TY - JOUR

T1 - Anti-obesity evaluation of Averrhoa carambola L. leaves and assessment of its polyphenols as potential α-glucosidase inhibitors

AU - Ramadan, Nehal S

AU - El-Sayed, Nabil H

AU - El-Toumy, Sayed A

AU - Mohamed, Doha Abdou

AU - Aziz, Zeinab Abdel

AU - Marzouk, Mohamed Sobhy

AU - Esatbeyoglu, Tuba

AU - Farag, Mohamed A

AU - Shimizu, Kuniyoshi

N1 - Funding information: The Egyptian Cultural Affairs and Missions sector, Ministry of Higher Education, Egypt, is acknowledged for the fellowship and financial support offered to N.S.R. This research was funded by a fellowship supported by the Egyptian Cultural Affairs and Missions sector, Ministry of Higher Education, Egypt. The publication of this article was funded by the Open Access Fund of Leibniz Universität Hannover.

PY - 2022/8/12

Y1 - 2022/8/12

N2 - Averrhoa carambola L. is reported for its anti-obese and anti-diabetic activities. The present study aimed to investigate its aqueous methanol leaf extract (CLL) in vivo anti-obese activity along with the isolation and identification of bioactive compounds and their in vitro α-glucosidase inhibition assessment. CLL improved all obesity complications and exhibited significant activity in an obese rat model. Fourteen compounds, including four flavone glycosides ( 1- 4) and ten dihydrochalcone glycosides ( 5- 12), were isolated and identified using spectroscopic techniques. New compounds identified in planta included ( 1) apigenin 6- C-(2-deoxy- β-D-galactopyranoside)-7- O- β-D-quinovopyranoside, ( 8) phloretin 3'- C-(2- O-( E)-cinnamoyl-3- O- β-D-fucopyranosyl-4- O-acetyl)- β-D-fucopyranosyl-6'- O- β-D fucopyranosyl-(1/2)-α-L arabinofuranoside, ( 11a) phloretin3'- C-(2- O-( E)-p-coumaroyl-3- O- β-D-fucosyl-4- O-acetyl)- β-D-fucosyl-6'- O-(2- O- β-D-fucosyl)-α-L-arabinofuranoside, ( 11b) phloretin3'- C-(2-O- (Z) -p-coumaroyl-3- O- β-D-fucosyl-4- O-acetyl)- β-D-fucosyl-6'- O-(2- O- β-D-fucosyl)-α-L-arabinofuranoside. Carambolaside M ( 5), carambolaside Ia ( 6), carambolaside J ( 7), carambolaside I ( 9), carambolaside P ( 10a), carambolaside O ( 10b), and carambolaside Q ( 12), which are reported for the first time from A. carambola L. leaves, whereas luteolin 6- C-α-L-rhamnopyranosyl-(1-2)- β-D-fucopyranoside ( 2), apigenin 6- C- β-D-galactopyranoside ( 3), and apigenin 6- C- α-L-rhamnopyranosyl-(1-2)- β-L-fucopyranoside ( 4) are isolated for the first time from Family. Oxalidaceae. In vitro α-glucosidase inhibitory activity revealed the potential efficacy of flavone glycosides, viz., 1, 2, 3, and 4 as antidiabetic agents. In contrast, dihydrochalcone glycosides ( 5- 11) showed weak activity, except for compound 12, which showed relatively strong activity.

AB - Averrhoa carambola L. is reported for its anti-obese and anti-diabetic activities. The present study aimed to investigate its aqueous methanol leaf extract (CLL) in vivo anti-obese activity along with the isolation and identification of bioactive compounds and their in vitro α-glucosidase inhibition assessment. CLL improved all obesity complications and exhibited significant activity in an obese rat model. Fourteen compounds, including four flavone glycosides ( 1- 4) and ten dihydrochalcone glycosides ( 5- 12), were isolated and identified using spectroscopic techniques. New compounds identified in planta included ( 1) apigenin 6- C-(2-deoxy- β-D-galactopyranoside)-7- O- β-D-quinovopyranoside, ( 8) phloretin 3'- C-(2- O-( E)-cinnamoyl-3- O- β-D-fucopyranosyl-4- O-acetyl)- β-D-fucopyranosyl-6'- O- β-D fucopyranosyl-(1/2)-α-L arabinofuranoside, ( 11a) phloretin3'- C-(2- O-( E)-p-coumaroyl-3- O- β-D-fucosyl-4- O-acetyl)- β-D-fucosyl-6'- O-(2- O- β-D-fucosyl)-α-L-arabinofuranoside, ( 11b) phloretin3'- C-(2-O- (Z) -p-coumaroyl-3- O- β-D-fucosyl-4- O-acetyl)- β-D-fucosyl-6'- O-(2- O- β-D-fucosyl)-α-L-arabinofuranoside. Carambolaside M ( 5), carambolaside Ia ( 6), carambolaside J ( 7), carambolaside I ( 9), carambolaside P ( 10a), carambolaside O ( 10b), and carambolaside Q ( 12), which are reported for the first time from A. carambola L. leaves, whereas luteolin 6- C-α-L-rhamnopyranosyl-(1-2)- β-D-fucopyranoside ( 2), apigenin 6- C- β-D-galactopyranoside ( 3), and apigenin 6- C- α-L-rhamnopyranosyl-(1-2)- β-L-fucopyranoside ( 4) are isolated for the first time from Family. Oxalidaceae. In vitro α-glucosidase inhibitory activity revealed the potential efficacy of flavone glycosides, viz., 1, 2, 3, and 4 as antidiabetic agents. In contrast, dihydrochalcone glycosides ( 5- 11) showed weak activity, except for compound 12, which showed relatively strong activity.

UR - http://www.scopus.com/inward/record.url?scp=85136682912&partnerID=8YFLogxK

U2 - 10.3390/molecules27165159

DO - 10.3390/molecules27165159

M3 - Article

C2 - 36014395

VL - 27

JO - Molecules

JF - Molecules

SN - 1420-3049

IS - 16

M1 - 5159

ER -