Micheline A. Lima

Alcalóides de Duguetia trunciflora Maas (Annonaceae)

From the ethanolic extract of the leaves and thin branches of Duguetia trunciflora Maas (Annonaceae) six alkaloids were isolated, being one benzylisoquinoline: reticuline1, four tetrahydroprotoberberine:,tetrahydro-palmatine2, tetrahydrojathrorrizine3, discretamine4, thaicanine5, and one berberine: jathrorrizine6. These alkaloids were identified through 1H and 13C NMR spectroscopic technics. The alkaloids 1, 3, 5 and 6 are being cited for the first time on Duguetia genus.

Fe (II) ADSORPTION ON Ucides cordatus CRAB SHELLS

In this study Ucides cordatus crab shells were utilized as Fe (II) sorbent as material of low cost and simple preparation. Values of pH of standard solution, biosorbent mass, particles size, contact time (tc) and initial concentration of the standard solution were optimized. The best conditions were pH = 2.00, tc = 840 min and Mc = 0.25 g. The kinetic pseudo first-order model displayed the best description of the adsorption process and the equilibrium study showed that the Langmuir model better describes the adsorption of the Fe (II). There is great affinity between the Fe (II) and the biosorbent.

Modulatory antimicrobial activity of Piper arboreum extracts

Abstract The side effects of certain antibiotics have been a recent dilemma in the medical arena. Due this fact, the necessity of natural product discovery could provide important indications against several pharmacological targets and combat many infectious agents. Piper arboreum Aub. (Piperaceae) has been used by Brazilian traditional communities against several illnesses including rheumatism, bronchitis, sexually transmitted diseases and complaints of the urinary tract. Medicinal plants are a source of several remedies used in clinical practice to combat microbial infections. In this study, ethanol extract and fractions of Piper arboreum leaves were used to assay antimicrobial and modulatory activity. The minimum inhibitory concentration (MIC) was determined using microdilution method of ethanol extract and fractions from the leaves of P. arboreum ranging between 8 and 1024 μg mL-1. The capacity of these natural products to enhance the activity of antibiotic and antifungal drugs was also assayed. In these tests, natural products were combined with drugs. The natural products assayed did not demonstrate any clinically relevant antimicrobial activity (MIC ≥ 1024 μg mL-1). However, the modulation of antibiotic activity assay observed a synergistic activity of natural products combined with antifungal (such as nystatin and amphotericin B) and antibiotic drugs (such as amikacin, gentamicin and kanamycin). According to these results, these natural products can be an interesting alternative not only to combat infectious diseases caused by bacteria or fungi, but also to combat enhanced resistance of microorganisms to antibiotic and antifungal drugs.

Evaluation of antibacterial, antifungal and modulatory activity of methanol and ethanol extracts of Padina sanctae-crucis

BACKGROUNDnMulti-resistantmicroorganisms such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida tropicalis e Candida krusei are the main causes of microbial infections. Padina sanctae-crucis is a seaweed often used to check the contamination of ecosystems by materials such as heavy metals, but studies of the antimicrobial activity of the same seaweed were not found.nnnMETHODSnThe tests for the minimum inhibitory concentration and modulation of microbial resistance, with the use of ethanolic and methanolic extracts of Padina Sanctae-cruces combined with drugs of the class of aminoglycosides and antifungal were used to evaluate the activity against the cited microorganisms.nnnRESULTSnWas observed a modulation of antibiotic activity between the natural products and the E. coli and S. aureus strains, indicating a synergism and antagonism respectively.nnnCONCLUSIONSnThe results showed a moderate modulatory effect against some microorganisms studied.

Herbs in association with drugs: Enhancement of the aminoglycoside-antibiotic activity by Pityrogramma calomelanos (L.) Link

AIMSnIn this work, the ethyl acetate and hexane fractions of Pityrogramma calomelanos (L.) were evaluated to antibacterial and antifungal activity against strains of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, Candida krusei and Candida tropicalis.nnnMETHODSnThe study was performed aiming to assess the antimicrobial effect with the method of dilution in HIA. The hexane and ethyl acetate fractions were named HFPC and EAFPC, respectively.nnnRESULTSnBoth fractions of specie P.xa0calomelanos displayed good activity against S.xa0aureus when associated with gentamicin. When associated with the antifungal, the fractions did not exhibit relevant activity against species of Candida.nnnCONCLUSIONSnThese results indicate that this specie can be used as a possible source of natural products of antibacterial interest, mainly when combined with aminoglycosides.