Karina Perrelli Randau

Própolis: atualizações sobre a química e a farmacologia

Propolis (bee glue) is a complex mixture, formed by resinous and balsamic material. Its chemical composition is variable and complex, being related with the flora of each region visited by the bees and with the period of resins collection. Flavonoids, aromatic acids, terpenoids and phenylpropanoids, fatty acids, and other compounds are found in propolis. In the last 30 years, propolis has become subject of intense pharmacological and chemical studies. In different parts of the world it is indicated to improve health and prevent illnesses. Currently, it is available in some pharmaceutical forms as capsules, extracts, mouthrinses, powder form, among others. Indeed, studies correlating the chemical composition with the biological activity are necessary, defining each type of propolis with its therapeutic application. It is an essential task for a market ever bigger and demanding in the whole word.

Total Flavonoids Content in the Raw Material and Aqueous Extractives from Bauhinia monandra Kurz (Caesalpiniaceae)

The aim of this work was to evaluate the spectrophotometric methodology for determining the total flavonoid content (TFC) in herbal drug and derived products from Bauhinia monandra Kurz. Several analytical parameters from this method grounded on the complex formed between flavonoids and AlCl3 were evaluated such as herbal amount (0.25 to 1.25 g); solvent composition (ethanol 40 to 80%, v/v); as well as the reaction time and AlCl3 concentration (2 to 9%, w/v). The method was adjusted to aqueous extractives and its performance studied through precision, linearity and preliminary robustness. The results showed an important dependence of the method response from reaction time, AlCl3 concentration, sample amount, and solvent mixture. After choosing the optimized condition, the method was applied for the matrixes (herbal material and extractives), showing precision lower than 5% (for both parameters repeatability and intermediate precision), coefficient of determination higher than 0.99, and no important influence could be observed for slight variations from wavelength or AlCl3 concentration. Thus, it could be concluded that the evaluated analytical procedure was suitable to quantify the total flavonoid content in raw material and aqueous extractives from leaves of B. monandra.

In Vitro Synergistic Effect of Psidium guineense (Swartz) in Combination with Antimicrobial Agents against Methicillin-Resistant Staphylococcus aureus Strains

The aim of this study was to evaluate the antimicrobial activity of aqueous extract of Psidium guineense Swartz (Araçá-do-campo) and five antimicrobials (ampicillin, amoxicillin/clavulanic acid, cefoxitin, ciprofloxacin, and meropenem) against twelve strains of Staphylococcus aureus with a resistant phenotype previously determined by the disk diffusion method. Four S. aureus strains showed resistance to all antimicrobial agents tested and were selected for the study of the interaction between aqueous extract of P. guineense and antimicrobial agents, by the checkerboard method. The criteria used to evaluate the synergistic activity were defined by the fractional inhibitory concentration index (FICI). All S. aureus strains were susceptible to P. guineense as determined by the microdilution method. The combination of the P. guineense extract with the antimicrobial agents resulted in an eight-fold reduction in the MIC of these agents, which showed a FICI ranging from 0.125 to 0.5, suggesting a synergistic interaction against methicillin-resistant Staphylococcus aureus (MRSA) strains. The combination of the aqueous extract of P. guineense with cefoxitin showed the lowest FICI values. This study demonstrated that the aqueous extract of P. guineense combined with beta lactamics antimicrobials, fluoroquinolones, and carbapenems, acts synergistically by inhibiting MRSA strains.

Variabilidade sazonal dos constituintes da própolis vermelha e bioatividade em Artermia salina

Propolis is a resinous hive product collected by honeybees from plant sources. The composition of the propolis depends on the season, the vegetation, and the area of collection. It presents a diverse biological activities such as antimicrobial, antioxidant and antitumoral. The seasonal variability of the red propolis constituents from Pernambuco State were accomplished in the months of February, June and October of 2006. The volatile red propolis constituients were captured by the dynamic headspace technique and analyzed by GC-MS. In the analysis of the samples, 34 constituents were identified as the mono and sesquiterpens, phenylpropanoids, aldehydes, cetons and n-alcanes, presenting as majority constituents the trans-anethol, α-copaene and methyl cis-isoeugenol. The phytochemistry profile was performed by thin layer chromatography (TLC). Through this technique the majority constituents were identified as phenols. The Brine shrimp bioassay was used to evaluate of the red propolis methanolic extract, which demonstrated a DL50 of 18.9 µg/mL and an activity antitumoral was possibly suggested.

Total phytosterol content in drug materials and extracts from roots of Acanthospermum hispidum by UV-VIS spectrophotometry

Acanthospermum hispidum DC., Asteraceae, is widely used in folk medicine in Brazil to treat respiratory diseases; this biological property has been attributed to its phytosterol content. This study evaluated the spectrophotometric assay method to quantify the total phytosterol content in raw materials and extracts from roots of A. hispidum. The procedure was based on the quantification at 625 nm after the Liebermann-Burchard reaction. The method was evaluated for linearity, repeatability, intermediate precision, accuracy and robustness. The date indicated that the procedure is a valid analytical tool for materials and herbal derivatives from A. hispidum.

Chrysobalanaceae: traditional uses, phytochemistry and pharmacology

Chrysobalanaceae is a family composed of seventeen genera and about 525 species. In Africa and South America some species have popular indications for various diseases such as malaria, epilepsy, diarrhea, inflammations and diabetes. Despite presenting several indications of popular use, there are few studies confirming the activities of these species. In the course of evaluating the potential for future studies, the present work is a literature survey on databases of the botanical, chemical, biological and ethnopharmacological data on Chrysobalanaceae species published since the first studies that occurred in the 60s until the present day.

Cytotoxic and genotoxic effects of ethanolic extract of Euphorbia hyssopifolia L. on HepG2 cells

ETHNOPHARMACOLOGICAL RELEVANCE Euphorbia hyssopifolia L. is a weed with recognized antimicrobial potential employed in Indian, Asian and Latin-American popular medicine. However, little is known with regard to its toxic potential. The present study aimed to investigate the cytotoxic and genotoxic effects of ethanolic extract of E. hyssopifolia in HepG2 cell culture. MATERIALS AND METHODS Phytochemical screening of ethanolic extract was carried out to determine the presence of active secondary plant metabolites. Six concentrations (0.00001, 0.0001, 0.001, 0.01, 0.1 and 1.0mg/mL) of ethanolic extract were tested by the MTT assay to verify cytotoxicity. Then, genotoxic evaluations (alkaline comet assay and cytokinesis-block micronucleus assay - CBMN) were carried out in HepG2 cells with extract concentrations of 0.01, 0.1 and 1.0mg/mL. RESULTS Mono and sesquiterpenes, triterpenes and steroids, and flavonoids were the main classes found in the phytochemical screening. Extract concentrations used in the MTT assay showed no cytotoxic activity. On the other hand, genotoxic activity was verified at 0.1 and 1.0mg/mL in the alkaline comet assay. Additionally, the 1.0mg/mL concentration induced severe cell damage leading to death in the CBMN assay, indicating a cytotoxic effect for this concentration in the latter method. CONCLUSION The use of E. hyssopifolia extract for medicinal purposes should be avoided, because concentrations above 0.01mg/mL may pose risk to human health due to cytotoxic and/or genotoxic effects.

Chemical composition, antioxidant and topical anti-inflammatory activities of Croton cordiifolius Baill. (Euphorbiaceae)

Croton cordiifolius is widely used in Brazilian Caatinga folk medicine to treat general inflammation, pain, and gastrointestinal disturbances. Currently, its medicinal properties are not well understood, owing to the absence of chemical and pharmacological studies. The aims of this work were to analyze the chemical composition of C. cordiifolius stem bark and evaluate its in vitro antioxidant and in vivo anti-inflammatory activities. C. cordiifolius ethanolic extract (CcEE) was obtained by maceration, while essential oil (CcEO) was extracted by hydrodistillation in a Clevenger-type apparatus. The chemical composition was evaluated by thin-layer chromatography and GCMS. Total phenolics, flavonoids, and antioxidant activity were quantitated by spectrophotometry. Topical anti-inflammatory activity was evaluated by different ear edema models in mice. The major compounds in CcEO were α-pinene (51.76%) and β-pinene (19.08%). CcEE analysis indicated the presence of alkaloids, mono- and sesquiterpenes, flavonoids, phenylpropanoids, triterpenes, steroids, and coumarins. CcEE showed antioxidant activity in vitro. In a topical anti-inflammatory assay, CcEO showed no activity. On the contrary, CcEE inhibited ear edema induced by phorbol 12-myristate 13-acetate (PMA), arachidonic acid (AA), ethyl phenylpropriolate (EPP), and phenol. Probable mechanisms include inhibition of AA metabolite biosynthesis, vasoactive amine activity, and cytokine release/activity. These results corroborate the popular reputation of C. cordiifolius as an anti-inflammatory remedy. Key words: Croton cordiifolius, Euphorbiaceae, caatinga, topical anti-inflammatory activity, ear edema.

Morfoanatomia, histoquímica e perfil fitoquímico de Priva lappulacea (L.) Pers. (Verbenaceae)

This study describes the anatomy and analyzes the histochemistry of the vegetative organs of Priva lappulacea (L.) Pers. Freehanded transversal and paradermal sections of fresh and fixed material were used for the anatomical and histochemical analyses, using optical microscopy. The anatomical characters are common to those described for the family, being able to be used to diagnosis in its identification. The leaves are highlighted by the presence of glandular and non-glandular trichomes, anomocytic stomata on both faces of the epidermis and dorsiventral mesophyll. The expansions in the petiole are added to the diagnosis of this species. The phytochemical study carried out with aerial organs showed the presence of triterpene (ursolic acid) and steroid (β-sitosterol), iridoids (ipolamide and catalpol), reducing sugar (glucose), flavonoid (luteolin) and fenilpropanoid (verbascosides). In the roots only glucose was found and two iridoids are present in stem and leaves. Alkaloids, saponins, cumarines, cinamic acid derivates, condensed proantocianidines and leucoantocianidines were not checked in the analyzed parts. The anatomical description and the histochemical tests are unpublished for P. lappulacea.

Microscopic Characterization of Croton cordiifolius Baill. (Euphorbiaceae)

Background: Croton cordiifolius Baill. is popularly known as “quebra-faca” in the Brazilian Northeast and is used to treat general inflammation, pain, and gastrointestinal disturbances. Objective: This paper aims to study the anatomical characteristics of C. cordiifolius. Materials and Methods: Cross-sections and paradermic sections of root, stem, petiole and leaf blade were obtained by hand and submitted to double staining with astra blue and safranin process for the anatomical study. Maceration was performed according to the method of Jeffrey. Results: The secondary root has peridermis, parenchymatic cortex, collateral vascular system surrounded by sclerenchyma. The secondary stem has peridermis, cortical region with lignified cells, isolated groups of fibers, laticifers, prismatic crystals, druses and starch. The vascular system of the stem is bicollateral. The petiole and the leaf blade have stellate, simple and glandular trichomes. The leaf blade is hypostomatic, with paracytic stomata. The mesophyll is isobilateral and the midrib shows a concave-convex contour. Laticifers occur in stem, petiole and leaf blade. Prismatic crystals and druses are found in all organs analysed. Through the maceration it was possible to identify the type of vessel elements. Conclusion: The anatomical features are useful for differentiation of other species of Croton and provide support to their quality control.