Assessment of probiotic and sensory properties of dahi and yoghurt prepared using bulk freeze-dried cultures in buffalo milk

Effect of Lactobacillus fermentum MCC2760-Based Probiotic Curd on Hypercholesterolemic C57BL6 Mice

Lactobacillus fermentum MCC2760 is a probiotic strain proven earlier for cholesterol-reducing and anti-inflammatory properties in vitro and in vivo. This study investigates L. fermentum MCC2760-based probiotic curd in high-cholesterol diet (HCD)-fed C57BL6 mice. The mice were grouped into normal diet control, high-cholesterol diet control, normal diet with probiotic supplementation, and high-cholesterol diet with probiotic supplementation. Control groups and treatment groups were supplemented with market curd and probiotic curd, respectively, via oral gavage for eight weeks. The probiotic count was maintained at 10.95 log CFU/mL in the developed probiotic curd. The HCD group showed an increase in feed intake and body weight. Reduction in the levels of serum cholesterol, triglycerides, low-density lipoprotein cholesterol, glucose, aspartate aminotransferase, and alanine transaminase was observed in probiotic-supplemented groups. The probiotic-supplemented group resulted in an increase in Lactobacillus spp. count along with reduced pathogen count in the feces. Probiotic supplementation also showed a reduction in the bacterial translocation count in mesenteric adipose tissue. Expression of inflammatory markers by qPCR showed the decline in the fold change of TNF-α, IL-6, and IL-12 and elevation in the fold change of IL-10 in the adipose tissue of the probiotic-treated group. Probiotic supplementation also improved the expression of GLP-1, ZO-1, and CB2 in the intestine. They were thus possibly playing a role in the enhancement of barrier function. Histopathological sections showed improvement in the cellular infiltration and pathological indications due to the high-cholesterol diet intake. Our study also confirmed that probiotics could increase serum antioxidant enzymes in treated groups, showing their beneficial antioxidant activity. It suggests the anti-inflammatory, antioxidant effect, and gut barrier function of the given probiotic formulation, which ameliorate hypercholesterolemia.

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.

Trends in dairy and non-dairy probiotic products - a review

Health awareness has grown to a greater extent among consumers and they are looking for healthy probiotic counterparts. Keeping in this view, the present review focuses recent developments in dairy and non-dairy probiotic products. All over the world, dairy probiotics are being commercialized in many different forms. However, the allergy and lactose intolerance are the major set-backs to dairy probiotics. Whereas, flavor and refreshing nature are the major advantages of non-dairy drinks, especially fruit juices. Phenotypic and genotypic similarities between dairy and non-dairy probiotics along with the matrix dependency of cell viability and cell functionality are reviewed. The heterogeneous food matrices of non-dairy food carriers are the major constraints for the survival of the probiotics, while the probiotic strains from non-dairy sources are satisfactory. Technological and functional properties, besides the viability of the probiotics used in fermented products of non-dairy origin are extremely important to get a competitive advantage in the world market. The functional attributes of dairy and non-dairy probiotic products are further enhanced by adding prebiotics such as galacto-oligosaccharide, fructo-oligosaccharide and inulin.

Probiotic attributes of Lactobacillus fermentum isolated from human feces and dairy products

The objective of this study was to characterize native Lactobacillus fermentum isolates for their probiotic attributes. Accordingly, 12 L. fermentum isolates selected from indigenous fermented dairy products and infant fecal samples were evaluated for their probiotic properties by in vitro and PCR methods. The cultures exhibited high tolerance to acid and bile as well as survival in simulated transit fluids (above 70 %). Cell surface hydrophobicity was in the range of 0.55-57.69 % for xylene and 0.45-77.12 % for hexadecane, whereas auto-aggregation ranged between 9 and 62 %. Isolates exhibited efficient binding to mucin and fibronectin, bile salt hydrolase activity, cholesterol assimilation (49-76 %), and radical scavenging activity (37-77 %). The isolates demonstrated antibacterial activity against Listeria monocytogenes Scott A and Micrococcus luteus ATCC 9341. Molecular fingerprinting and identification of the isolates were achieved by PCR with GTG5 as well as 16S rRNA, phenylalanyl-tRNA synthetase alpha subunit (pheS), and RNA polymerase alpha subunit (rpoA) genes. This revealed the genomic diversity of the isolates from the two sources. Gene-specific amplification of probiotic marker genes was attained by PCR-based methods, and resultant products were sequenced. Multiple sequence alignment of the probiotic marker genes using bioinformatics revealed similarity to completely sequenced genomes of L. fermentum CECT 5716 and IFO 3956 with a few variations in mucin-binding protein gene sequences. Isolates designated as L. fermentum MCC 2759 and L. fermentum MCC 2760 showed the best probiotic attributes with high survival in simulated gastrointestinal fluids, in vitro adhesion, cholesterol reduction, and high antioxidative potential. Thus, these cultures could be potential probiotic candidates for application as functional foods.

Optimization of conditions for probiotic curd formulation by Enterococcus faecium MTCC 5695 with probiotic properties using response surface methodology

Enterococcus faecium MTCC 5695 possessing potential probiotic properties as well as enterocin producing ability was used as starter culture. Effect of time (12-24 h) and inoculum level (3-7 % v/v) on cell growth, bacteriocin production, antioxidant property, titrable acidity and pH of curd was studied by response surface methodology (RSM). The optimized conditions were 26.48 h and 2.17%v/v inoculum and the second order model validated. Co cultivation studies revealed that the formulated product had the ability to prevent growth of foodborne pathogens that affect keeping quality of the product during storage. The results indicated that application of E. faecium MTCC 5695 along with usage of optimized conditions attributed to the formation of highly consistent well set curd with bioactive and bioprotective properties. Formulated curd with potential probiotic attributes can be used as therapeutic agent for the treatment of foodborne diseases like Traveler's diarrhea and gastroenteritis which thereby help in improvement of bowel health.

Performance evaluation of bulk freeze dried starter cultures of dahi and yoghurt along with probiotic strains in standardized milk of cow and buffalo

Performance of bulk freeze dried (BFD) cultures of dahi (D) and yoghurt (Y) either with or without probiotic cultures (AB -Lactobacillus acidophilus and Bifidobacterium bifidum) in standardized milk of cow and buffalo was evaluated. In buffalo milk, significantly (p < 0.05) low viable count of probiotic culture combination of dahi cultures (DAB) over non probiotic combination (D) was noticed; whereas, difference in counts of yoghurt culture combinations Y and YAB was not significant. The culture activity of D and DAB was similar in both types of milk, however, the volatile acidity (VA) produced by combination D was higher (32.5 ml/50 g sample) in buffalo milk than in cow milk (29.2 ml/50 g sample). Whereas, DAB produced very low amount of VA (16 ml/50 g sample) both in cow and buffalo milk. The diacetyl and tyrosine contents produced by either D or DAB in cow or buffalo milk were in the same order. Although Y and YAB produced slightly more VA in buffalo milk than in cow milk, significant change in the performance of yoghurt cultures (Y or YAB) both in cow and buffalo milk was not noticed. However, the VA and acetaldehyde produced by YAB either in cow and buffalo milk was higher than that by combination Y. Addition of probiotic cultures significantly enhanced the production of acetaldehyde content in both types of milk. Difference in tyrosine content in yoghurt made either with cow or buffalo milk was not significant. Overall, the present study indicated that the BFD cultures can be used to prepare dahi or yoghurt either from cow or buffalo milk, without affecting the biochemical profile of these products.