Quadruple high-resolution α-glucosidase/α-amylase/PTP1B/radical scavenging profiling combined with high-performance liquid chromatography – high-resolution mass spectrometry – solid-phase extraction – nuclear magnetic resonance spectroscopy for identification of antidiabetic constituents in crude root bark of Morus alba L.

TY - JOUR

T1 - Quadruple high-resolution α-glucosidase/α-amylase/PTP1B/radical scavenging profiling combined with high-performance liquid chromatography – high-resolution mass spectrometry – solid-phase extraction – nuclear magnetic resonance spectroscopy for identification of antidiabetic constituents in crude root bark of Morus alba L.

AU - Zhao, Yong

AU - Kongstad, Kenneth Thermann

AU - Jäger, Anna K

AU - Nielsen, John

AU - Stærk, Dan

PY - 2018/6/29

Y1 - 2018/6/29

N2 - In this paper, quadruple high-resolution α-glucosidase/α-amylase/PTP1B/radical scavenging profiling combined with HPLC-HRMS-SPE-NMR were used for studying the polypharmacological properties of crude root bark extract of Morus alba L. This species is used as an anti-diabetic principle in many traditional treatment systems around the world, and the crude ethyl acetate extract of M. alba root bark was found to inhibit α-glucosidase, α-amylase and protein-tyrosine phosphatase 1B (PTP1B) with IC50 values of 1.70 ± 0.72, 5.16 ± 0.69, and 5.07 ± 0.68 μg/mL as well as showing radical scavenging activity equaling a TEAC value of (3.82 ± 0.14) × 104 mM per gram extract. Subsequent investigation of the crude extract using quadruple high-resolution α-glucosidase/α-amylase/PTP1B/radical scavenging profiling provided a quadruple biochromatogram that allowed direct correlation of the HPLC peaks with one or more of the tested bioactivities. This was used to target subsequent HPLC-HRMS-SPE-NMR analysis towards peaks representing bioactive analytes, and led to identification of a new Diels-Alder adduct named Moracenin E as well as a series of Diels-Alder adducts and isoprenylated flavonoids as potent α-glucosidase and α-amylase inhibitors with IC50 values in the range of 0.60–27.15 μM and 1.22–69.38 μM, respectively. In addition, these compounds and two 2-arylbenzofurans were found to be potent PTP1B inhibitors with IC50 values ranging from 4.04 to 21.67 μM. The high-resolution radical scavenging profile also revealed that almost all of the compounds possess radical scavenging activity. In conclusion the quadruple high-resolution profiling method presented here allowed a detailed profiling of individual constituents in crude root bark extract of M. alba, and the method provides a general tool for detailed mapping of bioactive constituents in polypharmacological herbal remedies.

AB - In this paper, quadruple high-resolution α-glucosidase/α-amylase/PTP1B/radical scavenging profiling combined with HPLC-HRMS-SPE-NMR were used for studying the polypharmacological properties of crude root bark extract of Morus alba L. This species is used as an anti-diabetic principle in many traditional treatment systems around the world, and the crude ethyl acetate extract of M. alba root bark was found to inhibit α-glucosidase, α-amylase and protein-tyrosine phosphatase 1B (PTP1B) with IC50 values of 1.70 ± 0.72, 5.16 ± 0.69, and 5.07 ± 0.68 μg/mL as well as showing radical scavenging activity equaling a TEAC value of (3.82 ± 0.14) × 104 mM per gram extract. Subsequent investigation of the crude extract using quadruple high-resolution α-glucosidase/α-amylase/PTP1B/radical scavenging profiling provided a quadruple biochromatogram that allowed direct correlation of the HPLC peaks with one or more of the tested bioactivities. This was used to target subsequent HPLC-HRMS-SPE-NMR analysis towards peaks representing bioactive analytes, and led to identification of a new Diels-Alder adduct named Moracenin E as well as a series of Diels-Alder adducts and isoprenylated flavonoids as potent α-glucosidase and α-amylase inhibitors with IC50 values in the range of 0.60–27.15 μM and 1.22–69.38 μM, respectively. In addition, these compounds and two 2-arylbenzofurans were found to be potent PTP1B inhibitors with IC50 values ranging from 4.04 to 21.67 μM. The high-resolution radical scavenging profile also revealed that almost all of the compounds possess radical scavenging activity. In conclusion the quadruple high-resolution profiling method presented here allowed a detailed profiling of individual constituents in crude root bark extract of M. alba, and the method provides a general tool for detailed mapping of bioactive constituents in polypharmacological herbal remedies.

U2 - 10.1016/j.chroma.2018.04.041

DO - 10.1016/j.chroma.2018.04.041

M3 - Journal article

C2 - 29729863

SN - 0021-9673

VL - 1556

SP - 55

EP - 63

JO - Journal of Chromatography A

JF - Journal of Chromatography A

ER -