Optimization of cholesterol removal, growth and fermentation patterns of Lactobacillus acidophilus ATCC 4962 in the presence of mannitol, fructo-oligosaccharide and inulin: a response surface methodology approach

Aims: To optimize cholesterol removal by Lactobacillus acidophilus ATCC 4962 in the presence of prebiotics, and study the growth and fermentation patterns of the prebiotics. Methods and Results: Lactobacillus acidophilus ATCC 4962 was screened in the presence of six prebiotics, namely sorbitol, mannitol, maltodextrin, hi-amylose maize, fructo-oligosaccharide (FOS) and inulin in order to determine the best combination for highest level of cholesterol removal. The first-order model showed that the combination of inoculum size, mannitol, FOS and inulin was best for removal of cholesterol. The second-order polynomial regression model estimated the optimum condition of the factors for cholesterol removal by L. acidophilus ATCC 4962 to be 2.64% w/v inoculum size, 4.13% w/v mannitol, 3.29% w/v FOS and 5.81% w/v inulin. Analyses of growth, mean doubling time and short-chain fatty acid (SCFA) production using quadratic models indicated that cholesterol removal and the production of SCFA were growth associated. Conclusions: Optimum cholesterol removal was obtained from the fermentation of L. acidophilus ATCC 4962 in the presence of mannitol, FOS and inulin. Cholesterol removal and the production of SCFA appeared to be growth associated and highly influenced by the prebiotics. Significance and Impact of the Study: Response surface methodology proved reliable in developing the model, optimizing factors and analysing interaction effects. The results provide better understanding on the interactions between probiotic and prebiotics for the removal of cholesterol

Use of Dry Whey and Lactose Hydrolysis in Yogurt Bases

Yogurt is one of the oldest and most traditional fermented dairy products. Since early times it has been an important food item of the people in the Middle East. Except for its refreshing taste and wholesomeness as a food, no special virtues were claimed for it until early in the 20th century when the bacteriologist, Elie Metchnikoff, who shared a Nobel Prize in 1908, concluded from his studies on the effect of lactic acid bacteria of the digestive tract, that yogurt arrests putrefaction in the intestinal tract and thus might be beneficial to health (55). Attempts to popularize yogurt in the United States (US) and Canada were first successful in the 1940\u27s. In 1955, the total production of yogurt in the US was only 17,000,000 lb, whereas by l980 the production increased -to 589,000,000 lb. On a per capita basis, consumption rose from .2 lb in 1960 to 2.67 lb in 1980 (64). The future looks bright for the yogurt industry, particularly in view of the fact that per-capita consumption in the US is still far below that of most European countries; annual yogurt consumption per person in 1977 was 1.2 kg in the US compared to 14.9 kg in the Netherlands, 14.2 kg in Denmark, 12.2 kg in Switzerland, and 8.0 kg in France (103). Whey is plentiful. According to Delaney (19), approximately 16,000,000 tons of whey are produced in the US yearly. About 80% of the whey is from whole milk cheese and 20% from cottage cheese manufacture. It is estimated that just over one-half of this whey is used and the remainder is disposed as waste (6). In the middle ages, whey was utilized as a pharmaceutical drug, as a skin balm, and in cattle feed; but rarely was it used as a food for humans. As the cheese industry grew, production of an increasing volume of byproduct fluid whey, for which there was little demand, accompanied it. Strong new regulations prohibit dumping of whey into streams, rivers, and even into municipal sewerage systems because of its high biological oxidation demand (53). The dairy industry is always interested in use of new and different ingredients that are lower in cost and do not affect quality of product. A great deal of research has been aimed toward promoting proper utilization of whey; but it has not been nearly enough, arid utilization of whey remains perhaps the most serious problem facing the dairy -industry worldwide. One must therefore admire the many efforts in research and manufacturing aimed at making something consumable and marketable, if not profitable, from whey. The use of whey in yogurt and other dairy products has been limited heretofore, because of its effect on the quality of the finished product. However, in the current decade research has been done on the feasibility of replacing nonfat dry milk with dry whey in yogurt and frozen desserts. Use of lactase (e-D-galactosidase or E. C. 3. 2. 1. 23 β-D-galactoside galactohydrolase) to hydrolyze lactose, the major carbohydrate of milk, into its constituent monosaccharides glucose and galactose prior to product manufacture has received considerable attention during the past decade. Applications for the food industry are readily apparent; one application is preparation of low lactose dairy products intended for use by lactose sensitive individuals. The objectives of this research were: 1) to determine the acceptability of yogurts made with reconstituted nonfat dry milk bases, having 50 or 75% hydrolysis of the total lactose available in the mixes along with replacement of 25 or 50% of the nonfat dry milk content with sweet dry whey; 2) to ascertain economy achieved by use of dry whey, which costs less than nonfat dry milk, and use of less sugar in hydrolyzed batches since the products of lactose hydrolysis are sweeter than lactose per se; and 3) to ascertain whether enzymatic hydrolysis of lactose to its component simple sugars would make possible the use of greater percentages of dry whey in yogurt formulas without adverse effects on flavor and/or other properties of the yogurt

De 'Europese markt voor vennootschapsrecht': een (her)evaluatie van het vennootschapsrechtelijk harmonisatieprogramma

The survival of probiotic microorganisms including Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus rhamnosus and Bifidobacterium spp. was evaluated in yoghurt and freeze-dried yoghurt after processing and storage. The effectiveness of microencapsulating probiotic organisms as well as adding cryoprotectants and prebiotics in improving their viability was also investigated. The viability of Bifidobacterium infantis 17930 and L. rhamnosus GG was reduced by 0.07 log, while that of L. casei 1520 and Bifidobacterium longum 1941 was reduced by 0.28 and 0.39 log, respectively. There was a 7% improvement in the viability of L. casei 1520 when cryoprotectant 'Unipectine™ RS 150' was added at 2.5% (w/v). The prebiotic 'Raftilose®P95' when added at 1.5% w/v to yoghurt improved the viability of the combined selected probiotic organisms by 1.42 log during four weeks of storage at 4°C. Microencapsulation with alginate improved viability of combined selected probiotic organisms by 0.31 log in freeze-dried yoghurt stored at 21°C.link_to_subscribed_fulltex

Fermentation of calcium-fortified soya milk does not appear to enhance acute calcium absorption in osteopenic post-menopausal women

Ageing women may choose to drink soya milk to reduce menopausal symptoms. As fermentation enriches soya milk with isoflavone aglycones, its beneficial qualities may improve. To reduce osteoporotic risk, however, soya milk must be Ca enriched, and it is not known how fermentation affects Ca bioavailability. A randomised crossover pilot study was undertaken to compare the Ca absorption of fortified soya milk with that of fermented and fortified soya milk in twelve Australian osteopenic post-menopausal women. The fortified soya milk was inoculated with Lactobacillus acidophilus American Type Culture Collection (ATCC) 4962 and fermented for 24 h at 37°C. Ca absorption from soya milk samples was measured using a single isotope radiocalcium method. Participants had a mean age of 54·8 (sd 12·3) years, with mean BMI of 26·5 (sd 5·5) kg/m2 and subnormal to normal serum 25-hydroxyvitamin D (mean 62·5 (sd 19·1) nmol/l). Participants consumed 185 kBq of 45Ca in 44 mg of Ca carrier. The mean fractional Ca absorption (α) from soya milk and fermented soya milk was 0·64 (sd 0·23) and 0·71 (sd 0·29), respectively, a difference not of statistical significance (P = 0·122). Although fermentation of soya milk may provide other health benefits, fermentation had little effect on acute Ca absorption

Transcriptomic Insights Into the Growth Phase- and Sugar-Associated Changes in the Exopolysaccharide Production of a High EPS-Producing Streptococcus thermophilus ASCC 1275

In a previous study, incorporation of high exopolysaccharide (EPS) producing dairy starter bacterium Streptococcus thermophilus ASCC 1275 was found to improve functionality of low fat mozzarella cheese and yogurt. This bacterium in its eps gene cluster has a unique pair of chain length determining genes, epsC- epsD, when compared to other sequenced S. thermophilus strains. Hence, the aim of this study was to understand the regulatory mechanism of EPS production in this bacterium using transcriptomic analysis to provide opportunities to improve the yield of EPS. As sugars are considered as one of the major determinants of EPS production, after preliminary screening, we selected three sugars, glucose, sucrose and lactose to identify the EPS producing mechanism of this bacterium in M17 medium. Complete RNA-seq analysis was performed using Illumina HiSeq 2000 sequencing system on S. thermophilus 1275 grown in three different sugars at two-time points, 5 h (log phase) and 10 h (stationary phase) to recognize the genes involved in sugar uptake, UDP-sugar formation, EPS assembly and export of EPS outside the bacterial cell. S. thermophilus 1275 was found to produce high amount of EPS (∼430 mg/L) in sucrose (1%) supplemented M17 medium when compared to other two sugars. Differential gene expression analysis revealed the involvement of phosphoenolpyruvate phosphotransferase system (PEP-PTS) for glucose and sucrose uptake, and lacS gene for lactose uptake. The pathways for the formation of UDP-glucose and UDP-galactose were highly upregulated in all the three sugars. In the presence of sucrose, eps1C1D2C2D were found to be highly expressed which refers to high EPS production. Protein homology study suggested the presence of Wzx/Wzy-dependent EPS synthesis and transport pathway in this bacterium. KEGG pathway and COG functional enrichment analysis were also performed to support the result. This is the first report providing the transcriptomic insights into the EPS production mechanism of a common dairy bacterium, S. thermophilus

The potential application of probiotics and prebiotics for the prevention and treatment of COVID-19

10.1038/s41538-020-00078-9npj Science of Food411

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Antimicrobial effects of probiotic bacteria against selected species of yeasts and moulds in cheese-based dips

The antimicrobial properties of selected probiotic bacteria against Aspergillus niger, Penicillium roqueforti, Fusarium spp., Candida albicans and Saccharomyces cerevisiae were examined. Well diffusion and spot and streak methods showed strong inhibition effect of probiotic bacteria and their metabolites against moulds and minimal effect against yeasts. Among the moulds species tested, the inhibitory effect was strongest against Fusarium spp., moderate against Penicillium roqueforti and minimal against A. niger. All strains of Lactobacillus rhamnosus and L. paracasei subsp. paracasei showed maximum inhibitory effect. When probiotic bacteria and yeasts and moulds were co-cultured in broth media, strains of L. rhamnosus showed maximum inhibitory effect, whereas L. paracasei subsp. paracasei, L. acidophilus, Bifidobacterium animalis and Propionibacterium showed moderate inhibitory effect against C. albicans. Saccharomyces cerevisiae was minimally controlled by probiotic bacteria. Pre-grown probiotic bacterial culture metabolites controlled yeasts and moulds more effectively than their freeze-dried or frozen forms. Adding metabolites of probiotic bacteria (5% w/w) showed an effective control against A. niger, Fusarium spp. and C. albicans during the shelf life of 10 weeks at 4 �C and no colonies of yeasts and moulds were formed on the surface of the dip