Nonlinear relationship between enteric-coated mycophenolate sodium dose and mycophenolic acid exposure in Han kidney transplantation recipients

The aim of the research was to investigate the pharmacokinetics (PK) of enteric-coated mycophenolate sodium (EC-MPS) by quantification of the active metabolite of mycophenolic acid (MPA) after multiple escalating oral doses in Han kidney transplant recipients. A total of 28 Han postoperative kidney transplant recipients were given a multiple-dose of 540, 720 or 900 mg of EC-MPS two times a day in combination with tacrolimus for 6 days. Blood specimens were collected at each time point from 0 to 12 h after EC-MPS administration. MPA plasma concentrations were measured by UPLCUV. The relationship between the EC-MPS dose and its PK parameters was assessed. In the range from 540 to 900 mg, C_max and AUC_012h did not increase with dose escalation. The AUC_012h, C_max, C₀ and T_max for the 540 720 and 900 mg doses were not significantly different, respectively (P >0.05). AUC_012 h and C_max were increased less than proportionally with increasing EC-MPS dose levels. Inter-individual variability in AUC_012h, C_max and C₀ were considerable. Nonlinear PK relationships were found from the doses of 540–900 mg of EC-MPS.     

Effect of non-steroidal anti-inflammatory drugs and new fenamate analogues on TRPC4 and TRPC5 channels

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used anti-inflammatory therapeutic agents, among which the fenamate analogues play important roles in regulating intracellular Ca²⁺ transient and ion channels. However, the effect of NSAIDs on TRPC4 and TRPC5 is still unknown. To understand the structure–activity of fenamate analogues on TRPC channels, we have synthesized a series of fenamate analogues and investigated their effects on TRPC4 and TRPC5 channels.Human TRPC4 and TRPC5 cDNAs in tetracycline-regulated vectors were transfected into HEK293 T-REx cells. The whole cell current and Ca²⁺ movement were recorded by patch clamp and calcium imaging, respectively.Flufenamic acid (FFA), mefenamic acid (MFA), niflumic acid (NFA) and diclofenac sodium (DFS) showed inhibition on TRPC4 and TRPC5 channels in a concentration-dependent manner. The potency was FFA > MFA > NFA > DFS. Modification of 2-phenylamino ring by substitution of the trifluoromethyl group in FFA with F, CH₃, OCH₃, OCH₂CH₃, COOH, and NO₂ led to the changes in their channel blocking activity. However, 2-(2′-methoxy-5′-methylphenyl)aminobenzoic acid stimulated TRPC4 and TRPC5 channels. Selective COX1-3 inhibitors (aspirin, celecoxib, acetaminophen, and indomethacin) had no effect on the channels. Longer perfusion (>5 min) with FFA (100 μM) and MFA (100 μM) caused a potentiation of TRPC4 and TRPC5 currents after their initial blocking effects that appeared to be partially mediated by the mitochondrial Ca²⁺ release.Our results suggest that fenamate analogues are direct modulators of TRPC4 and TRPC5 channels. The substitution pattern and conformation of the 2-phenylamino ring could alter their blocking activity, which is important for understanding fenamate pharmacology and new drug development targeting the TRPC channels.     

Ferritin-dependent radical generation in rat liver homogenates

The hypothesis of this study was that mammalian ferritin (FER) has the ability of releasing Fe in the tissue to catalyze the generation of free radicals, such as ascorbyl (A) and hydroxyl radical (OH), that might lead to the damage of FER itself. The rat liver homogenates exhibited an electron paramagnetic resonance (EPR) signal with the spectral features (a_H = 1.88 G, g = 2.0054) of A. The addition to the reaction medium of isolated rat liver FER increased by 3-fold the EPR signal, as compared to the recorded value in its absence. Isolated microsomes from rat liver incubated during 10 min showed a signal with the spectral features (a_H = 15 G, g = 2.0062) of OH. The addition of FER in the presence of either ethylenediamine-tetraacetic acid (EDTA) or adenosine-5′-triphosphate (ATP) significantly increased the recorded spectra. The labile Fe pool (LIP) in the homogenate was assessed by EPR. The rat liver homogenates exhibited an EPR signal with the spectral features (g = 4.3) of the Fe²⁺ and was significantly increased by the addition of FER (3-fold). The oxidation profile of the isolated FER from rat liver was analyzed after incubation with 10 mM ascorbate (AH^?). A drastic increase in the width of the band suggested alterations to the protein structure. The FER content of tryptophan (Trp) and thiols was significantly lower when the incubation was performed in the presence of AH^? as compared to the recorded effect in its absence. The data in tissue homogenates presented here showed that radical generation is associated to FER Fe release, and moreover that the FER protein itself was affected during this process.     

Hydroxyl radical induced by lipid in Maillard reaction model system promotes diet-derived Nε-carboxymethyllysine formation

N_ε-carboxymethyllysine (CML) is commonly found in food, and is considered as a potential hazard to human health. However, the effect of lipids on CML formation in Maillard reaction is still not clarified. In this study, the content of diet-derived CML and its key intermediates, epsilon-fructoselysine (FL) and glyoxal (GO), is determined with high performance liquid chromatography mass spectrum (HPLC-MS) in model system containing lipid compounds. According to the results, hydroxyl radical (OH) induced by Fenton reagent can promote the three pathways of CML formation. Moreover, in the Maillard reaction system, linoleic acid (Lin), oleic acid (Ole) and glycerol trioleate (Tri) can induce more OH, which promotes CML formation. Their level of promoting CML formation is in the order of Ole > Lin > Tri. On the contrary, glycerol (Gly) can scavenge OH, which inhibit the CML formation. Finally, it is proved that FL content and GO content decreases with heating time in model system, while CML content increases with heating time. Thus, it is concluded that in the Maillard reaction system lipids can induce more OH, which promotes the conversion from FL and GO to CML. Our research may contribute to the development of inhibitory methods for diet-derived CML by scavenging OH.     

The co-application effects of fullerene and ascorbic acid on UV-B irradiated mouse skin

The role of fullerene as a pro-oxidant or anti-oxidant in Ultraviolet B ray (UV-B)-induced disorders in mouse skin was investigated. Fullerene gave no photo-toxic effect to UV-B-irradiated mouse skin. Since erythema was concentrated at the pore circumference in a UV-B irradiation experiment in mouse skin, the sebaceous gland pairs was strongly implicated as a site for the generation of reactive oxygen species (ROS). In a histological evaluation of the skin stained with CH₃MDFDA (ROS index) and YO-Pro-1 (apoptosis index), the fluorescence intensity of a sebaceous gland significantly increased with UV-B irradiation. With the application of fullerene to UV-irradiated mouse skin, no toxicity was recognized in comparison with the control, and erythema, the ROS index, and the apoptosis index decrease with the application of fullerene. Ascorbyl radical (AA) increased with the application of ascorbate (AA) to UV-B-irradiated mouse skin, and AA decreased with the application of fullerene. The co-application of AA and fullerene, which suppressed AA in vitro, significantly suppressed erythema, and also suppressed both the ROS index and apoptosis index in mouse skin after UV-B irradiation. In both mouse skin at 48 h after UV-B irradiation and in an attempt to reproduce this phenomenon artificially in vitro, a similar high AA peak (AA/H > 4) was observed in electron spin resonance (ESR) charts. The binding of fullerene with AA impairs the Fenton reaction between AA and Fe-protein based on the observation of ascorbate-specific UV absorption and a linear equation for the calibration curve. Therefore, fullerene may impair the intercalation of AA to a heme pocket by binding with AA. These results suggest that the co-application of AA and fullerene is effective against oxidative skin damage caused by UV-B irradiation, and the development of an AA inhibitor such as fullerene should be useful for reducing organ damage associated with Fe-protein oxidation.     

Angolan Cymbopogon citratus used for therapeutic benefits: Nutritional composition and influence of solvents in phytochemicals content and antioxidant activity of leaf extracts

Folk medicine is a relevant and effective part of indigenous healthcare systems which are, in practice, totally dependent on traditional healers. An outstanding coincidence between indigenous medicinal plant uses and scientifically proved pharmacological properties of several phytochemicals has been observed along the years.This work focused on the leaves of a medicinal plant traditionally used for therapeutic benefits (Angolan Cymbopogon citratus), in order to evaluate their nutritional value. The bioactive phytochemical composition and antioxidant activity of leaf extracts prepared with different solvents (water, methanol and ethanol) were also evaluated.The plant leaves contained ∼60% of carbohydrates, protein (∼20%), fat (∼5%), ash (∼4%) and moisture (∼9%). The phytochemicals screening revealed the presence of tannins, flavonoids, and terpenoids in all extracts. Methanolic extracts also contained alkaloids and steroids. Several methods were used to evaluate total antioxidant capacity of the different extracts (DPPH, NO, and H₂O₂ scavenging assays, reducing power, and FRAP). Ethanolic extracts presented a significantly higher antioxidant activity (p < 0.05) except for FRAP, in which the best results were achieved by the aqueous extracts. Methanolic extracts showed the lowest radical scavenging activities for both DPPH and NO radicals.     

Flavanols from the Camellia sinensis var. assamica and their hypoglycemic and hypolipidemic activities

α-Glucosidase and lipase inhibitors play important roles in the treatment of hyperglycaemia and dyslipidemia. To identify novel naturally occurring inhibitors, a bioactivity-guided phytochemical research was performed on the pu-erh tea. One new flavanol, named (–)-epicatechin-3-O-(Z)-coumarate (1), and 16 known analogs (217) were isolated from the aqueous extract of the pu-erh tea. Their structures were determined by spectroscopic and chemical methods. Furthermore, the water extract of pu-erh tea and its fractions exhibited inhibitory activities against α-glucosidases and lipases in vitro; compound 15 showed moderate inhibitory effect against sucrase with an IC₅₀ value of 32.5 μmol/L and significant inhibitory effect against maltase with an IC₅₀ value of 1.3 μmol/L. Compounds 8, 10, 11 and 15 displayed moderate activity against a lipase with IC₅₀ values of 16.0, 13.6, 19.8, and 13.3 μmol/L, respectively.     

Nine compounds from the Root Bark of Lycium chinense and their anti-inflammatory activities

Two new compounds, named lyciumlignan D (1) and lyciumphenyl propanoid A (2), along with seven known compounds, were isolated from the root bark of Lycium chinense. Their structures were elucidated using spectroscopic data (UV, IR, HR-ESI-MS, 1D and 2D NMR, CD), as well as by comparison with those of the literature. Compounds 39 were isolated from this genus for the first time. In the in vitro assay, compounds 3, 6, and 7 exhibited stronger anti-inflammatory effects than the positive control curcumin at a concentration of 10 μmol/L.     

Chemical composition and bioactivities of flavonoids-rich extract from Davallia cylindrica Ching

The flavonoids profiles and bioactivities of flavonoids-rich extract from Davallia cylindrica Ching were investigated. The total flavonoids content in D. cylindrica was determined as about 164.41 mg/g. The main flavonoids in D. cylindrica were tentatively identified as quercetin-3-O-rutinoside, quercetin 7-O-glucoside, quercetin 7-O-glucoside, kaempferol 3-O-rutinoside, and quercitrin by UV and ESI-MS spectra. Flavonoids-rich extract (0.258 mg/ml) from D. cylindrica showed similar or higher free radical (O₂⁻, DPPH and ABTS) scavenging potential with that of rutin (0.25 mg/ml). The reducing power of flavonoids-rich extract (0.258 mg/ml) was slightly stronger than that of 0.25 mg/ml rutin. The flavonoids extract from D. cylindrica exhibited cytotoxic effects on A549 cells. It exhibited a dose-dependent inhibition against acetylcholinesterase.     

Acute iron overload and oxidative stress in brain

An in vivo model in rat was developed by intraperitoneally administration of Fe-dextran to study oxidative stress triggered by Fe-overload in rat brain. Total Fe levels, as well as the labile iron pool (LIP) concentration, in brain from rats subjected to Fe-overload were markedly increased over control values, 6 h after Fe administration. In this in vivo Fe overload model, the ascorbyl (A)/ascorbate (AH^?) ratio, taken as oxidative stress index, was assessed. The A/AH^? ratio in brain was significantly higher in Fe-dextran group, in relation to values in control rats. Brain lipid peroxidation indexes, thiobarbituric acid reactive substances (TBARS) generation rate and lipid radical (LR) content detected by Electron Paramagnetic Resonance (EPR), in Fe-dextran supplemented rats were similar to control values. However, values of nuclear factor-kappaB deoxyribonucleic acid (NFκB DNA) binding activity were significantly increased (30%) after 8 h of Fe administration, and catalase (CAT) activity was significantly enhanced (62%) 21 h after Fe administration. Significant enhancements in Fe content in cortex (2.4 fold), hippocampus (1.6 fold) and striatum (2.9 fold), were found at 6 h after Fe administration. CAT activity was significantly increased after 8 h of Fe administration in cortex, hippocampus and striatum (1.4 fold, 86, and 47%, respectively). Fe response in the whole brain seems to lead to enhanced NF-κB DNA binding activity, which may contribute to limit oxygen reactive species-dependent damage by effects on the antioxidant enzyme CAT activity. Moreover, data shown here clearly indicate that even though Fe increased in several isolated brain areas, this parameter was more drastically enhanced in striatum than in cortex and hippocampus. However, comparison among the net increase in LR generation rate, in different brain areas, showed enhancements in cortex lipid peroxidation, without changes in striatum and hippocampus LR generation rate after 6 h of Fe overload. This information has potential clinical relevance, as it could be the key to understand specific brain damage occurring in conditions of Fe overload.     

Polyphenolic constituents of methanolic and aqueous extracts of Vitex negundo render protection to Hep3B cells against oxidative cytotoxicity

This study was aimed at investigating the phenolic constituents of methanolic and aqueous extracts of Vitex negundo in context of antioxidant potential and inhibition of oxidative stress-induced cytotoxicity. Antioxidant efficacies of both extracts were estimated by their abilities to scavenge DPPH and to reduce Fe⁺³ to Fe⁺². Their protective potential against H₂O₂-driven oxidative damage to cells were evaluated by XTT assay in Hep3B (human hepatoma) cells. Total phenolic content of both extracts were estimated, and were tested for correlation with antioxidant potential and protection against oxidative cytotoxicity. Polyphenolic levels in both extracts showed significant (P < 0.05) positive correlations with DPPH scavenging, Fe⁺³–Fe⁺² reduction and percentage decrease in H₂O₂-induced cytotoxicity. Major phenolic compounds in the extracts were identified by HPLC. It was concluded that both V. negundo extracts hold considerable potential as antitheses of free radical toxicity by virtue of their polyphenolic constituents, and might have significant clinical roles in prospect.     

Mechanisms involved in the in vitro contractile dysfunction induced by different concentrations of ferrous iron in the rat myocardium

Iron intoxication is related to reactive oxygen species (ROS) production and organic damage including the cardiovascular system, and is a leading cause of poisoning deaths in children. In this study we examined whether a range of ferrous iron (Fe(2 +)) concentrations can interfere differently on the myocardial mechanics, investigating the ROS-mediated effects. Developed force of isolated rat papillary muscles was depressed with a concentration- and time-dependency by Fe(2 +) 100–1000 μM. The contractile response to Ca(2 +) was reduced, but it was partially reversed by co-incubation with catalase and DMSO, but not TEMPOL. In agreement, in situ detection of OH was increased by Fe(2 +) whereas O₂⁻ was unchanged. The myosin-ATPase activity was significantly decreased. Contractions dependent on the sarcolemal Ca(2 +) influx were impaired only by Fe(2 +) 1000 μM, and antioxidants had no effect. In skinned fibers, Fe(2 +) reduced the pCa-force relationship, and pCa50 was right-shifted by 0.55. In conclusion, iron overload can acutely impair myocardial contractility by reducing myosin-ATPase activity and myofibrillar Ca(2 +) sensitivity. These effects are mediated by local production of OH and H₂O₂. Nevertheless, in a such high concentration as 1000 μM, Fe(2 +) appears to depress force also by reducing Ca(2 +) influx, probably due to a competition at Ca(2 +) channels.     

Effects of patulin on adenosine triphosphatase activities in the mouse.

Patulin (4-hydroxy-4H-furol3,2clpyran-2(6H)-one), a toxic metabolite of various species of Aspergillus and Penicillium, differentially inhibited (in vitro) the Na⁺K⁺-activated and the oligomycin-sensitive and insensitive Mg²⁺-adenosine triphosphatase activities of mouse brain, kidney, and liver fractions containing nerve endings, mitochondria, and endoplasmic reticulum (B), and microsomal preparations (C) from these tissues. A dose-dependent inhibition of Na⁺K⁺-ATPase activity in brain and kidney tissue fractions B and C was observed with corresponding ID50 (50% inhibition) values of 3.0 and 3.7 × 10^?4m patulin for brain and kidney B fractions and 3.4 and 2.0 × 10^?4m patulin for brain and kidney C fractions, respectively. Oligomycin-sensitive mitochondrial Mg²⁺-ATPase of brain, kidney, and liver also were inhibited by patulin in both preparations but less drastically than by the Na⁺K⁺-ATPase system. Oligomycin-insensitive Mg²⁺ activities of brain and kidney were only slightly affected with computed ID50 values of 1.0 and 2.0 × 10^?3m patulin for B fractions and 3.0 and 6.0 × 10^?3m patulin for C fractions, respectively. In vivo oligomycin-sensitive Mg²⁺ ATPase activities in B preparations from liver and kidneys of mice pretreated with 7.5 mg/kg were inhibited 52 and 28%, respectively, after 48 hr. Furthermore, kidney Na⁺K⁺-ATPase activity from the same preprations was significantly correspondingly inhibited. Although oligomycin-sensitive and Na⁺K⁺-ATPase activities were not affected in brain, oligomycin-insensitive ATPase activity was slightly reduced in vivo. Thus, in vitro and in vivo results suggest possible patulin-mediated effects in the mouse through disruption of adenosine triphosphatase systems.     

Potent inhibition of human neutrophil activations by bractelactone,a novel chalcone from Fissistigma bracteolatum

Fissistigma bracteolatum is widely used in traditional medicine to treat inflammatory diseases. However, its active components and mechanisms of action remain unclear. In this study, (3Z)-6,7-dihydroxy-4-methoxy-3-(phenylmethylidene)-5-(3-phenylpropanoyl)-1-benzofuran-2(3H) (bractelactone), a novel chalcone from F. bracteolatum, showed potent inhibitory effects against superoxide anion (O₂^?) production, elastase release, and CD11b expression in formyl-l-methionyl-l-leucyl-l-phenylalanine (FMLP)-induced human neutrophils. However, bractelactone showed only weak inhibition of phorbol myristate acetate-caused O₂^? production. The peak cytosolic calcium concentration ([Ca^2 +]_i) was unaltered by bractelactone in FMLP-induced neutrophils, but the decay time of [Ca^2 +]_i was significantly shortened. In a calcium-free solution, changes in [Ca^2 +]_i caused by the addition of extracellular Ca^2 + were inhibited by bractelactone in FMLP-activated cells. In addition, bractelactone did not alter the phosphorylation of p38 MAPK, ERK, JNK, or AKT or the concentration of cAMP. These results suggest that bractelactone selectively inhibits store-operated calcium entry (SOCE). In agreement with this concept, bractelactone suppressed sustained [Ca^2 +]_i changes in thapsigargin-activated neutrophils. Furthermore, bractelactone did not alter FMLP-induced formation of inositol 1,4,5-triphosphate. Taken together, our results demonstrate that the anti-inflammatory effects of bractelactone, an active ingredient of F. bracteolatum, in human neutrophils are through the selective inhibition of SOCE.     

Bioactive A-ring rearranged limonoids from the root barks of Walsura robusta

Screening active natural products, rapid identification, and accurate isolation are of great important for modern natural lead compounds discovery¹. We hereby reported the isolation of seven new neotecleanin-type limonoids (17), seven new limonoids with 5-oxatricyclo[5.4.0.11., 4.]hendecane ring system (814), and two new precursors (1516) together with four known limonoids (1720) from the root barks of Walsura robusta. Their structures, including their absolute configurations, were elucidated based on analyses of HR-ESI-MS, 1D/2D NMR, ECD spectrum calculations and single-crystal X-ray diffraction techniques. Compounds 2, 8, 9, 11, 13, 14, 18 showed significant anti-inflammatory activities in LPS-induced RAW 264.7 cell line, BV2 microglial cells, and Propionibacterium acnes-stimulated THP-1 human monocytic cells. Walrobsin M (11) exhibited anti-inflammatory activity with IC₅₀ value of 7.96±0.36 μmol/L, and down-regulated phosphorylation levels of ERK and p38 in a dose-dependent manner.     

Evaluation of radioprotective efficacy and possible mechanism of action of Aloe gel

The present study was undertaken to determine the optimum effective dose, dose reduction factor (DRF) and possible mechanism of action of Aloe gel. Three different doses of gel (250, 500 and 750 mg/kg body weight) were tested against 8 Gy induced damage in Swiss albino mice. A dose of 750 mg/kg body weight of Aloe was found the most effective while, 250 mg/kg body weight was the least effective in providing protection, as observed in the form of higher concentrations of blood GSH and vitamin C and lower level of serum LPO than irradiated animals at 1 h post irradiation and higher percent of survivors up to day 30 post irradiation.Treatment of mice with Aloe before irradiation with different doses of gamma radiation (6–12 Gy) delayed the onset and reduced the severity of signs of radiation sickness. The LD_50/30 was calculated as 6.77 and 10 Gy for untreated irradiated and Aloe treated irradiated animals, respectively and its dose reduction factor was also calculated as 1.47. Aloe gel scavenged the free radicals, DPPH, ABTS⁺ and NO in a concentration dependent manner in vitro and therefore, scavenging of free radicals seems to be its important mechanism of action.     

Flavonoids profiles,antioxidant, acetylcholinesterase inhibition activities of extract from Dryoathyrium boryanum (Willd.) Ching

The profiles and bioactivities of flavonoids extracted from Dryoathyrium boryanum (Willd.) Ching were investigated. The total flavonoids content in extract from D. boryanum is about 145.8 mg/g. By means of HPLC–DAD–ESI–MS, the main flavonoids in D. boryanum were tentatively identified as 3-hydroxyphloretin 6′-O-hexoside, quercetin-7-hexoside, apigenin7-O-glucoside, luteolin 7-O-glucoside, apigenin 7-O-galactoside, acacetin 7-O-(α-D-apio-furanosyl) (1 → 6)-β-d-glucoside, 3-hydroxy phloretin 6-O-hexoside, luteolin-6-C-glucoside. 0.21 mg/ml flavonoids extract from D. boryanum showed very strong superoxide anion radical scavenging potential, which is higher than that of rutin (0.25 mg/ml). The extract (0.21 mg/ml of flavonoids) from D. boryanum exhibited similar DPPH scavenging potential with that of rutin (0.25 mg/ml). However, rutin (0.25 mg/ml) showed a significantly higher reducing power and ABTS scavenging potential than that of 0.21 mg/ml flavonoids extract from D. boryanum. It had no effect on acetylcholinesterase. D. boryanum can be considered as a medicinal plant and the flavonoids from D. boryanum are excellent antioxidants.     

Bactericidal effect of colistin on planktonic Pseudomonas aeruginosa is independent of hydroxyl radical formation

The bactericidal effect of several major types of antibiotics has recently been demonstrated to be dependent on the formation of toxic amounts of hydroxyl radicals (OH) resulting from oxidative stress in metabolically active cells. Since killing by the antimicrobial peptide colistin does not require bacterial metabolic activity, we tested whether the bactericidal effect of colistin depends on the formation of OH. In Pseudomonas aeruginosa cultures, OH-mediated killing by ciprofloxacin was demonstrated by decreased bacterial survival and induction of 3′-(p-hydroxyphenyl) fluorescein (HPF) fluorescence. OH-mediated killing by ciprofloxacin was further confirmed by rescue of cells and reduction of HPF fluorescence due to prevention of OH accumulation by scavenging with thiourea, by chelating with dipyridyl, by decreasing metabolism as well as by anoxic growth. In contrast, no formation of OH was seen in P. aeruginosa during killing by colistin, and prevention of OH accumulation could not rescue P. aeruginosa from killing by colistin. These results therefore demonstrate that the bactericidal activity of colistin on P. aeruginosa is not dependent on oxidative stress. In conclusion, antimicrobial peptides that do not rely on OH formation should be considered for treatment of Gram-negative bacteria growing at low oxygen tension such as in endobronchial mucus and paranasal sinuses in cystic fibrosis patients, in abscesses and in infectious biofilm.     

Characterization of flavonoids from Dryopteris erythrosora and evaluation of their antioxidant,anticancer and acetylcholinesterase inhibition activities

The profiles and bioactivities of flavonoids extracted from Dryopteris erythrosora were investigated. The total flavonoid content in full plant of D. Erythrosora is about 14.33%. The main flavonoids in D. Erythrosora were identified as gliricidin 7-O-hexoside, apigenin7-O-glucoside, quercetin 7-O-rutinoside, quercetin 7-O-galactoside, keampferol 7-O-gentiobioside, keampferol-3-O-rutinoside, myricetin 3-O-rhamnoside and quercitrin by means of HPLC-DAD–ESI-MS. Flavonoids (0.36 mg/ml) extract from D. erythrosora showed similar 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS), superoxide anion scavenging potential and ferric reducing antioxidant potential (FRAP) with that of rutin (0.80 mg/ml). However, the antioxidant power by FRAP assay of 0.36 mg/ml flavonoids extract from D. erythrosora was much weaker than that of 0.80 mg/ml rutin. Moreover, the flavonoids extract from D. erythrosora showed obvious cytotoxic effects on A549 cells. The antioxidant activities of flavonoids extracts from 69 ferns showed a significant reciprocal proportion to the total flavonoids contents. The flavonoids extract from D. erythrosora exhibited a dose-dependent inhibition against acetylcholinesterase. Moreover, the anticancer activity slightly increased with improving antioxidant potential of fern flavonoids. Fern flavonoids are excellent function foods.