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Thomas Efferth - One of the best experts on this subject based on the ideXlab platform.
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variation in contents of main active components and antioxidant activity in leaves of different Pigeon Pea cultivars during growth
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Zuofu Wei, Meng Luo, Shuang Jin, Youzhi Pan, Thomas EfferthAbstract:Pigeon Pea is an important and multiuse grain legume crop, and its leaves are a very valuable natural resource. To obtain a high-quality biological resource, it is necessary to choose the excellent...
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uv induced changes of active components and antioxidant activity in postharvest Pigeon Pea cajanus cajan l millsp leaves
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Zuofu Wei, Chunjian Zhao, Meng Luo, Wei Wang, Thomas EfferthAbstract:In this study, the effect of UV irradiation (UV-A, UV-B, and UV-C) on phytochemicals, total phenolics, and antioxidant activity of postharvest Pigeon Pea leaves was evaluated. The response of Pigeon Pea leaves to UV irradiation was phytochemical specific. UV-B and UV-C induced higher levels of phytochemicals, total phenolics, and antioxidant activity in Pigeon Pea leaves compared with UV-A. Furthermore, UV-B irradiation proved to possess a long-lasting effect on the levels of phenolics and antioxidant activity. After adapting for 48 h at 4 °C following 4 h UV-B irradiation, total phenolics and antioxidant activity were approximately 1.5-fold and 2.2-fold increased from 39.4 mg GAE/g DM and 15.0 μmol GAE/g DM to 59.1 mg GAE/g DM and 32.5 μmol GAE/g DM, respectively. These results indicate that UV irradiation of Pigeon Pea leaves can be beneficial in terms of increasing active components and antioxidant activity.
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resin adsorption as a means to enrich rare stilbenes and coumarin from Pigeon Pea leaves extracts
Chemical Engineering Journal, 2011Co-Authors: Zuofu Wei, Chunjian Zhao, Meng Luo, Wei Wang, Thomas EfferthAbstract:Abstract In this study, resin adsorption as a means to enrich rare stilbenes cajaninstilbene acid (CSA) and longistyline C (LLC), and coumarin cajanuslactone (CL) from Pigeon Pea leaves was investigated. Among widely used twenty macroporous adsorption resins, NKA-9 resin presented higher adsorption capacity and desorption ratio in static tests. The adsorption kinetic model fitted better depended on types of compounds and pH values. The experimental adsorption data were better fitted to Langmuir isotherm (R2 0.921–0.991) than Freundlich isotherm (R2 0.753–0.988). In order to optimize the operating parameters for separating CSA, LLC and CL, dynamic adsorption and desorption tests were carried out. After one run treatment with NKA-9 resin, the contents of CSA, LLC and CL in the product were 10.82-, 9.07- and 108.90-fold increased with recovery yields of 81.31%, 89.76% and 96.77%, respectively. Moreover, NKA-9 resin exhibited excellent reusability within at least five cycles of adsorption/desorption. The developed methodology is a promising basis for large-scale preparation of CSA, LLC and CL from Pigeon Pea leaves.
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negative pressure cavitation extraction for the determination of flavonoids in Pigeon Pea leaves by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Wei Liu, Yu Kong, Lin Zhang, Thomas EfferthAbstract:Abstract A new method, namely negative-pressure cavitation extraction (NPCE), followed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) is presented for the extraction and quantification of flavonoids in Pigeon Pea leaves. This method combines the high efficiency of NPCE and the sensitivity and accuracy of MS/MS. The influential parameters of the NPCE procedure including liquid/solid ratio, extraction time, nitrogen flow and number of extraction cycles were optimized. Under optimized conditions, the efficiency of NPCE for extracting five flavonoids was compared to microwave-assisted extraction (MAE), ultrasonic extraction (USE) and heating reflux extraction (HRE). Additionally, structural disruption to Pigeon Pea leaves samples with different extraction methods was investigated by scanning electron microscopy. The relative recovery with NPCE was equivalent to or higher than that with USE and obviously higher than those with MAE and HRE which are usually conducted in higher temperatures. Furthermore, because NPCE was performed with nitrogen at room temperature, the degradation and oxidation of analytes were avoided. In addition, the NPCE method was validated in terms of rePeatability and reproducibility, relative standard deviation for relative recovery was lower than 5.84 and 8.83%, respectively. The method was also successfully applied for the quantification of five flavonoids in Pigeon Pea leaves. All these results suggest that the developed NPCE-LC–MS/MS method represents an excellent alternative for the extraction and quantification of flavonoids in other plant materials.
D V R Reddy - One of the best experts on this subject based on the ideXlab platform.
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transmission of Pigeon Pea sterility mosaic virus by the eriophyid mite aceria cajani acari arthropoda
Plant Disease, 2002Co-Authors: N K Kulkarni, Lava P Kumar, V Muniyappa, Teifion A Jones, D V R ReddyAbstract:The transmission characteristics of Pigeon Pea sterility mosaic virus (PPSMV) to Pigeon Pea (Cajanus cajan) by its eriophyid mite vector, A. cajani, were studied. Nonviruliferous A. cajani colonies were established on detached healthy leaflets of a PPSMV-immune Pigeon Pea cultivar (ICP8863) floating on water. The transmission efficiency of single A. cajani was up to 53%, but was 100% when >5 mites per plant were used. A. cajani acquired PPSMV after a minimum acquisition access period (AAP) of 15 minutes and inoculated virus after a minimum inoculation access period (IAP) of 90 minutes. No latent period was observed. Starvation of A. cajani prior to, or following, PPSMV acquisition reduced the minimum AAP and IAP periods to 10 and 60 minutes, respectively, and mites retained virus for up to 13 h. None of the mites that developed from eggs taken from PPSMV-infected leaves transmitted the virus, indicating that it is not transmitted transovarially. Taken together, these data suggest a semipersistent mode of transmission of PPSMV by A. cajani.
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transmission of Pigeon Pea sterility mosaic virus by the eriophyid mite aceria cajani acari arthropoda
Plant Disease, 2002Co-Authors: N K Kulkarni, Lava P Kumar, V Muniyappa, Teifion A Jones, D V R ReddyAbstract:The transmission characteristics of Pigeon Pea sterility mosaic virus (PPSMV) to Pigeon Pea (Cajanus cajan) by its eriophyid mite vector, Aceria cajani, were studied. Nonviruliferous A. cajani colonies were established on detached healthy leaflets of a PPSMV-immune Pigeon Pea cultivar floating on water. The transmission efficiency of single A. cajani was up to 53% but was 100% when >5 mites per plant were used. A. cajani acquired PPSMV after a minimum acquisition access period (AAP) of 15 min and inoculated virus after a minimum inoculation access period (IAP) of 90 min. No latent period was observed. Starvation of A. cajani prior to, or following, PPSMV acquisition reduced the minimum AAP and IAP periods to 10 min and 60 min, respectively, and mites retained virus for up to 13 h. None of the mites that developed from eggs taken from PPSMV-infected leaves transmitted the virus, indicating that it is not transmitted transovarially. Taken together, these data suggest a semipersistent mode of transmission of PPSMV by A. cajani.
Wei Liu - One of the best experts on this subject based on the ideXlab platform.
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variation in contents of phenolic compounds during growth and post harvest storage of Pigeon Pea seedlings
Food Chemistry, 2010Co-Authors: Wei Liu, Yu Kong, Mei YangAbstract:Abstract The variation in contents of seven phenolic compounds in Pigeon Pea seedlings during growth and storage was investigated. Maximum contents of vitexin, isovitexin and orientin were found in leaves growing 40 days, which were 0.99 ± 0.06, 6.63 ± 0.35 and 30.89 ± 1.92 mg/g DW. Apigenin and luteolin were extensively distributed in leaves, stems and roots. Pinostrobin and cajaninstilbene acid were mainly accumulated in leaves, the Peak values 3.53 ± 0.18 and 2.49 ± 0.13 mg/g DW apPeared at the 60th day. Slight and steady increases of seven phenolic compounds were found in room temperature (25 °C) stored Pigeon Pea leaves up to 120 days. The highest accumulation of seven phenolic compounds at chilling temperature (4 °C) was observed at the 45th day, after which the contents decreased sharply. The stems extracts exhibited more efficient DPPH radical-scavenging ability while the roots extracts demonstrated the strongest lipid peroxidation inhibitory activity.
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determination and quantification of active phenolic compounds in Pigeon Pea leaves and its medicinal product using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2010Co-Authors: Wei Liu, Yu Kong, Meng Luo, Lin ZhangAbstract:A novel method using liquid chromatography coupled to electrospray ionization mass spectrometry (LC-ESI-MS) has been optimized and established for the qualitative and quantitative analysis of ten active phenolic compounds originating from the Pigeon Pea leaves and a medicinal product thereof (Tongluo Shenggu capsules). In the present study, the chromatographic separation was achieved by means of a HiQ Sil C18V reversed-phase column with a mobile phase consisting of methanol and 0.1% formic acid aqueous solution. Low-energy collision-induced dissociation tandem mass spectrometry (CID-MS/MS) using the selected reaction monitoring (SRM) analysis was employed for the detection of ten analytes which included six flavonoids, two isoflavonoids and two stilbenes. All calibration curves showed excellent coefficients of determination (r(2) ≥ 0.9937) within the range of tested concentrations. The intra- and inter-day variations were below 5.36% in terms of relative standard deviation (RSD). The recoveries were 95.08-104.98% with RSDs of 2.06-4.26% for spiked samples of Pigeon Pea leaves. The method developed was a rapid, efficient and accurate LC-MS/MS method for the detection of phenolic compounds, which can be applied for quality control of Pigeon Pea leaves and related medicinal products.
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preliminary enrichment and separation of genistein and apigenin from extracts of Pigeon Pea roots by macroporous resins
Bioresource Technology, 2010Co-Authors: Wei Liu, Su Zhang, Dongyang Zhang, Yu KongAbstract:Enrichment and separation of genistein and apigenin from extracts of Pigeon Pea roots were studied using eleven macroporous resins with different physical and chemical properties. ADS-5 resin showed the maximum effectiveness among the tested resins. The solute affinity towards ADS-5 resin at different temperatures was described in terms of Langmuir and Freundlich isotherms, and the equilibrium experimental data were well-fitted to the two isotherms. In order to optimize the operating parameters for separating genistein and apigenin, dynamic adsorption and desorption tests were carried out. After one run treatment with ADS-5 resin, the contents of genistein and apigenin in the product were 9.36-fold and 11.09-fold increased with recovery yields of 89.78% and 93.41%, respectively. The process achieved easy and effective enrichment and separation of genistein and apigenin by using ADS-5 resin, and it is a promising basis for large-scale preparation of genistein and apigenin from Pigeon Pea or other plants extracts.
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negative pressure cavitation extraction for the determination of flavonoids in Pigeon Pea leaves by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Wei Liu, Yu Kong, Lin Zhang, Thomas EfferthAbstract:Abstract A new method, namely negative-pressure cavitation extraction (NPCE), followed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) is presented for the extraction and quantification of flavonoids in Pigeon Pea leaves. This method combines the high efficiency of NPCE and the sensitivity and accuracy of MS/MS. The influential parameters of the NPCE procedure including liquid/solid ratio, extraction time, nitrogen flow and number of extraction cycles were optimized. Under optimized conditions, the efficiency of NPCE for extracting five flavonoids was compared to microwave-assisted extraction (MAE), ultrasonic extraction (USE) and heating reflux extraction (HRE). Additionally, structural disruption to Pigeon Pea leaves samples with different extraction methods was investigated by scanning electron microscopy. The relative recovery with NPCE was equivalent to or higher than that with USE and obviously higher than those with MAE and HRE which are usually conducted in higher temperatures. Furthermore, because NPCE was performed with nitrogen at room temperature, the degradation and oxidation of analytes were avoided. In addition, the NPCE method was validated in terms of rePeatability and reproducibility, relative standard deviation for relative recovery was lower than 5.84 and 8.83%, respectively. The method was also successfully applied for the quantification of five flavonoids in Pigeon Pea leaves. All these results suggest that the developed NPCE-LC–MS/MS method represents an excellent alternative for the extraction and quantification of flavonoids in other plant materials.
Yu Kong - One of the best experts on this subject based on the ideXlab platform.
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cajanuslactone a new coumarin with anti bacterial activity from Pigeon Pea cajanus cajan l millsp leaves
Food Chemistry, 2010Co-Authors: Yu Kong, Yuan-gang Zu, Yujie Fu, Fang Rong Chang, Yunghusan Chen, Johannes Stelten, Hansmartin SchiebelAbstract:Abstract The bioassay-guided fractionation of the CHCl 3 extract from Pigeon Pea leaves led to the isolation of a new natural coumarin, named as cajanuslactone ( 1 ), together with two known phytoalexins, pinostrobin ( 2 ) and cajaninstilbene acid ( 3 ). The structure of 1 was elucidated by interpreting spectroscopic data of UV, IR, MS, 1D and 2D NMR. It was determined as 7-hydroxy-5- O -methyl-8-(3-methyl-2-butylene)-4-phenyl-9,10-dihydro-benzopyran-2-one. The anti-bacterial activity against three Gram-positive microorganisms was evaluated in vitro . It was found the new compound cajanuslactone possessed good anti-bacterial activity against Staphylococcus aureus (ATCC 6538), and the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were 0.031 and 0.125 mg/ml, respectively. The result indicated that the leaf part of Pigeon Pea is an excellent source of natural anti-bacterial materials. Moreover, cajanuslactone is a potential anti-bacterial agent against Gram-positive microorganisms.
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variation in contents of phenolic compounds during growth and post harvest storage of Pigeon Pea seedlings
Food Chemistry, 2010Co-Authors: Wei Liu, Yu Kong, Mei YangAbstract:Abstract The variation in contents of seven phenolic compounds in Pigeon Pea seedlings during growth and storage was investigated. Maximum contents of vitexin, isovitexin and orientin were found in leaves growing 40 days, which were 0.99 ± 0.06, 6.63 ± 0.35 and 30.89 ± 1.92 mg/g DW. Apigenin and luteolin were extensively distributed in leaves, stems and roots. Pinostrobin and cajaninstilbene acid were mainly accumulated in leaves, the Peak values 3.53 ± 0.18 and 2.49 ± 0.13 mg/g DW apPeared at the 60th day. Slight and steady increases of seven phenolic compounds were found in room temperature (25 °C) stored Pigeon Pea leaves up to 120 days. The highest accumulation of seven phenolic compounds at chilling temperature (4 °C) was observed at the 45th day, after which the contents decreased sharply. The stems extracts exhibited more efficient DPPH radical-scavenging ability while the roots extracts demonstrated the strongest lipid peroxidation inhibitory activity.
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determination and quantification of active phenolic compounds in Pigeon Pea leaves and its medicinal product using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2010Co-Authors: Wei Liu, Yu Kong, Meng Luo, Lin ZhangAbstract:A novel method using liquid chromatography coupled to electrospray ionization mass spectrometry (LC-ESI-MS) has been optimized and established for the qualitative and quantitative analysis of ten active phenolic compounds originating from the Pigeon Pea leaves and a medicinal product thereof (Tongluo Shenggu capsules). In the present study, the chromatographic separation was achieved by means of a HiQ Sil C18V reversed-phase column with a mobile phase consisting of methanol and 0.1% formic acid aqueous solution. Low-energy collision-induced dissociation tandem mass spectrometry (CID-MS/MS) using the selected reaction monitoring (SRM) analysis was employed for the detection of ten analytes which included six flavonoids, two isoflavonoids and two stilbenes. All calibration curves showed excellent coefficients of determination (r(2) ≥ 0.9937) within the range of tested concentrations. The intra- and inter-day variations were below 5.36% in terms of relative standard deviation (RSD). The recoveries were 95.08-104.98% with RSDs of 2.06-4.26% for spiked samples of Pigeon Pea leaves. The method developed was a rapid, efficient and accurate LC-MS/MS method for the detection of phenolic compounds, which can be applied for quality control of Pigeon Pea leaves and related medicinal products.
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preliminary enrichment and separation of genistein and apigenin from extracts of Pigeon Pea roots by macroporous resins
Bioresource Technology, 2010Co-Authors: Wei Liu, Su Zhang, Dongyang Zhang, Yu KongAbstract:Enrichment and separation of genistein and apigenin from extracts of Pigeon Pea roots were studied using eleven macroporous resins with different physical and chemical properties. ADS-5 resin showed the maximum effectiveness among the tested resins. The solute affinity towards ADS-5 resin at different temperatures was described in terms of Langmuir and Freundlich isotherms, and the equilibrium experimental data were well-fitted to the two isotherms. In order to optimize the operating parameters for separating genistein and apigenin, dynamic adsorption and desorption tests were carried out. After one run treatment with ADS-5 resin, the contents of genistein and apigenin in the product were 9.36-fold and 11.09-fold increased with recovery yields of 89.78% and 93.41%, respectively. The process achieved easy and effective enrichment and separation of genistein and apigenin by using ADS-5 resin, and it is a promising basis for large-scale preparation of genistein and apigenin from Pigeon Pea or other plants extracts.
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negative pressure cavitation extraction for the determination of flavonoids in Pigeon Pea leaves by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Wei Liu, Yu Kong, Lin Zhang, Thomas EfferthAbstract:Abstract A new method, namely negative-pressure cavitation extraction (NPCE), followed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) is presented for the extraction and quantification of flavonoids in Pigeon Pea leaves. This method combines the high efficiency of NPCE and the sensitivity and accuracy of MS/MS. The influential parameters of the NPCE procedure including liquid/solid ratio, extraction time, nitrogen flow and number of extraction cycles were optimized. Under optimized conditions, the efficiency of NPCE for extracting five flavonoids was compared to microwave-assisted extraction (MAE), ultrasonic extraction (USE) and heating reflux extraction (HRE). Additionally, structural disruption to Pigeon Pea leaves samples with different extraction methods was investigated by scanning electron microscopy. The relative recovery with NPCE was equivalent to or higher than that with USE and obviously higher than those with MAE and HRE which are usually conducted in higher temperatures. Furthermore, because NPCE was performed with nitrogen at room temperature, the degradation and oxidation of analytes were avoided. In addition, the NPCE method was validated in terms of rePeatability and reproducibility, relative standard deviation for relative recovery was lower than 5.84 and 8.83%, respectively. The method was also successfully applied for the quantification of five flavonoids in Pigeon Pea leaves. All these results suggest that the developed NPCE-LC–MS/MS method represents an excellent alternative for the extraction and quantification of flavonoids in other plant materials.
N K Kulkarni - One of the best experts on this subject based on the ideXlab platform.
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transmission of Pigeon Pea sterility mosaic virus by the eriophyid mite aceria cajani acari arthropoda
Plant Disease, 2002Co-Authors: N K Kulkarni, Lava P Kumar, V Muniyappa, Teifion A Jones, D V R ReddyAbstract:The transmission characteristics of Pigeon Pea sterility mosaic virus (PPSMV) to Pigeon Pea (Cajanus cajan) by its eriophyid mite vector, A. cajani, were studied. Nonviruliferous A. cajani colonies were established on detached healthy leaflets of a PPSMV-immune Pigeon Pea cultivar (ICP8863) floating on water. The transmission efficiency of single A. cajani was up to 53%, but was 100% when >5 mites per plant were used. A. cajani acquired PPSMV after a minimum acquisition access period (AAP) of 15 minutes and inoculated virus after a minimum inoculation access period (IAP) of 90 minutes. No latent period was observed. Starvation of A. cajani prior to, or following, PPSMV acquisition reduced the minimum AAP and IAP periods to 10 and 60 minutes, respectively, and mites retained virus for up to 13 h. None of the mites that developed from eggs taken from PPSMV-infected leaves transmitted the virus, indicating that it is not transmitted transovarially. Taken together, these data suggest a semipersistent mode of transmission of PPSMV by A. cajani.
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transmission of Pigeon Pea sterility mosaic virus by the eriophyid mite aceria cajani acari arthropoda
Plant Disease, 2002Co-Authors: N K Kulkarni, Lava P Kumar, V Muniyappa, Teifion A Jones, D V R ReddyAbstract:The transmission characteristics of Pigeon Pea sterility mosaic virus (PPSMV) to Pigeon Pea (Cajanus cajan) by its eriophyid mite vector, Aceria cajani, were studied. Nonviruliferous A. cajani colonies were established on detached healthy leaflets of a PPSMV-immune Pigeon Pea cultivar floating on water. The transmission efficiency of single A. cajani was up to 53% but was 100% when >5 mites per plant were used. A. cajani acquired PPSMV after a minimum acquisition access period (AAP) of 15 min and inoculated virus after a minimum inoculation access period (IAP) of 90 min. No latent period was observed. Starvation of A. cajani prior to, or following, PPSMV acquisition reduced the minimum AAP and IAP periods to 10 min and 60 min, respectively, and mites retained virus for up to 13 h. None of the mites that developed from eggs taken from PPSMV-infected leaves transmitted the virus, indicating that it is not transmitted transovarially. Taken together, these data suggest a semipersistent mode of transmission of PPSMV by A. cajani.