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1.
Nat Prod Res ; 37(3): 404-410, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34507510

RESUMO

Bixasteroid (1), one new steroid together with five known compounds (2-6), were isolated from the ethyl acetate fraction of ethanol extract of Bixa orellana fruits. All of these known compounds were isolated from the plant for the first time. Their structures were elucidated on the basis of spectroscopic analysis, and the absolute configuration of compound 1 was determined by X-ray crystallographic data analysis as well as by the quantum chemical ECD calculations. All the isolated compounds were tested for their anti-inflammatory activities. Compounds 1 and 2 showed inhibiting NO release activities in LPS-induced RAW 264.7 macrophages with the IC50 values of 4.72 ± 0.28 and 5.48 ± 1.48 µM, respectively.


Assuntos
Bixaceae , Frutas , Bixaceae/química , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Macrófagos
2.
Food Funct ; 13(6): 3590-3602, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35262135

RESUMO

Panax notoginseng has been used both as a traditional medicine and as a functional food for hundreds of years in Asia. However, the active constituents from P. notoginseng and their pharmacologic properties still need to be further explored. In this study, one new dammarane-type triterpenoid saponin (1), along with fourteen known analogs (2-15) were isolated and identified from the roots of P. notoginseng. The anti-inflammatory, anti-angiogenetic and anti-dengue virus effects of these isolated compounds were further evaluated. Compounds 1, 3, 5-7 and 10-12 exerted anti-inflammatory effects in two different zebrafish inflammatory models. Among them, 11, with the most significant activities, alleviated the inflammatory response by blocking the MyD88/NF-κB and STAT3 pathways. Moreover, compound 15 showed anti-angiogenetic activities in Tg(fli1:EGFP) and Tg(flk1:GFP) zebrafish, while 3 and 5 only inhibited angiogenesis in Tg(fli1:EGFP) zebrafish. Additionally, compounds 1, 3, 6, 8, 9 and 12 suppressed the replication of dengue virus either at the viral adsorption and entry stages or at the intracellular replication step. In conclusion, these findings enrich knowledge of the diversity of saponins in P. notoginseng and suggest that the dammarane-type triterpenoid saponins from P. notoginseng may be developed as potential functional foods to treat inflammation, angiogenesis or dengue-related diseases.


Assuntos
Panax notoginseng , Panax , Saponinas , Triterpenos , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Antivirais/metabolismo , Antivirais/farmacologia , Raízes de Plantas/metabolismo , Saponinas/metabolismo , Saponinas/farmacologia , Peixe-Zebra , Damaranos
3.
Chin J Integr Med ; 28(5): 410-418, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34581940

RESUMO

OBJECTIVE: To reveal the neuroprotective effect and the underlying mechanisms of a mixture of the main components of Panax notoginseng saponins (TSPN) on cerebral ischemia-reperfusion injury and oxygen-glucose deprivation/reoxygenation (OGD/R) of cultured cortical neurons. METHODS: The neuroprotective effect of TSPN was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, flow cytometry and live/dead cell assays. The morphology of dendrites was detected by immunofluorescence. Middle cerebral artery occlusion (MCAO) was developed in rats as a model of cerebral ischemia-reperfusion. The neuroprotective effect of TSPN was evaluated by neurological scoring, tail suspension test, 2,3,5-triphenyltetrazolium chloride (TTC) and Nissl stainings. Western blot analysis, immunohistochemistry and immunofluorescence were used to measure the changes in the Akt/mammalian target of rapamycin (mTOR) signaling pathway. RESULTS: MTT showed that TSPN (50, 25 and 12.5 µ g/mL) protected cortical neurons after OGD/R treatment (P<0.01 or P<0.05). Flow cytometry and live/dead cell assays indicated that 25 µ g/mL TSPN decreased neuronal apoptosis (P<0.05), and immunofluorescence showed that 25 µ g/mL TSPN restored the dendritic morphology of damaged neurons (P<0.05). Moreover, 12.5 µ g/mL TSPN downregulated the expression of Beclin-1, Cleaved-caspase 3 and LC3B-II/LC3B-I, and upregulated the levels of phosphorylated (p)-Akt and p-mTOR (P<0.01 or P<0.05). In the MCAO model, 50 µ g/mL TSPN improved defective neurological behavior and reduced infarct volume (P<0.05). Moreover, the expression of Beclin-1 and LC3B in cerebral ischemic penumbra was downregulated after 50 µ g/mL TSPN treatment, whereas the p-mTOR level was upregulated (P<0.05 or P<0.01). CONCLUSION: TSPN promoted neuronal survival and protected dendrite integrity after OGD/R and had a potential therapeutic effect by alleviating neurological deficits and reversing neuronal loss. TSPN promoted p-mTOR and inhibited Beclin-1 to alleviate ischemic damage, which may be the mechanism that underlies the neuroprotective activity of TSPN.


Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Panax notoginseng , Traumatismo por Reperfusão , Saponinas , Animais , Proteína Beclina-1 , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Glucose , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Mamíferos/metabolismo , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Oxigênio , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Traumatismo por Reperfusão/metabolismo , Saponinas/farmacologia , Saponinas/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo
4.
Molecules ; 26(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34641483

RESUMO

A phytochemical investigation on the roots of medicinal plant Eurycoma longifolia resulted in the isolation of 10 new highly oxygenated C20 quassinoids longifolactones G‒P (1-10), along with four known ones (11-14). Their chemical structures and absolute configurations were unambiguously elucidated on the basis of comprehensive spectroscopic analysis and X-ray crystallographic data. Notably, compound 1 is a rare pentacyclic C20 quassinoid featuring a densely functionalized 2,5-dioxatricyclo[5.2.2.04,8]undecane core. Compound 4 represents the first example of quassinoids containing a 14,15-epoxy functionality, and 7 features an unusual α-oriented hydroxyl group at C-14. All isolated compounds were evaluated for their anti-proliferation activities on human leukemia cells. Among the isolates, compounds 5, 12, 13, and 14 potently inhibited the in vitro proliferation of K562 and HL-60 cells with IC50 values ranging from 2.90 to 8.20 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Eurycoma/química , Leucemia/tratamento farmacológico , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Quassinas/farmacologia , Proliferação de Células , Células HL-60 , Humanos , Células K562 , Leucemia/patologia
6.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3123-3132, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467704

RESUMO

The chemical constituents from the leaves of Ilex guayusa were investigated. Sixteen triterpenoids were isolated from the 95% ethanol extract of dried leaves of I. guayusa by silica gel, Sephadex LH-20, and ODS column chromatographies and semi-prepa-rative HPLC. Those triterpenoids were identified by NMR, HR-MS, and literature analysis: 3ß-hydroxy-11α,12α-epoxy-24-nor-urs-4(23)-ene-28,13ß-olide(1), 3ß-hydroxy-24-nor-4(23),12-oleanadien-28-methyl ester(2), oleanolic acid(3), 3ß,28-dihydroxy-12-oleanene(4), 2α,3ß-dihydroxy-11α,12α-epoxy-24-'nor-olean-4(23)-ene-28,13ß-olide(5), ursolic acid(6), 3ß,23-dihydroxy ursolic acid(7), 3ß,28-dihydroxy-12-ursene(8), 3ß-28-nor-urs-12-ene-3,17-diol(9), 3ß-hydroxyurs-11-ene-28,13ß-olide(10), 13ß,28-epoxy-3ß-hydroxy-11-ursene(11), 3ß-hydroxy-28,28-dimethoxy-12-ursene(12), 3ß-hydroxy-24-nor-urs-4(23),12-dien-28-oic acid(13), 3ß-hydroxy-24-nor-urs-4(23),12-dien-28-methyl ester(14), 2α,3ß-dihydroxy-11α,12α-epoxy-24-nor-urs-4(23)-ene-28,13ß-olide(15) and 2α,3ß-dihydroxy-11α,12α-epoxy-24-nor-urs-4(23),20(30)-dien-28,13ß-olide(16). Compounds 1-2 were new compounds, and compounds 4-5, 7 and 9-16 were isolated from I. guayusa for the first time.


Assuntos
Medicamentos de Ervas Chinesas , Ilex guayusa , Ácido Oleanólico , Triterpenos , Estrutura Molecular , Folhas de Planta
7.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3364-3367, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34396756

RESUMO

Mansoa alliacea,commonly known as garlic vine,is native to the tropical rain forests of South America and widely cultivated in South China. As a popular folk medicine with various biological activities,however,this plant remains to be fully elucidated in terms of its phytochemical constituents. In this study,two new pyranonaphthoquinones were isolated from the 95% ethanol extract of the leaves and twigs of M. alliacea by various chromatographic approaches including silica gel,octadecyl silica( ODS),Sephadex LH-20,and preparative high-performance liquid chromatography( PHPLC). Their structures were determined to be 8,9-dimethoxy-α-lapachone( 1) and 7-hydroxy-8,9-dimethoxy-α-lapachone( 2) by comprehensive spectroscopic analyses and therefore respectively named as mansonin A( 1) and mansonin B( 2).


Assuntos
Compostos Fitoquímicos , Folhas de Planta , China , Cromatografia Líquida de Alta Pressão
8.
Zhongguo Zhong Yao Za Zhi ; 45(3): 565-571, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237514

RESUMO

To establish the UPLC fingerprint of Zhongyi Angong Niuhuang Pills, in order to evaluate its quality by chemical pattern recognition. The method was developed on a column of Poroshell 120 EC-C_(18), with methanol-0.1% formic acid solution as the mobile phase for gradient elution at a flow rate of 0.4 mL·min~(-1). The column temperature was 30 ℃,and the detective wavelength was 254 nm. The similarity of 24 batches of Angong Niuhuang Pills was compared by using Traditional Chinese Medicine Chromatographic Fingerprint Similarity Evaluation System(2004 A). Hydrophobic cluster analysis,principal components analysis and partial least squares discriminant analysis were conducted by using SIMCA 13.0 software to investigate different components among these products. The UPLC characteristic fingerprint was established in this study. And 17 common peaks were identified by standard reference and UPLC-MS. The similarity of 24 batches samples were above 0.980,which can be classified into three categories for pattern recognition. Baicalin,berberine,jatrorrhizine,wogonin and wogonoside were identified as the main markers that cause differences of various batches. The method is simple,rapid,accurate and reproducible,and can provide scientific basis for improving the quality standard of Zhongyi Angong Niuhuang Pills.


Assuntos
Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
9.
J Nat Prod ; 83(5): 1674-1683, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32310646

RESUMO

Six new quassinoids (1-6) were isolated from the roots of Eurycoma longifolia, and their structures with absolute configurations were determined unambiguously by spectroscopic analyses and single-crystal X-ray crystallographic experiments. Compounds 1 and 2 are the first members of a new class of quassinoids with an unusual C26 carbon skeleton. Compound 6 features a C20 cage-like scaffold with an unprecedented densely functionalized 2,5-dioxatricyclo[5.2.2.04,8]undecane core. The discovery of the two C26 quassinoids 1 and 2 has provided firm evidence for the better understanding the biogenetic process from C30 triterpenoid precursors to quassinoids. Compound 5 exhibited significant antifeedant activity on the diamondback moth (DBM) larvae and excellent systemic absorption and accumulated properties in Brassica chinensis.


Assuntos
Eurycoma/química , Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Quassinas/farmacologia , Triterpenos/farmacologia , Animais , Inseticidas/química , Estrutura Molecular , Extratos Vegetais/química , Quassinas/química , Quassinas/isolamento & purificação , Triterpenos/química , Triterpenos/isolamento & purificação
10.
Phytomedicine ; 61: 152843, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31039533

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) ranks third among the most common causes of cancer-related deaths worldwide. The chemotherapy for HCC is still insufficient, so far. In searching for effective anti-HCC agents from traditional Chinese medicine, we discovered that aloperine (ALO), a quinolizidine alkaloid from Sophora alopecuroides L., exerts anti-HCC activities. However, the effects of ALO on HCC have been rarely studied, and its underlying mechanisms remain unknown. PURPOSE: This study aims to evaluate the anti-HCC activities of ALO and explore its underlying mechanisms. METHODS: MTT assay and colony formation assay were used to investigate the anti-proliferative effects of ALO on human HCC Hep3B and Huh7 cells. Hoechst 33258 staining was used to observe the morphological changes of cells after ALO treatment. Flow cytometry was used to analyze apoptosis induction, the collapse of the mitochondrial membrane potential and cell cycle distribution. Western blotting was used to examine the expression levels of proteins associated with apoptosis and cell cycle arrest, and key proteins in the PI3K/Akt signaling pathway. Small interfering RNA (siRNA) transfection was used to investigate the role of Akt in ALO-induced apoptosis and cell cycle arrest. Zebrafish tumor model was used to evaluate the anti-HCC effects of ALO in vivo. RESULTS: ALO inhibited the proliferation of Hep3B and Huh7 cells. ALO induced apoptosis in HCC cells, which was accompanied by the loss of mitochondrial potential, the release of cytochrome c into cytosol, as well as the increased cleavages of caspase-9, caspase-3 and PARP. Moreover, ALO induced G2/M cell cycle arrest by downregulating the expression levels of cdc25C, cdc2 and cyclin B1. In addition, ALO inhibited activation of the PI3K/Akt signaling pathway by decreasing the expression levels of p110α, p85, Akt and p-Akt (Ser473). Further study showed that inhibition of Akt by siRNA augmented ALO-mediated apoptosis and G2/M cell cycle arrest in HCC cells. Critically, ALO inhibited the growth of Huh7 cells in vivo. CONCLUSION: We first demonstrated that ALO induced apoptosis and G2/M cell cycle arrest in HCC cells through inhibition of the PI3K/Akt signaling pathway. This study provides a rationale for ALO as a potential chemotherapeutic agent for HCC.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Piperidinas/farmacologia , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Embrião não Mamífero , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolizidinas , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra/embriologia
11.
Zhongguo Zhong Yao Za Zhi ; 43(22): 4474-4478, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30593241

RESUMO

This study aims to establish the characteristic fingerprint of the leaves of Moringa oleifera by Ultra High Performance Liquid Chromatography (UPLC) for its quality control. The method was developed on a column of Agilent Eclipse XDB-C18 with acetonitrile-0.01% TFA solution as the mobile phase by gradient elution at a flow rate of 0.5 mL·min⁻¹. The detective wavelength was 210 nm, and the column temperature was 35 °C. The 14 batches of the leaves of M. oleifera were compared for the similarity by using Traditional Chinese Medicine Chromatographic Fingerprint Similarity Evaluation System (2004A). The UPLC characteristic fingerprint was established, and twelve common peaks were identified by comparison with the references and UPLC-MS. The relative retention times were 0.08 (No. 1, adenosine), 0.14 (No. 2, L-phenylalanine), 0.22 (No. 3, 5-caffeoylquinic acid), 0.28 (No. 4, L-tryptophane), 0.42 (No. 5, 4-caffeoylquinic acid), 0.65 (No. 6, vicenin-2), 0.94 (No. 7, vitexin), 0.96 (No. 8, isovitexin), 1.00 (No. 9, isoquercitrin), 1.11 [No. 10, quercetin 3-O-ß-D-(6"-malonyl)-glucopyranoside], 1.21 (No. 11, astragalin) and 1.37 [No. 12, kaempferol 3-O-ß-D-(6"-malonyl)-glucopyranoside]. It is the first time to establish the UPLC characteristic fingerprint of the leaves of M. oleifera. The method is simple, quick and reproducible with high precision, which can provide a scientific basis for the quality control of the leaves of M. oleifera.


Assuntos
Medicamentos de Ervas Chinesas , Moringa oleifera , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Controle de Qualidade , Espectrometria de Massas em Tandem
12.
Zhongguo Zhong Yao Za Zhi ; 43(15): 3150-3156, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30200711

RESUMO

Two new flavonoid glycosides, quercetin-3-O-(4-O-crotonyl)-ß-D-glucopyranoside (1) and quercetin-3-O-[6-O-(2E)-pentenoyl]-ß-D-glucopyranoside (2), along with nine known ones, isoquercetin (3), astragalin (4), quercetin-3-O-(6-O-acetyl)-ß-D-glucopyranoside (5), kaempferol-3-O-(6-O-acetyl)-ß-D-glucopyranoside (6), quercetin-3-O-(6-O-crotonyl)-ß-D-glucopyranoside (7), kaempferol-3-O-(6-O-crotonyl)-ß-D-glucopyranoside (8), vitexin (9), isovitexin (10), and isorhamnetin-3-O-ß-D-glucopyranoside (11), were isolated from the leaves of Moringa oleifera by various chromatographic technologies. Their structures were elucidated by spectroscopic methods including UV, IR, MS, and NMR. In addition, compounds 7 and 8 were isolated from this plant for the first time.


Assuntos
Flavonoides/química , Glicosídeos/química , Moringa oleifera/química , Folhas de Planta/química , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação
13.
Zhongguo Zhong Yao Za Zhi ; 43(10): 2091-2096, 2018 May.
Artigo em Chinês | MEDLINE | ID: mdl-29933676

RESUMO

Nineteen compounds were isolated from the roots of Isatis indigotica through silica gel, Sephadex LH-20, ODS and pre-HPLC chromatography technique. Their structures were elucidated by the MS and NMR spectra as 7-hydroxydeoxyvasicinone (1), (1H-indol-3-yl) oxoacetamide (2), 1-methoxy-1H-indole-3-acetonitrile (3), arvelexin (4), 1H-indole-3-acetonitrile (5), 1H-indole-3-aldehyde (6), 1H-indole-3-acetic acid (7), 2,3-dihydro-4-hydroxy-2-oxo-indole-3-acetonitrile (8), deoxyvasicinone (9), indigotiisocoumarin A (10), cycloanthranilylproline (11), quinazoline-2,4(1H,3H)-diones (12), indirubin(13), (+)-pinoresinol (14), (+)-epipinoresinol (15), burselignan (16), (+)-isolariciresinol (17),vanillic acid (18) and 5-hydroxymaltol (19). Among them, compound 1 is a new natural product, and compound 2, 14, 15, 18 and 19 were isolated from the title plant for the first time.


Assuntos
Isatis/química , Compostos Fitoquímicos/análise , Raízes de Plantas/química
14.
Zhongguo Zhong Yao Za Zhi ; 42(13): 2503-2509, 2017 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-28840691

RESUMO

A new δ-oleanane-type triterpenoid glycoside, 3-O-(3-O-sulfo)-ß-D-glucopyranosiduronic acid 3ß-hydroxy-13(18)-oleanen- 28-oic acid 28-ß-D-glucopyranosyl ester (1), along with ten known triterpenoid glycosides, rotundinoside A (2), oblonganoside M (3), 3-O-ß-D-glucopyranosyl-(1→2)-α-L-arabinopyranosyl 3ß,19α-dihydroxy-20α- urs-12-en-28-oic acid 28-O-ß-D- glucopyranosyl ester (4), ilexsaponin B2 (5), ilexside Ⅱ (6), rotundinoside B (7), ilekudinoside B (8), ilexpublesnin E (9), ilekudinoside D (10) and ilexpernoside D (11), was isolated from the 75% ethanol extract of the roots of Ilex asprella by various chromatographic separation. Their structures were identified on the basis of MS, NMR spectroscopic analysis and chemical methods. In addition, 2-11 were isolated from I. asprella for the first time.


Assuntos
Ilex/química , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/isolamento & purificação , Raízes de Plantas/química , Glicosídeos , Estrutura Molecular
15.
J AOAC Int ; 99(6): 1619-1627, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27725073

RESUMO

GC-MS, GC-tandem MS (MS/MS), and LC-MS/MS were used to mathematically define the degradation profiles of pesticide residues in two field trials. Nineteen pesticides were studied in the first field trial and 11 in the second. The results of the field trials demonstrated that the degradation profiles of pesticide residues in green tea can be described with power functions to successfully estimate the amount of time, following pesticide application, pesticide residues appearing in tea in concentrations at and/or above the maximum residue limit (MRL) decrease to concentrations below the MRL. Stability tests on green tea samples stored at room temperature were conducted to determine whether pesticide-incurred green tea samples prepared according to the method used in the field trials would be suitable for the preparation of reference standards for laboratory-proficiency testing trials. This paper reports the results of a GC-MS, GC-MS/MS, and LC-MS/MS study, as well as the suitability of the samples prepared under these conditions for use as pesticide reference standards in tea analysis.


Assuntos
Poluentes Ambientais/análise , Poluentes Ambientais/classificação , Análise de Alimentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/classificação , Chá/química , Cromatografia Gasosa , Cromatografia Líquida , Espectrometria de Massas
16.
J AOAC Int ; 99(4): 1049-1057, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27151741

RESUMO

The degradation rate of 271 pesticide residues in aged Oolong tea at two spray concentrations, named a and b (a < b), were monitored for 120 days using GC-tandem MS (GC-MS/MS). To research the degradation trends and establish regression equations, determination days were plotted as horizontal ordinates and the residue concentrations of pesticide were plotted as vertical ordinates. Here, we consider the degradation equations of 271 pesticides over 40 and 120 days, summarize the degradation rates in six aspects (A-F), and discuss the degradation trends of the 271 pesticides in aged Oolong tea in detail. The results indicate that >70% of the determined pesticides coincide with the degradation regularity of trends A, B, and E, i.e., the concentration of pesticide will decrease within 4 months. Next, 20 representative pesticides were selected for further study at higher spray concentrations, named c and d (d > c > b > a), in aged Oolong tea over another 90 days. The determination days were plotted on the x-axis, and the differences between each determined result and first-time-determined value of target pesticides were plotted on the y-axis. The logarithmic function was obtained by fitting the 90-day determination results, allowing the degradation value of a target pesticide on a specific day to be calculated. These logarithmic functions at d concentration were applied to predict the residue concentrations of pesticides at c concentration. Results revealed that 70% of the 20 pesticides had the lower deviation ratios of predicted and measured results.


Assuntos
Poluentes Ambientais/análise , Poluentes Ambientais/química , Ensaios de Triagem em Larga Escala , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química , Chá/química , Cromatografia Gasosa , Resíduos de Praguicidas/metabolismo , Espectrometria de Massas em Tandem , Fatores de Tempo
17.
Nat Prod Commun ; 11(1): 53-5, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26996019

RESUMO

Three new aspidosperma-type alkaloids, 3-oxo-11-hydroxytabersonine (2), 1 1-hydroxytabersonine N-oxide (3) and 11-methoxytabersonine N-oxide (4), along with three known ones were isolated from the twigs and leaves of Melodinus suaveolens. The structures of the new compounds were elucidated by using spectroscopic methods, and circular dichroism experiments. The known compounds were identified by comparing their spectroscopic data with those reported in the literature.


Assuntos
Alcaloides/química , Apocynaceae/química , Estrutura Molecular , Folhas de Planta/química
18.
Zhongguo Zhong Yao Za Zhi ; 41(16): 3036-3041, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-28920345

RESUMO

Two new triterpenoid glycosides, latifolosides R and S (1 and 2), were isolated from the leaves of Ilex latifolia by various column chromatographic methods. Their structures were elucidated based on NMR spectroscopic data and chemical evidence.


Assuntos
Glicosídeos/isolamento & purificação , Ilex/química , Triterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Folhas de Planta/química
19.
J AOAC Int ; 98(5): 1428-54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26525263

RESUMO

Thirty laboratories from fom North and South America, Europe, and Asia participated in this AOAC collaborative study (15 from China; five from Germany; two each from Italy and the United States; and one each from the Republic of Korea, Canada, Spain, Japan, Belgium, and India). Participants represented government regulatory, commercial testing, university, research institute, and private laboratories. The single-laboratory validated (SLV) tea method was evaluated in the collaborative study to determine the recovery and reproducibility of the method under multilaboratory conditions. Since there were no restrictions regarding the type of analytical instrumentation to use for the analyses, laboratories used a combination of equipment that included GC/MS, GC/MS/MS, and LC/MS/MS instruments from 22 different manufacturers, 21 brands of GC and LC columns, 13 different GC temperature programming profiles, 11 LC gradient elution programs, and six different vendor manufactured SPE cartridges. Even though all the analytical performance parameters for all the 653 compounds had been determined in the SLV study, guidance was obtained from an expert review panel of the AOAC Method-Centric Committee on Pesticide Residues to conduct the multilaboratory collaborative study based on 20 selected compounds that can be analyzed by GC/MS and 20 compounds that can be analyzed by LC/MS/MS. Altogether, 560 samples covering the 40 selected pesticides were analyzed in the study. These samples included green tea and oolong tea samples fortified typically at the European Union maximum residue limit for regulatory guidance and compliance, aged tea samples incurred with 20 pesticides, and green tea and oolong tea samples incurred with five pesticides. The analysis of the 560 samples generated a total of 82 459 test results by the 30 participating laboratories. One laboratory failed to meet the proficiency requirements in the precollaborative study. Therefore, its data submitted for the collaborative study were excluded from further analysis and interpretation. The results presented are therefore the 6638 analytical results obtained from the 29 remaining laboratories, which included 1977 results generated by GC/MS, 1704 results by GC/MS/MS, and 2957 results by LC/MS/MS. It was determined after application of the Grubbs and Dixon tests for outliers to the data sets that there were 65 outlier results from the 1977 GC/MS results (3.3%), 65 outlier results from the 1704 GC/MS/MS results (3.8%), and 57 outlier results out of 2957 LC/MS/MS results (1.9%), representing 0.98, 0.98, and 0.86%, respectively, of the 6638 results generated in the study. Analysis with the AOAC statistical software package also confirmed that the method is rugged, and average recovery, average concentration, RSDr, RSDR, and HorRat values all meet recovery and reproducibility criteria for use in multiple laboratories. The Study Director is recommending this method for adoption as an AOAC First Action Official MethodSM.


Assuntos
Cromatografia Líquida/normas , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/normas , Chá/química , Cromatografia Líquida/instrumentação , Cromatografia Líquida/métodos , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Cooperação Internacional , Laboratórios/normas , Ensaio de Proficiência Laboratorial , Resíduos de Praguicidas/classificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
20.
Fitoterapia ; 106: 141-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26347952

RESUMO

Two new triterpenes (1 and 2) and two new triterpene glycosides (3 and 4), along with six known triterpenes (5-10) were isolated from the leaves of Ilex latifolia. The structures of new compounds were elucidated on the basis of NMR, HR-MS, and X-ray diffraction analysis. Compounds 4 and 5 showed potent inhibitory activity on oleic acid/palmitic acid induced triglyceride accumulation on HepG2 cells.


Assuntos
Glicosídeos/química , Ilex/química , Triglicerídeos/metabolismo , Triterpenos/química , Células Hep G2 , Humanos , Estrutura Molecular , Ácido Oleico , Ácido Palmítico , Folhas de Planta/química
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