Anti‐inflammatory effects of chemical components from Ginkgo biloba L. male flowers on lipopolysaccharide‐stimulated RAW264.7 macrophages

Abstract

Ginkgo biloba L., well known as living fossil, have various pharmacological activities. Eighteen compounds were isolated from Ginkgo male flowers including a novel matsutake alcohol glycoside, Ginkgoside A (1), and 17 known compounds—calaliukiuenoside (2), benzylalcohol O‐α‐l‐arabinopyranosyl‐(1 → 6)‐β‐d‐glucopyranoside (3), amentoflavone (4), sciadopitysin (5), bilobetin (6), isoginkgetin (7), olivil 4‐O‐β‐d‐glucopyranoside (8), dihydrodehydrodiconiferyl alcohol‐4‐O‐β‐d‐glucoside (9), (+)‐cyclo‐olivil‐6‐O‐β‐d‐glucopyranoside (10), (−)‐isolariciresinol 4‐O‐β‐d‐glucopyranoside (11), coniferin (12), trans‐cinnamic acid‐4‐O‐β‐d‐glucopyranoside (13), p‐coumaryl alchol glucoside (14), stroside B (15), methylconiferin (16), cis‐p‐coumaric acid 4‐O‐β‐d‐glucopyranoside (17), and cis‐coniferin (18). Thirteen of these compounds had not previously found in Ginkgo. All extractive fractions and isolated compounds were evaluated for their anti‐inflammatory ability in the lipopolysaccharide‐induced RAW264.7 macrophages. The ethanol extract of Ginkgo flowers and the chloroform and ethyl acetate fractions can significantly decrease nitric oxide (NO), interleukin‐6 (IL‐6), and prostaglandin E2 (PGE2) production at 100 μg/ml. The most effective compounds, bilobetin (6) and isoginkgetin (7), elevated the NO inhibition ratios to 80.19% and 82.37% at 50 μM, respectively. They also exhibited significant dose‐dependent inhibitory effects on tumor necrosis factor‐α, IL‐6, PGE2, inducible NO synthase mRNA, and cyclooxygenase‐2 mRNA levels. So they can be promising candidates for the development of new anti‐inflammatory agents.

Anticancer Effects of Five Biflavonoids from Ginkgo Biloba L. Male Flowers In Vitro

“…Since in our present study, compounds 3 and 4 with methoxyl groups at 4′ or/and 4′′′ in the B rings exhibited better anti-proliferative activities. So, the methoxyl group at 4′ and 4′′′ in the B rings of amentoflavone-type biflavonoids may be significant for their anti-proliferative activities, which are consistent with their better anti-inflammatory activities [20].…”

“…The identification of the four known biflavonoids, including amentoflavone ( 2 ) [22], bilobetin ( 3 ), isoginkgetin ( 4 ) [21], sciadopitysin ( 5 ) [23], were reported in our previous studies [20].…”

“…Anti-inflammatory therapy is efficacious for tumor prevention and suppression to some degree [26]. In our previous study, we evaluated the anti-inflammatory activities of the four known biflavonoids and found that bilobetin ( 3 ) and isoginkgetin ( 4 ) showed promising anti-inflammatory activities [20]. Bilobetin ( 3 ), one of biflavonoids, possesses a variety of biological activities [27,28,29].…”

“…So far, there is little correlative literature illustrating the exact chemical constituents and bioactivities of the flowers. In our previous study, we isolated 18 compounds including 4 biflavonoids from Ginkgo male flowers and reported their anti-inflammatory activities in LPS-induced RAW 264.7 cells [20]. In our continuing efforts to investigate the constituents and bioactivities of G. biloba flowers, a novel biflavonoid as well as four known ones were isolated and evaluated for anti-proliferation activities on three kinds of cancer cells for the first time.…”

Identification of bilobetin metabolites, in vivo and in vitro, based on an efficient ultra‐high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry strategy

“…Bilobetin is a biflavonoid extracted from G. biloba. It has antioxidation [2], anticancer, antibacterial [3], antifungal [4], anti-inflammatory [5], antiviral [6], free-radicals scavenging, osteoblast differentiation promoting [7], and other biological activities. It has the potential to treat diseases such as cancer, infectious diseases, fungal melasma, herpes, and osteoporosis.…”