol. However, other past studies have also shown that probiotics and prebiotics had insignificant effects on lipid profiles, disputing the hypocholesterolemic claim. Additionally, little information is available on the effective dosage of probiotics and prebiotics needed to exert hypocholesterolemic effects. Probiotics and prebiotics have been suggested to reduce cholesterol via various mechanisms. However, more clinical evidence is needed to strengthen these proposals. Safety issues regarding probiotics and/or prebiotics have also been raised despite their long history of safe use. Although probiotic-mediated infections are rare, several cases of systemic infections caused by probiotics have been reported and the issue of antibiotic resistance has sparked much debate. Prebiotics, classified as food ingredients, are generally considered safe, but overconsumption could cause intestinal discomfort. Conscientious prescription of probiotics and/or prebiotics is crucial, especially when administering to specific high risk groups such as infants, the elderly and the immuno-compromised.

Bile salt deconjugation and cholesterol removal from media by Lactobacillus strains used as probiotics in chickens

BACKGROUND

Bile salt deconjugation by Lactobacillus strains is often closely linked to bile tolerance and survival of the strains in the gut and lowering of cholesterol in the host. The present study investigated the deconjugation of bile salts and removal of cholesterol by 12 Lactobacillus strains in vitro. The 12 strains were previously isolated from the gastrointestinal tract of chickens.

RESULTS

The 12 Lactobacillus strains could deconjugate sodium glycocholate (GCA, 16.87-100%) and sodium taurocholate (TCA, 1.69-57.43%) bile salts to varying degrees, with all strains except L. salivarius I 24 having a higher affinity for GCA. The 12 Lactobacillus strains also showed significant (P < 0.05) differences in their ability to remove cholesterol from the growth medium (26.74-85.41%). Significant (P < 0.05) correlations were observed between cholesterol removal and deconjugation of TCA (r = 0.83) among the L. reuteri strains (C1, C10 and C16) and between cholesterol removal and deconjugation of TCA (r = 0.38) and GCA (r = 0.70) among the L. brevis strains (I 12, I 23, I 25, I 211 and I 218). In contrast, although L. gallinarum I 16 and I 26 and L. panis C 17 showed high deconjugating activity, there was no correlation between cholesterol removal and deconjugation of bile salts in these strains.

CONCLUSION

The results showed that the 12 Lactobacillus strains were able to deconjugate bile salts and remove cholesterol in vitro, but not all strains with high deconjugating activity removed cholesterol effectively.

Orally delivered microencapsulated live probiotic formulation lowers serum lipids in hypercholesterolemic hamsters

Elevated serum cholesterol is a major risk factor for coronary artery disease. Nutritional therapies such as probiotics have been suggested to manage elevated cholesterol. This study investigates the cholesterol and triglyceride lowering potential of a microencapsulated feruloyl esterase-producing Lactobacillus fermentum 11976 (LF11976) probiotic formulation. Male Bio F(1)B hamsters were assigned to two groups to receive either the microcapsule probiotic formulation (containing LF11976 cells at 12.51 log colony-forming units/mL) or placebo formulation (empty) microcapsules, twice daily, by oral gavage for 18 weeks. For the duration of the study, animals were fed a hypercholesterolemic diet. Serum total cholesterol, low-density lipoprotein (LDL) cholesterol, and the atherogenic index were 21.36%, 31.43%, and 32.59% lower in the group gavaged with the microencapsulated probiotic formulation than in the placebo control group after 18 weeks (P < .05). Histology studies showed reduced progression of atherosclerotic lesions in animals treated with microencapsulated LF11976 as compared to control animals. Treatment with microencapsulated LF11976 formulation produces significant reductions in serum total cholesterol, LDL cholesterol, and serum triglyceride levels in diet-induced hypercholesterolemic hamsters. Findings suggest the potential of the oral microencapsulated probiotic cell formulation as a functional nutritional alternative for managing excessive serum cholesterol and triglyceride levels.

Probiotic bile salt hydrolase: current developments and perspectives

Probiotic has modernized the current dietetic sense with novel therapeutic and nutritional benefits to the consumers. The presence of bile salt hydrolase (BSH) in probiotics renders them more tolerant to bile salts, which also helps to reduce the blood cholesterol level of the host. This review focuses on the occurrence of bile salt hydrolase among probiotics and its characterization, importance, applications, and genetics involved with recent updates. Research on bile salt hydrolase is still in its infancy. The current perspective reveals a huge market potential of probiotics with bile salt hydrolase. Intensive research in this field is desired to resolve some of the lacunae.

Thermal, chemical, and photocatalytic inactivation of Lactobacillus plantarum bacteriophages

The effect of several biocides, thermal treatments, and photocatalysis on the viability of four Lactobacillus plantarum phages was investigated. Times to achieve 99% inactivation (T99) of phages at 63, 72, and 90 degrees C were evaluated in four suspension media: deMan Rogosa Sharpe broth, reconstituted skim milk, a commercial EM-glucose medium, and Tris magnesium gelatin buffer. The four phages studied were highly resistant to 63 degrees C (T99 > 45 min); however, counts < 10 PFU/ml were achieved by heating at 90 degrees C for 5 min. Higher thermal resistance at 72 degrees C was observed when reconstituted skim milk and EM-glucose medium were assayed. Peracetic acid (0.15%, vol/vol) was an effective biocide for the complete inactivation of all phages studied within 5 min of exposure. Sodium hypochlorite (800 ppm) inactivated the phages completely within 30 min. Ethanol (100%) did not destroy phage particles even after 45 min. Isopropanol did not have any effect on phage viability. Phage counts < 50 PFU/ml were obtained within 180 min of photocatalytic treatment. The results obtained in this work are important for establishing adequate methods for inactivating phages in industrial plants and laboratory environments.