Microflora structure and functional capacity in Tibetan kefir grains and selenium-enriched Tibetan kefir grains: A metagenomic analysis.

Tibetan kefir grains (TKGs) are a complex protein-lipid-polysaccharide matrix composed of various microorganisms. Microorganisms have the benefit of being effective, secure, and controllable when used for selenium enrichment. In this study, selenium-enriched Tibetan kefir grains (Se-TKGs) were made, and the microbiology composition was analyzed through a metagenomic analysis, to explore the influence of selenium enrichment. The microbial composition of TKGs and Se-TKGs, as well as the probiotic species, quorum sensing system (QS) and functional genes were compared and evaluated. Lactobacillus kefiranofaciens was the most abundant microbial species in both communities. Compared with TKGs, Se-TKGs had a much higher relative abundance of acetic acid bacteria. Lactobacillus helveticus was the most common probiotic species both in TKGs and Se-TKGs. Probiotics with antibacterial and anti-inflammatory properties were more abundant in Se-TKGs. QS analysis revealed that Se-TKGs contained more QS system-associated genes than TKGs. Moreover, Kyoto Encyclopedia of Genes and Genomes analysis revealed that the pathway for human disease ko01501 had the greatest relative abundance in both TKGs and Se-TKGs. Compared with TKGs, Se-TKGs demonstrated a greater relative abundance of different drug resistance-related metabolic pathways. Additionally, linear discriminant analysis effect size was used to examine the biomarkers responsible for the difference between the two groups. In this study, we focused on the microbiological structure of TKGs and Se-TKGs, with the aim of establishing a foundation for a more thorough investigation of Se-TKGs and providing a basis for exploring potential future use.

Effects of fermented dairy products on inflammatory biomarkers: A meta-analysis.

AIM: Fermented dairy products (FDPs) are made from raw milk under the action of specific microorganisms by lactic acid bacteria fermentation or co-fermentation of lactic acid bacteria, bifidobacteria, and yeast. The aim of this study was to explore the effects of FDPs on inflammatory biomarkers. DATA SYNTHESIS: A comprehensive search was conducted on four electronic databases, including PubMed, Web of Science, Embase, and the Cochrane Library. Finally, fourteen trials (15 arms) were included in this meta-analysis: yogurt (n = 9), fermented milk (n = 4), and kefir (n = 2). Additionally, the random effects model or fixed-effects model was used to pool the study results. Firstly, the analysis indicated that FDPs' supplementation decreased the levels of C-reactive protein (CRP) (SMD = -0.21; 95% CI: -0.40, -0.02; P = 0.033) and increased interferon-gamma (IFN-γ) levels (SMD = 0.12; 95% CI: 0.01, 0.23; P = 0.033). Furthermore, we obtained some statistically significant results in the following subgroups: CRP decreased in participants with metabolic diseases. IFN-γ increased in the intervention that lasted ≥12 weeks, Asian, yogurt, and healthy population. Finally, there was no significant effect on tumor necrosis factor-alpha, interleukin (IL)-6, IL-10, and IL-2. CONCLUSIONS: FDPs reduced CRP and increased IFN-γ, but they had no effect on other inflammatory markers. The results showed that the consumption of FDPs was slightly associated with reduced inflammation, but because of the limited literature, these results should be interpreted with caution.

Screening of lactic acid bacteria strains with urate-lowering effect from fermented dairy products.

Hyperuricemia is a well-known cause of gout and also a risk factor for various comorbidities. Current agents like xanthine oxidase inhibitors prevent hyperuricemia, but usually induce severe side effects. Alternative strategies, such as novel dietary supplementations, are necessary for the management of hyperuricemia. Lactic acid bacteria (LAB) have been used in human diet for a long time with a good safety record. In this study, 345 LAB strains isolated from traditional fermented dairy products were tested for assimilating abilities of guanosine. Two LAB strains, Lacticaseibacillus rhamnosus 1155 (LR1155) and Limosilactobacillus fermentum 2644 (LF2644), showing great capacities of guanosine transformation and degradation were selected. Compared to LR1155, LF2644 showed a better effect with 100.00% transforming rate and 55.10% degrading rate. In an in vivo test, a hyperuricemic rat model was established and the results showed that administration of LR1155 (p < 0.01) or LF2644 (p < 0.01) prevented the rise of serum uric acid with more than 20% decrease when compared with the hyperuricemia rats. In addition, an increased fecal uric acid level was observed in LF2644 or LR1155 treated rats (LR1155-M p < 0.05, others p < 0.01). This study proved that LR1155 and LF2644 can be promising candidates of dietary supplements for prevention or improvement of hyperuricemia. PRACTICAL APPLICATION: The LAB strains tested in this study could be considered as good potential probiotic candidates for dietary supplements because of their urate-lowering effects, which provide a novel antihyperuricemic strategy with advantages of safety and sustainability.

Evaluation of probiotics in vegetable juices: tomato (Solanum lycopersicum), carrot (Daucus carota subsp. sativus) and beetroot juice (Beta vulgaris).

Probiotics are known to human kind since ages as they are important component in fermented milk products, however the use of probiotics in non-dairy product is a novel method for the delivery of probiotics. Delivery of probiotics through non-dairy products will be beneficial for consumers who are lactose intolerant who are deprived of benefits of probiotics by dairy products. This studies aim at developing novel vegetable juices containing probiotic bacteria. Three different strains of bacteria have been used, i.e. Lactobacillus plantarum, Lactobacillus acidophilus, Lactobacillus delbrueckii in carrot, beetroot and tomato juice. The viability of the bacteria has been checked after a specific duration of time of fermentation by Koch's plate count method. The vegetable used for juices (carrot, beetroot, tomato) consist of high amount of antioxidants like carotenoids in carrot, betaxanthins and betacyanins in beetroot, lycopene in tomato. These antioxidant provide numerous health benefits to human body. The antioxidant activity in the juices has been checked before and after fermentation by HPLC and spectroscopic methods. The three bacterial strains Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus delbrueckii used in three types of juices including tomato juice, carrot juice and beetroot juice showed good growth except Lactobacillus acidophilus due to reasons like insufficient nutrients. The amount of sugars and acids of the three juices indicated that the fermentation process takes place at a good and satisfying rate. This product will be especially useful for the people who are lactose intolerant who cannot intake probiotics via milk and milk products. Vegetable juices also have almost zero fat content and high in fiber so the people who are on a fat free diet can consume this product.

Effects of varying casein and pectin concentrations on the rheology of high-protein cultured milk beverages stored at ambient temperature.

Shelf-stable cultured milk beverages that have high protein levels can be difficult to successfully manufacture. With increasing protein level, rapid phase separation and gel formation occur in cultured beverages, which may not be prevented even with the inclusion of stabilizers such as high methoxy (HM) pectin. To limit protein aggregation in cultured milk beverages we investigated micellar casein as an interesting alternative to milk, due to the absence of whey proteins, which can contribute to increased gel strength in cultured products. In this study, micellar casein dispersed in ultrafiltered milk permeate was fermented to pH 4.1, blended with HM pectin, homogenized, thermally processed, and bottled for storage at ambient temperature for 6 mo. Utilizing response surface methodology with a central composite rotatable design, the protein and pectin contents were varied between 5 and 9% and 0.0 and 1.0%, respectively. The elastic modulus, loss tangent, and yield stress of these beverages were measured during storage to observe the extent of bond restructuring, whereas particle size and visual phase separation were measured to determine stability. Response variables were measured initially after thermally processing the beverages, and after 1 and 6 mo of storage at ambient temperature. All samples quickly formed gels after homogenizing, regardless of the pectin level. The stiffness (elastic modulus) of all samples increased throughout storage and was determined mainly by the protein content; however, the growth of elastic bonds over time was slowed with high levels of pectin. At 6 mo of storage, yield stress values were significantly lower for beverages with <7.5% protein when they were stabilized with ≥0.85% pectin. Prediction models for visual phase separation in beverages stored for 6 mo were significantly affected by the protein content, with increasing instability at lower protein levels. Models were used to identify optimal protein (<7.5%) and pectin (≥0.85%) concentrations to minimize the stiffness of gels during ambient storage. Samples in this optimized region were predicted to have low yield stress values and were easily fluidized by gentle shaking of the bottle at 6 mo.

Fermented egg-milk beverage alleviates dextran sulfate sodium-induced colitis in mice through the modulation of intestinal flora and short-chain fatty acids.

Fermented egg-milk beverage (FEMB) can alleviate the symptoms of intestinal diseases by regulating intestinal flora and supplying nutrition. This study investigated the protective effect of FEMB on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. The results showed that FEMB relieved the UC mice's pathological abnormalities and colonic inflammation, and restructured the intestinal flora composition simultaneously. After FEMB treatment for 14 days, the body weight of the mice rose and the disease activity index (DAI) value decreased. Furthermore, the length and form of colons in the UC mice were notably restored. Inflammatory cells decreased or disappeared, and goblet cells and crypt were enriched and modified. 16S rRNA gene sequencing results demonstrated that FEMB treatment could increase the abundance of beneficial bacteria in the cecum content of mice, including unclassified_f_Lachnospiraceae and Lactobacillus. Moreover, probiotics that can increase the content of short-chain fatty acids (SCFAs) may contribute to inflammation alleviation. An increase in amino acids was observed in our experiment, which may benefit nutritional supplements. In conclusion, FEMB treatment can alleviate the damage of DSS-induced colitis in Balb/c mice. This study provides a theoretical basis for both the relief of inflammation and the application of FEMB.

Evaluating the technological properties of lactic acid bacteria in Wagyu cattle milk.

This paper reveals the technological properties of lactic acid bacteria isolated from raw milk (colostrum and mature milk) of Wagyu cattle raised in Okayama Prefecture, Japan. Isolates were identified based on their physiological and biochemical characteristics as well as 16S rDNA sequence analysis. Streptococcus lutetiensis and Lactobacillus plantarum showed high acid and diacetyl-acetoin production in milk after 24 h of incubation at 40 and 30°C, respectively. These strains are thought to have potential for use as starter cultures and adjunct cultures for fermented dairy products.

Direct evidence of the preventive effect of milk replacer-based probiotic feeding in calves against severe diarrhea.

Diarrhea is a major cause of death in calves and this is linked directly to economic loss in the cattle industry. Fermented milk replacer (FMR) has been used widely in clinical settings for calf feeding to improve its health and growth. However, the protective efficacy of FMR on calf diarrhea remains unclear. In this study, we verified the preventive effects of FMR feeding on calf diarrhea using an experimental infection model of bovine rotavirus (BRV) in newborn calves and a field study in dairy farms with calf diarrhea. In addition, we evaluated the protective efficacy of lactic acid bacteria-supplemented milk replacer (LAB-MR) in an experimental infection model. In the experimental infection, calves fed FMR or high-concentrated LAB-MR had diarrhea, but the water content of feces was lower and more stable than that of calves fed normal milk replacer. The amount of milk intake also decreased temporarily, but recovered immediately in the FMR- and LAB-MR-fed calves. As compared with the control calves, FMR- or LAB-MR-fed calves showed less severe or reduced histopathological lesions of enteritis in the intestinal mucosa. In a field study using dairy calves, FMR feeding significantly reduced the incidence of enteritis, mortality from enteritis, duration of a series of treatment for enteritis, number of consultations, and cost of medical care for the disease. These results suggest that feeding milk replacer-based probiotics to calves reduces the severity of diarrhea and tissue damage to the intestinal tract caused by BRV infection and provides significant clinical benefits to the prevention and treatment of calf diarrhea.

Bioactive peptides from food fermentation: A comprehensive review of their sources, bioactivities, applications, and future development.

Bioactive peptides (BPs) are specific protein fragments that exert various beneficial effects on human bodies and ultimately influence health, depending on their structural properties and amino acid composition and sequences. By offering promising solutions to solve diverse health issues, the production, characterization, and applications of food-derived BPs have drawn great interest in the current literature and are of particular interest to the food and pharmaceutical industries. The microbial fermentation of protein from various sources is indubitably a novel way to produce BPs with numerous beneficial health effects. Apart from its lower cost as compared to enzymes, the BPs produced from microbial fermentation can be purified without further hydrolysis. Despite these features, current literature shows dearth of information on the BPs produced from food via microbial fermentation. Hence, there is a strong necessity to explore the BPs obtained from food fermentation for the development of commercial nutraceuticals and functional foods. As such, this review focuses on the production of BPs from different food sources, including the extensively studied milk and milk products, with emphasis on microbial fermentation. The structure-activity (antihypertensive, antioxidant, antimicrobial, opiate-like, anti-inflammatory, anticancer/antiproliferative, antithrombotic, hypolipidemic, hypocholesterolemic, and mineral binding) relationship, potential applications, future development, and challenges of BPs obtained from food fermentation are also discussed.

Biotransformation of Major Ginsenoside Rb1 to Rd by Dekkera anomala YAE-1 from Mongolian Fermented Milk (Airag).

Dekkera anomala YAE-1 strain separated from "airag" (Mongolian fermented mare's milk) produces ß-glucosidase, which can convert ginsenoside Rb1 from Panax ginseng. Ginseng-derived bioactive components such as ginsenoside Rb1 have various immunological and anticancer activities. Airag was collected from five different mare milk farms located near Ulaanbaatar, Mongolia. YAE-1 strains were isolated from airag to examine the hydrolytic activities of ß-glucosidase on Korean Panax ginseng using an API ZYM kit. Supernatants of selected cultures having ß-glucosidase activity were examined for hydrolysis of the major ginsenoside Rb1 at 40°C, pH 5.0. The YAE-1 strain was found to be nearly identical at 99.9% homology with Dekkera anomala DB-7B, and was thus named Dekkera anomala YAE-1. This strain exerted higher ß-glucosidase activity than other enzymes. Reaction mixtures from Dekkera anomala YAE-1 showed great capacity for converting ginsenoside Rb1 to ginsenoside Rd. The ß-glucosidase produced by Dekkera anomala YAE-1 was able to hydrolyze ginsenoside Rb1 and convert it to Rd during fermentation of the ginseng. The amount of ginsenoside Rd was highly increased from 0 to 1.404 mg/ml in fermented 20% ginseng root at 7 days.

Cancer-protective effect of a synbiotic combination between Lactobacillus gasseri 505 and a Cudrania tricuspidata leaf extract on colitis-associated colorectal cancer.

Previously, a synbiotic combination of probiotic Lactobacillus gasseri 505 (LG) and a new prebiotic, Cudrania tricuspidata leaf extract (CT) in fermented milk, designated FCT, showed an in vitro immunomodulatory effect and antioxidant activity. Although synbiotic combination might have cancer-protective effects, these activities have not been fully validated in vivo. Ten-week treatment of LG, CT, or FCT to azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colitis-associated colorectal cancer (CAC) mouse model reduced both the incidence of colonic tumors and damage to the colonic mucosa effectively, suggesting a cancer-protective effect. To understand these, biomarkers associated with inflammation, colon barrier, apoptosis, and cancer cell proliferation were monitored in AOM/DSS group versus LG/CT/FCT groups. A synbiotic combination (FCT) down-regulated pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1ß, and IL-6) and inflammation-associated enzymes (iNOS and COX-2), and up-regulated anti-inflammatory cytokines (IL-4 and IL-10). In addition, colon barrier experiment revealed that biomarkers of mucus layer (MUC-2 and TFF3) and tight junction (occludin and ZO-1) were up-regulated. Subsequent apoptosis experiment showed that pro-apoptotic factors (p53, p21, and Bax) were up-regulated and anti-apoptotic factors (Bcl-2 and Bcl-xL) were down-regulated. Furthermore, comparative metagenome analysis of gut microbiota revealed that Staphylococcus decreased but Lactobacillus, Bifidobacterium, and Akkermansia increased, supporting their protective effects, accompanied by increased short-chain fatty acids (SCFAs). Taken together, the FCT administration showed cancer-protective effects by reducing the risk of colitis-associated colon cancer via regulation of inflammation, carcinogenesis, and compositional change of gut microbiota. Consequently, the synbiotic combination (FCT) could be a novel potential health-protective natural agent against CAC.

The effect of aeration and mixing in developing a dairy-based functional food rich in menaquinone-7.

Vitamin menaquinone-7 (MK-7) supplementation improves bone health and reduces the incidence of osteoporosis. Despite the recent developments in MK-7 fermentation using Bacillus subtilis natto, low fermentation yields, as well as complicated downstream processing steps, are still the main reasons for the expensive final product. To overcome these issues, developing a fermented dairy-based product rich in MK-7 by avoiding costly downstream steps and optimising the fermentation operating conditions to enhance the MK-7 concentration would be an alternative approach. The present study, therefore, aims to evaluate the role of agitation and aeration as the key operating conditions on MK-7 production by Bacillus subtilis natto using a milk media. The agitation and aeration rates of 525 RPM and 5 VVM were found to be the optimum levels leading to the production of 3.54 mg/L of MK-7. Further, the sensory evaluation was performed to compare the sensory properties of the freeze-dried fermented samples with non-fermented milk samples. The results illustrated that the fermented samples had a significant saltiness with intense aroma resulting in the less acceptability of them by the panellists.

Are Probiotics the New Calcium and Vitamin D for Bone Health?

PURPOSE OF REVIEW: Calcium and vitamin D supplementation is recommended for patients at high risk of fracture and/or for those receiving pharmacological osteoporosis treatments. Probiotics are micro-organisms conferring a health benefit on the host when administered in adequate amounts, likely by influencing gut microbiota (GM) composition and/or function. GM has been shown to influence various determinants of bone health. RECENT FINDINGS: In animal models, probiotics prevent bone loss associated with estrogen deficiency, diabetes, or glucocorticoid treatments, by modulating both bone resorption by osteoclasts and bone formation by osteoblast. In humans, they interfere with 25-hydroxyvitamin D levels, and calcium intake and absorption, and slightly decrease bone loss in elderly postmenopausal women, in a quite similar magnitude as observed with calcium ± vitamin D supplements. A dietary source of probiotics is fermented dairy products which can improve calcium balance, prevent secondary hyperparathyroidism, and attenuate age-related increase of bone resorption and bone loss. Additional studies are required to determine whether probiotics or any other interventions targeting GM and its metabolites may be adjuvant treatment to calcium and vitamin D or anti-osteoporotic drugs in the general management of patients with bone fragility.

Preliminary study for the stimulation effect of plant-based meals on pure culture Lactobacillus plantarum growth and acidification in milk fermentation.

Fermented dairy products have been recognized as the best carriers for the administration of probiotics. Because one of the potential probiotic strains, Lactobacillus plantarum, has poor proteolytic ability and weak acidifying capacity in milk fermentation, the aim of this study was to preliminarily investigate the stimulation effect of plant-based meals on L. plantarum CCFM8661 growth in milk, and subsequently develop a yogurt or yogurt drinks containing probiotic strain L. plantarum CCFM8661. Milk supplemented with different concentrations (5 to 10%, wt/wt) of oat extract and malt extract, inoculated with 2.5 × 107 cfu/mL of L. plantarum CCFM8661, and then incubated at 35°C. The pH value, titration acidity, and viable cell counts during 48-h fermentation at 35°C and 25-d storage at 4°C, were determined at different intervals. The results showed that the promotion effects of oat extract and malt extract on L. plantarum CCFM8661 growth rate in milk were much stronger than almond, walnut, sweet corn, peanut, and soybean meals. In addition, the stimulation effect of oat extract was associated with its concentration, and was much stronger than that of malt extract. Furthermore, viable counts and titration acidity of yogurt were gradually increased in the oat extract group, whereas viable counts were gradually decreased and titration acidity were slightly increased in the malt extract group during the 25-d storage at 4°C.

A synbiotic combination of Lactobacillus gasseri 505 and Cudrania tricuspidata leaf extract prevents hepatic toxicity induced by colorectal cancer in mice.

Colorectal cancer (CRC) is known to be a life-threatening disease and commonly leads to metastasis in the liver. Fermented milk acts as an effective carrier for probiotic strains, whose consumption improves host health. Our previous study indicated that fermented milk that included a synbiotic combination of Lactobacillus gasseri 505 (505) and Cudrania tricuspidata leaf extract (CT) resulted in significantly greater anti-oxidative effects than fermented milk without CT. Therefore, we hypothesized that fermented milk containing CT and 505 (FCT) could result in hepatoprotective effects against CRC-induced liver metastasis. Liver inflammation and CRC were induced in male C57BL/6J mice, using azoxymethane/dextran sodium sulfate, and 505, CT, and FCT were administered to the 3 sample-treated 505, CT, and FCT groups, respectively, for 10 wk. The results showed that FCT treatment significantly reduced serum aspartate aminotransferase and alanine aminotransferase concentrations and elevated albumin concentrations. Moreover, the results of histological analysis showed that hepatic steatosis was notably reduced in the FCT group. Among the 3 sample-treated groups, the expression of mRNA associated with enzymes showing anti-oxidative activities, such as superoxide dismutase, catalase, and glutathione reductase, was the highest in the FCT-treated mice. In addition, FCT administration resulted in the greatest anti-inflammatory activity, as inflammatory marker levels (i.e., tumor necrosis factor-α, cyclooxygenase-2, myeloperoxidase, and nuclear factor kappa-light-chain enhancer of activated B cells) were significantly downregulated at the mRNA level and the expression of proteins associated with the nuclear factor kappa-light-chain enhancer of activated B cells and mitogen-activated protein kinase signaling pathways was suppressed by FCT. Therefore, this study demonstrated that fermented milk containing novel synbiotics has the potential to prevent hepatic toxicity induced because of CRC owing to its enhanced anti-oxidative and anti-inflammatory activities.

Beneficial effect of GABA-rich fermented milk on insomnia involving regulation of gut microbiota.

Insomnia is a common health problem in modern societies. GABA, an inhibitory neurotransmitter, can promote relaxation and reduce anxiety. In this study, milk was fermented with Lactobacillus brevis DL1-11, a strain with high GABA-producing capacity. The potential beneficial effects of this fermented milk on anxiety and sleep quality were evaluated in animal experiments. Sixty mice were divided into control, non-GABA fermented milk (NGFM), low-dose GABA fermented milk (LGFM, 8.83 mg/kg.bw), medium-dose GABA fermented milk (MGFM, 16.67 mg/kg.bw), high-dose GABA fermented milk (HGFM, 33.33 mg/kg.bw) and diazepam groups. The results of open field test and elevated plus-maze test indicated decreases in anxiety behavior after oral HGFM administration. Moreover, mice in the HGFM group exhibited a significantly prolonged sleep time after an intraperitoneal injection of sodium pentobarbital and a shortened sleep latency after an intraperitoneal injection of sodium barbital. These results indicate a beneficial effect of HGFM on sleep. Additionally, significant increases in the relative abundances of Ruminococcus, Adlercreutzia and Allobaculum and the levels of some short-chain fatty acids (SCFAs), such as butyric acid, were observed in the HGFM group. The results suggest that GABA-fermented milk may improve sleep and the protective pathways may involve in regulation of gut microbiota and increase of SCFAs level.

Desenvolvimento de produto gorduroso a base de fermentado anaeróbico de leite colostral ovino / Development of fat product based on anaerobic fermentate of sheep colostral milk

O uso de colostro é uma opção para o desenvolvimento de produtos alimentícios alternativos, já que seu uso para produção de lácteos convencionais é prejudicada por conta de sua alta instabilidade aos tratamentos térmicos tradicionais. Além de seu uso na alimentação de neonatos, o colostro pode ser amplamente utilizado na alimentação humana, desde que adequadamente tratado. O objetivo deste estudo foi avaliar o uso deste leite após fermentação aeróbica para produzir concentrado gorduroso semelhante à manteiga. Colostro de ovelhas Lacaune foi submetido à fermentação anaeróbica em garrafas de polietileno tereftalato (PET) por 30 dias em temperatura ambiente (± 15ºC). Após este período, a porção líquida foi drenada e a porção sólida foi batida até a inversão da fase gordurosa e sua transformação em manteiga. O leite, a porção sólida e a manteiga produzida foram avaliadas quanto a sua caracterização físicoquímica. O leite apresentou 8,75% de gordura, 7,12% de proteína, 3,90% de lactose e 21,11% de extrato seco total...

The use of colostrum is an option for the development of alternative milk products as its high instability to conventional heat treatments precludes its use for regular dairy production. Other than its common use in the feeding of newborns, colostrums can be widely used for human consumption, provided its proper treatment. The objective of this study was to evaluate the technological capacity of colostrums after anaerobic fermentation, in order to turn it into a butter-like fat concentrate. Colostrum from Lacaune ewes was subjected to anaerobic fermentation in polyethylene terephthalate (PET) bottles at room temperature (± 15ºC) for 30 days. The liquid portion was removed, and the solid fraction was beaten until the inversion of the fat portion into butter. The colostrum, the solid fraction, and the final butter-like product were analyzed for their physicochemical characteristics. The colostrum presented 8.75% fat, 7.12% protein, 3.90% lactose, and 21.11% total dry extract

Use of Streptococcus thermophilus for the in situ production of γ-aminobutyric acid-enriched fermented milk.

γ-Aminobutyric acid (GABA) is a potentially bioactive ingredient with health-promoting properties that is added to functional foods. Streptococcus thermophilus was selected to produce naturally GABA-enriched fermented milk. This strain can yield a GABA concentration of 2.8 g/L after a 48-h fermentation. In the presence of 1 g/L food-grade casein hydrolysate as a nitrogen source, S. thermophilus yielded GABA concentrations as high as 5.4 g/L or even 8.3 g/L when cocultured with Lactobacillus rhamnosus. In other words, both of these added conditions promoted GABA enrichment. The GABA dose achieved with fermented milk was comparable to the doses of commercially available GABA supplements. Additionally, the in situ use of S. thermophilus to produce GABA-enriched fermented milk was cost effective. The complete genomic sequence of S. thermophilus GABA has been published and will be highly useful to other researchers studying the regulation of genes related to GABA accumulation. In conclusion, the S. thermophilus GABA-producing strain reported herein represents a natural method for the production of fermented milk containing high GABA concentrations.

Recovery of Lactobacillus casei strain Shirota (LcS) from faeces with 14 days of fermented milk supplementation in healthy Australian adults.

BACKGROUND AND OBJECTIVES: A key measure for classifying bacteria as a probiotic is the ability to survive gastric transport and be recoverable in faeces. The aim of this study was to determine whether Lactobacillus casei strain Shirota (LcS) could be recovered in the faeces of healthy young Australian adults following ingestion of a fermented milk drink. METHODS AND STUDY DESIGN: A cohort of 25 healthy individuals (male/female: 14/11; age: 29.3±6.6 years; BMI: 25.3±2.7 kg/m2, mean±SD) ingested one 65 ml bottle of fermented milk containing 6.5×109 LcS live cells daily for 14 days. Participants provided a faecal sample at day 0, day 7 (mid-supplementation), day 14 (end of supplementation) and 14 days after cessation of the supplement (day 28) for assessment of the number of viable LcS via microbial culture on selective media with confirmation using a colony-direct polymerase chain reaction and species-specific primers. RESULTS: The supplement was well tolerated by participants. No LcS colonies were recovered from participants prior to ingestion of the fermented milk drink. All participants had recoverable LcS colonies at day 7 and day 14, with a mean recovery of 6.5±1.1 and 6.4±1.1 log10 CFU/g of faeces (mean±SD) at each time point respectively. LcS was detectable in only one sample at 14 days following the cessation of supplementation. CONCLUSIONS: Live LcS is recoverable in faeces from healthy Australian adults following daily ingestion of a fermented milk drink.

Impact of Buckwheat Fermented Milk Combined with High-Fat Diet on Rats' Gut Microbiota and Short-Chain Fatty Acids.

The aim of this study was to evaluate the effect of buckwheat fermented milk on intestinal flora and short-chain fatty acids (SCFAs) of rats fed a high-fat diet (HFD). Buckwheat fermented milk was made with Lactobacillus plantarum ST-Ⅲ, Lactobacillus bulgaricus, and Streptococcus thermophilus. Thirty-six males C57BL/6 rats (aged 3 weeks and with 9 to 12 g weight) were subjected to a 2-week adaptive period on a normal diet. After a week of acclimatization, the rats were randomly divided into three groups with 12 rats in each group. The high-fat diet with fermented milk (HFDFM) group received HFD supplemented with fermented milk, and the high-fat diet supplemented with buckwheat fermented milk (HFDBFM) group received HFD plus buckwheat fermented milk. Besides, the gavage dose was 0.4 mL/day. After the feedings, colon levels of cytokines and antioxidant indices of the liver, colon, and duodenum tissues were measured. The composition of intestinal flora of rats and the content of SCFAs were determined by gas chromatography-mass spectrometry and Illumina high-throughput sequencing technology. Supplementation with buckwheat fermented milk significantly inhibited the increases in lipopolysaccharide levels in colon and antioxidant indexes in the HFD-fed rats. In addition, buckwheat fermented milk could significantly enhance Firmicutes and decrease Bacteroidetes compared to HFDFM. In addition, SCFA concentrations in HFDBFM were higher than other groups. In conclusion, buckwheat fermented milk can alleviate the damage of HFD to intestinal flora of rats. It modulates microbiota composition and SCFA concentrations to balance the intestinal environment, which will benefit to rats' intestinal health. PRACTICAL APPLICATION: This study explored the effect of buckwheat fermented milk on the regulation of intestinal microflora and SCFAs in rats fed a high-fat diet. It provides new ideas for the development of buckwheat fermented food.