α-Glucosidase and α-amylase inhibitory potential of main compounds and drug candidates from Elaeagnus rhamnoides (L.) A. Nelson

Phytochemistry and pharmacology of sea buckthorn (Elaeagnus rhamnoides; syn. Hippophae rhamnoides): progress from 2010 to 2021

“…Simple flavonol glycosides of SB leaves are generally similar to those from the fruit and seeds. Several such compounds were purified between 2010–2021, including 3- O -β-glucosides, 3- O -rutinosides, and 3- O -β-glucoside-7- O -α-rhamnosides of isorhamnetin, kaempferol and quercetin, as well as 7- O -α-rhamnosides of isorhamnetin and quercetin (Kim et al 2011 ; Yang et al 2013 ; Yuca et al 2022 ). Unlike the fruit and seeds, leaves of E. rhamnoides were reported to contain tiliroside (kaempferol 3- O -(6- O - E - p -coumaroyl)-β-D-glucoside), which was quite frequently isolated (Kim et al 2011 ; Yang et al 2013 ; Yuca et al 2022 ), or detected by LC–MS (Ma et al 2019 ; Skalski et al 2020 ).…”

“…Several such compounds were purified between 2010–2021, including 3- O -β-glucosides, 3- O -rutinosides, and 3- O -β-glucoside-7- O -α-rhamnosides of isorhamnetin, kaempferol and quercetin, as well as 7- O -α-rhamnosides of isorhamnetin and quercetin (Kim et al 2011 ; Yang et al 2013 ; Yuca et al 2022 ). Unlike the fruit and seeds, leaves of E. rhamnoides were reported to contain tiliroside (kaempferol 3- O -(6- O - E - p -coumaroyl)-β-D-glucoside), which was quite frequently isolated (Kim et al 2011 ; Yang et al 2013 ; Yuca et al 2022 ), or detected by LC–MS (Ma et al 2019 ; Skalski et al 2020 ). Similarly to SB seeds, the leaves contain also flavonol glycosides acylated with menthiafolic acid: 12 , kaempferol 3- O -β-D-glucoside-7- O -{3- O -[2( E )-2,6-dimethyl-6-hydroxy-2,7-octadienoyl]}-α-L-rhamnoside ( 13 ), and isorhamnetin 3- O -β-D-glucoside-7- O -{2- O -[2( E )-2,6-dimethyl-6-hydroxy-2,7-octadienoyl]}-α-L-rhamnoside ( 17 ) (Yang et al 2013 ).…”

“…sinensis : hippophoside A (3- O -[β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosyl-13-ene-19-one-28-oic acid 28- O -β-D-glucopyranosyl ester) ( 87 ), hippophoside B (3- O -[β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosyl-13-ene-19-one-30-hydroxyolean-28-oic acid 28- O -β-D-glucopyranosyl ester) ( 88 ), hippophoside C (3- O -[β-D-glucopyranosyl(1 → 2)-β-D-glucopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-glucopyranosyl-13-ene-19-one-28-oic acid 28- O -β-D-glucopyranosyl ester) ( 89 ), hippophoside D (3- O -[β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-glucopyranosyl-13-ene-19-one-30-hydroxyolean-28-oic acid 28- O -β-D-glucopyranosyl ester) ( 90 ) (Chen et al 2014a ), hippophoside E (1- O -[(3β)-3-{[β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 3)-β-D-glucopyranosyl]oxy}-19,28-dioxoolean-13(18)-en-28-yl]-β-D-glucopyranose) ( 9 1), and hippophoside F (1- O -[(3β)-3-{[6-deoxy-α-L-mannopyranosyl-(1 → 2)-[β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 3)]-α-L-arabinopyranosyl]oxy}-19,28-dioxoolean-13(18)-en-28-yl]-β-D-glucopyranose) ( 92 ) (Gao et al 2015 ). Another compound, arjunglucoside I ( 93 ) has been recently isolated from SB leaves (Yuca et al 2022 ). Moreover, 19 triterpenoid glycosides (different from those mentioned above), derivatives of C 30 H 48 O 3 , C 30 H 48 O 4 and C 30 H 48 O 5 , were tentatively identified by LC-HRMS in a fraction of SB leaf extract (Skalski et al 2018 ; Żuchowski et al 2020 ); several compounds showing similar m/z values (however, reported without any identification and MS2 fragments) were also detected by LC-HRMS in extracts from SB fruit and leaves by Zheng et al ( 2019 ).…”

“…IC 50 values for DPPH · scavengers were 522 µM for isorhamnetin 3- O -glucoside-7- O -rhamnoside, 161 µM for isorhamnetin-7- O -rhamnoside, 91 µM for quercetin 3- O -glucoside, 395 µM for isorhamnetin 3- O -rutinoside, 777 µM for isorhamnetin 3- O -glucoside, and 14 µM for casuarinin. In the case of ABTS · scavenging activity, the respective IC 50 were 18, 27, 11, 14, 16, and 2 µM, as well as 558 µM for arjunglucoside I ( 93 ) (Yuca et al 2022 ). Arimboor and Arumughan ( 2012 ) investigated several aspects of antioxidant properties of SB leaf extracts, quercetin, kaempferol, isorhamnetin, rutin, and gallic acid.…”

“…The highest inhibitory effect was observed (at 5 µg mL −1 ) for the butanol fraction of the crude leaf extract (Kim et al 2011 ). α-Glucosidase inhibitors from SB leaves include also the ellagitannin casuarinin (IC 50 21 µM) and the saponin arjunglucoside I (IC 50 1074 µM; 93) (Yuca et al 2022 ). Moreover, five acylated derivatives of kaempferol 3- O -soporoside-7- O -rhamnoside (1, 2, 4, 9, 10) from seeds of H. rhamnoides ssp .…”