Showing papers on "Flavanone published in 2008"
TL;DR: There was a small but significant decrease in the excretion of hesperetin (but not naringenin) with increasing age, but the effects of sex, BMI and contraceptive pill use were shown not to be associated with the variation in flavanone excretion.
Abstract: Oranges are rich sources of flavonoids that are bioactive and may protect against age-related diseases. The absorption of orange flavanones may be affected by factors such as processing and subject anthropometric variables, and the bioactivity of the absorbed phytochemicals depends on how they are metabolised during absorption. In a randomised cross-over study, twenty subjects consumed a single portion of orange fruit (150 g) or juice (300 g) that contained the flavanones narirutin and hesperidin, and an additional 109 subjects across a broad age range (18-80 years) consumed the juice. Flavanone metabolites were measured in regularly collected samples of plasma and urine. After consumption of fruit or juice, flavanone conjugates, but not the aglycones, were detected in plasma and urine. The flavanone conjugates were shown to include the 7- and 4'-O-monoglucuronides of naringenin, the 7- and 3'-O-monoglucuronides of hesperetin, two hesperetin diglucuronides and a hesperetin sulfo-glucuronide, but no aglycones or rutinosides. Analysis of the plasma pharmacokinetic and urinary excretion data on a dose-adjusted basis indicated no difference in absorption or excretion of either flavanone between the fruit and juice matrices. In the extended urinary excretion dataset the individual variation was very large (range 0-59 % urinary yield). There was a small but significant (P < 0.05) decrease in the excretion of hesperetin (but not naringenin) with increasing age (P < 0.05), but the effects of sex, BMI and contraceptive pill use were shown not to be associated with the variation in flavanone excretion.
129 citations
TL;DR: This work studied the inhibition of three flavonoids against the β‐hydroxyacyl‐acyl carrier protein dehydratase from Helicobacter pylori, finding the methoxy group at C‐7 of (S)‐sakuranetin seems to play an important role for the inhibitor's binding to HpFabZ.
Abstract: Flavonoids, with the largest and most important group of polyphenolic compounds in plants, are major functional components of many herbal and insect preparations for medical use (Havsteen 2002; Cushnie and Lamb 2005). For decades of medical research, flavonoids have been reported to possess varied pharmacological and biochemical properties, including anti-inflammatory, antioxidant, antiallergic, antimicrobial, antitumor, antiplatelet, and estrogenic activities, as well as the inhibition of various enzymes, such as hydrolases, oxidoreductases, DNA synthetases, RNA polymerases, phosphatases, protein phosphokinases, oxygenases, and amino acid oxidases (Harborne and Williams 2000; Havsteen 2002; Ross and Kasum 2002; Cushnie and Lamb 2005).
Quercetin (3,3′,4′,5,7-pentahydroxyflavone), apigenin (4′,5,7-trihydroxyflavone), and sakuranetin (5,4′-dihydroxy-7-methoxyflavanone) are three representative flavonoids. Quercetin belongs to the flavonol class, which exists in foods such as citrus fruit, buckwheat, and onions. It has been demonstrated that quercetin has significant anti-inflammatory activity, antitumor activity, antioxidant activity, and vitamin C-sparing action and has been recognized as the most active flavonoid in study. Apigenin belongs to the flavone class and is isolated from parsley and celery. It has antioxidant, anti-inflammatory, and antitumor properties just like most of the other flavonoids. Sakuranetin falls into the flavanone class and is isolated from many plants (Hurabielle et al. 1982; Liu et al. 1992; Abdel-Sattar et al. 2000). It was discovered to possess anti-inflammatory activity and proved to be a phytoalexin (Nakazato et al. 2000; Hernandez et al. 2007). In addition, all these three flavonoids were reported to exhibit antibacterial activity, probably by acting on multiple cellular targets (Konstantinopoulou et al. 2003; Cushnie and Lamb 2005), such as DNA gyrase (Ohemeng et al. 1993) and cytoplasmic membrane (Mirzoeva et al. 1997). Recently, quercetin and apigenin were found to inhibit some enzymes involved in the type II fatty acid biosynthesis (FAS II) pathway. In detail, quercetin could inhibit β-ketoacyl-acyl carrier protein reductase (FabG) and enoyl–acyl carrier protein reductase (FabI) of Plasmodium falciparum as well as β-hydroxyacyl–acyl carrier protein dehydratase (FabZ) from P. falciparum and Helicobacter pylori, while apigenin could only inhibit FabI from P. falciparum and FabZ from H. pylori (Tasdemir et al. 2006; Zhang et al. 2008).
In this work, the flavonoid (S)-sakuranetin was identified as a new HpFabZ inhibitor. More importantly, to characterize the inhibitory mechanism of HpFabZ by quercetin, apigenin, and (S)-sakuranetin, complex crystal structure analyses with kinetically enzymatic assays were carried out. These flavonoids were found to be competitive inhibitors against HpFabZ by binding to the substrate tunnel and preventing the substrate from accessing the active site. Considering the fact that the reports on the antibacterial activity of flavonoids often show wide discrepancies from each other (Cushnie and Lamb 2005), the anti-H. pylori activities of these three inhibitors were also tested by the standard agar dilution method. Our work is expected to provide useful information for understanding the potential antibacterial mechanism of flavonoids.
128 citations
107 citations
TL;DR: Bioassay-guided fractionation of the methanolic extracts of the pulp and seeds of the fruits of Syzygium samarangense Merr.
106 citations
TL;DR: Flavonoids were able to down-regulate LPS-induced tumour necrosis factor production and flavonoids with a 4'-OH substitution in the B-ring are more potent than those with a 3'-OH-4'-methoxy substitution, and flav onoids of the flavone type (with a C2=C3 double bond) are more powerful than those of the flavourside type ( with a at C2-C3 single bond).
Abstract: Lipopolysaccharides released during bacterial infections induce the expression of proinflammatory cytokines and lead to complications such as neuronal damage in the CNS and septic shock in the periphery. While the initial infection is treated by antibiotics, anti-inflammatory agents would be advantageous add-on medications. In order to identify such compounds, we have compared 29 commercially available polyphenol-containing plant extracts and pure compounds for their ability to prevent LPS-induced up-regulation of NO production. Among the botanical extracts, bearberry and grape seed were the most active preparations, exhibiting IC values of around 20 μg/mL. Among the pure compounds, IC values for apigenin, diosmetin and silybin were 15, 19 and 12 μM, in N-11 murine microglia, and 7, 16 and 25 μM, in RAW 264.7 murine macrophages, respectively. In addition, these flavonoids were also able to down-regulate LPS-induced tumour necrosis factor production. Structure-activity relationships of the flavonoids demonstrated three distinct principles: (i) flavonoidaglycons are more potent than the corresponding glycosides, (ii) flavonoids with a 4′-OH substitution in the B-ring are more potent than those with a 3′-OH-4′-methoxy substitution, (iii) flavonoids of the flavone type (with a C2=C3 double bond) are more potent than those of the flavanone type (with a at C2-C3 single bond).
81 citations
TL;DR: The biochemical properties of the Arabidopsis thaliana F3H enzyme are described and the activities of gene products from four other plant species previously identified as having high homology to AtF3H are confirmed, indicating that the absence of F2H in these lines enables the synthesis of uncommon 3-deoxy flavonoids in theArabidopsis seed coat.
80 citations
TL;DR: The strong correlation between the concentration of catechins and CsF3H expression indicates a critical role of F3H in catechin biosynthesis.
Abstract: Tea (Camellia sinensis (L.) O. Kuntze) leaves are a major source of flavonoids that mainly belong to the flavan 3-ols or catechins. Apart from being responsible for tea quality, these compounds have medicinal properties. Flavanone 3-hydroxylase (F3H) is an abundant enzyme in tea leaves that catalyzes the stereospecific hydroxylation of (2S)-naringenin to form (2R,3R)-dihydrokaempferol. We report a full-length cDNA sequence of F3H from tea (CsF3H Accession no. AY641730). CsF3H comprised 1365 bp with an open reading frame of 1107 nt (from 43 to 1149) encoding a polypeptide of 368 amino acids. Expression of CsF3H in an expression vector in Escherichia coli yielded a functional protein with a specific activity of 32 nmol min(-1) mg protein(-1). There was a positive correlation between the concentration of catechins and CsF3H expression in leaves of different developmental stages. CsF3H expression was down-regulated in response to drought, abscisic acid and gibberellic acid treatment, but up-regulated in response to wounding. The concentration of catechins paralleled the expression data. Exposure of tea shoots to 50-100 microM catechins led to down-regulation of CsF3H expression suggesting substrate mediated feedback regulation of the gene. The strong correlation between the concentration of catechins and CsF3H expression indicates a critical role of F3H in catechin biosynthesis.
76 citations
TL;DR: Quantitative analysis data obtained thus far have shown that Crocus sativus petals are a rich source of flavonoids, which suggests that the good antioxidant capacity detected in the various fractions of Crocus sitiva petals could be attributed to the presence of flav onoids.
Abstract: In this study, various fractions isolated from the petals of Crocus sativus were assessed at first for their phenolic content both qualitatively and quantitatively and secondly for their antioxidant activity. The phytochemical analysis was carried out by LC-DAD-MS (ESI (+)) whereas the antioxidant potential was evaluated by applying two methodologies, the DPPH. radical scavenging activity test and the Co(II)-induced luminol chemiluminescence procedure. According to data obtained from these antioxidant tests, the diethyl ether, ethyl acetate and aqueous fractions demonstrated the strongest antioxidant capacity. Interestingly, the major constituents identified in these fractions correspond to kaempferol, quercetin, naringenin and some flavanone and flavanol derivatives glycosylated and esterified with phenylpropanoic acids. In addition, the presence of some nitrogen-containing substances, as well as other phenolics and phenylpropanoic derivatives was also traced. The identification and structural elucidation of all substances isolated in this study was achieved by both comparing available literature data and by proposed fragmentation mechanisms based on evaluating the LC-DAD-MS (ESI (+)) experimental data. The quantitative analysis data obtained thus far have shown that Crocus sativus petals are a rich source of flavonoids. Such a fact suggests that the good antioxidant capacity detected in the various fractions of Crocus sativus petals could be attributed to the presence of flavonoids, since it is already known that these molecules exert antioxidant capability. The latter, along with the use of Crocus sativus in food and pharmaceutical industry is discussed.
70 citations
TL;DR: A novel 2,3-dioxygenated flavanone, erigeroflavanone, as well as eight known flavonoids and two known gamma-pyranone derivatives, were isolated from an ethyl acetate-soluble extract of the flowers of Erigeron annuus and the structure of compound 1 was elucidated by interpretation of spectroscopic data.
Abstract: A novel 2,3-dioxygenated flavanone, erigeroflavanone (1), as well as eight known flavonoids and two known γ-pyranone derivatives, were isolated from an ethyl acetate-soluble extract of the flowers of Erigeron annuus. The structure of compound 1 was elucidated by interpretation of spectroscopic data. All of the isolates were subjected to in vitro bioassays to evaluate their inhibitory activity against advanced glycation end products formation and rat lens aldose reductase.
66 citations
TL;DR: Ethyl acetate extract from the stem bark of Erythrina fusca showed a antimalarial activity against the multi-drug-resistant strain (K1) of Plasmodium falciparum, and six flavonoids, lupinifolin, citflavanone, erythrisenegalone, lonchocarpol A, and 8-prenyldaidzein were isolated from the extract.
Abstract: Ethyl acetate (EtOAc) extract from the stem bark of Erythrina fusca showed a antimalarial activity against the multi-drug-resistant strain (K1) of Plasmodium falciparum, and six flavonoids, lupinifolin (1), citflavanone (2), erythrisenegalone (3), lonchocarpol A (4), liquiritigenin (5), and 8-prenyldaidzein (6), were isolated from the extract. Diprenylated flavanone 4 showed a notable antimalarial activity (IC50; 1.6 μg/mL); however 1 and 3 did not show the activity, even though these compounds possessed prenylated substitution.
64 citations
TL;DR: Chemical investigation of the methanol extract of the viscous secretion on the surface of immature fruits of Paulownia tomentosa furnished nine geranylated flavanones, including 6-geranyl-5,7-dihydroxy-3',4'-dimethoxyflavanone, which showed potent radical scavenging effects towards DPPH radicals.
TL;DR: Four UDP-dependent glucosyltransferase genes were cloned from rice, expressed in Escherichia coli, and purified to homogeneity to find out whether these enzymes could use flavonoids as glucose acceptors, apigenin, daidzein, genistein, kaempferol, luteolin, naringenin, and quercetin were used as potential glucose acceptor.
TL;DR: Methanolic extracts of trunk exudates of Dalbergia sissoo yielded two new open-chain neoflavonoids (1, 2), a new flavonoid (3), anew flavanone (4), and 26 known compounds that exhibited significant activity in a concentration-dependent manner.
Abstract: Methanolic extracts of trunk exudates of Dalbergia sissoo yielded two new open-chain neoflavonoids (1, 2), a new flavonoid (3), a new flavanone (4), and 26 known compounds. Their structures were elucidated by detailed spectroscopic analyses. The ability of the isolated compounds to prevent nitric oxide (NO) production by LPS-stimulated J774.1 cells was also studied. All of the isolated compounds except 4, formononetin, and zenognosin B exhibited significant activity in a concentration-dependent manner. Compounds 2 and 3 were among the most potent NO production inhibitors, with IC50 values of 3.19 and 6.22 microM, respectively, and compound 1 had an IC50 of 31.6 microM.
TL;DR: Lavandulyl flavanones reduced Abeta secretion dose-dependently in transfected human embryonic kidney (HEK-293) cells and in kinetic studies, all compounds screened were shown to be noncompetitive inhibitor.
TL;DR: It is suggested that 6PP impairs the hepatic energy metabolism by acting as mitochondrial uncoupler and by inhibiting enzymatic activities linked to the respiratory chain.
Journal Article•
TL;DR: The flavanone 3-beta-hydroxylase (GmF3H) gene was cloned from soybean and shown to convert eriodictyol and naringenin into taxifolin and dihydrokaempferol, respectively and appear to be key enzymes in the biosynthesis of the UV-protectant, ka Kempferol.
Abstract: There are several branch points in the flavonoid synthesis pathway starting from chalcone. Among them, the hydroxylation of flavanone is a key step leading to flavonol and anthocyanin. The flavanone 3-beta-hydroxylase (GmF3H) gene was cloned from soybean (Glycine max cultivar Sinpaldal) and shown to convert eriodictyol and naringenin into taxifolin and dihydrokaempferol, respectively. The major flavonoids in this soybean cultivar were found by LC-MS/MS to be kamepferol O-triglycosides and O-diglycosides. Expression of GmF3H and flavonol synthase (GmFLS) was induced by ultraviolet-B (UV-B) irradiation and their expression stimulated accumulation of kaempferol glycones. Thus, GmF3H and GmFLS appear to be key enzymes in the biosynthesis of the UV-protectant, kaempferol.
TL;DR: OsFNS I-1 encodes a flavone synthase I, the first type I FNS I found outside of the Apiaceae family, and it is found that the cofactors oxoglutarate, FeSO(4), ascorbate and catalase are required for this reaction.
Abstract: Flavones are synthesized from flavanones through the action of flavone synthases (FNSs). There are two FNSs, FNS I and II. FNS I is a soluble dioxygenase present in members of the Apiaceae family and FNS II is a membrane bound cytochrome P450 enzyme that has been identified in numerous plant species. In this study, we cloned OsFNS I-1 from rice by RTPCR, expressed it in E. coli, and purified the recombinant protein. By NMR analysis, we found that OsFNS I-1 converted the flavanone (2S)-naringenin into the flavone, apigenin. Moreover, we found that the cofactors oxoglutarate, FeSO(4), ascorbate and catalase are required for this reaction. OsFNS I-1 encodes a flavone synthase I. This is the first type I FNS I found outside of the Apiaceae family.
TL;DR: The major flavonoids in rice leaves were analyzed via LC-MS/MS after their total flavonoid extracts were hydrolyzed and cloned and characterized OsFNS, which catalyzes the reaction from flavanone (naringenin) to flavone (apigenin).
Abstract: The major flavonoids in rice leaves were analyzed via LC-MS/MS after their total flavonoid extracts were hydrolyzed. The most abundant flavones were apigenin, luteolin, and tricetin. Of these, tricetin was methylated at its 3′ and 5′-hydroxyl group to form tricin, which was probablyO-glycosylated. Both 3′-O-methylated luteolin and luteolin were found in theC-glycosylated form while apigenin wasC-glycosylated. We also cloned and characterizedOsFNS, which catalyzes the reaction from flavanone (naringenin) to flavone (apigenin). Analysis of the reaction product with recombinant OsFNS showed that it indeed converts naringenin to apigenin.
TL;DR: This micellar electrokinetic capillary chromatography method could simultaneously quantify the 10 flavonoids and be used in the quality control of functional foods containing propolis and Ginkgo biloba.
Abstract: A micellar electrokinetic capillary chromatography (MEKC) method has been developed for simultaneous determination of 10 bioactive flavonoids: rutin, apigenin, luteolin, eriodictyol, kaempferol, chrysin, acacetin, flavanone, flavone, and fisetin. The effect of several parameters, such as UV detection wavelength, buffer pH, buffer concentration, sodium dodecyl sulfate (SDS) concentration, β-cyclodextrin (β-CD) concentration, separation voltage, and injection time on the separation of these flavonoids were systematically investigated. The 10 flavonoids were successfully separated within 18 min in 20 mM Na2B4O7−10 mM NaH2PO4 buffer (pH 9.7) containing 100 mM SDS and 16 mM β-CD at a separation voltage of 19 kV, with UV detection at 254 nm. Regression analysis revealed a good linear relationship between the peak area of each analyte and its concentration with detection limits (S/N = 3), ranging from 0.15 to 1.36 μg mL−1. This method could simultaneously quantify the 10 flavonoids and be used in the quality con...
TL;DR: A pair of flavanone glucoside diastereomers, (2R)- and (2S)-eriodictyol-5-O-beta-d-glucopyranoside (1a, 1b), was successfully separated by RP-C(18) high-performance liquid chromatography from Balanophora involucrata Hook.
TL;DR: It was shown that the 2'-OH group would make the C-ring of flavonoids studied more labile through a six-membered mechanism, resulting in base peaks of (1,3)A+ (positive mode) and ( 1,4)A(-) (negative mode).
Abstract: Eighteen isoprenylated flavonoids (8 flavanones, 3 flavanols, and 7 chalcones) isolated from Kushen or synthesized were studied by positive and negative ion electrospray ionization multistage tandem mass spectrometry (ESI-MS(n)). Plausible fragmentation patterns were obtained by comparing their MS(n) spectra with each other, which were further supported by high-resolution MS data and two model compounds. It was shown that the 2'-OH group would make the C-ring of flavonoids studied more labile through a six-membered mechanism, resulting in base peaks of (1,3)A+ (positive mode) and (1,4)A(-) (negative mode). In addition, the 2'-OH is also responsible for the neutral loss of water in (+)ESI/MS(2) of flavanones. The neutral loss of water (or methanol) in (-)ESI/MS(2) of flavanols was elucidated by a E2 elimination mechanism. Different relative abundances (RA) of (1,3)A(+) and S(+) in (+)ESI/MS(2) spectra were used to discriminate flavanones with their open-ring products, chalcones, since the equilibrium for flavanone chalcone isomerization in ESI ion source could not be obtained in positive mode.
TL;DR: This report reports the profiling of chalcones and flavanones in fruits of the dwarf tomato cultivar Micro-Tom using liquid chromatography Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICR-MS), and demonstrates the first report that demonstrates the presence of eriodictyol chalcone and eriodictsyol in tomato.
Abstract: Tomato (Solanum lycopersicum) is one of a group of plants that accumulate chalcones and flavanones. However, the molecular diversity of chalcones, flavanones, and their conjugate metabolites has not been investigated intensively. Here, we report the profiling of chalcones and flavanones in fruits of the dwarf tomato cultivar Micro-Tom using liquid chromatography Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICR-MS). We identified eriodictyol chalcone and eriodictyol aglycones, along with naringenin chalcone and naringenin aglycones. To our knowledge, this is the first report that demonstrates the presence of eriodictyol chalcone and eriodictyol in tomato. We detected 26 conjugate metabolites of chalcones and flavanones. Chemical information obtained simultaneously by LC-FTICR-MS, including m/z values, MS/MS spectra, UV absorption spectra, and retention times, facilitated the elucidation of molecular formulas and conjugate structures of the metabolites. Eriodictyol chalcone and eriodictyol conjugates had the same modification patterns seen in naringenin chalcone and naringenin conjugates. Chalcones and flavanones were much more abundant in tomato fruit peel than flesh. Accumulation profiles during ripening were classified into three groups. The first group included metabolites that showed the highest accumulation levels at the breaker stage, and then decreased during ripening. The second group included metabolites that accumulated to the highest levels at the turning stage, and then decreased at the red stage. The third group included metabolites that accumulated gradually during ripening, and showed the highest accumulation levels at the red stage. These accumulation profiles were mapped onto a putative modification pathway deduced from conjugate structures. Mapping revealed that the conjugate metabolites upstream of this pathway accumulated earlier, and those downstream accumulated later during ripening. This result demonstrated that chalcones and flavanones undergo sequential modification as ripening progresses.
TL;DR: A reversed-phase high-performance liquid chromatography method was developed and it was clearly demonstrated that the 2'-hydroxychalcone was involved as intermediate in the on-column and off-column enantiomerization process of flavanone.
TL;DR: As a result of biotransformation of flavanone by the strain Aspergillus niger MB and by the wild strain Penicillium chermesinum 113 the products of hydroxylation at C-6 and C-4′ were obtained.
Abstract: As a result of biotransformation of flavanone ( 1 ) by the strain Aspergillus niger MB (being the UV mutant) and by the wild strain Penicillium chermesinum 113 the products of hydroxylation at C-6 ( 2 ) and C-4′ ( 5 ) were obtained. Additionally, three dihydrochalcones with hydroxyl groups at C-2′ ( 4 ), C-2′ and C-5′ ( 3 ) and C-2′ and C-4 ( 6 ) were formed.
TL;DR: Results suggest that prenyl and methoxy groups on the B ring contribute to the inhibitory activity of flavanones against PTP1B.
TL;DR: All compounds, except 12, were isolated for the first time from this plant and structures of these compounds were identified on the basis of spectroscopic techniques, including 2D NMR.
TL;DR: Acteoside was determined to be the most toxic of the compounds tested on BY-2 cells, diplacone on the K562 cell line, and some aspects of the relationship between the flavanone skeleton substitution and the metabolic activation necessary for a toxic effect are discussed.
Abstract: The newly discovered 5,7-dihydroxy-6-geranylchromone ( 1) was isolated from PAULOWNIA TOMENTOSA fruit and subsequently characterized. The structure of the isolated compound was elucidated on the basis of extensive NMR experiments including HMQC, HMBC, COSY, and NOESY, as well as HR-MS, IR, and UV. The cytotoxicity of 1 was evaluated using a plant cell model represented by tobacco BY-2 cells. The other phytoconstituents ( 2 - 8) previously isolated from P. TOMENTOSA were similarly evaluated together with the known flavanones 10 and 11. The cytotoxicity (human erythro-leukaemia cell line K562) and activity on erythroid differentiation of compounds 2 - 9 and 12 and 13 have also been evaluated. Acteoside ( 2) was determined to be the most toxic of the compounds tested on BY-2 cells, diplacone ( 6) on the K562 cell line. Some aspects of the relationship between the flavanone skeleton substitution and the metabolic activation necessary for a toxic effect are discussed.
TL;DR: Results indicates that proton-driven active transport is commonly participated in the absorption of flavanone in general, and that its transport is presumed to be unique other than MCT-mediated transport for absorption of phenolic acids (PAs), sodium-dependent MCT (SMCT) nor anion exchanger- mediated transport.
Journal Article•
TL;DR: Three F3H cDNAs from Oryza sativa were cloned by RT-PCR and expressed in E. coli as gluthatione S-transferase (GST) fusion proteins to find Flavanone 3beta-hydroxylase could be a useful target for flavonoid metabolic engineering in rice.
Abstract: Flavanone 3beta-hydroxylases (F3H) are key enzymes in the synthesis of flavonol and anthocyanin. In this study, three F3H cDNAs from Oryza sativa (OsF3H-1 approximately 3) were cloned by RT-PCR and expressed in E. coli as gluthatione S-transferase (GST) fusion proteins. The purified recombinant OsF3Hs used flavanone, naringenin and eriodictyol as substrates. The reaction products with naringen and eriodictyol were determined by nuclear magnetic resonance spectroscopy to be dihydrokaempferol and taxifolin, respectively. OsF3H-1 had the highest enzymatic activity whereas the overall expression of OsF3H-2 was highest in all tissues except seeds. Flavanone 3beta-hydroxylase could be a useful target for flavonoid metabolic engineering in rice.
TL;DR: Support vector machine (SVM) was applied to predict vasorelaxation effect of different structural molecules, and structure-activity relationship (SAR) analysis revealed that flavanone derivatives showed the most potent activities, while flavone and chalcone derivatives exhibited medium activities.