A new isoprenylated stilbene, flavestinK (1) together with two known isoprenylated stilbenes, flavestin B (2), flavestin G (3), and two isoprenilated flavanones, 4-O-methyl-8-isoprenylnaringenin (4) and 8-isoprenyl-5,7-dihydroxyflavanone (5) were isolated from the leaves of Macaranga recurvata Gage. All of the structures have been determined based on HRESIMS, 1D and 2D NMR spectral data. All of the isolated compounds were evaluated for their cytotoxicity against three human cancer cells (HeLa, T47D and WiDr). Compound 1 showed higher activity than doxorubicin against HeLa cells with IC₅₀ value of 13.1 µg/mL.
Doxorubicin ; Euphorbiaceae ; Flavanones ; HeLa Cells ; Humans ; Stilbenes

This study was to investigate the chemical constituents from the aerial parts of Thymus przewalskii. The chemical consti-tuents were separated and purified by column chromatography on silica gel, ODS, Sephadex LH-20 and semi-prepared HPLC, and their structures were determined by physicochemical properties and spectroscopic data. Four flavanones were isolated from the ethanol extract of the aerial parts of T. przewalskii, and identified as(2S)-5,6-dihydroxy-7,8,4'-trimethoxyflavanone(1), 5,4'-dihydroxy-6,7-dimethoxyflavanone(2),(2S)-5,4'-dihydroxy-7,8-dimethoxyflavanone(3), sakuranetin(4), respectively. Compound 1 was a new compound and its configuration was determined by CD spectrum, compound 3 was natural product which was isolated for the first time and their configurations were determined by CD spectra. Compound 2 was isolated from the genus Thymus for the first time and compound 4 was isolated from T. przewalskii for the first time. Furthermore, cytotoxicity test was assayed for the four flavanones. They exhibited weak cytotoxicity against human lung cancer cells(A549), with the IC_(50) from 74.5 to 135.6 μmol·L~(-1).
Chromatography, High Pressure Liquid ; Flavanones ; Humans

Naringenin is a natural flavonoid compound with anti-inflammatory, anti-oxidation, anti-viral, anti-atherosclerosis and other pharmacological activities. It is also an important precursor of other flavonoid synthesis and with great value of application. At present, the production of flavonoids such as naringenin by microbial methods has a low yield due to imbalance of metabolic pathways, which greatly limits its industrial application. In this study, a naringenin-producing strain of Saccharomyces cerevisiae Y-01 was used in the research object. The expression levels of 4-coumaric acid: CoA ligase (4CL), chalcone synthase (CHS) and chalcone isomerase (CHI) were controlled by promoter and copy numbers to investigate the quantitative effect of key enzyme expression level on the accumulation level of target products. The results showed that the correlation between naringenin production and 4CL or CHI expression was not significant while there was a positive correlation with the expression level of CHS. Strain Y-04 with high yield of naringenin was obtained by regulating the expression level of chs gene, and the yield was increased by 4.1-folds compared with the original strain Y-01. This study indicated that CHS is a key regulatory target of naringenin synthesis. Rational regulation of CHS expression can significantly promote the accumulation of naringenin. The related results provide an important theoretical reference for the use of metabolic engineering to strengthen microbial synthesis of important flavonoids such as naringenin.
Flavanones ; metabolism ; Metabolic Engineering ; Saccharomyces cerevisiae

In this study,liquiritigenin sulfonation was characterized using recombinant human sulfotransferases( SULTs). The chemical structure of liquiritigenin sulfate was determined by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry( UPLC-Q-TOF-MS/MS). Then model fitting and parameter estimation were performed using the Graphpad Prism V5 software. Various SULT enzymes( SULT1 A1,1 A2,1 A3,1 B1,1 C2,1 C4,1 E1 and 2 A1) were able to catalyze the formation of liquiritigenin-7-O-sulfate. Sulfonation of liquiritigenin-7-hydroxy( 7-OH) by these eight SULT enzymes consistently displayed the classical Michaelis-Menten profile. According to the intrinsic clearance( CLint) value,the sulfonation rates of liquiritigenin-7-OH by expressed SULT enzymes followed the following rank order: SULT1 C4 > SULT1 A3 > SULT1 E1 > SULT1 A1 > SULT1 A2 > SULT1 B1 >SULT1 C2>SULT2 A1. Further,liquiritigenin-7-O-sulfonation was significantly correlated with the SULT1 A3 protein levels( P<0. 05).Then,human embryonic kidney( HEK) 293 cells over expressing SULT1 A3( named as HEK-SULT1 A3 cells) were conducted. As a result,liquiritigenin-7-O-sulfate( L-7-S) was rapidly generated upon incubation of the cells with liquiritigenin. Consistent with SULT1 A3,sulfonation of liquiritigenin-7-OH in HEK-SULT1 A3 cells also followed the Michaelis-Menten kinetics. The derived Vmaxvalues was( 0. 315±0. 009) μmol·min-1·g-1,Kmwas( 7. 04±0. 680) μmol·L^-1,and CLintwas( 0. 045±0. 005) L·min^-1·g^-1. Moreover,the sulfonation characters of liquiritigenin( 7-OH) in SULT1 A3 were strongly correlated with that in HEK-SULT1 A3 cells( P<0. 001).The results indicated that HEK-SULT1 A3 cells have shown the catalytic function of SULT1 A3 enzymes. In conclusion,liquiritigenin was subjected to efficient sulfonation,and SULT1 A3 enzyme plays an important role in the sulfonation of liquiritigenin-7-OH. Significant sulfonation should be the main reason for the low bioavailability of liquiritigenin. In addition,HEK-SULT1 A3 cells were conducted and successfully used to evaluate liquiritigenin sulfonation,which will provide an appropriate tool to accurately depict the sulfonation disposition of liquiritigenin in vivo.
Arylsulfotransferase ; Flavanones/metabolism* ; Humans ; Tandem Mass Spectrometry

To screen and identify the endophytic fungal strains that could promote the accumulation of flavonoids in the callus of Scutellaria baicalensis. Seventeen endophytic fungal strains from S. baicalensis were used to prepare mycelium elicitors and fermentation broth elicitors. Their effects on flavonoid accumulation in S. baicalensis callus were then determined. The results showed that the fermentation broth elicitors of two strains(CL79, CL105) promoted the accumulation of flavonoids. The fermentation broth elicitor of CL79 significantly promoted accumulation of baicalin, wogonoside, baicalein, and wogonin, with the maximum levels increased by 37.8%, 40.4%, 44.7%, and 42.2%(vs. blank), respectively. Similarly, the fermentation broth elicitor of CL105 significantly promoted the accumulation of baicalin, wogonoside, baicalein, and wogonin, with the maximum levels increased by 78.1%, 140.9%, 275.6%, and 208.5%(vs. blank), respectively. CL79 was identified as Alternaria alternata, and CL105 as Fusarium solani. The fermentation broth elicitors of A. alternata CL79 and F. solani CL105 were able to promote the flavonoid accumulation in the callus of S. baicalensis, which enriched the resources of endophytic fungi and provided candidate strains for the development of microbial fertili-zers for improving the quality of S. baicalensis.
Scutellaria baicalensis ; Plant Roots ; Flavanones ; Flavonoids

OBJECTIVETo evaluate the effects of Drynaria fortunei naringin on the total protein content and ultra-structure of human periodontal ligament cells (hPDLCs).

METHODSThrough enzyme digestion combined tissue-culture method, primarily culture and identify the human periodontal ligament cells. Coomassie brilliant blue staining was used to detect the total protein content of hPDLCs with the effects of difference concentration of Drynaria fortunei naringin at difference times. Transmission electron microscope was used to study the ultra-structure of hPDLCs with the effects of Drynaria fortunei naringin.

RESULTSIn vitro, the addition of Drynaria fortunei naringin at dose of 100, 10, 1, 0.1 mg x L(-1) in cultures resulted in an increase of total protein content at the 3rd, 5th, 7th day, but the maximum response was obtained with 1 mg x L(-1) Drynaria fortunei naringin. There were more rough endoplasmic reticulums, mitochodrias and ribosomes in the experimental group than in the control.

CONCLUSIONDrynaria fortunei naringin may stimulate the protein synthesis and metabolism of hPDLCs.

Pinocembrin, belonging to flavanons, was isolated from various plants. Pinocembrin has a variety of pharmacological activities, such as neuroprotective effect, antimicrobial activity, and antioxidant efficacy. Pinocembrin was approved as class I drugs to its phase II clinical trial by CFDA in 2009, mainly used for the treatment of ischemic stroke. As a promising compound, the manufacturing technologies of pinocembrin, including chemical synthesis, extraction from plant and synthetic biology, have attracted many attentions. Compared with the first two technologies, synthetic biology has many advantages, such as environment-friendly and low-cost. Construction of biosynthetic pathway in microorganism offers promising results for large scale pinocembrin production by fermentation after taking lots of effective strategies. This article reviews some of recent strategies in microorganisms to improve the yield, with focus on the selection of appropriate the key enzyme sources, the supply of precursors and cofactors by microorganisms, the choice of substance and the level of the key enzyme expression.
Biosynthetic Pathways ; Fermentation ; Flavanones ; biosynthesis ; Industrial Microbiology ; Plants ; Synthetic Biology

Flavonoids have a variety of biological activities and have important applications in food, medicine, cosmetics, and many other fields. Naringenin is a platform chemical for the biosynthesis of many important flavonoids. Ubiquitination plays a pivotal role in the post-translational modification of proteins and participates in the regulation of cellular activities. Ubiquitinated proteins can be degraded by the ubiquitin-protease system, which is important for maintaining the physiological activities of cells, and may also exert a significant impact on the expression of exogenous proteins. In this study, a real-time in-situ detection system for ubiquitination modification has been established in Saccharomyces cerevisiae by using a fluorescence bimolecular complementation approach. The ubiquitination level of protein was characterized by fluorescence intensity. By using the approach, the potential ubiquitination sites of proteins involved in the naringenin biosynthesis pathway have been obtained. The lysine residues of the relevant ubiquitination sites were mutated to arginine to reduce the ubiquitination level. The mutants of tyrosine ammonia-lyase (FjTAL) and chalcone synthase (SjCHS, SmCHS) showed decreased fluorescence, suggested that a decreased ubiquitination level. After fermentation verification, the S. cerevisiae expressing tyrosine ammonia-lyase FjTAL mutant FjTAL-K487R accumulated 74.2 mg/L p-coumaric acid at 72 h, which was 32.3% higher than that of the original FjTAL. The strains expressing chalcone synthase mutants showed no significant change in the titer of naringenin. The results showed that mutation of the potential ubiquitination sites of proteins involved in the naringenin biosynthesis pathway could increase the titer of p-coumaric acid and have positive effect on naringenin biosynthesis.
Biosynthetic Pathways ; Flavanones/metabolism* ; Saccharomyces cerevisiae/metabolism* ; Ubiquitination

OBJECTIVE: To explore the effects of Eriodictyol to the growth, apoptosis and oxidative stress of Burkitt lymphoma (BL) cells and phosphorylation of protein kinase B (AKT) in children. METHODS: The effects of Eriodictyol (0, 1.25, 2.5, 5, 10, 20, 40, 80, 160, 320 μmol/L) to viability of BL cell line DG-75 cells were detected by CCK-8. The effects of Eriodictyol (0, 10, 20, 40 μmol/L) to the proliferation activity of DG-75, apoptosis rate, levels of apoptosis-related proteins, oxidative stress indexes ［superoxide dismutase (SOD), malondialdehyde (MDA)］, mitochondrial membrane potential (MMP) and phosphorylation level of phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycinm (mTOR) were detected by clony formation assay and Wester blot. RESULTS: When the treatment concentration of Eriodictyol was 20 μmol/L, the proliferation activity of the cells was decreased (P<0.05). The concentrations at 10, 20, 40 μmol/L were selected for subsequent experiments. Compared with 0 μmol/L Eriodictyol, the proliferation activity of DG-75, SOD activity, MMP, phosphorylation levels of PI3K, AKT and mTOR in 20 and 40 μmol/L Eriodictyol treatment groups were significantly decreased (P<0.05), while cells apoptosis rate, Cleaved-Caspase-3/Caspase-3, Bax/Bcl-2 and MDA level were significantly increased (P<0.05). CONCLUSION Eriodictyol may promote the mitochondrial apoptosis pathway by inhibiting the abnormal activation of PI3K/AKT/mTOR to reduce the proliferation activity of DG-75, and inhibit oxidative stress response to increase the apoptosis rate and play anti-tumor roles.
Apoptosis ; Flavanones ; Phosphatidylinositol 3-Kinases/metabolism* ; Signal Transduction

PURPOSE: The purpose of this study was to investigate the relationship between dietary flavonoids intake and metabolic syndrome (MetS) in Korean women with polycystic ovary syndrome (PCOS). METHODS: A total of 223 subjects (mean age; 27.3 +/- 4.2 yrs, range; 17-38 yrs) were divided into the MetS group (n = 27) and non-MetS group (n = 196). Dietary intake data were assessed by 24-hour recall method for two non-consecutive days and the average of the two days was used to estimate the usual dietary intake. Dietary habits were assessed using the Mini Dietary Assessment (MDA) score. We analyzed the intakes of six flavonoid classes (anthocyanidins, flavan-3-ols, flavanones, flavones, flavonols, and iso-flavones) using a flavonoids database. RESULTS: After adjustment for age, total energy intake, alcohol consumption, smok-ing, regular exercise, and oral contraceptive use, dietary flavonols intake was significantly lower in the MetS group (5.1 +/- 2.4 mg/d) than in the non-MetS group (8.9 +/- 2.8 mg/d) (p = 0.0472). Intakes of other flavonoids except for flavonols did not differ between the two groups. In MDA scores, significant differences were observed only for that related to daily con-sumption of fruit or fruit juice (p = 0.0180). A significant inverse relationship was observed between flavonols intake and the risk of MetS (4th vs. 1st quartile, OR = 0.11, 95% CI = 0.02-0.62, p for trend = 0.0131). CONCLUSION: These results sug-gest that higher intake of flavonols may be beneficial for MetS in PCOS women.
Alcohol Drinking ; Energy Intake ; Female ; Flavanones ; Flavones ; Flavonoids* ; Flavonols ; Food Habits ; Fruit ; Humans ; Polycystic Ovary Syndrome*