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The principal objective of this study was to isolate and identify the microorganisms present in commercial kefir grains, a novel kefir-fermented coconut water (CWK) and a novel coconut water kefir-fermented sourdough using phenotypic identification and Sanger sequencing and examine the microbial diversity of CWK and CWK-fermented sourdough throughout the fermentation process using the MiSeq Illumina sequencing method. The phenotypic characterisation based on morphology identified ten isolates of LAB, five AAB and seven yeasts from kefir (K), CWK and CWK-fermented sourdough (CWKS). The results confirm the presence of the LAB species Limosilactobacillus fermentum, Lactobacillus. plantarum, L. fusant, L. reuteri and L. kunkeei; the AAB species Acetobacter aceti, A. lovaniensis and A. pasteurianus; and the yeast species Candida kefyr, Rhodotorula mucilaginosa, Saccharomyces cerevisiae, C. guilliermondii and C. colliculosa. To the best of our knowledge, the identification of Rhodotorula from kefir is being reported for the first time. This study provides important insights into the relative abundances of the microorganisms in CWKS. A decrease in pH and an increase in the titratable acidity for CWK- and CWK-fermented sourdough corresponded to the increase in D- and L-lactic acid production after 96 h of fermentation. Significant reductions in the pHs of CWK and CWKS were observed between 48 and 96 h of fermentation, indicating that the kefir microorganisms were able to sustain highly acidic environments. There was also increased production of L-lactic acid with fermentation, which was almost twice that of D-lactic acid in CWK. [ABSTRACT FROM AUTHOR]

A global epidemiological shift has been observed in recent decades, characterized by an increase in age-related disorders, notably non-communicable chronic diseases, such as type 2 diabetes mellitus, cardiovascular and neurodegenerative diseases, and cancer. An appreciable causal link between changes in the gut microbiota and the onset of these maladies has been recognized, offering an avenue for effective management. Kefir, a probiotic-enriched fermented food, has gained significance in this setting due to its promising resource for the development of functional or value-added food formulations and its ability to reshape gut microbial composition. This has led to increasing commercial interest worldwide as it presents a natural beverage replete with health-promoting microbes and several bioactive compounds. Given the substantial role of the gut microbiota in human health and the etiology of several diseases, we conducted a comprehensive synthesis covering a total of 33 investigations involving experimental animal models, aimed to elucidate the regulatory influence of bioactive compounds present in kefir on gut microbiota and their potential in promoting optimal health. This review underscores the outstanding nutritional properties of kefir as a central repository of bioactive compounds encompassing micronutrients and amino acids and delineates their regulatory effects at deficient, adequate, and supra-nutritional intakes on the gut microbiota and their broader physiological consequences. Furthermore, an investigation of putative mechanisms that govern the regulatory effects of kefir on the gut microbiota and its connections with various human diseases was discussed, along with potential applications in the food industry. [ABSTRACT FROM AUTHOR]

Probiotics are known for their health-promoting resources and are considered as beneficial microorganisms. The current study focuses on the isolation, and on a complete in vitro and in vivo characterization, of yeast and lactic acid bacteria acquired from traditional homemade kefir in order to assess their potentiality as probiotic candidates. In particular, the isolates Pichia kudriavzevii Y1, Lactococcus lactis subsp. hordniae LAB1 and Lactococcus lactis subsp. lactis LAB2 were subjected to in vitro characterization to evaluate their suitability as probiotics. Resistance to acid and bile salts, auto-aggregation, co-aggregation, hydrophobicity, and biofilm production capability were examined, as well as their antioxidant activity. A safety assessment was also conducted to confirm the non-pathogenic nature of the isolates, with hemolysis assay and antibiotic resistance assessment. Moreover, mortality in the invertebrate model Galleria mellonella was evaluated. Current findings showed that P. kudriavzevii exhibited estimable probiotic properties, placing them as promising candidates for functional foods. Both lactic acid bacteria isolated in this work could be classified as potential probiotics with advantageous traits, including antimicrobial activity against enteric pathogens and good adhesion ability on intestinal cells. This study revealed that homemade kefir could be a beneficial origin of different probiotic microorganisms that may enhance health and wellness. [ABSTRACT FROM AUTHOR]

Pumpkin has been reported to be a good probiotic delivery vehicle, but it has a short shelf life, is susceptible to enzymatic browning, and prone to microbial spoilage. Pumpkin could be transformed into a value-added beverage through the fermentation by LAB. In the present work, the probiotic viability, physicochemical, antioxidative, antihyperglycemic, and sensory properties of Lactobacillus mali-fermented pumpkin drink (FPD) during eight weeks of refrigerated storage at 4°C were investigated. There were significant reductions (p < 0.05) in colour, pH, texture characteristics, and antioxidant properties after four weeks of storage. FPD exhibited total phenolic content ranging from 83.75 to 90.75 mg GAE/mL, total flavonoid content ranging from 47.01 to 50.01 mg QE/mL, FRAP reducing power ranging from 160.76 to 169.76 µmol Trolox equivalent/mL, and DPPH scavenging activity ranging from 52 to 54.56% during storage. FPD's total soluble solids decreased (p < 0.05) from 0.60 to 0.02 °Brix, while concentrations of ethanol (0.62 to 1.2%, v/v), lactic acid (0.03 to 0.11 g/L), and acetic acid (0.02 to 0.18 g/L) significantly increased (p < 0.05) over eight weeks of storage. L. mali strain within FPD maintained its viability (p > 0.05) under simulated gastrointestinal conditions, with 8 - 9.1 log CFU/mL for 28 days at 4°C. FPD retained up to 90% a-glucosidase enzyme inhibition throughout the 28 days storage period. Sensory evaluation showed that FPD's attributes remained unchanged (p > 0.05) during the initial four weeks of storage, with an overall acceptability score ranging from 6.56 to 6.88. In conclusion, FPD remained stable in terms of physicochemical, antioxidative, and sensory properties, as well as probiotic viability and anti-hyperglycaemic effects during 28 days of refrigerated storage. This highlights FPD's potential as a functional beverage, presenting an innovative method to utilise pumpkin as an effective probiotic carrier. [ABSTRACT FROM AUTHOR]

Kefir grains are symbiotic microbiota starters in the production of dairy products such as fermented milk, kefir. In recent decades, microbial symbiosis in kefir grains and its role in fermentation have attracted a lot of attention. This study aimed to obtain novel kefirs with different characteristics by "stimulating" kefir grains with juices of Actinidia chinensis, Solanumly copersicum, Daucus carrot, and Lactuca sativa, respectively, before being used as starter cultures for kefir fermentation. Then, compositions of the predominant microbiota in novel kefirs were determined. These novel kefirs showed changes in their physiochemical characteristics and enhanced antimicrobial activities against Shigella dysenteriae, Candida albicans, Staphylococcus aureus, Serratia marcescens, and Escherichia coli. Therefore, preprocessing of kefir grains with natural substrates could be a feasible strategy in the production of novel kefirs with different flavors and various health benefits. [ABSTRACT FROM AUTHOR]

The kefir‐based smoothies with kale and spinach were designed as a ready‐to‐drink and innovative functional snack. Microbiological, physicochemical, as well as pre‐ and postgastrointestinal total antioxidant capacity (TAC; CUPRAC, DPPH, and FRAP) analyses were conducted. It was determined that the kefir‐based smoothies with vegetables had higher ash, carbohydrate, and dietary fiber values. Fructose and glucose contents of smoothy with kale were high, while smoothy with spinach included high sucrose and maltose. The microbiology results revealed that kefir‐based vegetable smoothies had minimum Lactobacillaceae viability (>log 7 cfu g−1) for the required functional effect after 14‐day storage. Moreover, the addition of kale significantly increased (p <.01) the level of initial TAC (CUPRAC, DPPH, and FRAP) and total phenolic content (TPC) values. After in vitro gastric digestion analysis, smoothie with spinach demonstrated higher TAC and TPC values and the control sample had higher TAC and TPC values compared with a predigestion step. It was found that in vitro intestinal DPPH values were higher for the sample with spinach samples, while the sample with kale had the highest FRAP values. It was also found that the bioaccessibility indexes of plain kefir were determined to be the highest in both in vitro gastric and intestinal procedures. The present study provided novel insights into the in vitro digestion properties of kefir fortified with vegetables. Nevertheless, further studies are needed to identify the functional properties of the milk and plant matrices mixture using in vitro and in vivo trials. [ABSTRACT FROM AUTHOR]

This study compared flavored kefir (KFR) and flavored milk (MLK) as a recovery drink in endurance master athletes. Using a randomized, placebo-controlled, non-blinded crossover design, 11 males and females completed three testing visits whilst acutely ingesting either KFR, MLK, or water as a placebo (PLA). KFR supplementation occurred for 14 days before the KFR-testing day, followed by a 3-week washout period. Testing visits consisted of an exhausting-exercise (EE) bout, a 4-h rest period where additional carbohydrate feeding was provided, and a treadmill 5 km time trial (TT). The Gastrointestinal Symptom Rating Scale (GSRS) survey was assessed at four timepoints. Blood was collected at baseline and after the TT and was analyzed for I-FABP levels. No significant difference (PLA: 33:39.1 ± 6:29.0 min, KFR: 33:41.1 ± 5:44.4 min, and MLK: 33:36.2 ± 6:40.5 min, p = 0.99) was found between the groups in TT performance. The KFR GSRS total score was significantly lower than the PLA after EE (p = 0.005). No differences in I-FABP were observed between conditions. In conclusion, acute KFR supplementation did not impact TT performance or I-FABP levels but may have reduced subjective GI symptoms surrounding exercise when compared to MLK or PLA. [ABSTRACT FROM AUTHOR]

ABSTRACT Have you ever deeply considered the intersections between research and education, particularly for second-level students? Traditionally, the convergence of these two realms is most often noted when considering the integration of research findings into educational practices or the involvement of, typically a small number, of students in research activities. While these practices have demonstrated efficacy, the fields of scientific research and education are evolving rapidly, necessitating a reevaluation of how we can optimize their convergence. In our discourse, we delve into these evolving trends, uncover the potential for greater integration, and, ultimately, enhance outcomes using the citizen science initiative Kefir4All as an illustrative example.

Kefir is a fermented dairy beverage made from milk and kefir grains containing yeast and bacteria. This publication describes how kefir is made and its potential health effects for consumers. Written by Julia R. Skinner, and published by the UF/IFAS Food Science and Human Nutrition Department, July 2024.

IntroductionKefir beverage has beneficial microorganisms that have health-giving properties; therefore, they have a good potential to be probiotic. This study evaluated the probiotic potential, technological, and safety characteristics of Enterococcus faecalis, Lactococcus lactis, and Pichia fermentans isolated from traditional kefir beverages.MethodFirst, isolates were evaluated in terms of resistance to acid, alkali, bile salts, trypsin, and pepsin of the gastrointestinal tract. The auto-aggregation and co-aggregation ability of isolates were measured using spectrophotometry. Antimicrobial activities were assayed against important food-borne pathogens using the agar well diffusion method. Moreover, gamma-aminobutyric acid (GABA) production was investigated by thin-layer chromatography (TLC).ResultAmong the isolates, P. fermentans had an 85% total survival rate, but its amount reached below 6 log CFU/ml which is considered non-resistant, and it showed the highest auto-aggregation (74.67%). Moreover, only L. lactis showed antimicrobial activity and had the highest co-aggregation with E. coli PTCC 1338 (54.33%) and L. monocytogenes ATCC 7644 (78%). Finally, an evaluation of the technological and safety characteristics of the strains showed that the strains produced GABA and were safe.DiscussionAlthough the isolates were not resistant to the gastrointestinal tract, their supernatant contained valuable natural compounds, including antioxidants, GABA, and antimicrobials, which can be used to produce functional foods and medicines. In addition, other approaches, such as increasing the initial number of strains, using foods as carriers of isolates, and encapsulating the isolates, can effectively increase the survivability of isolates in the gastrointestinal tract.

Abstract Background Dysbiosis of the gut microbiome is frequent in the intensive care unit (ICU), potentially leading to a heightened risk of nosocomial infections. Enhancing the gut microbiome has been proposed as a strategic approach to mitigate potential adverse outcomes. While prior research on select probiotic supplements has not successfully shown to improve gut microbial diversity, fermented foods offer a promising alternative. In this open-label phase I safety and feasibility study, we examined the safety and feasibility of kefir as an initial step towards utilizing fermented foods to mitigate gut dysbiosis in critically ill patients. Methods We administered kefir in escalating doses (60 mL, followed by 120 mL after 12 h, then 240 mL daily) to 54 critically ill patients with an intact gastrointestinal tract. To evaluate kefir’s safety, we monitored for gastrointestinal symptoms. Feasibility was determined by whether patients received a minimum of 75% of their assigned kefir doses. To assess changes in the gut microbiome composition following kefir administration, we collected two stool samples from 13 patients: one within 72 h of admission to the ICU and another at least 72 h after the first stool sample. Results After administering kefir, none of the 54 critically ill patients exhibited signs of kefir-related bacteremia. No side effects like bloating, vomiting, or aspiration were noted, except for diarrhea in two patients concurrently on laxatives. Out of the 393 kefir doses prescribed for all participants, 359 (91%) were successfully administered. We were able to collect an initial stool sample from 29 (54%) patients and a follow-up sample from 13 (24%) patients. Analysis of the 26 paired samples revealed no increase in gut microbial α-diversity between the two timepoints. However, there was a significant improvement in the Gut Microbiome Wellness Index (GMWI) by the second timepoint (P = 0.034, one-sided Wilcoxon signed-rank test); this finding supports our hypothesis that kefir administration can improve gut health in critically ill patients. Additionally, the known microbial species in kefir were found to exhibit varying levels of engraftment in patients’ guts. Conclusions Providing kefir to critically ill individuals is safe and feasible. Our findings warrant a larger evaluation of kefir’s safety, tolerability, and impact on gut microbiome dysbiosis in patients admitted to the ICU. Trial registration NCT05416814; trial registered on June 13, 2022.

Kefir is a fermented dairy beverage produced by using natural microbiota which mainly contains specific microbial communities such as lactic acid bacteria, yeast and acetic acid bacteria, and it has good flavor and health beneficial functions. However, the formation mechanism of kefir grains is not clear at present, and it is generally believed that the formation of kefir grains is based on bacterial biofilm as the precursor. This paper reviews the microbial diversity of kefir from different regions and the effects of microorganisms in kefir grains on the function and flavor of fermented milk, as well as the microbial interactions and succession during kefir fermentation. The role of biofilm formation in kefir grain formation is also described in order to provide some references for future research on the formation mechanism of kefir grains.

Kefir is a fermented drink produced from the addition of kefir grains to the cultivation substrate, traditionally milk. The microorganism’s composition present in kefir depends on several factors, such as origin and fermentation time. Its composition classifies it as a probiotic, capable of providing health benefits if regularly consumed. Thus, the present study is aimed to evaluate the microbiological count stability of the kefir over the period of 35 days, pH, and nutritional composition, in addition to analyzing the bacterial and fungal microbiota. To produce fermented milk, kefir grains were cultivated in pasteurized whole milk at a ratio of 1:10, and the bacteria and yeast counting was performed by the surface plating method. Total genomic DNA was extracted and 16S rRNA and ITS amplicon libraries were generated for each sample, which was sequenced on the Illumina MiSeq platform. According to the lactic acid bacteria and yeasts count, the evaluated kefir presented probiotic count, and both the centesimal composition and the mean pH values turned up to be appropriate over time, even with small pH variations. The main bacterial genera found in kefir were Lactococcus, Bacteroides, and Prevotellaceae_UCG-001, and Aspergillus, Beauveria, and Saccharomyces were the predominant fungal genera. The results indicate that the minimum microbiological counts of kefir milk are maintained during the analysis period, with a predominance of Lactococcus and Aspergillus genera.

This research aims to determine the best fermentation time to produce optimal buffalo colostrum kefir. Different fermentation times at 12, 24, 36, and 48 hours were used to measure the physicochemical and microbiological characteristics of buffalo colostrum kefir. To produce buffalo colostrum kefir, fermentation process at room temperature (27˚C±1) was used. Viscosity was measured using Ostwald viscometer and Total Dissolved Solid (TDS) was measured digital refractometer. Titratable acidity was analyzed using titration method and pH value was measured using pH meter. Protein content was analyzed using Kjeldahl method and fat content was analyzed using Soxhlet method. The result shows no significant differences (P>0.05) in viscosity which results in a value of 0.92±0.09 to 0.80±0.04 cP. Meanwhile, it shows significant differences (P

ABSTRACTKefir is a popular and indigenous fermented product that possess various health claims. Kefir grains with varied bacteria are utilized as starters for kefir production of popular genra including Lactobacillus, Leuconostoc, Lactococcus, and Acetobacter species. The complex microbial community in kefir produce various bioactive compounds owing to their metabolic activities. Kefir has various functional and therapeutic properties, which include immune system stimulation, lactose intolerance symptoms, cholesterol reduction, anti-carcinogenic and anti-mutagenic qualities. Several studies have shown anticarcinogenic, anti-microbial and synbiotic potential of kefir. Current review highlights the production technology, nutritional, functional and therapeutic potential of kefir. Furthermore, production strategies, kefir characteristics and probiotic potential are the limelight of the current review.

In a world increasingly focused on sustainability and integrated resource use, the revalorisation of horticultural by-products is emerging as a key strategy to minimise food loss and waste while maximising value within the food supply chain. Fermentation, one of the earliest and most versatile food processing techniques, utilises microorganisms or enzymes to induce desirable biochemical transformations that enhance the nutritional value, digestibility, safety, and sensory properties of food products. This process has been identified as a promising method for producing novel, high-value food products from discarded or non-aesthetic fruits and vegetables that fail to meet commercial standards due to aesthetic factors such as size or appearance. Besides waste reduction, fermentation enables the production of functional beverages and foods enriched with probiotics, antioxidants, and other bioactive compounds, depending on the specific horticultural matrix and the types of microorganisms employed. This review explores the current bioprocesses used or under investigation, such as alcoholic, lactic, and acetic acid fermentation, for the revalorisation of fruit and vegetable by-products, with particular emphasis on how fermentation can transform these by-products into valuable foods and ingredients for human consumption, contributing to a more sustainable and circular food system.

Kefir, a fermented milk beverage, is recognized for its potential health benefits, including its cholesterol-lowering properties. This study demonstrated that selected kefir starter cultures, including Lactococcus strains and yeasts, significantly reduce cholesterol-binding capacity under simulated gastrointestinal conditions, underscoring the challenges of probiotic delivery. We compared the performance of these cultures under laboratory conditions (growth broths) and simulated digestive juice models. Lactococcus strains showed significant differences in cholesterol binding between the two environments, highlighting the limitations of relying solely on laboratory testing. Yeast cultures also exhibited greater cholesterol binding in their native broths, but their survival was limited in digestive models. Our findings suggest that effective probiotic formulations should prioritize strains with high cholesterol-binding capacity and robust survival rates throughout the digestive tract. This study provides valuable insights for future research on the mechanisms behind these functionalities and the potential of kefir yeast strains for use in human digestive models. Our results can be used to inform the development of improved probiotic formulations for cholesterol management.

Background: Dysbiosis of the gut microbiome is frequent in the intensive care unit (ICU), potentially leading to a heightened risk of nosocomial infections. Enhancing the gut microbiome has been proposed as a strategic approach to mitigate potential adverse outcomes. While prior research on select probiotic supplements has not successfully shown to improve gut microbial diversity, fermented foods offer a promising alternative. In this open-label phase I safety and feasibility study, we examined the safety and feasibility of kefir as an initial step towards utilizing fermented foods to mitigate gut dysbiosis in critically ill patients. Methods: We administered kefir in escalating doses (60 mL, followed by 120 mL after 12 h, then 240 mL daily) to 54 critically ill patients with an intact gastrointestinal tract. To evaluate kefir's safety, we monitored for gastrointestinal symptoms. Feasibility was determined by whether patients received a minimum of 75% of their assigned kefir doses. To assess changes in the gut microbiome composition following kefir administration, we collected two stool samples from 13 patients: one within 72 h of admission to the ICU and another at least 72 h after the first stool sample. Results: After administering kefir, none of the 54 critically ill patients exhibited signs of kefir-related bacteremia. No side effects like bloating, vomiting, or aspiration were noted, except for diarrhea in two patients concurrently on laxatives. Out of the 393 kefir doses prescribed for all participants, 359 (91%) were successfully administered. We were able to collect an initial stool sample from 29 (54%) patients and a follow-up sample from 13 (24%) patients. Analysis of the 26 paired samples revealed no increase in gut microbial α-diversity between the two timepoints. However, there was a significant improvement in the Gut Microbiome Wellness Index (GMWI) by the second timepoint (P = 0.034, one-sided Wilcoxon signed-rank test); this finding supports our hypothesis that kefir administration can improve gut health in critically ill patients. Additionally, the known microbial species in kefir were found to exhibit varying levels of engraftment in patients' guts. Conclusions: Providing kefir to critically ill individuals is safe and feasible. Our findings warrant a larger evaluation of kefir's safety, tolerability, and impact on gut microbiome dysbiosis in patients admitted to the ICU. Trial registration: NCT05416814; trial registered on June 13, 2022. [ABSTRACT FROM AUTHOR]

Kefir consists of a large number of probiotics, which can regulate or shape the balance of intestinal microbiota, and enhance the host's immune response. Kefir microbiota can shape the mucosal immunity of the body through SCFAs, EPS, polypeptides, lactic acid, and other metabolites and microbial antigens themselves, and this shaping may have time windows and specific pathways. Kefir can regulate antibody SIgA and IL-10 levels to maintain intestinal homeostasis, and its secreted SIgA can shape the stable microbiota system by wrapping and binding different classes of microorganisms. The incidence of intestinal inflammation is closely linked to the development and maturation of intestinal mucosal immunity. Based on summarizing the existing research results on Kefir, its metabolites, and immune system development, this paper proposes to use Kefir, traditional fermented food with natural immune-enhancing components and stable functional microbiota, as an intervention method. Early intervention in the immune system may seize the critical window period of mucosal immunity and stimulate the development and maturation of intestinal mucosal immunity in time. [ABSTRACT FROM AUTHOR]

Due to the distinctive characteristics of probiotics, it is essential to pinpoint strains originating from diverse sources that prove efficacious in addressing a range of pathologies linked to dysfunction of the intestinal barrier. Nine strains of lactic acid bacteria were isolated from two different sources of tepache kefir grains (KAS2, KAS3, KAS4, KAS7, KAL4, KBS2, KBS3, KBL1 and KBL3), and were categorized to the genus Lacticaseibacillus, Liquorilactobacillus, and Lentilactobacillus by 16S rRNA gene. Kinetic behaviors of these strains were evaluated in MRS medium, and their probiotic potential was performed: resistance to low pH, tolerance to pepsin, pancreatin, bile salts, antibiotic resistance, hemolytic activity, and adhesion ability. KAS7 strain presented a higher growth rate (0.50 h-1) compared with KAS2 strain, who presented a lower growth rate (0.29 h-1). KBS2 strain was the only strain that survived the in vitro stomach simulation conditions (29.3%). Strain KBL1 demonstrated significantly higher viability (90.6%) in the in vitro intestine simulation conditions. Strain KAS2 demonstrated strong hydrophilic character with chloroform (85.6%) and xylol (57.6%) and a higher percentage of mucin adhesion (87.1%). However, strains KBS2 (84.8%) and KBL3 (89.5%) showed the highest autoaggregation values. In terms of adhesion to the intestinal epithelium in rats, strains KAS2, KAS3 and KAS4 showed values above 80%. The growth of the strains KAS2, KAS3, KAS4, KBS2, and KBL3 was inhibited by cefuroxime, cefotaxime, tetracycline, ampicillin, erythromycin, and cephalothin. Strains KBS2 (41.9% and 33.5%) and KBL3 (42.5% and 32.8%) had the highest co-aggregation values with S. aureus and E. coli. The results obtained in this study indicate that lactic acid bacteria isolated from tepache can be considered as candidates for potentially probiotic bacteria, laying the foundations to evaluate their probiotic functionality in vivo and thus to be used in the formulation of functional foods. [ABSTRACT FROM AUTHOR]

Context Kefir consumption has been associated with immune response modulation, antioxidant, and anti-inflammatory effects. Objective The objective of this systematic review was to investigate the role of kefir against inflammation and the main response mechanisms involved in this process in a murine model. Data Sources The searches were searched in the PubMed, Science Direct, and LILACS databases. Only murine model studies, according to PRISMA guidelines, published in the past 10 years were included. Study Selection Only articles about original and placebo-controlled experiments in murine models used to investigate the anti-inflammatory mechanisms of kefir were considered. Of the articles found, 349 were excluded according to the following criteria: duplicate articles (n = 99), off-topic title and abstract (n = 157), reviews (n = 47), studies in vitro (n = 29), and studies with humans (n = 17). In total, 23 studies were included in this review. Data Extraction Two independently working authors assessed the risk of bias and extracted data from the included studies. Results Kefir consumption had positive effects on inflammation modulation. The main mechanisms involved were the reduction of pro-inflammatory and molecular markers; reduction in inflammatory infiltrate in tissues, serum biomarkers, risk factors for chronic diseases, and parasitic infection; composition and metabolic activity change of intestinal microbiota and mycobiota; activation of humoral and cellular immunity; and modulation of oxidative stress. Conclusions Kefir modulates the immune system in different experimental models, among other secondary outcomes, to improve overall health. The beverage reduces inflammation through the alternation between innate, Th1, and Th2 responses, reducing levels of pro-inflammatory cytokines while increasing those of anti-inflammatory ones. In addition, it also mediates immunomodulatory and protective effects through the numerous molecular biomarkers and organic acids produced and secreted by kefir in the intestinal microbiota. The health-promoting effects attributed to kefir may help in the different treatments of inflammatory, chronic, and infectious diseases in the population. [ABSTRACT FROM AUTHOR]

Water kefir grains (WKGs), the starter used to develop a traditional beverage named water kefir, consist of a symbiotic mixture of probiotics with diverse bioactivities, but little is known about their abilities to remove mycotoxins that have serious adverse effects on humans and animals. This study investigated the ability of WKGs to remove aflatoxin B1 (AFB1), one of the most toxic mycotoxins, under different settings, and determined the mechanism of absorption mediated by WKGs and the effect of WKGs on the toxicity induced by AFB1 and the reduction in AFB1 in cow milk and tea soups. The results showed the WKGs used herein were dominated by Lactobacillus, Acetobacter, Phenylobacterium, Sediminibacterium, Saccharomyces, Issatchenkia, and Kodamaea. HPLC analysis demonstrated that the WKGs effectively removed AFB1 at concentrations ranging from 1 to 5 µg/mL, pH values ranging from 3 to 9, and temperatures ranging from 4 to 45 °C. Additionally, the removal of AFB1 mainly depended on absorption, which was consistent with the Freundlich and pseudo-second-order kinetic models. Moreover, only 49.63% of AFB1 was released from the AFB1-WKG complex after four washes when the release of AFB1 was non-detectable. Furthermore, WKG treatment caused a dramatic reduction in the mutagenicity induced by AFB1 according to an Ames test and reduced more than 54% of AFB1 in cow milk and three tea soups. These results suggested that WKGs can act as a potential bio-absorbent with a high binding ability to detoxify AFB1 in food and feed via a chemical action step and multi-binding sites of AFB1 absorption in a wide range of scenarios. [ABSTRACT FROM AUTHOR]

Background/aim: Scaling and root planing remain inadequate in periodontitis treatment caused by dysbiotic microbial dental plaque. The aim of this clinical trial is to evaluate the effects of probiotics and kefir consumption in initial periodontal therapy (IPT) on oral microbiota composition and treatment outcomes in patients with periodontitis. Materials and methods: The study was carried out in the Gazi University Department of Periodontology, including a sample size of 36 individuals and utilizing a randomized controlled design. Thirty-six patients with periodontitis were randomly allocated to three groups: one receiving probiotic treatment, another receiving kefir, and a third serving as the control group. Obtaining subgingival microbial samples, we recorded plaque, gingival index, bleeding on probing, periodontal pocket depth, and clinical attachment level (periodontal clinical indices) and then performed IPT. For 14 days, patients took either probiotics, kefir, or no supplements. Data for the first and third months were collected using periodontal clinical indices. DNA sequencing was performed to detect Tannerella forsythia, Porphyromonas gingivalis, and Treponema denticola in subgingival plaque samples collected at baseline and three months. Results: Significant differences were observed regarding periodontal clinical indices among groups in the intragroup comparisons. Moreover, levels of Tannerella forsythia were significantly decreased in all groups. Conclusion: Kefir can be administered in addition to IPT, providing results similar to those observed with probiotics. [ABSTRACT FROM AUTHOR]

In this study, the viability of Lactobacillus bacteria in probiotic dairy products sold in Qazvin city within two periods was examined. Eighteen samples of dairy products (yogurt, cheese, and kefir drinks) labeled with probiotics from different brands of various companies in Iran were prepared. Dilutions were prepared appropriately from each sample and inoculated into MRS Bile Agar culture medium as a pour plate culture procedure. After incubation, the colonies were counted and checked to see if the standards of the Iranian National Standardization Organization (INSO) (min 106 CFU/gr) were met. Then, to perform probiotic confirmation tests, each colony characterized different morphological was examined regarding catalase and Gram staining tests. The average count of live Lactobacillus showed that out of eighteen samples of probiotic dairy products, only one sample (5.5%) had the minimum number of bacteria according to INSO. In the yogurt, none of the samples could grow in the bile culture medium. In the cheese, none of the samples had the minimum number of viable bacteria according to the standard. Regarding the kefir drink, only one sample had the minimum number of live bacteria based on the standards, in the first week after the production date. In most of the dairy products labeled as probiotic, the average count of Lactobacillus with the ability to grow in bile, is lower than INSO measurements, which is at least one million bacteria per gram of a product. [ABSTRACT FROM AUTHOR]

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Copyright of Harran Journal of Agricultural & Food Science is the property of Harran University, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fermented beverages have been a constant companion of humans throughout their history. A wide range of products have been developed with time, depending on the availability of raw materials and ambient conditions. Their differentiation was based on the specific characteristics of each product, resulting from the cultivation of different varieties and the variability of environmental conditions and agricultural practices, collectively described by the term 'terroir' that was developed in winemaking. The health benefits that have been associated with their consumption, which include the control of blood pressure and glycemic control, along with immunomodulatory, hypocholesterolemic, hepatoprotective, and antiproliferative activities, directed their re-discovery that occurred over the last few decades. Thus, the dynamics of the microbial communities of fermented beverages during fermentation and storage have been thoroughly assessed. The functional potential of fermented beverages has been attributed to the chemical composition of the raw materials and the bioconversions that take place during fermentation and storage, due to the metabolic capacity of the driving microbiota. Thus, the proper combination of raw materials with certain microorganisms may allow for the modulation of the organoleptic properties, as well as enrichment with specific functional ingredients, enabling targeted nutritional interventions. This plasticity of fermented beverages is their great advantage that offers limitless capabilities. The present article aims to critically summarize and present the current knowledge on the microbiota and functional potential of fermented beverages and highlight the great potential of these products. [ABSTRACT FROM AUTHOR]

The increasing focus on a healthy lifestyle has emphasized a connection between gut microbiome and health. Consumers face the choice between consuming traditional dairy kefirs or more trendy fruit-based fermented drinks. Also, the aim of this study is to determine the similarities and differences theoretically and experimentally based on a higher ratio of grains to make a lower pH-based beverage at different inoculation times and durations. This study also aims to assess acceptability from a sensory perspective. The goal of the research was to make kefir grain-based beverages with a higher number of lactic acid bacteria (LAB) owing to their probiotic impact on the human gut. After analysis, it was found that there was the highest content of LAB in water kefir after 48 h of inoculation. However, consumer acceptance tests found traditional dairy kefir with a 24-h inoculation to be more acceptable. Although both drinks were inoculated in a 1:4 ratio, it is important to note the variations in grain origin as well as the initial composition of the milk–water suspension, which significantly affects the final product. Since the recipe of the kefir determines the benefits of the drink, the onus is on the consumers to decide which fermented drink suits their health condition best. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study was conducted to evaluate the protective effect of milk kefir against NSAID-induced gastric ulcers. Male Swiss mice were divided into three groups: control (Vehicle; UHT milk at a dose of 0.3 mL/100 g), proton pump inhibitor (PPI; lansoprazole 30 mg/kg), and 4% milk kefir (Kefir; 0.3 mL/100 g). After 14 days of treatment, gastric ulcer was induced by oral administration of indomethacin (40 mg/kg). Reactive oxygen species (ROS), nitric oxide (NO), DNA content, cellular apoptosis, IL-10 and TNF-α levels, and myeloperoxidase (MPO) enzyme activity were determined. The interaction networks between NADPH oxidase 2 and kefir peptides 1–35 were determined using the Residue Interaction Network Generator (RING) webserver. Pretreatment with kefir for 14 days prevented gastric lesions. In addition, kefir administration reduced ROS production, DNA fragmentation, apoptosis, and TNF-α systemic levels. Simultaneously, kefir increased NO bioavailability in gastric cells and IL-10 systemic levels. A total of 35 kefir peptides showed affinity with NADPH oxidase 2. These findings suggest that the gastroprotective effect of kefir is due to its antioxidant and anti-inflammatory properties. Kefir could be a promising natural therapy for gastric ulcers, opening new perspectives for future research. [ABSTRACT FROM AUTHOR]

This study aims to increase the functionality of plain kefir by adding citrus fruits. Dry matter ratios of kefir samples ranged from 11.04 % to 11.75 %. The addition of fruit to kefir reduced the milk-fat ratios. The pH values of kefir samples ranged from 3.37 to 4.08 depending on fruit concentration. pH values also ranged from 3.37 to 4.08 depending on fruit concentration. Kefir samples containing grapefruit (37.5 %) had the lowest pH value (3.37) among the kefir samples. The viscosity of kefir samples at 20 rpm and 50 rpm at sliding speed ranged from 0.42 Pa.s to 2.88 Pa.s and from 0.31 to 1.60 Pa.s, respectively. The addition of fruit to plain kefir was reduced its viscosity. DPPH* of samples was between 1.21 and 38.93 % DPPH of samples with citrus fruit were statistically (p<0.01) higher than that of plain kefir samples. While adding orange to plain kefir samples reduced the amount of ethanol, adding grapefruit increased its amount, conversely. Plain kefir samples had higher acetic acid, butanoic acid, hexanoic acid, octanoic acid, n-decanoic acid, benzoic acid, benzaldehyde, benzaldehyde (2,5 bis), silanediol dimethyl, and benzyl alcohol ratios than that of orange, mandarin and grapefruit samples. However, the dlimonene, 1-methyl benzene and benzene 2-ethyl-1,3-dimethyl ratios of kefir samples containing orange, mandarin and grapefruit increased significantly compared to plain kefir. Panelists preferred orange (23 % and 37.5 %) and mandarin (37.5 %) kefir samples more than the others. Panelists gave lower scores to grapefruit-added samples than the other kefir samples. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the behavior of Listeria monocytogenes during the manufacture and storage of artisanal kefir. A five-strain cocktail of L. monocytogenes was introduced (at ca. 3.0 log10 CFU/mL) into UHT milk as a pre-fermentation contaminant. The growth of L. monocytogenes, lactic acid bacteria and yeasts was monitored during the 24-h fermentation period of milk with two types of kefir grains at 20 °C and the subsequent storage of kefir under adequate (4 °C) and inadequate (10 °C) refrigerated-storage conditions. L. monocytogenes grew into much higher cell densities (5.3–5.8 log10 CFU/mL) by the end of the fermentation period, but the final (24-h) counts were substantially lower than those obtained in the corresponding control trials with unfermented milk (7.2 log10 CFU/mL). The growth rate of L. monocytogenes during fermentation differed depending on the type of kefir grain used. During the subsequent 11-day storage of the kefir filtrates at 4 °C or 10 °C, the behavior of L. monocytogenes varied from no growth to further population increases (of up to 1.1 log10 CFU/mL), depending on the storage temperature, but also depending on the type of kefir grain and the grain surface-to-weight ratio that had been used to ferment the milk. This study highlights the need for strict adherence to good hygiene practices during artisanal kefir making and shows that L. monocytogenes can sustain considerable growth during milk fermentation and further grow during the subsequent cold storage of kefir, particularly under inadequate refrigerated storage conditions. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Pathogenic bacteria are usually present in raw milk. In order to prevent pathogens from growing, milk should be fermented. The present research work aimed to isolate lactic acid bacteria (LAB) from kefir, a fermented milk beverage, and assess their antibacterial activity against chosen pathogenic strains of bacteria. MATERIALS AND METHODS: An experimental investigation was carried out in the laboratory. Samples of kefir were collected from a local organic food store in Jeddah City, Saudi Arabia. LAB isolates were identified phenotypically and biochemically. The agar well diffusion technique evaluated the antimicrobial activities (AMAs) of LAB isolates against Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium. The isolates were molecularly identified through polymerase chain reaction PCR amplification of the 16S rRNA gene. RESULTS: Six LAB isolates were identified and given the following numbers: SK9, SK17, SK23, SK24, SK28, and SK33. The isolates belong to Enterococcus durans and Leuconostoc mesenteroides. After screening for antibacterial activity against food-borne bacteria, SK28 showed the strongest AMA against E. coli and S. Typhimurium. SK23 showed the highest AMA against L. monocytogenes, while SK33 showed no AMA against L. monocytogenes. CONCLUSIONS: LAB isolates exhibited AMA against the selected strains of bacteria. Enterococcus isolates showed the highest antibacterial activities against the tested bacterial strains. Therefore, in the era of antimicrobial resistance, they might serve as antibiotic alternatives. L. monocytogenes was the least sensitive to the antimicrobial activities of LAB isolates. Further experiments are required to isolate and identify the molecules responsible for the antimicrobial activities. [ABSTRACT FROM AUTHOR]

ABSTRACTMicroorganisms are ubiquitous in nature and are central to human, animal, environmental, and planetary health. They play a particularly important role in the food chain and the production of high-quality, safe, and health-promoting foods, especially fermented foods. This important role is not always apparent to members of the public. Here, we describe Kefir4All, a citizen science project designed to provide the general public with an opportunity to expand their awareness, knowledge, and practical skills relating to microbiology, introduced through the medium of producing fermented food, i.e., milk kefir or water kefir. During the course of Kefir4All, 123 citizen scientists, from second-level school and non-school settings, participated in a study to track changes in the microbial composition of kefirs, by performing and recording details of milk kefir or water kefir fermentations they performed in their homes or schools over the 21-week project. At the start of the study, the citizen scientists were provided with milk or water kefir grains to initiate the fermentations. Both types of kefir grain are semi-solid, gelatinous-like substances, composed of exopolysaccharides and proteins, containing a symbiotic community of bacteria and yeast. The experimental component of the project was complemented by a number of education and outreach events, including career talks and a site visit to our research center (Kefir Day). At the end of the study, a report was provided to each citizen scientist, in which individualized results of their fermenting activities were detailed. A number of approaches were taken to obtain feedback and other insights from the citizen scientists. Evaluations took place before and after the Kefir4All project to gauge the citizen scientist’s self-reported awareness, knowledge, and interest in microbiology and fermented foods. Further insights into the level of citizen science participation were gained through assessing the number of samples returned for analysis and the level of participation of the citizen scientists throughout the project. Notably, the survey results revealed a self-reported, increased interest in, and general knowledge of, science among the Kefir4All citizen scientists after undertaking the project and a willingness to take part in further citizen science projects. Ultimately, Kefir4All represents an example of the successful integration of citizen science into existing education and research systems.

Context: Water kefir is a fermented beverage that is typically made in the home by inoculating a sugar-rich solution with a microbial community (water kefir grains). Several studies on the metabolite content and hepatoprotective effects of water kefir have been published, but carbon tetrachloride (CCl4)-induced acute liver injury has not been studied. Aims: To evaluate the efficacy of water kefir in vivo against hepatoprotective CCl4-induced acute liver injury and to in silico investigate metabolites that play an important role in hepatoprotective mechanisms. Methods: The present study aimed to investigate the hepatoprotective activity of water kefir in an animal model caused by CCl4. Furthermore, using molecular docking, the metabolites found in water kefir were evaluated for their role in the NF-κB and Nrf2 signaling pathways. Results: Water kefir significantly and dose-dependently alleviated acute liver injury caused by CCl4. Water kefir administration at all doses produced results comparable to the positive control (Curcuma extract). Molecular docking simulations showed that, compared to Nrf2, the 25 metabolites were more likely to interact with the NF-kB receptor. Fumaric acid is the strong metabolite that interacts with the NF-κB receptor with a free energy of binding and an inhibition constant of -6.66 kcal/mol and 13.22 µM, respectively. Conclusions: Water kefir administration improved the condition of liver damage, characterized by a decrease in serum levels of AST, ALT, TNF-a, TGF-b, and an improvement in the liver tissue profile. In silico evaluation showed that the metabolites in water kefir were able to interact with target proteins in the NF-kB and Nrf2 pathways. It was concluded that water kefir improves the condition of the liver by reducing the level of necrosis and fibrosis.

This study aimed to improve the functional quality of goat-milk kefir by adding secang wood extract. The initial stage of the research was the extraction of secang wood using distilled water. Kefir is made by mixing secang wood extract and pasteurized goat milk with 5% kefir grains, then incubated at 25̊C for 20 hours. Goat-milk kefir was then tested for physicochemical quality (i.e., total solids, water content, pH value, acidity value, viscosity, and alcohol content), microbiological quality (i.e., total lactic acid bacteria (LAB) and total yeast), organoleptic properties, antimicrobial activity against Escherichia coli and Staphylococcus aureus, and antioxidant activity. The results showed that the physicochemical quality of kefir with the addition of secang wood extract had an effect (p

This is the first study that investigates the effect of kefir with an emphasis on the production of short-chain fatty acids (SCFAs) during the fermentation process in food products. The products developed and characterized were an artisanal cream cheese without cream and one with added cream, and for the analysis of the fatty acid profile, both cream cheeses were compared with commercial cream cheese. The artisanal cream cheese had a high amount of lactic acid bacteria characterizing the product formed by Lactobacilli and a low concentration of lactose due to the fermentation process. Compared to commercial cream cheese, our products without and with added cream had a higher concentration of short-chain fatty acids (SCFAs), especially butyric acid, which is important for the health of the gastrointestinal tract, omega 3, and oleic fatty acid, which has been associated with the prevention and control of some diseases. Overall, the artisanal cream cheese cream with fermented cream with kefir grains is a functional product with an innovative character compared to current products on the market and was well accepted by the younger public. This new product comes as an option for those who need to change their eating habits and maintain a healthy lifestyle.

Coccidiosis and necrotic enteritis (NE) are prevalent poultry ailments worldwide, leading to decreased live performance and elevated mortality rates without antibiotic usage. This study evaluated Nigella sativa (black cumin) seeds (BCS) and kefir as alternatives to antibiotics for broilers. An in vivo study over a 28-day period, using 384 Cobb 500 male broilers organized into six treatment groups as part of a completely randomized block experimental design was conducted. Each treatment group included eight replicates, with each replicate containing eight birds. The treatments included positive control, negative control, antibiotic control, 5% BCS in feed, 20% kefir in drinking water, and a combination of 5% BCS and 20% kefir. NE was induced in broilers by administering ~5000 oocysts of Eimeria maxima orally on day 14, followed by inoculation with about 108 CFU/mL of Clostridium perfringens (Cp) (strain Cp#4) on days 19, 20, and 21. Live performance metrics including feed intake, body weight gain, and feed conversion were assessed in broilers. Additionally, NE disease outcomes such as lesion scores, mortality rates, and Cp populations in cecum were determined during the study. The BCS, kefir, and the combination had no detrimental effect on broiler live performance. BCS-treated and combination groups had lower NE scores (p > 0.05) in comparison to the positive control and exhibited no significant difference (p > 0.05) from antibiotic control. Additionally, treatment groups and antibiotic control were not significantly different (p > 0.05) in mortality, whereas the BCS and kefir combination significantly reduced (p < 0.05) mortality to 14.1% compared to 31.3% for the positive control. C. perfringens vegetative cells significantly decreased (p < 0.05) in treatments with BCS, kefir, and their combination on days 22 and 28 compared to the positive control. On day 22, Cp sores were significantly lower (p < 0.05) for the kefir and combination treatments compared to the positive control. In conclusion, BCS and kefir successfully reduced C. perfringens infection and mortality without any detrimental impact on broiler live performance with the combined treatment being the most effective. These results suggest that BCS and kefir could serve as potential alternatives to antibiotics in managing NE.

New licuri-based kefir beverages were obtained using water kefir grains as fermentation inoculum (1, 2.5, and 5%) under different fermentation times (24 and 48 h). Metagenomic sequencing of the kefir grains adapted to the aqueous licuri extract revealed Lactobacillus hilgardii and Brettanomyces bruxellensis to be predominant in this inoculum. The excellent adaptation of the kefir grains to the licuri extract raised the possibility of prebiotic action of these almonds. The beverages showed acidity values between 0.33 ± 0.00 and 0.88 ± 0.00 mg lactic acid/100 mL and pH between 3.52 ± 0.01 and 4.29 ± 0.04. The viability of lactic acid bacteria in the fermented beverages was equal to or greater than 108 CFU/mL, while yeasts were between 104 and 105 CFU/mL. There were significant differences (p < 0.05) in the proximate composition of the formulations, especially in the protein (1.37 ± 0.33–2.16 ± 0.84) and carbohydrate (5.86 ± 0.19–11.51 ± 1.26) contents. In addition, all the samples showed good stability in terms of acidity, pH, and viability for LAB and yeasts during 28 days of storage (4 °C). Overall, the beverages showed a dominant yellow-green color, non-Newtonian pseudoplastic behavior, and high mean scores in the sensory evaluation. This study provided evidence of the emerging potential of licuri in the plant-based beverage industry.

Kefir is a fermented product obtained from goat, sheep and cow milk as a result of lactic acid and ethyl alcohol fermentation. In this study, it was aimed to investigate the possibility of producing an alternative functional kefir product from almond milk. It was enriched with banana and honey to improve its sensory properties. Samples were stored at +4oC for 14 days. The pH and dry matter of samples containing almond milk were lower than those containing cow’s milk. Serum separation increased with the increase of almond milk ratio. The use of banana increased dry matter and viscosity, and decreased serum separation. pH, dry matter and viscosity decreased during storage. The highest L* value was observed in the control kefir produced from 100% cow’s milk, and the lowest in the samples containing honey and banana on the 1st day of storage. It can be said that the addition of honey increases the b* value and the addition of banana decreases the b* value. As almond milk ratio and storage time increased, bacteria counts decreased. The lactococci counts of the samples with banana added (except for the control) were higher than the others. In the samples with banana and honey, a higher increase in yeast count was observed during storage compared to plain kefir (control sample). It can be said that the use of almond milk reduces the general acceptability of kefir. Almond milk can be successfully used in kefir production as a substitute for cow’s milk, if sweeteners, fruit and thickeners are used.

Abstract Background Depression is prevalent among individuals with non-alcoholic fatty liver disease (NAFLD) and can cause poor health outcomes. Moreover, a solid bilateral association between NAFLD and depression has been shown, which may alleviate by kefir consumption. Thus, we aimed to investigate the effect of milk kefir drinks on the depression status of individuals with NAFLD. Methods In a secondary outcome analysis of a randomized, single-blinded, controlled clinical trial, 80 adults with grades 1 to 3 of NAFLD were included in an 8-week intervention. Participants were randomly assigned to Diet or Diet + kefir groups to either follow a low-calorie diet or a low-calorie diet along with a 500 cc milk kefir drink daily. The participants’ demographic, anthropometric, dietary, and physical data were recorded before and after the study. Depression status was assessed using the Persian format of the second version of the Beck Depression Inventory (BDI-II-Persian) at the baseline and after 8 weeks of intervention. Results Overall, 80 participants aged 42.87 ± 10.67 years were included in the analysis. The data on the baseline demographic, dietary, and physical activity of the groups were not significantly different. During the study, participants in Diet + Kefir group had a significantly decreased energy (P = 0.02), carbohydrate (P = 0.4), and fat consumption (P = 0.4). However, during the study, the depression score was not significantly reduced in the Diet group, the Diet + Kefir group showed a significant reduction in depression (P = 0.02). However, between-group analyses for changes in depression were not significant (P = 0.59). Conclusion Consumption of milk kefir drink for 8 weeks may not reduce depression symptoms in adults with NAFLD. Trial registration The trial was registered at IRCT.ir as IRCT20170916036204N6 (August 2018).