•Short peptides, peptide analogues, and flavonoids were synthesized in the beverage.•Flavonoid glycosides and soyasaponins were degraded in the beverage.•Soy glycerophosphoserines (PS) and ...glycerophosphoethanolamines (PE) were synthesized.•The beverage showed high ACE inhibitory and DPPH radical scavenging activity.•Lactobacillus, S. cerevisiae, Pichia membranifaciens were among the main microbiome.
Integrated metabolomic and metagenomic techniques were used to study the metabolite dynamics and phytochemistry of a soy whey-based beverage bio-transformed by water kefir consortium. The UPLC- MS/MS and HPLC-ESI-MS metabolite quantification and the OPLS-DA result showed that the kefir consortium induced a significant change in the metabolite composition and altered the phytochemistry of the fermented beverage. Bioactive peptide analogues, flavonoids, and glycerophospholipids including N-acetyl-L-phenylalanine, acetyl-DL-leucine; tephcalostan, wogonin, pelargonin, genistein, daidzein, and glycerophosphoserines (PS), glycerophosphoethanolamines (PE) respectively were synthesized while flavonoid glycosides and soyasaponins were degraded in the novel beverage. Furthermore, the beverage showed high ACE inhibitory and DPPH radical scavenging activity of 92.31% and 87.51% respectively. Lactobacillus, Saccharomyces cerevisiae, and Pichia membranifaciens were the predominant microbial groups in the new beverage as revealed by the metagenomic sequence analysis. The study thus provides discrete data evidence that kefir consortium is a viable starter for transforming soy whey into a bioactive beverage.
Freeze‐dried immobilized kefir culture in cider‐making Nikolaou, Anastasios; Nelios, Grigorios; Kanellaki, Maria ...
Journal of the science of food and agriculture,
June 2020, 2020-Jun, 2020-06-00, 20200601, Letnik:
100, Številka:
8
Journal Article
The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes.
Four dairy foods processing by-products (acid whey ...permeate AWP, buttermilk BM, sweet whey permeate SWP, and sweet whey permeate with added milk fat globule ingredient SWP+MFGM) were fermented for 4 wk and compared with traditional kefir milks for production of novel kefir-like dairy products. Sweet whey permeates and SWP supplemented with 1.5% milk fat globule membrane (MFGM) proved to be the most viable by-products for kefir grain fermentation, exhibiting diverse abundance of traditional kefir microorganisms and positive indicators of bioactive properties. Grain viability was assessed with shotgun metagenomics, texture profile analysis, live cell counts, and scanning electron microscopy. Assessed bioactivities of the kefir-like products included antibacterial, antioxidant, potential anticancerogenic properties, and membrane barrier effects on human colorectal adenocarcinoma Caco-2 cells. All kefir grains were most abundant in Lactobacillus kefiranofaciens when analyzed with shotgun metagenomics. When analyzed with live cell counts on selective media, AWP kefir-like product had no countable Lactococcus spp., indicating suboptimal conditions for kefir grain microbiota survival and application for fermented dairy starter culture bacterium. Live cell counts were affirmed with kefir grain surface scanning electron microscopy images. The SWP treatment had the most adhesive kefir grain surface, and SWP+MFGM had the largest exopolysaccharide yield from grain extraction. All kefir and kefir-like products were able to achieve a 6-log reduction against Listeria innocua and Escherichia coli. Traditional milk kefirs had the highest antioxidant capacity for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid; ABTS) assay. The AWP formulation had a significantly higher DPPH antioxidant activity compared with the other kefir and kefir-like products, and SWP had the lowest Trolox equivalence concentration in the ABTS assay. Sweet whey and supplemented milk fat sweet whey had upregulation of Cldn-1 and Ocln-1 gene expression, which correspond with a significant increase in transepithelial electrical resistance.
Nowadays, the interest in the consumption of healthy foods has increased as well as the homemade preparation of artisanal fermented product. Water kefir is an ancient drink of uncertain origin, which ...has been passed down from generation to generation and is currently consumed practically all over the world. Considering the recent and extensive updates published on sugary kefir, this work aims to shed light on the scientific works that have been published so far in relation to this complex ecosystem. We focused our review evaluating the factors that affect the beverage microbial and chemical composition that are responsible for the health attribute of water kefir as well as the grain growth. The microbial ecosystem that constitutes the grains and the fermented consumed beverage can vary according to the fermentation conditions (time and temperature) and especially with the use of different substrates (source of sugars, additives as fruits and molasses). In this sense, the populations of microorganisms in the beverage as well as the metabolites that they produce varies and in consequence their health properties. Otherwise, the knowledge of the variables affecting grain growth are also discussed for its relevance in maintenance of the starter biomass as well as the use of dextran for technological application.
The current study aimed to determine the bacterial microbiota of five commercial and one traditional kefir beverages consumed in Turkey. In all samples, Firmicutes (93.66%–99.98%) were the most ...abundant filum. Actinobacteria were detected (6.19%) in one commercial sample, and Proteobacteria were detected (5.91%) in the traditional kefir beverage. The dominant family in all commercial kefir beverages was Streptococcaceae (89.12–99.83%), and the most common genus was Lactococcus in three samples and Streptococcus in the other two samples. However, Lactobacillaceae (36.68%) and Streptococcaceae (36.68%) were dominant in traditional kefir. Lactococcus, Streptococcus and Enterococcus were common in all samples.
Preparation of samples for metagenomic and bioinformatic analysis
There is a lack of research on how Tibetan kefir grains fermentation alters the physicochemical properties and biological activity of Lycium barbarum pulp polysaccharides, despite some reports that ...fermentation can affect the structure and activity of plant polysaccharides. This study demonstrated that, through fermentation, the molecular weight of polysaccharides decreased from 25.33 to 15.11 kg/mol while the contents of total sugar and uronic acid increased by 19.11% and 40.38%, respectively. Furthermore, after fermentation, the polysaccharides exhibited an uneven and rough surface along with a reduced number of branched chains and triple helix structures. Tibetan kefir grains fermentation enhanced the antioxidant activity of polysaccharides, which may be attributed to an increase in arabinose, galactose, and uronic acid content and a decrease in polysaccharide molecular weight. This research offers an alternative viewpoint on the potential application of Tibetan kefir grains-fermented Lycium barbarum pulp polysaccharides in functional foods.
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•Lycium barbarum pulp polysaccharides were obtained by separation and purification.•The content of monosaccharides increased after Tibetan kefir grains fermentation.•The structure of polysaccharides was changed by Tibetan kefir grains fermentation.•Fermentation can enhance the antioxidant activity of polysaccharides.
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•Oxytetracycline (OTC) causes severe intestinal damage of zebrafish larvae.•Kefir extract (KE) help to reverse the impaired intestinal motility caused by OTC.•Short-term effect of KE ...mainly reverses intestinal damage at the molecular level.•The short-term effect of KE on morphology of damaged intestine is limited.
The antibiotic oxytetracycline (OTC) can be detected in contemporary natural aquatic environments and has been implicated in causing intestinal damage in humans exposed to OTC-contaminated food or water. The irreversible damage caused by high concentrations of OTC to the intestine suggests that treatment through dietary means could still be necessary. This study proved the effectiveness of kefir extract (KE) in reversing intestinal damage caused by oxytetracycline (OTC) exposure. Following a 24-hour KE treatment subsequent to OTC exposure from 3 to 8 days post-fertilization of zebrafish larvae, molecular-level and microbiomic assessments revealed significant improvements. These included reduced expression of proinflammatory factors (IL-8 and IL-1β), increased antioxidant levels, and reversed unhealthy distribution of intestinal microbiota. Furthermore, KE supplementation showed potential in enhancing intestinal motility in the experiment of Nile red staining and fluorescent microbead transit. However, histological analysis showed that this short-term treatment with KE only partially reversed the intestinal morphological changes induced by OTC, suggesting that a longer treatment period might be necessary for complete restoration.
Kefir is a homemade, natural fermented product comprised of a probiotic bacteria and yeast complex. Kefir consumption has been associated with many advantageous properties to general health, ...including as an antioxidative, anti-obesity, anti-inflammatory, anti-microbial, and anti-tumor moiety. This beverage is commonly found and consumed by people in the United States of America, China, France, Brazil, and Japan. Recently, the consumption of kefir has been popularized in other countries including Malaysia. The microflora in kefir from different countries differs due to variations in culture conditions and the starter media. Thus, this study was aimed at isolating and characterizing the lactic acid bacteria that are predominant in Malaysian kefir grains via macroscopic examination and 16S ribosomal RNA gene sequencing. The results revealed that the Malaysian kefir grains are dominated by three different strains of Lactobacillus strains, which are Lactobacillus harbinensis, Lactobacillusparacasei, and Lactobacillus plantarum. The probiotic properties of these strains, such as acid and bile salt tolerances, adherence ability to the intestinal mucosa, antibiotic resistance, and hemolytic test, were subsequently conducted and extensively studied. The isolated Lactobacillus spp. from kefir H maintained its survival rate within 3 h of incubation at pH 3 and pH 4 at 98.0 ± 3.3% and 96.1 ± 1.7% of bacteria growth and exhibited the highest survival at bile salt condition at 0.3% and 0.5%. The same isolate also showed high adherence ability to intestinal cells at 96.3 ± 0.01%, has antibiotic resistance towards ampicillin, penicillin, and tetracycline, and showed no hemolytic activity. In addition, the results of antioxidant activity tests demonstrated that isolated Lactobacillus spp. from kefir G possessed high antioxidant activities for total phenolic content (TPC), total flavonoid content (TFC), ferric reducing ability of plasma (FRAP), and 1,1-diphenyl-2-picryl-hydrazine (DPPH) assay compared to other isolates. From these data, all Lactobacillus spp. isolated from Malaysian kefir serve as promising candidates for probiotics foods and beverage since they exhibit potential probiotic properties and antioxidant activities.
In this study, we have investigated the bacterial and fungal community compositions in five Tibetan kefir grains (grain group) and five related kefir milks (milk group) via a combination of ...high-throughput sequencing technology and comparative bioinformatics analyses. According to the high-throughput sequencing technology, a total of 2,099,928 and 1,978,404 high-quality valid sequences were obtained from the bacterial and fungal communities of ten analyzed samples, respectively. Sequences were analyzed from family to species level for microbial community composition analysis. At the species level, a total of thirteen bacterial species and forty-six fungal species were detected, among which eight bacterial species and six fungal species with the relative abundances higher than 0.05% in at least one sample were further applied for the comparative bioinformatics analyses in the microbial community composition between the grain group (TKG1-5) and milk group (TK1-5), revealing that the fungal community compositions of grain and milk groups were similar; however, considerable differences were found in the bacterial community composition between the grain and milk groups. Both differences and similarities in the microbial community composition between the grain and milk groups were clearly revealed.
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•High-throughput sequencing technology was applied.•Bacterial community compositions of Tibetan kefir grains and milks were revealed.•Fungal community compositions of Tibetan kefir grains and milks were revealed.•Differences in the microbial community between grains and milks were revealed.
The present study compared bacterial and fungal diversity of kefir beverages produced using milk (MK) or sugared water (WK) as propagation matrices and grains from the cities of Curitiba (CU) or ...Salvador (SA), Brazil, by sequencing the complete set of RNA transcripts produced in four products. In Brazil, milk and sugared water are used as matrices to propagate kefir grains. In all beverages, the bacterial community was composed of Lactobacillaceae and Acetobacteraceae. Saccharomycetaceae was the yeast family more abundant in WK, and Dipodascaceae and Pichiaceae in MK. Regarding KEGG mapping of functional orthologs, the four kefir samples shared 70% of KO entries of yeast genes but only 36% of bacterial genes. Concerning main metabolic processes, the relative abundance of transcripts associated with metabolism (energy metabolism) and environmental information processing (membrane transport) had the highest water/milk kefir ratio observed in Firmicutes. In contrast, transcripts associated with genetic information processing (protein translation, folding, sorting, and degradation) oppositely had the lowest water/milk ratios. Concluding, milk and water kefir have quite different communities of microorganisms. Still, the main mapped functional processes are similar, with only quantitative variation in membrane transport and energy acquisition in the water kefir and protein synthesis and turnover in the milk kefir.
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