Evaluation in vitro of antimicrobial activity of tucumã oil (Astrocaryum Vulgare)

Hospital Infection is a major health problem and affects around 1.5 million people annually around the world. The Amazon region has a wide diversity of native palm trees that have fruits and oilseeds. Astrocaryum vulgare, commonly known as Tucumã in Brazil, belongs to the family Arecaceae. This palm has orange, fleshy, single-egg-shaped fruits that are used for therapeutic purposes in diseases of the eyes and skin due to the high content of carotenoids, oil is used in cooking, health treatment and massage. This study evaluated the antimicrobial activity of the Tucumã oil against 18 microorganisms. The antimicrobial activity of Tucumã was measured through the determination of the Minimum Inhibitory Concentration (MIC), as well as the determination of the Minimum Microbicidal Concentration (CMM) aiming to contribute to the discovery of new antimicrobials against pathogenic microorganisms’ human health and may contribute to the treatment of nosocomial infections. The results showed that the oil of Tucumã presented antimicrobial activity against five important bacteria, four Gram - positive bacteria (Enterococcus faecalis, Enterococcus faecium, Staphylococcus epidermidis and Streptococcus agalactiae) and one Gram - negative (Acinetobacter baumannii)

Detection and characterization of Bacillus cereus isolated from the dialysis fluid

In this study, B. cereus was detected in dialysis fluids within international parameters (ultrapure – maximum limit of 0.1 CFU/mL for heterotrophic bacteria count) by analyzing the pellet obtained through the centrifugation method. We also investigated the ability of the B. cereus isolate to form a biofilm at different temperatures, the production of virulence factors, and the susceptibility to commercial antimicrobial agents. This study demonstrated a high ability of B. cereus to persist in the hemodialysis system, which can be explained by its broad ability to produce a biofilm at 25 °C, its relevant production of virulence factors, such as β-hemolysin, lecithinase and cereulide, and its important resistance pattern to antimicrobial drugs. In conclusion, these new findings expand the understanding that this microorganism should not be neglected and new methods for tracking it should be considered

ANTIMICROBIAL PEPTIDE P34 INFLUENCES GENE EXPRESSION OF LISTERIA MONOCYTOGENES GROWING IN SOFT CHEESE

Objective: To evaluate whether antimicrobial substances produced by autochthonous lactic acid bacteria (LAB) from Minas Frescal cheese are able to enhance the activity of bacteriocin P34 against Listeria monocytogenes and investigate the influence of P34 in specific gene expression of this bacterium after the inoculation in Minas Frescal cheese.Methods: Bacillus sp. P34 and L. monocytogenes ATCC 7644 were used in this study. The antimicrobial peptide P34 was purified and applied (0, 800 or 6400 AU/ml) to cheese surface before inoculation with L. monocytogenes. Antimicrobial activity and synergism were detected using the agar diffusion technique. Expression levels of D-Alanine-D-alanyl carrier protein ligase (dltA), Putative phospholipid lysinylation (Imo 1695) and EIIABMan of mannose-specific PTS (mptA) mRNAs in bacteriocin-treated L. monocytogenes growing in Minas Frescal cheese were determined using real-time PCR.Results: The peptide P34 showed increased antilisterial activity when combined with culture supernatants of some selected LAB isolated from Minas Frescal cheese. The addition of peptide P34 to cheese caused a decrease of up to 3 log cycles in viable counts of artificially inoculated L. monocytogenes. The influence of peptide P34 on the expression of genes associated with components of the cell surface of L. monocytogenes was investigated by real-time PCR. A significant increase in the expression of the genes dltA, Imo 1695 and mptA was observed after 96 h in the presence of peptide P34.Conclusion: These results suggest that the peptide P34 influences the expression of genes involved in D-alanylation of teichoic acids and lipoteichoic acids and lysination of the cell membrane of phospholipids

Antibacterial and antibiofilm activity of Physalis peruviana calyx extract / Atividade antibacteriana e antibiofilme do extrato do cálice de Physalis peruviana

This study aimed to evaluate the antibacterial and antibiofilm activity of a P. peruviana calyx extract. Goldenberry calyx extracts were prepared with 60% (v/v) ethanol. Minimum inhibitory concentration (MIC) analyses were performed by the 96-well plate microdilution method together with the minimum bactericidal concentration (MBC). Biofilm inhibition and destruction was performed in microdilution plates. The P. peruviana calyx extract presented antibacterial activity against the pathogens analyzed (Enterobacter aerogenes ATCC 13048, Klebsiella pneumoniae ATCC 1705, Staphylococcus epidermidis (clinical isolate), Streptococcus pneumoniae ATCC 99619, Pseudomonas aeruginosa PA01, Enterococcus faecalis ATCC 29212, Escherichia coli (clinical isolate), Shigella sonnei (clinical isolate), Acinetobacter baumannii ATCC 19606, Streptococcus agalactie (clinical isolate), Acinetobacter baumannii (clinical isolate), Salmonella sp. (clinical isolate), Salmonella enteritidis (clinical isolate), and Staphylococcus aureus (clinical isolate)). MIC varied from 3.15 to 30 mg/mL extract and showed bacteriostatic activity against eight pathogens and bactericidal activity at 30 mg/mL concentration against six strains. Biofilm tests revealed biofilm formation inhibition, although there was no destruction. According to these results, the potential antibacterial activity of P. peruviana calyx extract was verified. This will enable further studies to be carried out to contribute to its use in the food industry as a preservative of natural origin and other clinical applications

Sífilis adquirida: uma revisão epidemiológica dos casos em adultos e idosos no município de Porto Alegre/RS

Background and Objectives: It is known that acquired syphilis, in the “gaúcho” epidemiological scenario, is a disease of extreme importance due to its high prevalence and rise. From this, the following work aims to review the measures used in the care of adult and elderly patients diagnosed with acquired syphilis and its epidemiology in the city of Porto Alegre / RS. Contents: According to data published in 2016 by the Ministry of Health, the growth of syphilis infection in adults and elderly individuals is in great expansion in Brazil. Through the achievements of the elderly in the last decades, the prolongation of sexual life is a point worth highlighting, besides the incentive to socialization and the lack of information on sexual health. Conclusion: Sexually transmitted infections grow in these two publics and more effective preventive measures in the field of public health are needed. Keywords: Syphilis. Communicable Diseases. Public Health. Infectious Disease.Justificación y Objetivos: Se sabe que la sífilis adquirida, en el escenario epidemiológico”gaúcho”, se configura como una enfermedad de extrema importancia debido a su alta prevalencia y ascenso. A partir de ello, el siguiente trabajo busca revisar las medidas utilizadas en la asistencia de los pacientes adultos y ancianos con diagnóstico de sífilis adquirida y su epidemiología en la ciudad de Porto Alegre /RS. Contenido: Según datos publicados en 2016 por el Ministerio de Salud, el crecimiento de la infección por sífilis en individuos adultos y ancianos está en gran expansión en Brasil. A través de los logros alcanzados por los ancianos en las últimas décadas, la prolongación de la vida sexual es un punto merecedor de hincapié, además del incentivo a la socialización y la falta de información sobre salud sexual. Conclusiones: Las infecciones sexualmente transmisibles crecen en estos dos públicos y se necesitan medidas preventivas más efectivas en el ámbito de la salud pública. Palabras-clave: Sífilis. Enfermedades transmisibles. Salud pública. Enfermedades infecciosasJustificativa e Objetivos: Sabe-se que a sífilis adquirida, no cenário epidemiológico gaúcho, configura-se como doença de extrema importância devido a sua alta prevalência e ascensão. A partir disso, o seguinte trabalho visa revisar as medidas utilizadas na assistência dos pacientes adultos e idosos com diagnóstico de sífilis adquirida e sua epidemiologia no município de Porto Alegre/RS. Conteúdo: Segundo dados publicados em 2016 pelo Ministério da Saúde, o crescimento da infecção por sífilis em indivíduos adultos e idosos está em grande expansão no Brasil. Através das conquistas pelos idosos nas últimas décadas, o prolongamento da vida sexual é ponto merecedor de destaque, além do incentivo à socialização e a falta de informação sobre saúde sexual. Conclusão: As infecções sexualmente transmissíveis crescem nestes dois públicos e necessita-se medidas preventivas mais efetivas no âmbito da saúde pública. Descritores: Sífilis. Doenças Transmissíveis. Saúde Pública. Doenças infecciosas

Repellent Effects of Andiroba and Copaiba Oils against Musca domestica (Common House Fly) and Ecotoxicological Effects on the Environment

Background: The main challenge in raising cattle in Brazil is related to ectoparasites, that cause negative effects on milk and meat production, and in severe cases, animal death. Sheds known as crèches attracts large number insects mainly due to milk residues in the environment. The housefly is a major problem due to act as vectors of many other diseases, and so there is the possibility of control of infestations with natural products. Andiroba and copaiba oils may act as natural biocides, there are only a few studies on their effect on biological soil parameters. Therefore, this study aimed to evaluate the repellent effect of andiroba and copaiba oils against flies and on biological soil parameters.Materials, Methods & Results: The repellency effect of oils of andiroba and copaiba was tested at a concentration of 5% in lambs shed maternity, containing 64 bays (1.8 m2). It was sprayed 30 mL per pen, where they were housed five lambs each. Pre-treatment counts were taken before the treatment (mean 46 per pen after Musca domestica), and post-treatment count was made on 2, 24 and 48 h. The data collected at 2 and 24 h was evaluated and the number of flies was reduced significantly (P 0.05). Ecotoxicological test using increasing concentrations in the soil (0, 1, 5, 10, 25, 50, and 100 mg/kg) regarding changes in basal respiration (C-CO2), and survival and reproduction of springtails (Folsomia candida). It was observed an increased amount of mineralized C-CO2 until the day 10 of incubation for both oils without inhibition of the microbial respiratory process in any dose. The copaiba oil showed higher amounts of accumulated C-CO2 compared to andiroba oil in all studied concentrations (P 0.05), the same was observed for the reproduction results, where there was no reduction in the number of juveniles (P > 0.05).Discussion: According literature, andiroba and copaiba oils have repellent effect against domestic fly when sprayed onto infected cow’s horn fly, similar results also were reported in vitro tests against M. domestica larvae using andiroba oil and noted 80% larval mortality. The use of natural products in disease control is growing, but its impacts on the environment are not known, so in addition to suggesting therapies it is important to be concerned with ecotoxicological tests. Researchers showed an effect of Eucalyptus globulus essential oil on F. candida and reported 76% reduction in its survival rate at concentration of 60 mg/kg soil.  Basal soil respiration is a sensitive indicator that quickly reveals changes in the environmental conditions that affect microbial activity, and the data presented herein reveal an increase in the respiration of microorganisms depending on the amount of oil added to the soil.  The essential oils of copaiba and andiroba have repellent effect against Musca domestica, and did not show any toxicity to inhibit microbial activity in the soil. In addition, the presence of the oils in the soil did not affect the survival and reproduction of springtails Folsomia candida

Insecticidal Action of Glycerol Monolaurate against the Lesser Mealworm (Alphitobius diaperinus) and its Ecotoxicological Effect on Enchytraeus crypticus

Background: Alphitobius diaperinus, known as the lesser mealworm, is recognized as a problem for the poultry production sector. Several chemical methods have been employed in an attempt to control it, without successful results. Thus, alternative methods should be considered as an interesting approach to control this type of infestation. A recent study showed that glycerol monolaurate (GML) possesses insecticidal effect against bees. Therefore, the aim of this study was to evaluate, for the first time, the effect of GLM against the larval and adult forms of the lesser mealworm in vitro, and to verify whether GLM treated poultry litter used as soil fertilizer exerts any negative effect on its fauna.Materials, Methods & Results: In vitro tests were performed using three concentrations of GLM: 0.2, 0.4 and 1 mg mL-1, and the number of dead larvae and adults of A. diaperinus was counted on days 0, 2, 5 and 8 post-treatment. Poultry litter was pulverized with 1 mg mL-1 of GML, maintained under controlled conditions for 20 days and revolved every two days. Two ecotoxicological tests were performed using Enchytraeus crypticus. In the first test, GML was applied directly into the soil at doses of 0.5, 1 and 2 mg kg-1 of soil, while the second test used poultry litter as soil fertilizer at concentrations of 0, 2, 4 and 8 tons per hectare. Insecticidal action of GML against larvae and adults of A. diaperinus where only the 1 mg mL-1 concentration showed positive effect. GML caused 100% mortality of larvae two days after the beginning of treatment. Similarly, GML showed high efficacy to control adult forms of A. diaperinus, causing 83 and 90% of mortality on days 5 and 8 post-treatment, respectively. No difference was observed while applying GML directly at doses of 0.5, 1 and 2 mg kg-1 in the TAS when compared to the control group, similarly to what was observed using poultry litter containing 1 mg/m2 of GML at concentrations of 0, 2, 4 and 8 tons per hectare compared to the control group.Discussion: GML treatment exerted larvicidal and insecticidal action in vitro against A. diaperinus, similarly to what was observed by researchers against bees, where this product was able to eliminate 55% of the bees after 120 h of treatment. GML insecticidal mechanism of action is poorly investigated and remains unknown. However, there are evidences regarding its antimicrobial property using Staphylococcus aureus, Streptococcus spp., Enterococcus faecalis, as well as its capacity to inhibit some virulence factors linked to antimicrobial resistance. Some tests have been performed in order to reduce the use of chemical products, as Melaleuca alternifolia (tea tree oil), Ocotea odorifera (popularly known as sassafras) and Eucalyptus viminalis (popularly known as eucalypt) essential oils exerts insecticidal action against the larvae and adults of mealworms. The main chemical used to control A. diaperinus is cypermethrin, a chemical product that can damage the soil fauna due to its intensive utilization. The use of GML did not cause negative effects in the soil fauna, in disagreement other study with GML at concentrations of 50 and 100 µg mL-1 and found negative effects on the soil fauna using adults and juvenile forms of springtails (Folsomia candida) as biomarkers, showing a LD50 of 41 µg mL-1. Based on these evidences, we can suggest that the toxicity of GML to soil fauna is related to the biomarker used to determine the toxicity. Therefore, it is possible to conclude that GML possesses insecticidal action without toxic effects for the soil fauna, demonstrating potential as an alternative method to control the lesser mealworm

The influence of different culture media on Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus biofilm formation

Microorganisms such as Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus are frequently isolated in samples of urinary, blood, intestinal, and respiratory infections, among others. These bacteria are also associated with microbial biofilm formation. E. coli, P. aeruginosa, and S. aureus biofilm infections are particularly hard to manage and often associated with nosocomial problems. This study investigated the influence of different culture media on E. coli, P. aeruginosa, and S. aureus biofilm formation. Bacterial performance was evaluated in brain heart infusion broth, Mueller-Hinton broth, or tryptic soy broth, with or without supplementing with different glucose levels (1-5%). The study quantified biofilm biomass and the count of viable biofilm colonies. This is the first study that compares the biofilm formation of E. coli, P. aeruginosa and S. aureus in polystyrene using different culture media and with different glucose concentrations. The most robust growth of E. coli, P. aeruginosa, and S. aureus occurred in brain heart infusion broth supplemented with 5% glucose, Mueller-Hinton broth without glucose, and tryptic soy broth with 2% glucose, respectively. Our data demonstrate that behavioral and morphological characteristics of each bacterium require a specific broth to enhance the growth of these microorganisms. These findings will contribute to future tests for therapeutic alternatives with anti-biofilm potential