Coumaroyl and feruloyl flavonoid glycosides from the male flowers of Ginkgo biloba L. and their inhibitory activity against α-glucosidase

Ginkgo (Ginkgo biloba L.) is a high-value medicinal tree species characterized by its flavonoids beneficial effects that are abundant in leaves. We performed a temporospatial comprehensive transcriptome and metabolome dynamics analyses of clonally propagated Ginkgo plants at four developmental stages (time: May to August) across three different environments (space) to unravel leaves flavonoids biosynthesis variation. Principal component analysis revealed clear gene expression separation across samples from different environments and leaf-developmental stages. We found that flavonoid-related metabolism was more active in the early stage of leaf development, and the content of total flavonoid glycosides and the expression of some genes in flavonoid biosynthesis pathway peaked in May. We also constructed a co-expression regulation network and identified eight GbMYBs and combining with other TF genes (3 GbERFs, 1 GbbHLH, and 1 GbTrihelix) positively regulated the expression of multiple structural genes in the flavonoid biosynthesis pathway. We found that part of these GbTFs (Gb_11316, Gb_32143, and Gb_00128) expressions was negatively correlated with mean minimum temperature and mean relative humidity, while positively correlated with sunshine duration. This study increased our understanding of the molecular mechanisms of flavonoids biosynthesis in Ginkgo leaves and provided insight into the proper production and management of Ginkgo commercial plantations.

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Angiotensin I-converting Enzyme (ACE) Inhibitory Activity and Chemical Composition of Alchemilla Viridiflora Rothm.

10.21203/rs.3.rs-920698/v1 ◽

2021 ◽

Author(s):

Jelena Radović ◽

Relja Suručić ◽

Marjan Niketić ◽

Tatjana Kundakovic-Vasovic

Keyword(s):

Inhibitory Activity ◽

Methanol Extract ◽

Flavonoid Glycosides ◽

Herbaceous Plant ◽

Converting Enzyme ◽

Angiotensin I ◽

Ace Inhibitory Activity ◽

Angiotensin I Converting Enzyme ◽

Ace Inhibitory

Abstract Alchemilla viridiflora Rothm., Rosaceae is a herbaceous plant widespread in central Greece, Bulgaria, North Macedonia and Serbia with Kosovo. LC-MS analysis leads to the identification of 20 compounds in methanol extract, mainly ellagitannins and flavonoid glycosides. Considering that different plant extracts were traditionally used for treatment of hypertension and that some of the analyzed methanol extract constituents possess beneficial cardiovascular effects, we hypothesized that some of these effects are achieved through inhibition of angiotensin I-converting enzyme (ACE). The dose-dependent activities ACE inhibitory activity of A. viridiflora and miquelianin were observed with an IC50 of 2.51 ± 0.00 µg/ml of A. viridiflora compared to IC50 of 2.59 ± 0.00 µg/mL for miquelianin. Contribution of the single compounds to the tested activity was further analyzed through the in silico experimental approach. Computational docking results showed that tiliroside, ellagic acid pentose and galloyl-HHDP-glucose exhibited even better binding affinity for ACE active site than miquelianin, which ACE activity was confirmed by an in vitro assay.

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

Molecules ◽

10.3390/molecules24081496 ◽

2019 ◽

Vol 24 (8) ◽

pp. 1496 ◽

Cited By ~ 7

Author(s):

Li ◽

Xia ◽

Tian ◽

Zhang ◽

...

Keyword(s):

Anticancer Agents ◽

Hela Cells ◽

Ginkgo Biloba ◽

Morphological Changes ◽

Dependent Manner ◽

Anticancer Effects ◽

Proapoptotic Protein ◽

M Phase ◽

Male Flowers

Ginkgo biloba L., an ancient dioecious gymnosperm, is now cultivated worldwide for landscaping and medical purposes. A novel biflavonoid—amentoflavone 7''-O-β-D-glucopyranoside (1)—and four known biflavonoids were isolated and identified from the male flowers of Ginkgo. The anti-proliferative activities of five biflavonoids were evaluated on different cancer lines. Bilobetin (3) and isoginkgetin (4) exhibited better anti-proliferative activities on different cancer lines. Their effects were found to be cell-specific and in a dose and time dependent manner for the most sensitive HeLa cells. The significant morphological changes validated their anticancer effects in a dose-dependent manner. They were capable of arresting the G2/M phase of the cell cycle, inducing the apoptosis of HeLa cells dose-dependently and activating the proapoptotic protein Bax and the executor caspase-3. Bilobetin (3) could also inhibit the antiapoptotic protein Bcl-2. These might be the mechanism underlying their anti-proliferation. In short, bilobetin (3) and isoginkgetin (4) might be the early lead compounds for new anticancer agents.

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Antiapoptotic Effects of EGb 761

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/495703 ◽

2013 ◽

Vol 2013 ◽

pp. 1-18 ◽

Cited By ~ 11

Author(s):

Norma Serrano-García ◽

José Pedraza-Chaverri ◽

José Juan Mares-Sámano ◽

Marisol Orozco-Ibarra ◽

Arturo Cruz-Salgado ◽

...

Keyword(s):

Ginkgo Biloba ◽

Membrane Integrity ◽

Flavonoid Glycosides ◽

Defense Enzymes ◽

Egb 761 ◽

Cytochrome C Release ◽

Cellular Defense ◽

Apoptosis Process ◽

Protein Transcription ◽

Active Substances

Ginkgo bilobaextracts have long been used in Chinese traditional medicine for hundreds of years. The most significant extract obtained fromGinkgo bilobaleaves has been EGb 761, a widely used phytopharmaceutical product in Europe. EGb 761 is a well-defined mixture of active compounds, which contains two main active substances: flavonoid glycosides (24–26%) and terpene lactones (6–8%). These compounds have shown antiapoptotic effects through the protection of mitochondrial membrane integrity, inhibition of mitochondrial cytochrome c release, enhancement of antiapoptotic protein transcription, and reduction of caspase transcription and DNA fragmentation. Other effects include the reduction of oxidative stress (which has been related to the occurrence of vascular, degenerative, and proliferative diseases), coupled to strong induction of phase II-detoxifying and cellular defense enzymes by Nrf2/ARE activation, in addition to the modulation of transcription factors, such as CREB, HIF-1α, NF-κB, AP-1, and p53, involved in the apoptosis process. This work reviews experimental results about the antiapoptotic effects induced by the standardized extract ofGinkgo bilobaleaves (EGb 761).

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