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1.
Molecules ; 26(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443423

RESUMO

Chronic liver inflammation has become a major global health concern. In the absence of clinical surrogate markers to diagnose inflammatory liver disease, the intervention with effective drugs in modern medicine tends to be late. In Sri Lanka, traditional medical practitioners prescribe herbal preparations from Osbeckia octandra for the prevention and treatment of liver disorders. To test the efficacy of such treatments, we have administered thioacetamide (TAA) to male Wistar rats to induce chronic liver damage (disease control; DC) and examined how various leaf extracts: crude leaf suspension (CLS), boiled leaf extract (BLE), sonicated leaf extract (SLE), methanol leaf extract (MLE) and hexane leaf extract (HLE) of O. octandra ameliorate TAA-induced liver disease. The CLS, BLE and SLE treatments in cirrhotic rats significantly attenuated disease-related changes, such as liver weight and hepato-enzymes. The mRNA levels of Tnf-α were significantly decreased by 3.6, 10 and 3.9 times in CLS, BLE and SLE compared to DC. The same treatments resulted in significantly lower (19.5, 4.2 and 2.4 times) α-Sma levels compared to DC. In addition, Tgf-ß1 and Vegf-R2 mRNA expressions were significantly lower with the treatments. Moreover, BLE expressed a strong anti-angiogenic effect. We conclude that CLS, BLE and SLE from O. octandra have potent hepatic anti-fibrotic effects in TAA-induced liver cirrhosis.


Assuntos
Cirrose Hepática Experimental/tratamento farmacológico , Melastomataceae/química , Neovascularização Patológica/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Citocinas/genética , Citocinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Fígado/enzimologia , Fígado/patologia , Cirrose Hepática Experimental/sangue , Neovascularização Patológica/sangue , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tioacetamida , Regulação para Cima/efeitos dos fármacos , Água , Perda de Peso/efeitos dos fármacos
2.
Molecules ; 25(8)2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32326068

RESUMO

Traditional folk medicine in Sri Lanka is mostly based on plants and plant-derived products, however, many of these medicinal plant species are scientifically unexplored. Here, we evaluated the anti-inflammatory and antimicrobial potency of 28 different extracts prepared from seven popular medicinal plant species employed in Sri Lanka. The extracts were subjected to cell-based and cell-free assays of 5-lipoxygenase (5-LO), microsomal prostaglandin E2 synthase (mPGES)-1, and nitric oxide (NO) scavenging activity. Moreover, antibacterial and disinfectant activities were assessed. Characterization of secondary metabolites was achieved by gas chromatography coupled to mass spectrometric (GC-MS) analysis. n-Hexane- and dichloromethane-based extracts of Garcinia cambogia efficiently suppressed 5-LO activity in human neutrophils (IC50 = 0.92 and 1.39 µg/mL), and potently inhibited isolated human 5-LO (IC50 = 0.15 and 0.16 µg/mL) and mPGES-1 (IC50 = 0.29 and 0.49 µg/mL). Lipophilic extracts of Pothos scandens displayed potent inhibition of mPGES-1 only. A methanolic extract of Ophiorrhiza mungos caused significant NO scavenging activity. The lipophilic extracts of G. cambogia exhibited prominent antibacterial and disinfectant activities, and GC-MS analysis revealed the presence of fatty acids, sesquiterpenes and other types of secondary metabolites. Together, our results suggest the prospective utilization of G. cambogia as disinfective agent with potent anti-inflammatory properties.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Humanos , Concentração Inibidora 50 , Medicina Tradicional , Óxido Nítrico/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Prostaglandina-E Sintases/metabolismo , Sri Lanka
3.
Nat Prod Bioprospect ; 9(6): 411-417, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31729648

RESUMO

An endophytic fungus Pestalotiopsis microspora isolated from the fruits of Manilkara zapota was cultured in potato dextrose broth media. Chromatographic separation of the EtOAc extract of the broth and mycelium led to the isolation of a new azaphilonoid named pitholide E (1), in addition to previously identified pitholide B (2), pitholide D (3), pestalotin (LL-P880α) (4), PC-2 (5), LL-P880ß (6), tyrosol (7) and 4-oxo-4H-pyran-3-acetic acid (8). An endophytic fungus P. microspora from M. zapota and the isolation of compounds 1-5, 7 and 8 from P. microspora are reported here for the first time.

4.
Food Sci Nutr ; 7(2): 425-432, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30847119

RESUMO

This study investigated the effect of boiling on the inhibitory action of spices on digestive enzymes. Unboiled extracts of Trigonella foenum-graecum (seed) (25.42%), Myristica fragrans (seed) (22.70%), and Cuminum cyminum (seed) (19.17%) showed significantly (p < 0.05) a higher lipase inhibitory activity than their respective boiled extracts (20.23%, 15.74%, and 12.57%). Unboiled extracts of Cinnamomum zeylanicum (stem bark) (-16.98%) and Foeniculum officinale (seed) (-16.05%) showed an activation of lipase enzyme, and boiling significantly (p < 0.05) changed the activity into lipase inhibition as 8.47% and 9.54%, respectively. Unboiled extracts of Coriandrm sativum (seed), C. cyminum, and Elettaria cardamomum (seed) showed an activation of amylase enzyme, and boiling these extracts significantly reduced the enzyme activation. The other unboiled extracts showed a higher amylase inhibition than the boiled extracts, whereas the boiled extracts of C.longa (rhizome) and Syzygium aromaticum (flower) exhibited significantly (p < 0.05) lower values. Unboiled extracts of C. zeylanicum, M. fragrans, and S. aromaticum showed an insignificantly higher glucosidase inhibitory activity than the boiled extracts. Inhibition of digestive enzymes by nutritional intervention is one avenue to be considered in treating diet-induced obesity and in the management of postprandial hyperglycemia. Spices, used as food additives, could be a potential source of digestive enzyme inhibitors. The current study revealed that unboiled extracts of T. foenum-graecum (seed), C. cyminum (seed), and M. fragrans (seed) are more effective than the boiled extracts as an antiobesity therapy. Moreover, it endorses the use of infusion of T. foenum-graecum seeds as an antiobesity therapy.

6.
J Ethnopharmacol ; 224: 474-481, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29727733

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leucas zeylanica (L.) W.T. Aiton is a popular, multi-purpose medicinal plant in Sri Lanka but the pharmacological potential and the chemical profile have not been systematically investigated to understand and rationalize the reported ethnobotanical significance. AIM OF THE STUDY: The present study was undertaken to scientifically validate the traditional usage of this plant for the treatment of inflammatory conditions, gout and microbial infections. Inhibition of 5-lipoxygenase (5-LO), microsomal prostaglandin E2 synthase (mPGES)-1 and xanthine oxidase (XO) by different extracts of L. zeylanica was investigated to determine the anti-inflammatory and anti-gout activity, respectively. The antibacterial and antifungal activities were also studied and the relevant constituents in the bioactive extracts were tentatively identified. MATERIALS AND METHODS: Cell-free and/or cell-based assays were employed in order to investigate the effects of the extracts against the activity of human 5-LO, mPGES-1 and XO as well as to assess antioxidant properties. The antibacterial activity of the extracts was determined by the broth micro-dilution method against Gram positive and Gram negative bacteria including methicillin-resistant Staphylococcus aureus while the agar dilution method was employed to determine the anti-Candida activity. Gas chromatography coupled to mass spectrometric (GC-MS) analysis enabled the characterization of secondary metabolites in the extracts. RESULTS: The dichloromethane extract of L. zeylanica efficiently inhibited 5-LO activity in stimulated human neutrophils (IC50 = 5.5 µg/mL) and isolated human 5-LO and mPGES-1 (IC50 = 2.2 and 0.4 µg/mL). Potent inhibition of XO was observed by the same extract (IC50 = 47.5 µg/mL), which is the first report of XO-inhibitory activity of a Sri Lankan medicinal plant. Interestingly, significant radical scavenging activity was not observed by this extract. Only the n-hexane extract exhibited antibacterial activity against Staphylococcus aureus and Staphylococcus saprophyticus with a MIC of 250 µg/mL while the anti-Candida activity was moderate. GC-MS analysis revealed the presence of phytosterols, fatty acids, sesquiterpenes, diterpenes and several other types of secondary metabolites. CONCLUSIONS: Potent inhibition of 5-LO, mPGES-1 and XO rationalizes the ethnopharmacological use of L. zeylanica as anti-inflammatory and anti-gout remedy. Interestingly, the antimicrobial activities were not prominent, despite its wide utility as an antimicrobial medication.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Supressores da Gota/farmacologia , Lamiaceae , Inibidores de Lipoxigenase/farmacologia , Extratos Vegetais/farmacologia , Células A549 , Anti-Infecciosos/química , Anti-Inflamatórios/química , Antioxidantes/química , Araquidonato 5-Lipoxigenase/química , Araquidonato 5-Lipoxigenase/metabolismo , Compostos de Bifenilo/química , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Supressores da Gota/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Inibidores de Lipoxigenase/química , Microssomos/efeitos dos fármacos , Microssomos/enzimologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/enzimologia , Fitoterapia , Picratos/química , Extratos Vegetais/química , Plantas Medicinais , Prostaglandina-E Sintases/antagonistas & inibidores , Prostaglandina-E Sintases/metabolismo , Sri Lanka , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/química , Xantina Oxidase/metabolismo
7.
J Chem Ecol ; 44(1): 95-101, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29292470

RESUMO

The tea shot-hole borer beetle (TSHB, Euwallacea fornicatus) causes serious damage in plantations of tea, Camellia sinensis var. assamica, in Sri Lanka and South India. TSHB is found in symbiotic association with the ambrosia fungus, Monacrosporium ambrosium (syn. Fusarium ambrosium), in galleries located within stems of tea bushes. M. ambrosium is known to be the sole food source of TSHB. Six naphthoquinones produced during spore germination in a laboratory culture broth of M. ambrosium were isolated and identified as dihydroanhydrojavanicin, anhydrojavanicin, javanicin, 5,8-dihydroxy-2-methyl-3-(2-oxopropyl)naphthalene-1,4-dione, anhydrofusarubin and solaniol. Chloroform extracts of tea stems with red-colored galleries occupied by TSHB contained UV active compounds similar to the above naphthoquinones. Laboratory assays demonstrated that the combined ethyl acetate extracts of the fungal culture broth and mycelium inhibited the growth of endophytic fungi Pestalotiopsis camelliae and Phoma multirostrata, which were also isolated from tea stems. Thus, pigmented naphthoquinones secreted by M. ambrosium during spore germination may prevent other fungi from invading TSHB galleries in tea stems. The antifungal nature of the naphthoquinone extract suggests that it protects the habitat of TSHB. We propose that the TSHB fungal ectosymbiont M. ambrosium provides not only the food and sterol skeleton necessary for the development of the beetle during its larval stages, but also serves as a producer of fungal inhibitors that help to preserve the purity of the fungal garden of TSHB.


Assuntos
Ascomicetos/química , Camellia sinensis/microbiologia , Besouros/microbiologia , Naftoquinonas/análise , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/fisiologia , Camellia sinensis/crescimento & desenvolvimento , Clorofórmio/química , Ecossistema , Espectroscopia de Ressonância Magnética , Naftoquinonas/isolamento & purificação , Naftoquinonas/farmacologia , Caules de Planta/química , Caules de Planta/microbiologia , Esporos Fúngicos/química , Esporos Fúngicos/crescimento & desenvolvimento , Simbiose
8.
Nat Prod Res ; 32(20): 2483-2486, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29260908

RESUMO

Phialemonium curvatum, an endophytic fungus isolated from the leaves of Passiflora edulis was cultured in potato dextrose broth (PDB) media and chromatographic separation of the EtOAc extract of the broth and mycelium led to the isolation of 4-hydroxybenzoic acid (1), 3-indole acetic acid (2), solaniol (3), uracil (4), uridine (5) and glycerol (6). Compound 2 showed a weak antifungal activity against Cladosporium cladosporioides. This is the first report of the isolation of the endophytic fungus P. curvatum from P. edulis and complete 13CNMR assignments of 3.


Assuntos
Passiflora/microbiologia , Xylariales/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Cladosporium/efeitos dos fármacos , Endófitos/química , Ácidos Indolacéticos/isolamento & purificação , Ácidos Indolacéticos/farmacologia , Fungos Mitospóricos/química , Estrutura Molecular , Folhas de Planta/microbiologia , Metabolismo Secundário
9.
Nat Prod Commun ; 12(4): 489-490, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30520578

RESUMO

An endophytic fungus Talaronyces pinpurogenus was isolated from the seeds of the popular edible fruit Pouteria campechiana. The fungus was fermented in potato dextrose agar and the fungal media were extracted with EtOAc. Chromatographic separation of the EtOAc extracts over silica gel, Sephadex LH-20 and preparative thin layer chromatography furnished a furanone analogue of talaroconvolutin A, named talarofuranone (1), along with talaroconvolutin A (2), 4-hydroxyactophenone, tyrosol and ergosterol. The structure of 1 was determined by comparing the NMR data with that of 2 and by HRFABMS.


Assuntos
Endófitos/química , Endófitos/isolamento & purificação , Pouteria/microbiologia , Pirrolidinonas/química , Talaromyces/química , Talaromyces/isolamento & purificação , Cromatografia em Camada Delgada , Endófitos/classificação , Endófitos/genética , Frutas/microbiologia , Espectroscopia de Ressonância Magnética , Pirrolidinonas/isolamento & purificação , Sementes/microbiologia , Talaromyces/classificação , Talaromyces/genética
10.
Pharm Biol ; 55(1): 206-211, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27927056

RESUMO

CONTEXT: Pancreatic α-amylase and α-glucosidase inhibitors serve as important strategies in the management of blood glucose. Even though Syzygium cumini (L.) Skeels (Myrtaceae) (SC) is used extensively to treat diabetes; scientific evidence on antidiabetic effects of SC leaves is scarce. OBJECTIVE: SC leaf extract was investigated for α-amylase inhibitory effect and continued with isolation and identification of α-amylase inhibitors. MATERIALS AND METHODS: Bioassay-guided fractionation was conducted using in vitro α-amylase inhibitory assay (with 20-1000 µg/mL test material) to isolate the inhibitory compounds from ethyl acetate extract of SC leaves. Structures of the isolated inhibitory compounds were elucidated using 1H NMR and 13C NMR spectroscopic analysis and direct TLC and HPLC comparison with authentic samples. Study period was from October 2013 to October 2015. RESULTS: An active fraction obtained with chromatographic separation of the extract inhibited porcine pancreatic α-amylase with an IC50 of 39.9 µg/mL. Furthermore, it showed a strong inhibition on α-glucosidase with an IC50 of 28.2 µg/mL. The active fraction was determined to be a 3:1 mixture of ursolic acid and oleanolic acid. Pure ursolic acid and oleanolic acid showed IC50 values of 6.7 and 57.4 µg/mL, respectively, against α-amylase and 3.1 and 44.1 µg/mL respectively, against α-glucosidase. DISCUSSION AND CONCLUSIONS: The present study revealed strong α-amylase and α-glucosidase inhibitory effects of ursolic acid and oleanolic acid isolated from SC leaves for the first time validating the use of SC leaves in antidiabetic therapy.


Assuntos
Bioensaio , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Pâncreas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Syzygium/química , alfa-Amilases/antagonistas & inibidores , Acetatos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Hipoglicemiantes/isolamento & purificação , Estrutura Molecular , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Pâncreas/enzimologia , Extratos Vegetais/isolamento & purificação , Espectroscopia de Prótons por Ressonância Magnética , Solventes/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , alfa-Amilases/metabolismo
11.
BMC Complement Altern Med ; 16(1): 479, 2016 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-27881112

RESUMO

BACKGROUND: The constant exposure to solar ultraviolet radiation (UV) has a variety of harmful effects on human health. Although synthetic sunscreen products have been introduced as a preventive/therapeutic strategy, with the realization of their adverse side effects, the recent trend is to search for human friendly alternative formulations especially of plant origin. Therefore, the present study focuses on evaluation of photoprotective activity of aqueous extracts (1 mg/ml) of eleven medicinal plants in Sri Lanka that have been widely employed in traditional medicine as treatment options for various skin diseases and to improve the complexion. METHODS: For the determination of UV filtering potential of the extracts, UV absorption was measured and the sun protection factor (SPF) was calculated according the Mansur equation. The antioxidant activity was evaluated by DPPH and ABTS assays. RESULTS: Among the extracts, Atalantia ceylanica, Hibiscus furcatus, Leucas zeylanica, Mollugo cerviana, Olax zeylanica and Ophiorrhiza mungos have displayed SPF value ≥ 25, which are even higher than two commercial photoprotective creams used as reference compounds. L. zeylanica and O. mungos have displayed a high UV absorbance in 260-350 nm range indicating their potential of being broad spectrum sunscreens. In addition, the extract of O. mungos was found to be photostable, without any significant reduction in the SPF after exposure to direct solar radiation for 21 days. DPPH assay and the ABTS assay revealed that the extracts possess high antioxidant activity. CONCLUSION: The results of the present study suggest that the presence of secondary metabolites with antioxidant property could be responsible for the high UV absorbance. Our findings would offer an exciting avenue for further research towards the development of herbal cosmetics.


Assuntos
Preparações de Plantas/uso terapêutico , Plantas Medicinais , Protetores Solares/uso terapêutico , Antioxidantes/uso terapêutico , Humanos , Fitoterapia , Dermatopatias/tratamento farmacológico , Sri Lanka , Raios Ultravioleta
12.
Nat Prod Commun ; 10(10): 1659-60, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26669097

RESUMO

Nigrospora oryzae was isolated as an endophytic fungus from the leaves of Coccinia grandis, a popular medicinal plant used to control diabetes. Fermentation of the fungus in potato dextrose broth and chromatographic purification of the ethyl acetate extracts of the broth and mycelium yielded two phenazine secondary metabolites, which were identified as phenazine-1-carboxylic acid (1) and phenazine-1-carboxamide (2) by comparing their spectral data with those reported in the literature. Compound 2, isolated in high yield (1 g/4 L medium), showed strong antifungal activity against the plant pathogen Cladosporium cladosporioides. This is the first report of the isolation of N. oryzae as an endophytic fungus of C. grandis. These phenazines have never been isolated from any fungal source. Antifungal activity of 2 against C. cladosporioides is reported for the first time.


Assuntos
Ascomicetos/química , Cucurbitaceae/microbiologia , Endófitos/metabolismo , Fenazinas/metabolismo , Plantas Medicinais/microbiologia , Policetídeos/química , Endófitos/química , Fenazinas/química
13.
Nat Prod Commun ; 10(10): 1663-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26669099

RESUMO

Aspergillus awamori was isolated from a diseased banana fruit, Musa acuminata cv. Ambul. The fungus was fermented in potato dextrose broth and on potato dextrose agar media and the fungal media were extracted with EtOAc. Chromatographic separation of the EtOAc extracts furnished 4-methoxybenzyl 7-phenylacetamido-3-vinyl-3-cephem-4-carboxylate (1), along with three naphtho-γ-pyrones, flavasperone (2), foncesinone A (3) and aurasperone A (4), and three alkaloids, aspernigrin A (5), pestalamide C (6) and nigragillin (7). Compound 1, a known key intermediate in the chemical synthesis of cepham antibiotics, was isolated from a natural source for the first time. Compound 1 is the first 3-vinyl cephem derivative of microbial origin.


Assuntos
Antibacterianos/síntese química , Aspergillus/química , Frutas/microbiologia , Musa/microbiologia , Fermentação , Estrutura Molecular
14.
J Food Sci Technol ; 52(12): 8383-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604419

RESUMO

Flacourtia inermis Roxb. (Flacourtiaceae), is a moderate sized tree cultivated in Sri Lanka for its fruits known as Lovi. The current study was undertaken to study the biological activity of extracts of the fruits in an attempt to increase the value of the under exploited fruit crops. Fruits of F. inermis were found to be rich in phenolics and anthocyanins. Polyphenol content of the fruits was determined to be 1.28 g gallic acid equivalents per 100 g of fresh fruit and anthocyanin content was estimated as 108 mg cyanidin-3-glucoside equivalents per 100 g of fresh fruits. The EtOAc extract showed moderate antioxidant activity in the DPPH radical scavenging assay with IC50 value of 66.2 ppm. The EtOAc and MeOH extracts of the fruits also exhibited inhibitory activities toward α-glucosidase, α-amylase and lipase enzymes with IC50values ranging from 549 to 710 ppm, 1021 to 1949 ppm and 1290 to 2096 ppm, respectively. The active principle for the enzyme inhibition was isolated through activity-guided fractionation and was characterized as (S)-malic acid. The results of this study indicate that F. inermis fruits have the potential to be used in health foods and in nutritional supplements.

15.
Nat Prod Res ; 29(14): 1384-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25809933

RESUMO

Endophytic fungi are considered as a good source to produce important secondary metabolites with interesting bioactivities. In a continuation of our studies towards the search for environmentally friendly bioactive compounds from Sri Lankan flora, we investigated the secondary metabolites produced by the endophytic fungi Aspergillus sp. isolated from the seeds of the popular edible fruit Limonia acidissima L. of the family Rutaceae. The pure culture of the Aspergillus sp. was grown on potato dextrose broth media. After 4 weeks fermentation, fungal media were extracted with organic solvents. Chromatographic separation of the fungal extracts over silica gel, Sephadex LH-20 and RP-HPLC furnished flavasperone (1), rubrofusarin B (2), aurasperone A (3), fonsecinone D (4) and aurasperone B (5). Compounds 1-4 showed moderate activities in brine shrimp toxicity assay. This is the first report of the (13)C NMR data of compounds 4 and 5.


Assuntos
Aspergillus/química , Rutaceae/microbiologia , Sementes/química , Animais , Artemia/efeitos dos fármacos , Cromonas/química , Cromonas/isolamento & purificação , Endófitos/química , Estrutura Molecular , Pironas/química , Pironas/isolamento & purificação , Metabolismo Secundário , Sri Lanka , Testes de Toxicidade
16.
Mycology ; 6(3-4): 158-160, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30151324

RESUMO

A fungal endophyte isolated from the leaves of the allelopathic plant Amaranthus viridis of the family Amaranthaceae was identified as Chaetomium globosum through molecular means using internal transcribed spacer (ITS) region of rDNA gene. This is the first report of the isolation of C. globosum from Amaranthaceae. Chromatographic separation of the EtOAc extract of the fungal fermentation in potato dextrose broth yielded two known chlorine-containing azaphilone derivatives, chaetomugilin D (1) and chaetomugilin J (2). Compounds 1 and 2 were found to show phytotoxic activity in the lettuce (Lactuca sativa) seed germination bioassay. The IC50 values of 1 and 2 for root growth inhibition were 24.2 and 22.6 ppm, respectively, while IC50 values for shoot growth inhibition were 27.8 and 21.9 ppm, respectively. Phytotoxic activities of the chaetomugilin group of compounds have been reported for the first time, although their antifungal, antimicrobial and cytotoxic activities are known.

17.
J Mass Spectrom ; 47(4): 502-15, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22689627

RESUMO

The proanthocyanidins of the leaves of 16 taxa of the Rhododendron genus (Ericaceae) [Rhododendron 'Catawbiense Grandiflorum', Rhododendron 'Cunningham's White', Rhododendron smirnowii Trautv., Rhododendron calophytum Franch., Rhododendron dichroanthum ssp. scyphocalyx (Balf. f. & Forrest ) Cowan, Rhododendron micranthum Turcz., Rhododendron praevernum Hutch., Rhododendron ungernii Trautv., Rhododendron kaempferi Planch., Rhododendron degronianum ssp. heptamerum var. hondoense (Nakai ) H. Hara, Rhododendron fortunei Lindl., Rhododendron ponticum L., Rhododendron galactinum Balf. f. ex Tagg., Rhododendron oreotrephes W. W. Sm., Rhododendron brachycarpum ssp. brachycarpum D. Don ex G. Don, and Rhododendron insigne Hemsl. & E. H. Wilson ] were investigated qualitatively by liquid chromatography-mass spectrometry in series. Twenty-nine dimeric proanthocyanidins based on (epi)catechin and (epi)gallocatechin were detected and characterized on the basis of their unique fragmentation pattern in the negative ion mode tandem mass spectrometry spectra. All of them were extracted for the first time from these sources, and ten of them were not reported previously in nature. The position of the galloyl residue was assigned on the basis of the retro-Diels-Alder fragmentation and the dehydrated retro-Diels-Alder fragmentation; it resulted from the loss of gallic acid as a neutral loss in the negative ion mode. Furthermore, four caffeoylquinic acids, six p-coumaroylquinic acids, epigallocatechin, gallocatechin, catechin, epicatechin, epigallocatechin gallate, catechin gallate, epicatechin gallate, gallocatechin gallate, two quercetin-O-hexosides, quercetin-O-galloyl-hexoside, quercetin-O-pentoside, quercetin-O-rhamnoside, quercetin-O-pentoside-O-hexoside, quercetin-O-rhamnoside-O-hexoside, quercetin-O-feruloyl-hexoside, quercetin-O-(p-hydroxy)benzoyl-hexoside, taxifolin-O-pentoside, myricetin-O-rhamnoside, two myricetin-O-pentosides, three myricetin-O-hexosides, and two myricetin-O-galloyl-hexosides were detected and shown to possess characteristic tandem mass spectrometry spectra and were tentatively assigned on the basis of their retention time.


Assuntos
Catequina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Proantocianidinas/química , Rhododendron/química , Espectrometria de Massas em Tandem/métodos , Catequina/análise , Catequina/química , Glicosídeos/análise , Glicosídeos/química , Extratos Vegetais/química , Folhas de Planta/química , Proantocianidinas/análise , Ácido Quínico/análise , Ácido Quínico/química
18.
Nat Prod Res ; 26(8): 717-21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21923561

RESUMO

Chemical investigation of the leaves of Elaeocarpus serratus yielded myricitrin (1), mearnsetin 3-O-ß-D-glucopyranoside (2), mearnsitrin (3), tamarixetin 3-O-α-L-rhamnopyranoside (4) and the fruits of Filicium decipiens yielded three flavonol glycosides, kaempferol 3-O-rutinoside (5), kaempferol 3-O-robinobioside (6) and trifolin (7). Compound 1 showed strong antioxidant activity against DPPH.


Assuntos
Antioxidantes/isolamento & purificação , Elaeocarpaceae/química , Flavonóis/isolamento & purificação , Sapindaceae/química , Frutas/química , Glicosídeos/isolamento & purificação , Estrutura Molecular , Folhas de Planta/química , Sri Lanka , Árvores/química
19.
Nat Prod Res ; 26(3): 278-81, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21985676

RESUMO

A chemical investigation of the fruit juice of Flacourtia inermis furnished five caffeoylquinic acid derivatives: methyl chlorogenate (1), methyl 5-O-caffeoylquinate (2), methyl 4-O-caffeoylquinate (3), n-butyl chlorogenate (4), n-butyl 5-O-caffeoylquinate (5) and a rare phenolic glucoside (rel)-6α-benzoyloxy-1α,2α-dihydroxy-5-oxocyclohex-3-enecarboxylic acid 2-(6-O-benzoyl-ß-D-glucopyranosyloxy)-5-hydroxybenzyl ester (6), together with quinic acid (7) and malic acid (8). Compounds 1, 2, 4 and 5 showed strong radical scavenging properties towards the 2,2'-diphenyl-1-picrylhydrazyl radical.


Assuntos
Fenóis/análise , Salicaceae/química
20.
J Med Chem ; 51(19): 6055-66, 2008 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-18771254

RESUMO

A study that was designed to identify plausible replacements for highly basic guanidine moiety contained in potent MC4R agonists, as exemplified by 1, led to the discovery of initial nonguanidine lead 5. Propyl analog 23 was subsequently found to be equipotent to 5, whereas analogs bearing smaller and branched alkyl groups at the 3 position of the oxopiperazine template demonstrated reduced binding affinity and agonist potency for MC4R. Acylation of the NH2 group of the 4F-D-Phe residue of 3-propyl analog 23 significantly increased the binding affinity and the functional activity for MC4R. Analogs with neutral and weakly basic capping groups of the D-Phe residue exhibited excellent MC4R selectivity against MC1R whereas those with an amino acid had moderate MC4R/MC1R selectivity. We have also demonstrated that compound 35 showed promising oral bioavailability and a moderate oral half life and induced significant weight loss in a 28-day rat obesity model.


Assuntos
Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Obesidade/tratamento farmacológico , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Receptor Tipo 4 de Melanocortina/agonistas , Administração Oral , Animais , Fármacos Antiobesidade/química , Disponibilidade Biológica , Dieta , Modelos Animais de Doenças , Cães , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Conformação Molecular , Piperazinas/química , Ratos , Estereoisomerismo
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