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1.
Fitoterapia ; 176: 106041, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823598

RESUMO

Stemona collinsiae Craib., Stemonaceae, has been traditionally used as medicinal plants for insecticides, treatment of parasitic worms and various diseases in Southeast Asian countries. Its ethanolic root extract has been postulated for anthelminthic activities which has a potential for development for human gnathostomiasis drug. To investigate the pharmacokinetic profile, liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method for the quantification of didehydrostemofoline in rats' plasma was developed and validated. The chromatographic separation was performed on a C18 column using 1 mM ammonium acetate in water and methanol (50:50, v/v). Tetrahydropalmatine was used as an internal standard. The multiple reaction monitoring mode was used for quantitative analysis. The validated method showed good sensitivity, linearity, precision, and accuracy. The results of stability showed that didehydrostemofoline was stable in the extracted samples in auto-sampler for 24 h and in the plasma samples under room temperature for 24 h, -20 °C for 1 month, and after three freeze-thaw processes. The developed method was applied to the pharmacokinetic study of didehydrostemofoline after oral administration of S. collinsiae root extract. Didehydrostemofoline was rapidly absorbed from the gastrointestinal tract. The time to peak drug concentration was 1.75 ± 0.62 h with maximum drug concentration of 1152.58 ± 271.18 ng/mL. Didehydrostemofoline was rapidly eliminated from the body with terminal half-life of 1.86 ± 0.50 h. Calculated drug clearance of didehydrostemofoline was 96.82 ± 23.51 L/h and volume of distribution was 260.40 ± 96.81 L. The present study provided useful data for understanding drug disposition in the body with dynamic time-course which could be beneficial for further clinical trials.


Assuntos
Extratos Vegetais , Raízes de Plantas , Ratos Sprague-Dawley , Stemonaceae , Espectrometria de Massas em Tandem , Animais , Stemonaceae/química , Espectrometria de Massas em Tandem/métodos , Raízes de Plantas/química , Ratos , Extratos Vegetais/farmacocinética , Extratos Vegetais/química , Administração Oral , Masculino , Cromatografia Líquida/métodos , Estrutura Molecular , Espectrometria de Massa com Cromatografia Líquida , Compostos Heterocíclicos de 4 ou mais Anéis
2.
Phytochemistry ; 222: 114075, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38570006

RESUMO

Six undescribed bisindole alkaloids, namely taberdisines A-F (1-6), were isolated from the leaves of Tabernaemontana divaricata 'Dwaft'. Among them, alkaloids 1 and 2 were the first examples of strychnos-iboga type alkaloid with both C-C linkage patterns. Alkaloid 3, a new type of aspidosperma-iboga with a furan-ring, as well as other three undescribed ones was disclosed. Their structures were elucidated by comprehensive spectroscopic analyses. Alkaloids 1 and 5 showed insecticide activity on Sf9 cell and eggs of Spodoptera frugiperda in vivo, which might explain the potential of the plants for insect resistance.


Assuntos
Alcaloides Indólicos , Inseticidas , Folhas de Planta , Spodoptera , Tabernaemontana , Tabernaemontana/química , Folhas de Planta/química , Inseticidas/química , Inseticidas/farmacologia , Inseticidas/isolamento & purificação , Animais , Spodoptera/efeitos dos fármacos , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/farmacologia , Estrutura Molecular , Células Sf9
3.
Phytochemistry ; 222: 114077, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615925

RESUMO

Two undescribed bisindole alkaloids, gelseginedine A (1) and its rearranged gelseginedine B (2), and seven unreported gelselegine-type oxindole alkaloids (3-9) were isolated from the stems and leaves of Gelsemium elegans, together with five known alkaloids (10-14). Compounds 1 and 2 represented the first examples of gelselegine-gelsedine type alkaloids which bridged two units by a double bond. Their structures with absolute configurations were elucidated by means of HRESIMS, NMR and calculational chemistry. The performed bioassay revealed that 14 could promote the proliferation of human oral mucosa fibroblast cells.


Assuntos
Fibroblastos , Gelsemium , Indóis , Extratos Vegetais , Indóis/isolamento & purificação , Indóis/farmacologia , Gelsemium/química , Fibroblastos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Folhas de Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Estrutura Molecular , Caules de Planta/química , Humanos
4.
PeerJ ; 12: e16774, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38282858

RESUMO

Trema orientalis is a pioneer species in the cannabis family (Cannabaceae) that is widely distributed in Thai community forests and forest edges. The mature leaves are predominantly used as an anti-parasite treatment and feed for local freshwater fish, inspiring investigation of their phytochemical composition and bioactivity. The purpose of this work was to investigate the bioactive compounds in T. orientalis leaf extract and their cytotoxicity in the BF-2 fish cell line (ATCC CCL-91). Flash column chromatography was used to produce 25 mL fractions with a mixture solvent system comprised of hexane, diethyl ether, methanol, and acetone. All fractions were profiled with HPLC-DAD (mobile phase methanol:aqueous buffer, 60:40 v/v) and UV detection (wavelengths 256 and 365 nm). After drying, a yellowish powder was isolated from lipophilic leaf extract with a yield of 280 µg/g dry weight. Structure elucidation by nuclear magnetic resonance (NMR) indicated it to consist of pure ß-sitosterol. The lipophilic extract and pure compound were evaluated for cytotoxicity using BF-2 cells. MTT assays showed both leaf extract and pure compound at 1 µg/mL to increase cell viability after 24 h treatment. The respective half maximal inhibitory concentration (IC50) values of leaf extract and ß-sitosterol were 7,027.13 and 86.42 µg/ml, indicating a lack of toxicity in the BF-2 cell line. Hence, T. orientalis can serve as a source of non-toxic natural lipophilic compounds that can be useful as bioactive ingredients in supplement feed development.


Assuntos
Cannabaceae , Sitosteroides , Trema , Animais , Trema/química , Extratos Vegetais/farmacologia , Metanol , Proliferação de Células
5.
Bioorg Chem ; 130: 106239, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36371820

RESUMO

Fifteen undescribed Stemona alkaloids, named as stemarines A-O (1-15), along with 25 known alkaloids (16-40), were isolated and identified from the roots of Stemona mairei (H.Lév.)K.Krause (Stemonaceae). Their structures were elucidated through the analysis of the NMR spectra, mass data, and computational chemistry. All the hitherto undescribed compounds possess a pyrrolo[1,2-α]azepine core structure but differ in important structural features, which reflects their nematocidal activities. Alkaloids 3-6 featured a carboxylic side chain and exhibited significant nematocidal activity against the nematode Caenorhabditis elegans. Transections of fresh roots combined with application of the Dragendorff' reagent on the tissue indicated accumulation of alkaloids mainly in the epidermis and the pith. These results suggest the key pharmacophore of these alkaloids lies in the aliphatic side chain of these compounds and its spatial distribution in the roots indicate protective effects against underground herbivores.


Assuntos
Alcaloides , Stemonaceae , Stemonaceae/química , Antinematódeos , Extratos Vegetais/química , Alcaloides/farmacologia , Alcaloides/química , Raízes de Plantas/química , Estrutura Molecular
6.
Bioorg Chem ; 116: 105314, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34500306

RESUMO

Continued interest in bioactive monoterpenoid indole alkaloids and the purpose to explore the artificial cultivation influence on the chemical composition in the same plant species, 8 undescribed Aspidosperma-type alkaloids including two unprecedented trimers, taberdivarines A-B (1-2), and six new dimers, taberdivarines CH (3-8), together with 9 known bisindoles were isolated from the leaves of Tabernaemontana divaricata 'Dwaft'. Notably, taberdivarines A and B were the first cases of Aspidosperma-Aspidosperma-Aspidosperma-type alkaloids with furan ring linkage patterns of the natural products. Their structures were elucidated by comprehensive spectroscopic analyse. Compounds 1-8 were screened for the cytotoxicity against three human cancer cell lines, SMMC-7721, HT-29 and A549. Among them, Compound 6 exhibited significant activity against three cell lines with IC50 values of 0.30, 0.75 and 3.41 µM, respectively (IC50 = 3.02, 0.14 and 2.23 µM for the positive control, vinorelbine). Compound 1, 3, 4, 6, 7 and 8 also expressed varying degrees of activity. The structure-activity relationships (SARs) of these alkaloids were discussed.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Folhas de Planta/química , Tabernaemontana/química , Alcaloides/química , Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
7.
Chin Herb Med ; 12(2): 200-203, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36119802

RESUMO

Objective: The study was conducted to develop and validate a high performance thin-layer chromatography (HPTLC)-densitometric method for the quantitative analysis of morin in Maclura cochinchinensis heartwood collected from different locations in Thailand. Methods: HPTLC analysis was performed on an aluminium sheet of silica gel 60 F254 using toluene: ethyl acetate: formic acid (36:12:7, volume percent) as a mobile phase. The densitometric scanning was performed at the wavelength 410 nm. HPTLC method was validated according to ICH guideline. Results: The proposed HPTLC method showed acceptable validation parameters. The content of morin in M. cochinchinensis heartwood collected from eight different provinces in Thailand were in the ranges of 1.53%-2.73%. Conclusion: The simple and sensitive HPTLC method was successfully developed and validated for determination of morin in M. cochinchinensis heartwood. The proposed HPTLC method was found to be simple, fast and inexpensive, and can be used for the routine quality control of raw materials.

8.
Chin Herb Med ; 12(4): 452-455, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36120174

RESUMO

Objective: To isolate and identify the major bioactive components from the leaves of Lysiphyllum strychnifolium, an indigenous herb used in traditional Thai medicine for detoxification, longevity, and some other health related issues. Methods: Comparative HPLC analyses of the crude extracts from three provenances were carried out for an overview of characteristic compound profiles. Isolation of the major compounds was undertaken with chromatographic methods. Chemical structures were elucidated by NMR spectroscopic techniques and mass spectrometry. DPPH scavenging assay was carried out to determine the free radical scavenging activity of isolated compounds. Results: Yanangdaengin (3), a dihydrochalcone glucoside galloyl ester, has been isolated together with its corresponding dihydrochalcone glucoside trilobatin (2) as major compounds from the leaves of L. strychnifolium. Additionally, gallic acid (1) was co-chromatographically identified. Free radical scavenging activity of isolated compounds were determined. Compound 3 exhibited higher free radical scavenging activities in comparison to Trolox and quercetin. Conclusion: The isolated compounds could be used as chemical markers for quality assessment. The present work could promote the quality control and herbal medicinal product development of this plant.

9.
Vet Dermatol ; 30(6): 487-e145, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31441182

RESUMO

BACKGROUND: Staphylococcus pseudintermedius, commonly involved in canine pyoderma, can be classified as meticillin-susceptible S. pseudintermedius (MSSP) or meticillin-resistant S. pseudintermedius (MRSP). MRSP infections may be difficult to treat due to broad ß-lactam resistance of MRSP and typically additional multidrug-resistance. Topical antibacterial treatment is the preferred treatment modality for surface and superficial skin infections. HYPOTHESIS/OBJECTIVES: Mangosteen crude extract containing the antibacterial compound α-mangostin will have in vitro activity against MSSP and MRSP isolated from canine pyoderma. BACTERIAL ISOLATES: Twenty-three samples, MSSP (n = 12) and MRSP (n = 11), isolated from canine pyoderma. METHODS AND MATERIALS: Minimum inhibitory concentrations (MICs) were determined for mangosteen crude extract by broth microdilution. High-performance liquid chromatography (HPLC) analysis was used to determine the amount of α-mangostin in mangosteen crude extract. A time-kill assay was performed at 30 min and 2 h after exposure to a high concentration of crude extract (100× MIC). Antibacterial activity for α-mangostin was calculated according to HPLC results. RESULTS: The concentration of α-mangostin was 17.72 ± 1.42% w/w. The mean MIC of α-mangostin towards MSSP was 0.53 ± 0.35 µg/mL, whereas the mean value for MRSP was 0.47 ± 0.27 µg/mL. There was no difference between the mean MIC of MRSP and MSSP (P = 0.84). After a 30 min exposure to 100× MIC of the crude extract, a 95% reduction in colony forming units was found. CONCLUSIONS AND CLINICAL IMPORTANCE: The results showed that α-mangostin in mangosteen crude extract was effective in inhibiting S. pseudintermedius (both MRSP and MSSP). Clinical studies are needed to investigate this effectiveness further in vivo.


Assuntos
Antibacterianos/farmacologia , Garcinia mangostana/química , Extratos Vegetais/farmacologia , Pioderma/veterinária , Staphylococcus/efeitos dos fármacos , Xantonas/farmacologia , Animais , Cães , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Pioderma/microbiologia
10.
Phytochem Anal ; 30(6): 617-622, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31020748

RESUMO

INTRODUCTION: Quantitative nuclear magnetic resonance (qNMR) spectroscopy is an analytical method based on the principles of NMR spectroscopy. The main advantages of this method are its simplicity, time efficiency, high accuracy and reproducibility, and it is a non-destructive technique. OBJECTIVE: To evaluate and standardise the quality of Artocarpus lacucha heartwood. A method for quantifying its oxyresveratrol content using qNMR was developed. METHODOLOGY: Proton (1 H)NMR (400 MHz) spectroscopy was used to analyse the methanol-d4 solution of a given amount of crude extract of A. lacucha heartwood using ethyl p-methoxycinnamate (EPMC) as an internal standard. The qNMR methodology was validated in terms of its linearity and range, limit of quantification (LOQ), stability, precision, and accuracy for the determination of the oxyresveratrol content. RESULTS: The qNMR method was validated in terms of its linearity, range, LOQ, accuracy, precision, and stability. The quantitative determination of the oxyresveratrol content in the methanolic crude extract of A. lacucha was found to be 17% based on 1 HNMR analysis, which proved to be a reliable method as the results were comparable to those obtained by high-performance liquid chromatography (HPLC) analysis. CONCLUSIONS: This study validated qNMR spectroscopy as a reliable analytical procedure to determine oxyresveratrol in A. lacucha heartwood. Therefore, this qNMR method can serve as an alternative to the classical HPLC methods for evaluating and standardising the quality of A. lacucha heartwood.


Assuntos
Artocarpus/química , Extratos Vegetais/análise , Espectroscopia de Prótons por Ressonância Magnética/métodos , Estilbenos/análise , Madeira , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Extratos Vegetais/normas , Padrões de Referência , Reprodutibilidade dos Testes , Estilbenos/normas
11.
Rev. bras. farmacogn ; 28(2): 145-150, Mar.-Apr. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-958854

RESUMO

ABSTRACT Pluchea indica (L.) Less., Asteraceae, is a medicinal plant which contains a high amount of phenolic compounds such as caffeoylquinic acid derivatives. The leaves have been traditionally used as a nerve tonic and extensively as herbal tea. This study aimed to develop and validate an HPLC method to quantitatively analyze six caffeoylquinic acid derivatives, viz. 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 5-O caffeoylquinic acid, 3,4-O-dicaffeoylquinic acid, 3,5-O-dicaffeoylquinic acid, and 4,5-O-dicaffeoylquinic acid in P. indica leaf extract. HPLC was carried out in a Hypersil BDS C18-column eluted with 0.5% acetic acid in water and methanol using gradient elution with a flow rate of 1 ml/min and detection at 326 nm. The method validation was performed to assure its linearity, precision, accuracy and limits of detection and quantitation. Several extraction techniques including maceration, decoction, digestion, Soxhlet extraction, and ultrasound extraction, were used to extract active constituents. The ultrasound extraction with 50% ethanol yielded the highest concentration of these caffeoylquinic acid derivatives in the P. indica leaf extract. Our developed HPLC method is simple and reliable for a routine analysis of the six caffeoylquinic acids in P. indica leaves and could potentially be applied to be used in commercial herbal products.

12.
Rev. bras. farmacogn ; 27(6): 691-697, Nov.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898724

RESUMO

ABSTRACT Stephania venosa (Blume) Spreng., Menispermaceae, has been traditionally used as tonic drug and treatment of various diseases in South East Asian countries. In order to evaluate the quality and standardization of S. venosa roots, the HPLC method for quantification of the content of major components in S. venosa was developed and validated. The chromatographic separation was performed on a Hypersil BDS C18 column using gradient system of 100 mM ammonium acetate in water and methanol with flow rate 1 ml/min. Detection wavelength was set at 210 nm for tetrahydropalmatine, 280 nm for dicentrine and crebanine, and 270 nm for stephanine. The validated method showed good sensitivity, linearity, precision, and accuracy. The suitable solvent that yielded highest alkaloids contents from the matrix was optimized. S. venosa samples collected from various locations were analyzed. The present study provided comprehensive overview of major components in S. venosa. A remarkable variation in the accumulation of alkaloids in each population and the between individual in the same population could be observed. Our results showed the heterogeneity of S. venosa in Thailand which would need a further study for species delimitations.

13.
Rev. bras. farmacogn ; 27(3): 290-296, May-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898674

RESUMO

Abstract Curcuma comosa Roxb., Zingiberaceae, a phytoestrogen-producing herb with vernacularly named "Wan Chak Mod Loog" in Thailand, has been traditionally used for treatment of gynecologic diseases and sold as food supplement in the market. However, similar rhizomes of its related species may lead to the confusion in the uses of this plant. This study was aimed to investigate the phytochemical constituents of different Curcuma spp. that used as "Wan Chak Mod Loog". Characteristic major compounds were isolated and identified. Phytochemical analysis of 45 Curcuma samples representing Curcuma sp., C. latifolia, and C. comosa were analyzed and compared with their phylogenetic relationship inferred by Amplified Fragment Length Polymorphism analysis. Phytoestrogen diarylheptanoids were found in all samples of C. comosa while sesquiterpenoids including hepatoxic zederone were found in C. latifolia and Curcuma sp. samples.

14.
J Chromatogr Sci ; 55(3): 346-350, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27974355

RESUMO

The HPLC-DAD method was developed to determine morin content in Maclura cochinchinensis Corner heartwood extract. The chromatographic separation was performed using a Hypersil BDS C18 column, isocratic solvent system of 0.5% acetic acid in water:acetonitrile (80:20) with 1.0 mL/min flow rate and detected at 355 nm. The standard curve of morin was linear in the range of 7-905 µg/mL. The method was precise with intra-day relative standard deviation (RSD) of lower than 1% and 2.06% for inter-day RSD. The method accuracy represented by percent recover was 99.58%. The highly efficient HPLC system developed from this study could detect morin contents in M. cochinchinensis heartwood samples collected from various locations in Thailand in the range of 0.74-1.57% w/w. This developed method provided a useful standardization procedure of M. cochincihinesis materials for further application in pharmacy and other commercial developments.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Maclura/química , Madeira/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Tailândia
15.
Nat Prod Commun ; 11(12): 1805-1806, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30508338

RESUMO

Stephania venosa (Blume) Spreng or "Sa-Bu-Leud" is a Thai medicinal plant used for treatment of cancer and diabetes, and as a blood-tonic and aphrodisiac. This plant .ontains alkaloids as its major components and has been of interest for its acetylcholinesterase (AChE) inhibitory activity. Phytochemical screening - of S. venosa was made using HPLC analysis and showed the chemical variation between the same species from different provenances. Fractionation of .S..venosa extract yielded three alkaloids, namely, dicentrine, crebanine, and tetrahydropalmatine. AChE inhibitory potential of the isolated alkaloids was evaluated using Ellman's AChE inhibition assay. Dicentrine, crebanine, and tetrahydropalmatine inhibited-AChE activity with IC(50) values of 93.5, 86.6, and 168.6 µg/mL, respectively. The AChE inhibitory activity of the tertiary protoberberine alkaloid, tetrahydropalriiatine, was lower than that of the aporphine alkaloids, dicentrine and crebanine, whereas the quaternary protoberberine alkaloid, berberine, showed a higher AChE inhibitory effect than the others.


Assuntos
Alcaloides/farmacologia , Inibidores da Colinesterase/farmacologia , Stephania/química , Acetilcolinesterase/metabolismo , Alcaloides/isolamento & purificação , Inibidores da Colinesterase/isolamento & purificação , Raízes de Plantas/química
16.
Rev. bras. farmacogn ; 25(5): 445-450, Sept.-Oct. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-765065

RESUMO

ABSTRACTThe chemical component and biological activity of propolis depend on flora area of bee collection and bee species. In the study, the propolis from three stingless bee species, Lepidotrigona ventralis Smith, Lepidotrigona terminata Smith, and Tetragonula pagdeni Schwarz, was collected in the same region of mangosteen garden from Thailand. Total phenolic content, alpha glucosidase inhibitory effect, and free-radical scavenging activity using FRAP, ABTS, DPPH assays were determined. The most potent activity of propolis extract was investigated for bioactive compounds and their quantity. The ethanol extract of T. pagdeni propolis had the highest total phenolic content 12.83 ± 0.72 g of gallic acid equivalents in 100 g of the extract, and the strongest alpha glucosidase inhibitory effect with the IC50 of 70.79 ± 6.44 µg/ml. The free-radical scavenging activity evaluated by FRAP, ABTS, DPPH assays showed the FRAP value of 279.70 ± 20.55 µmol FeSO4 equivalent/g extract and the IC50 of 59.52 ± 10.76 and 122.71 ± 11.76 µg/ml, respectively. Gamma- and alpha-mangostin from T. pagdeni propolis extract were isolated and determined for the biological activity. Gamma-mangostin exhibited the strongest activity for both alpha glucosidase inhibitory effect and free-radical scavenging activity. Using HPLC quantitative analysis method, the content of gamma- and alpha-mangostin in the extract was found to be 0.94 ± 0.01 and 2.77 ± 0.08% (w/w), respectively. These findings suggested that T. pagdeni propolis may be used as a more suitable raw material for nutraceutical and pharmaceutical products and these mangostin derivatives as markers.

17.
Artigo em Inglês | MEDLINE | ID: mdl-26347795

RESUMO

The in vitro antioxidant and antibacterial assays against clinically isolated Streptococcus suis and Staphylococcus intermedius of the extracts prepared by decoction and ethanolic reflux of different parts of Chettaphangki (Cladogynos orientalis Zipp. ex Span), including the leaves, roots, and stems, using 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay and disc diffusion method were conducted. Quantitative analysis of total phenolic and total flavonoid contents in the extracts using spectrophotometric methods was also performed. Finally, phytochemical screening by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) was conducted. Leaf ethanolic reflux extract (100 g) contained the highest total phenolic and total flavonoid contents of 7.21 ± 0.28 µg gallic acid equivalent (GAE) and 11.51 ± 2.02 µg rutin equivalent (RE), respectively. Chettaphangki extracts promoted low antioxidant activity with EC50 values in the range of 0.27-0.48 mg/mL. Extracts and fractions from the roots and stems of this plant promoted low to intermediate antibacterial activity against S. intermedius with the inhibition zones between 7 and 14 mm. The chromatographic data suggested that the leaf extracts of C. orientalis contained rutin while the root and stem extracts contained scopoletin and chettaphanin I. Rutin promoted strong antioxidant activity while chettaphanin I showed low antibacterial activity against Staphylococcus intermedius.

18.
Exp Appl Acarol ; 62(1): 115-20, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23912630

RESUMO

Stemona plants have been traditionally used against various insects in Thailand and Southeast Asian countries. The acaricidal efficacy of 9 species of Stemona grown in Thailand was evaluated against dairy cattle tick, Rhipicephalus microplus using adult immersion test and in vivo evaluation on infested calves. From the ten Stemona root extracts used in this study, S. collinsiae of a concentration 250 mg/ml possessed the highest activity. In vivo study revealed that S. collinsiae extract could significantly reduce the attached ticks on calf skin compared to the control and promoted not significantly different efficacy from flumethrin, a common pyrethroid used in dairy farms. No side effect was found on calves during the experiment. The results confirmed traditional use of S. collinsiae as a better source of insecticide than other species and could be used as guidance for further development of S. collinsiae as a herbal acaricide.


Assuntos
Inseticidas/análise , Extratos Vegetais , Rhipicephalus , Stemonaceae/química , Animais , Raízes de Plantas/química , Testes de Toxicidade
19.
Nat Prod Commun ; 8(8): 1065-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24079167

RESUMO

A simple, selective, precise, and accurate thin-layer chromatographic (TLC) image analytical method was developed and validated for simultaneous quantification of the major components in the root extracts of Stemona tuberosa (tuberostemonine, tuberostemonine N and neotuberostemonine)), and S. phyllantha (tuberostemonine and tuberostemonine A). The analysis was performed by TLC on silica gel 60 F254 aluminum plates using a mixture of dichloromethane: ethyl acetate: methanol: ammonium hydroxide (50:45:4:1) as mobile phase. Post-derivatization was employed by dipping the TLC plate into Dragendorff's reagent to visualize the spots. Image analysis of the scanned TLC plate was performed to detect the contents of tuberostemonine derivatives. The polynomial regression data for the calibration plots showed good linear relationships within the concentration range of 2-7 microg/spot. The method gave satisfactory precision, accuracy, selectivity and could simultaneously quantify tuberostemonine, tuberostemonine A, tuberostemonine N and neotuberostemonine. Dried powdered roots of S. tuberosa grown in Thailand contained 1.31 +/- 0.28, 1.63 +/- 0.18 and 1.24 +/- 0.27% tuberostemonine, tuberostemonine N, and neotuberostemonine (dry weight), respectively, while S. phyllantha roots contained 1.39 +/- 0.14% tuberostemonine and 0.39 +/- 0.08% tuberostemonine A (dry weight). The proposed method was simple, inexpensive, and more accessible to apply for many local authorities and small laboratories.


Assuntos
Alcaloides/isolamento & purificação , Stemonaceae/química , Alcaloides/química , Cromatografia em Camada Fina
20.
J Chromatogr Sci ; 51(5): 430-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23045553

RESUMO

Stemona curtisii Hook. F. (Family Stemonaceae), a prominent species distributed in the south and southwest of Thailand, has widely been used as a natural pesticide and as treatment for head lice and skin diseases. This study developed a thin-layer chromatography (TLC)-densitometric method for the simultaneous quantification of major components--stemocurtisine, stemocurtisinol and stemofoline--in the extracts from the roots of S. curtisii collected from 10 locations in Thailand. Components were found in the ranges of 0.0353-0.1949, <0.0121-0.0859 and 0.0733-0.1689 percent dry weight, respectively. The method was validated for linearity, precision, accuracy, robustness, limit of detection and limit of quantitation. The linearity was found over the range of 40-320 ng/spot with a good correlation coefficient (r > 0.9866). Intra-day and inter-day precision showed a relative standard deviation of less than 6%. The accuracy of the method was determined by a recovery study, and the average recoveries were 100.4, 100.2 and 100.3% for stemocurtisine, stemocurtisinol and stemofoline, respectively. The proposed TLC-densitometric method was found to be simple, precise, specific and inexpensive, and can be used simultaneously for the routine quality control of raw materials of S. curtisii roots, extracts and their products, and also other products containing these markers.


Assuntos
Azepinas/análise , Cromatografia em Camada Fina/métodos , Densitometria/métodos , Furanos/análise , Compostos Heterocíclicos de 4 ou mais Anéis/análise , Extratos Vegetais/análise , Stemonaceae/química
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