Validation and optimisation of reduced glutathione quantification in erythrocytes by means of a coulometric high-performance liquid chromatography analytical method.

Glutathione (GSH), a tripeptide that consists of cysteine, glutamate and glycine, is present in all mammalian tissues in the millimolar range. Besides having numerous cellular functions, GSH is an important antioxidant and is considered a valuable biomarker in evaluating oxidative stress. This paper provides a sensitive analytical method using HPLC-ECD to quantify GSH in erythrocytes, validated using the ICH guidelines for Bioanalytical Method Validation.

UPLC-TQD-MS/MS Method Validation for Quality Control of Alkaloid Content in (Maca)-Containing Food and Dietary Supplements.

Walp. (Brassicaceae), also known as Maca or Peruvian ginseng, is a common ingredient in food supplements with many claimed health benefits, such as improved endurance, increased energy level, and enhanced sexual properties. Due to potential toxicity of its chemicals, including alkaloids, some regulatory authorities, e.

HILIC UPLC/ QTof MS Method Development for the Quantification of AGEs Inhibitors - Trouble Shooting Protocol.

Objective: The paper reports an attempt to develop and validate a HILIC UPLC/ QTof MS method for quantifying N-ε-carboxymethyl-L-lysine (CML) , testing N-ε- carboxy[D]methyl-L-lysine (d-CML), and N-ε-carboxy[4,4,5,5-D]methyl-L-lysine (d-CML) as internal standards.

Methods: During the method development, several challenging questions occurred that hindered the successful completion of the method. The study emphasizes the impact of issues, generally overlooked in the development of similar analytical protocols.

Identification and Quantification of Polymethoxylated Flavonoids in Different Citrus Species Using UPLC-QTOF-MS/MS and HPLC-DAD.

Many species from the genus are used in traditional medicine and contain polymethoxylated flavonoids. These compounds show anti-inflammatory and chemopreventive activities, among others, and therefore have a big potential to be developed as therapeutic agents or dietary supplements. species are different in their profile and yield of polymethoxylated flavonoids.

Alkaloids from Lepidium meyenii (Maca), structural revision of macaridine and UPLC-MS/MS feature-based molecular networking.

Lepidium meyenii Walp., known as Peruvian ginseng, is widely used in ethnomedicine. To date, L.

The presence of benzophenone in sunscreens and cosmetics containing the organic UV filter octocrylene: A laboratory study.

Background: The reason why patients photosensitized to the drug ketoprofen (KP) may develop severe photoallergic skin reactions to octocrylene (OCT), an organic ultraviolet filter in sunscreens and cosmetics, remains largely unknown. OCT can be synthesized by using unsubstituted benzophenone (BP), a possible human carcinogen.

Objectives: To verify if, and to what extent, BP residues are present in OCT-containing consumer products.

In vitro antigenotoxic activity, in silico ADME prediction and protective effects against aflatoxin B induced hepatotoxicity in rats of an Erythrina latissima stem bark extract.

Stem bark of Erythrina latissima E. Mey (Leguminosae) contains a wide range of prenylated flavonoids able to counteract the genotoxic properties of aflatoxin B (AFB). Thus, the hypothesis was raised that E.

In vitro gastrointestinal biotransformation and characterization of a Desmodium adscendens decoction: the first step in unravelling its behaviour in the human body.

Objectives: The isolation and identification of the flavonoids present in a decoction of Desmodium adscendens was performed. In view of the oral use of the decoction, this work focused on the stability in gastrointestinal conditions and biotransformation by intestinal microflora in the colon of D-pinitol, vitexin and the flavonoid fraction of the decoction, as a first step in unravelling its behaviour in the human body.

Methods: The freeze-dried decoction was first subjected to column chromatography.

Advantages of a validated UPLC-MS/MS standard addition method for the quantification of A-type dimeric and trimeric proanthocyanidins in cranberry extracts in comparison with well-known quantification methods.

The berries of Vaccinium macrocarpon, cranberry, are widely used for the prevention of urinary tract infections. This species contains A-type proanthocyanidins (PACs), which intervene in the initial phase of the development of urinary tract infections by preventing the adherence of Escherichia coli by their P-type fimbriae to uroepithelial cells. Unfortunately, the existing clinical studies used different cranberry preparations, which were poorly standardized.

Development and validation of a robust high-performance liquid chromatographic method for the analysis of monacolins in red yeast rice.

A robust analytical method, using reversed phase high-performance liquid chromatography with diode array detection, was developed and validated for the quantification of monacolins in red yeast rice bulk products. Tests on the composition of the extraction solvent, extraction time and the number of repetitions of extraction were evaluated with the aim of complete extraction of the monacolins and minimal transitions between the monacolins during analysis. Monacolin K (acid form), monacolin K (lactone form) and minor monacolin peaks were separated on a C18 column (250×4.

Saponins and Flavonoids from an Infusion of Herniaria hirsuta.

Stone diseases present a major health problem in the Western society, since both urinary and biliary stones occur with a relatively high prevalence of 10-12 % and 10-20 %, respectively, and demonstrate a high recurrence rate. At the moment treatment is mainly based on interventional procedures, or prophylactic and dissolution therapy. However, many of the current drugs cause severe side effects, and therefore, there is an increasing interest in natural medicines.

Cholesterol lowering effect in the gall bladder of dogs by a standardized infusion of Herniaria hirsuta L.

Etnopharmacological Relevance: Infusions of Herniaria hirsuta L., Herniaria glabra L. and Herniaria fontanesii J.

Evaluation of the anti-angiogenic activity of saponins from Maesa lanceolata by different assays.

Angiogenesis, in which a vascular network is established from pre-existing vessels, is a complex multistep process. Mechanisms underlying angiogenesis can be investigated using a variety of in vitro, ex vivo and in vivo approaches. Evaluation of several promising plants and plant metabolites, including terpenoids, revealed promising anti-angiogenic activity.

Impaired fibrillin-1 function promotes features of plaque instability in apolipoprotein E-deficient mice.

Background: Arterial stiffness has been associated with an increased cardiovascular risk. The aim of this study was to investigate the interaction between arterial stiffness and atherosclerosis.

Methods And Results: Mice with a mutation C1039G+/-) in the fibrillin-1 gene leading to fragmentation of the elastic fibers were crossbred with apolipoprotein E-deficient (ApoE-/-) mice.

LC-MS analysis of 13,28-epoxy-oleanane saponins in Maesa spp. extracts with antileishmanial activity.

Introduction: Saponins are natural products that are well known for a wide range of biological activities. For saponins of Maesa balansae, selective antileishmanial activity has been described.

Objective: In view of their pharmacological interest, several Maesa species from the National Botanical Garden of Meise (Belgium) and wild-grown plants from Vietnam were screened for their antileishmanial potential and saponin content.

Determination of saponins in Maesa lanceolata by LC-UV: development and validation.

Triterpene saponins are a class of plant natural products with a wide range of bioactivities, which makes them an interesting research subject. The small tree Maesa lanceolata, growing in African countries, is used in traditional medicine against various diseases. In previous work a triterpenoid saponin mixture was isolated from the leaves of M.

A novel isoflavonoid from Millettia puguensis.

From the roots of Millettia puguensis (Leguminosae), a novel isoflavonoid (5), 2'-methoxy-4',5'-methylenedioxy-7,8-[2-(1-methylethenyl)furo]isoflavone, and four known compounds, i. e., lupeol (1), (-)-maackiain (2), 6,7-dimethoxy-3',4'-methylenedioxyisoflavone (3) and 7,2'-dimethoxy-4',5'-methylenedioxyisoflavone (4) were isolated and identified by 1H-, 13C-NMR and mass spectroscopy.

Flavonoids, NodD1, NodD2, and nod-box NB15 modulate expression of the y4wEFG locus that is required for indole-3-acetic acid synthesis in Rhizobium sp. strain NGR234.

Flavonoids secreted by host plants activate, in conjunction with the transcriptional activator NodD, nod gene expression of rhizobia resulting in the synthesis of Nod factors, which trigger nodule organogenesis. Interestingly, addition of inducing flavonoids also stimulates the production of the phytohormone indole-3-acetic acid (IAA) in several rhizobia. Here, the molecular basis of IAA synthesis in Rhizobium sp.