Maritimetin

Snailase: A Promising Tool for the Enzymatic Hydrolysis of Flavonoid Glycosides From Plant Extracts.[Pubmed:35755698]

Front Plant Sci. 2022 Jun 9;13:889184.

Plants typically contain a broad spectrum of flavonoids in varying concentrations. As a rule, several flavonoid classes occur in parallel, and, even for a single flavonoid, divergent glycosylation patterns are frequently observed, many of which are not commercially available. This can be challenging in studies in which the distribution between flavonoid classes, or features that are not affected by glycosylation patterns, are adressed. In addition, hydrolysis simplifies the quantification process by reducing peak interferences and improving the peak intensity due to the accumulation of the respective aglycone. Effective removal of glycose moieties can also be relevant for technological applications of flavonoid aglycones. Herein, we present a fast and reliable method for the enzymatic hydrolysis glycosides from plant extracts using the commercial enzyme mix snailase, which provided the highest aglycone yields across all investigated flavonoids (aurones: leptosidin, Maritimetin, sulfuretin; chalcones: butein, lanceoletin, okanin, phloretin; dihydroflavonols: dihydrokaempferol; flavanones: eriodictyol, hesperetin; flavones: acacetin, apigenin, diosmetin, luteolin; flavonols: isorhamnetin, kaempferol, myricetin, quercetin; isoflavones: biochanin A, formononetin, genistein) from methanolic extracts of nine plants (Bidens ferulifolia, Coreopsis grandiflora, Fagus sylvatica, Malus x domestica, Mentha x piperita, Petunia x hybrida, Quercus robur, Robinia pseudoacacia, and Trifolium pratense) in comparison to four other enzymes (cellobiase, cellulase, beta-glucosidase, and pectinase), as well as to acidic hydrolysis by hydrochloric acid.

The chemical components of Coreopsis tinctoria Nutt. and their antioxidant, antidiabetic and antibacterial activities.[Pubmed:30499349]

Nat Prod Res. 2020 Jun;34(12):1772-1776.

Seventeen compounds were isolated from the capitula of Coreopsis tinctoria Nutt. with various column chromatographic methods and semi-preparative HPLC. Their structures were identified by the spectroscopic data and comparison with literatures as 2'-hydroxy-4,4'-dimethoxy-chalcone; (1), isoliquiritigenin (2), eriodictyol (3), naringenin (4), Maritimetin (5), butin (6), taxifolin (7), luteolin (8), 7,3',4'-trihydroxyflavone (9), 8,3',4'-trihydroxyflavone-7-O-beta-d-glucoside (10), quercetin (11), quercetagitin-7-O-beta-d-glucoside (12), quercetin-7-O-beta-d-glucoside (13), 3,4-dihydroxybenzoic acid (14), caffeic acid (15), coreoside B (16), and myo-inositol (17). Compounds 1, 4, 9, 10 and 17 were isolated from C. tinctoria Nutt. for the first time. Compounds 7 and 12 possessed the highest antioxidant activity (IC(50) = 64.37 and 32.86 microg/ml, respectively) among the tested compounds (IC(50) value of positive control was 5.34 microg/ml). Compound 7 exhibited potent PTP1B enzymatic inhibition with an IC(50) value of 7.73 mug/ml (IC(50) value of positive control is 1.46 microg/ml). Furthermore, compound 5 showed strong antibacterial activity against the Gram-positive bacterium, S. aureus.

New phenolic compounds from Coreopsis tinctoria Nutt. and their antioxidant and angiotensin i-converting enzyme inhibitory activities.[Pubmed:25516207]

J Agric Food Chem. 2015 Jan 14;63(1):200-7.

Three new phenolic compounds, coretinphenol (1), coretincone (2), and coretinphencone (3), were isolated from the buds of Coreopsis tinctoria Nutt., together with nine known compounds, including butein (4), okanin (5), isoliquiritigenin (6), Maritimetin (7), taxifolin (8), isookanin (9), marein (10), sachalinoside B (11), and 2-phenylethyl-beta-d-glucoside (12). The chemical structures of these compounds were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivity. This work represents the first recorded example of the isolation of compounds 1-3, 6, 7, 9, 11, and 12 from C. tinctoria. Compounds 5-9 showed strong diphenyl(2,4,6-trinitrophenyl)iminoazanium (DPPH) radical-scavenging activity, with IC50 values of 3.35 +/- 0.45, 9.6 +/- 2.32, 4.12 +/- 0.21, 6.2 +/- 0.43, and 7.9 +/- 0.53 muM, respectively. Compounds 2 and 8 exhibited angiotensin I-converting enzyme inhibitory activity, with IC50 values of 228 +/- 4.47 and 145.67 +/- 3.45 muM, respectively. The activities of phenolic compounds isolated from C. tinctoria support the medicinal use of this plant in the prevention of cardiovascular diseases.

[Chemical constituents from Bidens bipinnata].[Pubmed:25282892]

Zhongguo Zhong Yao Za Zhi. 2014 May;39(10):1838-44.

To investigate the chemical constituents of the whole plants of Bidens bipinnata, the separation and purification of constituents were performed by chromatography on macroporous resin, silica gel, MCI and Sephadex LH-20. Their structures were elucidated by spectroscopic data as quercetin (1), quercetin-3-0-alpha-L-rhamnoside (2), keampferol-3-O-beta-D-glucopyranoside (3), keampferol-3-O-alpha-L-rhamnoside (4), 3', 5-dyhydroxy-3, 6, 4'-trimethoxyl -7-O-beta-D-glucopyranoside flavonoid (5), 7, 8, 3', 4'-tetraflavanone(6), (2S)- and (2R)-isookanin-7-O-beta-D- glucopyranoside (7a/7b), (2S)- and (2R)-3'-methoxy-isookanin-8-O-beta-D-glucopyranoside (8a/8b), 6, 7, 3', 4'-tetrahydroxyaurone(9), Maritimetin (10), esculetin (11), 3-O-caffeoyl-2-methyl-d-erythrono-1, 4-lactone (12), (7S, 8R) balanophonin-4-O-beta-D-glucopyranoside (13), eugenyl-O-beta-apiofuranosyl-( 1"-6') -O-beta-glucopyranoside (14), and (+)-syringaresinol-4'-O-beta-D-glucopyranoside (15). Compounds 8, 13, 14, and 15 were isolated from this genus for the first time. Compounds 1 and 6 were potent inhibitors against HSC-T6 cells in vitro and compounds 1, 2, 6, and 7 were capable of decreasing the inflammatory cytokine production of macrophage cells in vitro.

4-Deoxyaurone formation in Bidens ferulifolia (Jacq.) DC.[Pubmed:23667445]

PLoS One. 2013 May 8;8(5):e61766.

The formation of 4-deoxyaurones, which serve as UV nectar guides in Bidens ferulifolia (Jacq.) DC., was established by combination of UV photography, mass spectrometry, and biochemical assays and the key step in aurone formation was studied. The yellow flowering ornamental plant accumulates deoxy type anthochlor pigments (6'-deoxychalcones and the corresponding 4-deoxyaurones) in the basal part of the flower surface whilst the apex contains only yellow carotenoids. For UV sensitive pollinating insects, this appears as a bicoloured floral pattern which can be visualized in situ by specific ammonia staining of the anthochlor pigments. The petal back side, in contrast, shows a faintly UV absorbing centre and UV absorbing rays along the otherwise UV reflecting petal apex. Matrix-free UV laser desorption/ionisation mass spectrometric imaging (LDI-MSI) indicated the presence of 9 anthochlors in the UV absorbing areas. The prevalent pigments were derivatives of okanin and Maritimetin. Enzyme preparations from flowers, leaves, stems and roots of B. ferulifolia and from plants, which do not accumulate aurones e.g. Arabidopsis thaliana, were able to convert chalcones to aurones. Thus, aurone formation could be catalyzed by a widespread enzyme and seems to depend mainly on a specific biochemical background, which favours the formation of aurones at the expense of flavonoids. In contrast to 4-hydroxyaurone formation, hydroxylation and oxidative cyclization to the 4-deoxyaurones does not occur in one single step but is catalyzed by two separate enzymes, chalcone 3-hydroxylase and aurone synthase (catechol oxidase reaction). Aurone formation shows an optimum at pH 7.5 or above, which is another striking contrast to 4-hydroxyaurone formation in Antirrhinum majus L. This is the first example of a plant catechol oxidase type enzyme being involved in the flavonoid pathway and in an anabolic reaction in general.

A DFT study on the radical scavenging activity of maritimetin and related aurones.[Pubmed:18983134]

J Phys Chem A. 2008 Nov 27;112(47):12196-202.

The radical scavenging activity of Maritimetin and a series of synthetic aurones has been studied by using density functional theory with the B3LYP exchange correlation functional. The computation of various molecular descriptors that could assist the elucidation of hydrogen atom and electron donating ability of the selected compounds was carried out in the gas phase and in the liquid phase (benzene, methanol, water) with the aid of IEF-PCM. For reasons of comparison a series of simple phenols of known activity were also included in the study. The results are discussed with regards to the structure-activity relationship principles of flavonoids and in particular to the capacity of the selected aurones to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH(*)) and superoxide anion (O(2)(-*)) radicals. The O-H bond dissociation enthalpy (BDE) seems to be the most proper parameter to characterize the antiradical properties of the studied compounds. The hydroxylation pattern in ring B defines the order of activity, while the extended conjugation and especially the presence of a catechol moiety in ring A are responsible for the high activity observed experimentally for the selected aurones.