Lactobacillus Delbrueckii Ssp Research Articles

Digestive characteristics of extracellular polysaccharide from Lactiplantibacillus plantarum T1 and its regulation of intestinal microbiota

This study assessed the potential prebiotic characteristics of the previously reported Lactiplantibacillus plantarum extracellular polysaccharide (EPS-T1) with immunological activity. EPS-T1 was a novel heteropolysaccharide composed of glucose and galactose (1.00:1.21), with a molecular weight of 1.41 × 106 Da. The monosaccharide composition, molecular weight, fourier transform infrared, and 1H NMR analysis showed that EPS-T1 was well tolerated in the simulated oral cavity, gastric fluid, and small intestinal fluid environments, and was not easily degraded. Meanwhile, EPS-T1 could effectively be used as a carbon source to promote the growth of beneficial Lactobacillus species (Lactobacillus delbrueckii ssp. Bulgaricus, Streptococcus thermophilus, Lacticaseibacillus rhamnose GG, Lactiplantibacillus plantarum, Lacticaseibacillus paracasei and Lactobacillus reuteri). After 24 h of fecal fermentation, EPS-T1(5 mg/mL) effectively reduced the relative abundance of harmful bacteria such as the Escherichia-Shigella, Citrobacter, Fusobacterium, Parasutterella, and Lachnoclostridium. While, the level content of beneficial flora (Bacteroides, Blautia, Phascolarctobacterium, Bifidobacterium, Parabacteroides, and Subdoligranulum) were significantly increased. In addition, EPS-T1 was able to significantly promote the enrichment of short-chain fatty acids such as acetic acid, propionic acid and butyric acid. These results provide some basis for the functional application of EPS-T1 as a potential prebiotic.

Microstructure of the organs of the digestive canal of <i>Clarias gariepinus</i> against the background of the use of probiotics

The African clary catfish is an exotic fish, so its breeding in our climate is carried out in closed water supply systems. The microbiota that is located in the gastrointestinal tract consists of various bacteria, and among them the most common are enterococci, lactobacilli, bifidobacteria, etc. They perform a number of functions, such as participation in digestion, synthesis of vitamins, preventing the proliferation of pathogenic microorganisms, etc. d. The purpose of our work is to study the effect of dietary supplements on the degree of development and microstructure of the digestive canal organs of Clarias gariepinus fry. The material for the study was marbled catfish fry 30 and 60 days old, which were divided into three experimental groups according to the principle of analogue pairs. For a month after hatching, they were fed with food with the addition of a dry lyophilized culture of the Lactobacillus delbrueckii ssp complex. bulgaricus with Bifidobacterium lactis, as well as a probiotic with Enterococcus faecium. At the end of the experiment, histological studies of the digestive canal organs were carried out using our improved method. The results of histological studies showed that, against the background of the use of probiotic feed additives of various compositions, changes in the structure of the wall of the esophagus and stomach of experimental fry are observed. In the epithelial plate of the esophageal wall, against the background of the use of a complex of lactoand bifidobacteria, the number of mucous and chloride cells visually increases. The degree of development of gastric glands after adding Enterococcus faecium to the feed is more pronounced by 30 days of age, and in 2-month-old fry their number is visually greater in fish using a complex of lactoand bifidobacteria. The study of the microstructure of organs proves that the use of these biological additives has a positive effect on the growth and development of the digestive tract organs of the African clariid catfish.

Isolation, identification and probiotic potential of lactic acid bacteria and yeasts from commercial yogurt and homemade non-dairy fermented food “KANJI”

South Asian cuisines encompasses a rich variety of traditional fermented foods, which hold great promise as sources of probiotic bacteria with notable health benefits. This study aimed to isolate and characterize probiotic strains from homemade plant-based fermented foods (kanji drink and rice kanji) and commercial dairy-based probiotics (sweetened and probiotic yogurt). The samples were found safe for consumption, devoid of indicator microorganisms and hemolytic activity. They exhibited a diverse microflora with substantial microbial counts (>106 CFU/ml), identified as yeasts and lactic acid bacteria (LAB) namely Lactobacillus curvatus, Leuconostoc mesenteroids, Lactobacillus delbrueckii ssp lactis, Lactobacillus plantarum, and Lactobacillus delbrueckii. Antimicrobial activity tests against six foodborne pathogens demonstrated significant reductions in their growth, highlighting the broad-spectrum antimicrobial potential of the probiotic isolates against gram-positive and gram-negative bacteria. The mixed consortium of samples showed higher growth inhibition compared to individual isolates, emphasizing the importance of microbial diversity in probiotic formulations. The samples' mix consortiums also displayed high auto-aggregative (42.36%–75%) and co-aggregative abilities (up to 93%) with the pathogens over time, with sweetened yogurt showing the highest co-aggregation percentage. The antimicrobial activity of the mix consortiums correlated positively with auto-aggregative capability but negatively with co-aggregative capability, although these correlations were not statistically significant. Consumer acceptance tests, using a nine-point hedonic scaling, favored commercial yogurts over homemade kanji, with sweetened yogurt receiving the highest scores. In conclusion, this study provides insights into the safety, quality, microbial characteristics, antimicrobial activity, aggregative capability, and consumer acceptance of both commercial yogurt and homemade kanji. Considering the limitations of dairy-based probiotics and the growing popularity of vegetarian diets, promoting the consumption of homemade plant-based fermented foods like kanji, which offer wholesome nutrition and potential probiotic benefits, is recommended. Future research should focus on characterizing the in-vivo probiotic potential and standardizing formulations based on consumer demands.

Physicochemical and microbiological properties of Arabic flatbread produced from wild natural sour starters

Background and objectivesExtensive research studies worldwide have discussed and analyzed the sourdough nutritional, chemical, and biotechnological aspects of western types of bread. However, the literature on sourdough usage in Arabic bread processing is very limited. The present study aimed to come up with a new fermentation technique at the bakery level. The new technique is hoped to reveal the traditional nostalgic characteristic flavor of Arabic bread produced using natural sourdough instead of the traditional yeasted dough and study its effect on the resulting bread. Three types of flour (straight grade, whole wheat, and rye) that are ordinarily used in Jordan were used to prepare three natural sour starters using the backslopping technique. FindingsDominant yeast species isolated from the traditional sour starter of the local Jordanian whole wheat were Saccharomyces cerevisiae, Candida glabrata, and Zygosaccharomyces spp., while rye and straight-grade starters showed different domination patterns. The dominant species of lactic acid bacteria (LAB) isolated from the traditional sour starter of the local Jordanian whole wheat (Horani cultivar) were Lactiplantibacillus plantarum2, Lactobacillus delbrueckii ssp bulgaricus, and the Lacticaseibacillus paracasei ssp paracasei3, while mixed strains of LAB isolates were obtained for the rye and straight-grade flour starters on day 7 of preparation.The pH results showed no significant differences (P > 0.05) between the three types of sour starters, while the total titratable acidity (TTA) results showed a significant increase (P ≤ 0.05) in whole wheat sour starters with a TTA value of 11.17 ± 0.11 ml 0.1 N NaOH/10g dough. The 20% and 30% straight-grade sour bread samples and the control exhibited the highest scores in terms of acceptability and total quality scores. ConclusionsThe incorporation of sourdough in Arabic flatbread processing showed remarkable results in extending the shelf life by using natural ingredients, improving the quality, and providing tastier and more convenient bread.

Determining the effect of apple and banana powders dried by sublimation on the quality indicators of a sour milk dessert during storage

The shelf life of sour milk dessert has been substantiated based on the results of this study into the indicators of active acidity, water activity, enthalpy, and organoleptic properties. In addition, the content analysis of lactic acid bacteria and microbiological indicators in the finished product during storage was performed. It was found that the introduction of sublimated fruits together with whey protein concentrate reduces the water activity index from 0.984 to 0.972 by increasing the concentration of solids and product viscosity. The active acidity indicator acts in combination with the water activity on the shelf life of food products. Active acidity during the study period was in the range of 5.4‒4.2 pH units. The biological and physiological value of the fermented milk product will increase due to the use of a starter culture containing microorganisms of bifidobacteria and lactobacilli, which include Streptococcus thermophilus, Lactobacillus delbrueckii ssp. Bulgaricus, Lactobacillus acidophilus, Bifidobacterium lactis, Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillus paracasei, Bifidobacterium infantis. When storing sour milk dessert for more than 3 days, the number of bacteria came down and was 1.0×108 CFU/g on day 9, which meets the regulatory requirements. Based on the results of microbiological indicators, the shelf life of the sour milk dessert was established, which should not exceed 5 days at a temperature of 4±2 °С. The development and improvement of sour milk desserts using secondary milk raw materials is a promising area of scientific research. This would allow the development of waste-free technologies with the maximum use of useful components that are included in the secondary milk raw materials

The Effect of Exopolysaccharide Producer Pediococcus Damnosus 2.6 and Yoghurt Starter Cultures on Ethanol Content, Some Physicochemical and Sensory Properties of Oat Boza

Cereal-based fermented beverages like boza are known functional and probiotic foods. Boza is manufactured by yeast and lactic acid bacteria fermentation of only ones or mixture of various cereals. In this research, the effects of sugar, different microorganisms and inoculum ratios on physicochemical, nutritional and sensory characteristics of oat based boza were investigated. For this purpose, oat based boza production was carried out by 3 different of inoculation rates (0, 3 and 5%) of 3 starter cultures ( Pediococcus damnosus 2.6, Streptococcus thermophilus and Lactobacillus delbrueckii ssp . bulgaricus) . The usage aim of Pediococcus damnosus 2.6 and yoghurt starter cultures was for the production of exopolysaccharide and lactic acid. As a result of using mixed culture and rising inoculation rates stimulated fermentation activity in formulation of boza. Thus, the amount of total solid matter was reduced and increased the contents of ash, protein and mineral matter of oat boza samples. Although the lowest viscosity was determined in Pediococcus damnosus 2.6 inoculation, the most uniform texture was provided. Raw oat had unpleasant odor and flavor but fermentation enhanced sensorial properties of oats. The highest overall acceptance score was observed in oat boza with 3% of yoghurt starter cultures.

Investigation of the probiotic properties and the acid production rate of strains Lactobacillus delbrueckii ssp. Bulgaricus

The antimicrobial activity of strains Lactobacillus delbrueckii ssp. bulgaricus MG1, Lactobacillus delbrueckii ssp. bulgaricus MG2, Lactobacillus delbrueckii ssp. bulgaricus MG3 and Lactobacillus delbrueckii ssp. bulgaricus MG4 has been investigated against pathogenic microorganisms Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 8739, Listeria monocytogenes, Salmonella sp. by the agar well diffusion method. The biomass, the culture medium and the cell-free supernatant were tested. The antibiotic resistance of the strains against clinical practice antibiotics with different mechanisms of action has been determined. The maximum specific growth rate and the parameters of the respective models for the selected strains was determined. The experiments established that Lactobacillus delbrueckii ssp. bulgaricus MG 3 exhibits the most pronounced antimicrobial activity compared to the other strains tested. Practical applicationsThis study was called for by the need to produce starter cultures with established purity and activity for use in the food industry. The aim of this work is to investigate a certain group of lactic acid bacteria widely used in practice and in the composition of starter cultures.

Experimental Design for Removal of Fe(II) and Zn(II) Ions by Different Lactic Acid Bacteria Biomasses

This paper investigates the removal of iron and zinc from aqueous solution with dairy wastewaterin three different biomasses such as Lactobacillus delbrueckii ssp bulgaricus (Lb-12), Streptococcus thermophillus(STM-7) and a combination of both this bacteria culture (YC-380) and the optimization of removal efficiencyusing MINITAB program. A full 23 factorial design of experiments was applied to determine the optimumconditions of removal of Fe(II) and Zn(II) from aqueous solution. The three tested factors were biomassconcentration (5-15 g/L), pH (3-9), and temperature (20-40 °C). The optimum biomass concentration, pH andtemperature were found to be 15 g/L, 9 and 20 °C, respectively. Under optimal value of process parameters, 90-100% Fe(II) and 70-90% Zn(II) removal were obtained with all tested biomasses. Removal results indicated thata combination of both this bacteria might be a promising biomass alternative to ST-M7 and Lb.12 in removingZn(II) and Fe(II) ions from waters.

Biochemical and thermal properties of β-galactosidase enzymes produced by artisanal yoghurt cultures

Abstract β-Galactosidases, produced by pure and mixed cultures of Streptococcus thermophilus 95/2 (St 95/2) and Lactobacillus delbrueckii ssp bulgaricus 77 (Lb 77) isolated from the Toros mountain region of Turkey, were characterised with respect to their biochemical and thermal properties. Optimum pH and temperature for maximum activity were determined and these enzymes were stable in the pH range 7–9 and in the temperature range 20–37 °C, retaining 80–90% of their initial activities. The inactivation energies of β-galactosidase from Lb 77, St 95/2 and mixed culture (Lb 77 and St 95/2) were 51.3, 44.0 and 48.3 kcal mol−1, respectively. Moreover, thermodynamic (ΔG, ΔS, ΔH) and kinetic constants (Km and Vmax) were determined and effects of metal ions were investigated. As a result, these enzymes could be considered as potential candidates for lactose hydrolysis of milk and milk products.

ACE-inhibitory activity of probiotic yoghurt

In this study, the in vitro angiotensin-converting enzyme (ACE)-inhibitory (ACE-I) activity of peptide fractions from different yoghurt batches was assessed. Inhibition of ACE activity resulted in an overall antihypertensive effect. Yoghurts were prepared either using a sole yoghurt culture including Lactobacillus delbrueckii ssp . bulgaricus Lb1466 and Streptococcus thermophilus St1342, or L. acidophilus L10, L. casei L26 and Bifidobacterium lactis B94 in addition to yoghurt culture. ACE-I activity was determined at weekly intervals during 28 days of cold storage. Peptide fractions showing high ACE-I activity were further purified using multiple-steps of RP-HPLC. All probiotic yoghurts showed appreciable ACE-I activity during initial stages of storage compared with the control yoghurt, with a significant ( p<0.05) decrease afterwards. The ACE-I activity ranged from IC 50 of 103.30–27.79 μg mL −1 with the greatest ACE inhibition achieved during first and third week of storage. The in vitro ACE-I activity could be related to the peptide liberation via degradation of caseins. In total, 8 ACE-I peptides were characterized originating from α s2-casein (1), κ-casein (2) and β-casein, of which two well-known ACE-inhibiting peptides, namely Val–Pro–Pro (VPP) and Ile–Pro–Pro (IPP), were identified. These peptides are already used in commercial products.

The complete genome sequence ofLactobacillus bulgaricusreveals extensive and ongoing reductive evolution

Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) is a representative of the group of lactic acid-producing bacteria, mainly known for its worldwide application in yogurt production. The genome sequence of this bacterium has been determined and shows the signs of ongoing specialization, with a substantial number of pseudogenes and incomplete metabolic pathways and relatively few regulatory functions. Several unique features of the L. bulgaricus genome support the hypothesis that the genome is in a phase of rapid evolution. (i) Exceptionally high numbers of rRNA and tRNA genes with regard to genome size may indicate that the L. bulgaricus genome has known a recent phase of important size reduction, in agreement with the observed high frequency of gene inactivation and elimination; (ii) a much higher GC content at codon position 3 than expected on the basis of the overall GC content suggests that the composition of the genome is evolving toward a higher GC content; and (iii) the presence of a 47.5-kbp inverted repeat in the replication termination region, an extremely rare feature in bacterial genomes, may be interpreted as a transient stage in genome evolution. The results indicate the adaptation of L. bulgaricus from a plant-associated habitat to the stable protein and lactose-rich milk environment through the loss of superfluous functions and protocooperation with Streptococcus thermophilus.

English

The contribution of selected ropy and capsular Lactobacillus plantarum 162RM on texture of fermented milk as well as on the functionality of kareish cheese was established in this study. The cell suspension of this strain was used in combination with commercial starter cultures MY900 ( Lactobacillus delbrueckii ssp. Bulgaricus/I> and Streptococcus thermophilus ) and MM100 ( Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. cremoris and Lactococcus lactis ssp. diacetyllactis ) obtained from Rhodia Food to manufacture fermented milk and Kareish cheese respectively. The final pH of fermented milks manufactured with the combination of starter MY900 and different concentration of strain L. plantarum 162RM were not significantly different. Fermented milk hardness, consistency, and adhesiveness increased significantly when 8 % (V/V) of strain Lactobacillus plantarum 162RM was used. This strain produces exopolysaccharides (EPS), which by attaching to the casein matrix increases and improves the texture characteristics of fermented milk. The Experimental Kareish Cheese (EKC), made by pairing commercial starter MM100 with 8% (v/v) of L. plantarum 162RM were also compared to Control Kareich Cheese (CKC) in terms of their moisture content and textural properties. The EKC showed the greatest moisture retention and the use of ropy and capsular strain of L. plantarum 162RM affects significantly some textural properties of EKC cheese, relative to the control. The CKC samples were gummier and more chewy than the EKC fresh samples. It is therefore evident that, used in appropriate amount, this strain can increase moisture content in low fat Kareish cheese leading to improvement of textural properties. Key Words: Fermented milks, kareish cheese, ropy and capsular strain, moisture, textural properties. African Journal of Biotechnology Vol.3(10) 2004: 512-518

Effects of Addition of Sucrose and Salt, and of Starvation upon Thermotolerance and Survival During Storage of Freeze‐dried Lactobacillus delbrueckii ssp bulgaricus

ABSTRACT: Increased survival of freeze‐dried cells of Lactobacillus bulgaricus was observed when the drying medium was supplemented with sucrose; however, the magnitude of such protection was dependent on the growth medium used. Supplementing the growth medium with NaCl markedly increased survival of dried cells, and only a small effect was exerted by the composition of the drying medium or prior to starvation of cells. The D57 values of Lactobacillus bulgaricus cells grown in MRS were about half of those of cells grown in MRS supplemented with sucrose, with sucrose plus NaCl, or with NaCl.

Production of a yogurt‐like product from Lupinus campestris seeds

AbstractA Lupinus campestris milk‐like product was obtained with 6.3% protein by using an alkaline thermal treatment. The colour of the suspension showed a greater similarity to cow's milk than to commercial soymilk. To adjust the carbohydrate concentration and induce fermentation, 3% of sucrose and 1.5% of lactose were added. The product was pasteurized and inoculated with a culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp bulgaricus. A lupin yogurt‐like product with pH 4.02, 0.87% lactic acid, and a lactic acid bacteria count (3.2 × 108 CFU ml−1) and viscosity similar to commercial cow's milk yogurt was obtained. The amino acid composition of the proteins in the lupin milk and yogurt products had a good balance, with the exception, as in other legumes, of the sulphur‐containing amino acids. Sensory evaluation indicated that the product was well accepted by consumers. These results offer a good possibility for the utilization of this legume in human nutrition through the elaboration of products that are analogous to others already present in the commercial market. Copyright © 2003 Society of Chemical Industry

Modelling of rheological, microbiological and acidification properties of a fermented milk product containing a probiotic strain of Lactobacillus paracasei

Abstract The simultaneous effect of fermentation temperature (FT, 36.7–43.4°C), milk total solid level (TS, 11.3–14.7%, w/v) and total inoculum concentration (TI, 2.16–3.84 v/v) on the acidification process and the rheological properties of fermented milk products with Lactobacillus paracasei ssp paracasei B117, Lactobacillus delbrueckii ssp bulgaricus Y 6.15 and Streptococcus thermophilus Y 4.10 was explored by means of response surface methodology. Maximum storage modulus (G′max), minimum loss tangent (tan δmin), rate of gelation (IE) and onset of gelation were the rheological parameters studied. Maximum acidification rate (Vm), time at which maximum acidification rate was observed (Tm), and time to reach the end of fermentation (Te) characterized the kinetics of acidification, whereas the increase in the number of the three bacteria at the end of fermentation was chosen as the microbiological parameter of the system. The growth/survival of microorganisms and the organic acid profile during cold storage as well as the overall product acceptability by a consumer panel were also assessed. TS strongly affected G′max and tan δmin; high TS resulted in large increase in G′max and decrease in tan δmin. Increasing fermentation temperature gave a decrease in the onset of gelation, Vm, Tm and Te, and an increase in the gelation rate (IE). Under conditions of relatively low FT (37–40°C), high TS (about 14%) and high TI (3–4%), relatively high gelation and low acidification rates were observed, fermentation took a longer time to finish, but the formed gels were firmer, showing higher G′max and lower tan δmin values. Low FT (36–38°C) enabled higher increase in the number of L. paracasei B 117. The probiotic strain showed good compatibility with the S. thermophilus Y 4.10 and L. bulgaricus Y 6.15, and satisfactory levels of all bacteria were found during fermentation and storage at 4°C for 21 days. No major differences in lactic and uric acid contents were seen between the control (probiotic strain-free product) and the probiotic fermented milk, whereas the latter contained slightly higher amounts of citric, pyruvic and orotic acids. Moreover, the probiotic fermented milk was graded by the consumer panel with a similar acceptability score as the control product.

Survie des ferments du yaourt dans le tube digestif du lapin

Survival of starters of yogurt in the digestive tract of rabbits . Yogurt presents a probiotic interest for the consumer. Most of its properties are linked to the ingestion of living lactic acid bacteria (starters), some of which can survive during the crossing of the digestive tract. Our study is based on this perspective. The results obtained show that Streptococcus thermophilus(Sc. t.) and Lactobacillus delbrueckiissp. bulgaricus (Lb. b.) were relatively resistant to gastric acid, bile salts and intestinal flora. These starters were found at significant concentrations and at different levels of the digestive tract as the rabbits fed with a standard diet supplemented with yogurt (YB3). After stop- ping addition of the Sc. t. and Lb. b. yogurt to the diet of the rabbits, the number of Sc. t. and Lb. b. re- mained at an acceptable level for 24 h; the numbers were about 10 5 ,1 0 7 cells.mL -1 and 10 7 cells.g -1 wet faeces for the stomach, the duodenum and the large intestine, respectively. Sc. thermophilus / Lb. delbrueckii ssp. bulgaricus / gastric acid / bile salt / intestinal flora

Relationship between carbon catabolite repression and the biosynthesis regulation of the prolidase PepQ from Lactobacillus delbrueckii ssp. bulgaricus CNRZ 397

Lactobacillus delbrueckiissp. bulgaricus CNRZ 397 (L. bulgaricus) displays several enzymes specific of proline-containing peptides. We focused on the prolidase PepQ which specifi- cally cleaves X-Pro dipeptides. PepQ biosynthesis was previously shown to be independent of the pep- tide concentration of the culture medium in contrast to the cell surface proteinase PrtB and several aminopeptidases. Regulation of PepQ biosynthesis can be explained by the genetic organization of the region pepR1-cre-pepQ. The pepR1 gene encodes a CcpA-like regulator and its promoter harbors a cre site located immediately upstream of pepQ. Expression of fusions cre-pepQ-lacZand pepQ-lacZ in Bacillus subtilis showed that, under glucose conditions, the regulator CcpA acts as a transcriptional activator of pepQ expression. Analysis of PepQ biosynthesis in L. bulgaricus cells grown in differ- ent media is in agreement with a regulation dependent on carbohydrates. Lactobacillus delbrueckii ssp. bulgaricus / catabolite repression / PepQ / PepR1