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During routine screening of illegal adulterants in health supplements, a novel sildenafil analogue was discovered, and subsequently isolated by recrystallization. Its structure was elucidated by extensive analyses of high resolution mass spectrometry (HRMS), one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) data. The analogue was finally determined as hydroxycarbodenafil, featuring a hydroxyethyl group instead of an ethyl group on piperazine ring in comparison with carbodenafil., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Cysteine is a sulfur-containing amino acid which plays an outstanding role in many biological pathways in mammals. The analysis and quantification of native cysteine remains a critical issue due to its highly reactive thiol group evolving to the disulfide cystine derivative through oxidation reaction. Aimed at improving the derivative stability, cysteine was labelled with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F), which reacts with both amino and thiol groups. The derivatization was optimized and the chemical identity of the reaction product was assessed via high-resolution mass spectrometry. The NBD-cysteine derivative resulted stable for 10 days. This derivative was enantioresolved (α and R S equal to 1.25 and 2.70, respectively) thanks to a (R,R)-Whelk-O1 phase with the following chromatographic setting: eluent, MeOH/water-90/10 (v/v) with 15 mM ammonium formate (pwsH 6.0); column temperature, 35 °C; flow rate, 1.0 mL/min. The developed method was validated following the ICH guidelines and applied for the quality control of a L-cysteine containing dietary supplement., (Copyright © 2019 Elsevier B.V. All rights reserved.)

An UHPLC method was developed for the determination of 15 prenylflavonoids from aerial parts of Epimedium grandiflorum and related species (Berberidaceae). The separation was achieved using a reverse phased column and water/acetonitrile gradient as a mobile phase at a temperature of 40°C. The developed analytical method was validated for linearity, limits of detection (LOD) and limits of quantification (LOQ), stability and repeatability. The LOD and LOQ were found to be in the range from 0.1-0.5 μg/mL and 0.3-1 μg/mL, respectively. The wavelength used for quantification with the photodiode array detector was 269 nm. The total content of 15 prenylflavonoids was 9.1-20.6 mg/g for E. grandiflorum (except for sample #2899 and #20862), 5.6-35.4 mg/g for E. brevicornu and 10.8-30.5 mg/g for E. sagittatum. Twenty dietary supplements contained in the range from 0.1 to 81.7 mg/day. The developed method is simple, rapid and especially suitable for quality assessment of E. grandiflorum and dietary supplements containing E. grandiflorum. Liquid chromatography quadrupole time-of-flight-mass spectrometry (LC-QToF) is described for the identification and confirmation of compounds in plant samples and dietary supplements. This technique is also used for chemical profiling of Epimedium samples. This method involved the use of protonated ions in the positive ion mode and deprotonated ions in the negative ion mode with extracted ion chromatogram (EIC). Chemometric analytical tools for visualizing the plant and commercial samples quality were used for discriminating between Epimedium species and dietary supplements with regards to the relative content or presence of components. A HPTLC method was also developed for the fast chemical fingerprint analysis of Epimedium species., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The present study aimed to design, develop, and optimize an analytical procedure to perform the quantitative determination of ecdysterone in commercially available dietary supplements. The newly developed procedure is based on the extraction of ecdysterone from the supplements and the subsequent analysis by an optimized UHPLC-MS/MS method. Chromatographic separation was performed on an Agilent Eclipse Plus C18 column (2.1 mm x 100 mm, particle size 1.8 μm). The mass spectrometer was operated in positive ionization mode (ESI+) with acquisition in dynamic multiple reaction monitoring (dMRM) mode. Using the protonated molecular ion [M+H] + ecdysterone (target) and cortisol (internal reference) were detected at m/z 481 and 363, respectively. The assay was fully validated according to ICH guidelines and the method resulted to be fit for purpose in terms of accuracy and precision (CV% and RE% <15). Time-different intermediate precision was found within the reported range according to AOAC guideline for dietary supplements and botanicals. Quantitation has been performed using an external calibration considering the minimal matrix influences, preliminarily assessed following a cross comparison with an elaborate and time consuming standard addition method. The method was successfully applied to 12 different dietary supplements labelled to contain ecdysterone, showing an actual content generally much lower than the labelled one., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Use of herbal medicines and supplements by consumers to prevent or treat disease, particularly chronic conditions continues to grow, leading to increased awareness of the minimal regulation standards in many countries. Fraudulent, adulterated and contaminated herbal and traditional medicines and dietary supplements are a risk to consumer health, with adverse effects and events including overdose, drug-herb interactions and hospitalisation. The scope of the risk has been difficult to determine, prompting calls for new approaches, such as the combination of DNA metabarcoding and mass spectrometry used in this study. Here we show that nearly 50% of products tested had contamination issues, in terms of DNA, chemical composition or both. Two samples were clear cases of pharmaceutical adulteration, including a combination of paracetamol and chlorpheniramine in one product and trace amounts of buclizine, a drug no longer in use in Australia, in another. Other issues include the undeclared presence of stimulants such as caffeine, synephrine or ephedrine. DNA data highlighted potential allergy concerns (nuts, wheat), presence of potential toxins (Neem oil) and animal ingredients (reindeer, frog, shrew), and possible substitution of bird cartilage in place of shark. Only 21% of the tested products were able to have at least one ingredient corroborated by DNA sequencing. This study demonstrates that, despite current monitoring approaches, contaminated and adulterated products are still reaching the consumer. We suggest that a better solution is stronger pre-market evaluation, using techniques such as that outlined in this study., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A previously unidentified purported botanical ingredient was found in dietary supplements marketed for anabolic benefits. In an attempt to assess the 'naturalness' of a group of steroid-like compounds called laxogenins, a UHPLC-QToF method was developed. Several dietary supplements claim to contain 5α-hydroxy laxogenin, which is a derivative of a naturally occurring spirostane-type steroid, laxogenin. Although laxogenin has been isolated from the rhizomes of Smilax sieboldii, 5α-hydroxy laxogenin has not been isolated or reported from any natural source. These derivatives of laxogenins have untested anabolic properties. Due to the low UV absorbance of the spirostanes, a mass spectrometric method in positive ion mode was developed for unambiguous identification of laxogenin and closely related compounds. To show the utility of the developed method, twelve dietary supplements labeled to contain 5α-hydroxy laxogenin or laxogenin as 5α-hydroxy laxogenin were analyzed as a proof-of-concept. Five supplements did not contain any 5α-hydroxy laxogenin, whereas in the remaining seven samples, spirostane-type contaminants were identified along with the labeled 5α-hydroxy laxogenin. The identity of some of these contaminants was established based on reference standards along with mass fragmentation patterns. One of the unlabeled contaminants was identified as the phytosteroid saponin, diosgenin, a common starting precursor of several steroidal drugs. Several synthetic derivatives of diosgenin were identified in the eight products. These findings indicate that the labeled 5α-hydroxy laxogenin along with other spirostanes found in supplements are synthetic and signify a lack of quality controls. Additionally, an unlabeled, anabolic androgenic steroid, arimistane, an aromatase inhibitor, was also identified in one product. Laxogenin, was not detected in any of the samples analyzed during this investigation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The sale and consumption of plant food supplements is increasing, especially in the western world. A lot of these supplements can be bought through internet, where a lot of illegal trade is going on. Every year seized dietary supplements are send to laboratories in order to screen for the presence of chemical adulterants or illegally added active pharmaceutical ingredients, though also herbal adulteration occurs and is given less attention. In this paper a two-step approach is presented based on fingerprints recorded by both infrared spectroscopy as liquid chromatography with UV-detection for the screening of five regulated plants used in respectively dietary supplements for slimming and potency enhancement. Both types of fingerprints are combined with chemometric techniques in order to obtain classification models. A first classification model is calculated based on the infrared data and gives a first idea about the plant suspected to be present. This suspicion is then confirmed based on binary classification models calculated with the chromatographic data obtained for the suspected plant. In general, good classification models were obtained for each of the targeted plants. The approach was applied in a small market study comprising 35 dietary supplements for slimming and 34 for male potency enhancement. In total 21 samples were found to contain one of the five targeted plants., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Popularity of natural-based preparations supporting the sexual potency significantly increased in recent years, which also led to the increase of illegal use of phosphodiesterase type 5 inhibitor (PDE-5) in sexual performance enhancement products. In this study, a rapid U-HPLC‒HRMS/MS method has been developed to simultaneously determine 59 PDE-5 inhibitors and their analogues. Within the development of sensitive method for analysis of 59 PDE-5 inhibitors and their analogues, both sample preparation procedure, as well as separation / detection conditions have been optimized. Extraction efficiency of particular extraction solvents, influence of different mobile phase additives on target analytes separation, as well as impact of various settings of mass analyzer on sensitivity of detection were examined. Data were collected in the 'full MS/data dependent MS/MS' acquisition mode (full MS-dd-MS/MS). Before the U-HPLC‒HRMS/MS method was used for analysis of real samples, proper validation had been conducted. The precision of the method expressed as the relative standard deviation (RSD) was ≤4.2% and ≤5.2% at spiking concentrations 5 μg/g and 0.25 μg/g, respectively. The limits of quantification were in the range 0.25 - 0.05 μg/g and the recovery ranged between 71 and 90%. The optimized method was successfully applied for analysis of 64 real samples, and 10 of them were proved to contain both registered or unregistered synthetic PDE-5 inhibitors. Additionally, the acquired U-HPLC‒HRMS/MS fingerprints were demonstrated to serve as an efficient tool for revealing of other type of possible fraud in products labeling. Retrospective mining of markers of herbs declared on dietary supplements packaging allowed to assess the trueness / untruth in the declaration of medical herbs composition., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Siberian ginseng (Eleutherococcus senticosus, Araliaceae) and roseroot (Rhodiola rosea, Rosaceae) are popular herbal supplements which have been shown to improve resilience to conditions such as stress and exhaustion. Using DNA barcoding methods we tested 25 Siberian ginseng and 14 roseroot products which are widely available to UK customers to test whether the herbal ingredient stated on the label is also in the product. All Siberian ginseng supplements contained E. senticosus, however, 36% also contained an Eleutherococcus species other than E. senticosus. In three out of the 13 roseroot products which produced amplifiable DNA, we could only retrieve sequences matching alfalfa (declared on the product label) and fenugreek (not declared). In the other 10 supplements Rhodiola was detected but only five matched the target species R. rosea. As DNA can get severely degraded during the manufacturing process we did not take the absence of Rhodiola DNA as proof for a compromised product. Contamination could explain the presence of non-target species such as fenugreek but is unlikely to be account for the detection of congeneric Rhodiola species in roseroot preparations. Our results therefore suggest that the substitution or mixing of the target medicinal ingredient in these two popular supplements with other species is common., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: Controlling antioxidant supplementation in athletes involved in studies related to oxidative stress and muscle damage is the key to ensure results. The aim of this study was to confirm through high-performance liquid chromatography (HPLC) analysis whether well-trained individuals lied during a personal interview when asked if they were taking supplements with antioxidants, and how this could affect oxidative stress, muscle damage, and antioxidant response., Methods: A total of 94 men, well trained in endurance sports, volunteered in this study. They denied taking any antioxidant supplementation at initial interview. After a HPLC analysis, abnormal α-tocopherol concentrations were detected, probably due to a hidden antioxidant supplementation. Participants were classified into two groups: no evidence of antioxidant supplementation (NS group = α-tocopherol values <80 nmol/mL; n = 75) and evidence of antioxidant supplementation (S group = α-tocopherol values >80 nmol/mL; n = 19). Lipid peroxidation, muscle damage, antioxidant enzyme activity, and nonenzymatic antioxidant content were analyzed according to this classification. Statistical comparisons were performed using Student's t test., Results: The α-tocopherol concentrations were significantly higher in the S group than in the NS group (MD = 725.01 ± 39.01 nmol/mL; P = 0.001). The S group showed a trend toward lower hydroperoxides than the NS group (MD = 1.19 ± 0.72 nmol/mL; P = 0.071). The S group showed significantly lower catalase activity than the NS group (MD = 0.10 ± 0.02-seg-1 mg-1; P < 0.01). Skeletal muscle damage markers did not differ between experimental groups., Conclusions: Data from the present study reveal that 20% of participants lied in the exclusion criteria of antioxidant supplementation in a personal interview, as they showed high plasmatic α-tocopherol concentrations after HPLC verification. Catalase activity seems to be affected by high α-tocopherol plasma levels. Therefore, we strongly recommend the HPLC analysis as a necessary tool to verify the antioxidant intake and preserve results in studies linking oxidative stress and sport., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Red yeast rice (RYR) is prepared by fermenting rice with various strains of the yeast Monascus spp of the Aspergillaceae family. Depending on the Monascus strains and the fermentation conditions, the products may contain monacolins, pigments and citrinin as secondary metabolites. Authentic and commercial RYR samples were analyzed using UHPLC-DAD-QToF-MS for monacolins, pigments and citrinin. A separation by UHPLC was achieved using a reversed-phase column and a gradient of water/acetonitrile each containing formic acid as the mobile phase. Accurate mass QToF spectrometry was used to distinguish isobaric monacolins. Principle component analysis (PCA), a chemometric technique was used to discriminate between authentic RYR, commercial RYR raw materials and dietary supplements. Three authentic RYR samples, 31 commercial RYR raw materials and 14 RYR dietary supplements were analyzed. Monacolin K content in 600mg of authentic RYR samples ranged from 1.2mg to 1.38mg. Amounts of monacolin K in dietary supplements labeled as containing 600mg of RYR varied more than 40-fold from 0.03mg to 2.18mg. Monacolin K content of dietary supplements labeled as containing 1200mg RYR varied more than 20-fold from 0.22mg to 5.23mg. In addition to large variations in quantity of monacolin K found in dietary supplements, RYR dietary supplements contained ratios of monacolins that differed significantly from authentic samples. The results indicated that RYR commercial products are of variable quality and the analytical method is suitable for quality control testing of a variety of RYR products., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A dietary supplement sold in erotic shops was analysed. It contains dithiodesmethylcarbodenafil as the major component, which was already reported as an adulterant in dietary supplements. Additionally three more compounds were found and their structures were elucidated after isolation using NMR and mass spectroscopy. They were designated as isonitrosoprodenafil, dithiodesethylcarbodenafil and norcarbodenafil., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Previously, we have reported the pharmacokinetic (PK) properties of α-mangostin in mice. For this study, we evaluated the PK profile of α-mangostin using a standardized mangosteen extract in C57BL/6 mice. The primary objective was to determine the PK properties of α-mangostin when administered as an extract. This experiment was designed to test our primary hypothesis that α-mangostin in an extract should achieve a desirable PK profile. This is especially relevant as dietary supplements of mangosteen fruit are regularly standardized to α-mangostin. Mice received 100 mg/kg of mangosteen fruit extract orally, equivalent to 36 mg/kg of α-mangostin, and plasma samples were analyzed over a 24-hour period. Concentrations of α-mangostin were determined by liquid chromatography-tandem mass spectrometry. In addition, we evaluated the stability in the presence of phase I and phase II enzymes in liver and gastrointestinal microsomes. Furthermore, we identified evidence of phase II metabolism of α-mangostin. Further research will be required to determine if less abundant xanthones present in the mangosteen may modulate the PK parameters of α-mangostin., (Copyright © 2014 Elsevier Inc. All rights reserved.)

A new derivative of vardenafil was detected in an alleged herbal dietary supplement and identified as 2-(2-ethoxy-5-(4-(2-hydroxyethyl)piperazin-1-ylsulfonyl)phenyl)-5-methyl-7-propyl-imidazo[1,5-f][1,2,4]triazin-4(3H)-thione. Structure elucidation was carried out by LC-UV-MS/MS and NMR. Results obtained with high resolution MS and IR spectroscopy confirmed the proposed chemical structure. The compound was distinguished from hydroxyvardenafil, a second active substance identified in the same product, by the conversion of the oxo group to a thio group on the imidazo-triazin moiety. Hydroxythiovardenafil was therefore suggested as a proprietary name for the new molecule. This is the first paper to describe a thio-analog of vardenafil in a commercially available product., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Headspace solid phase microextraction (HSSPME) of chemically generated selenium hydride from alkaline solution followed by thermal desorption (TD) coupled directly to a microwave plasma (MWP) source has been examined for the optical emission spectrometric (OES) determination of Se. Various chemical and operating parameters including the NaBH(4) and HCl concentrations as well as the fiber exposure time and desorption temperature have been optimized. Alternatively, continuous hydride generation (HG) from alkaline medium and inductively coupled plasma (ICP) may be used for Se determination by OES. With the procedure developed, the determination of Se in dietary supplements at the tens of μgg(-1) level and an accuracy of 3-6% could be performed even in the presence of the 1000-fold excess of Fe and Cu. Additionally, Se was determined in the NIST 8418 material (Wheat gluten) with a certified concentration of Se of 2.58 ± 0.19 μgg(-1), and a value of 2.45 ± 0.25 μgg(-1) was found using HG-HSSPME-MWP-OES. The detection limit for Se (3.2 ng ml(-1)) with the proposed procedure was comparable to those obtained with HG-ICP-OES and the calibration curve was linear of about 2 orders of magnitude., (Copyright © 2012 Elsevier B.V. All rights reserved.)

UPLC-UV and HPLC-TOF-MS methods have been developed for the analysis of major sesquiterpenes and pyrrolizidine alkaloids from rhizomes of Petasites hybridus (L.) G.M. et Sch. (Family, Asteracea) and dietary supplements claiming to contain P. hybridus. The best results were obtained with Acquity UPLC™ HSS T3 (100 mm × 2.1 mm, I.D., 1.8 μm) column system using a gradient elution with a mobile phase consisting of ammonium formate (50mM) and acetonitrile (0.05% formic acid) at a constant flow rate of 0.25 mL/min via UPLC-UV. The newly developed method was validated according to the ICH guidelines with respect to specificity, linearity, accuracy and precision. The limits of detection were found to be 5 μg/mL and 0.1 μg/mL for pyrrolizidine alkaloids and sesquiterpenes, respectively by UPLC-UV and 0.001 and 0.01 μg/mL, respectively using HPLC-TOF-MS. The methods were successfully used to analyze different P. hybridus market products, as well as to distinguish between two other Petasites species. The total content of petasins was found to be in the range of 0.02-11.6 mg/dosage form for 15 dietary supplements and no petasins were detected in an additional six dietary supplements. Additionally, pyrrolizidine alkaloids, which are considered to be toxic for the liver, were detected in seven dietary supplements. The amount of petasin in seven dietary supplements was found to be within limits of label claim and no pyrrolizidine alkaloids were detected. HPLC-mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification and confirmation of sesquiterpenes and pyrrolizidine alkaloids from plant extracts and dietary supplements that claim to contain P. hybridus as well as different species of Petasites., (Copyright © 2012 Elsevier B.V. All rights reserved.)

During routine screenings of two "libido enhancer" dietary supplements using LC-MS(n), two compounds were detected that displayed structural similarities to tadalafil. These compounds were isolated from the supplements using high-performance liquid chromatography with fraction collection, and were characterized further using accurate mass determination and NMR. "Compound 1" had an m/z of 434 for the [M+H]⁺ ion, with a corresponding chemical formula of C₂₄H₂₄N₃O₅. "Compound 2" had an m/z of 432 for the [M+H]⁺ ion, with a corresponding chemical formula of C₂₅H₂₆N₃O₄. Although mass spectrometry indicated that these modifications occurred in place of the -CH₃ found on the pyrazinopyridoindole-1,4-dione of tadalafil, NMR was required to elucidate the correct configurations of these substitutions. The data obtained using NMR indicated that the structure of the -C₃H₇O moiety found in Compound 1 was 2-hydroxypropyl, and the -C₄H₉ in Compound 2 was n-butyl. These new analogs were given the names 2-hydroxypropylnortadalafil and n-butylnortadalafil, respectively., (Published by Elsevier B.V.)

A fully validated UHPLC-DAD method for the identification and quantification of pharmaceutical preparations, containing molecules frequently found in illegal slimming products (sibutramine, modafinil, ephedrine, nor-ephedrine, metformin, theophyllin, caffeine, diethylpropion and orlistat) was developed. The proposed method uses a Vision HT C18-B column (2 mm × 100 mm, 1.5 μm) with a gradient using an ammonium acetate buffer pH 5.0 as aqueous phase and acetonitrile as organic modifier. The obtained method was fully validated based on its measurement uncertainty (accuracy profile). Calibration lines for all components were linear within the studied ranges. The relative bias and the relative standard deviations for all components were respectively smaller than 3.0% and 1.5%, the β-expectation tolerance limits did not exceed the acceptance limits of 10% and the relative expanded uncertainties were smaller than 3% for all of the considered components. A UHPLC-DAD method was obtained for the identification and quantification of these kind of pharmaceutical preparations, which will significantly reduce analysis times and workload for the laboratories charged with the quality control of these preparations and which can, if necessary, be coupled to a MS-detector for a more thorough characterisation., (Copyright © 2011 Elsevier B.V. All rights reserved.)

iErect, a new dietary supplement marketed as "100% natural" and sold over the Internet, was analyzed. It contains thiosildenafil, a sildenafil analogue already reported as an adulterant in herbal formulations, and a new compound whose structure was elucidated after isolation using NMR, MS and IR. It was named depiperazinothiosildenafil as it results from the hydrolytic cleavage of the S-N bond of the sulfonamide group of thiosildenafil. A capsule of iErect contains a very high amount (≈220mg) of thiosildenafil and ≈30mg of depiperazinothiosildenafil, which places consumers at risk for potentially serious side-effects., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Tocotrienols (T(3)) belong to the family of vitamin E compounds (α-, β-, γ-, δ-tocopherols and -tocotrienols) and have unique biological properties that make them potential neuroprotective dietary factors. In addition to their antioxidant activity, T(3) at micromolar concentrations exert cholesterol-lowering activities in cells, animal models and some, but not all, human studies by means of inhibition of the activity of the rate-limiting enzyme in cholesterol biosynthesis, 3-hydroxy-3-methylglutaryl coenzyme A reductase. At lower concentrations (∼10 nmol/L), T(3) modulate signalling pathways involved in neuronal cell death in cell culture experiments. Targets of T(3) include prenyl transferases, non-receptor tyrosine kinase, phospholipase A(2), 12-lipoxygenase, cyclooxygenase-2, and nuclear factor κB. The low bioavailability and rapid excretion of T(3) represents a major hurdle in their preventive use. Fasting plasma concentrations, even after supplementation with high doses, are below 1 μmol/L. T(3) bioavailability may be enhanced by ingestion with a high-fat meal, self-emulsifying drug delivery systems, or phytochemicals that inhibit T(3) metabolism and excretion. T(3) have no known adverse effects when consumed as part of a normal diet and the studies reviewed here support the notion that they may have potential as neuroprotective agents. However, experiments in relevant animal models and randomised human intervention trials addressing the neuroprotection mediated by T(3) are scarce and, thus, highly warranted., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The aim of this study was to demonstrate the usefulness of the size exclusion chromatography with evaporative light scattering detection (SEC-ELSD) method in the identification and quantitative analysis of polydimethylsiloxanes (PDMS). The process of validation for the method was conducted, and the values obtained were compared with the acceptance criteria. Particularly important was the conclusion that SEC-ELSD method showed a high specificity for PDMS. PDMS is an organosilicon polymer and for this reason, it does not exist as a concrete chemical species. Depending on the length of the chain, PDMS can be toxic for organism. So far, the SEC-ELSD method has not been applied for the control of pharmaceutical products containing such PDMS as dimeticone or simeticone. The safety of use and effectiveness of such pharmaceutical products relies on the control of their quality. Therefore, the analytical methods and procedures that meet acceptance criteria for qualitative and quantitative analysis of the PDMS should be used. In the case of the analysis of pharmaceutical products, the acceptance criteria are established and recommended by, for example, the Pharmacopoeias, the U.S. Food and Drug Administration (FDA), the International Conference on Harmonisation (ICH) and the World Health Organization (WHO). The progress of knowledge, however, requires the development of new analytical tools which are able to solve incoming problems. In the case of pharmaceutical formulations containing PDMS, which are used not only by adults but also by children, it is necessary to use analytical methods which are characterized by a high specificity., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Undernutrition without malnutrition is an intervention that enhances laboratory animal life span, and is widely studied to uncover factors limiting longevity. In a search of the literature over a course of four years, we found that most protocols currently adopted as caloric restriction do not meet micronutrient standards set by the National Research Council for laboratory rats and mice. We provide evidence that the most commonly adopted caloric restriction protocol, a 40% restriction of the AIN-93 diet without vitamin or mineral supplementation, leads to malnutrition in both mice and rats. Furthermore, others and we find that every other day feeding, another dietary intervention often referred to as caloric restriction, does not limit the total amount of calories consumed. Altogether, we propose that the term "caloric restriction" should be used specifically to describe diets that decrease calorie intake but not micronutrient availability, and that protocols adopted should be described in detail in order to allow for comparisons and better understanding of the effects of these diets., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Seventeen herbal dietary supplements, marketed as natural substances for the enhancement of sexual function, were analyzed by diffusion ordered spectroscopy (DOSY) (1)H NMR. The method allowed a global analysis of the samples with detection of both active and inactive ingredients present in these complex matrixes. Eight formulations contained compounds related to the synthetic phosphodiesterase-5 inhibitors. Sildenafil, tadalafil, vardenafil, hydroxyhomosildenafil, thiosildenafil, and the newly identified adulterant thiomethisosildenafil were detected. Quantification of these active ingredients was carried out by HPLC or NMR. In addition to these actives, about 30 compounds or excipients were characterized. This study ended up with a three-dimensional DOSY-COSY (1)H NMR experiment on a herbal formulation which provided both virtual separation and structural information.

The aim of this study was to estimate the rate of sale and intake level of dietary supplements containing fish oil among inhabitants of Warsaw. The survey was carried out during 25 months in the years 2004 to 2006 in 3 selected drugstores localized in the central areas of Warsaw. The amount of fish oil, level of omega-3 long-chain polyunsaturated fatty acids declared on the label, price and rate of sale of particular supplements, as well as the reasons why customers purchased the supplements were collected and analyzed. The rate of sale of fish oil supplements was low; however, it showed a tendency for increase during the time of evaluation. Strong seasonal variability of supplements sale and therefore intake were observed. The highest levels for these parameters occurred from October to February and the lowest from May to July. The most often purchased supplements were fish liver oil capsules. The main reason for fish oil supplement purchases was medical recommendations. The health benefits of fish liver oil were known among customers of drugstores; however, the term omega-3 was almost unknown.

Alpha-lipoic acid is an antioxidant used both in the prevention and treatment of various oxidative stress related diseases. It is an important constituent of some dietary supplements and can also be found in plant and animal sources. A rapid method for the determination of alpha-lipoic acid in dietary supplements based on high performance liquid chromatography coupled with a coulometric electrode array detector (CEAD) and an electrospray ionization mass spectrometer (ESI-MS) was developed. First, alpha-lipoic acid was extracted with methanol by sonication, chromatographic separation was then achieved by isocratic elution [acetonitrile/methanol/50mM potassium dihydrogen phosphate (pH 3, adjusted with phosphoric acid): 350/65/585, v/v/v] using an ACE 3-C-18 column at a flow rate of 0.45 ml/min. alpha-Lipoic acid was detected by means of a CEAD at +300, +400, +450, +500, +550, +600, +650, and +700 mV against palladium reference electrodes. For ESI-MS detection (negative mode), the composition of the mobile phase was changed to 0.1% acetic acid in water/acetonitrile 55:45, v/v applying a flow rate of 0.2 ml/min. The presented methods were utilized to determine the alpha-lipoic acid content in six dietary supplements. The results of both detection modes were in good correlation.

The intensive research carried out in the last 10 years on the unique biological functions of n-3 fatty acids (FA), has promoted comparative investigations on various aspects (metabolic, functional) of the biology of n-6 FA. The involvement of peroxisomes in fatty acid metabolism, initially described for the n-3 acids, has now been shown also for the n-6 FA (formation of 22 carbon delta 4 unsaturated FA, formation of newly identified products of beta-oxidation of arachidonic acid, AA). Additional pathways of AA conversion, beyond the classical eicosanoids, give rise to a series of biologically active products, such as the epoxides, involved in the modulation of vascular functions, through the cytochrome p450 system, and to the AA-ethanolamide, anandamide, an endogenous ligand of the cannabinoid receptors, through a phospholipase-mediated process. Finally, nonenzymatic oxidation products of AA, the isoprostanes, isomers of prostaglandins, also endowed of potent biological activities, are generated both in in vitro-induced lipid oxidation and in vivo, being considered as reliable markers of in vivo oxidative stress. As to the nutritional aspects of the n-6 FA, attention is now paid to the intake of preformed long-chain polyunsaturated FA (PUFA) in the n-6 series, mainly AA, through the diet, in analogy with the intake of the long-chain n-3 FA, in fish-eating populations. The importance of the dietary intake of preformed AA is now recognized in newborns, through maternal milk. The ranges of the intakes of AA in population groups, not currently adequately estimated, appear to be wider than generally assumed, and the elevated intakes in some population groups, in the order of several hundred milligrams per day, may be partly responsible of yet unexplored population-based differences in physiologic variables. Recent research on the functional effects of n-6 FA has confirmed their lipid-lowering effects, which can be observed also in neonates, and has shown that, in cooperation with the n-3, they directly and indirectly contribute to modulate functional parameters at the cellular level, such as receptor function, ion channels, and gene expression. From a nutritional point of view, it is clear that PUFA represent the biologically most active component of dietary fat, and the n-6 are quantitatively the most relevant fraction in our diet. In the light of the diversified activities of n-6 and n-3 PUFA, a correct balance between the various fatty acids is recommended.