scholarly journals PSIX-14 Influence of living yeast of the genus Rhodotorula against probiotic and pathogenic bacteria

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 414-414
Author(s):  
Daria A Nikanova ◽  
Evgenia Kolodina
Keyword(s):  
Staphylococcus Epidermidis ◽  
Growth And Development ◽  
Lactobacillus Casei ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Yeast Cells ◽  
Cultivation Temperature ◽  
E Coli ◽  
Broth Dilution

Abstract The aim of the research was to study the effect of live yeast Rhodotorula spp. (LYR) on the growth and development of microorganisms and microbial profiles in batch culture. A liquid medium was used to prepare the inoculum (20 g/L glucose, 20 g/L peptone, 10 g/L yeast extract). The study in vitro was a 3×5 factorial arrangement, including low (5.0) and high media pH (7.5) and temperature (from 20 to 39 ° C). The treatments were LYR with concentrations from 1·103 to 1·1011 CFU/ml. The bacteria were selected: Lactobacillus casei subsp. Rhamnosus ATCC 7469, Bifidobacterium breve ATCC 15701, E. coli ATCC 25922, Staphylococcus aureus ATCC 25923, Staphylococcus epidermidis ATCC 14990. The analyses were carried out separately for each culture and LYR concentration by broth dilution. For incubation were used Saburo agar for LYR and differential-diagnostic media for each bacterial species. After incubation, there was a lack of growth of E. coli, S. aureus and S. epidermidis in LYR concentrations from 1·109 to 1·1011 CFU/ml at the temperature of 28±0.5 °С, while the number of yeast cells did not decrease. At the temperature above 32±0.5 °C there was a decrease in the amount of LYR by more than 1000-fold in the samples of all cultures. The presence of LYR in the medium led to an increase (p≤0.001) in the number of L. casei at pH 5.0 and temperature less than 30±0.5 °С. Unlike L. casei, the viability of the B. breve culture has decreased (P ≤0.05) by 200 times at pH 5.0, but has increased (p≤0.001) by more than 1000 times at pH 7.0. The optimal cultivation temperature was 36±0.5 °С. These results indicate the multidirectional effect of LYR on microorganisms in vitro. This work was supported by the Ministry of Science and Higher Education of Russia (topics GZ AAAA-A18-118021590136-7).

scholarly journals Determinación de la cinética, pruebas de crecimiento y efecto de inhibición in vitro de Lactobacillus casei en Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae y Escherichia coli

2015 ◽  
Vol 62 (2) ◽  
Author(s):  
Henry Jurado-Gámez ◽  
Manuel Gúzman-Insuasty
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Streptococcus Agalactiae ◽  
Staphylococcus Epidermidis ◽  
Lactobacillus Casei ◽  
E Coli

<p>Se determinó la cinética, pruebas de crecimiento y el efecto de inhibición <em>in vitro</em> de <em>Lactobacillus casei</em> sobre <em>Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae </em>y<em> Escherichia coli</em>. Se usaron cepas de casa comercial y cepas aisladas en la Vereda La Victoria, Corregimiento de Catambuco al suroccidente del municipio de Pasto, Nariño, Colombia. Se evaluó el efecto de los antibióticos Dicloxacilina, Cefepima, Cefalotina, Ciprofloxacina, Gentamicina, Penicilina, Trimetropim Sulfa y Ampicilina. Se evaluó la inhibición producida por <em>L. casei</em> y su sobrenadante sobre las bacterias patógenas. El crecimiento de la bacteria láctica se evaluó con tres niveles de pH (2,5, 4,5 y 7),  tres concentraciones de sales biliares (0,5, 1 y 2%) y dos de bilis bovina (1 y 1,2%), y dos temperaturas (38 y 45°C). Igualmente se determinó la cinética de crecimiento y las variables pH, azúcar total, proteína y ácido láctico.  Mediante HPLC se determinaron los péptidos y los ácidos orgánicos presentes en el sobrenadante. <em>L. casei </em>mostró susceptibilidad a la Ciprofloxacina y Ampicilina, mientras que <em>S. aureus </em>mostró susceptibilidad y resistencia a todos los antibióticos para la cepa comercial y aislada respectivamente, el mismo comportamiento se presentó con <em>S. epidermidis</em>. Las cepas de <em>S. agalactiae</em> y <em>E. coli</em> aisladas y comerciales mostraron susceptibilidad a los antibióticos.  La cepa láctica mostró un efecto de inhibición de <em>S. aureus</em>, <em>S. epidermidis</em> y  <em>S. agalactiae</em>, pero no fue efectiva con <em>E. coli</em>, igual comportamiento se observó con el uso del sobrenadante de la bacteria láctica. Se encontró crecimiento de 1 x 10<sup>10</sup> y 5,1 x 10<sup>7</sup> UFC/ml para 1 y 1,2 % de bilis bovina; 2,3 x 10<sup>7</sup>, 1 x 10<sup>9</sup> y 3 x 10<sup>8</sup> UFC/ml para 0,5, 1 y 2 % de sales biliares respectivamente; 1,1 x 10<sup>11</sup>, 2,0 x 10<sup>10</sup> y 1,0 x 10<sup>10</sup> UFC/ml para  pH de 2,5, 4,5 y 7 respectivamente. La fase exponencial se encontró a 16:48 horas con un crecimiento de 3 x 10<sup>10</sup> UFC/ml. La variables pH, azúcar, acidez y proteína durante la fase exponencial fueron de 4,94, 0,88 mg/l, 2,89 mg/l y 1,9 mg/l, respectivamente. La prueba de HPLC para péptidos mostró la presencia de una cadena VAL-TIR-VAL y para ácidos orgánicos se encontró una producción de 83,46% de ácido láctico. <em>L. casei </em> mostró buenas características probiótica que permitirían su aplicación en ensayos in vivo para el control de microorganismos causantes de mastitis subclínica en vacas.</p>

Properties and Biotechnological Application of mutant Derivatives of Mini-intein PRP8 from Penicillium chrysogenum with Improved Control of C-terminal Processing

2019 ◽  
Vol 35 (6) ◽  
pp. 91-101
Author(s):  
F.A. Klebanov ◽  
S.E. Cheperegin ◽  
D.G. Kozlov
Keyword(s):  
Penicillium Chrysogenum ◽  
Protein Denaturation ◽  
Biologically Active ◽  
Cultivation Temperature ◽  
Target Proteins ◽  
E Coli ◽  
Complete Inactivation ◽  
Target Molecules ◽  
Proteins And Peptides

Mutant variants of mini-intein PRP8 from Penicillium chrysogenum (Int4b) with improved control of C-terminal processing were characterized. The presented variants can serve as a basis for self-removed polypeptide tags capable of carrying an affine label and allowing to optimize the process of obtaining target proteins and peptides in E. coli cells. They allow to synthesize target molecules in the composition of soluble and insoluble hybrid proteins (fusions), provide their afnne purification, autocatalytic processing and obtaining mature target products. The presented variants have a number of features in comparison with the known prototypes. In particular the mutant mini-intein Int4bPRO, containing the L93P mutation, has temperature-dependent properties. At cultivation temperature below 30 °C it allows the production of target molecules as part of soluble fusions, but after increasing of cultivation temperature to 37 °C it directs the most of synthesized fusions into insoluble intracellular aggregates. The transition of Int4bPRO into insoluble form is accompanied by complete inactivation of C-terminal processing. Further application of standard protein denaturation-renaturation procedures enable efficiently reactivate Int4bPRO and to carry out processing of its fusions in vitro. Two other variants, Int4b56 and Int4b36, containing a point mutation T62N or combination of mutations D144N and L146T respectively, have a reduced rate of C-terminal processing. Their use in E. coli cells allows to optimize the biosynthesis of biologically active target proteins and peptides in the composition of soluble fusions, suitable for afnne purification and subsequent intein-dependent processing without the use of protein denaturation-renaturation procedures. intein, fusion, processing, processing rate, gelonin The work was supported within the framework of the State Assignment no. 595-00003-19 PR.

Acetate Kinase (AcK) is Essential for Microbial Growth and Betel-derived Compounds Potentially Target AcK, PhoP and MDR Proteins in M. tuberculosis, V. cholerae and Pathogenic E. coli: An in silico and in vitro Study

2019 ◽  
Vol 18 (31) ◽  
pp. 2731-2740 ◽  
Author(s):  
Sandeep Tiwari ◽  
Debmalya Barh ◽  
M. Imchen ◽  
Eswar Rao ◽  
Ranjith K. Kumavath ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
In Silico ◽  
Pathogenic Bacteria ◽  
In Vitro Study ◽  
Docking Studies ◽  
Acetate Kinase ◽  
E Coli ◽  
Pathogenic Escherichia Coli ◽  
Novel Target

Background: Mycobacterium tuberculosis, Vibrio cholerae, and pathogenic Escherichia coli are global concerns for public health. The emergence of multi-drug resistant (MDR) strains of these pathogens is creating additional challenges in controlling infections caused by these deadly bacteria. Recently, we reported that Acetate kinase (AcK) could be a broad-spectrum novel target in several bacteria including these pathogens. Methods: Here, using in silico and in vitro approaches we show that (i) AcK is an essential protein in pathogenic bacteria; (ii) natural compounds Chlorogenic acid and Pinoresinol from Piper betel and Piperidine derivative compound 6-oxopiperidine-3-carboxylic acid inhibit the growth of pathogenic E. coli and M. tuberculosis by targeting AcK with equal or higher efficacy than the currently used antibiotics; (iii) molecular modeling and docking studies show interactions between inhibitors and AcK that correlate with the experimental results; (iv) these compounds are highly effective even on MDR strains of these pathogens; (v) further, the compounds may also target bacterial two-component system proteins that help bacteria in expressing the genes related to drug resistance and virulence; and (vi) finally, all the tested compounds are predicted to have drug-like properties. Results and Conclusion: Suggesting that, these Piper betel derived compounds may be further tested for developing a novel class of broad-spectrum drugs against various common and MDR pathogens.

scholarly journals Enhancing Terpene Yield from Sugars via Novel Routes to 1-Deoxy-d-Xylulose 5-Phosphate

2014 ◽  
Vol 81 (1) ◽  
pp. 130-138 ◽  
Author(s):  
James Kirby ◽  
Minobu Nishimoto ◽  
Ruthie W. N. Chow ◽  
Edward E. K. Baidoo ◽  
George Wang ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Xylose Reductase ◽  
Pentose Phosphate ◽  
Terpene Biosynthesis ◽  
Content Type ◽  
E Coli ◽  
Pathway Expression ◽  
Terpene Synthesis ◽  
Selection For

ABSTRACTTerpene synthesis in the majority of bacterial species, together with plant plastids, takes place via the 1-deoxy-d-xylulose 5-phosphate (DXP) pathway. The first step of this pathway involves the condensation of pyruvate and glyceraldehyde 3-phosphate by DXP synthase (Dxs), with one-sixth of the carbon lost as CO2. A hypothetical novel route from a pentose phosphate to DXP (nDXP) could enable a more direct pathway from C5sugars to terpenes and also circumvent regulatory mechanisms that control Dxs, but there is no enzyme known that can convert a sugar into its 1-deoxy equivalent. Employing a selection for complementation of adxsdeletion inEscherichia coligrown on xylose as the sole carbon source, we uncovered two candidate nDXP genes. Complementation was achieved either via overexpression of the wild-typeE. coliyajOgene, annotated as a putative xylose reductase, or via various mutations in the nativeribBgene.In vitroanalysis performed with purified YajO and mutant RibB proteins revealed that DXP was synthesized in both cases from ribulose 5-phosphate (Ru5P). We demonstrate the utility of these genes for microbial terpene biosynthesis by engineering the DXP pathway inE. colifor production of the sesquiterpene bisabolene, a candidate biodiesel. To further improve flux into the pathway from Ru5P, nDXP enzymes were expressed as fusions to DXP reductase (Dxr), the second enzyme in the DXP pathway. Expression of a Dxr-RibB(G108S) fusion improved bisabolene titers more than 4-fold and alleviated accumulation of intracellular DXP.

scholarly journals In Vitro Time-Kill of Common Ocular Pathogens with Besifloxacin Alone and in Combination with Benzalkonium Chloride

2021 ◽  
Vol 14 (6) ◽  
pp. 517
Author(s):  
Joseph Blondeau ◽  
Heleen DeCory
Keyword(s):  
Staphylococcus Epidermidis ◽  
Benzalkonium Chloride ◽  
Bacterial Species ◽  
Drug Resistant ◽  
Resistance Development ◽  
Aureus Isolate ◽  
Killing Activity ◽  
Time Kill ◽  
Variable Impact

Background: Besifloxacin ophthalmic suspension 0.6% (w/v%) contains benzalkonium chloride (BAK) as a preservative. We evaluated the in vitro time-kill activity of besifloxacin, alone and in combination with BAK, against common bacteria implicated in ophthalmic infections. Methods: The activity of besifloxacin (100 µg/mL), BAK (10, 15, 20, and 100 µg/mL), and combinations of besifloxacin and BAK were evaluated against isolates of Staphylococcus epidermidis (n = 4), Staphylococcus aureus (n = 3), Haemophilus influenzae (n = 2), and Pseudomonas aeruginosa (n = 2) in time-kill experiments of 180 min duration. With the exception of one S. aureus isolate, all of the staphylococcal isolates were methicillin- and/or ciprofloxacin-resistant; one P. aeruginosa isolate was ciprofloxacin-resistant. The reductions in the viable colony counts (log10 CFU/mL) were plotted against time, and the differences among the time–kill curves were evaluated using an analysis of variance. Areas-under-the-killing-curve (AUKCs) were also computed. Results: Besifloxacin alone demonstrated ≥3-log killing of P. aeruginosa (<5 min) and H. influenzae (<120 min), and approached 3-log kills of S. aureus. BAK alone demonstrated concentration-dependent killing of S. epidermidis, S. aureus and H. influenzae, and at 100 µg/mL produced ≥3-log kills in <5 min against these species. The addition of BAK (10, 15, and 20 µg/mL) to besifloxacin increased the rate of killing compared to besifloxacin alone, with earlier 3-log kills of all species except P. aeruginosa and a variable impact on S. aureus. The greatest reductions in AUKC were observed among H. influenzae (8-fold) and S. epidermidis (≥5-fold). Similar results were found when the isolates were evaluated individually by their resistance phenotype. Conclusions: In addition to confirming the activity of 100 µg/mL BAK as a preservative in the bottle, these data suggest that BAK may help besifloxacin to achieve faster time-kills on-eye in the immediate timeframe post-instillation before extensive dilution against bacterial species implicated in ophthalmic infections, including drug-resistant S. epidermidis. Greater killing activity may help prevent resistance development and/or help treat resistant organisms.

scholarly journals IN VITRO MICROBIAL TIME-KILLING CURVE FOR NEWLY SYNTHESIZED AMINOACETYLENIC-2-MERCAPTOBENZOTHIAZOLE COMPOUND

2017 ◽  
Vol 9 (10) ◽  
pp. 125
Author(s):  
Aseel Alsarahni ◽  
Zuhair Muhi Eldeen ◽  
Elham Al-kaissi ◽  
Hiba Al-malliti
Keyword(s):  
Minimum Bactericidal Concentration ◽  
Viable Count ◽  
Broth Culture ◽  
Dilution Method ◽  
Time Intervals ◽  
Minimum Fungicidal Concentration ◽  
E Coli ◽  
Different Types ◽  
Broth Dilution

Objective: To determine the time needed for killing different types of microorganisms by a newly synthesized 2-mercapto-1,3-benzothiazole derivative in comparison to ciprofloxacin and fluconazole.Methods: The minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) for 2-{[4-(2,6-dimethylPiperidin-1-yl)but-2-yn-1-yl]Sulfanyl}-1,3-benzothiazole(AZ3) compound were determined, using the broth dilution method. The MBC and MFC dilutions were prepared. Broth cultures of Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis), Escherichia coli (E. coli), and Pseudomonas aeruginosa (P. aeruginosa) were incubated at 37 °C for 24 h, and Candida albicans (C. albicans) was incubated at 25 °C for 48 h. 0.1 ml of each broth culture represent 1.5 x 106 CFU/ml was challenged with 9.9 ml broth containing the MBC or MFC concentrations of the AZ3 compound. From each sample at different time intervals, 1 ml was taken and added to 9 ml of sterile distilled water, in order to neutralize the effect of AZ3. Serial dilution was done and a viable count was determined from the appropriate dilutions.Results: The viability of the P. aeruginosa, E. coli, S. aureus, B. subtilis and C. albicans were killed within 3.5 h, 5 h, 24 h, 3 h and 5 h respectively. The time killing curves showed that AZ3 needed longer time for killing S. aureus than the time needed to kill B. subtilis. On the other hand, AZ3 needed a shorter time to kill P. aeruginosa, than the time needed to kill E. coli. In comparison with ciprofloxacin, AZ3 needed a shorter time to kill P. aeruginosa and E. coli, and the same time to kill B. subtilis, while it needed longer time than ciprofloxacin to kill S. aureus. In comparison with fluconazole, AZ3 with lower MFC than fluconazole needed longer time to kill C. albicans.Conclusion: AZ3 showed promising antimicrobial killing activities, in compared with ciprofloxacin and fluconazole, which promoted our interest to investigate the time of killing needed for other 2-mercaptobenzothiazole derivatives against different types of microorganisms.

scholarly journals Discovery and Characterization of Low-Molecular Weight Inhibitors of Erwinia tracheiphila

2020 ◽  
Vol 110 (5) ◽  
pp. 989-998
Author(s):  
Cláudio M. Vrisman ◽  
Loïc Deblais ◽  
Yosra A. Helmy ◽  
Reed Johnson ◽  
Gireesh Rajashekara ◽  
...  
Keyword(s):  
Pseudomonas Syringae ◽  
High Throughput Screening ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Bacillus Species ◽  
Erwinia Tracheiphila ◽  
Static Activity ◽  
Low Toxicity

Plant pathogenic bacteria in the genus Erwinia cause economically important diseases, including bacterial wilt of cucurbits caused by Erwinia tracheiphila. Conventional bactericides are insufficient to control this disease. Using high-throughput screening, 464 small molecules (SMs) with either cidal or static activity at 100 µM against a cucumber strain of E. tracheiphila were identified. Among them, 20 SMs (SM1 to SM20), composed of nine distinct chemical moiety structures, were cidal to multiple E. tracheiphila strains at 100 µM. These lead SMs had low toxicity to human cells and honey bees at 100 µM. No phytotoxicity was observed on melon plants at 100 µM, except when SM12 was either mixed with Silwet L-77 and foliar sprayed or when delivered through the roots. Lead SMs did not inhibit the growth of beneficial Pseudomonas and Enterobacter species but inhibited the growth of Bacillus species. Nineteen SMs were cidal to Xanthomonas cucurbitae and showed >50% growth inhibition against Pseudomonas syringae pv. lachrymans. In addition, 19 SMs were cidal or static against Erwinia amylovora in vitro. Five SMs demonstrated potential to suppress E. tracheiphila when foliar sprayed on melon plants at 2× the minimum bactericidal concentration. Thirteen SMs reduced Et load in melon plants when delivered via roots. Temperature and light did not affect the activity of SMs. In vitro cidal activity was observed after 3 to 10 h of exposure to these five SMs. Here, we report 19 SMs that provide chemical scaffolds for future development of bactericides against plant pathogenic bacterial species.

scholarly journals Combined Action of Human Commensal Bacteria and Amorphous Silica Nanoparticles on the Viability and Immune Responses of Dendritic Cells

2017 ◽  
Vol 24 (10) ◽  
Author(s):  
Giulia Malachin ◽  
Elisa Lubian ◽  
Fabrizio Mancin ◽  
Emanuele Papini ◽  
Regina Tavano
Keyword(s):  
Dendritic Cells ◽  
Silica Nanoparticles ◽  
Amorphous Silica ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Commensal Bacteria ◽  
Content Type ◽  
E Coli ◽  
Synergistic Induction ◽  
Ifn Γ

ABSTRACT Dendritic cells (DCs) regulate the host-microbe balance in the gut and skin, tissues likely exposed to nanoparticles (NPs) present in drugs, food, and cosmetics. We analyzed the viability and the activation of DCs incubated with extracellular media (EMs) obtained from cultures of commensal bacteria (Escherichia coli, Staphylococcus epidermidis) or pathogenic bacteria (Pseudomonas aeruginosa, Staphylococcus aureus) in the presence of amorphous silica nanoparticles (SiO2 NPs). EMs and NPs synergistically increased the levels of cytotoxicity and cytokine production, with different nanoparticle dose-response characteristics being found, depending on the bacterial species. E. coli and S. epidermidis EMs plus NPs at nontoxic doses stimulated the secretion of interleukin-1β (IL-1β), IL-12, IL-10, and IL-6, while E. coli and S. epidermidis EMs plus NPs at toxic doses stimulated the secretion of gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), IL-4, and IL-5. On the contrary, S. aureus and P. aeruginosa EMs induced cytokines only when they were combined with NPs at toxic concentrations. The induction of maturation markers (CD86, CD80, CD83, intercellular adhesion molecule 1, and major histocompatibility complex class II) by commensal bacteria but not by pathogenic ones was improved in the presence of noncytotoxic SiO2 NP doses. DCs consistently supported the proliferation and differentiation of CD4+ and CD8+ T cells secreting IFN-γ and IL-17A. The synergistic induction of CD86 was due to nonprotein molecules present in the EMs from all bacteria tested. At variance with this finding, the synergistic induction of IL-1β was prevalently mediated by proteins in the case of E. coli EMs and by nonproteins in the case of S. epidermidis EMs. A bacterial costimulus did not act on DCs after adsorption on SiO2 NPs but rather acted as an independent agonist. The inflammatory and immune actions of DCs stimulated by commensal bacterial agonists might be altered by the simultaneous exposure to engineered or environmental NPs.

scholarly journals EVALUATION OF ANTIBACTERIAL RESISTANCE OF BIOFILM FORMS OF AVIAN SALMONELLA GALLINARUM TO FLUOROQUINOLONES

2018 ◽  
Author(s):  
Kumar Kamashi ◽  
Mr. Honnegowda ◽  
Mayanna Asha ◽  
Chandrakala Ms.
Keyword(s):  
Pathogenic Bacteria ◽  
Inhibitory Concentration ◽  
Minimum Bactericidal Concentration ◽  
Bacterial Biofilms ◽  
Dilution Method ◽  
Post Inoculation ◽  
Antibacterial Resistance ◽  
Salmonella Gallinarum ◽  
Broth Dilution

Antimicrobial resistance is a growing concern worldwide. The indiscriminate use of antibiotics for a period of time has led to the emergence of antibiotic resistance in pathogenic bacteria. The present study was designed to evaluate the antibacterial efficacy of fluoroquinolone drugs, ciprofloxacin, enrofloxacin, moxifloxacin, sparfloxacin, norfloxacin, pefloxacin and ofloxacin against avian Salmonella gallinarum bacterial biofilms. The study parameters, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and biofilm elimination concentration (BEC) were determined on days 1, 3, 7, 10, 14 and 20 post inoculation for the planktonic (free) and biofilm cells of S. gallinarum by macro broth dilution method. The MIC and MBC values determined on days 1, 3, 7, 10, 14 and 20 for each of the fluoroquinolone drugs against the planktonic and biofilm forms of avian S. gallinarum were found to be non-significant. BEC values determined against the biofilm forms of S. gallinarum during the study period were found to be non-significant among the tested fluoroquinolones. The results of the present study demonstrated that fluoroquinolone drugs were effective in vitro against both the planktonic and biofilm forms of avian S. gallinarum.

scholarly journals Lactic Acid Bacteria (Lactobacillus bulgaricus and Streptococcus thermophillus) in Yogurt Inhibit the Growth of Escherichia coli, Salmonella typhimurium, and Shigella sp. In Vitro

2021 ◽  
Vol 31 (4) ◽  
pp. 2
Author(s):  
IDSAP Peramiarti
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Salmonella Typhimurium ◽  
Pathogenic Bacteria ◽  
Test Method ◽  
P Value ◽  
E Coli ◽  
Significant Difference

Diarrhea is defecation with a frequency more often than usual (three times or more) a day (10 mL/kg/day) with a soft or liquid consistency, even in the form of water alone. Pathogenic bacteria, such as Escherichia coli, Salmonella typhimurium, and Shigella sp., play a role in many cases, to which antibiotics are prescribed as the first-line therapy. However, since antibiotic resistance cases are often found, preventive therapies are needed, such as consuming yogurt, which is produced through a fermentation process by lactic acid bacteria (LAB). This research aimed to determine the activity of lactic acid bacteria (Liactobacillus bulgaricus and Streptococcus thermophilus) in yogurt in inhibiting the growth of the pathogenic bacteria E. coli, S. typhimurium, and Shigella sp. The research applied in vitro with the liquid dilution test method and the true experimental design research method with post-test-only and control group design. The design was used to see the inhibitory effect of yogurt LAB on the growth of E. coli, S. typhimurium, and Shigell sp. to compare the effect of several different yogurt concentrations, namely 20%, 40%, 60%, and 80%. The results of the Least Significance Different analysis showed that there was a significant difference between yogurt with a concentration of 0% and that with various concentrations in inhibiting the growth of E. coli, S. typhimurium, and Shigella sp. with a p-value of &lt;0.05. Whereas, there was no significant difference in the various concentrations of yogurt in inhibiting the growth of the three kinds of bacteria with a p-value of &gt; 0.05.<p class="Default" align="center"> </p>

Sign in / Sign up

Export Citation Format

Share Document