Microorganisms Of Medical Importance Research Articles

Metabolic profiling, ADME pharmacokinetics, molecular docking studies and antibacterial potential of Phyllantus muellerianus leaves

Global increase in the level of antimicrobial resistance among bacterial pathogens has prompted the search for alternative treatment from medicinal plants. Phyllantus muellerianus leaves has been used traditionally against microorganisms of medical importance, hence the need to evaluate the pharmacological pathways and mode of actions using in vitro and in silico approaches. Clinical isolates of eight (8) microorganisms associated with urinary tract infections were obtained and identified using morphological and biochemical methods. Phyllantus muellerianus leaves were extracted and purified by solvent partitioning. Ethyl acetate fraction of PM had the highest yield and zone diameter range from 13.5 ± 1.00 to 28 ± 1.53 mm. The rate of protein leakage per time interval of Staphylococcus aureus increased from 9.29 μg/ml at 0 min to 17.43 μg/ml at 120 min while leakage in Candida albicans also increased from 8.57 μg/ml at 0 min to 70.43 μg/ml at 120 min. GCMS fingerprints, pharmacodynamics and pharmacokinetic studies revealed the active agent as quindoline, an azaindole and isotere of indoles having a binding energy of −9.1 kcal/mol. Analyses of the structural and atomic orientations of quindoline, and superimposition on ciprofloxacin, a common antibiotic revealed an interesting comparison, effecting a stronger binding affinity of Quindoline-HMG-CoA complex.

Detection and identification of medically important microorganisms isolated from pigeon excreta collected in a university in a newly industrialized country

A exposição humana a fezes de animais contaminados com microrganismos patogênicos representa um risco para a saúde. A presença de fungos e leveduras em ambientes está relacionada a efeitos adversos na saúde respiratória. A abordagem objetiva para a mitigação de possíveis efeitos à saúde devido à exposição a fungos e leveduras em ambientes fechados é difícil devido à falta de diretrizes. O objetivo deste trabalho foi conhecer as condições higiênico-sanitárias, identificar e caracterizar organismos de importância médica isolados de fezes de pombos coletadas na laje de um telhado de um prédio público. Para tais pontos, a coleta de excrementos foi estabelecida e os microrganismos foram identificados por métodos bioquímicos e microbiológicos padronizados, seguidos da abordagem proteômica de MALDI-TOF para a identificação do nível de espécie. Os resultados da identificação microbiana revelaram a presença de microrganismos de importância médica nas amostras analisadas, a saber: Candida krusei, Candida rugosa, Aspergillus spp., Cryptococcus neoformans, Klebsiella pneumoniae e Trichosporon asahii. Os resultados encontrados revelam a necessidade do desenvolvimento de metodologias que permitam mitigar os riscos à saúde humana devido à exposição a agentes patogênicos no ambiente examinado.

Isolation of bacteria from the digestive tract of Periplaneta americana and Polyphaga aegyptiaca (Blattodea: Blattidae) in Khuzestan Province, Southwestern Iran

Cockroaches are one of the most common household pests carrying different microorganisms of medical importance. The aim of this research was to isolate, characterise and do a susceptibility profiling using disk diffusion method of bacteria from the digestive tract of Periplaneta americana and Polyphaga aegyptiaca. A total of 139 cockroaches were collected between May and December 2015, in Khuzestan Province of Iran. Bacterial species were isolated from the digestive tract of both P. americana and P. aegyptiaca. Among the 139 cockroaches collected, 126 (90.6%) were found to harbour one or more species of bacteria in their digestive tract. There was significant difference in the overall positivity rates of P. americana (93.6%) and P. aegyptiaca (61.5%) (p < 0.05). Eighteen species of bacteria were isolated from the two species of cockroaches. Antibiotic resistance was found in Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Serratia marcescens and Proteus mirabilis isolated from the cockroaches digestive tract. This is the first study where isolation of bacteria with antibiotic resistance to P. aegyptiaca was observed. The findings of the present study revealed and confirmed that P. americana and P. aegyptiaca are important agents in transmission of bacterial pathogens. Health education on control and prevention methods of cockroaches and their role in transmission of diseases in communities especially the study area Dezful County in Khuzestan province, southwestern Iran is recommended.

Antimicrobial Activity and Stability of Short and Long Based Arachnid Synthetic Peptides in the Presence of Commercial Antibiotics.

Four antimicrobial peptides (AMPs) named Pin2[G], Pin2[14], P18K and FA1 were chemically synthesized and purified. The four peptides were evaluated in the presence of eight commercial antibiotics against four microorganisms of medical importance: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The commercial antibiotics used were amoxicillin, azithromycin, ceftriaxone, gentamicin, levofloxacin, sulfamethoxazole, trimethoprim and vancomycin. The best AMP against P. aeruginosa was the peptide FA1, and the best AMP against S. aureus was Pin2[G]. Both FA1 and Pin2[G] were efficient against E. coli, but they were not effective against K. pneumoniae. As K. pneumoniae was resistant to most of the commercial antibiotics, combinations of the AMPs FA1 and Pin2[G] were prepared with these antibiotics. According to the fractional inhibitory concentration (FIC) index, the best antimicrobial combinations were obtained with concomitant applications of mixtures of FA1 with levofloxacin and sulfamethoxazole. However, combinations of FA1 or Pin2[G] with other antibiotics showed that total inhibitory effect of the combinations were greater than the sum of the individual effects of either the antimicrobial peptide or the antibiotic. We also evaluated the stability of the AMPs. The AMP Pin2[G] manifested the best performance in saline buffer, in supernatants of bacterial growth and in human blood plasma. Nevertheless, all AMPs were cleaved using endoproteolytic enzymes. These data show advantages and disadvantages of AMPs for potential clinical treatments of bacterial infections, using them in conjunction with commercial antibiotics.

Habitat influences on diversity of bacteria found on German cockroach in Beijing

Cockroaches are worldwide indoor pests carrying microorganisms of medical importance. German cockroaches (Blattella germanica) were sampled in five habitats (hospital, restaurant, office home, and market) in Beijing, and the bacteria were isolated from their external surface and alimentary tract and identified using a Biolog identification system. Cockroach densities significantly differed among habitats (market > home > office > restaurant > hospital). However, no significant differences in bacterial abundance carried by individual German cockroaches (of either sex) were found among habitats. The bacterial abundance in the gut was significantly higher than that on the surface. There were no significant differences in bacterial species richness observed among habitats, sex, carrying position or their interaction. Cluster analysis showed that cockroach densities and bacterial abundance found in the market differed significantly from the other four habitats. The bacterial diversity was not significantly reduced in sensitive facilities such as hospital and restaurant, even though pesticide and bactericide were more frequently applied there. The implications of these findings were discussed in this article.