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  • Open access
  • 116 Reads
Contribution to the phytochemical study of Ocotea gardneri (MEISN) MEZ (Lauraceae).

The Lauraceae family consists of approximately 70 genera and 2,500 species, with tropical and subtropical distribution. In Brazil, it comprises 400 species distributed in 25 genera. Among these, we highlight the genus Ocotea, with about 350 species. The present work had as objective to carry out the phytochemical study of Ocotea gardneri (MEISN) MEZ. For this, the botanical material was subjected to extraction, partition and chromatographic methods for isolation of the chemical constituents. The chemical structures of the compounds were determined by spectroscopic methods and comparisons with literature models. Chromatographic fractionation of the dichloromethane phase of Ocotea gardneri resulted in the isolation of triterpene 2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexene (squalene), 3,4,5-trimethoxybenzaldehyde and the glycosylated steroid sitosterol-3-O-β-D-glucopyranoside. From the ethyl acetate phase was isolated the flavone 3, 5, 7, 3',4'-pentahydroxyflavone (quercetin) and two flavonols (-) 2- (3,4-dihydroxyphenyl) -4H-chromene-3,5,7-triol (epicatechin) and (+) 2- (3,4-dihydroxyphenyl) -4H-chromene-3,5,7-triol (catechin). All compounds are being reported for the first time in the species. Ocotea gardneri has been shown to be a promising species due to the variety of isolated chemical compounds.

  • Open access
  • 70 Reads
Chemical constituents isolated from Mandevilla dardonoi (Apocynaceae)

Mandevilla Lindl. is among the 366 genera belonging to the family Apocynaceae and has about 190 species, of which 66 are reported in Brazil. Phytochemical studies of extracts of the tuberous roots of species of this genus showed different classes of compounds, such as steroids, terpenoids and pregnane glycosides of interesting pharmacological profile, such as in vivo anti-inflammatory activity. Based on this, a phytochemical study of the roots of Mandevilla dardonoi, found in the Northeast region of the country, was carried out . The botanical material was collected in Serra do Jatobá (Serra Branca-Paraíba, 07◦29'00 ''S, 36◦39'54 "), identified by Prof. Dr. José Iranildo Miranda de Melo, Department of Biological Sciences, State University of Paraíba and deposited in the Herbarium Manuel de Arruda Câmara (exsicata number 1663). The roots were dried in an air circulation oven at an average temperature of 40 ° C, ground in a mechanical mill and subjected to maceration with 95% EtOH, giving the ethanolic extract of M. dardonoi (EEBMd-303g). The extract was partitioned and 2.8 g of the AcOEt phase were chromatographed on a silica gel 60 column, giving 32 fractions. The fractions 22-30 (35mg) were pooled and subjected to semi-preparative High Performance Liquid Chromatography (mobile phase water acidified with 0.1% formic acid / methanol), from which 6 substances were isolated. Afterwards, the data were analyzed using the following methods: ¹H-NMR (Brucker, 400 MHz, CD3OD) and Mass Spectrometry by Electrospray (Bruker, microTOF II-Ion-Trap AmazonX), which allowed the identification of 6 chlorogenic acids: 3-caffeoylquinic (3-ACQ), 4-caffeoylquinic (4-ACQ), 5-caffeoylquinic (5-ACQ), 3,4-dicaffeoylquinic 4-diACQ), 3,5- dicaffeoylquinic (3,5-diACQ) and 4,5- dicaffeoylquinic (4,5-diACQ) acids. The research contributed positively to the expansion of the knowledge about the genus Mandevilla and especially of the species M. dardonoi, which did not exist reports of phytochemical studies in the literature.

  • Open access
  • 111 Reads
Preparation of Hemissíntéticos molecular hybrids of the Diterpeno ent-7-Acetotraquiloban-18-OIC acid and its hydroxyl derivative

This work reports the isolation and structural identification of the ent-7a-acetoxi-trachyloban-18-oic acid (1) from stem of Xylopia langsdorffiana. The ent-7a-acetoxi-trachyloban-18-oic acid (1) is a secondary metabolite prevailing in this plant species, having been isolated in this work approximately 1.5 g from 2.5 kg of dry plant material. In addition to this, the compound (1) was derivatized using a modified Steglich esterification employing EDC as the coupling agent in the presence of HOBt and methyl salicylate and/or paracetamol as equivalents of alcohol in acetonitrile solution. Unfortunately, this method did not provide the expected molecular hybrids. Despite this, it was possible to isolate and identify by this approach the unpublished semisynthetic derivative trachylobane-benzotriazole (4). These compounds were identified by Nuclear Magnetic Ressonance-NMR, IR and by comparison of the obtained data with that described in the literature.

  • Open access
  • 142 Reads
Phytochemical research of Cordia rufescens A.DC

Cordia rufescens A. DC, a small shrub in northeastern Brazil is popularly referred to as "old-growth" or "pigeon-claw". This plant is used in folk medicine as abortive, anti-inflammatory agent and in the treatment of dysmenorrhea and dyspesia (VALE et al., 2012). Thus, the need for a greater chemical and pharmacological knowledge of Cordia rufescens A.DC species was observed, necessitating a more in-depth study of the isolation and characterization of new compounds. The plant material (leaves) was collected in 2002 in the municipality of Cruz do Espírito Santo - PB and identified by Profa. Dr. Maria de Fátima Agra. The material was then oven dried with circulating air at an average temperature of 45 ° C, ground in a mechanical mill and subjected to steeping with 95% EtOH. The crude ethanolic extract (106.10 g) was dissolved in a methanol: water (7: 3 v / v) solution and partitioned with the following solvents: hexane, dichloromethane and ethyl acetate. An aliquot of the dichloromethane phase (7 g) was subjected to the chromatographic column (CC), using as a stationary phase silica gel, and as mobile phase hexane, ethyl acetate and methanol, with elution systems in increasing polarity order, obtaining 34 fractions. All fractions were submitted to analytical thin layer chromatography (ADCC) and analyzed and assembled according to their retention factors (Rfs) and after visualization in ultraviolet light. Fractions 2, 3 and 5 presented different retention factors and therefore were submitted to liquid chromatography of high efficiency in analytical scale, where fraction 5 was chosen to obtain a better resolution of the chromatogram in front of the others, being then submitted to the purification by HPLC on a semi-preparative scale that resulted in the identified substances 4-hydroxy-benzaldeído and 4 -hydroxy-3,5-dimethoxycinnamate, reported for the first time in the species under study.

  • Open access
  • 164 Reads
Chemometrics and Molecular Modeling applied to coumarin derivatives as potential multitarget inhibitors in Mycobacterium tuberculosis

Tuberculosis (TB) is still a worldwide health problem caused, in large part, by mycobacterium tuberculosis (MTB). The urgent need for the discovery of new antitubercular (anti-TB) agents has revealed the activity of coumarin derivatives against MTB. Therefore, a serie of 36 coumarins derivates was used to evaluated their antitubercular activity in silico against three proteins of Mycobacterium tuberculosis, known as FadD32, wild type and mutant DNA gyrase. The compounds had their energies minimized. Calculations of molecular descriptors were performed to carry out chemometric study of CPCA, docking and molecular dynamics. Our results showed that the major influence is the amphiphilic character, with predominance of the hydrophilic character, which corroborated with the docking results in the cavity of the active site for proteins. In homology studies it has been observed that mutation changes contribute to protein destabilization and may interfere with compound activity. The Score values and the interactions for the three proteins of the study were also favorable, evidencing the promising activity of coumarins derivatives antitb. We observed that the greatest divergence of interactions occurred for GyrA, whereas for GyrB the mutations did not influence the interaction of coumarins. In molecular dynamics studies showed similar degree of instability the ligand pdb and coumarin, showing that certain residues are involved in the conformational alteration of the protein. Therefore, we conclude that the lead compound 2c showed potentiality of the coumarin derivative class as new candidate antituberculosis.

  • Open access
  • 314 Reads
CHEMISTRY OF ARBORININE AND PHARMACOLOGICAL ACTIVITIES

Arborinine is an acridone alkaloids obtained from different natural sources including in the majority bark, seed, leaves of plants species of Rutaceae family among which Teclea gerrardii, Zanthoxylum leprieurii and Teclea trichocarpa, Erthela bahiensis, Ruta angustifolia,, Ruta suavolenses.. This alkaloid is extensively studied due to its great pharmacological potential, which includes anticancer, antimicrobial, antiparasitic, antifeedant and antioxidant activities among others. Arborinine block heme-mediated protein oxidation and degradation markers for heme-induced oxidative stress; was predicted virtually for a critical evaluation by In silico target fishing for rationalized ligand discovery by inhibiting acetylchlolinesterase with IC50 value 34.7 ± 71µM; displayed potent in vitro activities against chloroquine sensitive HB3 cell line and chloroquine resistance K1 cell line with IC50 value 3.85 ± 0.11μM and 9.34 ± 0.37 μM; showed the good anticancer activity on three human cancer line viz human colon cancer COLO-205, human ovarian cancer OVCAR-3, Human cervical cancer human breast cancer and T-47D line with GI50 value ˂10μg/ml and presented antimicrobial activities against resistant microbial strains. The overall synthesis of Arborinine has been done and the key stapes are the Ullmann condensation followed by the cyclisation with Eaton’s reagent. It undergoes a few structural modification reactions such as selective methylation and demethylation, electrophilic substitution. Acetylation, benzoylation. This review present the chemistry and the biological properties of Arborinine: methods of isolation from plant crude extract, its characterization as well as their derivatives obtained by structural modification including structure activity relationship are also described.

  • Open access
  • 134 Reads
Antimalarial acridine N-acylidrazonic derivatives: ADME in silico studies and molecular

Malaria is one of the neglected diseases, and according to WHO it affects approximately 214 million people around the world. In addition to being an aggressive disease, the drugs used are scarce, have severe adverse effects and are often ineffective due to the development of parasite resistance mechanisms. In addition to these factors, difficulties in P&D of new drugs, due to pharmacokinetic and bioavailability limitations of antimalarial candidates, are difficult for the development of therapeutically useful new drugs. In this context, this work was aimed at using in silico studies of ADMET and molecular docking to predict pharmacokinetic parameters, and the interaction of acridine derivatives with the enzyme Dihydrofolate reductase (DHFR-TS) of P.falciparum. For the ADMET study was using the SwissADME free software. For the docking, the enzyme PfDHFR-TS (PDB code id: 4DPD) was chosen, and the acridine derivatives published in the paper by PEREIRA (2016) were used as binders. Molecular docking was performed by the Moqueiro Virtual Docking 6.0 program, in which the protein was optimized and the compounds were submitted to molecular coupling after optimization of the geometry. The results indicate that all derivatives have desirable molecular properties for a new drug, as well as indicate good gastrointestinal absorption (TPSA ≤ 140 Å2) and bioavailability. The molecules studied have the potential to inhibit the CYP2C19, CYP2C9 and CYP3A4 isoforms, however, none of them possibly interact with the P-gp protein. Molecular docking results indicate that all compounds showed negative binding energy, with AC-10 being the best result, indicating the possibility of stable interactions with the enzyme PfDHFR-TS, which is responsible for the resistance of P. falciparum to many antiamalarials agents.

  • Open access
  • 104 Reads
Chemical characterization and antimicrobial activity of the essential oil from Leptohyptis macrostachys (Benth.)Harley & J.F.B. Pastore

The Lamiaceae family has approximately 300 genera and 7,500 species and it is estimated that at least 22 genera and 402 species. Leptohyptis macrostachys(Benth.) Harley & J.F.B. Pastore is a shrub species belonging to the family Lamiaceae, found in the semi-arid region of northeastern Brazil and popularly known as "alfavaca-brava" and "hortelã-do-mato". In this study, a chemical characterization of L. macrostachysessential oil was carried out. The plant material was collected in the city of Serra Branca, Paraíba, in northeastern Brazil. The essential oil from L. macrostachyswas obtained by the hydrodistillation process. The chemical characterization of the essential oil was performed by a gas chromatograph coupled to a mass spectrometer (GC-MS). An analysis of the antimicrobial activity of the essential oil was carried out using the broth microdilution method to determine the Minimum Inhibitory Concentration (MIC), using Escherichia coli, Salmonella enteritidis, Staphylococcus aureus, S. epidermidis, Candida albicans, C. tropicalisand Cryptococcus neoformansstrains. The investigation of the essential oil from L. macrostachysby GC-MS allowed the identification of 43 components, corresponding to 99% of the total oil. The major constituents were Fenchone (20.14%), 1,8-cineole (19.74%), β-pinene (12.31%), Germacrene D (7.14%), Limonene (6,74 %), α-pinene (4.74%) and Thymol (4.52%). In relation to the antimicrobial activity, the essential oil from L. macrostachyspresented a strong activity, being able to inhibit bacterial and yeast growth in concentrations below 600 μg/mL. Among the bacterial strains, the essential oil showed a greater activity against the gram-positive strains and among the microorganisms used in this study, the essential oil presented higher potency against yeasts than against bacteria strains.

  • Open access
  • 84 Reads
Efeito adjuvante de Zingiber Officinale L. em pacientes com câncer

The Zingiber officinale popularly known as ginger or mangarataia, since antiquities is widely used for therapeutic and culinary purposes. Popularly used in infusions against colds, juices with fruits, in cooking in crystallized pieces, dehydrated, dried or powdered. The objective of this study is to discuss the use of the same as an adjuvant treatment in the control of emesis and nausea of ​​cancer patients under treatment. The mechanism of action of ginger responsible for the antiemetic activity, is not yet clear. Ginger has volatile oils, such as shogaol and gingerol which are its active chemical constituents. Studies in rats showed direct effect on the gastrointestinal tract and action on the Central Nervous System. Emesis and nausea are the main effects induced by cytotoxic drugs. According to reports in the literature, ginger has a promising antiemetic action as adjuvant therapy in cancer patients, bringing about the reduction of these symptoms and still acting with other beneficial effects such as anti-inflammatory, antioxidant, antimicrobial, anticoagulant, hypolipidemic and hypoglycemic. Its ideal use is in therapeutic doses recommended according to each patient profile and for limited periods, it would also enable the reduction of other conventional drugs, both the use of several drugs by the patient, as well as bring positive financial reflexes for the company. From this study we can observe the beneficial action of the use of medicinal plants, and may also emphasize the importance of investing in further studies and clinical trials, since there is no ginger-based medicine on the market.

  • Open access
  • 84 Reads
Phytochemistry and anticancer potential of graviola (Annona muricata)

Cancer is an invasive proliferative disease that is ranked among death leaders
worldwide. There is a need in prospecting for novel therapeutic molecules, as
well as the formulation of more effective chemotherapeutics. Since more than
40% of antineoplastics are derivative from natural products, the latter and their
synthetic analogues have been widely used in this process, starting from simple
to complex molecules, promoting specific target molecule targeting. The use of
folk medicine helped in the discovery of a class with anticancer potential:
acetogenin (AG). AG belong to the class of polyketides, present in the family
Annonaceae. Thus, the objective of the present study was to carry out a review
of prospective literature on the use of graviola (Annona muricata) with antitumor
activity and future perspectives as chemotherapeutic. The review was
conducted through the Medline/PubMed and Science Direct databases,
selecting scientific articles on the subject, characterizing the literature review.
The graviola has a quantity greater than 70 acetogenins (AG) that are
distributed in the stem, leaves and seeds. AG has been shown to participate in
the process of inducing death in tumor cells resistant to other chemotherapeutic
agents. Many AG derivatives have shown toxicity against cancer cells, including
multiple drug resistant (MDR) strains. Bullatacin, another type of AG, also
showed marked antitumor activity against mammary cells with multiple drug
resistance (MDR) phenotype. Another significant work demonstrated the
participation of graviola AG in tumor cytotoxicity through inhibition of the
mitochondrial complex, which is involved in oxidative phosphorylation and ATP
synthesis. Furthermore, AG promotes apoptosis of breast tumor cells. Thus, the
pharmaceutical technology in the formulation of AG as a chemotherapeutic
reveals a promising future in cancer treatment, especially the types that present
the MDR phenotype, the biggest obstacle in cancer treatment.

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