Extraction and quantification of polyphenols from kinnow (Citrus reticulate L.) peel using ultrasound and maceration techniques

An investigation was carried out to extract polyphenols from the peel of kinnow (Citrus reticulate L.) by maceration and ultrasound-assisted extraction (UAE) techniques. The antioxidant potential of these polyphenols was evaluated using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and superoxide radical scavenging assays; and their antimicrobial activity was assessed against bacterial strains Staphyloccoccus aureus, Bacillus cereus, and Salmonella typhimurium. The highest extraction yield was obtained through the solvent ethanol at 80% concentration level, whereas UAE was a more efficient technique and yielded comparatively higher polyphenol contents than maceration. Maximum polyphenols were extracted with 80% methanol [32.48 mg gallic acid equivalent (GAE)/g extract] using UAE, whereas minimum phenolics (8.64 mg GAE/g extract) were obtained with 80% ethyl acetate through the maceration technique. Elevated antioxidant activity of kinnow peel extracts was exhibited in three antioxidant assays, where 80% methanolic extracts showed the highest antioxidant activity (27.67 ± 1.11mM/100 g for FRAP) and the highest scavenging activity, 72.83 ± 0.65% and 64.80 ± 0.91% for DPPH and superoxide anion radical assays, respectively. Strong correlations between total polyphenols and antioxidant activity were recorded. Eleven phenolic compounds—including five phenolic acids and six flavonoids—were identified and quantified by high performance liquid chromatography. Ferulic acid and hesperidin were the most abundant compounds whereas caffeic acid was the least abundant phenolic compound in kinnow peel extracts. Maximum inhibition zone was recorded against S. aureus (16.00 ± 0.58 mm) whereas minimum inhibition zone was noted against S. typhimurium (9.00 ± 1.16 mm). It was concluded that kinnow mandarin peels, being a potential source of phenolic compounds with antioxidant and antimicrobial properties, may be used as an ingredient for the preparation of functional foods.     

Total contents of arsenic and associated health risks in edible mushrooms,mushroom supplements and growth substrates from Galicia (NW Spain)

The levels of arsenic (As) in the main commercial species of mushrooms present in Galicia, in their growth substrates, and mushroom supplements have been analysed by ICP-MS, with the intention of assessing potential health risks involved with their consumption.The mean concentrations of As in wild and cultivated mushrooms was 0.27 mg/kg dw, in mushroom supplements 0.40 mg/kg dw, in soils 5.10 mg/kg dw, and in growth substrate 0.51 mg/kg dw.No significant differences were observed between species, although the species Lactarius deliciosus possessed a slightly more elevated mean concentration (at 0.49 mg/kg dw) than the other species investigated. In soils, statistically significant differences (p < 0.05) were observed according to geographic origin. Levels in mushroom supplements, although low, were higher than in wild or cultivated mushrooms.Measured arsenic levels were within the normal range in samples analysed in unpolluted areas. Because of the low As concentrations found in fungi and mushroom supplements from Galicia, and considering the relatively small inclusion of these foods in people’s diet, it can be concluded that there is no toxicological risk of arsenic associated with the consumption of the species of mushrooms analysed or at the dosages indicated for mushroom supplements.     

Comparative study of wild edible mushrooms as sources of antioxidants

The purpose of the study was to explore sixteen of the most popular edible species of wild-growing mushrooms as potential sources of antioxidants. Among the mushrooms tested, the highest total polyphenol contents, exceeding 100 mg/100 g fresh mass, were found in five mushrooms: Boletus chrysenteron, B. edulis, Leccinum scabrum, L. aurantiacum, and Macrolepiota procera. Antioxidant activity was measured with the FRAP, TEAC, DPPH scavenging ability and ferrous ions chelating ability assays. Results of the study show that wild mushrooms vary according to their antioxidant properties. The highest FRAP potentials, exceeding 1 mmol/100 g, were found in five species ofBoletales: Boletus edulis, B. chrysenteron, Leccinum scabrum, L. aurantiacum, and Suillus grevillei. TEAC values were from 1.07 to 4.01 mmol/100 g fresh mass. High TEAC values (>2.3 mmol/100 g) were found in Leccinum scabrum, L. aurantiacum, Macrolepiota procera, Boletus chrysenteron, and B. edulis. The DPPH radical scavenging effectiveness of mushroom extracts, expressed as EC50 values, was in range 2.91-13.86 mg/mL. Scavenging ability was the highest for B. edulis and B. chrysenteron. The metal chelating ability of mushroom extracts expressed as ECso values of chelating ability on ferrous ions were from 8.02 mg/mL in Cantharellus cibarius to 12.10 mg/mL in Suillus luteus. Among the mushrooms tested, Boletus chrysenteron and B. edulis were characterized by high scores of polyphenol contents and antioxidant activity in the FRAP, TEAC, and DPPH assays. These results place these culinary species of wild-growing mushrooms among products with considerable antioxidant potential.     

Protective effect of extract of Crataegus pinnatifida pollen on DNA damage response to oxidative stress

The protective effect of extract of Crataegus pinnatifida (Rosaceae) pollen (ECPP) on the DNA damage response to oxidative stress was investigated and assessed with an alkaline single-cell gel electrophoresis (SCGE) assay and pBR322 plasmid DNA breaks in site-specific and non-site-specific systems. Total phenolic content, total flavonoid content, individual phenolic compounds, antioxidant activities (1,1-diphenyl-2-picrylhydrazyl (DPPH), radical scavenging activity, FRAP, and chelating activity) were also determined. The results showed that ECPP possessed a strong ability to protect DNA from being damaged by hydroxyl radicals in both the site-specific system and the non-site-specific system. It also exhibited a cytoprotection effect in mouse lymphocytes against H₂O₂-induced DNA damage. These protective effects may be related to its high total phenolic content (17.65 ± 0.97 mg GAE/g), total flavonoid content (8.04 ± 0.97 mg rutin/g), strong free radical scavenging activity and considerable ferrous ion chelating ability (14.48 ± 0.21 mg Na₂EDTA/g).     

Juniperus oxycedrus L. subsp. oxycedrus and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. “berries” from Turkey: Comparative evaluation of phenolic profile,antioxidant, cytotoxic and antimicrobial activities

This work aimed to evaluate and compare the phenolic profile and some biological properties of the ripe “berries” methanol extracts of Juniperus oxycedrus L. subsp. oxycedrus (Joo) and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom) from Turkey. The total phenolic content resulted about 3-fold higher in Jom (17.89 ± 0.23 mg GAE/g extract) than in Joo (5.14 ± 0.06 mg GAE/g extract). The HPLC–DAD–ESI–MS analysis revealed a similar flavonoid fingerprint in Joo and Jom, whereas a difference in their quantitative content was found (4632 μg/g extract and 12644 μg/g extract). In addition, three phenolic acids were detected in Jom only (5765 μg/g extract), and protocatechuic acid was the most abundant one. The antioxidant capacity of the extracts was evaluated by different in vitro assays: in the DPPH and in the TBA tests a stronger activity in Jom was highlighted, while Joo exhibited higher reducing power and metal chelating activity. Joo and Jom did not affect HepG2 cell viability and both extracts resulted virtually non-toxic against Artemia salina. The extracts were also studied for their antimicrobial potential, displaying efficacy against Gram-positive bacteria.     

Phytochemical contents and enzyme inhibitory and antioxidant properties of Anethum graveolens L. (dill) samples cultivated under organic and conventional agricultural conditions

Inhibitory effect of the n-hexane, dichloromethane, ethyl acetate, and ethanol extracts from Anethum graveolens L. (dill) cultivated under organic (AG-O) and conventional (AG-C) conditions was tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase at 200 μg mL⁻¹. Their antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), N,N-dimethyl-p-phenylendiamine (DMPD), and nitric oxide (NO) radical scavenging assays as well as ferric ion-chelation capacity, ferric-(FRAP), and phosphomolybdenum-reducing antioxidant power (PRAP). The phytochemical analyses have been performed on both of the plant samples. GC–MS analysis pointed out that α-phellandrene was the main component in both of the essential oils in varying amounts (47.75% for AG-O and 27.94% for AG-C), while oleic acid was the dominant in the fruit oils of two samples (36.39% for AG-O and 53.87% for AG-C). HPLC analysis showed that both of the extracts contained rosmarinic acid as the major phenolic acid. The extracts inhibited BChE at moderate level, while the ethanol extracts exerted remarkable NO scavenging effect. The results emphasize that cultivation conditions may have effect on bioactivity and phytochemical content on plant samples.     

Leaf extracts from Teucrium ramosissimum protect against DNA damage in human lymphoblast cell K562 and enhance antioxidant,antigenotoxic and antiproliferative activity

The in vitro antioxidant, antigenotoxic and antiproliferative activities of Teucrium ramosissimum extracts were investigated. The antioxidant activities of the tested extracts were evaluated through three chemical assays: The Cupric reducing antioxidant capacity, the reducing power and the ferric reducing antioxidant power. TR1 fraction from methanol extract showed the best antioxidant activity evaluated by the CUPRAC, RP and FRAP assays with TEAC values of 4.04, 1.77 and 1.48 μM respectively compared to control. Yet, TR2 fraction exhibited the lowest antioxidant effect with a TEAC values of 1.97, 0.408 and 0.35 μM respectively. All the tested extracts were also found to be effective in protecting plasmid DNA against the strand breakage induced by hydroxyl radicals. Furthermore, the effects of T. ramosissimum extracts on cell proliferation were also examined. The cytotoxic study revealed that methanol extract significantly inhibited the proliferation of K562 cells (IC50 = 150 μg/mL). The antigenotoxic properties of these extracts were investigated by assessing the induction and inhibition of the genotoxicity induced by the direct-acting mutagen, hydrogen peroxide (H₂O₂), using an eukaryotic system; the “Comet assay.” The results showed that all the extracts inhibited the genotoxicity induced by H₂O₂, and particularly TR2 fraction (96.99%) and methanol extract (96.64%).The present study has demonstrated that T. ramosissimum extract possess potent antioxidant, antiproliferative and antigenotoxic activities, which could be derived from compounds such as flavonoids and polyphenols.     

Composition and anti-oxidant,anti-cancer and anti-inflammatory activities of Artemisia herba-alba,Ruta chalpensis L. and Peganum harmala L.

In this study, biological activities of methanolic extracts from Artemisia herba-alba, Ruta chalpensis L. and Peganum harmala L. plants, collected in Centre of Tunisia, were investigated. Results showed an important phenolic composition of Artemisia herba-alba (123.95 ± 4.3 g GAE/kg of dry mass). The extract of this plant showed, using different antioxidant assays (DPPH, ABTS and AAPH/linoleic acid methods) and an IFN-γ/LPS induced RAW 264.7 murine macrophages’ assay, the highest antioxidant (IC50 (DPPH assay) 20.64 ± 0.84 mg/L) and anti-inflammatory (72% inhibition at 150 mg/L) activities, respectively. Excepting Peganum harmala L. extract, the two other extracts showed a high anticancer activity against several cell lines (human bladder carcinoma RT112, human laryngeal carcinoma Hep2 and human myelogenous leukemia K562), for A. herba-laba IC50 = 81.59 ± 4.4, 59.05 ± 3.66 and 90.96 mg/L respectively, but not on normal peripheral blood mononuclear cells. All these biological activities are well correlated with the phenolic contents of these extracts. These findings demonstrate the remarkable potential of these plants as valuable source of antioxidants with exhibit original and interesting anti-inflammatory and anticancer capacities.     

Chemical composition of five wild edible mushrooms collected from Southwest China and their antihyperglycemic and antioxidant activity

Evaluation of the chemical composition and antihyperglycemic and antioxidant activity of five wild edible mushrooms (Clitocybe maxima, Catathelasma ventricosum, Stropharia rugoso-annulata, Craterellus cornucopioides and Laccaria amethystea) from Southwest China. The chemical composition assay includes proximate analysis (moisture, ash, crude protein, crude fat, total carbohydrates and total energy), bioactive compounds analysis (total phenolic, flavonoid, ascorbic acid, ergosterol, tocopherol), fatty acid analysis, amino acid analysis, phenolic compounds analysis and mineral analysis of these mushrooms. Furthermore, assays of α-glucosidase inhibitory and α-amylase inhibitory activity were used for evaluating antihyperglycemic activity of the mushrooms, and assays of reducing power, chelating effect on ferrous ions, scavenging effect on hydroxyl free radicals and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were used for evaluating antioxidant activity of the mushrooms. Based on the results, ethanolic and aqueous extract of these mushroom all showed antihyperglycemic and antioxidant potential. In particular, the aqueous extract of C. ventricosum revealed the highest α-glucosidase inhibitory activity (EC50 value 2.74 μg/mL), DPPH radical scavenging activity (EC50 value 2.86 mg/mL) and reducing power (EC50 value 0.96 mg/mL), while the aqueous extract of L. amethystea showed the highest α-amylase inhibitory activity (EC50 value 4.37 μg/mL) and metal chelating activity (EC50 value 2.13 mg/mL).     

Taxifolin mitigates oxidative DNA damage in vitro and protects zebrafish (Danio rerio) embryos against cadmium toxicity

Taxifolin (TAX) is a natural source of bioflavonoid found in various conifers. In this study, initially we investigated the antioxidant potential of TAX under in vitro assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), ferric-ion reducing power (FRAP) and hydroxyl radical (OH). The activities of DPPH, ABTS, FRAP and OH radical levels were significantly inhibited by TAX with an IC₅₀ values of 16.48, 66.34, 18.17 and 11.42 μg/ml, respectively. Secondly, TAX exhibited a strong protection against OH mediated DNA damage on pUC19 plasmid DNA at 1.0 μg/ml. Finally, we evaluated the protective mechanism of TAX against cadmium intoxicated zebrafish embryos (Danio rerio). We found that embryos exposed to 100 μM Cd exhibited significantly reduced survival, delayed hatching and phenotypic abnormalities at 24, 48, 72 and 96 hours post fertilization (hpf). Similarly, Cd intoxicated embryos showed significantly increased cardiac function (131 beats/min) at 60 hpf. Conversely, treatment with TAX (0.1, 1.0 and 10 μM) significantly enhanced the antioxidant enzyme levels (SOD, CAT, GPx and GR) by reducing the lipid peroxidation (MDA) in zebrafish embryos. Collectively, our results concluded that TAX could act as a potent redox scavenger against oxidative DNA damage and also functions as a crucial suppressor of Cd toxicity in zebrafish embryos.     

Chemistry and functional properties in prevention of neurodegenerative disorders of five Cistus species essential oils

The chemical composition of Cistus creticus, Cistus salvifolius, Cistus libanotis, Cistus monspeliensis and Cistus villosus essential oils has been examined by GC and GC–MS analysis. Height-nine constituents were identified in C. salvifolius oil, sixty in C. creticus, fifty-six in C. libanotis, fifty-four in C. villosus, forty-five in C. monspeliensis. Although the five species belong to the same genus, the composition showed interesting differences. Essential oils were screened also for their potential antioxidant effects (by DPPH, ABTS, FRAP and β-carotene bleaching test) and their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity, useful for prevention and treatment of Alzheimer’s disease. C. monspeliensis exhibited the most promising activity in β-carotene bleaching test (IC₅₀ of 54.7 μg/mL). In FRAP test C. libanotis showed a value of 19.2 μM Fe(II)/g. C. salvifolius showed the highest activity against AChE (IC₅₀ of 58.1 μg/mL) while C. libanotis, C. creticus, C. salvifolius demonstrated a good inhibitory activity against BChE with IC₅₀ values of 23.7, 29.1 and 34.2 μg/mL, respectively. Overall our results could promote the use of the essential oil of different Cistus species as food additives and for formulation of herbal infusion or nutraceutical products.     

Antioxidant activity and hepatoprotective property of leaf extracts of Boerhaavia diffusa Linn against acetaminophen-induced liver damage in rats

Extracts of Boerhaavia diffusa leaves were evaluated for antioxidant and hepatoprotective properties in the acetaminophen-induced liver damage model. Antioxidative evaluation of ethanolic extract gave total phenolic content, total flavonoid content, vitamin C content and vitamin E content and the levels of selenium and zinc as 6.6 ± 0.2 mg/g tannic acid equivalent, 0.092 ± 0.003 mg/g quercetin equivalent, 0.21 ± 0.03 mg/g, 0.054 ± 0.002 mg/g, 0.52 ± 0.05 ppm and 9.28 ± 0.16 ppm, respectively. The DPPH scavenging capacity and the reductive potential were 78.32 ± 2.41% and 0.65 ± 0.02 mg/g ascorbic acid, respectively. Pretreatment with aqueous and ethanolic extracts decreased the activities of alkaline phosphatase, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, and the level of bilirubin in the serum that were elevated by acetaminophen. The two extracts also ameliorated the elevation in the activities of the enzymes in the liver. Acetaminophen intoxication led to reduction in serum and liver albumin levels which were not significantly increased by pretreatment with the extracts. The extracts also protected against acetaminophen induced lipid peroxidation. These results indicated that leaf extracts from B. diffusa possess hepatoprotective property against acetaminophen-induced liver damage which may be mediated through augmentation of antioxidant defenses.     

Assessment of antioxidant,anti-inflammatory,anti-cholinesterase and cytotoxic activities of pomegranate (Punica granatum) leaves

This study evaluated antioxidant, anti-inflammatory, anti-cholinesterase and cytotoxic activities of extracts with different polarities (hexane, dichloromethane, ethyl acetate, ethanol and methanol) obtained from Punica granatum leaves. Total phenolics (8.8–127.3 mg gallic acid equivalent/g dry weight), flavonoids (1.2–76.9 mg quercetin equivalent/g dry weight), tannins (63.7–260.8 mg catechin equivalent/kg dry weight) and anthocyanins (0.41–3.73 mg cyanidin-3-glucoside equivalent/g dry weight) of different extracts were evaluated. The methanolic extract presented a good IC50 by DPPH and ABTS assays (5.62 and 1.31 mg/l respectively). The strongest 5-lipoxygenase (5-LOX), acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition activities were obtained for the ethanol extract (IC50 values of 6.20, 14.83 and 2.65 mg/l, respectively) and the best cytotoxic activity against MCF-7 cells was obtained for the methanol extract (IC50 = 31 mg/l). These important biological activities showed that P. granatum leaves could be a potential source of the active molecules intended for applications in pharmaceutical industry, but only after additional in vivo experiments.     

Anticancer,antioxidant and antibiotic activities of mushroom Ramaria flava

Ramaria flava is a species of edible mushroom with some bioactivity. The anticancer, antioxidant and antibiotic activities and chemical composition of R. flava ethanol extract (EE) were evaluated. The present study exhibited that the EE displayed the strongest inhibitory activity against tumor cell MDA-MB-231 with an IC₅₀ value of 66.54 μg/mL in three tested tumor cell lines, and the inhibition percent was 71.66% at the concentration of 200 μg/mL (MTT assay). The total phenolic compounds varied among four fractions of the EE from 6.66 to 61.01 mg gallic acid equivalent (GAE) per g dry weight. Water fraction exhibited high DPPH and OH radical-scavenging activities with low IC₅₀ values of 5.86 and 18.08 μg/mL, respectively. Meanwhile, three phenolic compounds from water fraction were also identified by HPLC. The antibiotic activities of the EE were evaluated against three microorganisms and three fungi strains by means of the agar well diffusion method and the poisoned medium technique, respectively. The EE also showed moderate antibiotic activities. These results suggest that R. flava could hold a good potential source for human health.     

Antioxidant and anti-diabetic potential of Passiflora alata Curtis aqueous leaves extract in type 1 diabetes mellitus (NOD-mice)

Leaves of Passiflora alata Curtis were characterized for their antioxidant capacity. Antioxidant analyses of DPPH, FRAP, ABTS, ORAC and phenolic compounds were made in three different extracts: aqueous, methanol/acetone and ethanol. Aqueous extract was found to be the best solvent for recovery of phenolic compounds and antioxidant activity, when compared with methanol/acetone and ethanol. To study the anti-inflammatory properties of this extract in experimental type 1 diabetes, NOD mice were divided into two groups: the P. alata group, treated with aqueous extract of P. alata Curtis, and a non-treated control group, followed by diabetes expression analysis. The consumption of aqueous extract and water ad libitum lasted 28 weeks. The treated-group presented a decrease in diabetes incidence, a low quantity of infiltrative cells in pancreatic islets and increased glutathione in the kidney and liver (p < 0.05), when compared with the diabetic and non-diabetic control-groups. In conclusion, our results suggest that the consumption of aqueous extract of P. alata may be considered a good source of natural antioxidants and compounds found in its composition can act as anti-inflammatory agents, helping in the control of diabetes.     

Studies on the bioactivity of aqueous extract of pu-erh tea and its fractions: In vitro antioxidant activity and α-glycosidase inhibitory property,and their effect on postprandial hyperglycemia in diabetic mice

Despite abundant research that has been carried out on the potential health benefits of pu-erh tea, no consensus till now, has been reached on which constituent is mainly responsible for its bioactivity. In this work, the aqueous extract (AE) and its fraction enriched with active constituents were prepared from pu-erh tea, and their bioactivities were investigated. It was found that tea polyphenols (TP), tea polysaccharides (TPS), caffeine (Caf), protein (Pro), amino acids (AA) were accumulated in several fractions after solvent extraction despite not being separated completely. Meanwhile, 95% ethanol precipitate (EP) and ethyl acetate fraction (EF) possessed remarkable antioxidant activity and potent inhibitory effects against α-glycosidase in vitro. Furthermore, all the extracts (50 mg/kg BW) showed a significant (p < 0.05) effect on postprandial hyperglycemia in diabetic mice as compared with a model group, and the suppression of EP was not significantly (p > 0.05) different from that of acarbose at the same dosage (50 mg/kg BW), which indicate that these fractions could be developed as potential anti-diabetic agents.     

Inhibitory effect of Nymphaea pubescens Willd. flower extract on carrageenan-induced inflammation and CCl4-induced hepatotoxicity in rats

Nymphaea pubescens Willd. is used as ingredient of ethnic diet and folk medicine in South-East Asia. The water (NPW), methanol (NPM) and chloroform (NPC) extracts of N. pubescens flowers were investigated for NO, ${\text{O}}_2^{\text{<mglyph src="https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/rad"></mglyph>}-}$ and DPPH radical scavenging and iron chelating activities in vitro. NPW was found to be the most potent free radical scavenger (EC₅₀ < 100 μg/mL) whereas NPC did not show EC₅₀ at 500 μg/mL. Therefore, NPW was selected for further studies on anti-inflammatory and hepatoprotective activities, using standard in vitro and in vivo models. NPW exhibited inhibition of nitrogen radical generation in LPS-activated macrophages (IC₅₀ = 75.5 μg/mL) through suppression of iNOS protein, with no associated toxicity in the cells. Further, 500 mg/kg of NPW reduced rat paw edema by ∼50% after 6 h of carrageenan administration. Hepatoprotective activity of NPW was also evaluated in vivo on CCl4-induced hepatotoxicity model in rats. NPW treatment (500 mg/kg/day for ten days) attenuated CCl4-induced increase in serum enzymes, viz. alanine and aspartate aminotransferases (ALT and AST) and bilirubin. Also, glutathione and superoxide dismutase (SOD)-levels were restored towards normalcy in the liver of CCl4-treated rats, indicating the hepatoprotective role of NPW, which was found to contain a fair amount of flavonoids, phenolics, and saponin constituents.     

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.     

A validated bioanalytical method in mouse,rat, rabbit and human plasma for the quantification of one of the steroid glycosides found in Hoodia gordonii extract

Hoodia gordonii extract contains steroid glycosides, fatty acids, plant sterols and polar organic material. Certain steroid glycosides show appetite suppressant activities following oral ingestion. This study describes the validation of a bioanalytical method for the quantification of one of the steroid glycosides, H.g.-12 (～10% (w/w) of the extract), in mouse, rat, rabbit and human plasma. The method utilises a liquid–liquid extraction with methyl-tert-butyl ether followed by chromatographic separation on a 2.1 × 50 mm C₁₈ Genesis high performance liquid chromatography (HPLC) column and detection on a triple quadrupole mass spectrometer. Detection of H.g.-12 and its stable isotope internal standards is performed using positive TurboIonspray? ionisation in multiple reaction monitoring mode. The validation procedure demonstrated assay sensitivity, linearity, accuracy, precision and selectivity over the calibration range of 0.5–150 ng/mL in human plasma (500 μL sample volume), 1.0–100 ng/mL in rat and rabbit plasma (150 μL sample volume) and 1.0–250 ng/mL in mouse plasma (150 μL sample volume) with good recoveries (≥77%). H.g.-12 was stable in plasma for ≥6 months at ?20 °C, for up to 4 h at ambient temperature (ca 22 °C) and after 3 freeze–thaw cycles. Plasma extracts were stable for up to 24 h at ambient temperature.     

Paracetamol impairs the profile of amino acids in the rat brain

In our experiment we investigated the effect of subcutaneous administration of paracetamol on the levels of amino acids in the brain structures. Male Wistar rats received for eight weeks paracetamol at two doses: 10 mg/kg b.w. (group P10, n = 9) and 50 mg/kg b.w. per day s.c. (group P50, n = 9).The regional brain concentrations of amino acids were determined in the prefrontal cortex, hippocampus, hypothalamus and striatum of control (Con, n = 9) and paracetamol-treated groups using HPLC. Evaluation of the biochemical results indicated considerable decrease of the content of amino acids in the striatum (glutamine, glutamic acid, taurine, alanine, aspartic acid) and hypothalamus (glycine) between groups treated with paracetamol compared to the control. In the prefrontal cortex paracetamol increased the level of γ-aminobutyric acid (GABA). The present study demonstrated significant effect of the long term paracetamol treatment on the level of amino acids in the striatum, prefrontal cortex and hypothalamus of rats.