The oral microbiota: a literature review for updating profesional s in dentistry-Part II / La microbiota oral: una revisión de literatura para la actualización de profesionales en odontología-Parte II

ABSTRACT: In the first part of this literature review, published in October 2019 in this journal, we summarized the conceptual background of the oral microbiota, and the main methods used in microbiology to characterize oral organisms. We also presented the most studied bacteria species in the oral microbiota. In this second part, we will discuss the evidence regarding the biological plausibility linking the oral microbiota dysbiosis and systemic diseases, as well as the main factors and mechanisms suspected in this association.

RESUMEN: En la primera parte de esta revisión de literatura, publicada en esta revista en octubre de 2019, se resumieron los antecedentes conceptuales de la microbiota oral y describieron los principales métodos utilizados en microbiología para caracterizar los microorganismos orales. Asimismo, se presentaron las especies bacterianas mejor estudiadas de la microbiota oral. En esta segunda parte, se explorará la plausibilidad biológica que vincularía la disbiosis de la microbiota oral y las enfermedades sistémicas, así como las características que podrían influenciar la composición de la microbiota oral.

Optimization of L-asparaginase production from endophytic Fusarium proliferatum using OFAT and RSM and its cytotoxic evaluation.

L-asparaginase from endophytic Fusarium proliferatum (isolate CCH, GenBank accession no. MK685139) isolated from the medicinal plant Cymbopogon citratus (Lemon grass), was optimized for its L-asparaginase production and its subsequent cytotoxicity towards Jurkat E6 cell line. The following factors were optimized; carbon source and concentration, nitrogen source and concentration, incubation period, temperature, pH and agitation rate. Optimization of L-asparaginase production was performed using One-Factor-At-A-Time (OFAT) and Response surface methodology (RSM) model. The cytotoxicity of the crude enzyme from isolate CCH was tested on leukemic Jurkat E6 cell line. The optimization exercise revealed that glucose concentration, nitrogen source, L-asparagine concentration and temperature influenced the L-asparaginase production of CCH. The optimum condition suggested using OFAT and RSM results were consistent. As such, the recommended conditions were 0.20% of glucose, 0.99% of L-asparagine and 5.34 days incubation at 30.50 °C. The L-asparaginase production of CCH increased from 16.75 ± 0.76 IU/mL to 22.42 ± 0.20 IU/mL after optimization. The cytotoxicity of the crude enzyme on leukemic Jurkat cell line recorded IC50 value at 33.89 ± 2.63% v/v. To conclude, the enzyme extract produced from Fusarium proliferatum under optimized conditions is a potential alternative resource for L-asparaginase.

Emerging technologies and infection models in cellular microbiology.

The field of cellular microbiology, rooted in the co-evolution of microbes and their hosts, studies intracellular pathogens and their manipulation of host cell machinery. In this review, we highlight emerging technologies and infection models that recently promoted opportunities in cellular microbiology. We overview the explosion of microscopy techniques and how they reveal unprecedented detail at the host-pathogen interface. We discuss the incorporation of robotics and artificial intelligence to image-based screening modalities, biochemical mapping approaches, as well as dual RNA-sequencing techniques. Finally, we describe chips, organoids and animal models used to dissect biophysical and in vivo aspects of the infection process. As our knowledge of the infected cell improves, cellular microbiology holds great promise for development of anti-infective strategies with translational applications in human health.

A protein-free chemically defined medium for the cultivation of various micro-organisms with food safety significance.

AIMS: To develop a broadly applicable medium free of proteins with well-defined and reproducible chemical composition for the cultivation of various micro-organisms with food safety significance. METHODS AND RESULTS: The defined medium was designed as a buffered minimal salt medium supplemented with amino acids, vitamins, trace metals and other nutrients. Various strains commonly used for food safety research were selected to test the new defined medium. We investigated single growth factors needed by different strains and the growth performance of each strain cultivated in the defined medium. Results showed that the tested strains initially grew slower in the defined medium compared to tryptic soy broth, but after an overnight incubation cultures from the defined medium reached adequately high cell densities. CONCLUSIONS: The newly designed defined medium can be widely applied in food safety studies that require media with well-defined chemical constituents. SIGNIFICANCE AND IMPACT OF THE STUDY: Defined media are important in studies of microbial metabolites and physiological properties. A defined medium capable of cultivating different strains simultaneously is needed in the food safety area. The new defined medium has broader applications in comparing different strains directly and provides more reproducible results.

Análise Microbiológica do Colostro em Lactantes de um Município de Minas Gerais/Brasil / Microbiological Analysis of Colostrum in Lactating Women in a Municipality of Minas Gerais/Brazil

Introdução: A cesárea é realizada em condições maternas e/ou fetais que impeçam o nascimento via vaginal. Devido ao risco de complicações infecciosas, o procedimento é precedido de antibioticoprofilaxia, o que pode provocar a seleção de cepas multirresistentes e alterar a flora nativa do indivíduo. O colostro é um fator determinante para a colonização do trato digestivo por ser fonte probiótica, além de apresentar papel importante na modulação do sistema imunológico e desenvolvimento do neonato. Objetivo: Este estudo visa avaliar possíveis interferências da antibioticoprofilaxia realizada previamente à cesárea na flora materna. Métodos: Selecionou-se 140 lactantes após aplicação dos critérios de exclusão, divididas em grupos estudo (realizaram parto cesáreo com antibioticoprofilaxia) e controle (realizaram parto vaginal sem antibioticoprofilaxia) para coleta das amostras ­ colostro e esfregaço areolar ­ com intuito de realizar a análise microbiológica das mesmas no Laboratório de Microbiologia da Faculdade de Medicina de Barbacena. Resultados: 94 lactantes pertencem ao grupo estudo e 46 ao controle. O microrganismo mais prevalente em todas as amostras foi a Candida sp. Ao se discriminar os grupos, a mesma também apresentou maior prevalência, seguida de Enterococcus sp. Em relação à detecção de Staphylococcus aureus pelo esfregaço mamilar, ele foi encontrado em 24 amostras do grupo controle e em 34 do grupo estudo. Na análise comparativa da prevalência de microrganismos entre os grupos, não se observou diferença estatisticamente relevante. Conclusão: A antibioticoprofilaxia peri-operatória mostrou-se segura em não alterar a composição da flora materna. Entretanto, mais estudos sobre o tema devem ser realizados.

Introduction: The C-section is performed under maternal and / or fetal conditions that prevent vaginal birth. Because of the infectious complications, the procedure is preceded by antibiotic prophylaxis, which can cause the selection of multidrug-resistant strains and shift the individual's native flora. Colostrum is a determining factor for colonization of the digestive tract being a probiotic source, along with playing an important role in the modulation of the immune system and development of the newborn. Objective: This study aims to assess possible interferences of antibiotic prophylaxis performed prior to cesarean section on maternal flora. Methods: 140 lactating women were selected after applying the exclusion criteria, divided into study groups (94 lactating women who underwent cesarean delivery with antibiotic prophylaxis) and control groups (46 lactating women who underwent vaginal delivery without antibiotic prophylaxis) for sample collection - colostrum and areolar swab - therefore perform the microbiological analysis at the Laboratório de Microbiologia da Faculdade de Medicina de Barbacena. Results: The most prevalent microorganism in all samples was Candida sp. Discriminating the groups, it also had the highest prevalence, followed by Enterococcus sp. Regarding the detection of Staphylococcus aureus by the areolar swab, it was found in 24 samples from the control group and 34 from the study group. In the comparative analysis of prevalence of microorganisms, between the groups, there was no statistically significant difference. Conclusion: Perioperative antibiotic prophylaxis proved to be safe not changing the composition of the maternal flora. However, further studies on the subject should be carried out.

Decolorization and biodegradation of melanoidin contained in beet molasses by an anamorphic strain of Bjerkandera adusta CCBAS930 and its mutants.

We used a ligninolytic strain of the white-rot fungus B. adusta CCBAS 930 and its mutants with modified ligninolytic activity to assess their potential to remove of molasses. The analyzed strains have been shown to be able to decolorize 1% or 2% molasses solutions containing brown-colored toxic melanoidins. It was found that the decolorization process was determined by the transition to the stage of production of sporulating aerial mycelium (liquid and agar cultures) coupled with an increase in peroxidase activity, which was accompanied by a decrease in the level of melanoidin, free radicals, and phenolic compounds. Four different peroxidase activities were detected in post-culture liquids, i.e. horseradish-like (HRP-like), manganese-dependent (MnP), lignin (LiP), and versatile (VP) peroxidase activities. The HRP-like peroxidase was characterized by the highest activity. The efficiency of removal of melanoidins from a 1% molasses solution by the parental strain and the mutants was dependent on the culture method. The highest efficiency was noted in immobilized cultures (threefold higher than in the mycelium-free cultures), which was accompanied by stimulation of HRP-like peroxidase activity. Mutant 930-5 was found to be the most effective in the decolorization and decomposition of melanoidin. The HRP-like activity in the immobilized cultures of B. adusta 930-5 was 640-fold higher than in the mycelium-free cultures of the fungus. Moreover, decolorization and biodegradation of melanoidin by B. adusta CCBAS 930 and 930-5 was coupled with detoxification.

In vitro resynthesis of lichenization reveals the genetic background of symbiosis-specific fungal-algal interaction in Usnea hakonensis.

BACKGROUND: Symbiosis is central to ecosystems and has been an important driving force of the diversity of life. Close and long-term interactions are known to develop cooperative molecular mechanisms between the symbiotic partners and have often given them new functions as symbiotic entities. In lichen symbiosis, mutualistic relationships between lichen-forming fungi and algae and/or cyanobacteria produce unique features that make lichens adaptive to a wide range of environments. Although the morphological, physiological, and ecological uniqueness of lichens has been described for more than a century, the genetic mechanisms underlying this symbiosis are still poorly known. RESULTS: This study investigated the fungal-algal interaction specific to the lichen symbiosis using Usnea hakonensis as a model system. The whole genome of U. hakonensis, the fungal partner, was sequenced by using a culture isolated from a natural lichen thallus. Isolated cultures of the fungal and the algal partners were co-cultured in vitro for 3 months, and thalli were successfully resynthesized as visible protrusions. Transcriptomes of resynthesized and natural thalli (symbiotic states) were compared to that of isolated cultures (non-symbiotic state). Sets of fungal and algal genes up-regulated in both symbiotic states were identified as symbiosis-related genes. CONCLUSION: From predicted functions of these genes, we identified genetic association with two key features fundamental to the symbiotic lifestyle in lichens. The first is establishment of a fungal symbiotic interface: (a) modification of cell walls at fungal-algal contact sites; and (b) production of a hydrophobic layer that ensheaths fungal and algal cells;. The second is symbiosis-specific nutrient flow: (a) the algal supply of photosynthetic product to the fungus; and (b) the fungal supply of phosphorous and nitrogen compounds to the alga. Since both features are widespread among lichens, our result may indicate important facets of the genetic basis of the lichen symbiosis.

Toward High-Throughput Fungal Electroculturomics and New Omics Methodologies in 21st-Century Microbiology and Ecology.

Modern microbiology and drug development are in a watershed moment with the advent of electroceuticals. In addition to genomics, electrical impulses in an organism are believed to contribute to tissue and cellular plasticity. Hence, electroceuticals or bioelectronics offers the promise to identify innovative approaches to treat human diseases. However, applications toward electromicrobiology are still limited and rare, despite the high potential to innovate the fields of both microbiology and therapeutics. For example, electric modalities for manipulating microbial growth are highly sustainable; can be combined with biopharmaceuticals, probiotics, and pharmacobiotics; and, thus, are well poised for use in medicine, public health, and ecology and diverse industries. We report here the introduction of a new research framework and technology platform for electroculturomics, by coupling standard solid-state mycological cultures with conductive treatment using a conformité Européene (CE-)-certified medical ionophoresis device. We share our experience with a diverse range of fungi that have been treated with the electroculturomics approach reported herein. We suggest that this line of inquiry can be extended to electrotranscriptomics and electrometabolomics by deploying electroculturomics in tandem with multi-omics approaches in the future. This article makes a specific contribution to fungal microbiology, and a broader contribution to advance the theory and practice of the field of electroculturomics emerging in 21st-century microbiology and ecology research.

Red Blood Cell Folate Likely Overestimated in Australian National Survey: Implications for Neural Tube Defect Risk.

In 2009, the Australian government mandated the addition of folic acid to bread flour to reduce the incidence of neural tube defects (NTD)-affected pregnancies. In 2011-2012, the Australian Health Measures Survey (AHMS) reported a mean red blood cell (RBC) folate in women of reproductive age (16-44 y) of 1647 nmol/L. Over 99% of women had an RBC folate ≥ 906 nmol/L, a concentration consistent with a very low risk of NTDs if a woman became pregnant. However, RBC folate was measured using an immunoassay, which is not a recommended method due to questionable accuracy. The microbiological assay is the preferred method for RBC folate measurement. To determine whether the immunoassay method may have led to spurious conclusions about the folate status of Australian women, we collected fasting blood samples from 74 healthy non-pregnant, non-lactating women (18-44 y) and measured RBC folate using both the immunoassay and microbiological methods. Mean RBC folate (95% confidence interval) concentration measured with the immunoassay method was 1735 (1666, 1804) nmol/L compared with 942 (887, 1012) nmol/L using the microbiological method. No woman had an RBC folate < 906 nmol/L using the immunoassay method, whereas 46% of women had an RBC folate < 906 nmol/L using the microbiological method. The NTD risk was estimated to be 0.06% using the immunoassay method and 0.14% using the microbiological method. RBC folate using AHMS survey may have underestimated NTD risk in Australian women.

A review on antimicrobial botanicals, phytochemicals and natural resistance modifying agents from Apocynaceae family: Possible therapeutic approaches against multidrug resistance in pathogenic microorganisms.

Accelerated emergence of drug- resistant pathogenic microbes, their unbeatable virulence and a gradual loss of efficacy of currently used antimicrobial agents over the last decade, have expanded the scope of herbal medicine to combat this emerging challenge to have a wide spectrum of activity to develop effective medicines with lesser untoward side effects. Plant-based natural products should be of utmost interest to today's pharmaceutical industries since they are a primary source of new chemical entities directed at new drug targets. Apocynaceae or 'Dogbane' family has attained a global reputation as a source of some life-saving plant-derived products and novel compounds. Members of this family have also been extensively investigated against several nosocomial pathogenic microbes through in vitro and in vivo experimental settings. Several plant-derived components obtained from members of this family have also exhibited remarkable microbial growth inhibitory properties. Popular and widely accepted international databases such as PubMed, Science Direct, ResearchGate, Scopus, Google Scholar, JSTOR and more were searched using the various search strings such as Apocynaceae, antimicrobials, multidrug resistance, resistance modifying agents and pathogenic microorganisms were used in various combinations to retrieve several citations related to the topic. The current review encompasses recent developments in experimental studies and phytochemical analyses which correlates with antimicrobial efficacy of selected Apocynaceous plants along with synergistic mechanism and structural details. The present review recognizes and leverages the importance of Apocynaceae plants, which could be of significant interest in the development of more effective and less toxic antimicrobial drugs which may surmount multidrug resistance. Three different paradigm models harnessing clinical antimicrobial resistance (AMR) including the plant family Apocynaceae, Gram-positive and Gram-negative bacterial species have been broadly discussed in this review. In a nutshell, the present review represents a comprehensive account on the antimicrobials and resistance modifying agents obtained from the members of the plant family Apocynaceae and derived phytochemicals. It also gives an insight into the underlying mode of action of these phytochemicals against an array of pathogenic bacteria, their mechanism of antibiosis, plant parts from which the phytochemicals were isolated or the extracts was prepared with a critical discussion on the botanically-derived antibiotics as a template for antimicrobial drug development.

Blind Spots of Traditional Microbiological Tests for Severe Community-Acquired Pneumonia in Adults and Availability of Nonculture Techniques: A Nationwide Survey of Physicians in China.

BACKGROUND: In China, no national survey has been conducted to evaluate physicians' attitudes and compliance with guidelines in the management of adult patients with community-acquired pneumonia (CAP). Therefore, this study aimed to evaluate physicians' awareness of the use of microbiological tests in the management of severe CAP (SCAP) and to investigate the availability of nonculture tests in China. METHODS: A nationwide electronic questionnaire survey was conducted among Chinese physicians between March and July 2018, which assessed their viewpoints concerning the issues in the management of SCAP. RESULTS: A total of 6333 physicians completed this survey, evenly covering all career stages. Among these, 3208 (50.6%) and 1936 (30.6%) had blind spots in the application of blood and sputum cultures in the management of SCAP, respectively. Nonteaching hospital, nonrespirologists, and junior career stage were independently associated with misunderstandings. Regarding nonculture methods, 52.7% of the facilities had no access to polymerase chain reaction-based pathogen detection tests. The accessibility of urinary antigen tests for Streptococcus pneumoniae (42.5%) and Legionella pneumophila (38.5%) was also low. The main barriers were inland and remote region, lower hospital level, and nonteaching hospital. CONCLUSIONS: Insufficient use of sputum and blood cultures, together with low accessibility of major nonculture techniques, were noticeable barriers to achieving microbiological diagnosis of SCAP in China. To help curb the overuse of broad-spectrum antibiotics, further measures should be taken to raise awareness among nonspecialists and promote rapid nonculture tests, especially in nonteaching hospitals and developing regions.

Major challenges and perspectives in the diagnostics and treatment of dermatophyte infections.

Dermatophytes are the aetiological factors of a majority of superficial fungal infections. What distinguishes them from other pathogenic filamentous fungi is their unique ability to degrade keratin. The remarkable ability of this group of fungi to survive in different ecosystems results from their morphological and ecological diversity as well as high adaptability to changing environmental conditions. Paradoxically, despite the progress in medicine, the prevalence of dermatophyte infections is increasing from year to year. At the beginning of the third millennium, practical diagnostic and therapeutic options are still very limited. This review focuses on understanding the major problems in this aspect of dermatophyte infections and indicates future strategies and perspectives for novel approaches to identification and drugs for elimination of dermatophytes. Particular importance is placed on development of a strategy for a diagnostic pathway and implementation of rapid and reliable diagnostics methods designed by international teams. Furthermore, among compounds that currently arouse great interest, representatives of terpenoids, alkaloids, saponins, flavonoids and essential oils deserve attention. Many of these compounds are undergoing clinical trials as potential antifungal agents, and future research should focus on attempts at determination of the applicability of tested substances. Finally, the advantages and disadvantages in implementation of new diagnostic paths and medicinal substances for routine use are indicated.

Characterization of γ-aminobutyric acid (GABA)-producing Saccharomyces cerevisiae and coculture with Lactobacillus plantarum for mulberry beverage brewing.

One elite γ-aminobutyric acid (GABA) producing strain of Saccharomyces cerevisiae SC125 was isolated and identified from Chinese traditional paocai. S. cerevisiae SC125 and Lactobacillus plantarum BC114 were used as cooperative species to ferment mulberry (Morus alba L.) and produce a novel beverage enriched with GABA. The GABA, organic acids and volatile compounds in different fermentation stages were determined by high-performance liquid chromatography (HPLC) and headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS). It was noted that coculture changed the profiles of flavor compounds in mulberry beverage. The tartaric and succinic acid contents increased to 1.34 g/L and 0.39 g/L, respectively. Lactic, malic, citric, and oxalic acid levels ranged between 0.92 and 2.56 g/L, and ethanol and glycerol were produced at 2.66 g/L and 1.81 g/L, respectively. More volatile compounds were detected in the coculture with significantly enhanced concentrations of fruity esters including ethyl caproate, ethyl propionate, butyl acetate, ethyl butyrate, ethyl caprylate and ethyl caprate, and alcohols of phenylethyl alcohol, 1-pentanol and 2-amino-1,3-propanediol. Also, a yield of 2.42 g/L GABA was achieved in the coculture. In conclusion, S. cerevisiae SC125 and L. plantarum BC114 coculture promotes the production of flavor compounds and GABA in mulberry beverage brewing.

Revealing nutritional requirements of MICP-relevant Sporosarcina pasteurii DSM33 for growth improvement in chemically defined and complex media.

Microbial induced calcite precipitation (MICP) based on ureolysis has a high potential for many applications, e.g. restoration of construction materials. The gram-positive bacterium Sporosarcina pasteurii is the most commonly used microorganism for MICP due to its high ureolytic activity. However, Sporosarcina pasteurii is so far cultivated almost exclusively in complex media, which only results in moderate biomass concentrations at the best. Cultivation of Sporosarcina pasteurii must be strongly improved in order to make technological application of MICP economically feasible. The growth of Sporosarcina pasteurii DSM 33 was boosted by detecting auxotrophic deficiencies (L-methionine, L-cysteine, thiamine, nicotinic acid), nutritional requirements (phosphate, trace elements) and useful carbon sources (glucose, maltose, lactose, fructose, sucrose, acetate, L-proline, L-alanine). These were determined by microplate cultivations with online monitoring of biomass in a chemically defined medium and systematically omitting or substituting medium components. Persisting growth limitations were also detected, allowing further improvement of the chemically defined medium by the addition of glutamate group amino acids. Common complex media based on peptone and yeast extract were supplemented based on these findings. Optical density at the end of each cultivation of the improved peptone and yeast extract media roughly increased fivefold respectively. A maximum OD600 of 26.6 ± 0.7 (CDW: 17.1 ± 0.5 g/L) was reached with the improved yeast extract medium. Finally, culture performance and media improvement was analysed by measuring the oxygen transfer rate as well as the backscatter during shake flask cultivation.

Statistical Optimization of Polysaccharides Production by the Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Agaricomycetes) in Solid-State Fermentation Using Highland Barley Grains.

Ganoderma lucidum is a widely used medicinal mushroom in traditional Chinese medicine that creates a diverse set of bioactive compounds. Highland barley, a typical nutrition-balanced crop, is not convenient for direct consumption but its nutritional characteristics meet the modern requirements of health food. In the present study, barley grains were used as substrates on solid-state fermentation (SSF) of G. lucidum. Statistical optimization of media composition was employed for enhancing the production of polysaccharides. Peptone, medlar, and KH2PO4 were identified as the most important components for producing polysaccharide. Based on the one-factor-at-a-time experimentation, a quadratic regression model with the polysaccharide contents as the response value was established by central composite design (CCD). The results showed that the predicted variables were 2.38% peptone, 1.14% medlar, and 0.25% KH2PO4 for the maximum yield of predicted polysaccharides of 11.64% in the fermented substrate. The experimental polysaccharides obtained using the predicted optimum media composition constituted 11.61% of the fermented substrate, which validates the high degree of accuracy of optimization for enhanced production of polysaccharides by SSF. This study suggested that in the process of barley grains fermentation by G. lucidum for polysaccharides production, the optimized SSF substrate consists of 71.4% barley grains, 2.38% peptone, 1.14% medlar, 0.25% KH2PO4, 2.5% glucose, 0.25% MgSO4 · 7H2O, and 1% CaCO3. According to this study, the strain G. lucidum 00679 showed a good fermentation property by optimizing the media. It might be a candidate industrial strain for further process optimization and scale-up study.

Benefits of Soleris® over the Conventional Method for Enumeration of Microbial Load in Salacia Herbal Extract.

Stems and roots of Salacia genus plants have been used as a specific remedy for early-stage diabetes, and one of the four sulphonium sulphates, salacinol is the compound responsible for the anti-diabetic activity. Salacia is prone to microbial contamination and insect infestation; hence, methods to estimate the microbial load in such plants will enhance its nutritional value. This paper highlights the novel use of Soleris® to quantify microbes of all types, namely bacteria, yeasts, molds, and coliforms in herbal extracts. The microbial analysis results obtained with Soleris® test vial have been compared with the conventional method, and the results indicate that Soleris® is equally efficient as the conventional method and in fact displays several advantages over the traditional method. The Soleris® method is a real time monitoring system that is highly sensitive, user-friendly, and environmentally friendly since it generates very little biomedical waste and saves a large amount of time. The data presented here demonstrate that for highly contaminated samples, results are available within 24 h. For yeasts and molds, the Soleris® method produces results in 48 h, thus offering considerable time savings compared to other commonly used methods.

Effect of Listerine Mouthwash with Green Tea on the Inhibition of Streptococcus Mutans: A Microbiologic Study

Abstract Objective: To evaluate in vitro the antimicrobial effect of Listerine-green tea mouthwash on Streptococcus mutans (SM) in comparison with 0.12% Chlorhexidine (CHX) and Listerine-Zero. Material and Methods: The sensitivity and growth inhibition of SM bacterial species were evaluated and compared between Listerine-green tea, 0.12% CHX and Listerine-Zero mouthwashes. Sixty plates containing SM colonies were prepared in three groups (n=20), and growth inhibition zones were measured using the disk diffusion agar test in mm. Data were analyzed with SPSS 21. One-way ANOVA was used to compare the efficacy of the three mouthwashes tested. Post hoc Tukey tests were used for two-by-two comparisons. Statistical significance was defined at P<0.05. Results: Analysis of data showed significant differences between the three groups (p<0.001); 0.12% CHX was the most effective mouthwash, and Listerine-Zero exhibited the least effect on the growth inhibition of SM (p<0.004). Conclusion: All three mouthwashes were significantly effective in inhibiting the growth of SM. The effect of Listerine-green tea mouthwash was higher than that of Listerine-Zero and less than that of 0.12% CHX.

Identification and characterization of type III polyketide synthase genes from culturable endophytes of ethnomedicinal plants.

Endophytic fungi provide benefits to host plants by producing a diverse class of secondary metabolites (natural products). Arrays of polyketide natural products are synthesized by specific classes of polyketide synthases (PKS I, II and III) in host organisms. In the present study, we attempt to screen and identify type III PKSs in culturable fungal endophytes isolated from the ethno medicinal plants including Arbus precatorius, Bacopa monnieri,Citrus aurantifolia and Datura metel to detect the genetic potential of endophytic fungi in producing bioactive compounds. A total of seventeen endophytic fungal strains belonging to eight genera were identified using fungal morphology and rDNA-ITS phylogenetic analyses. A CODEHOP-PCR based strategy was followed to design degenerate primers for the screening of type III PKS genes from fungal endophytes. We had successfully amplified partial PKS genes from eight endophytes. The amplified PKS sequences showed 60-99% identity to already characterized/putative PKS genes. From the partial sequence of FiPKS from Fusarium incarnatum BMER1, a full-length gene was amplified, cloned and characterized. FiPKScDNA was cloned and expressed in E. coli Lemo21 (DE3) and the purified protein was shown to produce pyrones and resorcinols using acyl-CoA thioesters as substrates. FiPKS showed the highest catalytic efficiency of 7.6 × 104 s-1 M-1 with stearoyl CoA as a starter unit. This study reports the identification and characterization of type III PKS from endophytes of medicinal plants by CODEHOP PCR.

Urinary tract infections in a university hospital: pathogens and antibiotic susceptibility.

BACKGROUND: A substantial group of patients visit the emergency department (ED) with complaints of urinary tract infections (UTI). Treatment advice is based on national and local public health surveillance data. It is unclear whether this advice is adequate for hospitals with selected patient populations, such as university hospitals. METHODS: We performed a retrospective study on patients visiting the ED of the Erasmus University Medical Center (Erasmus MC) in the Netherlands from January 1st, 2013 until December 31st, 2014 with a suspected complicated UTI (cUTI) and positive urinary cultures. Patient data, data concerning the ED visit and microbiological data were analysed. RESULTS: 439 patients visited the ED, of whom 429 had a cUTI. Our results were compared with NethMap data. Distribution of uropathogens was comparable with the overall distribution in the Netherlands. Antibiotic susceptibility was comparable for intravenous antibiotics, but was lower for oral antibiotics. Susceptibility for empiric antibiotic therapy (i.e., cefuroxime and gentamyicin) was 96.2%. Pathogens differed from the index culture in 56.2% 104/185) of the urinary cultures available from the previous year. Using logistic regression, we found that a shorter time between last admission to the initiated antibiotic regimen was associated with lower susceptibility of cultured uropathogens. CONCLUSION: The distribution and antibiotic susceptibility of uropathogens for intravenous antibiotics in a Dutch university hospital is comparable with overall distribution in the Netherlands. Empiric antibiotic therapy in our local guideline appears to be an adequate antibiotic regimen for cUTI and we therefore recommend treating patients accordingly. Extension of the chosen regimen based on earlier cultured pathogens is advised, and narrowing of the antibiotic regimen strongly discouraged.

The potential of commercially available phytotherapeutic compounds as new photosensitizers for dental antimicrobial PDT: A photochemical and photobiological in vitro study.

The present study evaluated the effectiveness of extracts of commercially available Curcuma longa, Citrus lemon, Hamamelis virginiana and Hypericum perforatum as photosensitizers in Antimicrobial Photodynamic Therapy (aPDT). Each photosensitizer (PS) was analyzed in a spectrophotometer between 350 and 750 nm to determine the ideal light source. Once the absorption bands were determined, three light sources were selected. To determine the concentration of use, the compounds were tested at different concentrations on bovine dentin samples to evaluate the risk of staining. Once the concentration was determined, the PSs were evaluated for dark toxicity and phototoxicity on fibroblast and bacteria culture. Each compound was then irradiated with each light source and evaluated for the production of reactive oxygen species (ROS). The bacterial reduction was tested on E. faecalis culture in planktonic form and on biofilm using an energy of 10 J and an Energy Density of 26 J/cm2. The tested compounds exhibited light absorption in three bands of the visible spectrum: violet (405 nm), blue (460 nm) and red (660 nm). At a 1:6 concentration, none of the compounds caused tooth staining as they did not exhibit significant toxicity in the cells or bacterial suspension. Additionally, significant ROS production was observed when the compounds were irradiated at each wavelength. When aPDT was performed on the plactonic and biofilm bacteria, significant microbial reduction was observed in both cases, reaching a reduction of up to 5Logs. In conclusion, extracts of Curcuma longa, Citrus lemon, Hamamelis virginiana and Hypericum perforatum exhibited potential for use as photosensitizing agents in aPDT.