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1.
J Mol Model ; 29(8): 241, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37436478

RESUMO

CONTEXT: The design and synthesis of safe and highly active sulfonylurea herbicides is still a challenge. Therefore, following some principles of structure-activity relationship (SAR) of sulfonylurea herbicides, this work focuses on evaluating two sulfonylurea derivatives bearing electron-withdrawing substituents, namely, -(CO)OCH3 and -NO2 on the aryl group, on herbicidal activity. To understand the effects caused by the substituent groups, the molecular and electronic structures of the sulfonylureas were evaluated by density functional theory. Likewise, the crystalline supramolecular arrangements of both compounds were analyzed by Hirshfeld surface, QTAIM, and NBO, with the aim of verifying changes in intermolecular interactions caused by substituent groups. Finally, through a toxicophoric analysis, we were able to predict the interacting groups in their biological target, acetolactate synthase, and verify the interactions with the binding site. METHODS: All theoretical calculations were conducted using the highly parameterized empirical exchange-correlation functional M06-2X accompanied by the diffuse and polarized basis set 6-311++G(d,p). The atomic coordinates were obtained directly from the crystalline structures, and from the energies of the frontier molecular orbitals (HOMO and LUMO), chemical descriptors were obtained that indicated the influence of the functional groups in the sulfonylureas on the reactivity of the molecules. The intermolecular interactions in the crystals were analyzed using the Hirshfeld, QTAIM, and NBO surfaces. Toxicophoric modeling was performed by the PharmaGist webserver and molecular docking calculations were performed by the GOLD 2022.1.0 software package so that the ligand was fitted to the binding site in a 10 Å sphere. For this, genetic algorithm parameters were used using the ChemPLP scoring function for docking and ASP for redocking.


Assuntos
Acetolactato Sintase , Herbicidas , Simulação de Acoplamento Molecular , Modelos Moleculares , Acetolactato Sintase/química , Acetolactato Sintase/metabolismo , Herbicidas/química , Herbicidas/farmacologia , Compostos de Sulfonilureia/química , Compostos de Sulfonilureia/farmacologia , Pirimidinas
2.
Photodiagnosis Photodyn Ther ; 43: 103654, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37308043

RESUMO

Antimicrobial photodynamic therapy (aPDT) is an alternative tool to commercial antibiotics for the inactivation of pathogenic bacteria (e.g., S. aureus). However, there is still a lack of understanding of the molecular modeling of the photosensitizers and their mechanism of action through oxidative pathways. Herein, a combined experimental and computational evaluation of curcumin as a photosensitizer against S. aureus was performed. The radical forms of keto-enol tautomers and the energies of curcumin's frontier molecular orbitals were evaluated by density functional theory (DFT) to point out the photodynamic action as well as the photobleaching process. Furthermore, the electronic transitions of curcumin keto-enol tautomers were undertaken to predict the transitions as a photosensitizer during the antibacterial photodynamic process. Moreover, molecular docking was used to evaluate the binding affinity with the S. aureus tyrosyl-tRNA synthetase as the proposed a target for curcumin. In this regard, the molecular orbital energies show that the curcumin enol form has a character of 4.5% more basic than the keto form - the enol form is a more promising electron donor than its tautomer. Curcumin is a strong electrophile, with the enol form being 4.6% more electrophilic than its keto form. In addition, the regions susceptible to nucleophilic attack and photobleaching were evaluated by the Fukui function. Regarding the docking analysis, the model suggested that four hydrogen bonds contribute to the binding energy of curcumin's interaction with the ligand binding site of S. aureus tyrosyl-tRNA synthetase. Finally, residues Tyr36, Asp40, and Asp177 contact curcumin and may contribute to orienting the curcumin in the active area. Moreover, curcumin presented a photoinactivation of 4.5 log unit corroborating the necessity of the combined action of curcumin, light, and O2 to promote the photooxidation damage of S. aureus. These computational and experimental data suggest insights regarding the mechanism of action of curcumin as a photosensitizer to inactivate S. aureus bacteria.


Assuntos
Curcumina , Staphylococcus aureus Resistente à Meticilina , Fotoquimioterapia , Tirosina-tRNA Ligase , Curcumina/farmacologia , Curcumina/química , Fármacos Fotossensibilizantes/farmacologia , Fotoquimioterapia/métodos , Staphylococcus aureus , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia
3.
Molecules ; 27(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36432059

RESUMO

Angiotensin-converting enzyme (ACE) inhibitors are one of the most active classes for cardiovascular diseases and hypertension treatment. In this regard, developing active and non-toxic ACE inhibitors is still a continuous challenge. Furthermore, the literature survey shows that oxidative stress plays a significant role in the development of hypertension. Herein, glutathione's molecular structure and supramolecular arrangements are evaluated as a potential ACE inhibitor. The tripeptide molecular modeling by density functional theory, the electronic structure by the frontier molecular orbitals, and the molecular electrostatic potential map to understand the biochemical processes inside the cell were analyzed. The supramolecular arrangements were studied by Hirshfeld surfaces, quantum theory of atoms in molecules, and natural bond orbital analyses. They showed distinct patterns of intermolecular interactions in each polymorph, as well as distinct stabilizations of these. Additionally, the molecular docking study presented the interactions between the active site residues of the ACE and glutathione via seven hydrogen bonds. The pharmacophore design indicated that the hydrogen bond acceptors are necessary for the interaction of this ligand with the binding site. The results provide useful information for the development of GSH analogs with higher ACE inhibitor activity.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Hipertensão , Humanos , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/química , Simulação de Acoplamento Molecular , Sítios de Ligação , Glutationa
4.
J Mol Model ; 28(6): 176, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35652956

RESUMO

Quinolinone-chalcones are hybrid compounds consisting of chalcone and quinolone moieties with biological activity related to their hybrid structure. This work seeks to describe the structural and theoretical parameters related to the physicochemical properties and biological activity of a new quinolinone-chalcone. The synthesis, structural characterization by X-ray diffraction, molecular topology by Hirshfeld surfaces and QTAIM, molecular electronic calculations, and pharmacophore analysis were described. The weak interactions C-H…O, C-H…π, and C-H…Br were responsible for crystal growth and stabilized the crystalline state. The DFT analysis shows that the sulfonamide group region is susceptible to observed interactions, and the frontier molecular orbitals indicate high kinetic stability. Also, pharmacophore analysis revealed potential antibacterial and herbicidal activity; by docking within the active site of TtgR, a transcription regulator for the efflux pump TtgABC from the highly resistant Pseudomonas putida (P. putida) strain DOT-TIE, we showed that the activation of TtgR relies upon the binding of aromatic-harboring compounds, which plays a crucial role in bacterial evasion. In this context, a new quinolinone-chalcone has a higher binding affinity than tetracycline, which suggests it might be a better effector for TtgR.


Assuntos
Chalcona , Chalconas , Herbicidas , Quinolonas , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Chalconas/farmacologia , Quinolonas/farmacologia , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo
5.
J Mol Model ; 27(7): 211, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34173883

RESUMO

Chalcones (E)-1,3-diphenyl-2-propene-1-ones, a class of biosynthetic precursor molecules of flavonoids, have a wide variety of biological applications. Besides the natural products, many synthetic derivatives and analogs became an object of continued interest in academia and industry. In this work, a synthesis and an extensive structural study were performed on a sulfonamide chalcone 1-Benzenesulfonyl-3-(4-bromobenzylidene)-2-(2-chlorophenyl)-2,3-dihydro-1H-quinolin-4-one with potential antineoplastic application. In addition, in silico experiments have shown that the sulfonamide chalcone fits well in the ligand-binding site of EGFR with seven µ-alkyl binding energy interactions on the ligand-binding site. Finally, the kinetic stability and the pharmacophoric analysis for EGFR indicated the necessary spatial characteristics for potential activity of sulfonamide chalcone as an antagonist.


Assuntos
Receptores ErbB/antagonistas & inibidores , Simulação de Acoplamento Molecular , Antineoplásicos/farmacologia , Relação Estrutura-Atividade
6.
Rev. bras. farmacogn ; 29(2): 162-170, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1003507

RESUMO

ABSTRACT In this work, we developed and validated a HPLC-PDA method for the quantification of hibalactone in Hydrocotyle umbellata L., Araliaceae, subterraneous parts extracts and optimized its ultrasound-assisted extraction. Chromatographic separations were carried out with an isocratic mobile phase of acetonitrile/methanol/water (10:65:25), a flow of 0.8 ml min−1, detection at 290 nm and C18 column (250 × 4.6 mm, 5 µm). The method validation parameters were determined according to Brazilian legislation. The optimization of the hibalactone ultrasound-assisted extraction was performed using Box-Behnken design and response surface methodology. The HPLC method for hibalactone quantification proved to be selective, linear, precise, accurate and robust, being useful for the analysis of hibalactone in H. umbellata subterraneous parts extracts. The optimal ultrasound-assisted extraction conditions were obtained with solid-to-liquid ratio of 1:5 g ml−1, ethanolic strength of 70% (v/v) and temperature of 65 °C. The results can provide support of the quality control and standardization of raw materials from H. umbellata.

7.
Rev. bras. farmacogn ; 28(4): 414-420, July-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-958891

RESUMO

Abstract Trembleya parviflora (D. Don) Cogn., Melastomataceae, also known as "quaresmeira-branca", is a subshrub that is commonly used to treat verminosis, scabies, dermatoses, rheumatism, vaginal infections, ulcerations and wounds. The aim of this work was to perform a morphological study of T. parviflora, evaluate the composition and chemical variability of the volatile oils from the leaves, perform phytochemical screening of the powder from the leaves and to define parameters for quality control of the plant material. Macroscopic characterization of T. parviflora was carried out by naked eye in Serra dos Pireneus, Pirenópolis, Goiás for 12 months. Volatile oils were subjected to hydrodistillation with Clevenger apparatus and analyzed by gas chromatography-mass spectrometry. Phytochemical screening and ash and volatile compound content determination were performed by conventional techniques. T. parviflora has simple, oppositely crossed and petiolate leaves. The inflorescence of this plant is a cyme. The presence of coumarins, steroids, triterpenes, flavonoids and tannins was observed. The total ash content was 4.05 ± 0.02%; the insoluble ash content was 0.10 ± 0.03%; and the volatile compound content was 9.53 ± 0.02%. The major compounds present in the volatile oils were α-terpineol (2.7-16.5%), α-pinene (0.6-25.4%), β-pinene (2.7-23.1%), sabinene (1.2-14.1%), acetoxyeudesman-4-α-ol (0.6-6.3%) and 2,4a-8,8-tetramethyldecahydrocyclopropanaphtalene (2.4-24.4). Two clusters were identified: Cluster I represented the period with low levels of rainfall, and Cluster II represented the period with high levels of rainfall. This study provides data that can be applied for the quality control of powdered leaves and is the first description of the chemical composition and variability of the volatile oils from the leaves of T. parviflora.

8.
Int. braz. j. urol ; 44(3): 624-628, May-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-954045

RESUMO

ABSTRACT Objective: To present our technique of ureteroileal bypass to treat uretero-enteric stric- tures in urinary diversion. Materials and Methods: One hundred and forty-one medical records were reviewed from patients submitted to radical cystectomy to treat muscle-invasive bladder cancer between 2013 and 2015. Twelve (8.5%) patients developed uretero-enteric anastomotic stricture during follow-up. Five patients were treated with endoscopic dilatation and double J placement. Four were treated surgically with standard terminal-lateral im- plantation. Three patients with uretero-enteric anastomotic stricture were treated at our institution by "ureteroileal bypass", one of them was treated with robotic surgery. Results: All patients had the diagnosis of uretero-enteric anastomotic stricture via computerized tomography and DTPA renal scan. Time between cystectomy and diag- nosis of uretero-enteric anastomotic stricture varied from five months to three years. Mean operative time was 120±17.9 minutes (98 to 142 min) and hospital stay was 3.3±0.62 days (3 to 4 days). Mean follow-up was 24±39.5 months (6 to 72 months). During follow-up, all patients were asymptomatic and presented improvement in ure-terohydronephrosis. Serum creatinine of all patients had been stable. Conclusions: Latero-lateral ureter re-implantation is feasible by open or even robotic surgery with positive results, reasonable operation time, and without complications.


Assuntos
Humanos , Idoso , Complicações Pós-Operatórias/cirurgia , Ureter/cirurgia , Obstrução Ureteral/cirurgia , Derivação Urinária/efeitos adversos , Bexiga Urinária/cirurgia , Íleo/cirurgia , Derivação Urinária/métodos , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Cateterismo Urinário/métodos , Cistectomia/métodos , Reprodutibilidade dos Testes , Seguimentos , Resultado do Tratamento , Constrição Patológica/cirurgia , Duração da Cirurgia , Cateteres Urinários , Tempo de Internação , Ilustração Médica
9.
Rev. bras. farmacogn ; 28(3): 303-311, May-June 2018. tab
Artigo em Inglês | LILACS | ID: biblio-958865

RESUMO

ABSTRACT Campomanesia adamantium (Cambess.) O. Berg., Myrtaceae, is a plant popularly used for its anti-inflammatory, anti-diarrhoeal and urinary antiseptic activities. The aims of this study were to obtain the crude ethanolic extract and the hexane, dichloromethane, ethyl acetate, aqueous and concentrated aqueous tannin fractions from C. adamantium leaves, perform biomonitored fractionation to isolate and identify chemical compounds, study the chemical composition of the volatile oils of the leaves and flowers and test the antimicrobial activity of the ethanolic extract, fractions, isolated substances and volatile oils. Phytochemical screening and chromatographic and spectrometric techniques were used. Volatile oils were isolated by hydrodistillation in a Clevenger apparatus and analyzed by gas chromatography/mass spectrometry. The antimicrobial activity was tested by a broth microdilution test. The component stictane-3,22-diol was isolated and identified from the hexane fraction, while valoneic and gallic acid were isolated and identified from the concentrated aqueous tannin fraction. The major constituents of the volatile oils of the leaves were verbenene (13.91%), β-funebrene (12.05%) and limonene (10.32%), while those of the volatile oils of the flowers were sabinene (20.45%), limonene (19.33%), α-thujene (8.86%) and methyl salicylate (8.66%). Antibacterial activity was verified for the hexane fraction, while antifungal activity was observed for the aqueous fraction and concentrated aqueous tannin fraction and for vanoleic acid. These results may justify the popular use of C. adamantium.

10.
An Acad Bras Cienc ; 90(2): 1565-1577, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29694495

RESUMO

Costus spiralis is a Brazilian native plant used in popular medicine, but the safety of this therapeutic use needs investigation. So, the aim of this study was to evaluate the cytogenotoxic and antigenotoxic effects of C. spiralis leaves or stems aqueous extracts on Allium cepa root cells. Moreover, a phytochemical screening and an antioxidant and antifungal activities evaluation were performed. C. spiralis aqueous extracts presented cytotoxicity, but no mutagenicity was observed. When the antigenotoxicity was evaluated, C. spiralis leaves aqueous extract presented preventive and modulatory effects on A. cepa root cells, reducing the sodium azide cytogenotoxic effects. In contrast, C. spiralis stems aqueous extract enhanced the sodium azide cytogenotoxicity in some conditions. The phytochemical screening revealed the presence of phenolic compounds in C. spiralis. When total phenolic content was determined, the leaves presented 73% more phenolic content than stems. Corroborating this data, C. spiralis leaves antioxidant potential was 30% higher than C. spiralis stems. However, these extracts did not present antifungal activity against Candida spp. In conclusion, empirical utilization of C. spiralis aqueous extracts should be avoided. Moreover, the cytotoxic effect of C. spiralis leaves and stems can play an important role in anticancer therapy and must be deeply studied.


Assuntos
Antifúngicos/farmacologia , Antioxidantes/farmacologia , Candida/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Antifúngicos/toxicidade , Antioxidantes/toxicidade , Brasil , Análise Citogenética , Dano ao DNA , Cebolas , Fitoterapia , Extratos Vegetais/toxicidade , Folhas de Planta/toxicidade , Caules de Planta/toxicidade , Testes de Toxicidade
11.
Rev. bras. farmacogn ; 28(1): 16-20, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898746

RESUMO

ABSTRACT Spiranthera odoratissima A. St.-Hil., Rutaceae, known as "manacá" is a shrub native of the Brazilian Cerrado. Their leaves and roots are popularly used to treat rheumatism, infection and abdominal pain. This study analyzed the chemical composition of volatile oils from leaves of S. odoratissima and verified the seasonal variability of its chemical composition. The volatile oils were obtained by hydrodistillation using a Clevenger type apparatus and analyzed by gas chromatography coupled to mass spectrometry. The main chemical components found in samples of volatile oils were β-caryophyllene, bicyclogermacrene, δ-cadinene, amorphous-4,7(11)-diene, α-epi-muurolol, α-cadinol, α-muurolol and γ-cadinene. The hierarchical clustering identified three groups: the first was characterized by α-epi-muurolol, the second by amorphous-4,7(11)-diene and the third group was characterized by α-muurolol. The discriminant canonical analysis was used to differentiate between clusters on the basis of oil composition. The results suggest that the rainfall presented a relationship with the chemical composition of the volatile oil. This is the first study conducted on the seasonal behavior of the chemical constituents in volatile oil from leaves of S. odoratissima.

12.
Int Braz J Urol ; 44(3): 624-628, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29211394

RESUMO

OBJECTIVE: To present our technique of ureteroileal bypass to treat uretero-enteric strictures in urinary diversion. MATERIALS AND METHODS: One hundred and forty-one medical records were reviewed from patients submitted to radical cystectomy to treat muscle-invasive bladder cancer between 2013 and 2015. Twelve (8.5%) patients developed uretero-enteric anastomotic stricture during follow-up. Five patients were treated with endoscopic dilatation and double J placement. Four were treated surgically with standard terminal-lateral implantation. Three patients with uretero-enteric anastomotic stricture were treated at our institution by "ureteroileal bypass", one of them was treated with robotic surgery. RESULTS: All patients had the diagnosis of uretero-enteric anastomotic stricture via computerized tomography and DTPA renal scan. Time between cystectomy and diagnosis of uretero-enteric anastomotic stricture varied from five months to three years. Mean operative time was 120±17.9 minutes (98 to 142 min) and hospital stay was 3.3±0.62 days (3 to 4 days). Mean follow-up was 24±39.5 months (6 to 72 months). During follow-up, all patients were asymptomatic and presented improvement in ureterohydronephrosis. Serum creatinine of all patients had been stable. CONCLUSIONS: Latero-lateral ureter re-implantation is feasible by open or even robotic surgery with positive results, reasonable operation time, and without complications.


Assuntos
Íleo/cirurgia , Complicações Pós-Operatórias/cirurgia , Ureter/cirurgia , Obstrução Ureteral/cirurgia , Bexiga Urinária/cirurgia , Derivação Urinária/efeitos adversos , Idoso , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Constrição Patológica/cirurgia , Cistectomia/métodos , Seguimentos , Humanos , Tempo de Internação , Ilustração Médica , Duração da Cirurgia , Reprodutibilidade dos Testes , Resultado do Tratamento , Cateterismo Urinário/métodos , Cateteres Urinários , Derivação Urinária/métodos
13.
Rev. bras. farmacogn ; 27(5): 663-672, Sept.-Oct. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898710

RESUMO

Abstract The Pterodon genus comprises two native species in Brazil, known as "sucupira-branca" or "faveira". Their fruits have long been used in Brazilian natural medicine, mainly for the treatment of infections and inflammations. The pharmacological properties of these fruits have often been linked with vouacapane diterpenoids. This review evaluated the scientific research in the period from 1973 to February 2017, aiming to answer how difficult it still is to develop a scientifically supported product based on Pterodon vouacapanes. Therefore, this paper reviews purification, identification, and quantification methods applied to vouacapane diterpenoids from Pterodon, as well as the performance of these phytochemicals in pharmacological tests described in the literature. Data analysis results support conventional notions that suggest vouacapane diterpenoids from Pterodon have anti-inflammatory properties. However, the studies carried out so far still represent partial assessment of the vouacapane activities and further studies need to be completed. Pterodon diterpenoids have also been associated with larvicidal, leishmanicidal, cardiovascular, and antitumor activities, which reinforces the genus' potential as a source of phytomedicines. Some remaining gaps about the reviewed activities were mentioned, while trends and perspectives for future research were proposed.

14.
Pharmacogn Mag ; 13(Suppl 2): S375-S379, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28808409

RESUMO

INTRODUCTION: The objective of this study was to compare three capsaicin extraction methods: Shoxlet, Ultrasound-assisted Extraction (UAE), and Shaker-assisted Extraction (SAE) from Habanero pepper, CNPH 15.192. MATERIALS AND METHODS: The different parameters evaluated were alcohol degree, time extraction, and solid-solvent ratio using response surface methodology (RSM). RESULTS: The three parameters found significant (p < 0.05) were for UAE and solvent concentration and extraction time for SAE. The optimum conditions for the capsaicin UAE and SAE were similar 95% alcohol degree, 30 minutes and solid-liquid ratio 2 mg/mL. The Soxhlet increased the extraction in 10-25%; however, long extraction times (45 minutes) degraded 2% capsaicin. CONCLUSION: The extraction of capsaicin was influenced by extraction method and by the operating conditions chosen. The optimized conditions provided savings of time, solvent, and herbal material. Prudent choice of the extraction method is essential to ensure optimal yield of extract, thereby making the study relevant and the knowledge gained useful for further exploitation and application of this resource. SUMMARY: Habanero pepper, line CNPH 15.192, possess capsaicin in higher levels when compared with others speciesHigher levels of ethanolic strength are more suitable to obtain a higher levels of capsaicinBox-Behnken design indicates to be useful to explore the best conditions of ultrasound assisted extraction of capsaicin. Abbreviations used: Nomenclature UAE: Ultrasound-assisted Extraction; SAE: Shaker-assisted Extraction.

15.
Rev. bras. farmacogn ; 27(4): 419-425, July-Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898684

RESUMO

ABSTRACT Trembleya phlogiformis DC., Melastomataceae, is a shrub whose leaves are used as a dye for dyeing wool and cotton. The present article aimed to carry out the morphological description of the species, to study the chemical composition of volatile oils from the leaves and flowers and the seasonal variability from the leaves during a year. Macroscopic characterization was carried out with the naked eye and with a stereoscopic microscope. Volatile oils were isolated by hydrodistillation in Clevenger apparatus and analyzed by gas chromatography/mass spectrometry. The major components of the volatile oil of T. phlogiformis flowers were: n-heneicosane (33.5%), phytol (12.3%), n-tricosane (8.4%) and linoleic acid (6.1%). It was verified the existence of a large chemical variability of the volatile oils from the leaves of T. phlogiformis over the months, with the majority compound (oleic alcohol, ranging from 5.7 to 26.8%) present in all samples. A combination of Cluster Analysis and Principal Component Analysis showed the existence of three main clusters, probably related to the seasons. The results suggested that the volatile oils of T. phlogiformis leaves possess high chemical variability, probably related to variation associated with rainfall and the variation in the behavior of specimens throughout the year. This research provides insights for future studies on the volatile oils obtained from the T. phlogiformis leaves and flowers, mainly related to biological markers of applications monitored in the leaves and flowers of this species.

16.
Rev. bras. farmacogn ; 27(4): 519-524, July-Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898696

RESUMO

ABSTRACT Obtaining artemisinin and its derivatives is very costly, which limits access to low-income people. Some hydroalcoholic extract of Artemisia annua L., Asteraceae, which has shown comparable antimalarial activity could be an alternative to the purified compound, especially if the cultivars have higher content of artemisinin. The objective of this study was to evaluate the effects of the extraction parameters (ethanol graduation, previous shaking time in an ultrasound bath and drug/solvent ratio) on the yield of artemisinin in the liquid extract obtained by percolation from A. annua and then optimize the extraction efficiency of this compound. The Box-Behnken (33) factorial design was used in association with response surface methodology. The derivatization reaction of artemisinin was used in an analytical method which was submitted to validation, after reaching the specification of the selectivity, linearity, precision, accuracy and robustness. Detection and quantification limits were 1.3 and 4.0 µg/ml, respectively. The largest amount of this compound of interest was obtained without any ultrasound bath, with an ethanol graduation of 95% and a drug/solvent ratio of 2%. Drug/solvent ratio was the factor which most influenced extraction efficiency. The maximum range of artemisinin yield was 1.21%. Information obtained in this study can be used for future approaches to determining and extracting artemisinin from A. annua.

17.
Pharmacogn Mag ; 13(50): 270-274, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28539720

RESUMO

BACKGROUND: Tithonia diversifolia belongs to the Asteraceae family. The leaves of T. diversifolia have been studied lately because of the presence of tagitinin C. OBJECTIVE: Looking for an easy and inexpensive method to extract tagitinin C from T. diversifolia leaves, this work aims to conduct a screening to evaluate the influence of different experimental factors using the dynamic maceration and ultrasound-assisted extraction methods with 23 factorial design based on response surface methodology in enhancing this chemical marker extraction. MATERIALS AND METHODS: The experimental factors were: extraction time (ET) of 30 and 60 minutes, solid: liquid ratio (SLR) of 5 and 10 grams/grams and ethanolic strength (ES) 48 and 96% (w/w). The experiments were done tripled. The content of tagitinin C in each produced extract was quantified by HPLC method. RESULTS: The highest concentrations of tagitinin C obtained under the experimental design were 0.53 mg/mL and 0.71 mg/mL, respectively for dynamic maceration (DM) and ultrasound-assisted extraction (UAE) from Tithonia diversifolia powdered leaves. For the UAE method, the main parameter for higher contents of tagitinin C was the solid: liquid ratio, followed by the ethanolic strength, and the extraction time was not significant for this method. As for the DM method, all the parameters (SLR, ES, and ET) were significant for a higher content of tagitinin C. CONCLUSION: Based on the obtained results, it was revealed that the ultrasound-assisted extraction was more effective than dynamic maceration for tagitinin C extraction from T. diversifolia powdered leaves. SUMMARY: Tithonia diversifolia leaves possess tagitinin C, a sesquiterpene lactone, as an important secondary metabolite with several biological activities, such as antimalarial, gastroprotective, chemotherapeutic adjuvants, and toxic activities.Ultrasound-assisted extraction was more effective to obtain higher levels of tagitinin C when compared with dynamic maceration extraction.Factorial design can be employed as a screening tool to find the effects of factors investigated in the extraction processes. Abbreviation used: DME: dynamic maceration extraction, UAE: ultrasound-assisted extraction, ET: extraction time, ES: ethanolic strength, SLR: solid:liquid ratio, Tag C: tagitinin C, HPLC: high-performance liquid chromatography.

18.
Rev. bras. farmacogn ; 26(6): 688-693, Nov.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-829913

RESUMO

ABSTRACT Hyptis carpinifolia Benth., Lamiaceae, is a species known popularly as "rosmaninho" and "mata-pasto", and leaves are employed in Brazilian folk medicine to treat colds, flu, and rheumatism. The aim of this study was to perform a morphological description of H. carpinifolia and to evaluate the seasonal chemical variability of the leaf essential oils during 12 months. Macroscopic characterization of H. carpinifolia was carried out with the naked eye and with a stereoscopic microscope. Essential oils were isolated from leaves by hydrodistillation in Clevenger apparatus and analyzed by gas chromatography/mass spectrometry. Major compounds were found to be 1,8-cineole (39.6-61.8%), trans-cadina-1(6),4-diene (2.8-17.5%), β-caryophyllene (4.4-10.0%), prenopsan-8-ol (4.2-9.6%) and β-pinene (2.9-5.3%). Results of essential oils compositions were processed by cluster analysis and principal component analysis. Data showed high variability in the concentration of the components. Besides, there was a seasonal variability of chemical composition, probably related mainly to the rainfall regime.

19.
Rev. bras. farmacogn ; 26(1): 23-28, Jan.-Feb. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-772633

RESUMO

Abstract Hortia oreadica Groppo, Kallunki & Pirani, Rutaceae, known as “para-tudo”, “quina”, and “quina-do-campo”, is used in traditional medicine locally to treat stomach pain and fevers. The aims of this study were: analyze the chemical composition of essential oils from leaves, flowers and fruits of H. oreadica and verify the seasonal variation of the chemical components of essential oils from leaves. The essential oils were obtained by hydrodistillation using a Clevenger type apparatus and analyzed by GC/MS. The major components found in the samples of the essential oils were the amorpha-4,7(11)-diene (29.27% – flowers, 20.26% – fruits, 27.66–37.89% – leaves), bicyclogermacrene (23.28% – flowers, 20.64% – fruits, 14.71% to 31.37% – leaves). This work represents the first study of the chemical composition of essential oils from leaves, flowers and fruits and seasonal variation in the essential oils from leaves of H. oreadica.

20.
Biotechnol Appl Biochem ; 62(6): 806-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25546578

RESUMO

The partitioning of protease expressed by Penicillium fellutanum from the Brazilian savanna in a novel inexpensive and stable aqueous two-phase system (ATPS) composed of poly(ethylene glycol) (PEG) and sodium polyacrylate (NaPA) was studied in this work using factorial design. The ATPS is formed by mixing both polymers with a salt (NaCl) and fermented broth of P. fellutanum. The effects of molar mass (2,000, 4,000, and 6,000 g ⋅ mol(-1)) and concentration (6, 8, and 10 wt%) of PEG and that of NaPA concentration (6, 8, and 10 wt%) on protease partitioning (K) at 25 °C were studied. A two-level factorial design (2(3)) was implemented. The effect of Na2 SO4 concentration (5, 10, and 15 wt%) on the reextraction of the enzyme was also analyzed. The partition coefficient K ranged from 77.51 to 1.21, indicating the versatility of the method. The reextraction was achieved with the addition of 5% Na2 SO4 , allowing the partitioning of the protease to the upper phase, whereas total proteins were directed to the bottom phase. The results of partitioning using the PEG/NaPA/NaCl system and that of the subsequent reextraction with Na2 SO4 suggest that this method can be used to purify proteases from fermented broth of P. fellutanum.


Assuntos
Resinas Acrílicas/química , Fracionamento Químico/métodos , Pradaria , Penicillium/genética , Peptídeo Hidrolases/isolamento & purificação , Polietilenoglicóis/química , Cloreto de Sódio/química , Expressão Gênica , Peptídeo Hidrolases/genética , Água/química
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