Streptococcus thermophilus

This research aimed to optimize the growth of commercial yogurt starter cultures (Streptococcus thermophilus and Lactobacillus bulgaricus) on coconut milk before they were applied in the production of coconut yogurt, which is known as niyogurt or cocogurt. The research consists of three steps. Firstly, both microbes were grown on 100% cow’s milk and were analyzed for pH and total lactic acid bacteria (LAB) to examine the length of fermentation time. Secondly, both microbes were gradually grown on cow’s milk and coconut milk media, with samples ranging in combinations of the two kinds of milk from 100% milk to 100% coconut milk. Finally, the optimized starter cultures were then applied to niyogurt production. The results showed that the pH of the starter cultures obtained in 100% milk after 48 hours of fermentation was 4.41±0.04 for Streptococcus thermophilus and 4.44±0.03 for Lactobacillus bulgaricus. Meanwhile, the total lactic acid bacteria counts were 8.62±3.03 log cfu/ml for Str...

To analysis and compare the drug resistance of lactic acid bacteria isolated from yoghurt made in China and outside of China. Yoghourt products were purchased from Nanchang supermarkets. The Lactic acid bacteria bacterias in yoghourt were isolated by MRS, MC and M17 medium. The isolated strains were identified by gram’s stain, colony morphology observation and biochemistry reaction test. Drug resistance analysis of the identified strains were analyzed by K-B method. 26 kinds of Lactic acid bacteria, 13 strains of cocci and 13 strains of bacillus, were isolated. All strains were identified by physiology and biochemistry test. They were Lactic acid bacteria bulgaricus, Lactic acid bacteria delbrueckii subsp. Bulgaricus, Streptococcus thermophilus. Bifidobacteria (Bacillus bifidus). Drug resistance analysis revealed that the 26 strains of Lactic acid bacteria showed multiple drug resistance to 13 kinds of antibiotics, such as kanamycin. And all of these Lactic acid bacteria were comple...

Streptococcus thermophilus cultures were grown either on trehalose or lactose, immobilized in alginate beads, dipped in various protective solutions and dried by either convection air-drying (CAD) or freeze-drying (FD). Immobilized cultures dipped in the 0.1% peptone solution did not show good survival to CAD or FD, as mortality was over 99%. There was no significant difference in mortality levels, in both methods of drying, when lactose or trehalose were used as protective ingredients. The highest survival levels (50 to 98%) were with a whey-sucrose protective medium, but this was potentially related to a higher pH and solids of the solution. Mortality levels were higher in FD than CAD, and this did not appear to be related to the fact that FD cultures had lower residual moisture contents than those dried under CAD. Cells grown on lactose had slightly higher survival rates to drying than those obtained from CAD. Trehalose-positive and trehalosenegative cultures of S. thermophilus did not show different mortality patterns to CAD or FD. Lactic acid bacteria (LAB) are commonly used in the production of cheese, yoghurt, dry sausages, wine, sourdough breads and sauerkraut. In many processes, a commercial culture is added directly to the food matrix, or in culture media for the production of starters. The commercial cultures available to the processors are marketed mostly in two forms: frozen and dried. The process used for the drying of food-related LAB is freezedrying (FD), which is an expensive and slow method of drying. Bakers' yeast, on the other hand, are dried by fluid-bed technology, and the application of

A popular dairy product, yogurt is well-known for its high probiotic content and health advantages. Enhancing its nutritional profile with fruits has gained significant attention due to the increasing consumer demand for functional and health-promoting foods. Fruits serve as natural sources of vitamins, minerals, dietary fiber, antioxidants, and bioactive compounds that can enhance the overall nutritional quality of yogurt. This review explores the impact of fruit fortification on the physicochemical, sensory, and probiotic properties of yogurt. It discusses the selection of fruits and their influence on yogurt flavor and sensory properties. Additionally, the potential health benefits, including improved antioxidant activity, gut health, and immune support, are highlighted. The findings suggest that fruit-enriched yogurt offers a promising strategy for developing functional dairy products with enhanced nutritional and sensory attributes.

Fermented dairy products not only have a long shelf-life but also have beneficial nutritional values. The products are deficient in dietary fiber and certain bioactive compounds. Adding grains to dairy products is a widespread practice to improve the nutritional and economic aspects. In this work, we studied the effect of fermented millet–milk beverages (FMBs) using pearl millet grains and three different dairy by-products (sweet whey, sweet buttermilk, and skimmed milk). A control treatment prepared with water was also manufactured for comparison. Samples were continuously prepared and fermented using a commercial yogurt starter culture (YC-381) containing L. delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and a pure strain of L. paracasei subsp. Paracasei. Four FMBs (water based: WB-FMB, whey based: WHB-FMB, buttermilk based: BMB-FMB, and skimmed milk based: SMB-FMB) were analyzed during cold storage at 4 °C for up to 15 days for chemical, microbiological properties, mi...

We optimized the conditions for generating random amplified polymorphic DNA (RAPD) profiles of Streptococcus thermophilus strains by using the polymerase chain reaction (PCR). Several factors can cause the amplification of false and non reproducible bands in the RAPD profiles. We tested three primers, OPI-02 MOD, M13 and XD9 throughout this study. In addition, we tested different concentrations of primer, DNA template and Taq DNA polymerase. We adjusted the ratio of the primer to DNA template. All the three primers yielded reproducible profiles on several days, under optimized concentrations of components and cycling parameters used. The bands of such profiles probably corresponded to perfect annealing sites amplified with good efficacy or present in multiple copies in the genome. Five months later, repeated experiment generated identical bands. However, extra faint bands were detected with M13 and XD9 primers, possibly, corresponding to nonspecific binding resulting from slight var...

Lactic acid bacteria (LAB) are widely used for the industrial production of fermented dairy products and form a group of related low-GC-content gram-positive bacteria. The major species used in dairy manufacturing are Lactobacillus, Lactococcus, Streptococcus, and Leuconostoc. Traditionally most are applied as starter cultures for dairy fermentations or used as probiotic cultures, delivered in dairy vehicles. The appearance of the genomes of Lactococcus lactis, Bidifobacterium longum, Lactobacillus plantarum, L. johnsonii, L. acidophilus, 2 strains of Streptococcus thermophilus, and pending completion of many draft genomic sequences, is now promoting in-depth investigation into the comparative genetic content of LAB. Moreover, whole-genome transcriptional arrays are quickly revealing critical genes/operons that are coordinately expressed and the impact of environmental factors on expression of multiple gene sets. Comparative genomics between multiple genomes is providing insights into genes that are important in metabolic, physiological, and functional roles for different LAB in the environments they inhabit, ranging from the gastrointestinal tract to milk and acidified dairy products. J. Nutr. 137: 748S-750S, 2007.

Thirty-five different lactic acid bacteria (LAB) strains were screened for their conjugated linoleic acid (CLA) isomers (C18:2 cis-9, trans-11 and C18:2 trans-10, cis-12) producing ability from linoleic acid (LA) in sheep’s milk. Preliminary experiments revealed that Lactobacillus delbrüeckii ssp. bulgaricus 2230 and Streptococcus thermophilus St 360 among the screened strains had the highest CLA-producing ability. This two strains were assayed in an 11-run fractional factorial design to investigate the effect of four variables included glucose, powdered sheep milk, LA and inoculum ratio on CLA production in a sheep’s milk yogurt. The optimum conditions for producing the highest levels of CLA (42.86%) were obtained by adding 10.00 mg/mL of glucose, 30.00 mg/mL of powdered sheep milk, 0.90 mg/mL of LA and a 1:2 (St:Lb) ratio of bacterial strains in the inoculum. This CLA-rich sheep’s milk yogurt could be an important supplementary food source for increasing the CLA in the human diet. 

The aim of this work was to design a novel mixed probiotic culture for piglets and to evaluate its beneficial effect on the piglets' gut health. The possible mechanisms of probiotic activity, such as adhesion, competitive pathogen exclusion and influence on gut microbiota diversity were determined. Mixed probiotic starter culture is composed of three thermophilic lactic acid bacteria (LAB) strains: Lactobacillus helveticus BGRA43, Lactobacillus fermentum BGHI14 and Streptococcus thermophilus BGVLJ1-44. The strains BGVLJ1-44 and BGRA43 showed good technological properties (fast milk curdling, strong proteolytic activity). In addition, the strain BGVLJ1-44 produces exopolysaccharide (EPS), BGHI14 is heterofermentative LAB strain with significant immunomodulatory effect, while the strain BGRA43 showed strong antimicrobial activity against different pathogens and exhibited significantly higher level of adhesion to Caco-2 cells comparing to other two strains. Both lactobacilli strain...

A great number of factors can influence milk fermentation for yoghurt production such as fermentation conditions, starter cultures and milk characteristics. It is important for dairy companies to know the best combinations of these parameters for a controlled fermentation and for the desired qualities of yoghurt. This study investigates the use of a 1H-NMR metabolomics approach to monitor the changes in milk during fermentation from time 0 to 24 h, taking samples every hour in the first 8 h and then at the end-point at 24 h. Three different starter cultures (L. delbrueckii ssp. bulgaricus, S. thermophilus and their combination) were used and two different heat treatments (99 or 105 °C) were applied to milk. The results clearly show the breakdown of proteins and lactose as well as the concomitant increase in acetate, lactate and citrate during fermentation. Formate is found at different initial concentrations depending on the heat treatment of the milk and its different time trajecto...

The yield and chemical structures of exopolysaccharides (EPS) produced by many strains of Streptococcus thermophilus have been characterized. However, the kinetics (or production profile) for EPS during milk fermentation is not clear. In this study, we investigated whether any differences existed in the yield and molar mass of EPS when milk was fermented at the same acidification rate by 2 strains of S. thermophilus (St-143 and ST-10255y). The type of EPS produced by these 2 strains is different. Milk samples were analyzed for EPS concentration every 30 min during a fermentation period of 270 min (final pH 4.5) by using a modified quantification method, which was faster and validated for its recovery of added EPS. Rheological properties of milks during fermentation were also analyzed using small-strain dynamic oscillatory rheology. For the determination of molar mass, EPS extracts were isolated by ultrafiltration of whey obtained during fermentation of milk to pH values 5.2, 4.9, 4.7, and 4.5, and molar mass was analyzed using size-exclusion chromatographymulti-angle laser light scattering. During fermentation, both strains appeared to start producing significant amounts of EPS after about ~150 min, which corresponded to pH ~5.3, which was close to the point of gelation. During the remainder of the fermentation process (150-270 min), the EPS concentration from strains St-143 and ST-10255y significantly increased from 30 to 72 mg/L and from 26 to 56 mg/L, respectively. The quantity of EPS recovered by our modified method was estimated to represent ~60% of the total EPS added to milk. The molar mass of EPS produced by both strains appeared to slightly decrease during fermentation. At pH 5.2, EPS from St-143 and ST-10255y had molar masses of 2.9 × 10 6 and 1.4 × 10 6 g/mol, respectively, which decreased to 1.6 × 10 6 and 0.8 × 10 6 g/mol, respectively, when the pH of milk was 4.5. Distinct differences were apparent in the rheological properties of gels fermented by the 2 strains. At the end of fermentation, St-143 fermented milk had weaker gels with storage modulus (G′) value at pH 4.6 of 26 Pa, whereas gels made with ST-10255y were stiffer with a G′ value at pH 4.6 of 82 Pa. For St-143 gels, maximum loss tangent (LT max ) values were higher (0.50) and occurred earlier (at a higher pH value) than the LT max values (0.46) for gels from ST-10255y strain. Because the fermentation conditions were identical for both strains, the observed changes in rheological properties could be due to the differences in chemical structures and molar mass of the EPS produced by these 2 S. thermophilus strains.

BackgroundProbiotic supplements, by definition, provide a benefit to the host, but few studies have investigated the effect of probiotic supplements in healthy adult populations.PurposeThe present, single arm, open label clinical trial, evaluated compositional and functional changes in the fecal microbiome of healthy adults after supplementation with a 14-strain probiotic.MethodsWe analysed the effect of a 14-strain probiotic blend (Bacillus subtilis NCIMB 30223, Bifidobacterium bifidum NCIMB 30179, B. breve NCIMB 30180, B. infantis NCIMB 30181, B. longum NCIMB 30182, Lactobacillus helveticus NCIMB 30184, L. delbrueckii subsp. bulgaricus NCIMB 30186, Lacticaseibacillus paracasei NCIMB 30185, Lactiplantibacillus plantarum NCIMB 30187, Lacticaseibacillus rhamnosus NCIMB 30188, L. helveticus NCIMB 30224, Lactobacillus salivarius NCIMB 30225, Lactococcus lactis subsp. lactis NCIMB 30222, and Streptococcus thermophilus NCIMB 30189), on the faecal microbiota of healthy young adults (n=41)...

The improvement of milk dairy products’ quality and nutritional value during shelf-life storage is the ultimate goal of many studies worldwide. Therefore, in the present study, prospective beneficial effects of adding two different industrial yeasts, Kluyveromyces lactis and Saccharomyces cerevisiae pretreated by heating at 85 °C for 10 min to be inactivated, before fermentation on some properties of ABT fermented milk were evaluated. The results of this study showed that the addition of 3% and 5% (w/v) heat-treated yeasts to the milk enhanced the growth of starter culture, Lactobacillus acidophilus, Bifidobacteria, and Streptococcus thermophilus, during the fermentation period as well as its viability after 20 days of cold storage at 5 ± 1 °C. Furthermore, levels of lactic and acetic acids were significantly increased from 120.45 ± 0.65 and 457.80 ± 0.70 µg/mL in the control without heat-treated yeast to 145.67 ± 0.77 and 488.32 ± 0.33 µg/mL with 5% supplementation of Sacch. cerevi...

This study aimed to evaluate the impact of adding Egyptian grape seed (Red Romi) extract (GSE) to traditional Labneh in order to enhance its shelf life and functionality availability. Labneh was divided into four treatments; the first one served as control (with no GSE), the second, third and fourth treatments contained 0.05, 0.1 and 0.2% of GSE, respectively. During cold storage period, levels of titratable acidity increased, while levels of moisture decreased in all treatments. Addition of GSE resulted in an increase of the antimicrobial and antioxidant activities of crude extract of Labneh. Also, Labneh samples fortified with GSE had more shelf life than control. GSE did not negatively effect on the viability of starter culture. Labneh fortified with 0.2% GSE showed the lowest score for its appearance

This study was carried out to evaluate the protective effect of two different types of Karish cheese, differing in starter culture used, against development of non-alcoholic fatty liver disease (NAFLD) in rat model. For that purpose, Wister rats were randomized into three groups; rats in the control group were fed high fructose (70%) diet while rats in experimental groups were fed the same diet mixed with 10 % of Karish cheese containing Streptococcus thermophilus NRRL-B- 41401 (group II) or Karish cheese containing Lactobacillus acidophilus NRRL-B-4495 and Bifidobacterium longum NRRL-B- 41409 with the same strain of Streptococcus thermophilus (group III). After five weeks of intervention, levels of plasma triglycerides, cholesterol, glucose, liver biomarkers (ALT and AST), interleukin (IL)-6, fecal enterobacteriaceae and hepatic index were significantly ( p < 0.05) increased in rats in control group as compared to rats in both experimental groups. Also, levels of plasma liver ma...

AflatoxinM1 (AFM1) has been the major mycotoxin frequently found in milk and dairy products. These products are widely consumed by infants and children who are more susceptible to adverse effects of mycotoxins, considering its significant impact on human health. Determination of AFM1 levels in dairy products becomes imperative, so the present study was undertaken to investigate the levels of AFM1 in some milk products consumed widely by infants and children and marketed in Sharkia Governorate markets. For this purpose total of 80 milk product samples were randomly collected. Aflatoxin M1 was detected in 23 (28.75%) out of the 80 samples analyzed in which the levels of AFM1 of the samples were found to exceed the limits (0 ng/kg) allowed by Egyptian regulation. Results of yoghurt examination showed that 3 (12%) of the local processed type contain AFM1 and exceeding Egyptian permissible limits, with a mean value 0.803 ± 0.1322 ng/kg, while processed cheese results also exceeded Egyptian permissible limits in 11 (44%) of examined samples and ranged from 23.2 to 47.1 ng/kg. Of the analyzed Infant formula milk powder samples, 2 (13.3%) samples were contaminated by AFM1. 7 (46.67%) of the UHT milk samples exceeded the permissible limit where the highest recorded level was 33.4 ng/kg. The results of this study indicate that continuous monitoring of AFM1 levels in commonly marketed milk products in Sharkia markets should be regularly done.

The Rheology of yogurt was influenced by the dry matter of milk and yogurt cultures. The purpose of this research was to determine the effect of using single culture (L. bulgaricus, S. thermophillus) and mixed culture (L. bulgaricus and S. thermophillus), (S. thermophillus, L. bulgaricus and Bifidobacterium)as much as 3% for evaluation of physicochemical properties in set yoghurt such as pH value, acidity content, viscosity and syneresis, also to know total exopolysaccharides (EPS) production, total lactic acid bacteria (LAB) and microstructure of set yoghurt storage at refrigerator temperature (1 day, 2 and 3 days). The method of this research on first step was Randomized Completely Design, the variables measured on first step were pH content, acidity content, viscocity, and syneresis with 3 times replication. On second step used Randomized Completely Nested Design (3x4) with 3 times replication variables measured were pH stored, total lactic acid bacteria and total EPS production. The best treatment from second step continued testing of the microstucture with the aim of identifying structure components in set yoghurt. The conclusion on first step this research could decrease of pH value, increase the acidity, viscosity and inhibit syneresis set yogurt. On second step gave has decline in the average total LAB 1 log (CFU / ml) in set yogurt and has increasing of total exopolysaccharide production from each type of culture during.

The effect of incubation time by using three culture starters (Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophiles) and Taro (Colocasia Esculenta) starch as a stabilizer on the physicochemical and microbial characteristics of yoghurt were investigated. One of the problems in making yoghurt is the occurrence of syneresis caused by the unstable casein micelles. The addition of natural stabilizers is known to be able to solve the problem. In this research, local taro was added to the yoghurt as stabilizers followed by different incubation time (18-h, 24-h, 30-h, 36-h and 42-h). The results showed that incubation time had a highly significant effect (p<0.01) on viscosity, whey holding capacity (WHC), moisture content, carbohydrates, pH value, total acidity, and total lactic acid bacteria. During the fermentation process, the prolonged incubation time resulted in increased acidity, viscosity, WHC, and total lactic acid bacteria, while simultaneously decr...

A large amount of whey is being produced in India every day during preparation of chhana and chhana based sweetmeats. The drainage of the whey produced not only increases the BOD load of the environment but also causes loss of essential nutrients. Preparation of chhana whey based fermented beverage is one of the key processes of effective utilization of whey. In the present study two chhana whey based beverages were prepared separately by fermenting the whey with two different cultures namely Streptococcus thermophilus NCDC-74 (Beverage I) and Yoghurt culture YC-470 containing Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus (Beverage II) by adding at 2% inoculum level. The average total solid, fat, protein and lactose content were found to be 22.30, 0.18, 0.259, 4.39% and 22.79, 0.20, 0.26, 4.31% in beverage I and beverage II respectively. The overall sensory score of both the beverages were significantly higher (P less than 0.05) than that of control sample...

A great number of factors can influence milk fermentation for yoghurt production such as fermentation conditions, starter cultures and milk characteristics. It is important for dairy companies to know the best combinations of these parameters for a controlled fermentation and for the desired qualities of yoghurt. This study investigates the use of a 1H-NMR metabolomics approach to monitor the changes in milk during fermentation from time 0 to 24 h, taking samples every hour in the first 8 h and then at the end-point at 24 h. Three different starter cultures (L. delbrueckii ssp. bulgaricus, S. thermophilus and their combination) were used and two different heat treatments (99 or 105 °C) were applied to milk. The results clearly show the breakdown of proteins and lactose as well as the concomitant increase in acetate, lactate and citrate during fermentation. Formate is found at different initial concentrations depending on the heat treatment of the milk and its different time trajecto...

Streptococcus thermophilus is a thermophilic lactic acid bacterium used as starter culture for the manufacture of fermented dairy products. For the production of Crescenza and other soft cheeses, Sacco has developed and provides dairies with three different defined blends of S. thermophilus strains. Each blend contains two different S. thermophilus strains. The strains were selected based on their unique technological properties as well as different phage profiles. Analysis of 133 whey samples collected in 2009-2010 from Italian dairies showed a high prevalence (about 50%) of bacteriophage attacks on the blend ST020. More specifically, the strain S. thermophilus ST1A was found to be the preferred target of the bacteriophages. A bacteriophage insensitive mutant (BIM5) of the phage-sensitive strain ST1A was successfully developed and used to substitute strain ST1A in the Crescenza starter culture ST020. The strain BIM5 showed identical technological and industrial traits as those of the phage-sensitive strain ST1A. The improved resistance of the modified Crescenza starter culture ST020R was confirmed at Italian dairies, and its effectiveness monitored on 122 whey samples collected in 2011-2012. Compared to the previous values (2009)(2010), the use of the phage-hardened blend ST020R allowed reducing of frequency of phage attacks from about 50 to less than 5% of the whey samples investigated.

Background: Reducing the sugar content of processed products has been claimed to be one of the most efficient strategies for decreasing sugar intake. To investigate what level of sugar reduction is accepted in set-type yogurt, we conducted a hedonic test focusing on the sensory attributes and assessed the nutritional quality of the yogurt. Methods: We prepared a total of 12 set-type yogurt samples using four sugar concentrations (viz. 0, 4, 5 and 12%). The starter culture was used as a 1:1 ratio mixture of Streptococcus thermophilus and Lactobacillus bulgaricus. The sensorial, chemical and microbiological analyses were performed. Result: From the investigation, yogurt containing at least 4 and 5% added sugar was found acceptable based on overall sensory score. On the hedonic scale, yogurt containing 12% sugar was more often described as too sweet compared with yogurt containing 4 and/or 5% sugar. On the other hand, the sweetness and aroma intensity for yogurt containing 0% sugar was...

ABSTRACTImmunostimulatory sequences of oligodeoxynucleotides (ODNs), such as CpG ODNs, are potent stimulators of innate immunity. Here, we identified a strong immunostimulatory CpG ODN, which we named MsST, from the lac Z gene of Streptococcus (S.) thermophilus ATCC19258, and we evaluated its immune functions. In in vitro studies, MsST had a similar ability as the murine prototype CpG ODN 1555 to induce inflammatory cytokine production and cell proliferation. In mouse splenocytes, MsST increased the number of CD80+CD11c+and CD86+CD11c+ dendritic cells and CD4+CD25+ regulatory T cells. We also analyzed the effects of MsST on the expression of regulatory cytokines by real‐time quantitative PCR. MsST was more potent at inducing interleukin‐10 expression than the ODN control 1612, indicating that MsST can augment the regulatory T cell response via Toll‐like receptor 9, which plays an important role in suppressing T helper type 2 responses. These results suggest that S. thermophilus, who...

Four strains of lactic acid bacteria as the following I-Str. thermophilus + Lactobacillus acidophilus + B. befidium (1:2:1) treatment (B). II-Str. thermophilus + Lactobacillus helveticus + B. befidium (1:1:2) treatment (C). Str. thermophilus + Lactobacillus bulgaricus + B. befidium (1:2:2) treatment (D) were evaluated to their abilities at viability and growth rate when grown with Bifidobacterium befidium to produce bioyoghurt as compared to traditional yoghurt made by traditional yoghurt starter IV-Str. thermophilus + Lactobacillus bulgaricus (1 : 1) treatment (A). Resultant yoghurt chemically, rhiologically, microbiologically and sensory evaluated when it was fresh or during storage period. Results showed that pH values in all treatments were higher than those in control and the acidity was in inverse trend to the pH in all treatments and control. T.V.F.A. values were increased in all treatments and control with the progress in storage periods as well as, treatment (B) gained the highest T.V.F.A. value among other treatments and control. Curd syneresis was in a correlation with the progress of acid content. Also, total bacterial count was increased with progress in storage until 3 days followed by a decrease but treatment (D) gained the highest growth rate among other treatments and control yoghurt. The strains were enhanced when they grown in a combination with Bifidobacterium befidium all except Lactobacillus acidophilus. No growths on macconkey agar media, no molds and yeast in all treatments and control yoghurt in fresh or stored product. The presence of proteolytic and lipolytic bacteria was increased with the progress in storage periods. Sensory evaluation data showed the consumers acceptance of all treatments except treatment (B) where it was weak in body and texture and more flat in aroma. From these results we can concluded that bio-yoghurt with healthy properties can be made with a combination with Bifidobacterium befidium to enhance its viabilities and to achieve the probiotic dose number (10 6 cfu/gm) without any aroma, body and texture defects. Also, these results orientate the future research works to enhance the properties of bio-yoghurt contains Streptococcus thermophilus, Lactobacillus acidophilus and Bifidobacterium befidium as starter culture.

In view of the growing demand for alternatives to animal products, this study presents the development and physicochemical, microbiological and sensory characterization of a yogurt-type product based on lupine milk (Lupinus mutabilis) and starch from arracacha (Arracacia xanthorrhiza). Three versions of the product were formulated with different concentrations of starch, evaluating its proximal composition, polyphenol content, rheological behavior, microbiological profile and sensory acceptance. The results showed that the incorporation of starch did not significantly affect the basic nutritional composition, maintaining an adequate protein and fiber profile. The formulation with 3 % starch (T3) presented higher viscosity, rheological stability and sensory acceptability analysis, standing out in attributes such as flavor, texture and appearance. In addition, the pseudoplastic behavior observed suggests a favorable texture for the consumer. At the microbiological level, all formulations met safety standards, showing an adequate presence of lactic acid bacteria with probiotic potential. Therefore, this work not only highlights the potential of lupin as a base for functional fermented products but also highlights the importance of arracacha starch as a natural stabilizer. The findings open new perspectives for the development of innovative, sustainable and nutritionally balanced plant-based foods, with projection towards the food industry and the growing market of vegan and food intolerant consumers.

The main purpose of this research is to provide information about the effect of Bifidobacterium longum ATCC15707 on the characteristics of yogurt during different of storage period. The B.longum was obtained from Laboratory of Food and Nutrition Collection Culture Gadjah Mada University and a S.thermophillus + L.bulgaricus (1:1) was obtained from a commercial yogurt (Milkuat). This research was performed in Laboratory of Animal Science and Dairy Milk Processing Industry, Gadjah Mada University, used 8 L fresh milk cow, yogurt sample were stored at 4 oC for 28 days.  Research using Completely Randomized Design with Factorial pattern A x B (4 x 2). Factor A is the ration between yogurt starter ST+Lb and BL (T1 is control 4% from yogurt starter, T2 1:3 (v/v), T3 2:2 (v/v), T4 3:1(v/v)). Factor B is the storage period (1 and 21 days) for chemical, physical and organoleptic analyses and (1, 14, 21 and 28) for microbial. Parameters measured are microbiology (total lactic acid bacteria), c...

Aiming at the most optimal starter cultures to be selected, a research was conducted to evaluate the effect of 5 different combinations of starter cultures on the dynamics of lactic acid fermentation during the production of white brine cow cheese. The raw milk used for the cheese production demonstrated certain deviations of the chemico-physical and microbiological properties most probably resulting from mastitis. The progressive acidity development was in the first 20 days of cheese ripening for all variants and after 60 days it ranged from 92.8 -104.7 0 SH. After the two-month aging period, the moisture percentage was 48.8 -53.4%, the percentage of ripeness varying from 40 to 55 0 Š. In order to produce 1 kg of cheese, 6.57 -6.94 l of milk were used, or 14.41 -15.22 kilograms of cheese were produced from 100 l of milk. The best sensory evaluation results were achieved with the variant using a combination of several starter cultures being as follows: DVS mesophilic culture (Str. lactis i Lb. casei -2:1), FRC 75 (Lac. lactis subsp. lactis, Lac. lactis subsp. cremoris, Str. thermophilus and Lactobacillus delbruecki, subspecies bulgaricus) and developed thermophilic culture (Str. thermophilus and Lactobacillus delbruecki, subspecies bulgaricus -2:1).

The main purpose of this research is to provide information about the effect of Bifidobacterium longum ATCC15707 on the characteristics of yogurt during different of storage period. The B.longum was obtained from Laboratory of Food and Nutrition Collection Culture Gadjah Mada University and a S.thermophillus + L.bulgaricus (1:1) was obtained from a commercial yogurt (Milkuat). This research was performed in Laboratory of Animal Science and Dairy Milk Processing Industry, Gadjah Mada University, used 8 L fresh milk cow, yogurt sample were stored at 4 ºC for 28 days. Research using Completely Randomized Design with Factorial pattern A x B (4 x 2). Factor A is the ration between yogurt starter ST+Lb and BL (T1 is control 4% from yogurt starter, T2 1:3 (v/v), T3 2:2 (v/v), T4 3:1(v/v)). Factor B is the storage period (1 and 21 days) for chemical, physical and organoleptic analyses and (1, 14, 21 and 28) for microbial. Parameters measured are microbiology (total lactic acid bacteria), chemistry (acidity, pH, total solids, fat, protein and lactose), physical (viscosity) and organoleptic quality (color, texture, taste, performance, sweetness, acidity, bitterness and rancidity). If there is a real effect of treatment was followed by Duncan Multiple Test and LSD test for organoleptic quality. Microbial counts were log transformed and statistically evaluated. The result indicated that the yogurt produce with 3% (S.thermophillus and L. delbrueckii subsp. bulgaricus) and 1% B.longum ATCC15707 during storage period (1 and 21 days) at 4 ºC effected significantly to increase acidity and total solid of yogurt more than other treatment, decrease pH value significantly different. Also this ratio between starter bacteria obtained the high score in the taste and texture from the panelists.

We studied the roles of Streptococcus thermophilus phosphogalactosyltransferase (EpsE) (the priming enzyme), tyrosine kinase (EpsD), phosphatase (EpsB), and a membrane-associated protein with no known biochemical function (EpsC) in exopolysaccharide (EPS) synthesis. These proteins are well-conserved among bacteria and are usually encoded by clustered genes. Exopolysaccharide synthesis took place in the wild-type strain and a mutant lacking EpsB but not in mutants lacking EpsC, EpsD, or EpsE. The three mutants unable to synthesize EPS lacked the EpsE phosphogalactosyltransferase activity, while the two EPS-synthesizing strains possessed this activity, showing that EpsC and EpsD are required for EpsE function. An EpsD phosphorylated form was found in all strains except the epsC mutant, indicating that EpsC is necessary for EpsD phosphorylation. Moreover, the phosphorylated form of EpsD, a supposedly cytoplasmic protein, was found to be associated with the plasma membrane, possibly due to interaction with EpsC. Finally, the EpsD and EpsE elution profiles in a gel filtration chromatography assay were similar, suggesting that these two proteins colocalize in the membrane. Mutation of Tyr200, predicted to be a phosphorylation site and present in a conserved motif in bacterial phosphoglycosyltransferases, led to EpsE inactivation. In contrast, mutation of Tyr162 or Tyr199 had no effect. Taken together, these data show that EpsD controls EpsE activity. Possible mechanisms for this control are discussed.

Streptococcus thermophilus isolates from traditional butter 'Smen', a fermented product from cow's and ewe's milk in arid area was subjected to taxonomical investigations. The identification procedure included phenotypic approaches, molecular characterization by using genus polymerase chain reaction (PCR) amplifications for sodA gene encoding the manganese-dependant superoxide dismutase A, and species-specific primers from gene encoding glucose kinase (glcK), gene encoding DNA polymerase III (dnaE) and gene encoding threonyl-tRNA synthetase (thrS) housekeeping genes in order to distinguish among reference, and wild strains of S. thermophilus and for their differentiation from Enterococcus spp. A total of 12 strains were tested by DNA identification analysis and these indigenous isolates were unambiguously characterised by their housekeeping gene profiles. Finally, four genotypes were recognised. To our knowledge, this is the first report on the isolation and molecular characterization of S. thermophilus strains from fermented milk transformed into home-production butter provided from Southern West Algeria. These results are of particular interest as they favour the selection of future cultures starters as S. thermophilus from traditional dairy products. It is, therefore, of great importance to preserve the genetic pool of the wild strains.

Streptococcus thermophilus isolates from traditional butter 'Smen', a fermented product from cow's and ewe's milk in arid area was subjected to taxonomical investigations. The identification procedure included phenotypic approaches, molecular characterization by using genus polymerase chain reaction (PCR) amplifications for sodA gene encoding the manganese-dependant superoxide dismutase A, and species-specific primers from gene encoding glucose kinase (glcK), gene encoding DNA polymerase III (dnaE) and gene encoding threonyl-tRNA synthetase (thrS) housekeeping genes in order to distinguish among reference, and wild strains of S. thermophilus and for their differentiation from Enterococcus spp. A total of 12 strains were tested by DNA identification analysis and these indigenous isolates were unambiguously characterised by their housekeeping gene profiles. Finally, four genotypes were recognised. To our knowledge, this is the first report on the isolation and molecular characterization of S. thermophilus strains from fermented milk transformed into home-production butter provided from Southern West Algeria. These results are of particular interest as they favour the selection of future cultures starters as S. thermophilus from traditional dairy products. It is, therefore, of great importance to preserve the genetic pool of the wild strains.

In the present study, a dried whey crystalline lactose f WCL) preparation IMS obtained from deproteinized whey by crystallization in an ethanol-water system. This was used as a major component in Streptococcus WCL ( S W C L ) broth and in Modijied MI7 ( M M I 7 ) agar media. S W C L broth and MMI 7 "gar were used as media for propagating and counting several strains of lactococci and Streptococcus thermophilus, respectively. The study as carried out to compare the alternative utilization o j S W C L broth to RSM (reconstituted skim milk) and M M I 7 q a r to original MI 7 agar. The streptococcal cultures tested in this study remained viable through several transfers in S W C L broth medium. However, high acidity development was not observed in S W C L broth cultures. The presence of 4 g/l yeast extract in S W C L broth had more effect on growth than on acid production. Growth in S W C L broth or RSM was dependent upon the type of streptococcal culture used. M M I 7 agar gave comparable results to M I 7 agur in terms of counts of the lactococci and Strep thermophilus propagated in S WCL broth or in RSM.

In this study, it was aimed to determine microbial flora members in three traditional Tulum cheeses (C1, C2 and C3) produced in different villages and settlement areas in I ˙zmir, Turkey. For this purpose, culture depended and 16S rRNA based culture independent methods were used. According to the results of culture depended method, Lactococcus spp., Enterococcus spp., Staphylococcus spp., Lactobacillus spp., Pediococcus spp. and yeast-mold were detected in all samples at different levels. In order to determine and identify both of the culturable and nonculturable microorganisms, denaturing gradient gel electrophoresis (DGGE) method was used. DGGE results have shown that there were eight different dominant microorganisms (Streptococcus thermophilus, Lactococcus lactis subs. lactis, Streptococcus infantarius subs. infantarius, Lactobacillus gallinarum, Streptococcus equinus, Enterococcus faecalis, Enterococcus faecium, Lactococcus garvieae) in three regionally cheese samples. Further more, total bacterial loads were monitored with real-time PCR (qPCR) method. According to the results, 3.5 9 10 8 , 3.8 9 10 8 , 8.4 9 10 8 copy number of DNA was detected in C1, C2 and C3 cheese samples, respectively. This study is the first description for the dynamics of microbial composition of Izmir Tulum cheese after the production and brining processes.

Probiotics are functional foods and are becoming more evident with time that probiotics can have prophylactic and therapeutic roles. Current report revealed that an established probiotic cocktail of Lactobacillus delbruckei sp. bulgaricus DWT1 and Streptococcus thermophilus DWT4, could inhibit tumor growth. This probiotic cocktail is already marketed in various forms of food supplement. Present report reveals the transition of M2 to M1 like state of macrophage cells of mouse origin in vitro, ex vivo and in vivo following treatment with the established probiotic cocktail. Current study for the first time suggests the ability of a probiotic formulation to polarize macrophages from M2 to M1 state with potentials of developing newer intervention strategies for tumor growth. As a validation of our claim, we have established a novel and significant way of tumor inhibition in mouse model by the probiotic formulation that is capable of polarizing macrophages from M2 to M1.

This work aimed to isolate and identify Streptococcus and Lactobacillus species from raw cow’s milk obtained from Southwest Paraná - Brazil. We used randomly amplified polymorphic DNA (RAPD)-PCR to identify and type 58Streptococcus and 48 Lactobacillus isolates, of which 04 Streptococcus thermophilus and 02 Streptpcoccus macedonicus were confirmed by species-specific PCR and by sequencing of the 16S ribosomal RNA of 02Streptococcus lutetiensis/infantarius, 10 Lactobacillus fermentum, 03 Lactobacillus delbrueickii subspecies bulgaricus, 01 Lactobacillus rhamnosus/casei and 02 Lactobacillus helveticus. The results indicated predominance of Streptococcus thermophillus and Lactobacillus fermentum. Streptococcus thermophilus and Lactobacillus delbrueickii subspecies bulgaricus strains were tested on the basis of their acidification kinetics. Considerable variation between the Streptococcus thermophilus was observed for the maximum rate of acidification (Vm), with a maximum of -4.5 and mi...

Formulations using cassava starch or inulin plus milk were fermented with three different lactic acid bacteria (LAB) strains: Lactobacillus plantarum D34, Lactobacillus sp. SLH6, and Streptococcus thermophilus ST4. Growth and acidification were followed in 3% powdered milk (M3), 3% milk-6% starch (M3-S6), and 3% milk-6% inulin (M3-In6). D34 and SLH6 growth was enhanced by starch in M3-S6, when compared to the count (CFU/ml) obtained in M3. Growth of all strains was promoted by inulin. All fermented products showed LAB counts of 8.0 log or higher. Carbohydrate utilization was in agreement with growth and acidification results. The highest increase in CFU in rat feces was observed in M3-S6 fermented with ST4; the D34 fermented product also increased CFU but SLH6 did not, either with starch or inulin. This suggests that ST4 and D34 strains provide a good choice to ferment the proposed formulations in order to obtain a marked improvement of natural intestinal flora.

Water kefir is a beverage product from fermented lactic acid and yeast bacteria. Water kefir salakpondoh has the potential to have high antioxidant activity because has a high phenol content. The purpose of this study was to determine the antioxidant level and sifaet organoleptic water kefir pondohzalacca with the addition of palm sugar which was examined from the starter concentration and different fermentation time. The method used in this study is experimental research using a completely randomized design (CRD) with 2 factorials and repeated twice. The treatment factors used were variations in water kefir starter concentration (6%, 8% and 10%) and long fermentation variations (24 jm and 36 hours). The best treatment results with the highest antioxidant activity were at a concentration of 6% with 36 hours fermentation time which was 5.09 wb and the lowest results were found at a concentration of 3% with a 24hour fermentation period of 1.92 wb. Based on the parameters tested, the c...

In two sets of experiments the immobilized cells of the wine yeast Saccharomyces cerevisiae and the mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus were dried and tested for storage ability at 4°C. Both κ-carrageenan and alginate were used as entrapment matrices. The beads with the cells were either dried right after immobilization or activated prior drying. Air flow over a flat bed of beads was employed as the drying method. For S. cerevisiae the best results were attained with the primarily activated (activation prior drying) alginate entrapped cells. This corresponds to 69•5% activity retention measured as ethanol productivity at the end of 7 weeks of storage based on the activity of the non-dried beads. For the lactic acid bacteria mixed culture, no activity was detected for the directly dried beads. For the primarily activated (activation prior drying) cells, it was observed that upon drying the activities of κ-carrageenan and alginate entrapped cells decreased to about 77 and 73%, respectively, after 36 days of storage taking non-dried beads as a reference in terms of lactic acid production. For both matrices primarily activated beads required longer period of drying over directly dried ones.

The lactic acid bacterium Streptococcus thermophilus is widely used as a starter culture for the production of dairy products. Whole-genome sequencing is expected to utilize the genetic basis behind the metabolic functioning of lactic acid bacterium (LAB), for development of their use in biotechnological and probiotic applications. We sequenced the whole genome of Streptococcus thermophilus MTCC 5461, the strain isolated from a curd source, by 454 GS-FLX titanium and Ion Torrent PGM. We performed comparative genome analysis using the local BLAST and RDP for 16S rDNA comparison and by the RAST server for functional comparison against the published genome sequence of Streptococcus thermophilus CNRZ 1066. The whole genome size of S. thermophilus MTCC 5461 is of 1.73 Mb size with a GC content of 39.3%. Streptococcal virulence-related genes are either inactivated or absent in the strain. The genome possesses coding sequences for features important for a probiotic organism such as adhesion, acid tolerance, bacteriocin production, and lactose utilization, which was found to be conserved among the strains MTCC 5461 and CNRZ 1066. Biochemical analysis revealed the utilization of 17 sugars by the bacterium, where the presence of genes encoding enzymes involved in metabolism for 16 of these 17 sugars were confirmed in the genome. This study supports the facts that the strain MTCC 5461 is nonpathogenic and harbors essential features that can be exploited for its probiotic potential.

Lactic acid bacteria evolution (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus) from two Romanian fermented dairy products (yoghurt and sana) was followed in tree stages of storage during shelf-life: in first day of storage after processing; in the middle of storage period and in the last day of storage period. An important decrease of lactic acid bacteria was observed to storage during shelf-life. This indicates a low stability of starter culture, viable germs being inhibited by other micro-organisms development (first Enterobacteriaceae then yeast and molds).

This study is to develop Non-dairy Synbiotic Chocolates as an alternative to conventional Chocolate by using a probiotic microorganism (Streptococcus thermophilus BURD PB 8) in combination with varying percentages of oat powder, almond milk, beetroot powder and stevia powder. Additionally, the ratio of oat powder, almond milk, beetroot powder and stevia powder were optimized based on sensory evaluations such as color, flavor/taste, texture, and overall acceptability. A panel of 50 tasters with extensive backgrounds in the Food Science field evaluated the organoleptic qualities of commercially produced control Chocolate (T 0 ) and experimental Non-dairy Synbiotic Chocolates (T 1 , T 2 and T 3 ). The sensory evaluation was place over the course of three days. A 9-point hedonic scale was used to score each attribute, with 9 representing the highest rating and 1 representing the lowest. Following an overall acceptability score, T 2 treatment had a higher score (8.10 ± 0.06 c ) than the T1 score (7.10 ± 0.11 b ) and T3 score (6.00 ± 0.02 d ).

This study investigated the viability of probiotic (Lactobacillus acidophilus LA5, Lactobacillus rhamnosus LBA and Bifidobacterium animalis subsp. lactis BL-04) in milk fermented with Lactobacillus delbrueckii subsp. bulgaricus LB340 and Streptococcus thermophilus TAO (yoghurt -Y). Each probiotic strain was grown separately in co-culture with Y and in blends of different combinations. Blends affected fermentation time(s), pH and firmness during storage at 4°C. The product made with Y plus B. animalis subsp. lactis and L. rhamnosus had counts of viable cells at the end of shelf life that met the minimum required to achieve probiotic effect. However, L. acidophilus and L. delbrueckii subsp. bulgaricus were inhibited.

The associative behaviors of Bifidobacterium lactis (Bl) and Streptococcus thermophilus (St) have been investigated in skim milk through a study based on their growth and organic acid profile. Finally, the effect of inulin was examined, as one of the most attracting prebiotics in functional food preparation, on the fermentation patterns either of pure cultures of Bl and St or of their co-culture. In the presence of inulin, the time that St, Bl and St-Bl lasted to complete fermentation (i.e., to reach pH 4.5) was shorter than in its absence. Biomass growth and levels of lactic and acetic acids and volatile compounds also enhanced in the presence of inulin, showing a positive synbiotic effect between pre-and probiotics.

In Streptococcus thermophilus , the ComRS regulatory system governs the transcriptional level of comX expression and, hence, controls the early stage of competence development. The present work focuses on the posttranslational control of the activity of the sigma factor ComX and, therefore, on the late stage of competence regulation. In silico analysis performed on the S. thermophilus genome revealed the presence of a homolog of mecA ( mecA St ), which codes for the adaptor protein that is involved in ComK degradation by ClpCP in Bacillus subtilis . Using reporter strains and microarray experiments, we showed that MecA St represses late competence genes without affecting the early competence stage under conditions that are not permissive for competence development. In addition, this repression mechanism was found not only to act downstream of comX expression but also to be fully dependent on the presence of a functional comX gene. This negative control was similarly released in stra...