Artichoke Leaf Extract Research Articles

LDL-cholesterol-lowering effect of a dietary supplement with plant extracts in subjects with moderate hypercholesterolemia

Red yeast rice (RYR), sugar cane-derived policosanols (SCdP) and artichoke leaf extracts (ALEs) are currently incorporated alone or in combination into dietary supplements for their potential low-density-lipoprotein cholesterol (LDL-cholesterol)-lowering effects. Yet, there is no information supporting the efficacy of this association on the reduction in LDL-cholesterol. The main objective of this study was to investigate the effects of a new dietary supplement (DS) with RYR, SCdP and ALEs on LDL-cholesterol. In a double-blind, randomized, parallel controlled study, 39 subjects from 21 to 55 years with moderate hypercholesterolemia without drug treatment were assigned to 2 groups and then consumed either a DS containing RYR, SCdP and ALEs or a placebo over a 16-week period. Plasma concentrations of lipids [LDL-cholesterol, total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-cholesterol), triacylglycerols (TG)] and plasma levels of vitamins C and E, total polyphenols and malondialdehyde were determined at baseline and after 4, 8, 12 and 16 weeks. LDL-cholesterol and TC were reduced by, respectively, 21.4 % (95 % CI, -13.3 to -24.9 %, p < 0.001) and 14.1 % (95 % CI, -10.1 to -18.0 %, p < 0.001) at week 16 in the DS group compared with baseline. Similar results were obtained at weeks 4, 8 and 12. TG decreased by 12.2 % after 16 weeks in the DS group (95 % CI: -24.4 to -0.1 %, p < 0.05). For the vitamin E/TC ratio, a difference was observed between groups at week 16 (p < 0.05). Other parameters were not modified. Daily consumption of this new DS decreased LDL-cholesterol and TC and is therefore an interesting, convenient aid in managing mild to moderate hypercholesterolemia.

Artichoke Extract Lowered Plasma Cholesterol and Increased Fecal Bile Acids in Golden Syrian Hamsters

A study was conducted in hamsters to determine if artichoke leaf extract (ALE) could lower plasma total and non-HDL cholesterol by increasing fecal excretion of neutral bile acids and sterols. Sixty-four Golden Syrian hamsters (8 week old) were fed control diet or a similar diet containing ALE (4.5 g/kg diet) for 6 weeks. No significant changes for total cholesterol, HDL, non-HDL cholesterol triglycerides or fecal neutral sterols and bile acids were found after 21 days for ALE-fed animals compared with controls. But after 42 days, ALE-fed male hamsters had significantly lower total cholesterol (15%), non-HDL cholesterol (30%) and triglycerides (22%) and female hamsters fed ALE showed reductions of 15% for total cholesterol, 29% for non-HDL cholesterol and 29% for triglycerides compared with controls. Total neutral sterol and bile acids concentrations increased significantly by 50% and 53% in fecal samples of ALE fed males, and 82.4% and 25% in ALE fed females compared with controls. The ALE lowered hamster plasma cholesterol levels by a mechanism involving the greater excretion of fecal bile acids and neutral sterols after feeding for 42 days.

Quantification of Cynaropicrin in Artichoke Leaf Extracts by1H NMR Spectroscopy

The quantification of cynaropicrin in artichoke leaf extracts (ALE) by means of quantitative ¹H NMR was performed. The method relies on solid phase extraction for sample preparation and spectra acquisition in DMSO- D₆ containing anthracene as the internal standard. The obtained ¹H NMR spectra revealed excellent signal purity for H-13(b) of cynaropicrin, which was thus chosen for quantification. Validation was performed in terms of selectivity, linearity, precision, accuracy, and robustness. The content of cynaropicrin in the analyzed samples showed considerable variation, ranging from non detectable to 1.6 %. The NMR approach does not rely on external calibration, which represents the major advantage compared to traditional approaches based on HPLC.

Rapid determination of caffeoylquinic acid derivatives in Cynara scolymus L. by ultra‐fast liquid chromatography/tandem mass spectrometry based on a fused core C18 column

An ultra-fast high-performance LC-ESI-MS/MS method was developed for the analysis and quantification of caffeoylquinic acid derivatives, including chlorogenic acid, 1,3-di-O-caffeoylquinic acid (cynarin) and 1,5-di-O-caffeoylquinic acid, in artichoke (Cynara scolymus L.) heads and leaves. The rapid separation (less than 4 min) was achieved based on a Halo fused core C18-silica column (50 mm × 2.1 mm id, 2.7 μm). The target compounds were detected and quantified by a triple-quadrupole mass spectrometer in multiple-reaction monitoring mode. The calibration function is linear from 0.06 to 2800 ng/mL for chlorogenic acid, 0.3-3000 ng/mL for cynarin and 0.24-4800 ng/mL for 1,5-di-O-caffeoylquinic acid, respectively. The average recoveries ranged from 92.1 to 113.2% with RSDs ≤6.5%. Moreover, four batches of artichoke head and leaf extracts were analyzed using the established method. The results indicated that the Halo fused core column provided much faster separations and higher sample throughput without sacrificing column ruggedness and reliability, and triple-quadrupole MS provided extraordinarily lower LOQs for most of the target analytes. Comparing to conventional quantitative approaches, the established method was fast, sensitive and reliable for the determination of caffeoylquinic acid derivatives in artichoke.

Globe artichoke as a functional food

Globe artichoke (Cynara cardunculus var. scolymus L. Fiori) is a traditional component of the Mediterranean diet. Artichoke edible parts are one of the richest dietary sources of polyphenols with high bioavailability, and contain also high-quality inulin, fibres and minerals. Moreover, pharmaceutical artichoke leaf extracts show hypocholesterolemic and choleretic properties. Several clinical studies have shown that the bioactive properties of globe artichoke are due to the high content of polyphenolic compounds in flower heads and leaves, in particular hydroxycinnamates and flavonoids. The total antioxidant capacity of artichoke flower heads is one of the highest reported for vegetables, and is strictly related to their polyphenolic content. Different agronomic variables, such as mycorrhizal inoculation, may affect plant secondary metabolism, and in particular the production of metabolites with health-promoting activities. Our recent data showed large increases of total phenolic content and antioxidant activity in leaves and flower heads of mycorrhizal artichoke plants.

Screening pharmaceutical preparations containing extracts of turmeric rhizome, artichoke leaf, devil's claw root and garlic or salmon oil for antioxidant capacity.

Pharmaceutical preparations derived from natural sources such as vegetables often contain compounds that contribute to the antioxidant defence system and apparently play a role in the protection against degenerative diseases. In the present study, commercial preparations containing extracts of turmeric, artichoke, devil's claw and garlic or salmon oil were investigated. The products were divided into fractions of different polarity, and their antioxidant activity was determined using the Trolox equivalent antioxidant capacity (TEAC) assay. This test is based on the efficacy of the test material to scavenge 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) derived radicals. Total phenols were determined in all fractions as well as specific carotenoids in the most lipophilic fraction to assess their contribution to the antioxidant activity. For comparison, the radical scavenging effect of selected constituents of the extracts such as curcumin, luteolin, kaempferol, chlorogenic acid, harpagoside, beta-carotene and alpha-tocopherol was investigated and compared with that of Trolox. Curcumin, luteolin, kaempferol, chlorogenic acid and beta-carotene showed an antioxidant activity superior to Trolox in the TEAC assay; harpagoside was barely active. All fractions of the turmeric extract preparation exhibited pronounced antioxidant activity, which was assigned to the presence of curcumin and other polyphenols. The antioxidant activity corresponding to the artichoke leaf extract was higher in the aqueous fractions than in the lipophilic fractions. Similarly, devil's claw extract was particularly rich in water-soluble antioxidants. Harpagoside, a major compound in devil's claw, did not contribute significantly to its antioxidant activity. The antioxidant capacity of the garlic preparation was poor in the TEAC assay. That of salmon oil was mainly attributed to vitamin E, which is added to the product for stabilization. In all test preparations, the antioxidant activity was significantly correlated with the content of total phenolic compounds.

Effects of Artichoke Leaf Extract on Acute Gastric Mucosal Injury in Rats

The present study was designed to clarify the effects of an ethanol extract of artichoke leaf on acute gastric mucosal injury in rats. Oral administration of artichoke leaf extract dose-dependently prevented absolute ethanol-induced (125-500 mg/kg) or restraint plus water immersion stress-induced gastric mucosal injury (1000-2000 mg/kg). The artichoke leaf extract contains 1% cynaropicrin and 0.8% chlorogenic acid as main components and 70% dextrin as a vehicle. Cynaropicrin at doses of 1/100 of artichoke leaf extract [ethanol-induced mucosal injury: 5 mg/kg, per os (p.o.); stress-induced mucosal injury: 20 mg/kg, p.o.] also prevented gastric mucosal injury in both animal models. However, dextrin and chlorogenic acid at doses contained in the leaf extract were ineffective in both models. When artichoke leaf extract was given orally to normal rats, it (500-2000 mg/kg, p.o.) dose-dependently increased gastric mucus content. In addition, it (125-500 mg/kg, p.o.) dose-dependently prevented the decrease in gastric mucus content by absolute ethanol. When the effects of artichoke leaf extract on basal gastric acid secretion in rats were evaluated, it (500-2000 mg/kg, p.o.) dose-dependently increased the volume of gastric juice in normal rats. However, it was ineffective in decreasing basal gastric acid secretion in normal rats. These results indicate that artichoke leaf extract is effective against acute gastritis and its beneficial effect is due to that of cynaropicrin. The gastric mucus-increasing action of artichoke leaf extract may be, at least in part, related to the anti-gastritic action of the extract.

Artichoke leaf extract reduces oxidative stress and lipoprotein dyshomeostasis in rats fed on high cholesterol diet

Hypercholesterolemia and lipid peroxidation play complementary role in atherosclerosis. Artichoke leaf extract (ALE) is rich in natural antioxidants and has a cholesterol-reducing effect. However, there is no study investigating the effect of ALE on lipid levels and lipid peroxidation in experimental hypercholesterolemic conditions. Rats were fed on 4% (w/w) cholesterol and 1% (w/w) cholic acid supplemented diet for 1 month. ALE (1.5 g/kg/day) was given by gavage during the last 2 weeks. Serum lipid composition, malondialdehyde (MDA) and diene conjugate (DC) levels and plasma antioxidant activity (AOA) were measured. In addition, endogenous DC and copper-induced MDA levels were determined in apo B-containing lipoproteins (LDL+VLDL fraction). Serum cholesterol and triglyceride levels and the ratio of cholesterol to HDL-cholesterol decreased due to ALE treatment in rats fed on HC diet. Significant decreases in serum MDA and DC levels and increases in plasma AOA were detected in serum in ALE-treated hypercholesterolemic rats. Endogenous DC and copper-induced MDA levels were also lower in LDL+VLDL fraction due to ALE-treatment in hypercholesterolemic rats. Our results indicate that ALE may be useful for the prevention of hypercholesterolemia-induced pro-oxidant state in LDL+VLDL fraction and the reduction of increased serum cholesterol and triglyceride levels.

Effect of Artichoke Leaf Extract on Hepatic and Cardiac Oxidative Stress in Rats Fed on High Cholesterol Diet

Hypercholesterolemia and lipid peroxidation play complementary roles in atherosclerosis. Artichoke (Cynara scolymus L., Asteraceae) leaf extract (ALE), rich in antioxidants, has cholesterol-reducing effect. We investigated the effect of ALE on serum and hepatic lipid levels and pro-oxidant-antioxidant balance in the liver and heart of hypercholesterolemic rats. Rats were fed on 4% (w/w) cholesterol and 1% cholic acid (w/w) supplemented diet for 1 month. ALE (1.5 g/kg/day) was given by gavage during the last 2 weeks. High cholesterol (HC) diet caused significant increases in serum and liver cholesterol and triglyceride levels. It increased malondialdehyde (MDA) and diene conjugate (DC) levels in both tissues. Hepatic vitamin E levels and hepatic and cardiac glutathione peroxidase (GSH-Px) activities decreased, but superoxide dismutase and glutathione transferase activities, glutathione, and vitamin C levels remained unchanged due to HC diet. Serum cholesterol and triglyceride levels and ratio of cholesterol to high-density lipoprotein (HDL)-cholesterol decreased in ALE plus HC-treated rats, but liver cholesterol and triglyceride levels remained unchanged. Significant decreases in hepatic and cardiac MDA and DC levels and increases in hepatic vitamin E and GSH-Px activities were observed in ALE-treated hypercholesterolemic rats. Our results indicate that ALE decreases serum lipids and hypercholesterolemia-induced pro-oxidant state in both tissues.

In vitro investigations of Cynara scolymus L. extract on cell physiology of HepG2 liver cells

The objective of this study was the investigation of a potential influence of artichoke leaf extract (ALE) on the cell physiology and gene expression of phase I/II enzymes of human liver cells HepG2 and investigation on potential cell protective effects against ethanol-induced cell toxicity against HepG2 cells. Cell biological assays under in vitro conditions using HepG2 liver cells and investigation of mitochondrial activity (MTT test), proliferation assay (BrdU incorporation ELISA), LDH as toxicity marker, gene expression analysis by RT-PCR and enzyme activity of glutationtransferase. Artichocke extract, containing 27% caffeoylquinic acids and 7% flavonoids induced mitochondrial activity, proliferation and total protein content under in vitro conditions in human liver cells HepG2. These effects could not be correlated to the well-known artichoke secondary compounds cynarin, caffeic acid, chlorogenic acid, luteolin and luteolin-7-O-glucoside. The flavones luteolin and luteolin-7-O-glucoside had inhibitory effects at 100 µg/mL level on HepG2 cells, with luteolin being a significant stronger inhibitor compared to the respective glucoside. Artichoke leaf extract had minor stimulating effect on gene expression of CYP1A2, while CYP3A4, GGT, GPX2, GSR and GST were slightly inhibited. GST inhibition under in vitro conditions was also shown by quantification of GST enzyme activity. Induction of gene expression of CYP1A2 was shown to be supraadditive after simultaneous application of ethanol plus artichoke extract. Artichoke leaf extract exhibited cell protective effects against ethanol-induced toxicity within cotreatment under in vitro conditions. Also H2O2 damage was significantly inhibited by simultaneous artichoke incubation. Pre- and posttreatments did not exert protective effects. DMSO-induced toxicity was significantly reduced by pre-, post- and cotreatment with artichoke extract and especially with luteolin-7-O-glucoside, indicating a direct interaction with the toxifying agent and an induction of repair mechanisms.

Globe artichoke: A functional food and source of nutraceutical ingredients

Globe artichoke ( Cynara cardunculus L. subsp. scolymus (L.) Hayek, (formerly Cynara scolymus L.) represents an important component of the Mediterranean diet, and is a rich source of bioactive phenolic compounds, and also inulin, fibre and minerals. In addition, artichoke leaf extracts have long been used in folk medicine, particularly for liver complaints. These therapeutic properties have been often been ascribed to the cynarin (1,3- O-dicaffeoylquinic acid) content of these extracts. In various pharmacological test systems, artichoke leaf extracts have exhibited hepatoprotective, anticarcinogenic, antioxidative, antibacterial, anti-HIV, bile-expelling, and urinative activities as well as the ability to inhibit cholesterol biosynthesis and LDL oxidation. These broad therapeutic indications cannot be ascribed to a single, but to several active compounds that together generate additive or synergistic pharmacologic effects; these include mono- and dicaffeoylquinic acids, and flavonoids such as luteolin and its 7- O-glucoside. Artichoke by-products such as leaves, external bracts and stems that are produced by the artichoke processing industry, represent a huge amount of discarded material (about 80–85% of the total biomass of the plant), which could be used as a source of inulin but also of phenolics, and should be considered as a raw material for the production of food additives and nutraceuticals.

Natural sources of antidyslipidaemic agents: is there an evidence-based approach for their prescription?

Numerous randomized clinical trials, systematic reviews and meta-analyses have confirmed the antidyslipidaemic activity of different dietary supplements, nutraceuticals and herbal remedies. International guidelines for cardiovascular disease prevention have begun to consider dietary supplements as an evidence-based approach to improve patients’ plasma lipid levels. They already suggest to increasing or supplementing the dietary intake of soluble fibre (especially psyllium), soy proteins, plant sterols, niacin, and fish oil. Among the nutraceuticals, mevacoline and policosanol are both able to reduce plasma LDL-C by a mean of 20%. A preliminary clinical study of berberine has shown it to be the most powerful antihyperlipidaemic natural compound, reducing plasma LDL-C by 25% and triglycerides by 35%. Among the herbal remedies, several placebo-controlled randomized clinical trials have confirmed the anti-Numerous randomized clinical trials, systematic reviews and meta-analyses have confirmed the antidyslipidaemic activity of different dietary supplements, nutraceuticals and herbal remedies. International guidelines for cardiovascular disease prevention have begun to consider dietary supplements as an evidence-based approach to improve patients’ plasma lipid levels. They already suggest to increasing or supplementing the dietary intake of soluble fibre (especially psyllium), soy proteins, plant sterols, niacin, and fish oil. Among the nutraceuticals, mevacoline and policosanol are both able to reduce plasma LDL-C by a mean of 20%. A preliminary clinical study of berberine has shown it to be the most powerful antihyperlipidaemic natural compound, reducing plasma LDL-C by 25% and triglycerides by 35%. Among the herbal remedies, several placebo-controlled randomized clinical trials have confirmed the antihypercholesterolaemic, and antihypertriglyceridaemic properties of aged garlic powder, artichoke leaf extracts, guggul, and fenugreek. Single small clinical trials have also suggested that Korean ginseng, green tea, onion, yarrow, holy basil and arjun have an antihypercholesterolaemic effect.

Phytochemical characterization of artichoke leaf extract and assessment of its protective effects from alcohol and chemically-induced damage in human liver cells

Purpose: As the use of herbal extracts to alleviate common ailments continues to increase, the demand for liver detoxifying products is also increasing. Artichoke, Cynara scolymus L. is a member of the Asteraceae/Compositae family. The study objective was to characterize the phytochemical components of artichoke leaf extract (ALE) and assess its hepato-protective property against alcohol and chemically induced liver damage. Methods: ALE was manufactured from dry leaves using ethanol/water (60:40), pre-incubated for 24hrs at 20–25oC. The herb extract ratio was 5–7:1. Human liver cells were pre-treated with ALE and either an alcohol or a carbon tetrachloride (CCl4) insult. The hepato-protective property of the sample was measured using cell viability assays. Samples were tested at various concentrations and estimation of the EC50 determined. The ability of ALE to induce Phase II enzyme was assessed. Qualitative and quantitative analytical methods using High Performance Liquid Chromatography (HPLC) were developed and validated for the phytochemical fingerprint characterization of ALE. Results: Bio-assay studies of ALE show a dose-dependent protection of the cells from alcohol damage with an EC50&lt;1µg/ml, showing a 90% protection of the cells at 1µg/ml compared to control. No protection of the cells from CCl4-induced damage was observed. ALE was shown to be a potent inducer of Phase II enzymes. Analysis of the extract shows the presence of phytochemicals having caffeoyl quinic acid moiety (chlorogenic acid, cynarin and related compounds). Conclusions: ALE standardized to chlorogenic acid presents a good herbal alternative for liver protection against insults from alcohol.

Effect of pretreatment with artichoke extract on carbon tetrachloride-induced liver injury and oxidative stress

Artichoke is a plant with antioxidant properties. In this study, we investigated the effect of artichoke extract pretreatment on carbon tetrachloride (CCl 4)-induced oxidative stress and hepatotoxicity. Rats were given artichoke leaf extract (1.5 g/kg/day) by gavage for 2 weeks and after then CCl 4 (1 ml/kg; i.p.) was applied. All rats were killed 24 h after the CCl 4 injection. CCl 4 administration resulted in hepatic necrosis and significant increases in plasma transaminase activities as well as hepatic malondialdehyde (MDA) and diene conjugate (DC) levels in the liver of rats. Glutathione (GSH) and vitamin C levels decreased, but vitamin E levels increased in the liver of CCl 4-treated rats. Hepatic superoxide dismutase (SOD) activities remained unchanged, but glutathione peroxidase (GSH-Px) and glutathione transferase (GST) activities decreased following CCl 4 treatment. In rats pretreated with artichoke extract, significant decreases in plasma transaminase activities and amelioration in histopathological changes in the liver were observed following CCl 4 treatment as compared to CCl 4-treated rats. In addition, hepatic MDA and DC levels decreased, but GSH levels and GSH-Px activities increased without any change in other antioxidant parameters following CCl 4 treatment in artichoke-pretreated rats. The present findings indicate that in vivo architoke extract administration may be useful for the prevention of oxidative stress-induced hepatotoxicity.

Artichoke leaf extract (Cynara scolymus) reduces plasma cholesterol in otherwise healthy hypercholesterolemic adults: A randomized, double blind placebo controlled trial

Cardiovascular diseases are the chief causes of death in the UK, and are associated with high circulating levels of total cholesterol in the plasma. Artichoke leaf extracts (ALEs) have been reported to reduce plasma lipids levels, including total cholesterol, although high quality data is lacking. The objective of this trial was to assess the effect of ALE on plasma lipid levels and general well-being in otherwise healthy adults with mild to moderate hypercholesterolemia. 131 adults were screened for total plasma cholesterol in the range 6.0-8.0 mmol/l, with 75 suitable volunteers randomised onto the trial. Volunteers consumed 1280 mg of a standardised ALE, or matched placebo, daily for 12 weeks. Plasma total cholesterol decreased in the treatment group by an average of 4.2% (from 7.16 (SD 0.62) mmol/l to 6.86 (SD 0.68) mmol/l) and increased in the control group by an average of 1.9% (6.90 (SD 0.49) mmol/l to 7.03 (0.61) mmol/l), the difference between groups being statistically significant (p=0.025). No significant differences between groups were observed for LDL cholesterol, HDL cholesterol or triglyceride levels. General well-being improved significantly in both the treatment (11%) and control groups (9%) with no significant differences between groups. In conclusion, ALE consumption resulted in a modest but favourable statistically significant difference in total cholesterol after 12 weeks. In comparison with a previous trial, it is suggested that the apparent positive health status of the study population may have contributed to the modesty of the observed response.

Flavonoids of Cynara scolymus Possess Potent Xanthinoxidase Inhibitory Activity in vitro but are Devoid of Hypouricemic Effects in Rats after Oral Application

Artichoke (Cynara scolymus L.) leaves have been historically used for the treatment of hyperuricemia and gout, however whether artichoke is truly efficacious for this indication, is still a matter of debate. Thus, the goal of the present study was first to examine the xanthine oxidase (XO) inhibitory activity of an artichoke leaf extract (ALE) and some of its main compounds in vitro and then further test potentially active substances for possible hypouricemic effects using an in vivo rat model. The in vitro study showed that ALE inhibited XO with only minimal inhibitory action (< 5 %) at 100 microg/mL. However, when selected compounds were tested, the caffeic acid derivatives revealed a weak XO inhibitory effect with IC (50) > 100 microM. From the tested flavones the aglycone luteolin potently inhibited XO with an IC (50) value of 1.49 microM. Luteolin 7-O-glucoside and luteolin 7-O-glucuronide showed lower XO inhibition activities with IC (50) values of 19.90 microM and 20.24 microM, respectively. However, oral administration of an aqueous ALE, luteolin, and luteolin 7-O-glucoside did not produce any observable hypouricemic effects after acute oral treatment in potassium oxonate-treated rats. After intraperitoneal injection of luteolin a decrease in uric acid levels was detected suggesting that the hypouricemic effects of luteolin are due to its original form rather than its metabolites produced by the gut flora. In conclusion, an aqueous ALE, caffeic acid derivatives and flavones exerted XO inhibitory effects in vitro but a hypouricemic activity could not be confirmed after oral administration.

Clinical uses of artichoke leaf extract

Artichoke, or Cynara scolymus , is a native plant to southern Europe, northern Africa, and the Canary Islands.[1][1]–[4][2] Artichoke is a member of the Asteraceae, or daisy, family and is thought to be one of the oldest used medicinal plants. It has been pictured in ancient Egyptian drawings and

Bioavailability and pharmacokinetics of caffeoylquinic acids and flavonoids after oral administration of Artichoke leaf extracts in humans

Extracts from artichoke leaves are traditionally used in the treatment of dyspeptic and hepatic disorders. Various potential pharmacodynamic effects have been observed in vitro for mono- and dicaffeoylquinic acids (e.g. chlorogenic acid, cynarin), caffeic acid and flavonoids (e.g. luteolin-7-O-glucoside) which are the main phenolic constituents of artichoke leaf extract (ALE). However, in vivo not only the genuine extract constituents but also their metabolites may contribute to efficacy. Therefore, the evaluation of systemic availability of potential bioactive plant constituents is a major prerequisite for the interpretation of in vitro pharmacological testing. In order to get more detailed information about absorption, metabolism and disposition of ALE, two different extracts were administered to 14 healthy volunteers in a crossover study. Each subject received doses of both extracts. Extract A administered dose: caffeoylquinic acids equivalent to 107.0 mg caffeic acid and luteolin glycosides equivalent to 14.4 mg luteolin. Extract B administered dose: caffeoylquinic acids equivalent to 153.8 mg caffeic acid and luteolin glycosides equivalent to 35.2 mg luteolin. Urine and plasma analysis were performed by a validated HPLC method using 12-channel coulometric array detection. In human plasma or urine none of the genuine target extract constituents could be detected. However, caffeic acid (CA), its methylated derivates ferulic acid (FA) and isoferulic acid (IFA) and the hydrogenation products dihydrocaffeic acid (DHCA) and dihydroferulic acid (DHFA) were identified as metabolites derived from caffeoylquinic acids. Except of DHFA all of these compounds were present as sulfates or glucuronides. Peak plasma concentrations of total CA, FA and IFA were reached within 1 h and declined over 24 h showing almost biphasic profiles. In contrast maximum concentrations for total DHCA and DHFA were observed only after 6-7 h, indicating two different metabolic pathways for caffeoylquinic acids. Luteolin administered as glucoside was recovered from plasma and urine only as sulfate or glucuronide but neither in form of genuine glucosides nor as free luteolin. Peak plasma concentrations were reached rapidly within 0.5 h. The elimination showed a biphasic profile.

Phenolic Compounds from the Leaf Extract of Artichoke (Cynara scolymus L.) and Their Antimicrobial Activities

A preliminary antimicrobial disk assay of chloroform, ethyl acetate, and n-butanol extracts of artichoke (Cynara scolymus L.) leaf extracts showed that the n-butanol fraction exhibited the most significant antimicrobial activities against seven bacteria species, four yeasts, and four molds. Eight phenolic compounds were isolated from the n-butanol soluble fraction of artichoke leaf extracts. On the basis of high-performance liquid chromatography/electrospray ionization mass spectrometry, tandem mass spectrometry, and nuclear magnetic resonance techniques, the structures of the isolated compounds were determined as the four caffeoylquinic acid derivatives, chlorogenic acid (1), cynarin (2), 3,5-di-O-caffeoylquinic acid (3), and 4,5-di-O-caffeoylquinic acid (4), and the four flavonoids, luteolin-7-rutinoside (5), cynaroside (6), apigenin-7-rutinoside (7), and apigenin-7-O-beta-D-glucopyranoside (8), respectively. The isolated compounds were examined for their antimicrobial activities on the above microorganisms, indicating that all eight phenolic compounds showed activity against most of the tested organisms. Among them, chlorogenic acid, cynarin, luteolin-7-rutinoside, and cynaroside exhibited a relatively higher activity than other compounds; in addition, they were more effective against fungi than bacteria. The minimum inhibitory concentrations of these compounds were between 50 and 200 microg/mL.

Artichoke leaf extract reduces symptoms of irritable bowel syndrome and improves quality of life in otherwise healthy volunteers suffering from concomitant dyspepsia: a subset analysis.

Does artichoke leaf extract (ALE) ameliorate symptoms of Irritable bowel syndrome (IBS) in otherwise healthy volunteers suffering concomitant dyspepsia? A subset analysis of a previous dose-ranging, open, postal study, in adults suffering dyspepsia. Two hundred and eight (208) adults were identified post hoc as suffering with IBS. IBS incidence, self-reported usual bowel pattern, and the Nepean Dyspepsia Index (NDI) were compared before and after a 2-month intervention period. There was a significant fall in IBS incidence of 26.4% (p < 0.001) after treatment. A significant shift in self-reported usual bowel pattern away from "alternating constipation/diarrhea" toward "normal" (p < 0.001) was observed. NDI total symptom score significantly decreased by 41% (p < 0.001) after treatment. Similarly, there was a significant 20% improvement in the NDI total quality-of-life (QOL) score in the subset after treatment. This report supports previous findings that ALE ameliorates symptoms of IBS, plus improves health-related QOL.