Comparative analysis of fecal phenolic content between normal and obese rats after oral administration of tea polyphenols.

Tea polyphenols (TP) have many health benefits, but most are metabolized into low molecular-weight phenolic acids after oral administration. In the present study, the absorption, metabolism, and excretion of catechins in rats fed a normal chow diet and in obese rats fed a high-fat and high-sugar (HFHS) diet were compared. After a ten-day oral administration of TP (500 mg per kg bw), the plasma levels of (-)-epigallocatechin gallate (EGCG) and (-)-gallocatechin gallate (GCG) in obese rats were significantly lower than those in the normal group. In obese rats, the fecal levels of EGCG, (-)-epicatechin gallate (ECG) and GCG were significantly enhanced. Ten phenolic metabolites of TP were quantitatively analyzed, and the results showed that 4-hydroxyphenylacetic acid was the primary metabolite in feces and plasma. The plasma and fecal concentrations of 4-hydroxyphenylacetic acid in the obese group were significantly lower than those in normal rats, but the levels of 4-hydroxyphenylpropionic acid in plasma and feces were increased. The content of other phenolic acids was also dramatically changed. These results suggested that a HFHS diet might influence the excretion of tea catechins, leading to insufficient metabolism of catechins by the gut microflora.

NIR Spectroscopy of Actaea racemosa L. rhizome - En Route to Fast and Low-Cost Quality Assessment.

Rhizomes of Actaea racemosa L. (formerly Cimicifuga racemosa) gained increasing interest as a plant-derived drug due to its hormone-like activity and the absence of estrogenic activity. According to the Current Good Manufacturing Practices guidelines and pharmacopeial standards, quality assessment of herbal starting materials includes tests on identity and substitution, as well as quantification of secondary metabolites, usually by HPTLC and LC methods. To reduce the laboratory effort, we investigated near-infrared spectroscopy for rapid species authentication and quantification of metabolites of interest.Near-infrared spectroscopy analysis is carried out directly on the milled raw plant material. Spectra were correlated with reference data of polyphenols and triterpene glycosides determined by LC/diode array detection and LC/evaporative light scattering detection, respectively. Quantification models were built and validated by cross-validation procedures. Clone plants, derived by vegetative propagation, and plants of a collection from different geographical origins cultivated in Berlin were analysed together with mixed batches from wild harvests purchased at wholesalers.Generally, good to excellent correlations were found for the overall content of polyphenols with coefficients of determination of R2 > 0.93. For individual polyphenols such as fukinolic acid, only models containing clone plants succeeded (R2 > 0.92). For the total content of triterpene glycosides, results were generally worse in comparison to polyphenols and were observed only for the mixed batches (R2 = 0.93).Next to quantitative analysis, near-infrared spectroscopy was proven as a rapid alternative to other, more laborious methods for species authentication. Near-infrared spectroscopy was able to distinguish different Actaea spp. such as the North American Actaea cordifolia and the Asian Actaea cimicifuga, Actaea dahurica, Actaea heracleifolia, and Actaea simplex.

Leaching of the Neonicotinoids Thiamethoxam and Imidacloprid from Sugar Beet Seed Dressings to Subsurface Tile Drains.

Pesticide transport from seed dressings toward subsurface tile drains is still poorly understood. We monitored the neonicotinoid insecticides imidacloprid and thiamethoxam from sugar beet seed dressings in flow-proportional drainage water samples, together with spray applications of bromide and the herbicide S-metolachlor in spring and the fungicides epoxiconazole and kresoxim-methyl in summer. Event-driven, high first concentration maxima up to 2830 and 1290 ng/L for thiamethoxam and imidacloprid, respectively, were followed by an extended period of tailing and suggested preferential flow. Nevertheless, mass recoveries declined in agreement with the degradation and sorption properties collated in the groundwater ubiquity score, following the order bromide (4.9%), thiamethoxam (1.2%), imidacloprid (0.48%), kresoxim-methyl acid (0.17%), S-metolachlor (0.032%), epoxiconazole (0.013%), and kresoxim-methyl (0.003%), and indicated increased leaching from seed dressings compared to spray applications. Measured concentrations and mass recoveries indicate that subsurface tile drains contribute to surface water contamination with neonicotinoids from seed dressings.

Dissipation behavior of hexaconazole and kresoxim-methyl residues in ginseng and soil under field conditions.

The dissipation and terminal residues of a fungicide suspension (5% hexaconazole, 25% kresoxim-methyl) in ginseng and soil were investigated by high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). At fortified levels of 0.01, 0.02, and 0.20 mg kg(-1), the recoveries of hexaconazole and kresoxim-methyl were in the range of 80.6∼94.8% and 82.4∼98.8% with relative standard deviation of 3.42-9.12% and 3.19-8.58%, respectively. The half-lives were 7.09-10.73 days in root, 6.80-7.95 days in stem, 5.31-8.49 days in leaf, and 6.30-7.97 days in soil. The terminal residues were all below the maximum residue limits (MRLs) of EU and South Korea. Risk assessment results indicated that the risk of hexaconazole and kresoxim-methyl use in ginseng at dosage of 60-90 g a.i. ha(-1) was negligible to humans. This work would help the government to establish the MRL and provide guidance on the proper and safe use of hexaconazole and kresoxim-methyl in ginseng.

Separation and characterization of soluble esterified and glycoside-bound phenolic compounds in dry-blanched peanut skins by liquid chromatography-electrospray ionization mass spectrometry.

A large variety of soluble phenolic compounds, including phenolic acids (hydroxybenzoic acids, ethyl protocatechuate, and hydroxycinnamic acids, as well as phenylacetic acid and phenyllactic acid), stilbenes (trans-piceatannol and trans-3,3',5,5'-tetrahydroxy-4'-methoxystilbene), flavan-3-ols (e.g., (-)-epicatechin, (+)-catechin, (-)-epiafzelechin, and their polymers (the proanthocyanidins, PACs)), other flavonoids (e.g., isoflavones, flavanols, and flavones), and biflavonoids, were released from esters and glycosides by base/acid hydrolysis and identified in acetonic extracts of dry-blanched peanut skins (PS). Reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with electrospray ionization mass spectrometry (ESI-MS(n)) was applied to separate and identify the phenolic constituents. Tentative identification of the separated phenolics was based on molecular ions and MS(n) fragmentation patterns acquired by ESI-MS in the negative-ion mode. Identification of free phenolic acids, stilbenes, and flavonoids was also achieved by commercial standards and by published literature data. Quantification was performed on the basis of peak areas of the UV signals from the HPLC chromatograms and calibration curves of the commercial standards. The flavonoids of PS exist mostly in glycoside-bound forms, but the aglycones can be liberated upon acid hydrolysis. PS contain significantly more PACs compared to free phenolic compounds: PAC monomers to tetramers constituted 92.0% of esterified phenolic compounds. The PAC monomer ((+)-catechin) and dimers are the main phenolics released from glycosides and account for 31.7 and 59.1%, respectively, of the total glycoside-bound phenolic compounds.

Microbial catabolism of procyanidins by human gut microbiota.

SCOPE: A major portion of ingested procyanidins is degraded by human microbiota in the colon into various phenolic compounds. These microbial metabolites are thought to contribute to the health benefits of procyanidins in vivo. The objective of this study was to identify and quantify the microbial metabolites of procyanidins after anaerobic fermentation with human microbiota. METHODS AND RESULTS: (-)-Epicatechin, (+)-catechin, procyanidin B2, procyanidin A2, partially purified apple and cranberry procyanidins were incubated with human microbiota at a concentration equivalent to 0.5 mM epicatechin. GC-MS analysis showed that common metabolites of all six substrates were benzoic acid, 2-phenylacetic acid, 3-phenylpropionic acid, 2-(3'-hydroxyphenyl)acetic acid, 2-(4'-hydroxyphenyl)acetic acid, 3-(3'-hydroxyphenyl)propionic acid, and hydroxyphenylvaleric acid. 5-(3',4'-Dihydroxyphenyl)-γ-valerolactones and 5-(3'-hydroxyphenyl)-γ-valerolactones were identified as the microbial metabolites of epicatechin, catechin, procyanidin B2, and apple procyanidins but not from the procyanidin A2 or cranberry procyanidin ferments. 2-(3',4'-Dihydroxyphenyl)acetic acid was only found in the fermented broth of procyanidin B2, A2, apple, and cranberry procyanidins. The mass recoveries of microbial metabolites range from 20.0 to 56.9% for the six substrates after 24 h of fermentation. CONCLUSION: Procyanidins, both B-type and A-type can be degraded by human gut microbiota. The microbial metabolites may contribute to the bioactivities of procyanidins.

[Determination of seven strobilurin fungicide residues in Chinese herbs by liquid chromatography-tandem mass spectrometry coupled with solid phase extraction].

An LC-MS/MS method was developed for the simultaneously determination of seven strobilurin fungicide residues in Chinese herbs. The strobilurin fungicides include Z-metominostrobin, kresoxim-methyl, dimoxystrobin, picoxystrobin, pyraclostrobin, azoxystrobin and trifloxystrobin. The sample was extracted with ethyl acetate and cleaned-up by an amino SPE column. The seven strobilurin fungicide residues were separated on a C18 column with gradient elution of 1.0 per thousand formic acid and methanol as mobile phases, and detected by ESI-MS in positive ion and selective reaction monitoring (SRM) mode. External standard method was used to the quantification with good linear relationships (r > or = 0. 996). The LOQs were 2 micro g/kg for dimoxystrobin, picoxystrobin and trifloxystrobin, 4 mciro g/kg for pyraclostrobin and azoxystrobin, 10 micro g/kg for Z-metominostrobin and kresoxim-methyl. The recoveries were from 60.4% to 110% with the RSDs between 1.2% and 17%. The developed method is suitable for the determination and confirmation of the seven strobilurin fungicide residues in the three of Eight Zhes ( Ophiopogon japonicus (Thunb.), Scrophularia ningpoensis Hemsl. and Corydalis yanhusuo W T Wang).

Coordination polymer adsorbent for matrix solid-phase dispersion extraction of pesticides during analysis of dehydrated Hyptis pectinata medicinal plant by GC/MS.

The coordination polymer [Zn(BDC)(H(2)O)(2)](n) was tested for extraction of pyrimethanil, ametryn, dichlofluanid, tetraconazole, flumetralin, kresoxim-methyl and tebuconazole from the medicinal plant Hyptis pectinata, with analysis using gas chromatography-mass spectrometry in selected ion monitoring mode (GC/MS, SIM). Experiments carried out at different fortification levels (0.1, 0.5 and 1.0 µg g(-1)) resulted in recoveries in the range 73-97%, and RSD values were between 5 and 12% for the [Zn(BDC)(H(2)O)(2)](n) sorbent. Detection and quantification limits ranged from 0.02 to 0.07 µg g(-1) and from 0.05 to 0.1 µg g(-1), respectively, for the different pesticides studied. The method developed was linear over the range tested (0.04-14.0 µg g(-1)), with correlation coefficients ranging from 0.9987 to 0.9998. Comparison between [Zn(BDC)(H(2)O)(2)](n) and the commercial phase C(18)-bonded silica showed good performance of the [Zn(BDC)(H(2)O)(2)](n) polymeric sorbent for the pesticides tested.

Phenylacetic acids were detected in the plasma and urine of rats administered with low-dose mulberry leaf extract.

The use of a high quercetin dose to demonstrate its absorption and bioavailability does not reflect the real dietary situation because quercetin glycosides are usually present in small amounts in the human diet. This study aimed to demonstrate the absorption and bioavailability of quercetin in mulberry leaves that represents a more physiologic dietary situation. Mulberry leaf ethanol extract was prepared similar to tea infusion, which is the way the tea leaves are generally prepared for consumption. Accordingly, rats were fed by oral intubation the mulberry leaf ethanol extract (15 g%/rat per day) or pure rutin (135 microg/rat per day) for 2 weeks. The control group received a similar volume of the vehicle, 10% ethanol. There was a significant increase in total antioxidant activity (TAA) in the urine and feces of the antioxidants-fed rats. Phenylacetic acid, a microbial metabolite of quercetin, was detected in the urine of the test animals, and quercetin was present in the fecal samples. By using an in situ intestinal preparation, 3-hydroxyphenylacetic acid, another microbial metabolite of quercetin, was detected in the plasma when the duodenal segment was instilled with 2 mg of rutin. This microbial metabolite retained 50% of the TAA of quercetin. The results of this study indicate that in a more realistic dietary situation, an increase in TAA in the body after consumption of quercetin-containing foods is contributed mainly by the microbial metabolites.

Identification of flavonoid metabolites after oral administration to rats of a Ginkgo biloba extract.

An extract of Ginkgo biloba leaves (EGb) was administered by gastric probe to Wistar female rats, and urine and faeces samples were collected for 5 days and whole blood samples were withdrawn every 30 min for 6 h. After purification with SPE C18 cartridges, the samples were analysed by reversed-phase LC-diode array detection (LC-DAD) for residual flavonoid glycosides, aglycones and metabolites. No glycosides or aglycones were detected in urine, faeces or blood and extensive degradation of EGb flavonoids within 24 h was detected. Among the seven different phenylalkyl acids detected by LC-DAD, 3,4-dihydroxyphenylacetic acid (I), hippuric acid (II), 3-hydroxyphenylacetic acid (III), homovanillic acid (IV) and benzoic acid (VII) were directly confirmed by on-line mass spectrometry using an electrospray interface (ES-MS). Peaks V and VI needed to be collected and separately examined and they were found to be 3-(4-hydrophenyl)propionic acid and 3-(3-hydrophenyl)propionic acid, respectively. As further evidence, the identity of metabolites I, II, III, IV, V and VII was confirmed by co-chromatography with authentic standards.

Cow's urine concoction: its chemical composition, pharmacological actions and mode of lethality.

A review of current information on the composition, pharmacological actions and mode of death from cow's urine concoction (CUC) toxicity is presented. The concoction is prepared from leaves of tobacco, garlic and basil; lemon juice, rock salt and bulbs of onion. The latter items are soaked in the urine from cows which acts as the vehicle in which the active principles in these constituents dissolve. Over fifty chemical compounds have been identified in CUC. The major compounds it contains are benzoic acid, phenylacetic acid, p-cresol, thymol and nicotine. The chemical composition and pharmacological cations of the individual components of CUC are also reviewed. Observations of CUC poisoning in man and experimental animals showed that the main effects of CUC are severe depression of respiration, cardiovascular system, the central nervous system and hypoglycaemia. These toxic effects acting singly or in combination are believed to be the cause(s) of death from CUC. Management is geared towards correcting these adverse effects.

Identification and distribution of phenylacetic acid in the brain of the rat.

Phenylacetic acid, the major metabolite of phenylethylamine, has been identified and quantitated in rat brain regions by capillary column high-resolution gas chromatography mass spectrometry. Its distribution is heterogeneous and correlates with that of phenylethylamine. The values obtained were (ng/g +/- SEM): whole brain, 31.2 +/- 2.7; caudate nucleus, 64.6 +/- 6.5; hypothalamus, 60.1 +/- 7.4; cerebellum, 31.3 +/- 2.9; brainstem, 33.1 +/- 3.3, and the "rest," 27.6 +/- 3.0.

Distribution of norepinephrine, epinephrine, dopamine, serotonin, 3,4-dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindole-3-acetic acid in dog brain.

The distribution and endogenous concentrations of norepinephrine, epinephrine, dopamine, serotonin, 3,4-dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindole-3-acetic acid were determined in the brains of adult dogs. Norepinephrine and epinephrine were localized primarily in 'central core' areas in brain stem and hypothalamus. Dopamine (DA) and its major metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acids (HVA), were localized primarily in basal ganglia with relatively high concentrations also found in amygdala, septum and substantia nigra. HVA was also found in relatively high concentrations in areas where DA concentrations was very low. Serotonin and 5-hydroxyindole-3-acetic acid levels were highest in brain stem, hypothalamus, globus pallidus and nucleus accumbens. Epinephrine levels were higher than in previously studied species, at times as much as 25-30% of norepinephrine and frequently greater than dopamine in brain stem and hypothalamus. Using the ratios 5-hydroxyindole-3-acetic acid/serotonin and homovanillic acid/dopamine as indicators of serotonin and dopamine turnover and utilization, both putative transmitters were found to be generally more highly utilized in areas of lower concentration, especially in brain stem and cortex. Catecholamines were found to be unconjugated in dog brain. DOPAC and HVA were found to exist primarily in the unconjugated form. DOPAC was found to be slightly conjugated in most areas while 10-20% of HVA was present in the conjugated form in most cases.

Identification and distribution of m- and p-hydroxyphenylacetic acids in the brain of the rat.

The m and p isomers of hydroxyphenylacetic acid have been identified and quantitated in whole rat brain and in several regions using a capillary column high resolution gas chromatography - mass spectrometry procedure. Their concentrations were: for m-hydroxyphenylacetic acid (mean +/- S.E., number of determinations in parentheses)-whole brain, 2.3 +/- 0.3 ng/g (7); hypothalamus, 1.2 +/- 0.3 ng/g (5); caudate nucleus, 5.5 +/- 0.6 ng/g (5); brain stem, 1.8 +/- 0.1 ng/g (5); cerebellum, 1.2 +/- 0.1 ng/g (5) and the "rest," 1.7 +/- 0.1 ng/g (5); and for p-hydroxyphenylacetic acid-whole brain, 10.6 +/- 0.7 ng/g (7); hypothalamus, 4.5 +/- 0.1 ng/g (4); caudate nucleus, 28.3 +/- 1.6 ng/g (5); brain stem, 8.6 +/- 0.6 ng/g (5); cerebellum, 8.1 +/- 0.4 ng/g (5), and the "rest," 5.3 +/- 0.5 ng/g (5). This heterogeneous distribution parallels closely that exhibited by their respective precursor amines, m- and p-tyramine.

A radioenzymatic method to measure picogram amounts of dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) in small samples of brain tissue.

A radioenzymatic method for simultaneous determination of dopamine and DOPAC in small brain areas is described. By using this assay, 250 pg of dopamine and 150 pg of DOPAC can be estimated. The present method has been applied to compare the effect of different psychotropic drugs on the dopamine and DOPAC levels in the caudate nucleus, substantia nigra and medial basal hypothalamus.