Effects of milk fermented by culturing with various lactic acid bacteria and a yeast on serum cholesterol level in rats

AB-Kefir Reduced Body Weight and Ameliorated Inflammation in Adipose Tissue of Obese Mice Fed a High-Fat Diet, but Not a High-Sucrose Diet

Consumption of different types of high-calorie foods leads to the development of various metabolic disorders. However, the effects of multi-strain probiotics on different types of diet-induced obesity and intestinal dysbiosis remain unclear. In this study, mice were fed a control diet, high-fat diet (HFD; 60% kcal fat and 20% kcal carbohydrate), or western diet (WD; 40% kcal fat and 43% kcal carbohydrate) and administered with multi-strain AB-Kefir containing six strains of lactic acid bacteria and a Bifidobacterium strain, at 10⁹ CFU per mouse for 10 weeks. Results demonstrated that AB-Kefir reduced body weight gain, glucose intolerance, and hepatic steatosis with a minor influence on gut microbiota composition in HFD-fed mice, but not in WD-fed mice. In addition, AB-Kefir significantly reduced the weight and size of adipose tissues by regulating the expression of CD36, Igf1, and Pgc1 in HFD-fed mice. Although AB-Kefir did not reduce the volume of white adipose tissue, it markedly regulated CD36, Dgat1 and Mogat1 mRNA expression. Moreover, the abundance of Eubacterium_coprostanoligenes_group and Ruminiclostridium significantly correlated with changes in body weight, liver weight, and fasting glucose in test mice. Overall, this study provides important evidence to understand the interactions between probiotics, gut microbiota, and diet in obesity treatment.

Hypocholesterolemic Effect of Potential Probiotic Lactobacillus fermentum Strains Isolated from Traditional Fermented Foods in Wistar Rats

The current research project was undertaken to explore the therapeutic potential of two potent probiotic Lactobacillus fermentum strains, i.e., PD2 and PH5 in a hyperlipemic healthy adult Wistar rat model, with a particular focus as biotherapeutics for the management of high cholesterol in Indian population. Rats fed on cholesterol-enriched diet supplemented with potential probiotics strain Lactobacillus fermentum PH5 significantly affected serum lipid profile by reducing serum cholesterol (67.21%), triglycerides level (66.21%), and LDL cholesterol level (63.25%) in comparison to rats that received cholesterol-enriched diet (Model) only. Both the strains decreased the cholesterol levels in liver compared with Model group, but PH5 was found to be more effective (30.65% reduction) in liver total cholesterol (TC) lowering action. In addition, the fecal coliforms were significantly reduced besides increased LAB in feces of rats receiving probiotic curd having Lactobacillus fermentum PH5. Our results demonstrated that supplementation with either of the two strains was efficient in reducing serum cholesterol, LDL-cholesterol and TG concentrations in rats compared to those fed the same high-cholesterol diet but without LAB supplementation.

In vitro and in vivo cholesterol lowering ability of Lactobacillus pentosus KF923750

Lactobacillus pentosus KF923750 was characterised for probiotic related properties and then characterised for cholesterol uptake in vitro as well as in vivo using rabbits fed a high-cholesterol diet. The survival percentage of L. pentosus KF923750 was 100% at pH 3, 52.18% at pH 2 and 36.21% at pH 2 plus pepsin. Similarly, this strain appeared resistant to bile (0.1% [98.42%], 0.3% [88.52%], 0.5% [75.60%] and 1% [71.15%]), after 4 h exposure. Moreover, L. pentosus KF923750 controlled growth of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923 through the production of a bacteriocin-like inhibitory substance and anti-adhesive capabilities. L. pentosus KF923750 was non-cytotoxic to eukaryotic cells but sensitive to some antibiotics. Compared with rabbits fed a high-cholesterol diet but without L. pentosus KF923750 supplementation, the plasma total cholesterol, low-density lipoprotein cholesterol and triglycerides levels were significantly decreased in L. pentosus KF923750-fed rabbits by 11.54, 16.00 and 18.00%, respectively, with no significant change in high-density lipoprotein cholesterol levels. The histological sections of livers revealed lesions in all the rabbits that were fed a high-cholesterol diet, but these were less pronounced in rabbits ingesting L. pentosus KF923750. This study highlights the potential of lactobacilli, such as L. pentosus KF923750, in the treatment or prevention of hypercholesterolemia.

Effects of single or combined dietary supplementation of β-glucan and kefir on growth performance, blood characteristics and meat quality in broilers

1. This study was conducted to evaluate the effects of dietary β-glucan and kefir (a fermented milk product) on growth performance, blood profiles, relative organ weight and meat quality in broilers. 2. A total of 375 day-of-hatch mixed sex ROSS 308 broilers (BW of 46 ± 0.1 g) were used in a 5-week experiment and randomly allotted to one of the following dietary treatments: (1) NC, basal diet; (2) PC, basal diet + 40 mg/kg of avilamycin; (3) B, NC + 0.1% β-glucan; (4) K, NC + 0.1% kefir; (5) BK, NC + 0.1% β-glucan + 0.1% kefir. 3. During weeks 0-3, broilers in B, K and BK treatments had higher body weight gain (BWG) than those in NC treatment. During weeks 4-5, BK treatment had a higher BWG than NC treatment. Overall, broilers given PC, K and BK diets had higher BWG than those given NC diet. The feed efficiency ratio (FCR) was improved by PC treatment. 4. Relative liver weight was increased by B treatment, whereas the relative weight of breast meat and gizzard was higher in BK group than that in NC group. Broilers given PC, B and BK diets had greater breast meat redness value and reduced drip loss at d 5 and d 7. The cooking loss was also reduced by B and BK treatments compared with NC treatment. 5. In conclusion, the results suggested that inclusion of 0.1% β-glucan and 0.1% kefir, either individually or combined, would improve growth performance and benefit meat quality in broiler chickens.

Evaluation of low-intensity laser radiation on stimulating the cholesterol degrading activity: Part I. Microorganisms isolated from cholesterol-rich materials

A survey was performed to isolate bacteria and fungi from cholesterol-rich sources including chicken liver, turkey giblets, salmon, lamb, egg yolk, beef brain and shrimps. A total of 34 bacterial and 22 fungal isolates were recovered from the tested sources. The highest count of isolates was recovered from the soil (12 isolates/g), followed by turkey giblets and egg yolk (8 isolates/g, for each). Out of 34 bacterial isolates, five induced the highest level in cholesterol degradation. The most potent bacterial isolate was recovered from turkey giblets and was identified as Streptomyces fradiae. In a trial to increase the cholesterol decomposing potentiality of S. fradiae, low intensity Nd-YAG laser irradiation was evaluated. The exposure of the chlorophyllin - photosensitized bacterium to 210 mW Nd-YAG laser for 8 min induced significant increase in cholesterol degrading activity reaching 73.8% as compared with 54.2% in the case of non-irradiated, non-photosensitized culture. Under the same conditions but using the reaction mixture containing cholesterol as a substrate and extracellular crude enzyme, the percent decomposition reached 53.7% for the irradiated culture as compared to 28.3% in the case of the control. Our data indicate the importance of the photosensitizer in enhancement of laser radiation to stimulate cholesterol decomposition of S. fradiae.

Probiotic lactic acid bacteria in the gastro-intestinal tract: health benefits, safety and mode of action

Lactic acid bacteria (LAB) have received considerable attention as probiotics over the past few years. This concept has grown from traditional dairy products to a profitable market of probiotic health supplements and functional foods. Extensive research is done on novel potential probiotic strains, with specific emphasis on their health benefits and mode of action. Criteria for the selection of probiotic strains have only recently been formulated by the Food and Agriculture Organization of the United Nations and the World Health Organization (FAO/WHO). Several in vitro techniques have been developed to evaluate the probiotic properties of strains. In many cases, this is followed by in vivo tests. Safety studies are also obligatory, as a few cases of bacteremia caused by LAB have been reported. This review focuses on the health benefits and safety of LAB probiotics, the criteria used to select a probiotic, mode of action and the impact these organisms have on natural microbiota in the gastro-intestinal tract.

Kefir: a symbiotic yeasts-bacteria community with alleged healthy capabilities

Kefir is a fermented milk beverage. The milk fermentation is achieved by the of kefir grains, a cluster of microorganisms held together by a polysaccharide matrix named kefiran. Kefir grains are an example of symbiosis between yeast and bacteria. They have been used over years to produce kefir, a fermented beverage that is consumed all over the world, although its origin is Caucasian. A vast variety of different species of organisms forming the kefir grains, comprising yeast and bacteria, have been isolated and identified. Kefir is a probiotic food. Probiotics have shown to be beneficial to health, being presently of great interest to the food industry. Kefir has been accredited with antibacterial, antifungal and antitumoural activities among other beneficial attributes. This review includes a critical revision of the microbiological composition of kefir along with its beneficial properties to human health.

Characterisation and selection of probiotic lactobacilli for a preliminary minipig feeding trial and their effect on serum cholesterol levels, faeces pH and faeces moisture content

Three out of 297 Lactobacillus strains isolated from pig faeces were selected for a feeding trial on account of their high bile-salt hydrolase (BSH) activity, bile-salt resistance, low pH tolerance and the production of antimicrobial substances. Two strains were identified as Lactobacillus johnsonii and one as Lactobacillus reuteri by DNA-DNA hybridisation. L. johnsoniii BFE 1061 produced a bacteriocin active against a range of lactic acid bacteria (LAB) and nonrelated bacteria including Clostridium perfringens. Six minipigs were maintained on a high-fat, high-cholesterol ('Western Style') diet for 17 weeks after which the diet was supplemented with the 'probiotic mixture' containing the above mentioned three Lactobacillus strains at 2 x 10(12) CFU per pig per day for five weeks. The mixture was given as a resuspended lyophilisate. During a two week follow-up period the minipigs received only the 'Western-style' diet without probiotic supplementation. A lowering effect on serum cholesterol levels was indicated after three weeks probiotic feeding, concomitant with an increase in the moisture content of the faeces and Lactobacillus cell numbers. Triglycerides, pH and number of lactic acid bacteria in faeces were not significantly influenced by probiotic supplementation.