The Experts below are selected from a list of 15678 Experts worldwide ranked by ideXlab platform
Dan Staerk - One of the best experts on this subject based on the ideXlab platform.
-
dual high resolution α glucosidase and radical scavenging profiling combined with hplc hrms spe nmr for identification of minor and major constituents directly from the Crude extract of pueraria lobata
Journal of Natural Products, 2015Co-Authors: Kenneth Thermann Kongstad, Nils T Nyberg, Sun Qinglei, Anna K. Jäger, Dan StaerkAbstract:The Crude Methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the Crude extract without preceding purification was facilitated by combining chromatograms from two analytical-scale HPLC separations of 120 and 600 μg on-column, respectively. High-resolution α-glucosidase and radical scavenging profiles were obtained after microfractionation of the eluate in 96-well microplates. This allowed full bioactivity profiling of individual peaks in the HPLC chromatogram of the Crude Methanol extract. Subsequent HPLC-HRMS-SPE-NMR analysis allowed identification of 21 known compounds in addition to two new compounds, i.e., 3′-methoxydaidzein 8-C-[α-d-apiofuranosyl-(1→6)]-β-d-glucopyranoside and 6″-O-malonyl-3′-methoxydaidzin, as well as an unstable compound tentatively identified as 3′-de-O-methylpuerariafuran.
-
Dual High-Resolution α‑Glucosidase and Radical Scavenging Profiling Combined with HPLC-HRMS-SPE-NMR for Identification of Minor and Major Constituents Directly from the Crude Extract of Pueraria lobata
2015Co-Authors: Bingrui Liu, Nils T Nyberg, Sun Qinglei, Kenneth Thermann Kongstad, Anna K. Jäger, Dan StaerkAbstract:The Crude Methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the Crude extract without preceding purification was facilitated by combining chromatograms from two analytical-scale HPLC separations of 120 and 600 μg on-column, respectively. High-resolution α-glucosidase and radical scavenging profiles were obtained after microfractionation of the eluate in 96-well microplates. This allowed full bioactivity profiling of individual peaks in the HPLC chromatogram of the Crude Methanol extract. Subsequent HPLC-HRMS-SPE-NMR analysis allowed identification of 21 known compounds in addition to two new compounds, i.e., 3′-methoxydaidzein 8-C-[α-d-apiofuranosyl-(1→6)]-β-d-glucopyranoside and 6″-O-malonyl-3′-methoxydaidzin, as well as an unstable compound tentatively identified as 3′-de-O-methylpuerariafuran
Zahoor Ahmed - One of the best experts on this subject based on the ideXlab platform.
-
antioxidant and relaxant activity of fractions of Crude Methanol extract and essential oil of artemisia macrocephala jacquem
BMC Complementary and Alternative Medicine, 2013Co-Authors: Ismail Shah, Syed Wadood Ali Shah, Ghayour Ahmed, Mohammad Shoaib, Muhammad Junaid, Zahoor AhmedAbstract:Background The current work is an attempt to know about additional chemical profile of Artemisia macrocephala. Antioxidant activity is performed as the plant is reported to contain flavonoids, which have antioxidant activity in general. Relaxant activity of fractions of Crude Methanol extract is performed to know in which fraction(s) the relaxant constituents concentrate as we have already reported that its Crude Methanol has relaxant activity. Antispasmodic activity of essential oil is also performed as the plant is rich with essential oil.
-
antioxidant and relaxant activity of fractions of Crude Methanol extract and essential oil of artemisia macrocephala jacquem
BMC Complementary and Alternative Medicine, 2013Co-Authors: Niaz Ali, Ismail Shah, Syed Wadood Ali Shah, Ghayour Ahmed, Mohammad Shoaib, Muhammad Junaid, Waqar Ali, Zahoor AhmedAbstract:The current work is an attempt to know about additional chemical profile of Artemisia macrocephala. Antioxidant activity is performed as the plant is reported to contain flavonoids, which have antioxidant activity in general. Relaxant activity of fractions of Crude Methanol extract is performed to know in which fraction(s) the relaxant constituents concentrate as we have already reported that its Crude Methanol has relaxant activity. Antispasmodic activity of essential oil is also performed as the plant is rich with essential oil. Phytochemical profile of the plant is performed. Free radical scavenging activity was performed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH). Relaxation activity tests of fractions and essential oil of Artemisia macrocephala were performed on sections of rabbits’ jejunum. Calcium chloride curves were constructed to investigate the mode of action of plant extracts and its essential oil. We detected carbohydrates, flavonoids and saponins in A. macrocephala. At concentration 0.005 mg/ml, free radical scavenging activity of ethyl acetate fraction was 121.5 ± 2.02% of ascorbic acid. n- hexane fraction relaxed spontaneous activity with EC50 0.74 ± 0.04 mg/ml. Essential oil relaxed spontaneous activity with EC50 0.8 ± 0.034 mg/ml. Chloroform and ethylacetate fractions relaxed both spontaneous and KCl-induced contractions suggesting its possible mode through calcium channels. Constructing calcium chloride curves, the test fractions showed a right shift in the EC50. Essential oil at concentration 0.1 mg/ml produced right shift with EC50 (log [Ca++]M) -2.08 ± 0.08 vs. control with EC50 -2.47 ± 0.07. The curve resembled the curves of verapamil, which caused a right shift at 0.1 μM, with EC50 -1.7 ±0.07 vs. control EC50 (log [Ca++]M) -2.45 ± 0.06. Crude Methanol and its fractions (ethyl acetate, chloroform and butanol) are rich sources of antioxidant constituents. The relaxing constituents following calcium channel blocking mechanisms are more concentrated in n-hexane, chloroform and ethyl acetate fractions that warrant isolation.
Niaz Ali - One of the best experts on this subject based on the ideXlab platform.
-
brine shrimp cytotoxicity of Crude Methanol extract and antispasmodic activity of α amyrin acetate from tylophora hirsuta wall
BMC Complementary and Alternative Medicine, 2013Co-Authors: Niaz AliAbstract:We have previously reported that aerial parts of Tylophora hirsuta have antispasmodic profile. The current work is an attempt for isolation of pharmacologically active compound(s) that contribute for its antispasmodic activity. Preliminary phytochemical screening for Crude Methanol extract of Tylophora hirsuta (Th.Cr) is performed. Brine shrimp cytotoxicity of Crude Methanol extract is performed. Column chromatography was used for isolation of compounds. Mass spectroscopy, H1 NMR and C13 NMR were used for structural determination of compounds. α-amyrin acetate was tried for possible spasmolytic activity in rabbit’s jejunal preparations and KCl-induced contractions. Th.Cr tested positive for saponins, alkaloids, flavonoids and terpenoids. Compound 1 was isolated as α-amyrin acetate. Compound 2 was heptaeicosanol. Crude Methanol extract tested positive for brine shrimp cytotoxicity with LC50 492.33± 8.08 mg/ml. Compound 1 tested positive for antispasmodic activity on spontaneous rabbits’ jejunum preparations with EC50 (60 ± 2) × 10-5M. The compound also tested positive on KCl induced contractions with EC50 (72 ± 3) × 10-5M. The present work confirms that α-amyrin acetate is has antispasmodic profile and the relaxant effect may be attributed to α-amyrin acetate which is a major compound.
-
antioxidant and relaxant activity of fractions of Crude Methanol extract and essential oil of artemisia macrocephala jacquem
BMC Complementary and Alternative Medicine, 2013Co-Authors: Niaz Ali, Ismail Shah, Syed Wadood Ali Shah, Ghayour Ahmed, Mohammad Shoaib, Muhammad Junaid, Waqar Ali, Zahoor AhmedAbstract:The current work is an attempt to know about additional chemical profile of Artemisia macrocephala. Antioxidant activity is performed as the plant is reported to contain flavonoids, which have antioxidant activity in general. Relaxant activity of fractions of Crude Methanol extract is performed to know in which fraction(s) the relaxant constituents concentrate as we have already reported that its Crude Methanol has relaxant activity. Antispasmodic activity of essential oil is also performed as the plant is rich with essential oil. Phytochemical profile of the plant is performed. Free radical scavenging activity was performed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH). Relaxation activity tests of fractions and essential oil of Artemisia macrocephala were performed on sections of rabbits’ jejunum. Calcium chloride curves were constructed to investigate the mode of action of plant extracts and its essential oil. We detected carbohydrates, flavonoids and saponins in A. macrocephala. At concentration 0.005 mg/ml, free radical scavenging activity of ethyl acetate fraction was 121.5 ± 2.02% of ascorbic acid. n- hexane fraction relaxed spontaneous activity with EC50 0.74 ± 0.04 mg/ml. Essential oil relaxed spontaneous activity with EC50 0.8 ± 0.034 mg/ml. Chloroform and ethylacetate fractions relaxed both spontaneous and KCl-induced contractions suggesting its possible mode through calcium channels. Constructing calcium chloride curves, the test fractions showed a right shift in the EC50. Essential oil at concentration 0.1 mg/ml produced right shift with EC50 (log [Ca++]M) -2.08 ± 0.08 vs. control with EC50 -2.47 ± 0.07. The curve resembled the curves of verapamil, which caused a right shift at 0.1 μM, with EC50 -1.7 ±0.07 vs. control EC50 (log [Ca++]M) -2.45 ± 0.06. Crude Methanol and its fractions (ethyl acetate, chloroform and butanol) are rich sources of antioxidant constituents. The relaxing constituents following calcium channel blocking mechanisms are more concentrated in n-hexane, chloroform and ethyl acetate fractions that warrant isolation.
Kenneth Thermann Kongstad - One of the best experts on this subject based on the ideXlab platform.
-
dual high resolution α glucosidase and radical scavenging profiling combined with hplc hrms spe nmr for identification of minor and major constituents directly from the Crude extract of pueraria lobata
Journal of Natural Products, 2015Co-Authors: Kenneth Thermann Kongstad, Nils T Nyberg, Sun Qinglei, Anna K. Jäger, Dan StaerkAbstract:The Crude Methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the Crude extract without preceding purification was facilitated by combining chromatograms from two analytical-scale HPLC separations of 120 and 600 μg on-column, respectively. High-resolution α-glucosidase and radical scavenging profiles were obtained after microfractionation of the eluate in 96-well microplates. This allowed full bioactivity profiling of individual peaks in the HPLC chromatogram of the Crude Methanol extract. Subsequent HPLC-HRMS-SPE-NMR analysis allowed identification of 21 known compounds in addition to two new compounds, i.e., 3′-methoxydaidzein 8-C-[α-d-apiofuranosyl-(1→6)]-β-d-glucopyranoside and 6″-O-malonyl-3′-methoxydaidzin, as well as an unstable compound tentatively identified as 3′-de-O-methylpuerariafuran.
-
Dual High-Resolution α‑Glucosidase and Radical Scavenging Profiling Combined with HPLC-HRMS-SPE-NMR for Identification of Minor and Major Constituents Directly from the Crude Extract of Pueraria lobata
2015Co-Authors: Bingrui Liu, Nils T Nyberg, Sun Qinglei, Kenneth Thermann Kongstad, Anna K. Jäger, Dan StaerkAbstract:The Crude Methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the Crude extract without preceding purification was facilitated by combining chromatograms from two analytical-scale HPLC separations of 120 and 600 μg on-column, respectively. High-resolution α-glucosidase and radical scavenging profiles were obtained after microfractionation of the eluate in 96-well microplates. This allowed full bioactivity profiling of individual peaks in the HPLC chromatogram of the Crude Methanol extract. Subsequent HPLC-HRMS-SPE-NMR analysis allowed identification of 21 known compounds in addition to two new compounds, i.e., 3′-methoxydaidzein 8-C-[α-d-apiofuranosyl-(1→6)]-β-d-glucopyranoside and 6″-O-malonyl-3′-methoxydaidzin, as well as an unstable compound tentatively identified as 3′-de-O-methylpuerariafuran
Ismail Shah - One of the best experts on this subject based on the ideXlab platform.
-
antioxidant and relaxant activity of fractions of Crude Methanol extract and essential oil of artemisia macrocephala jacquem
BMC Complementary and Alternative Medicine, 2013Co-Authors: Ismail Shah, Syed Wadood Ali Shah, Ghayour Ahmed, Mohammad Shoaib, Muhammad Junaid, Zahoor AhmedAbstract:Background The current work is an attempt to know about additional chemical profile of Artemisia macrocephala. Antioxidant activity is performed as the plant is reported to contain flavonoids, which have antioxidant activity in general. Relaxant activity of fractions of Crude Methanol extract is performed to know in which fraction(s) the relaxant constituents concentrate as we have already reported that its Crude Methanol has relaxant activity. Antispasmodic activity of essential oil is also performed as the plant is rich with essential oil.
-
antioxidant and relaxant activity of fractions of Crude Methanol extract and essential oil of artemisia macrocephala jacquem
BMC Complementary and Alternative Medicine, 2013Co-Authors: Niaz Ali, Ismail Shah, Syed Wadood Ali Shah, Ghayour Ahmed, Mohammad Shoaib, Muhammad Junaid, Waqar Ali, Zahoor AhmedAbstract:The current work is an attempt to know about additional chemical profile of Artemisia macrocephala. Antioxidant activity is performed as the plant is reported to contain flavonoids, which have antioxidant activity in general. Relaxant activity of fractions of Crude Methanol extract is performed to know in which fraction(s) the relaxant constituents concentrate as we have already reported that its Crude Methanol has relaxant activity. Antispasmodic activity of essential oil is also performed as the plant is rich with essential oil. Phytochemical profile of the plant is performed. Free radical scavenging activity was performed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH). Relaxation activity tests of fractions and essential oil of Artemisia macrocephala were performed on sections of rabbits’ jejunum. Calcium chloride curves were constructed to investigate the mode of action of plant extracts and its essential oil. We detected carbohydrates, flavonoids and saponins in A. macrocephala. At concentration 0.005 mg/ml, free radical scavenging activity of ethyl acetate fraction was 121.5 ± 2.02% of ascorbic acid. n- hexane fraction relaxed spontaneous activity with EC50 0.74 ± 0.04 mg/ml. Essential oil relaxed spontaneous activity with EC50 0.8 ± 0.034 mg/ml. Chloroform and ethylacetate fractions relaxed both spontaneous and KCl-induced contractions suggesting its possible mode through calcium channels. Constructing calcium chloride curves, the test fractions showed a right shift in the EC50. Essential oil at concentration 0.1 mg/ml produced right shift with EC50 (log [Ca++]M) -2.08 ± 0.08 vs. control with EC50 -2.47 ± 0.07. The curve resembled the curves of verapamil, which caused a right shift at 0.1 μM, with EC50 -1.7 ±0.07 vs. control EC50 (log [Ca++]M) -2.45 ± 0.06. Crude Methanol and its fractions (ethyl acetate, chloroform and butanol) are rich sources of antioxidant constituents. The relaxing constituents following calcium channel blocking mechanisms are more concentrated in n-hexane, chloroform and ethyl acetate fractions that warrant isolation.