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101.
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Liliane Bezerra de Lima Wliana Alves Viturino da Silva Ewelyn Cintya Felipe dos Santos Janaína Carla Barbosa Machado Thamara Figueiredo Procópio Maiara Celine de Moura Thiago Henrique Napoleão Magda Rhayanny Assunção Ferreira Luiz Alberto Lira Soares 《化学与生物多样性》2021,18(12):e2100538
The aim of this study was to evaluate the phytochemical composition, antioxidant, and antimicrobial potential of crude extract and fractions of Punica granatum leaves. The extract was produced by turbo extraction, after which hexanic, ethyl acetate, and aqueous fractions were obtained by partitioning. The chemical analyses were performed by thin layer chromatography and high-performance liquid chromatography, and the antioxidant activities were assayed by DPPH. and ABTS.+. Minimal inhibitory and bactericidal concentrations (MIC/MBC) were applied to twenty-two bacteria. Most strains susceptible to extract/fractions and resistant to antibiotics were selected, and ampicillin, azithromycin, ciprofloxacin, and gentamicin were associated with the ethyl acetate fraction (EAF) against multidrug-resistant strains in modulatory and checkboard models. The data from chromatographic analyses showed flavonoids and tannins in the extract, as well as the enrichment of EAF in phenols, mainly flavonoids. The flavonoids were connected to the electron transfer activity demonstrated in the DPPH. and ABTS.+ assays. Gram-positive strains are more susceptible to EAF. The subinhibitory concentrations of P. granatum enhanced the antimicrobial activity of the agents and reduced the EAF individual MIC, and the combination of EAF and antibiotics demonstrated a synergistic effect. These results present a promising approach for developing a therapy in which antioxidant extracts and fractions can be used in combination with antibiotics. 相似文献
103.
Mariana C. Pagotti Ana C. B. B. Candido Maria G. Marçal Tatiana M. Vieira Milton Groppo Márcio L. A. Silva Daniele S. Ferreira Viviane R. Esperandim Antônio E. M. Crotti Lizandra G. Magalhães 《化学与生物多样性》2021,18(12):e2100678
Despite the current treatments against Chagas Disease (CD), this vector-borne parasitic disease remains a serious public health concern. In this study, we have explored the in vitro and/or in vivo trypanocidal and cytotoxic activities of the essential oils (EOs) obtained from Dysphania ambrosioides (L.) Mosyakin & Clemants (Amaranthaceae) (DA-EO), Lippia alba (Mill.) N.E. Brown (Verbenaceae) (LA-EO), and Tetradenia riparia (Hochst.) Codd (Lamiaceae) (TR-EO) grown in Brazil Southeast. DA-EO was the most active against the trypomastigote and amastigote forms in vitro; the IC50 values were 8.7 and 12.2 μg mL−1, respectively. The EOs displayed moderate toxicity against LLCMK2 cells, but the DA-EO showed high selectivity index (SI) for trypomastigote (SI=33.2) and amastigote (SI=11.7) forms. Treatment with 20 mg/kg DA-EO, LA-EO, or TR-EO for 20 days by intraperitoneal administration reduced parasitemia by 6.36 %, 4.74 %, and 32.68 % on day 7 and by 12.04 %, 27.96 %, and 65.5 % on day 9. These results indicated that DA-EO, LA-EO, and TR-EO have promising trypanocidal potential in vitro, whereas TR-EO has also potential trypanocidal effects in vivo. 相似文献
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105.
K. A. Dutra V. Wanderley Teixeira G. S. Cruz C. T. S. Silva C. G. D´Assunção C. G. M. Ferreira 《Biotechnic & histochemistry》2013,88(7):498-513
ABSTRACTEssential oils are a promising alternative to insecticides. We investigated the LD50 of oils extracted from Piper corcovadensis, P. marginatum, and P. arboreum after 48 h topical contact with Spodoptera frugiperda larvae using morphometry, histochemistry and immunohistochemistry of the midgut and fat body. Chromatography revealed that E-caryophyllene was the principal compound common to the Piper species. The essential oils of P. corcovadensis, P. marginatum and P. arboreum caused deleterious changes in the midgut of S. frugiperda larvae. P. corcovadensis oil produced the lowest LD50 and significant histopathological alterations including elongation of the columnar cells, formation of cytoplasmic protrusions, reduction in carbohydrate, increased apoptotic index and decreased cell proliferation. P. arboreum oil caused histopathological alterations similar to P. corcovadensis, but caused the highest rate of cell proliferation and increased regenerative cells, which indicated rapid regeneration of the epithelium. Our findings demonstrated the insecticidal potential of P. corcovadensis for control of S. frugiperda owing to the significant damage it inflicted on S. frugiperda midgut. 相似文献
106.
Aquatic and riparian ecosystems are known to be highly vulnerable to invasive alien species (IAS), especially when subjected to human-induced disturbances. In the last three decades, we have witnessed a growing increase in plant invasions in Portugal and Spain (Iberian Peninsula, south-western Europe), with very detrimental economic, social and ecological effects. Some of these species, such as the giant reed (Arundo donax L.) and the water hyacinth (Eichhornia crassipes (Mart.) Solms-Laub.), number among the world's worst weeds. We present an appraisal of this invasive alien river flora and the most problematic aquatic weeds. We review various aspects of invasion ecology, including spatial and temporal patterns of invasion, species invasiveness, species traits of invasive weeds, and relationships between human disturbance in rivers and surrounding areas and invasibility, and contextualize them in overall state-of-the-art terms. We also acknowledge the use of IAS as bioindicators of the ecological quality of rivers, wetlands and riparian zones. Remote-sensing tools and Geographic Information Systems for detecting and monitoring IAS in Iberian rivers are presented. 相似文献
107.
Carmen Verissima Ferreira Eulazio Mikio Taga Hiroshi Aoyama 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):403-410
The four soybean seed acid phosphatase isoforms AP1, AP2, AP3A and AP3B were competitively inhibited by phosphate, vanadate, fluoride and molybdate, using p-nitrophenylphos-phate as substrate. The four isoforms were not significantly affected by compounds that can interact with SH residues or by pyridoxal phosphate. These results indicated that cysteine and lysine residues are not present in the active site of the four soybean seed acid phosphatase isoforms. The inhibition constant values for phosphate, vanadate, fluoride and molybdate at pH 5.0 were respectively: API (250, 12.8, 1.7, 0.05 μM), AP2 (800,10, 500, 0.025 μM), AP3A (250, 24.2,250, 0.032 μM), AP3B (2400, 36.9,750, 0.05 μM). 相似文献
108.
A. D. da Matta A. M. R. Bernardino G. A. Romeiro M. R. P. de Oliveira M. C. B. V. de Souza V. F. Ferreira 《Nucleosides, nucleotides & nucleic acids》2013,32(4):889-898
Abstract Ribosylation reactions of previously silylated 3-carbethoxy-8-methyl-1,4-dihydro-4-oxoquinoline (6a) and 3-carbethoxy-6-methyl-1,4-dihydro-4-oxoquinoline (6b) with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose (7), under Lewis acid catalysis, were studied. The method using hexamethyldisilazane (HMDS)/trimethylchlorosilane (TMCS) mixture for silylation and anhydrous stannic chloride as catalyst for ribosylation failed to give any nucleoside product. On the other hand, the protected nucleoside 3-carbethoxy-6-methyl-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-1,4-dihydro-4-oxoquinoline (8b) was obtained in good yields using bis(trimethylsilyl)trifluoroacetamide (BSTFA) containing 1% of TMCS and the same catalyst. Compound 8b was more easily isolated in higher yields with an improvement of the later method by replacing stannic chloride with trimethylsilyl trifluoromethanesulfonate (TMSOTf). De-O-benzoylation of 8b with methanolic sodium hydroxide solution afforded the free riboside 3-carbomethoxy-6-methyl-1-β-D-ribofuranosyl-1,4-dihydro-4-oxoquinoline (9b). The structures of the obtained products were confirmed by their LTV, MS, IR, 1H and 13C-NMR data. 相似文献
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110.