Virtual screening of secondary metabolites of the genus Solanum with potential antimicrobial activity

ABSTRACT Infectious diseases are a health problem today and have high mortality rates with a wide diversity of potentially pathogenic microorganisms. Research that is based either on the search for new drugs from plants or on the improvement of phytotherapeutics is prominent and continues to play an important role nowadays. From this perspective, use of in silico studies to carry out investigations of new molecules potentially active for methicillin-resistant Staphylococcus aureus and Escherichia coli using an in-house database with 421 different secondary metabolites selected from the literature from Solanum genus was performed. We also realized an in vitro study with strains of S. aureus and E. coli and compared the results. Two databases from ChEMBL were selected, the first one with activity against methicillin-resistant S. aureus and another against E. coli. The compounds were classified according to the pIC50 values to generate and validate the model using a "Random Forest". The "Random Forest" prediction model for methicillin-resistant S. aureus obtained an accuracy of 81%, area under the Receiver Operating Characteristic curve of 0.885, selecting eight molecules with an active potential above 60%. The prediction model for E. coli obtained an accuracy rate of 88%, area under the Receiver Operating Characteristic curve of 0.932, selecting four molecules with potential probability above 84%. Rutin proved to be potentially active in the in silico study for S. aureus and E. coli. Microbiological tests have shown that rutin has activity only for E. coli. An interaction study with strains of S. aureus ATCC 25923, a standard strain sensitive to all antibiotics, and SAM-01, a multidrug-resistant strain, was designed. There was interaction only between rutin and oxacillin, one of the three antibiotics studied in the interaction, for the strain SAM-01, reducing the resistance of this strain.

Isoflavone formononetin from red propolis acts as a fungicide against Candida sp

Abstract A bioassay-guided fractionation of two samples of Brazilian red propolis (from Igarassu, PE, Brazil, hereinafter propolis 1 and 2) was conducted in order to determine the components responsible for its antimicrobial activity, especially against Candida spp. Samples of both the crude powdered resin and the crude ethanolic extract of propolis from both locations inhibited the growth of all 12 tested Candida strains, with a minimum inhibitory concentration of 256 µg/mL. The hexane, acetate and methanol fractions of propolis 1 also inhibited all strains with minimum inhibitory concentration values ranging from 128 to 512 µg/mL for the six bacteria tested and from 32 to 1024 µg/mL for the yeasts. Similarly, hexane and acetate fractions of propolis sample 2 inhibited all microorganisms tested, with minimum inhibitory concentration values of 512 µg/mL for bacteria and 32 µg/mL for yeasts. The extracts were analyzed by HPLC and their phenolic profile allowed us to identify and quantitate one phenolic acid and seven flavonoids in the crude ethanolic extract. Formononetin and pinocembrin were the major constituents amongst the identified compounds. Formononetin was detected in all extracts and fractions tested, except for the methanolic fraction of sample 2. The isolated isoflavone formononetin inhibited the growth of all the microorganisms tested, with a minimum inhibitory concentration of 200 µg/mL for the six bacteria strains tested and 25 µg/mL for the six yeasts. Formononetin also exhibited fungicidal activity against five of the six yeasts tested. Taken together our results demonstrate that the isoflavone formononetin is implicated in the reported antimicrobial activity of red propolis.

Avaliação clínica de três métodos de anestesia com cloridratos de bupivacaína em cirurgias de terceiros molares inferiores retidos / Clinical comparative way the effectiveness of three work methods with bupivacaine chloridrate im impacted lower third molars surgery

No presente trabalho avalia-se clinicamente se foram comparativa a eficácia de três métodos de trabalho com o Cloridrato de Bupivacaína a 0,5 por cento com Epinefrina 1:2000.000 em cirurgias de terceiros molares inferiores retidos. Apesar de algumas desvantagens, a Bupivacaína demostrou ser um anestésico versátil, que permite variações dos métodos de trabalho, podendo aproveitar as melhores propriedades de cada associação. Assim, pode-se controlar o inicio da anestesia, sua duração, analgesia, quantidade de medicamentos e outras propriedades, podendo até condicionar ou personalizar a anestesia ao tipo de cirurgia ou paciente

Antimicrobial activity of a mixture of two isomeric phenylpropanoid glycosides from Arrabidaes harleyi A.H. Gentry(Bignoniaceae)

Arrabidaea harleyi A.H. Gentry (Bignoniaceae) is an ornamental plant found in some regions of the Atlanticforest in Brazil. From its bark a mixture of verbascoside and isoverbascoside was isolated. This mixture was shown to be active against Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Bacillus mycoides, Enterecoccus faecalis, Escherichia coli, Serratia marcensis and Candida albicans. The minimal inhibitory concentration (MIC) was established by diffusion method