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Brijesh Kumar - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of bioactive monoterpene indole alkaloids in ethanolic extract of seven Rauvolfia species using uhplc with hybrid triple quadrupole linear ion trap mass spectrometry
Phytochemical Analysis, 2016Co-Authors: Sunil Kumar, Brijesh Kumar, Awantika Singh, Vikas Bajpai, Mukesh Srivastava, Bhim Singh, Sanjeev Kumar OjhaAbstract:Introduction Rauvolfia serpentina is an endangered plant species due to its over-exploitation. It has highly commercial and economic importance due to the presence of bioactive monoterpene indole alkaloids (MIAs) such as ajmaline, yohimbine, ajmalicine, serpentine and reserpine. Objective To develop a validated, rapid, sensitive and selective ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole-linear ion trap mass spectrometry (UHPLC-QqQLIT-MS/MS) method in the multiple reaction monitoring (MRM) mode for simultaneous determination of bioactive MIAs in ethanolic extract of seven Rauvolfia species and herbal formulations. Methods The separation of MIAs was achieved on an ACQUITY UPLC BEH™ C18 column (1.7 μm, 2.1 mm × 50 mm) using a gradient mobile phase (0.1% aqueous formic acid and acetonitrile) at flow rate 0.3 μL/min in 7 min. The validated method showed good linearity (r2 ≥ 0.9999), limit of detection (LOD) (0.06–0.15 ng/mL), limit of quantitation (LOQ) (0.18–0.44 ng/mL), precisions [intraday: relative standard deviation (RSD) ≤ 2.24%, interday: RSD ≤ 2.74%], stability (RSD ≤ 1.53%) and overall recovery (RSD ≤ 2.23%). Results The validated method was applied to quantitate MIAs. Root of Rauvolfia vomitoria showed a high content of ajmaline (48.43 mg/g), serpentine (87.77 mg/g) whereas high quantities of yohimbine (100.21 mg/g) and ajmalicine (120.51 mg/g) were detected in R. tetraphylla. High content of reserpine was detected in R. micrantha (35.18 mg/g) and R. serpentina (32.38 mg/g). Conclusion The encouraging results of this study may lead to easy selection of suitable Rauvolfia species according to the abundance of MIAs. Copyright © 2016 John Wiley & Sons, Ltd.
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rapid fingerprinting of rauwolfia species using direct analysis in real time mass spectrometry combined with principal component analysis for their discrimination
Analytical Methods, 2015Co-Authors: Sunil Kumar, S Bindu, K B Rameshkumar, Brijesh Kumar, Awantika Singh, Vikas Bajpai, Mukesh SrivastavaAbstract:Medicinal plants of the genus Rauwolfia (Apocynaceae) are extensively used as folk medicines worldwide. Its antihypertensive activity is well known due to the presence of monoterpene indole alkaloids (MIAs). The therapeutic potential of the herbal medicines are affected due to variation of bioactive phytoconstituents. Therefore, a rapid and validated method was developed for fingerprinting of roots and leaves of six Rauwolfia species by direct analysis in real time mass spectrometry (DART-MS). Seventeen bioactive MIAs were tentatively identified on the basis of their exact mass measurement from the intact plant parts. Furthermore, principal component analysis (PCA) was used to analyze the DART-MS data of six Rauwolfia species to identify the chemical markers. Thirteen and twenty-three chemical markers were identified from the roots and leaves which were able to discriminate among six Rauwolfia species. This method was also cross-validated for the rapid identification, authentication and quality control of Rauwolfia species.
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distribution of reserpine in Rauvolfia species from india hptlc and lc ms studies
Industrial Crops and Products, 2014Co-Authors: S Bindu, K B Rameshkumar, Brijesh Kumar, Awantika Singh, C AnilkumarAbstract:a b s t r a c t Rauvolfia species are important medicinal plants due to the presence of bioactive indole alkaloids, especially reserpine. Reserpine content in the roots of six Rauvolfia species (R. hookeri, R. micran- tha, R. serpentina, R. tetraphylla, R. verticillata, and R. vomitoria), were detected by high performance liquid chromatography coupled with electrospray ionization quadrapole time of flight tandem mass spectrometry (HPLC-ESI-QToF-MS/MS) and estimated by validated high performance thin layer chro- matography (HPTLC) method. Reserpine has positively been identified in the crude alkaloid extracts through HPLC-ESI-QToF-MS/MS method by exact mass, isotopic peak pattern, tandem mass fragmen- tation pattern, and with authentic standard match. Excellent separation of reserpine was achieved in HPTLC using the solvent system hexane:acetone:methanol (6:3.5:0.5, v/v). The HPTLC estimation method was validated in terms of linearity, specificity, detection limit, quantitation limit, precision, accuracy, and repeatability. Among the six Rauvolfia species, reserpine content was highest in the exotic species R. vom- itoria (689.5 g/g, dry wt.), while among the five Indian species the highest reserpine content was for R. tetraphylla (450.7 g/g, dry wt.). In the most common Indian Rauvolfia species, R. serpentina, the reserpine content was comparatively low (254.8 g/g, dry wt.). The endemic species R. micrantha possesses signifi- cant quantity of reserpine (422.1 g/g, dry wt.), making it a potential candidate for developing as a source of reserpine, replacing R. serpentina and R. tetraphylla that are endangered due to over exploitation. © 2014 Elsevier B.V. All rights reserved.
Joachim Stockigt - One of the best experts on this subject based on the ideXlab platform.
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functional expression of an ajmaline pathway specific esterase from Rauvolfia in a novel plant virus expression system
Planta, 2005Co-Authors: Martin Ruppert, Jorn Woll, Anatoli Giritch, Ezzat Genady, Joachim StockigtAbstract:Acetylajmalan esterase (AAE) plays an essential role in the late stage of ajmaline biosynthesis. Based on the partial peptide sequences of AAE isolated and purified from Rauvolfia cell suspensions, a full-length AAE cDNA clone was isolated. The amino acid sequence of AAE has the highest level of identity of 40% to putative lipases known from the Arabidopsis thaliana genome project. Based on the primary structure AAE is a new member of the GDSL lipase superfamily. The expression in Escherichia coli failed although a wide range of conditions were tested. With a novel virus-based plant expression system, it was possible to express AAE functionally in leaves of Nicotiana benthamiana Domin. An extraordinarily high enzyme activity was detected in the Nicotiana tissue, which exceeded that in Rauvolfia serpentina (L.) Benth. ex Kurz cell suspension cultures about 20-fold. This expression allowed molecular analysis of AAE for the first time and increased the number of functionally expressed alkaloid genes from Rauvolfia now to eight, and the number of ajmaline pathway-specific cDNAs to a total of six.
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vomilenine reductase a novel enzyme catalyzing a crucial step in the biosynthesis of the therapeutically applied antiarrhythmic alkaloid ajmaline
Bioorganic & Medicinal Chemistry, 2002Co-Authors: Gerald Von Schumann, Joachim StockigtAbstract:Abstract Delineation of the biochemical pathway leading to the antiarrhythmic Rauvolfia alkaloid ajmaline has been an important target in biosynthetic research for many years. The biosynthetic sequence starting with tryptamine and the monoterpene secologanin consists of about 10 different steps. Most of the participating enzymes have been detected and characterized previously, except those catalyzing the reduction of the intermediate vomilenine. A novel NADPH-dependent enzyme that reduces the intermediate has been isolated from Rauvolfia serpentina cell suspension cultures. Vomilenine reductase (M r 43 kDa, temp opt 30 °C, pH opt 5.7–6.2), saturates the indolenine double bond of vomilenine with stereospecific formation of 2β( R )-1,2-dihydrovomilenine. The described detection, enrichment and properties of the reductase not only closes a gap in ajmaline biosynthesis but is also a prerequisite for overexpressing the protein heterologously for final clarification of its molecular properties.
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3 oxo rhazinilam a new indole alkaloid from Rauvolfia serpentina rhazya stricta hybrid plant cell cultures
Journal of Natural Products, 2001Co-Authors: Irina Gerasimenko, Y. V. Sheludko, Joachim StockigtAbstract:A new monoterpenoid indole alkaloid, 3-oxo-rhazinilam (1), was isolated from intergeneric somatic hybrid cell cultures of Rauvolfia serpentina and Rhazya stricta, and the structure was determined by detailed 1D and 2D NMR analysis. It was also proved that 3-oxo-rhazinilam (1) is a natural constituent of the hybrid cells.
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chapter 2 biosynthesis in rauwolfia serpentina modern aspects of an old medicinal plant
The Alkaloids: Chemistry and Pharmacology, 1995Co-Authors: Joachim StockigtAbstract:Publisher Summary This chapter discusses a research on Rauwolfia , which was achieved after the generation of a cell suspension with extraordinary growth characteristics and physiological behavior. The investigations demonstrated that a range of techniques is now available for the clarification of complete metabolic pathways, provided that the appropriate efficient biological system is available. The isolation and identification of each single enzyme have almost become routine, even if an extremely sensitive protein analytic technique is necessary when several kilograms of fresh plant cells are reduced to a few micrograms of homogenous protein. The successful identification of a total of 20 novel enzyme activities catalyzing particular steps in Rauwolfia alkaloid biosynthesis allows the designing of research on the regulation of biochemical sequences and the isolation and characterization of the genes involved. The future application of noninvasive techniques, such as in vivo NMR, is also expected to produce a closer insight into the cell chemistry of Rauwolfia . For all of these future aspects the cell suspension culture of R. serpentine described in the chapter is a valuable research tool.
Awantika Singh - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of bioactive monoterpene indole alkaloids in ethanolic extract of seven Rauvolfia species using uhplc with hybrid triple quadrupole linear ion trap mass spectrometry
Phytochemical Analysis, 2016Co-Authors: Sunil Kumar, Brijesh Kumar, Awantika Singh, Vikas Bajpai, Mukesh Srivastava, Bhim Singh, Sanjeev Kumar OjhaAbstract:Introduction Rauvolfia serpentina is an endangered plant species due to its over-exploitation. It has highly commercial and economic importance due to the presence of bioactive monoterpene indole alkaloids (MIAs) such as ajmaline, yohimbine, ajmalicine, serpentine and reserpine. Objective To develop a validated, rapid, sensitive and selective ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole-linear ion trap mass spectrometry (UHPLC-QqQLIT-MS/MS) method in the multiple reaction monitoring (MRM) mode for simultaneous determination of bioactive MIAs in ethanolic extract of seven Rauvolfia species and herbal formulations. Methods The separation of MIAs was achieved on an ACQUITY UPLC BEH™ C18 column (1.7 μm, 2.1 mm × 50 mm) using a gradient mobile phase (0.1% aqueous formic acid and acetonitrile) at flow rate 0.3 μL/min in 7 min. The validated method showed good linearity (r2 ≥ 0.9999), limit of detection (LOD) (0.06–0.15 ng/mL), limit of quantitation (LOQ) (0.18–0.44 ng/mL), precisions [intraday: relative standard deviation (RSD) ≤ 2.24%, interday: RSD ≤ 2.74%], stability (RSD ≤ 1.53%) and overall recovery (RSD ≤ 2.23%). Results The validated method was applied to quantitate MIAs. Root of Rauvolfia vomitoria showed a high content of ajmaline (48.43 mg/g), serpentine (87.77 mg/g) whereas high quantities of yohimbine (100.21 mg/g) and ajmalicine (120.51 mg/g) were detected in R. tetraphylla. High content of reserpine was detected in R. micrantha (35.18 mg/g) and R. serpentina (32.38 mg/g). Conclusion The encouraging results of this study may lead to easy selection of suitable Rauvolfia species according to the abundance of MIAs. Copyright © 2016 John Wiley & Sons, Ltd.
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rapid fingerprinting of rauwolfia species using direct analysis in real time mass spectrometry combined with principal component analysis for their discrimination
Analytical Methods, 2015Co-Authors: Sunil Kumar, S Bindu, K B Rameshkumar, Brijesh Kumar, Awantika Singh, Vikas Bajpai, Mukesh SrivastavaAbstract:Medicinal plants of the genus Rauwolfia (Apocynaceae) are extensively used as folk medicines worldwide. Its antihypertensive activity is well known due to the presence of monoterpene indole alkaloids (MIAs). The therapeutic potential of the herbal medicines are affected due to variation of bioactive phytoconstituents. Therefore, a rapid and validated method was developed for fingerprinting of roots and leaves of six Rauwolfia species by direct analysis in real time mass spectrometry (DART-MS). Seventeen bioactive MIAs were tentatively identified on the basis of their exact mass measurement from the intact plant parts. Furthermore, principal component analysis (PCA) was used to analyze the DART-MS data of six Rauwolfia species to identify the chemical markers. Thirteen and twenty-three chemical markers were identified from the roots and leaves which were able to discriminate among six Rauwolfia species. This method was also cross-validated for the rapid identification, authentication and quality control of Rauwolfia species.
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distribution of reserpine in Rauvolfia species from india hptlc and lc ms studies
Industrial Crops and Products, 2014Co-Authors: S Bindu, K B Rameshkumar, Brijesh Kumar, Awantika Singh, C AnilkumarAbstract:a b s t r a c t Rauvolfia species are important medicinal plants due to the presence of bioactive indole alkaloids, especially reserpine. Reserpine content in the roots of six Rauvolfia species (R. hookeri, R. micran- tha, R. serpentina, R. tetraphylla, R. verticillata, and R. vomitoria), were detected by high performance liquid chromatography coupled with electrospray ionization quadrapole time of flight tandem mass spectrometry (HPLC-ESI-QToF-MS/MS) and estimated by validated high performance thin layer chro- matography (HPTLC) method. Reserpine has positively been identified in the crude alkaloid extracts through HPLC-ESI-QToF-MS/MS method by exact mass, isotopic peak pattern, tandem mass fragmen- tation pattern, and with authentic standard match. Excellent separation of reserpine was achieved in HPTLC using the solvent system hexane:acetone:methanol (6:3.5:0.5, v/v). The HPTLC estimation method was validated in terms of linearity, specificity, detection limit, quantitation limit, precision, accuracy, and repeatability. Among the six Rauvolfia species, reserpine content was highest in the exotic species R. vom- itoria (689.5 g/g, dry wt.), while among the five Indian species the highest reserpine content was for R. tetraphylla (450.7 g/g, dry wt.). In the most common Indian Rauvolfia species, R. serpentina, the reserpine content was comparatively low (254.8 g/g, dry wt.). The endemic species R. micrantha possesses signifi- cant quantity of reserpine (422.1 g/g, dry wt.), making it a potential candidate for developing as a source of reserpine, replacing R. serpentina and R. tetraphylla that are endangered due to over exploitation. © 2014 Elsevier B.V. All rights reserved.
Moses B Ekong - One of the best experts on this subject based on the ideXlab platform.
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effect of crude ethanolic leaf extract of rauwolfia vomitoria on the fetal lungs of wistar rats
Egyptian Academic Journal of Biological Sciences D. Histology & Histochemistry, 2014Co-Authors: Mokutima A Eluwa, Theresa B Ekanem, Moses B Ekong, Amabe O Akpantah, Kenneth Osim, Ene E Effa, Agnes O NwakanmaAbstract:Article History Rauwolfia vomitoria is a plant used in the treatment of hypertension, schizophrenia, and insomnia among others. This study investigated the effects of Rauwolfia vomitoria on the histology of the fetal lungs. Fifteen female Wistar rats weighing 180-200 g were divided into three groups (A, B, and C), consisting of five rats each. The animals mated overnight at estrous and the morning after coitus was designated day zero of pregnancy. Oral doses of 150 mg/kg and 250 mg/kg of ethanolic leaf extract of Rauwolfia vomitoria were administered to pregnant rats in groups B and C, respectively on day 7-11 of gestation, while group A served as the control group and were given distilled water. On day 20 of gestation, the rats were sacrificed and their fetuses examined and weighed. Fetal body weight, crown-rump and tail lengths were measured. Result showed significant (P < 0.05) higher anthropometric parameters, and the histological observations of the fetal lungs showed marked distortion of the normal lung cytoarchitecture in the treated groups compared to the control. These results suggest that doses of 150 mg/kg and 250 mg/kg body weight of the leaf extract of Rauwolfia vomitoria may cause intrauterine growth acceleration and may be pneumotoxic to the developing rat's lungs with the effect being dose dependent
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teratogenic effects of crude ethanolic root bark and leaf extracts of rauwolfia vomitoria apocynaceae on the femur of albino wistar rat fetuses
Journal of Histology, 2013Co-Authors: Mokutima A Eluwa, Theresa B Ekanem, P B Udoh, Moses B Ekong, Amabe O Akpantah, O R Asuquo, Agnes O NwakanmaAbstract:Introduction. Rauwolfia vomitoria is a plant used as a sedative and in the treatment of psychotic tendency. This study was on the teratogenic effects of its root bark and leaf extracts on Wistar rat’s fetal femurs. Materials and Methods. Twenty-five female rats weighing between 180 and 200 g were divided into 5 groups, of 5 rats each. Group A was the control, while Groups B, C, D, and E were the experimental. The female rats were mated with mature male rats to allow for pregnancy. Groups B and C animals received orally 150 mg/kg each of the root bark and leaf extracts of Rauwolfia vomitoria, respectively, while Groups D and E animals received 250 mg/kg bodyweight each of the root bark and leaf extracts of Rauwolfia vomitoria, respectively, from day 7 to day 11 of gestation. On day 20 of gestation, the rats were sacrificed, the fetuses were examined, and their femurs were dissected out and preserved, decalcified, and routinely processed using the Haematoxylin and Eosin staining method. Results. Histological observations of the fetal femur bones showed numerous osteoblast and osteoclast, hypertrophy, and hyperplasia of bone cells compared with the control. Conclusion. Ethanolic root bark and leaf extracts of Rauwolfia vomitoria may lead to advanced skeletal development.
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comparative study of teratogenic potentials of crude ethanolic root bark and leaf extract of rauwolfia vomitoria apocynaceae on the fetal heart
North American Journal of Medical Sciences, 2010Co-Authors: Mokutima A Eluwa, Theresa B Ekanem, Amabe O Akpantah, O R Asuquo, Matilda T Udoaffah, Moses B G Vulley, Moses B EkongAbstract:Background : Rauwolfia vomitoria , a tropical shrub, is a medicinal plant used in the treatment of a variety of ailments. It is popular to the locals because of its anti-hypertensive and sedative properties. Aim : This is to find the probable teratogenic effects of ethanolic leaf and root bark extracts of Rauwolfia vomitoria on the morphological and histological features of the fetal heart. Material and Methods: Twenty five female rats weighing between 170-200g were used for this study. The rats were divided into five groups labeled A, B, C, D and E, with each group consisting of five rats. Pregnancy was induced by caging the female rats with sexually matured males. The presence of vaginal plug and tail structures in the vaginal smear the following morning confirmed coition, and it was regarded as day 0 of pregnancy. Group A was given sham treatment of distilled water. Group B and C received respectively 150mg/kg and 250mg/kg body weight doses of ethanolic leaf extract of Rauwolfia vomitoria, and those in groups D and E received respectively 150mg/kg and 250mg/kg body weight doses of ethanolic root bark extract of Rauwolfia vomitoria. These treatments were on days 7-11 of gestation (5 days) with the aid of an orogastric tube. On the day 20 of gestation, the rats were sacrificed and the fetuses examined for gross anomalies, preserved and latter process for histological studies. Results : There were no mortality in this study, and no obvious gross malformations in the fetuses. Histological observations of the fetal heart showed marked distortion of the cardiac muscle nuclei and myocardial fibers in the treated groups particularly those whose mothers received 250mg/kg of the extracts. These effects were more pronounced in the groups whose mothers received the root extract when compared with the control and the groups whose mothers received the leaf extract. Conclusion : This result suggests that high doses of ethanolic leaf and root extracts of Rauwolfia vomitoria may be cardiotoxic to the developing rat's heart.
Ufot Usenobong Friday - One of the best experts on this subject based on the ideXlab platform.
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vitamin e supplementation with rauwolfia vomitoria root bark extract improves hematological indices
North American Journal of Medical Sciences, 2012Co-Authors: Akpanabiatu Monday Isaiah, Otitoju Olawale, Edet Emmanuel Effiong, Ndem Jessie Idongesit, Uwah Anthony Fidelis, Ufot Usenobong FridayAbstract:Background: Vitamin supplementation in Rauwolfia vomitoria root bark extract administration may interact and impact significantly on hematology of albino Wistar rats.
