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Daijie Wang - One of the best experts on this subject based on the ideXlab platform.

  • preparative isolation and purification of capsaicinoids from Capsicum Frutescens using high speed counter current chromatography
    Separation and Purification Technology, 2009
    Co-Authors: Yunliang Lin, Xiao Wang, Yanling Geng, Daijie Wang
    Abstract:

    Abstract Preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and purification of capsaicinoids from an extract of Capsicum Frutescens with a two-phase solvent system composed of tetrachloromethane–methanol–water at an optimized volume ratio of 4:3:2 (v/v/v). The lower phase was used as the mobile phase in the head to tail elution mode. The preparative HSCCC separation was performed on 150 mg of the crude extract yielding pure dihydrocapsaicin (33 mg), capsaicin (68 mg), and nordihydrocapsaicin (4 mg) at purities of 97.4%, 99.0% and 94.5%, respectively. The structures of the three compounds have been identified by MS, 1H NMR and 13C NMR.

Lijuan Chen - One of the best experts on this subject based on the ideXlab platform.

  • preparative separation of capsaicin and dihydrocapsaicin from Capsicum Frutescens by high speed counter current chromatography
    IEEE Journal of Solid-state Circuits, 2009
    Co-Authors: Aihua Peng, Lijuan Chen
    Abstract:

    Capsaicin and dihydrocapsaicin are two main bioactive components of Capsicum Frutescens and are widely used as food additives and drugs in China and India. Due to their similarity in structures, isolation of capsaicin and dihydrocapsaicin with traditional methods such as silica gel column chromatography, normal-phase thin-layer chromatography (TLC) becomes difficult. This study involves separating capsaicin and dihydrocapsaicin with sufficient purity and recovery using high-speed counter-current chromatography (HSCCC) with a solvent system composed of n-hexane-ethyl acetate-methanol-water-acetic acid (20:20:20:20:2, v/v/v/v/v). Separation parameters such as sample volume, and sample concentration were first optimized on analytical HSCCC, and then scaled up to preparative HSCCC. 0.65 g capsaicin and 0.28 g dihydrocapsaicin were obtained from 1.2 g crude extract and their purities were 98.5 and 97.8%, respectively. The recoveries of the two compounds were 86.3 and 85.4%, respectively. The purity of the isolated compounds was analyzed by high-performance liquid chromatography (HPLC) and their structures were identified by (1)H nuclear magnetic resonance (NMR) and (13)C NMR analysis.

Yunliang Lin - One of the best experts on this subject based on the ideXlab platform.

  • preparative isolation and purification of capsaicinoids from Capsicum Frutescens using high speed counter current chromatography
    Separation and Purification Technology, 2009
    Co-Authors: Yunliang Lin, Xiao Wang, Yanling Geng, Daijie Wang
    Abstract:

    Abstract Preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and purification of capsaicinoids from an extract of Capsicum Frutescens with a two-phase solvent system composed of tetrachloromethane–methanol–water at an optimized volume ratio of 4:3:2 (v/v/v). The lower phase was used as the mobile phase in the head to tail elution mode. The preparative HSCCC separation was performed on 150 mg of the crude extract yielding pure dihydrocapsaicin (33 mg), capsaicin (68 mg), and nordihydrocapsaicin (4 mg) at purities of 97.4%, 99.0% and 94.5%, respectively. The structures of the three compounds have been identified by MS, 1H NMR and 13C NMR.

Aihua Peng - One of the best experts on this subject based on the ideXlab platform.

  • preparative separation of capsaicin and dihydrocapsaicin from Capsicum Frutescens by high speed counter current chromatography
    IEEE Journal of Solid-state Circuits, 2009
    Co-Authors: Aihua Peng, Lijuan Chen
    Abstract:

    Capsaicin and dihydrocapsaicin are two main bioactive components of Capsicum Frutescens and are widely used as food additives and drugs in China and India. Due to their similarity in structures, isolation of capsaicin and dihydrocapsaicin with traditional methods such as silica gel column chromatography, normal-phase thin-layer chromatography (TLC) becomes difficult. This study involves separating capsaicin and dihydrocapsaicin with sufficient purity and recovery using high-speed counter-current chromatography (HSCCC) with a solvent system composed of n-hexane-ethyl acetate-methanol-water-acetic acid (20:20:20:20:2, v/v/v/v/v). Separation parameters such as sample volume, and sample concentration were first optimized on analytical HSCCC, and then scaled up to preparative HSCCC. 0.65 g capsaicin and 0.28 g dihydrocapsaicin were obtained from 1.2 g crude extract and their purities were 98.5 and 97.8%, respectively. The recoveries of the two compounds were 86.3 and 85.4%, respectively. The purity of the isolated compounds was analyzed by high-performance liquid chromatography (HPLC) and their structures were identified by (1)H nuclear magnetic resonance (NMR) and (13)C NMR analysis.

Ortolan, Silvio Augusto - One of the best experts on this subject based on the ideXlab platform.

  • Determinação da atividade antioxidante das matrizes vegetais Capsicum chinense, Capsicum Frutescens e Tripodanthus acutifolius
    2019
    Co-Authors: Ortolan, Silvio Augusto, Hermes, Vanessa Stahl, Pedroso, Pâmela Silveira, Leal, Valéria Louzada, Tischer Bruna, Possuelo, Lia Gonçalves, Silva, Chana De Medeiros Da
    Abstract:

    Radicais livres podem gerar estresse oxidativo e causar danos celulares. O uso de antioxidantes naturais demonstram ser um importante mecanismo para retardar ou inibir esse processo de oxidação. Matrizes vegetais dos gêneros Capsicum e Tripodanthus apresentam metabólitos secundários com atividade antioxidante relatada. Foi avaliada a atividade antioxidante de oleoresinas das pimentas Capsicum chinense e Capsicum Frutescens, e do extrato bruto da espécie Tripodanthus acutifolius, através do ensaio Oxygen Radical Absorbance Capacity (ORAC). As oleoresinas de C. chinense e C. Frutescens apresentaram valores de 550,210 μmol TE/g amostra e 603,746 μmol TE/g amostra, respectivamente. A espécie T. acutifolius apresentou valores aproximadamente dez vezes superiores (5277,764 μmol TE/g amostra) às oleoresinas. Observou-se uma relação direta da presença de compostos fenólicos com a atividade antioxidante. O ensaio realizado pelo grupo de pesquisas gerou um procedimento operacional interno que pode ser seguido em novas pesquisas de interesse com matrizes vegetais, aprovado para utilização no Parque Científico e Tecnológico Regional da Universidade de Santa Cruz do Sul (TecnoUnisc).Free radicals can generate oxidative stress and cause cell damage. The use of natural antioxidants evidences to be an important mechanism to delay or inhibit this oxidation process. Vegetable matrices of the genus Capsicum and Tripodanthus have secondary metabolites with reported antioxidant activity. The antioxidant activity of Capsicum chinense and Capsicum Frutescens oleoresins peppers and of the crude extract of Tripodanthus acutifolius was evaluated by the Oxygen Radical Absorbance Capacity (ORAC) assay. The samples C. chinense and C. Frutescens oleoresins presented values of 550,210 μmol TE/g and 603,746 μmol TE/g, respectively. The sample T. acutifolius presented values approximately ten times higher (5.277,764 μmol TE/g) to the oleoresins. It was observed a direct relation of the presence of phenolic compounds with the antioxidant activity. The research conducted by this group generated an internal operating procedure that can be adopt in new researches of interest with plant matrices. This document was approved for use in the Regional Scientific and Technological Park of the University of Santa Cruz do Sul (TecnoUnisc)

  • Determinação da atividade antioxidante das matrizes vegetais Capsicum chinense, Capsicum Frutescens e Tripodanthus acutifolius
    'APESC - Associacao Pro-Ensino em Santa Cruz do Sul', 2019
    Co-Authors: Ortolan, Silvio Augusto, Pedroso, Pâmela Silveira, Leal, Valéria Louzada, Tischer Bruna, Possuelo, Lia Gonçalves, Hermes, Vanessa Caroline, Da Silva, Chana De Medeiros
    Abstract:

    Radicais livres podem gerar estresse oxidativo e causar danos celulares. O uso de antioxidantes naturais demonstram ser um importante mecanismo para retardar ou inibir esse processo de oxidação. Matrizes vegetais dos gêneros Capsicum e Tripodanthus apresentam metabólitos secundários com atividade antioxidante relatada. Foi avaliada a atividade antioxidante de oleoresinas das pimentas Capsicum chinense e Capsicum Frutescens, e do extrato bruto da espécie Tripodanthus acutifolius, através do ensaio Oxygen Radical Absorbance Capacity (ORAC). As oleoresinas de C. chinense e C. Frutescens apresentaram valores de 550,210 µmol TE/g amostra e 603,746 µmol TE/g amostra, respectivamente. A espécie T. acutifolius apresentou valores aproximadamente dez vezes superiores (5277,764 µmol TE/g amostra) às oleoresinas. Observou-se uma relação direta da presença de compostos fenólicos com a atividade antioxidante. O ensaio realizado pelo grupo de pesquisas gerou um procedimento operacional interno que pode ser seguido em novas pesquisas de interesse com matrizes vegetais, aprovado para utilização no Parque Científico e Tecnológico Regional da Universidade de Santa Cruz do Sul (TecnoUnisc)