Miriam Machado Cunico

Anti-Helicobacter pylori activity of plant extracts traditionally used for the treatment of gastrointestinal disorders

The antibacterial activity of plant extracts obtained from Bixa orellana L., Chamomilla recutita L., Ilex paraguariensis A. St.-Hil., Malva sylvestris L., Plantago major L. and Rheum rhaponticum L. has been evaluated against two reference strains and eleven clinical isolates of Helicobacter pylori. All the plant species chosen are used in popular Brazilian cuisine and folk medicine in the treatment of gastrointestinal disorders. Initial screening was made by the disk diffusion test and then minimum inhibitory concentration was determined by the agar dilution method. The results presented in this work demonstrated that among the plant preparations analyzed, B. orellana L., C. recutita L., I. paraguariensis A. St.-Hil. and M. sylvestris L. were capable of inhibiting the in vitro growth of H. pylori.

Genotoxicity of Achillea millefolium essential oil in diploid cells of Aspergillus nidulans

The essential oil of Achillea millefolium is commonly used in folk medicine for the treatment of several diseases and has been demonstrated previously to exert an in vitro antimicrobial activity against human pathogens. Current study investigates the genotoxic activity of A. millefolium oil. The oils major constituents are: chamazulene (42.15%), sabinene (19.72%), terpin‐4‐ol (5.22%), β‐caryophyllene (4.44%) and eucalyptol (3.10%), comprising 74.63% of the total. The oils genotoxic evaluation was performed at concentrations of 0.13 µL/mL, 0.19 µL/mL and 0.25 µL/mL with a heterozygous diploid strain of Aspergillus nidulans, named A757//UT448, with green conidia. A statistically significant increasing number of yellow and white mitotic recombinants, per colony, of the diploid strain was reported after oil treatment with 0.19 µL/mL and 0.25 µL/mL concentrations. The genotoxicity of the oil was associated with the induction of mitotic non‐disjunction or crossing‐over by oil. Copyright

Termoestabilidade de processos extrativos de Nasturtium officinale R. Br., Brassicaceae por sistema Soxhlet modificado

This work had as objective verified the term-stability of the Soxhlet modified system with analytical and pharmacothecnical application in extractive processes of Nasturtium officinale. It has proven that the process is thermo-stable. The analysis with analytical have determined 3.606 mg g-1 in chlorogenic acid and 11.813 mg g-1 in rutin (extract 1:20 w/v) and with pharmacotecnical 3.427 mg g-1 in chlorogenic acid and 11.278 mg g-1 in rutin (extract 1:6 w/v). The income of the pharmacothecnical process was inferior to the analytical, suggesting that the pharmacothecnical process would need of at least the double of time in each extraction system.

Antioxidant and antibacterial activity of extracts, fractions and isolated substances from the flowers of Acacia podalyriifolia A. Cunn. ex G. Don

Os extratos e fracoes de Acacia podalyriifolia foram analisados previamente para a atividade antibacteriana atraves da difusao em disco e as propriedades antioxidantes foram verificadas pela determinacao da capacidade removedora do radical livre DPPH e pela mensuracao do conteudo de fenolicos totais (Metodo de Folin). O presente estudo descreve as atividades antibacteriana (determinacao da concentracao inibitoria minima) e antioxidante (especies reativas do acido tiobarbiturico - teste TBARS) para o extrato etanolico e as fracoes diclorometano e acetato de etila e para duas flavanonas (naringenina e 5-β-D-glicosil-naringenina) isoladas das flores de Acacia podalyriifolia A. Cunn. ex G. Don. As flavanonas naringenina e 5-β-D-glicosil-naringenina ainda nao haviam sido obtidas desta especie. A atividade antibacteriana mais efetiva foi observada com a fracao acetato de etila (CIM=0,25 mg/mL contra Staphylococcus aureus ATCC 6538; CIM=0,125 mg/mL, contra Staphylococcus epidermidis ATCC 12229; CIM=0,5 mg/mL contra Streptococcus pyogenes ATCC 19615, Klebsiella pneumoniae ATCC 13883 e Proteus mirabilis ATCC 43071). As amostras avaliadas demonstraram atividade pelo teste TBARS, especialmente o extrato etanolico (1000 ppm), que foi o mais ativo (29,43% ± 0.65), seguido pela fracao acetato de etila (1000 ppm, 24,84% ± 1,28), ambos demonstrando atividade mais elevada que a apresentada pelo acido ascorbico (1000 ppm, 21,73% ± 1,77), ainda que menor que a do BHT (1000 ppm, 35,15% ± 3,42), ambas substâncias de referencia. Naringenina e 5-β-D-glicosil-naringenina demonstraram acao antioxidante, porem somente a naringenina inibiu o crescimento de bacterias gram-positivas e gram-negativas.

Efeito alelopático e toxicidade frente à Artemia salina Leach dos extatos do fruto de Euterpe edulis Martius

Alelopatia e um processo envolvendo metabolitos secundarios produzidos por plantas que infl uenciam o crescimento e desenvolvimento de sistemas agricolas. Devido a toxicidade dos herbicidas sinteticos para o meio ambiente e para a saude humana tem-se aumentado o interesse na exploracao da alelopatia como uma alternativa para o controle de plantas daninhas. O presente trabalho avaliou efeito dos extratos dos frutos de Euterpe edulis Martius sobre o desenvolvimento de cipselas e plântulas de Lactuca sativa Linne, foram determinados o indice de velocidade de germinacao, o crescimento da radicula e do hipocotilo. Para a avaliacao da toxicidade dos extratos foi realizado o ensaio de toxicidade frente ao microcrustaceo Artemia salina Leach determinando-se a CL50 e percentual de mortalidade. A fracao remanescente demonstrou efeito alelopatico, pois todas as concentracoes alteraram os valores do indice de velocidade de germinacao e as concentracoes de 0,2 e 0,4 mg inibiram tanto o crescimento da radicula quanto o crescimento do hipocotilo. No ensaio de toxicidade todos os extratos apresentaram CL50 superior a 1000 ppm e 0% de mortalidade das artemias, indicando a nao toxicidade dos extratos.

Genotoxic activity of Eucalyptus globulus essential oil in Aspergillus nidulans diploid cells.

Eucalyptus globulus essential oil was evaluated for its genotoxic potential using a somatic segregation assay and a diploid strain of the fungus Aspergillus nidulans, heterozygous for nutritional and conidia color markers. The main compounds of the current essential oil sample were eucalyptol (49.0 %), α-pinene (8.9), β-pinene (1.5), globulol (6.9), α-eudesmol (1.12), spathulenol (1.42), γ-cadinene (1.45), trans-β-elemenone (1.23) and aromandendrene (2.3), totaling 74 % of oil. Oil at 0.12 and 0.25 μL/mL was found to increase the mitotic instability of the original diploid strain and the number of diploid mitotic recombinants of A. nidulans. The genotoxicity of the oil was associated with the induction of mitotic crossing-over or with oil-broken chromosomes.

Investigation of local anesthetic and antimycobacterial activity of Ottonia martiana Miq. (Piperaceae).

Ottonia martiana is a plant popularly known in Brazil by the use for toothache. Ethanolic extract (EE), hexane fraction (HF), dichloromethane fraction (DF) and piperovatine obtained from O. martiana were assayed in vitro and in vivo. The acute toxicity of EE was determined, and LD50 values of 164.5 and 65.0 mg/kg by the oral and intraperitoneal routes, respectively, indicated a high toxicity for EE in vivo, explaining its popular use by topical administration only. A local anesthetic-like effect of EE and its fractions was observed in experimental models using pain induction, and such effect involved an analgesic action. The antimycobacterial activity of EE, HF, DF and piperovatine was evaluated against Mycobacterium tuberculosis H37Rv ATCC 27924. EE, HF, DF, and piperovatine showed a potential antimycobacterial effect with MICs of 16.0, 62.0, 62.0 and 8.0 μg/mL, respectively. Piperovatine was more effective than the EE or the other fractions. The selectivity index (SI=IC50/MIC) values calculated for EE, HF, DF and piperovatine based on the MICs and the cytotoxicity against J774 macrophages (IC50 by MTT assay) revealed values of 6.43, 2.34, 1.5 and 9.66, respectively.

Study of vapourised solvent attack on additive manufacturing part surface

The additive manufacturing technologies has been facing an extraordinary growth during that last years, mainly as consequence of the increase of low cost FDM technologies into the marketing. In contrast with that, one of the main disadvantages of this sort of equipment is the final object finishing. For that reason, the main goal of this work is to present and characterise the post-processing which was introduced in the marketing as smoothing. In addition, a concise overview about the theory beneath this process is presented besides an experimental study that evaluates the impact of this process for the main mechanical properties of object.