Tereza Cristina dos Santos

Snake Venom: Any Clue for Antibiotics and CAM?

Lately several naturally occurring peptides presenting antimicrobial activity have been described in the literature. However, snake venoms, which are an enormous source of peptides, have not been fully explored for searching such molecules. The aim of this work is to review the basis of antimicrobial mechanisms revealing snake venom as a feasible source for searching an antibiotic prototype. Therefore, it includes (i) a description of the constituents of the snake venoms involved in their main biological effects during the envenomation process; (ii) examples of snake venom molecules of commercial use; (iii) mechanisms of action of known antibiotics; and (iv) how the microorganisms can be resistant to antibiotics. This review also shows that snake venoms are not totally unexplored sources for antibiotics and complementary and alternative medicine (CAM).

Development of a Profitable Procedure for the Extraction of 2-H-1-Benzopyran-2- one (Coumarin) from Mikania glomerata

This report deals with a new procedure suitable for the extraction of coumarin 1 from Mikania glomerata, The aim of this investigation is to obtain this compound in an economically profitable way, taking into account the yield of its extraction, the cost, and the time of the overall process. Fresh and dried plants collected in several areas of the State of Rio de Janeiro were used, and seasonal effects on coumarin content were studied. Obtained results indicated that extraction with a 1% (w/v) NaOH solution, under appropriate conditions, allows a simple and complete recovery of the desired product and that the best yields were obtained with the fresh aerial parts of the plant. Season and area of harvesting effects have also been studied

Iridoids from Vitex cymosa

A new iridoid, named tarumal, as well as the known iridoids viteoid II and agnuside were isolated from the leaves of Vitex cymosa and identified by spectroscopic methods.

Ecdysteroids from two Brazilian Vitex species

A new ecdysteroid, 26-hydroxypinnatasterone (1), together with 20-hydroxyecdysone, was isolated from the stem barks of Vitex cymosa. 20-Hydroxyecdysone, ajugasterone C, ajugasterone C monoacetonide and turkesterone were isolated from the branches of V. polygama. The structure of 1 was determined by spectroscopic methods.

Evaluation of new polysaccharides networks for extended-release purposes: mesquite seed gum (MSG), xanthan gum and chitosan

The aim of this work was to design new hydrophilic matrix (HM) systems by cross-linking Mesquite Seed Gum (MSG), a galactomannan that occurs in the endosperm layer of the seeds of a Brazilian tree,Prosopis juliflora DC, with two well-known polysaccharides with the ability of retarding drug release, chitosan and xanthan gum. This had in mind the idea of using these new compounds in the preparation of extended-release dosage oral forms. The first part of this study was dedicated to the evaluation of MSG in terms of its functionality as a hydrophilic matrix (HM) system for extended-release purposes. Next, we started the study of water uptake profile of all polymers of interest (MSG, Xanthan Gum and Chitosan), in the following media: water, SGF and SIF. Following, we searched for the best cross-linking agent between Glutharaldehyde (GA) and Hexamethylenediisocyanate (HMDI), which turned out to be the GA. Next step we begun to prepare new hydrophilic matrices of MSG_Chitosan and MSG_Xanthan Gum, with different ratios, 1:1, 1:2 and 2:1. Finally, after deciding which new HM system presented best results, by using statistics tools, we investigated the mechanism controlling the rate release of the model drug, from tablets made with this new matrix. As a final result we concluded that the best combination of polysaccharides was achieved with MSG and Xanthan Gum, with mass ratio of 1:2, using glutharaldehyde aqueous solution as cross-linking agent. It presented a prevalent zero order kinetics, which is a very important feature when thinking about an extended-release oral dosage.

Phytochemical profile and analgesic evaluation of Vitex cymosa leaf extracts

Vitex cymosa Bertero ex Spreng., Lamiaceae, is found in Central and Amazon regions of Brazil, where it is popularly used as antirheumatic. Extracts from the leaves of V. cymosa were tested in analgesia models such as abdominal contortions induced by acetic acid and formalin to test peripheral analgesia; as well as the tail flick and hot plate models, to test spinal and supraspinal analgesia. A significant reduction was observed in the number of contortions with all extracts and in all doses. In the formalin model, a reduction in the second phase (inflammatory) was observed with all extracts, whereas only the n-butanol extract was able to act in the first, neurogenic, phase. In the tail flick model, all extracts increased latency time. Naloxone treatment reverted analgesic effect of all extracts with the exception of the dichloromethane one. All extracts developed peripheral and central analgesic activity. In the hot plate model no antinociceptive effect was observed for all tested extracts. All these results taken together suggest that V. cymosa leaf extracts were able to promote peripheral and central antinociceptive activity mediated by the opioid system.Twenty three substances were isolated and identified in the extracts and include flavonoids (C-glucosyl flavones, flavones and flavonols), triterpene acids from ursane and oleanane types, iridoids (free and glucosides), as well as simple phenols.

Structural determination Vitex cymosa Bertero active principle: Diastereoselective synthesis of (+/-)-trans-4-hydroxy-6-propyl-1-oxocyclohexan-2-one and its antinociceptive activity.

The diastereoselective synthesis of (+/-)-trans-4-hydroxy-6-propyl-1-oxocyclohexan-2-one, as a mixture trans:cis (3:1), was accomplished using a protocol that combine the Prins cyclization and RuO(4) oxidation. The synthesis this lactone allowed the elucidation of the correct structure of the substance isolated from the barks of Vitex cymosa. The delta-lactones mixture showed significant antinociceptive properties in preliminary tests using the tail flick model assay.

Avaliação da adequação técnica de indústrias de medicamentos fitoterápicos e oficinais do Estado do Rio de Janeiro

In this study we evaluated the current profile of manufacturers of officinal medicines and phytotherapeutics in relation to the Brazilian regulatory legislation. Forty-eight industries involved in manufacture and distribution of officinal medicines and phytotherapeutics were identified in one hundred current administrative processes of the National Health Surveillance Agency in Brazil. The analysis of the inspection reports of these companies considered the first nine months after the implantation of Resolution RDC 210/03 and revealed five specific company profiles: satisfactory (29.2%), satisfactory with restrictions (10.4%), unsatisfactory (6.2%), interdicted (39.6%), and applying for cancellation due to lack of conditions for complying with Resolution RDC 210/03 (14.6%). The main irregularities found in these companies involved the operational flow, quality control and product registration issues. Our results revealed a great number of companies whose activities are related to the production of officinal medicines and phytotherapeutics but that are still not totally adequate to the industrial park of Rio de Janeiro. The perspectives for the future of this category of industries are thus not favorable because of their difficulties to meet the current requirements.

Proposta de diretrizes sanitárias para avaliação do prazo de validade de saneantes com ação antimicrobiana de uso na assistência à saúde

Ate a finalizacao deste estudo, nao existia no Brasil uma legislacao no seguimento de produtos saneantes que disponibilizasse um guia cientificamente embasado para realizacao de estudos de estabilidade. O objetivo deste trabalho consiste na analise das legislacoes para registro de produtos saneantes de uso em assistencia a saude no Brasil, comparando seus diferentes criterios de estudo com legislacoes internacionais. Como resultado desta analise, propoem-se um guia para garantir a eficacia e a seguranca ao longo do prazo de validade definido para estes produtos. Verifica-se que as legislacoes internacionais estudadas apresentam criterios mais rigidos, tais como (i) a avaliacao das especificacoes de qualidade e seguranca ao longo de todo o prazo de validade proposto; (ii) a avaliacao do comportamento da embalagem e informacoes da rotulagem; (iii) o uso de uma metodologia de analise validada; (iv) e quando aplicavel um estudo que simule as variacoes do produto nas condicoes de uso (ex.: diluicoes ou ativacao para uso). Apos analise critica destas legislacoes, chega-se a proposta de um guia adequado as realidades do setor produtivo brasileiro, de forma a se regulamentar este procedimento como parte integrante do processo administrativo de registro sanitario nas rotinas da Agencia Nacional de Vigilância Sanitaria - Brasil (ANVISA).