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1.
Sci Rep ; 11(1): 6854, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767225

RESUMO

Colorectal cancer (CRC) represents the third leading cause of death among cancer patients below the age of 50, necessitating improved treatment and prevention initiatives. A crude methanol extract from the wood pulp of Artocarpus heterophyllus was found to be the most bioactive among multiple others, and an enriched extract containing 84% (w/v) artocarpin (determined by HPLC-MS-DAD) was prepared. The enriched extract irreversibly inhibited the activity of human cytochrome P450 CYP2C9, an enzyme previously shown to be overexpressed in CRC models. In vitro evaluations on heterologously expressed microsomes, revealed irreversible inhibitory kinetics with an IC50 value of 0.46 µg/mL. Time- and concentration-dependent cytotoxicity was observed on human cancerous HCT116 cells with an IC50 value of 4.23 mg/L in 72 h. We then employed the azoxymethane (AOM)/dextran sodium sulfate (DSS) colitis-induced model in C57BL/6 mice, which revealed that the enriched extract suppressed tumor multiplicity, reduced the protein expression of proliferating cell nuclear antigen, and attenuated the gene expression of proinflammatory cytokines (Il-6 and Ifn-γ) and protumorigenic markers (Pcna, Axin2, Vegf, and Myc). The extract significantly (p = 0.03) attenuated (threefold) the gene expression of murine Cyp2c37, an enzyme homologous to the human CYP2C9 enzyme. These promising chemopreventive, cytotoxic, anticancer and anti-inflammatory responses, combined with an absence of toxicity, validate further evaluation of A. heterophyllus extract as a therapeutic agent.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Artocarpus/química , Colite/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Extratos Vegetais/farmacologia , Madeira/química , Animais , Azoximetano/toxicidade , Colite/induzido quimicamente , Colite/patologia , Neoplasias Colorretais/patologia , Citocromo P-450 CYP2C9/química , Citocromo P-450 CYP2C9/metabolismo , Células HCT116 , Humanos , Masculino , Lectinas de Ligação a Manose/química , Camundongos , Camundongos Endogâmicos C57BL , Lectinas de Plantas/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-33133220

RESUMO

Desmodium canum (Strong back) commonly consumed as a tea or tonic is believed to possess hypoglycaemic activity. This paper sets out to isolate potential hypoglycaemic compounds present within the plant and investigate their synergistic effects on blood glucose levels in euglycaemic Sprague Dawley rats. The milled plant was sequentially extracted using hexane, ethyl acetate and methanol. The ethyl acetate extract was subjected to column chromatography yielding seven major fractions and were subsequently bioassayed using the Oral Glucose Tolerance Test (OGTT). Further chromatographic separation and analysis using Gas Chromatography-Mass Spectroscopy and Fourier Transform Infrared Spectroscopy enabled the identification of two hypoglycaemic compounds, oleic acid (OA) and succinic acid (SA). These were bioassayed individually and as a cocktail to determine the synergistic effects using OGTT. Intravenous administration of these compounds individually indicated both are very potent in retarding blood glucose levels. However, the most significant activity was observed on synergistic administration. The cocktail (1 : 1) displayed significant hypoglycaemic activity throughout the entire study. It also significantly differed from OA at the 120 min interval (3.43 ± 0.22 mmol/L vs. 4.98 ± 0.19 mmol/L, resp., p=4.29 × 10-7) and significantly differed from SA at 30 min (3.95 ± 0.43 mmol/L vs. 5.17 ± 0.32 mmol/L, resp., p=0.003), 90 min (4.35 ± 0.36 mmol/L vs. 5.49 ± 0.69 mmol/L, resp., p=0.04), and 120 min intervals (3.43 ± 0.22 mmol/L vs. 4.94 ± 0.31, resp., p=1.54 × 10-5). Oral administration of the cocktail showed comparable potency to that of metformin (p > 0.05) throughout the OGTT curve. The synergistic effects of the naturally isolated compounds yielded higher potency levels than individual administration and when administered orally, the hypoglycaemic effect was similar to that of metformin. This may assist in paving a way to attempt a novel method in approaching antidiabetic therapy.

3.
Fitoterapia ; 129: 191-197, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29981873

RESUMO

Cleome rutidosperma DC, commonly known in Jamaica as 'consumption-weed' is a plant traditionally used in folklore for treating tuberculosis and other infectious and chronic ailments. We evaluate for the first time the chemical composition and biological activities of the essential oil components of the complete aerial parts of this plant. The essential oil obtained by steam distillation (0.02%) was analyzed by a combination of gas chromatography-flame ionization detector (GC-FID), gas chromatography-mass spectroscopy (GC-MS) and retention index (RI). The volatile oil of C. rutidosperma was dominated by oxygenated diterpenes (67.6%); with (Z)-phytol (65.1%) being the single most abundant constituent. C. rutidosperma aerial essential oil exhibited moderate inhibition against the activity of recombinant arylamine N-acetyltransferase (NAT) from Mycobacterium marinum (IC50 22.20 ±â€¯1.80 µg/µL), while, racemic phytol had an inhibition with an IC50 of 22.33 µg/µL ±â€¯0.50 µg/µL, thus accounting for the NAT inhibition imparted by the crude oil. Inhibition of NAT, a key enzyme in mycobacterial growth may be the pathway in which phytol, shown in this study to interact with the active site using in-silico methods, renders its previously demonstrated anti-tubercular properties. The phytol rich essential oil also demonstrated antimicrobial activity against all nine human pathogenic bacteria and the fungus strain assayed, with the most significant inhibitory activity against Bacillus cereus and justifies the need for further evaluation and development of the essential oils from this plant.


Assuntos
Cleome/química , Óleos Voláteis/química , Óleos de Plantas/química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Jamaica , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia
4.
Molecules ; 23(2)2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29462868

RESUMO

Understanding the potential for adverse drug reactions (ADRs), from herb-drug interactions, is a key aspect of medicinal plant safety, with particular relevance for public health in countries where medicinal plant use is highly prevalent. We undertook an in-depth assessment of extracts of Hyptis verticillata Jacq., via its impact on activities of key cytochrome P450 (CYP) enzymes (CYPs 1A1, 1A2, 1B1, 3A4 and 2D6), its antioxidant properties (determined by DPPH assays) and chemical characterisation (using LC-MS). The dried plant aqueous extract demonstrated potent inhibition of the activities of CYPs 1A1 (7.6 µg/mL), 1A2 (1.9 µg/mL), 1B1 (9.4 µg/mL) and 3A4 (6.8 µg/mL). Further analysis of other crude extracts demonstrated potent inhibition of CYP1A2 activity for a dried plant ethanol extract (1.5 µg/mL), fresh plant ethanol extract (3.9 µg/mL), and moderate activity for a fresh plant aqueous extract (27.8 µg/mL). All four extracts demonstrated strong antioxidant activity, compared to the positive control (ascorbic acid, 1.3 µg/mL), with the dried plant ethanol extract being the most potent (1.6 µg/mL). Analysis of the dried plant aqueous extract confirmed the identity of seven phytochemicals, five lignans and two triterpenes. Individual screening of these phytochemicals against the activity of CYP1A2 identified yatein as a moderate inhibitor (71.9 µM), likely to contribute to the plant extract's potent bioactivity. Further analysis on the impact of this plant on key drug metabolizing enzymes in vivo appears warranted for likely ADRs, as well as furthering development as a potential chemopreventive agent.


Assuntos
Inibidores das Enzimas do Citocromo P-450/química , Hyptis/química , Extratos Vegetais/química , Citocromo P-450 CYP1A2/efeitos dos fármacos , Inibidores das Enzimas do Citocromo P-450/farmacologia , Interações Ervas-Drogas , Humanos , Extratos Vegetais/farmacologia
6.
Nat Prod Commun ; 7(9): 1231-2, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23074917

RESUMO

The chemical composition of the essential oil obtained from the aerial parts of Cleome serrata by hydrodistillation was analyzed by employing GC-FID, GC-MS and RI. Fourteen compounds comprising 90.4% of the total oil composition were characterized. The main components identified were (Z)-phytol (53.0%) and di(2-ethylhexyl)-phthalate (DEHP) (14.7%). The oil was evaluated for its in vitro antimicrobial activities against nine pathogenic microorganisms using the filter paper disc diffusion method. Moderate antimicrobial activity was observed against five of the pathogens assayed. In addition, the essential oil was tested against the sweet potato weevil, Cylas formicarius elegantulus. Strong knockdown insecticidal activity was observed.


Assuntos
Cleome/química , Óleos Voláteis/análise , Bactérias/efeitos dos fármacos , Jamaica , Óleos Voláteis/farmacologia
7.
Nat Prod Commun ; 6(11): 1775-96, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22224308

RESUMO

Several species belonging to the Hyptis (Lamiaceae) genus represent an important source of bioactive constituents, which are reputed for their wide range of antimicrobial, anticancer and insecticidal activities. The volatile oils obtained from various parts of the Hyptis plants were found to be primarily composed of mono- and sesquiterpenes. Significant differences were observed in the percentage compositions of the major components, which allowed for differentiation among the species. Based on the dominant constituents, phylogenetic relationships were found to be common among some species: 1,8-cineole (H. fruticosa, H. goyazensis, H. martiusii and H. suaveolens); beta-caryophyllene (H. marrubioides, H. pectinata, H. spicigera and H. suaveolens); eugenol (H. recurvata and H. suaveolens); gamma-cadinene (H. glomerata and H. ovalifolia); p-cymene (H. mutabilis and H. pectinata); alpha-pinene (H. crenata and H. emoryi). The monoterpenes, alpha-pinene and p-cymene were detected at various concentrations in all the Hyptis oils investigated. This paper reviews the essential oil compositions of eighteen Hyptis plant species studied in various parts of the world covering the publications of 100 years (1909 to 2009) after the first article appeared in the literature.


Assuntos
Hyptis/química , Óleos Voláteis/química , Especificidade da Espécie
8.
Nat Prod Commun ; 5(8): 1301-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20839641

RESUMO

Five different essential oil extractions of the aerial parts of Cleome spinosa Jacq. were examined. The oils obtained by hydrodistillation of the whole aerial parts, aerial parts without flowers (fruit, leaves and stem), flowers, fruits and leaves have been examined by GC-FID and GC-MS. The chemical profiles of the oils reveal the dominance of oxygenated sesqui- and diterpenes, with the exception of the fruit oil, which contained a high content of fatty acids. The most abundant compounds from the whole aerial parts were (Z)-phytol (31.3%), integerrimine (5.5%) and incensole (4.0%). The major compounds from the aerial portion without flowers were caryophyllene oxide (10.5%), (-)-spathulenol (7.5%) and Z-phytol (6.9%). In the flower oil, the main components were 7-alpha-hydroxy manool (23.8%), incensole (9.2%) and sclareol (8.7%). The chief constituents in the fruit oil were tetradecanoic acid (40.6%), (Z)-phytol (6.58%) and sclareol (4.5%). In the leaf oil, (Z)-phytol (19.5%), 7-alpha-hydroxy manool (6.8%) and caryophyllene oxide (4.36%) were the predominant compounds. Antimicrobial activity of the oil obtained from the whole aerial part was evaluated against nine microbial strains using a filter paper disc-diffusion method. The volatile oil showed moderate action against seven of the eight bacteria strains used, with significant inhibitory activity against Streptococcus pyogenes Group A when compared with the standard antibiotics, ampicillin and gentamicin. The fungus, Candida albicans was less sensitive to the essential oil. The oils showed moderate insecticidal activity against Cylas formicarius elegantalus, but possessed no antioxidant activity as indicated by the DPPH method. This represents the first report on the chemical composition of the essential oils from C. spinosa found in Jamaica and the in vitro antioxidant, insecticidal and antimicrobial potential of the oil from the aerial parts.


Assuntos
Anti-Infecciosos/farmacologia , Cleome/química , Óleos Voláteis/análise , Animais , Antioxidantes/farmacologia , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Gorgulhos
9.
Nat Prod Commun ; 4(3): 307-10, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19413104

RESUMO

From the methanolic extract of the plant Hyptis verticillata Jacq, was isolated five compounds: the novel compounds cadina-10(15)-en-3-one and 3,7,11,15-tetramethylhexadec-1-en-3-ol and the known compounds 3,7,11,15-tetramethylhexadec-2-en-1-ol, 7,11,15-trimethyl-3-methylenehexadecane-1,2-diol and myo-inositol. All structures were established by spectroscopic means.


Assuntos
Diterpenos/análise , Diterpenos/isolamento & purificação , Hidrocarbonetos Acíclicos/análise , Hidrocarbonetos Acíclicos/isolamento & purificação , Hyptis/química , Sesquiterpenos/análise , Sesquiterpenos/isolamento & purificação , Jamaica , Espectroscopia de Ressonância Magnética , Metanol , Estrutura Molecular
10.
Nat Prod Commun ; 4(1): 15-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19370867

RESUMO

Seven abietane diterpenoids were isolated from the roots of Hyptis verticillata (Labiatae). One is a novel natural product, 7-acetoxy-16-benzoxy-12-hydroxyabieta-8,12-diene-11,14-dione (1), while the other six known compounds are 11,14 dihydroxy-12-methoxyabieta-8,11,13-triene-7-one (2), 11,14-dihydroxy-12-methoxy- 18(4-->3betaH) abeo-abieta-4(19),8,11,13-tetraene-7-one (3), 7-acetoxy-12-methoxyabieta-8,12-diene-11,14-dione (4), royleanone (5), 7,6-dehydroroyleanone (6) and 7-acetoxyhorminone (7). All structures were elucidated by spectroscopic and mass spectrometric means.


Assuntos
Abietanos/química , Hyptis/química , Modelos Moleculares , Estrutura Molecular , Raízes de Plantas/química
11.
J Agric Food Chem ; 53(12): 4774-7, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15941314

RESUMO

The chemical composition of the essential oil obtained by hydrodistillation from the aerial parts of Hyptis verticillata Jacq. was elucidated by a combination of GC and GC-MS analyses. The oil was dominated by the sesquiterpenoids cadina-4,10(15)-dien-3-one (15.1%) (1) and aromadendr-1(10)-en-9-one (squamulosone) (30.7%) (2). The oil exhibited chemosterilant activities against the cattle tick, Boophilus microplus Canest., and toxic action against adult Cylas formicarius elegantulus Summer, the most destructive pest of sweet potato (Ipomoea species).


Assuntos
Hyptis/química , Inseticidas , Óleos Voláteis/química , Animais , Cromatografia Gasosa , Besouros , Cromatografia Gasosa-Espectrometria de Massas , Ixodidae
12.
Acta Crystallogr C ; 60(Pt 11): o798-800, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15528823

RESUMO

Mikanolide [systematic names: 1,10:2,3-diepoxy-6,8-dihydroxy-11-vinylgermacr-4-ene 12,14-di-gamma-lactone and 7,10a-dimethyl-1a,1b,2a,6a,7,9a,10,10a-octahydro-4H-6,3-methenofuro[3,2-c]bisoxireno[f,h]oxacycloundecin-4,8(6H)-dione], C(15)H(14)O(6), derived from a variety of Mikania micrantha growing in Portland, Jamaica, contains a methylcyclodecane ring fused to an unsaturated planar alpha,gamma-lactone, an envelope-type near-planar vinyl-beta,gamma-lactone and two epoxide moieties. The crystal packing shows stacks of mikanolide molecules interlocked via a network of non-classical C-H...O hydrogen bonds between the lactone units.


Assuntos
Estrona/análogos & derivados , Estrona/química , Lactonas/química , Mikania/química , Anti-Infecciosos/química , Antineoplásicos Fitogênicos/química , Cristalografia por Raios X , Ligação de Hidrogênio , Jamaica , Modelos Moleculares , Conformação Molecular , Sesquiterpenos de Germacrano
13.
Talanta ; 62(4): 781-9, 2004 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-18969363

RESUMO

The compound di-2-thienyl ketone p-nitrophenylhydrazone (DSKNPH) melting point 168-170 degrees C was isolated in good yield from the reaction between di-2-thienyl ketone (DSK) and p-nitrophenylhydrazine in refluxing ethanol containing a few drop of concentrated HCl. Nuclear magnetic resonance studies on DSKNPH in non-aqueous solvents revealed strong solvent and temperature dependence due to solvent-solute interactions. Optical measurements on DSKNPH in DMSO in the presence and absence of KPF(6) gave extinction coefficients of 83,300+/-2000 and 25,600+/-2000M(-1)cm(-1) at 612 and 427nm at 295K. In CH(2)Cl(2), extinction coefficient of 34,000+/-2000M(-1)cm(-1) was calculated at 422nm. When DMSO solutions of DSKNPH were allowed to interact with DMSO solutions of NaBH(4) the low energy electronic state becomes favorable and when DMSO solutions of DSPKNPH where allowed to interact with DMSO solutions of KPF(6) or NaBF(4), the high energy electronic state becomes favorable. The reversible BH(4)(-)/BF(4)(-) interconversion points to physical interactions between these species and DSKNPH and hints to the possible use of DSKNPH as a spectrophotometric sensor for a variety of physical and chemical stimuli. Thermo-optical measurements on DSKNPH in DMSO confirmed the reversible interconversion between the high and low energy electronic states of DSKNPH and allowed for the calculations of the thermodynamic activation parameters of DSKNPH. Changes in enthalpy (DeltaH(slashed circle)) of +57.67+/-4.20; 27.15+/-0.90kJmol(-1), entropy (DeltaS(slashed circle)) of +160+/-12.88; 83+/-2.91Jmol(-1) and free energy (DeltaG(slashed circle)) of -8.52+/-0.40; 2.66+/-0.25kJmol(-1) were calculated at 295K in the absence and presence of NaBH(4), respectively. Manipulation of the equilibrium distribution of the high and low energy electronic states of DSKNPH allowed for the use of these systems (DSKNPH and surrounding solvent molecules) as molecular sensors for group I and II metal ions. Group I and II metal ions in concentrations as low as 1.00x10(-5) M can be detected and determined using DSKNPH in DMSO.

15.
J Pharm Pharmacol ; 51(12): 1455-60, Dec. 1999.
Artigo em Inglês | MedCarib | ID: med-865

RESUMO

We have started a systematic scientific study of folklore medicinal plants currently used as alternative medicine in Jamaican society. In this initial study, extracts of plants widely used by the islanders are studied for antibacterial activity against five common pathogens; Streptococcus group A, Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa and Escherichia coli. These studies revealed that 25 percent (approximately) of the plant extracts had antimicrobial activity against at least one of the microbes used. Subsequent to these observations, extracts from Mikania micrantha were examined in detail. This led to the isolation of two sesquiterpenoids, mikanolide and dihydromikanolide, with activity against S. aureus and C. albicans. The results suggest that traditional folk medicine could be used as a guide in our continuing search for new natural products with potential medicinal properties.(Au)


Assuntos
Anti-Infecciosos/farmacocinética , Bactérias/efeitos dos fármacos , Extratos Vegetais/farmacocinética , Plantas Medicinais/química , Jamaica , Anti-Infecciosos/química , Bactérias/isolamento & purificação , Medicina Tradicional , Extratos Vegetais/química
16.
New York; W.W. Norton & Company; 1999. 831 p.
Monografia em Inglês | HISA - História da Saúde | ID: his-6251
17.
In. Porter, Roy. The greatest benefit to mankind: a medical history of humanity. New York, W.W. Norton & Company, 1997. p.462-491.
Monografia em Inglês | HISA - História da Saúde | ID: his-9245

RESUMO

It approaches the distinctive tropical medicine that arose in the last third of the nineteenth century, supplanting the traditional ´medicine of warm climates´.(AU)


Assuntos
Medicina Tropical/história , Doenças Endêmicas/história , História da Medicina , Zona Tropical
18.
Phytochemistry ; 40(2): 735-38, Oct. 1995.
Artigo em Inglês | MedCarib | ID: med-4589

RESUMO

The novel assingment of 13C and 1HNMR data for cadina-4,10(15)-dien-3-one obtained from Hyptis verticillata is presented. The study revealed that cadina-4,10(15)-dien-3-one possesses chemosterilant activities against the economically important cattle tick, Boophilus microplus, and toxic action against adult Cylas formicarius the most destructive pest of sweet potato (I pomoea sp.) (AU)


Assuntos
21003 , Feminino , Masculino , Besouros , Inseticidas , Naftalenos/química , Carrapatos , Isótopos de Carbono , Bovinos , Hidrogênio , Estrutura Molecular , Naftalenos/isolamento & purificação , Naftalenos/toxicidade , Espectroscopia de Ressonância Magnética , Plantas
20.
London; Routledge; 1993. 2v p.
Monografia em Inglês | HISA - História da Saúde | ID: his-4354

RESUMO

If medicine forms the core of this volume, it is medicine in the broadest sense, encompassing understanding of the body in sickness and in health, the parts played by morbidity and mortality in shaping human destines, the multiform interactions between patients, doctors, medical institutions, and the wider world. " The art has three factors:' judged Hippocrates in the "Epidemics", ' the disease, the patient, the physician. The physician is the servant of the art. The patient must co-operate with the physician in combating the disease.' Hippocrates identified the elements; he postulated a solution; the consequences of this view of the healing process form the subject of this volume.(AU)


Assuntos
História da Medicina , Doença
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