Academic literature on the topic 'Streptococcus sanguis'

ABSTRACT Oral streptococci utilize an F-ATPase to regulate cytoplasmic pH. Previous studies have shown that this enzyme is a principal determinant of aciduricity in the oral streptococcal species Streptococcus sanguis and Streptococcus mutans. Differences in the pH optima of the respective ATPases appears to be the main reason that S. mutans is more tolerant of low pH values than S. sanguis and hence pathogenic. We have recently reported the genetic arrangement for the S. mutans operon. For purposes of comparative structural biology we have also investigated the F-ATPase from S. sanguis. Here, we report the genetic characterization and expression in Escherichia coli of the S. sanguis ATPase operon. Sequence analysis showed a gene order of atpEBFHAGDC and that a large intergenic space existed upstream of the structural genes. Activity data demonstrate that ATPase activity is induced under acidic conditions in both S. sanguis and S. mutans; however, it is not induced to the same extent in the nonpathogenic S. sanguis. Expression studies with an atpD deletion strain of E. coli showed that S. sanguis-E. coli hybrid enzymes were able to degrade ATP but were not sufficiently functional to permit growth on succinate minimal media. Hybrid enzymes were found to be relatively insensitive to inhibition by dicyclohexylcarbodiimide, indicating loss of productive coupling between the membrane and catalytic subunits.

Background: Micro-organisms resistant to most of the commercial antibiotics are rapidly expanding and there is an urgent need for detection of novel antimicrobial compounds. Tooth decay is a dental infection with bacterial sources such as Streptococcus mutans and Streptococcus sanguis. Objectives: The present study aimed to evaluate the in vitro antibacterial effects of different concentrations of Citrus limon peel, pineapple fruit, and pineapple peel extracts on oral pathogens such as S. mutants and S. sanguis. Materials and Methods: In this experimental study, the hydroethanolic extracts of the selected plants were prepared by maceration method and their antibacterial effects were evaluated by agar well diffusion method. Results: Two-fold dilutions of plant extract solutions were tested to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against each selected microorganism. The results of the current study revealed that pineapple peel extracts had the highest antibacterial effect on S. sanguis (MIC: 1.56 mg/mL and MBC: 3.12 mg/mL). Pineapple fruit had the lowest antibacterial activity against S. mutans (MIC: 25 mg/mL and MBC: 100 mg/mL). C. limon peel had significant antibacterial activity against S. mutans and S. sanguis. Conclusion: The peel of C. limon and pineapple had significant antibacterial activity against cariogenic microorganisms such as S. mutans and S. sanguinis.

Although the elaboration of bacteriocins by streptococci has been described previously (Brock & David, 1963; Kuttner, 1966; Kelstrup & Gibbons, 1969; Overturf & Mortimer, 1970; Kramer & Brandis, 1972), few attempts have been made to purify and characterize these bactericidal factors (Kramer & Brandis, 1972). Streptococcus sanguis (strain Challis) produces a streptocin which is lethal for Streptococcus sanguis (strain Wicky) and can be purified by ammonium sulphate fractionation and Sephadex G-100 column chromatography. We exposed sensitive strain Wicky cells to Challis streptocin and observed macromolecular synthesis and membrane permeability.

Background: Dental caries is a major problem in oral cavity. If dental caries causes cavity, the structure of dental hard tissue will not be reversible because of damage in the structure of the hard tissue. The early pathogenesis mechanism of dental caries is an adhesion interaction between cariogenic Streptococcus mutans microorganisms and tooth surface pellicles. The attachment involves a specific molecular component interaction between the bacterial complement molecules and the surface of the host. Streptococcus sanguis as a dominant ecology at the beginning of bacterial plaque aggregation will colonize the tooth surface earlier than S. mutans. The surface of bacterial cells can express some adesin. The bacteria also can express receptors for adhesins of other bacteria. Specific receptors for adhesions of S. Mutans bacteria are not only found in the pellicles, but also present in pioneer bacteria, such as S. sanguis. Adhesion between those bacteria is called as coagregation. Purpose: This study aimed to analyze the characterization of Streptococcus sanguis molecular receptors for Streptococcus mutans binding molecules. Method: This study used a sonication method for protein isolation of S. mutans and S. sanguis bacterial biofilms, as well as electrophoresis method using 12 % SDS-PAGE gel and Western Blot analysis. Result: Results of the protein profile analysis of S. mutans biofilms using 12% SDS-PAGE showed that there were 17 bands, each of which molecular weights was 212, 140, 81, 65, 61, 48, 45, 44, 40, 39, 33 , 25, 23, 19, 17, 12, and 11 kDa. On the other hand, results of the protein profile analysis of S. sanguis biofilms using 12% SDS-PAGE showed that there were 15 bands, each of which molecular weight was 130, 85, 65, 61, 48, 46, 40, 37, 29, 25, 23, 21, 17, 15, and 12 kDa. And, results of the analysis of S. sanguis receptor molecules using Western blot showed that there were three bands, each of which molecular weight was 130, 85, and 40 kDa. Conclusion: S. sanguis bacteria have specific receptor molecules for S. mutans bacteria with the molecular weight of 130, 85, and 40 kDa.

Dental caries is the most common bacterial disease of humans and occurs when oral bacteria produce acids, following their fermentation of dietary carbohydrates. This acid can then cause a localised demineralisation of the tooth surface. A group of seven species of bacteria, collectively known as the mutans streptococci, have been predominantly implicated in the onset of dental caries. In particular, Streptococcus mutans and Streptococcus sobrinus have been shown to be the main aetiological agents of this disease in humans. Most attempts to control the microbial component of caries target these bacteria. The past 50 years has provided considerable information about the pathogenesis of dental caries, the likely route and time of transmission of cariogenic bacteria to susceptible hosts and possible ways of either treating or controlling the onset of this disease. In regards to the latter, many techniques (such as the use of tooth brushes, mouth washes, dental floss and tooth paste) for the control of plaque build-up exist and the examples listed are generally part of a daily routine. However, these techniques need to be applied regularly, and as such only highly-motivated individuals generally experience improved oral health. Therefore, the search for more effective less labour-intensive approaches continues. One area of research is into the potential application of small ribosomally-synthesised antimicrobial peptides, known as bacteriocins. Bacteriocins generally inhibit closely-related species that occupy the same ecological niche. Their relatively-specific targeting, plus the fact that many are remarkably heat and chemically-stable molecules, makes them excellent candidates for possible anti-caries applications. Numerous bacteriocins produced by the lactic acid bacteria have now been identified. Most can be broadly categorised into one of four main classes, of which Class I, the lantibiotics and Class II, the small (<10 kDa) non-modified peptides, contain the most examples. Many screens for anti-mutans streptococcal (MS) bacteriocins have been carried out and it appears that the best source of anti-MS bacteriocins are the mutans streptococci themselves. Research in this laboratory has identified examples of anti-mutans streptococcal bacteriocins produced by both mutans streptococci and non-mutans streptococci. The present study investigated the anti-MS inhibitors produced by two streptococcal strains, S. mutans N and Streptococcus sanguis K11. During the course of this study a third strain, S. mutans UA159, was also studied for its bacteriocinogenic properties. Although S. sanguis K11 produces anti-mutans streptococcal inhibitory activity, this appears only effective against Streptococcus rattus. In addition however, the inhibitory activity of this strain is also directed against all tested strains of Streptococcus agalactiae and ca. 50% of Streptococcus pyogenes. In the present study a 5069 Da novel inhibitory agent (sanguicin K11) was characterised and shown responsible for this unusual inhibitory spectrum. Through reverse genetics the sanK11 locus was identified and shown to encode a Class II type bacteriocin, the first shown to be produced by S. sanguis. Following screens of additional S. sanguis, sanK11 was shown to be present only in strains producing the same type of inhibitory pattern (P-type) as strain K11. The cysteine residues at positions 7 and 38 of the sanguicin K11 propeptide were shown to form a disulphide bridge essential for sanguicin K11 inhibitory activity. S. mutans N and eight other S. mutans strains have been found to have what appears to be the same inhibitory spectrum, which includes members of the mutans streptococci and several other oral streptococcal species. One strain (UA140) of the eight has previously been shown to produce the lantibiotic mutacin I and the non-lantibiotic mutacin IV. S. mutans N was known to produce the non-lantibiotic mutacin N. The current study set out to investigate how two strains, apparently producing completely different bacteriocins could have the same inhibitory spectrum. Reverse genetics identified the mutacin N structural gene (mutN) and mutagenesis studies showed that this bacteriocin was responsible only for the inhibitory activity against mutans streptococci. Further sequencing around the mutN locus identified a second bacteriocin-like locus (mutO) adjacent to mutN. mutO was also identified to have anti-mutans streptococcal inhibitory activity and because of the close proximity of mutO and mutN and given the homology they share with other known two-peptide bacteriocins it seemed probable that mutacins O and N are components of a new member of this special class of bacteriocins (Class IIb, the two peptide bacteriocins) in which the optimal inhibitory activity is dependent on the co-operative activity of the two peptides. Further investigations of strain N examined the expression of mutacins O and N. During a search for a suitable heterologous non-mutacinogenic S. mutans strain to act as an expression host, the genome reference strain, S. mutans UA159 was given consideration. However, contrary to previous reports, this strain was found to exhibit bacteriocin-like inhibitory activity. During a follow-up investigation, strain UA159 was found to inhibit 84 strains representing 11 different species of bacteria, but no inhibition of mutans streptococci was detected. The locus (nlmAB) encoding the two-peptide bacteriocin mutacin IV was identified within the UA159 genome. Using genetic dissection of nlmA and nlmB, the contribution of each peptide was examined and it was found that only the NlmA* propeptide appears to be active, raising doubts as to whether mutacin IV is a bona fide two-peptide bacteriocin. Deletion of the entire nlmAB locus created a mutant strain that exhibited a loss of inhibitory activity against the same 64 strains as was found for the nlmA mutant. A BLASTP search for the consensus leader sequence that precedes the propeptide of Class II bacteriocins, identified ORFs encoding 9 more putative bacteriocin-like peptides. Further genetic dissection identified the SMU.1914c locus as being responsible for the inhibitory activity against a further 15 strains not already sensitive to mutacin IV. SMU.1914c was renamed mutacin V. However, it appears that another as yet unidentified mutacin(s) is also produced by strain UA159 given that three indicator strains still remained sensitive to a double mutant [UA[Delta](1914/NlmAB)] in which both the mutacin IV and putative mutacin V loci were inactivated. Export of Class II bacteriocins has been found to occur by either a SEC-dependent system or via a dedicated peptide ATP Binding Cassette (ABC) transporter. Three potential ABC transporter ORFs were identified in S. mutans UA159. Two (comA and cslA) had the characteristic accessory factor ORF (comB and cslB respectively) located adjacent to the main ABC transporter ORF, while the third ORF763 appeared to lack this. Mutagenesis of each of these five ORFS was carried out and confirmed cslAB to be the ABC transporter involved in the export of the competence stimulating factor, while the function of ORF763 could not be established in this study. Mutagenesis of either comA or comB resulted in a complete cessation of bacteriocin production by the respective mutant strains. Historically, comA and comB is the nomenclature used for loci encoding the exporter of the competence inducing factors in streptococci. In light of this new information, comA and comB were renamed nlmT and nlmE respectively, to account for the newly defined role of this ABC transporter. The present study investigated four bacteriocins two of which (sanguicin K11 and mutacin ON) appear to have some potential for application to anti-caries control, and the others (mutacins IV and V) being shown to be produced by the genome reference strain (UA159). All three mutacins were shown to be exported from their respective producer cells by the NlmTE ABC transporter, while sanguicin K11 is predicted to be exported by a peptide ABC transporter located adjacent to sanK11. Bacteriocins may yet provide a novel alternative for the treatment and control of dental caries. In their favour is that fact that they have relatively narrow defined inhibitory spectra and thus are unlikely to produce widespread changes to plaque ecosystems. Potential uses include as topical agents where bacteriocin preparations could be incorporated into dentrifices such as toothpastes or mouthwashes. Alternatively, streptococci producing anti-mutans streptococcal bacteriocins could be implanted into the oral cavity in strain replacement therapy strategies. There are pros and cons to each technique and the most effective anti-caries control appears more likely to result from "cocktail therapy" where bacteriocins are combined with a number of other anti-mutans streptococcal agents to achieve long-lasting protection against mutans streptococcus proliferation.

Oral Biology
M.S.
Objectives: Cardiovascular disease (CVD), including heart attack, angina, and stroke, is ranked as the number one cause of mortality world wide. High blood cholesterol is linked to CVD and is an important risk factor. Statins – cholesterol lowering drugs- are first choice drugs for reducing the chance of suffering a CVD event. In the USA alone, approximately 32 million individuals take statins. Although randomized control trials of statins have demonstrated their efficacy in preventing CVD, much less information has been reported on their unintended effects. Although not thought of traditionally as antimicrobials, statins have been shown to have antimicrobial effects in vitro. The statins belong to a family of drugs that lower cholesterol levels by inhibiting 3-hydroxy-3-methylglutaryl-CoA reductase, a rate limiting enzyme in the human mevalonate pathway of which cholesterol in the biosynthetic end product. The mevalonate pathway is an important cellular metabolic pathway present in many bacteria. Hence, the aim of this study was to assess the in vitro efficacy of statins against selected strains of oral streptococci, as determined by the minimum inhibitory concentration. A second related objective is to assess the in vitro effect of statins on single species biofilm formation , as determined by binding of the same streptococci to hydroxyapatite pegs. Methods: The effect of statins on S. mutans, S. sanguis, and S. salivarius was determined by finding the minimum inhibitory concentration (MIC) by broth dilution assays. Simvastatin, pravastatin atorvastatin, and rousuvastatin were used in this study. The minimum inhibitory concentration was considered to be the lowest concentration of statin that prevented bacterial growth, i.e. a clear test tube. Experiments were repeated twice for each bacterial species. The effect of simvastatin, atorvastatin, and pravastatin on the ability of S. mutans and S. sanguis to form single species biofilm was assayed using sterile microplates and the MBEC Biofilm Inoculator (Innovatech). Results: Two trials indicated that the MIC of simvastatin against the selected oral bacteria was determined to be 15.6 μg/ml for S. mutans and S. sanguis, and 7.8 μg/ml for S. salivarius. The MIC of rosuvastatin and atorvastatin was determined to be 100 μg/ml against all three streptococci, whereas the MIC of pravastatin was even higher (200 μg/ml) against all three streptococci. Likewise, two trials indicated that statins decreased single species biofilm formation by S. mutans and S. sanguis. For simvastatin, biofilm formation was decreased by concentrations eight fold below the MIC . The results were substantiated by spectrophotometric assay . For atorvastatin and pravastatin, biofilm formation was decreased by concentrations 3-4 fold below the MIC. Conclusions: These experiments demonstrate the in vitro antimicrobial effect of statins on S. mutans, S.sanguis, and S. salivarius. The data indicate that the statins inhibit growth of the test organisms with MIC’s ranging from 7.8-200 μg/ml. Simvastatin has in vitro efficacy against the specific strains of bacteria used in this study at concentrations slightly less than the observed MIC’s of 15.6-7.8 μg/ml . The MIC’s for atorvastatin, pravastatin, and rosuvastatin are much higher than simvastatin, in the range of 100-200 μg/ml . The effects of statins on biofilm parallels the effect on growth of the bacteria.
Temple University--Theses

Cell surfaces of aggregation, adherence or hydrophilic variants of Streptococcus sanguis were compared to cell surfaces of the parent strain with regard to their protein and antigenic constituents. Cell surface molecules were released by digestion with mutanolysin. Extraction with SDS-BME, urea, lithium chloride and boiling water did not solubilize any material which stained with silver nitrate in an SDS-polyacrylamide gel. The parent organism S. sanguis 12 which aggregates in saliva, adheres to saliva coated hydroxyapatite (S-HA) and is hydrophobic was found to possess a prominently staining 160,000 MW protein. This protein was almost completely absent from strain I2na, a hydrophobic non-aggregating variant, and was completely absent from the hydrophilic non-aggregating, non-adherent strain 12L. Trypsinization of strain 12 resulted in the coincident loss of the 160,000 MW protein and the ability to aggregate in saliva. Trypsin treatment reduced, but did not eliminate the hydrophobic character of the cells. Boiling destroyed the ability to aggregate but did not alter hydrophobicity. Cell wall digests of strain 12 contained a large number of proteins which were absent from strains 12na and 12L. Mutanolysin digests of the hydrophilic strains contained no material that was visible in a silver stained SDS-polyacrylamide gel. Electron microscopy of phosphotungstic acid stained cells showed a thick capsular material spread evenly over the cell surface of the parent strain 12. This layer was thinner around the cells of strain 12na and appeared patchy on hydrophilic strains. Electron microscopy of uranyl acetate stained cells revealed that strain 12 had short fibrillar structures evenly distributed over the cell surface, and long fibrils which were more concentrated at the end of the cell. The hydrophilic strain 12L lacked both types of fibrils. Crossed immunoelectrophoresis confirmed that the major cell surface antigens were located in the 160,000 MW region. Cell wall digests of strain 12 and 12na inhibited adherence of strain 12 to S-HA by 36% and 19% respectively. The digests of hydrophilic strain 12L were not inhibitory. The inhibitory activity was sensitive to heat and SDS.
Science, Faculty of
Microbiology and Immunology, Department of
Graduate

Streptococcus sanguis 12 adhesins mediating attachment to saliva-coated hydroxyapatite beads (S-HA) were isolated and characterized. Cell surface fibrils were released from this organism by a method of freeze-thawing followed by brief homogenization. Fibrils in the homogenate were precipitated by ultracentrifugation or ammonium sulphate precipitation. This precipitate was shown to contain fibrils by electron microscopy. Sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE) analysis of fibrils showed a single band which stained with Coomassie blue and periodate-Schiff. The molecule had a Mr in excess of 300,000. This protein has been given the name long-fibril protein (LFP). Antibody raised against the LFP reacted with long fibrils of S. sanguis 12. LFP was degraded by subtilisin, pronase, papain, and trypsin, but not by chymotrypsin and muramidases. Fibrils were hydrolyzed by subtilisin into discrete lower Mr protein bands which reacted with both anti-fibril and anti-LFP serum. F(ab')₂ prepared from anti-fibril IgG inhibited adhesion of S. sanguis 12 to pH modified S-HA, indicating that fibrils were acting as an adhesin mediating attachment via the neuraminidase-sensitive receptor on S-HA. Five recombinant clones expressing surface antigens of S. sanguis 12 were isolated by ligating a partial digest of S. sanguis 12 chromosomal DNA with the plasmid vector pUC 18, and transforming into Escherichia coli JM83. Recombinant clones were screened by a colony immunoassay with antisera raised against either S. sanguis 12 whole cells or with anti-fibril serum. Positive clones were then analyzed by SDS-PAGE, Western blotting and restriction endonuclease digestion of recombinant plasmids. One recombinant plasmid, pSA2 expressed two proteins of Mrs of 20,000 and 36,000. The 36,000-Mr protein has been designated as SsaB (S. sanguis adhesin B). Both proteins were purified to homogeneity by gel filtration and ion exchange chromatography. Anti-SsaB serum was used in an immunogold bead labelling experiment to demonstrate that this protein was present on the surfaces of S. sanguis 12 and in the non-saliva-aggregating variant 12na, but not on the non-adhering non-aggregating hydrophilic variant 12L. Western blot analysis with anti-SsaB and anti-20 kd sera showed that both SsaB and the 20 kd proteins were present in cell extracts of S. sanguis 12 and its variants. SsaB inhibited adhesion of S. sanguis 12na to S-HA, indicating that it was the adhesin which mediates the binding to the pH-sensitive receptor. SsaB was found to be present on all S. sanguis strains tested, but not on other oral streptococci. Chemical cross-linking studies of SsaB on S. sanguis 12 cell surface suggested that this protein may be present in a higher Mr complex. This study provides direct evidence that binding of S. sanguis 12 to S-HA involves at least two adhesin-receptor interactions. The adhesin mediating binding to the neuraminidase-sensitive receptor on S-HA involves the long fibrils and the adhesin binding to the acid labile receptor is a 36,000 Mr protein.
Science, Faculty of
Microbiology and Immunology, Department of
Graduate

Trabajo de Investigación Requisito para optar al Título de Cirujano Dentista
Introducción: Streptococcus sanguinis (S. sanguinis) es un colonizador primario de la biopelícula dental asociada a salud. Esta bacteria produce peróxido de hidrógeno (H2O2), un sub-producto del crecimiento y que es bacteriostático para otros streptococci orales, como Streptococcus mutans (S. mutans), quien, bajo condiciones determinadas de pH y disponibilidad de carbohidratos fermentables, se relaciona con el inicio y progresión de la caries dental. En este contexto, actualmente se propone una relación sinérgica entre S. mutans y Candida albicans (C. albicans), levadura comensal de la cavidad oral capaz de causar diversas patologías en humanos. El efecto de S. sanguinis, mediante la producción de (H²O²), en C. albicans no ha sido completamente estudiado. Según lo mencionado anteriormente, el objetivo de este estudio es determinar preliminarmente si existe modulación del crecimiento de C. albicans, en co-cultivo con S. sanguinis. Material y Métodos: Se utilizó S. sanguinis SK36, S. mutans ATCC 25175, C. albicans ATCC 90029 y un aislado clínico de C. albicans (P1-1) (proveniente de un niño con caries activas). Se realizaron ensayos de competencia en medio líquido y sólido de S. sanguinis o S. mutans con C. albicans (cepa de referencia o aislado clínico), se determinó pH y células viables para cada pareja en co-cultivo líquido. Inhibición del crecimiento en medio sólido fue evaluada según presencia de halo inhibitorio próximo a alguno de los microorganismos. Ensayos fueron incubados en microaerofilia a 37 ºC durante 48 h con agitación. Además, se realizó un test de concentración inhibitoria mínima (CIM) de (H²O²) para ambas cepas de C. albicans y también se determinó la cantidad de (H²O²) producida por S. sanguinis, de acuerdo a una curva estándar previamente diseñada. Los datos fueron analizados de manera descriptiva, comparando medianas entre distintos grupos y dentro de un mismo grupo. Resultados: En medio sólido, C. albicans produjo halo inhibitorio sobre S. sanguinis. En medio líquido, S. sanguinis y C. albicans (ATCC y P1-1) aumentaron su crecimiento en co-cultivo, respecto de su crecimiento aislado. Además, generaron siempre una alcalinización del medio, respecto al pH inicial. A 0,1 mM de (H²O²) la sobrevivencia de ambas cepas de C. albicans se redujo en un 70%, definiendo esta concentración como la CIM. La cantidad estimada de (H²O²) producida por S. sanguinis fue de 0,059 µM en todas las etapas de crecimiento. Conclusiones: De acuerdo a los resultados obtenidos y a las limitaciones del estudio, se puede concluir que S. sanguinis no inhibe el crecimiento de C. albicans. Asimismo, ambos podrían contribuir en mantener el pH del microambiente en niveles compatibles con salud oral. El co-cultivo de C. albicans con S. mutans podría beneficiar el crecimiento de la bacteria, en desmedro de la levadura. No obstante, cuando la levadura proviene de una biopelícula cariogénica, su relación con la bacteria podría tornarse más sinérgica. Entonces, el rol de C. albicans dentro del proceso de caries podría depender de la condición que presenta el microambiente, previo a la presencia de la levadura. El (H²O²) podría influir negativamente en el crecimiento de C. albicans, sin embargo, este efecto estaría supeditado a su concentración en el medio.
Adscrito a Proyecto U-inicia Difarp 40/13, VID, U. de Chile.

The target was evaluate the “in vitro” antibacterial effect about five peruvian propolis on strains of Streptococcus mutans (ATCC 25175) and Streptococcus sanguinis (ATCC 10556), Having an experimental study design “in vitro” made in laboratorie of Microbiology of the Peruvian University of Applied Sciences. Materials and Methods: Sample size were about ten holes for each of the five extracts of propolis, either for Streptococcus mutans and Streptococcus sanguinis individualy. The antibacterial effect was developed with the technical “Agar overlay interference test”, which is used 200ml of Agar BHI homogenized with bacteria indispensably (a bottle for bacteria). This agar is distributed in the plates, once solidified the holes are made with 150μL of different kinds of propolis and the control group called Clorhexidine 0.12%. Completed this process is placed in the anaerobiosis chamber on 37º C, for 72 hours. Finally, the measurement of the inhibitory halo is made. Results: The methanolic extract of propolis of Oxapampa-Perú present inhibition halos in larger averaging of 33.15 + 3.26 mm against strains of Streptococcus mutans (ATCC 25175) and Streptococcus sanguinis (ATCC 10556), their average was about 23.23 + 0.82mm. In case of 4 extracts of commercial, just 3 of them (tincture of propolis Farmagel, Madre Nature y Kaita®), had bacterian activity in front of the studies strains. In all cases the antibacterian activity is less than positive control. Conclusions: The methanolic extract of propolis of Oxapampa-Peru, made in the laboratory has better antibacterian activity than commercial extracts against strains of Streptococcus mutans (ATTC 25175) and Streptococcus sanguinis (ATCC 10556). About the four commercial propolis evaluated on this study, propolis tincture Farmagel, Kaita®, Madre Natura and Max propolis tincture, only three of this have antibacterial activity against strains of de Streptococcus mutants (ATCC 25175) and Streptococcus sanguinis (ATCC 10556).
El objetivo fue evaluar in vitro el efecto antibacteriano de cinco propóleos peruanos sobre cepas de Streptococcus mutans (ATCC 25175) y Streptococcus sanguinis (ATCC 10556) teniendo un diseño de estudio experimental in vitro, realizado en el laboratorio de Microbiología de la Universidad Peruana de Ciencias Aplicadas. Materiales y métodos: se comparó el efecto antibacteriano de cuatro marcas comerciales de propóleo Tintura de propóleo Farmagel, Tintura de propóleo Max, Madre Natura, Kaita® y un extracto metanólico de propóleo de Oxapampa, el cual se elaboró en el laboratorio de Bioquímica de la UPC, como control (+) la clorhexidina al 0.12%. Para este estudio se utilizó 10 pocillos por cada extracto de propóleo, para el Streptococcus mutans y para el Streptococcus sanguinis individualmente. Se desarrolló con la técnica “Agar overlay interference test”, para lo cual se utilizó 200ml de Agar BHI homogenizado con las bacterias de manera independiente (un frasco por bacteria). Se distribuyó este agar en las placas, una vez solidificado se realizaron los pocillos con 150μL de los distintos tipos de propóleo y para el grupo control, se utilizó clorhexidina al 0.12%. Terminado este proceso se colocó en la cámara de anaerobiosis a 37°C, durante 72 horas. Por último, se realizó la medición del halo inhibitorio con una regla Vernier. Resultados: El extracto metanólico de propóleo de Oxapampa presentó halos de inhibición de mayor tamaño con una media de 33.15 + 3.26 mm frente a las cepas de Streptococcus mutans (ATCC 25175), para el Streptococcus sanguinis (ATCC 10556) su media fue de 23.23 + 0.82 mm. En el caso de los 4 extractos de propóleo comerciales, sólo 3 de ellos (Tintura de propóleo Farmagel, Madre Natura y Kaita®), tuvieron actividad antibacteriana frente a las cepas estudiadas, en todos los casos la actividad antibacteriana es menor que el control (+). Conclusiones: El extracto metanólico de propóleo de Oxapampa elaborado en el laboratorio tiene mayor actividad antibacteriana que los extractos comerciales frente a las cepas Streptococcus mutans (ATCC 25175) y Streptococcus sanguinis (ATCC 10556). De los 4 propóleos comerciales evaluados en el estudio, Tintura de propóleo Farmagel, Kaita®, Madre Natura y Tintura de propóleo Max, sólo tres de ellos tiene actividad antibacteriana frente a las cepas de Streptococcus mutans (ATCC 25175) y Streptococcus sanguinis (ATCC 10556).
The target was evaluate the “in vitro” antibacterial effect about five peruvian propolis on strains of Streptococcus mutans (ATCC 25175) and Streptococcus sanguinis (ATCC 10556), Having an experimental study design “in vitro” made in laboratorie of Microbiology of the Peruvian University of Applied Sciences. Materials and Methods: Sample size were about ten holes for each of the five extracts of propolis, either for Streptococcus mutans and Streptococcus sanguinis individualy. The antibacterial effect was developed with the technical “Agar overlay interference test”, which is used 200ml of Agar BHI homogenized with bacteria indispensably (a bottle for bacteria). This agar is distributed in the plates, once solidified the holes are made with 150μL of different kinds of propolis and the control group called Clorhexidine 0.12%. Completed this process is placed in the anaerobiosis chamber on 37º C, for 72 hours. Finally, the measurement of the inhibitory halo is made. Results: The methanolic extract of propolis of Oxapampa-Perú present inhibition halos in larger averaging of 33.15 + 3.26 mm against strains of Streptococcus mutans (ATCC 25175) and Streptococcus sanguinis (ATCC 10556), their average was about 23.23 + 0.82mm. In case of 4 extracts of commercial, just 3 of them (tincture of propolis Farmagel, Madre Nature y Kaita® ), had bacterian activity in front of the studies strains. In all cases the antibacterian activity is less than positive control. Conclusions: The methanolic extract of propolis of Oxapampa-Peru, made in the laboratory has better antibacterian activity than commercial extracts against strains of Streptococcus mutans (ATTC 25175) and Streptococcus sanguinis (ATCC 10556). About the four commercial propolis evaluated on this study, propolis tincture Farmagel, Kaita® , Madre Natura and Max propolis tincture, only three of this have antibacterial activity against strains of de Streptococcus mutants (ATCC 25175) and Streptococcus sanguinis (ATCC 10556).

Objective: The aim of this study was to evaluate the antibacterial effect of Camellia sinensis (green tea) on Streptococcus mutans (ATCC 25175) and Streptococcus sanguinis (ATCC10556). Materials and Methods: The methanolic extract of green tea (commercial and bulk) was examined on Streptococcus mutans (ATCC 25175) and Streptococcus sanguinis (ATCC10556), using the well assay method. A total of 24 plates for the first extract (Commercial) and the same amount for the extract No. 2 (Bulk) were used and were divided into groups of 12 disks for each bacterium, with a total of 4 disks per group. In addition, each plate contained 3 disks embedded with tea and 1 disc with 0.12% chlorhexidine as a control group. Results: It was found antibacterial effect in both methanolic extracts of green tea. No statistically significant differences when comparing the natural green tea with the other extract, in every single microorganism. A p value of 0.18 and 0.63 respectively were obtained. The methanol extract of the commercial green tea had better antibacterial effect than the second extract with an average of 19.72 mm, for the second extract of green tea was 18.1 mm against Streptococcus mutans, whereas for Streptococcus sanguinis was 17.94mm and 16.46 mm respectively. The minimum inhibitory concentration (MIC) for the commercial and bulk extract was 0.08 gr/ml against Streptococcus mutans and 0.08 gr/ml and 0.25 gr/ml against the strains of Streptococcus sanguinis respectively. Conclusions: Both methanolics extracts, commercial and bulk have anti Streptococcus mutans (ATCC 25175) and Streptococcus sanguinis (ATCC10556) activity in vitro. The activity of commercial tea had better effects than the bulk methanolic extract.
Objetivo: Evaluar in vitro el efecto antibacteriano de la Camellia sinensis (té verde) frente al Streptococcus mutans (ATCC 25175) y al Streptococcus sanguinis (ATCC10556). Materiales y métodos: Se probaron dos extractos de té verde, uno comercial y otro a granel. Se utilizaron 24 discos para el primer extracto (Comercial) y la misma cantidad para el segundo extracto metanólico (Granel), se dividieron en grupos de 12 discos para cada bacteria, con un total de 4 placas petri por cada uno. Además, cada placa contenía 3 discos embebidos de té y 1 disco con Clorhexidina al 0.12% como grupo control. Estas muestras fueron analizadas con el método de difusión en agar con discos y los halos de inhibición se midieron a las 72 horas. Resultados: Se encontró efecto antibacteriano para ambos extractos probados. El promedio del halo de inhibición para el extracto de té verde comercial fue de 19.72 mm y para el extracto de té verde a granel fue de 18.1 mm frente al Streptococcus mutans, mientras que para el Streptococcus sanguinis la media obtenida fue de 17.94 mm y 16.46 mm respectivamente. Con respecto a la Concentración mínima inhibitoria (CMI), para el caso de Streptococcus mutans se determinó una CMI de 0.08 gr/ml para el extracto comercial y al extracto a granel. Mientras que para el caso de Streptococcus sanguinis la CMI fue de 0.08 gr/ml para el extracto comercial y de 0.25 gr/ml para el extracto a granel. Conclusiones: Ambos extractos metanólicos de té verde presentaron efecto antibacteriano contra las cepas del Streptococcus mutans (ATCC 25175) y Streptococcus sanguinis (ATCC10556). El té verde comercial fue el que presentó mayor efecto antibacteriano que el extracto a granel.

In bacterial endocarditis the causing microorganisms are located in a fibrin-platelet matrix, making them less accessible to host-defence mechanisms and antibiotic therapy. Trombolytic treatment could break down the fibrin of these endocardial vegetations and thus eliminate the focus of infection. This approach was studied in vitroand in vivo using recombinant t-PA (rt-PA,Wellcome Biotech) having a fibrinolytic activity comparable with melanoma t-PA. The following results were obtained.1.Incubation of Streptococcus sanguis infected plasma clots in the presence of t-PA resulted in lysis of the clots as evidenced by a significant decrease in the weight of the clots and by an increase in the number of streptococci in the medium.No effect of t-PA was found on the antimicrobial action of penicillin G (PenG)onthe streptococci in the non-lysed part ofthe clots.2. Vegetations isolated from the heart of rabbits with a S. sanguis endocarditis,incubated in medium with t-PA were also lysed. This resulted in a rise in the mediumof both the number of bacteria and the concentration of fibrin degradation products.3.Treatment of rabbits with a S. sanguis endocarditis using a combination of rt-PA, given as bolus injections at one hour intervals (4x0.5 or 4x1 mg per kg/day), andPenG decreased the weight of the endocardial vegetations significantly compared toa control group treated with PenGonly (43.3 and 81.8 mg respectively). No additional decrease in weight was obtained with repeated administration of t-PA at daily intervals up to 2 days. The significant decrease of the number of streptococci per gram of vegetation as a result of the treatmentwith PenG was not influenced by t-PA. Treatment with 4x1 mg t-PA per kg caused a small decrease (about 30%) in the plasma concentration of plasminogen, fibrinogen and aα2~antiplasmin.However, no bleeding complications were observed.In conclusion rt-PA can influence the treatment of bacterial endocarditis in rabbits by decreasing the size of the vegetations but not by influencing antimicrobial action on the bacteria in the non-lysed part of the vegetation.