LC-MS analysis of oils of Monodora myristica and Monodora tenuifolia and isolation of a novel cyclopropane fatty acid

Seeds of Monodora myristica and M. tenuifolia were extracted with hexane and the extractswere subjected to column chromatography, LC-MS and NMR analysis. In addition to masses of previously isolated compounds, other masses corresponding to unidentified compounds from the plants were detected. Using 2D NMR techniques, one of the fractions from M. tenuifolia was characterised as a novel 13-(2-butylcyclopropyl)-6,9-dodecadienoic acid. However, none of the compounds detected in LC-MS corresponded to the ones previously identified by GC-MS

Stockpiling by pups and self-sacrifice by their fasting mothers observed in birth to weaning serum metabolomes of Atlantic grey seals

The work was funded from core support given to the Sea Mammal Research Unit, Scottish Oceans Institute, from the National Environmental Research Council (UK), and separately by the Universities of Glasgow and Strathclyde. The funding of mass spectrometry equipment for metabolomics was provided by the Scottish Life Sciences Alliance.During the uniquely short lactations of true seals, pups acquire a greater proportion of maternal body resources, at a greater rate, than in any other group of mammals. Mothers in many species enter a period of anorexia but must preserve sufficient reserves to fuel hunting and thermoregulation for return to cold seas. Moreover, pups may undergo a period of development after weaning during which they have no maternal care or nutrition. This nutritionally closed system presents a potentially extreme case of conflict between maternal survival and adequate provisioning of offspring, likely presenting strains on their metabolisms. We examined the serum metabolomes of five mother and pup pairs of Atlantic grey seals, Halichoerus grypus, from birth to weaning. Changes with time were particularly evident in pups, with indications of strain in the fat and energy metabolisms of both. Crucially, pups accumulate certain compounds to levels that are dramatically greater than in mothers. These include compounds that pups cannot synthesise themselves, such as pyridoxine/vitamin B6, taurine, some essential amino acids, and a conditionally essential amino acid and its precursor. Fasting mothers therefore appear to mediate stockpiling of critical metabolites in their pups, potentially depleting their own reserves and prompting cessation of lactation.Publisher PDFPeer reviewe

AB-FUBINACA, A SYNTHETIC CANNABINOID IN “FUNKY GREEN STUFF™”

Objective: The objective of this research was to isolate and identify any potential synthetic cannabinoids disguised in the commercially available claimed-to-be herbal scent, known as “Funky Green Stuff™”. Methods: Potential synthetic cannabinoids were extracted via percolating the content of the commercial herbal scent bag “Funky Green StuffTM” in methanol. Column chromatographic isolation afforded one main pure compound. Different spectral analyses established the identity of the isolated compound. Results: Chromatographic purification afforded 372 mg (5.2% w/w enrichment ratio) of pure needle crystals. Spectral analyses revealed the identity of the isolated compound as the synthetic cannabinoid AB-FUBINACA, confirming the assumption that a synthetic cannabinoid was disguised as an herbal scent product. Conclusion: Several scent herbal products, also known as “spice”, are used to disguise synthetic cannabinoids. Their detection proved to be troublesome since authentic standards are not yet available. The synthetic cannabinoid, AB-FUBINACA, was isolated from one of these products, and its identity was established based on its spectral data

A new isoflavone from Lomariopsis guineensis (Underw.) Alston

Aim/background: Lomariopsis guineensis (Underw.) Alston is an epiphytic climbing fern. It is widely distributed in Africa where it is also used in traditional medicine and as food. There are no previous reports of any constituents of the plant, hence this study to isolate any phytoconstituents. Method: The ethyl acetate extract of the leaves was subjected to column chromatography and isolated constituents were characterized using nuclear magnetic resonance and mass spectrometry. Results: Three compounds were isolated and identified as cycloartenol, pheophytin A and a new isoflavone (5, 7-dihydroxy-4′ methoxy-6,8-dimethylisoflavone). Conclusion: Three phytochemicals including a new isoflavone are reported from the plant for the first time

Plasma free fatty acids metabolic profile with LC-MS and appetite-related hormones in South Asian and White European men in relation to adiposity, physical activity and cardiorespiratory fitness : a cross-sectional study

South Asians have a greater cardiovascular disease (CVD) and type 2 diabetes (T2D) risk than white Europeans, but the mechanisms are poorly understood. This study examined ethnic differences in free fatty acids (FFAs) metabolic profile (assessed using liquid chromatography-mass spectrometry), appetite-related hormones and traditional CVD and T2D risk markers in blood samples collected from 16 South Asian and 16 white European men and explored associations with body composition, objectively-measured physical activity and cardiorespiratory fitness. South Asians exhibited higher concentrations of five FFAs (laurate, myristate, palmitate, linolenic, linoleate; p ≤ 0.040), lower acylated ghrelin (ES = 1.00, p = 0.008) and higher leptin (ES = 1.11, p = 0.004) than white Europeans; total peptide YY was similar between groups (p = 0.381). South Asians exhibited elevated fasting insulin, C-reactive protein, interleukin-6, triacylglycerol and ratio of total cholesterol to high-density lipoprotein cholesterol (HDL-C) and lower fasting HDL-C (all ES ≥ 0.74, p ≤ 0.053). Controlling for body fat percentage (assessed using air displacement plethysmography) attenuated these differences. Despite similar habitual moderate-to-vigorous physical activity (ES = 0.18, p = 0.675), V ˙ O2max was lower in South Asians (ES = 1.36, p = 0.001). Circulating FFAs in South Asians were positively correlated with body fat percentage (r2 = 0.92), body mass (r2 = 0.86) and AUC glucose (r2 = 0.89) whereas in white Europeans FFAs were negatively correlated with total step counts (r2 = 0.96). In conclusion, South Asians exhibited a different FFA profile, lower ghrelin, higher leptin, impaired CVD and T2D risk markers and lower cardiorespiratory fitness than white Europeans

Mitochondrial hyperfusion via metabolic sensing of regulatory amino acids

The relationship between nutrient starvation and mitochondrial dynamics is poorly understood. We find that cells facing amino acid starvation display clear mitochondrial fusion as a means to evade mitophagy. Surprisingly, further supplementation of glutamine (Q), leucine (L), and arginine (R) did not reverse, but produced stronger mitochondrial hyperfusion. Interestingly, the hyperfusion response to Q + L + R was dependent upon mitochondrial fusion proteins Mfn1 and Opa1 but was independent of MTORC1. Metabolite profiling indicates that Q + L + R addback replenishes amino acid and nucleotide pools. Inhibition of fumarate hydratase, glutaminolysis, or inosine monophosphate dehydrogenase all block Q + L + R-dependent mitochondrial hyperfusion, which suggests critical roles for the tricarboxylic acid (TCA) cycle and purine biosynthesis in this response. Metabolic tracer analyses further support the idea that supplemented Q promotes purine biosynthesis by serving as a donor of amine groups. We thus describe a metabolic mechanism for direct sensing of cellular amino acids to control mitochondrial fusion and cell fate

Applications of high performance liquid chromatography in the analysis of basic compounds

The development of chromatographic methods for basic drugs can still present problems. Two modes of chromatographic separation were studied in order to assess their performance with regard to the separation of organic bases. Reversed phase chromatography was applied in the assessment of the stability of two extemporaneous formulations of drugs used in hospital for pain relief in palliative care, for which there was no stability information. Three different formulations of the two combinations were assessed. In the case of the diamorphine/clonidine/bupivacaine combination there were no major stability issues apart from the slow hydrolysis of diamorphine to monoacetyl morphine. In a combination containing morphine and levomepromazinemorphine remained stable, but there was a gradual decline in the level of levomepromazine which fell to below 90% of the original concentration after one week. The theme of chromatographic analysis of basic drugs was continued in the second part of the PhD project where silica based alkyl phases were studied with regard to their ability to retain basic drugs under hydrophilic interaction like conditions. It was observed that with mobile phases containing high levels of organic solvent, for example water/acetonitrile (5:95 % v/v) containing 0.025% w/v ammonium acetate, basic compounds were strongly retained. The strength of the retention of the bases depended on the % of water in the mobile phase and the strength of the ammonium acetate. The novel methods developed were applied to drug impurity profiling and fundamental research on mechanisms was carried out using simple basic test probes.The development of chromatographic methods for basic drugs can still present problems. Two modes of chromatographic separation were studied in order to assess their performance with regard to the separation of organic bases. Reversed phase chromatography was applied in the assessment of the stability of two extemporaneous formulations of drugs used in hospital for pain relief in palliative care, for which there was no stability information. Three different formulations of the two combinations were assessed. In the case of the diamorphine/clonidine/bupivacaine combination there were no major stability issues apart from the slow hydrolysis of diamorphine to monoacetyl morphine. In a combination containing morphine and levomepromazinemorphine remained stable, but there was a gradual decline in the level of levomepromazine which fell to below 90% of the original concentration after one week. The theme of chromatographic analysis of basic drugs was continued in the second part of the PhD project where silica based alkyl phases were studied with regard to their ability to retain basic drugs under hydrophilic interaction like conditions. It was observed that with mobile phases containing high levels of organic solvent, for example water/acetonitrile (5:95 % v/v) containing 0.025% w/v ammonium acetate, basic compounds were strongly retained. The strength of the retention of the bases depended on the % of water in the mobile phase and the strength of the ammonium acetate. The novel methods developed were applied to drug impurity profiling and fundamental research on mechanisms was carried out using simple basic test probes

UHPLC-UV Method for Simultaneous Determination of Perindopril Arginine and Indapamide Hemihydrate in Combined Dosage Form: A Stability-Indicating Assay Method

Perindopril arginine and Indapamide hemihydrate in combination were proven to have a synergistic antihypertensive impact when compared with the use of each component alone. Therefore, a new Ultra-High Performance Liquid Chromatography coupled with Ultraviolet detector (UHPLC-UV) method has been developed and subsequently validated for simultaneous determination of the anti-hypertensive combination of Perindopril arginine and Indapamide hemihydrate. The separation of Perindopril arginine and Indapamide hemihydrate was achieved using a BEH C18 (1.7 μm, 2.1 × 50 mm) analytical column (Waters® Acquity UPLC) and a mobile phase composed of 0.01% v/v formic acid in water adjusted to pH 4 with acetic acid and acetonitrile (40:60 v/v). The method was able to separate Perindopril arginine and Indapamide hemihydrate within less than 4.5 min with high accuracy, precision, resolution, and sensitivity. The content of Perindopril arginine and Indapamide hemihydrate present in the dosage form Coversyl Plus® (5000 µg of Perindopril arginine/1250 µg of Indapamide hemihydrate) was determined in triplicate to give a concentration of 4991 µg and 1247 µg, respectively, from the manufacturer’s stated amounts with Relative Standard Deviation (%RSD) of ±0.63% for Perindopril arginine and ±0.84% for Indapamide hemihydrate. Moreover, the degradation products of the combination were elucidated by UHPLC-Quadrupole Time of Flight-Mass spectrometry (UHPLC-QToF-MS) under acidic, basic, and thermal conditions. In conclusion, the developed UHPLC-UV method was sensitive, rapid, and precise. Furthermore, forced degradation studies were performed and the degradants were identified by UHPLC-Electro-Spray Ionization-QToF (UHPLC-ESI-QToF)

Eco-Friendly Separation of Antihyperlipidemic Combination Using UHPLC Particle-Packed and Monolithic Columns by Applying Green Analytical Chemistry Principles

Efficient separation of pharmaceuticals and metabolites with the adequate resolution is a key factor in choosing the most suitable chromatographic method. For quality control, the analysis time is a key factor, especially in pharmacokinetic studies. High back pressure is considered as one of the most important factors in chromatography’s flow control, especially in UHPLC. The separation of the anti-hyperlipidemic mixtures was carried out using two columns: a column silica-based particle packed UHPLC and a monolithic column. The systematic suitability of the two columns was compared for the separation of Fenofibrate, its active metabolite, Fenofibric acid and Pravastatin using Atorvastatin as an internal standard. Separation on both columns was obtained using ethanol: buffer potassium dihydrogen orthophosphate pH = 3 (adjusted with orthophosphoric acid) (75:25 v/v) as mobile phase and flow rate 0.8 mL/min. The analytes’ peak detection was achieved by using a PDA detector at 287 nm, 214 nm, 236 nm, and 250 nm for Fenofibrate, Fenofibric acid, Pravastatin, and Atorvastatin, respectively. Reduction of back-pressure was achieved with the monolithic column, where the analytes could be completely separated in less than 1.5 min at a flow rate of 5 mL/min. The principles of Green Analytical Chemistry (GAC) were followed throughout the developed method using environmentally safe solvents

Remdesivir—Bringing Hope for COVID-19 Treatment

At the beginning of 2020, the world was swept with a wave of a new coronavirus disease, named COVID-19 by the World Health Organization (WHO 2). The causative agent of this infection is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The data available on one of the promising therapeutic agents—nucleotide analog remdesivir (Gilead Sciences number GS-5734)—were evaluated. These data were concerned with remdesivir activation from the prodrug to the active molecule—triphosphate containing 1′-cyano group and modified nucleobase. This triphosphate competes with the natural substrate adenosine triphosphate. Additionally, its mechanisms of action based on RNA and proofreading exonuclease inhibition, leading to the delayed RNA chain termination of infected cells, and basic pharmacological data were assessed. Additionally, the analytical determination of remdesivir and its metabolites in cells and body liquids and also some data from remdesivir use in other RNA infections—such as Ebola, Nipah virus infection, and Middle East Respiratory Syndrome (MERS)—were summarized. More recent and more detailed data on the clinical use of remdesivir in COVID-19 were reported, showing the intensive efforts of clinicians and scientists to develop a cure for this new disease. Remdesivir as such represents one of the more promising alternatives for COVID-19 therapy, however the current understanding of this disease and the possible ways of dealing with it requires further investigation