High placental inositol content associated with suppressed pro-adipogenic effects of maternal glycaemia in offspring: the GUSTO cohort.

BACKGROUND/OBJECTIVES: Maternal glycaemia promotes fetal adiposity. Inositol, an insulin sensitizer, has been trialled for gestational diabetes prevention. The placenta has been implicated in how maternal hyperglycaemia generates fetal pathophysiology, but no studies have examined whether placental inositol biology is altered with maternal hyperglycaemia, nor whether such alterations impact fetal physiology. We aimed to investigate whether the effects of maternal glycaemia on offspring birthweight and adiposity at birth differed across placental inositol levels. METHODS: Using longitudinal data from the Growing Up in Singapore Towards healthy Outcomes cohort, maternal fasting glucose (FPG) and 2-hour plasma glucose (2hPG) were obtained in pregnant women by a 75-g oral glucose tolerance test around 26 weeks' gestation. Relative placental inositol was quantified by liquid chromatography-mass spectrometry. Primary outcomes were birthweight (n = 884) and abdominal adipose tissue (AAT) volumes measured by neonatal MRI scanning in a subset (n = 262) of term singleton pregnancies. Multiple linear regression analyses were performed. RESULTS: Placental inositol was lower in those with higher 2hPG, no exposure to tobacco smoke antenatally, with vaginal delivery and shorter gestation. Positive associations of FPG with birthweight (adjusted ß [95% CI] 164.8 g [109.1, 220.5]) and AAT (17.3 ml [11.9, 22.6] per mmol glucose) were observed, with significant interactions between inositol tertiles and FPG in relation to these outcomes (p < 0.05). Stratification by inositol tertiles showed that each mmol/L increase in FPG was associated with increased birthweight and AAT volume among cases within the lowest (birthweight = 174.2 g [81.2, 267.2], AAT = 21.0 ml [13.1, 28.8]) and middle inositol tertiles (birthweight = 202.0 g [103.8, 300.1], AAT = 19.7 ml [9.7, 29.7]). However, no significant association was found among cases within the highest tertile (birthweight = 81.0 g [-21.2, 183.2], AAT = 0.8 ml [-8.4, 10.0]). CONCLUSIONS: High placental inositol may protect the fetus from the pro-adipogenic effects of maternal glycaemia. Studies are warranted to investigate whether prenatal inositol supplementation can increase placental inositol and reduce fetal adiposity.

Exploitation of artichoke byproducts to obtain bioactive extracts enriched in inositols and caffeoylquinic acids by Microwave Assisted Extraction.

Byproducts from artichoke represent the majority of the mass collected from the plant and constitute an interesting source of bioactive compounds such as inositols and caffeoylquinic acids. In this work, a microwave assisted extraction (MAE) methodology was developed for the simultaneous extraction of these compounds from artichoke stalks, leaves, receptacles and external bracts. Optimal MAE conditions to maximize the extraction of these bioactives and the antioxidant activity were 97 °C, 3 min, ethanol:water (50:50, v/v). Moreover, a GC-MS methodology was also developed for the simultaneous determination of these compounds in a single run; optimal derivatization conditions were achieved using hexamethyldisilazane and N,O-bis(trimethylsilyl)trifluoroacetamide with 1% trimethylchlorosilane. Artichoke receptacle extracts were the richest in caffeoylquinic acids (28-35 mg g-1 dry sample), followed by the bracts (9-18 mg g-1 dry sample), while those from leaves showed the highest concentrations of inositols (up to 15 mg g-1 dry sample). Receptacle extracts also had the highest antioxidant activity (123 mg TE g-1 dry sample) and the greatest concentration of total phenolic compounds (47 mg GAE g-1 dry sample). Therefore, the developed methodology could be considered as a valuable procedure to obtain and characterize bioactive ingredients with industrial interest from artichoke byproducts, opening new routes of revalorization of artichoke agro-industrial residues.

Short echo-time Magnetic Resonance Spectroscopy in ALS, simultaneous quantification of glutamate and GABA at 3 T.

Cortical hyperexcitability has been found in early Amyotrophic Lateral Sclerosis (ALS) and is hypothesized to be a key factor in pathogenesis. The current pilot study aimed to investigate cortical inhibitory/excitatory balance in ALS using short-echo Magnetic Resonance Spectroscopy (MRS). Patients suffering from ALS were scanned on a 3 T Trio Siemens MR scanner using Spin Echo Full Intensity Acquired Localized (SPECIAL) Magnetic Resonance Spectroscopy in primary motor cortex and the occipital lobe. Data was compared to a group of healthy subjects. Nine patients completed the scan. MRS data was of an excellent quality allowing for quantification of a range of metabolites of interest in ALS. In motor cortex, patients had Glutamate/GABA and GABA/Cr- ratios comparable to healthy subjects. However, Glutamate/Cr (p = 0.002) and the neuronal marker N-acetyl-aspartate (NAA/Cr) (p = 0.034) were low, possibly due to grey-matter atrophy, whereas Glutathione/Cr (p = 0.04) was elevated. In patients, NAA levels correlated significantly with both hand strength (p = 0.027) and disease severity (p = 0.016). In summary SPECIAL MRS at 3 T allows of reliable quantification of a range of metabolites of interest in ALS, including both excitatory and inhibitory neurotransmitters. The method is a promising new technique as a biomarker for future studies on ALS pathophysiology and monitoring of disease progression.

An enzymatic assay for quantification of inositol in human term placental tissue.

A modified sensitive, cheap and simple enzymatic assay method is described for the quantitation of inositol (6-carbon polyol) in human placental tissue. Water-soluble and total (water-soluble and lipid-bound) inositol isomers were extracted and quantified using a 96-well adaptation of the Megazyme® assay. This assay specifically recognized myo-inositol (predominant isomer), d-chiro-, epi-, and allo-inositols, but not scyllo-inositol, glucose or fucose. In term placenta, water-soluble and total inositol contents were high [489 (±58) and 635 (±69) µg/g respectively], and reliably quantified with good reproducibility. This modified assay could facilitate placental inositol biology research, particularly pertinent now with interest in myo-inositol supplementation for gestational diabetes (GDM) prevention.

GC-MS analysis of D-pinitol in carob: Syrup and fruit (flesh and seed).

D-pinitol (3-O-methyl-D-chiro-inositol) is a well-known bioactive compound with anti-diabetic and anti-oxidant biological functions. A gas chromatography-mass spectrometry (GC-MS) method was developed for its quantitation in carob syrup, flesh and seed samples originated from Cyprus. The analysis was performed after derivatization of carbohydrates and polyols into trimethylsilyl ether derivatives. D-pinitol was determined in 13 carob syrup samples, in concentrations ranging 65.71 ±â€¯4.60 - 77.72 ±â€¯5.44 mg/g (mean: 68.58 ±â€¯4.80 mg/g, n = 13). In two commercial samples, it was determined in relative medium-low concentrations (21.96 ±â€¯1.54 and 44.71 ±â€¯3.13 mg/g), revealing possible adulteration; however, this needs further investigation. Similarly, it was determined in high concentrations in carob flesh samples, in concentrations ranging 53.20 ±â€¯3.72 - 54.58 ±â€¯3.82 mg/g (mean: 53.81 ±â€¯3.76 mg/g, n = 3). On the other hand, seed samples proved very poor in D-pinitol (

Evaluation of Cycloferin Supplement on Health Parameters in Experimentally Induced Diabetic Rats with and Without Exogenous Insulin.

Cycloferin is an extract of the chemicals from the Cyclopia species, which grows only in small areas in the southwest and southeast of South Africa and has been consumed traditionally as a nourishing tea to treat numerous health issues and illnesses. Previous studies report that some of the active compounds in Cycloferin, such as pinitol (a modified sugar) and mangiferin (a glucoside), may reduce blood sugar levels and therefore may be used as a treatment for diabetes. Mangiferin, in particular, has been shown to stimulate carbohydrate oxidation and alleviate some effects of insulin resistance and hyperglycemia. Other active components of Cycloferin include flavones, isoflavones, coumestans, luteolin, 4-hydroxycinnamic acid, polyphenols, and xanthones. These active compounds are antioxidants, which can enhance glucose breakdown, lower blood lipids, and reduce the number of highly reactive compounds known as free radicals, which can alter cellular structure and function when present in large amounts. In this study, we explored the ameliorative effects of Cycloferin by treating streptozotocin- (STZ) injected rats with Cycloferin and evaluating its long-term and short-term effect on blood glucose levels and kidney and liver conditions of the diabetic-rendered rats. Our results demonstrated the ability of Cycloferin to both lower the blood glucose levels and reduce evidence of damage in kidney and liver in diabetic rats with and without exogenous insulin treatment for partial control of diabetic state.

Extraction and characterization of low molecular weight bioactive carbohydrates from mung bean (Vigna radiata).

Due to the great interest in obtaining natural bioactive carbohydrates to be used as functional ingredients, a selective microwave assisted extraction (MAE) method was optimized to ensure the exhaustive extraction of inositols and α-galactooligosaccharides (α-GOS) from mung bean. Thereafter, a comprehensive characterization of these compounds was carried out by gas chromatography coupled to mass spectrometry (GC-MS). Apart from free inositols and α-GOS, several glycosyl-methyl-scyllo-inositols and glycosyl-inositols were detected for the first time in this legume. Under optimized MAE conditions (0.5 g dry sample, 2 cycles of 3 min, 50 °C, 10 mL 50:50 ethanol:water, v:v), bioactive carbohydrates yields were similar to those found using solid-liquid extraction (SLE), but with shorter analytical times. Concentrations of bioactive carbohydrates in MAE extracts from samples of different geographical origins ranged between 74.1 and 104.2 mg.g-1 dry sample. MAE was proved a good alternative to SLE to obtain extracts enriched in bioactive carbohydrates.

Electroacupuncture ameliorate learning and memory by improving N-acetylaspartate and glutamate metabolism in APP/PS1 mice.

OBJECTIVE: To explore the precise mechanism of electroacupuncture (EA) to delay cognitive impairment in Alzheimer disease. METHODS: N-Acetylaspartate (NAA), glutamate (Glu) and myoinositol (mI) metabolism were measured by magnetic resonance spectroscopy, learning and memory of APP/PS1 mouse was evaluated by the Morris water maze test and the step-down avoidance test, neuron survival number and neuronal structure in the hippocampus were observed by Nissl staining, and BDNF and phosphorylated TrkB detected by Western blot. RESULTS: EA at DU20 acupuncture significantly improve learning and memory in behavioral tests, up-regulate NAA, Glu and mI metabolism, increase the surviving neurons in hippocampus, and promote the expression of BDNF and TrkB in the APP/PS1 transgenic mice. CONCLUSION: These findings suggested that EA is a potential therapeutic for ameliorate cognitive dysfunction, and it might be due to EA could improve NAA and Glu metabolism by upregulation of BDNF in APP/PS1 mice.

Intralipid/Heparin Infusion Alters Brain Metabolites Assessed With 1H-MRS Spectroscopy in Young Healthy Men.

Context: We previously demonstrated that insulin infusion altered metabolite concentrations in cerebral tissues assessed with proton magnetic resonance spectroscopy (1H-MRS) in young subjects with high insulin sensitivity, but not in those with low insulin sensitivity. Fat overload is an important factor leading to insulin resistance. Objective: The purpose of the current study was to examine the effect of elevated circulating free fatty acid (FFA) levels on metabolites in cerebral tissues assessed with 1H-MRS. Design: The study group comprised 10 young, healthy male subjects. 1H-MRS was performed at baseline and after 4-hour Intralipid (Fresenius Kabi)/heparin or saline infusions administered in random order. Voxels were positioned in the left frontal lobe, left temporal lobe, and hippocampus. The ratios of N-acetylaspartate (NAA), choline (Cho)-containing compounds, myo-inositol (mI), and glutamate/glutamine/γ-aminobutyric acid complex (Glx) to creatine (Cr) and nonsuppressed water signal were determined. Results: Intralipid/heparin infusion resulted in a significant increase in circulating FFAs (P < 0.0001). Significant changes in brain neurometabolite concentrations in response to Intralipid/heparin infusion were increases in frontal mI/Cr (P = 0.041) and mI/H2O (P = 0.037), decreases in frontal and hippocampal Glx/Cr (P = 0.018 and P = 0.015, respectively) and Glx/H2O (P = 0.03 and P = 0.067, respectively), and a decrease in hippocampal NAA/Cr (P = 0.007) and NAA/H2O (P = 0.019). No changes in neurometabolites were observed during the saline infusion. Conclusions: Acute circulating FFA elevation influenced cerebral metabolites in healthy humans and lipid-induced insulin resistance could be partly responsible for these effects.

NMR-based approach reveals seasonal metabolic changes in mate (Ilex paraguariensis A. St.-Hil.).

Ilex paraguariensis (mate) is a species native to South America and is widely consumed in countries such Argentina, Uruguay, Paraguay, and Brazil. Mate consumption is associated with several phytotherapeutic functions, in addition to its cultural and regional importance. However, the harvest period can affect the properties of the mate, due to variations in the constituent proportions, as a consequence of seasonal changes. In this work, we employed nuclear magnetic resonance and chemometrics to evaluate the chemical variations in leaf extracts of I. paraguariensis over the four seasons of the year. We found significant changes in the levels of glucose, myo-inositol, caffeine, theobromine, and fatty acids. These changes can be related to resource allocation for the flowering period, or to responses to environmental stresses, such as temperature.

Electroacupuncture ameliorate learning and memory by improving N -acetylaspartate and glutamate metabolism in APP/PS1 mice

OBJECTIVE: To explore the precise mechanism of electroacupuncture (EA) to delay cognitive impairment in Alzheimer disease. Methods N -Acetylaspartate (NAA), glutamate (Glu) and myoinositol (mI) metabolism were measured by magnetic resonance spectroscopy, learning and memory of APP/PS1 mouse was evaluated by the Morris water maze test and the step-down avoidance test, neuron survival number and neuronal structure in the hippocampus were observed by Nissl staining, and BDNF and phosphorylated TrkB detected by Western blot. RESULTS: EA at DU20 acupuncture significantly improve learning and memory in behavioral tests, up-regulate NAA, Glu and mI metabolism, increase the surviving neurons in hippocampus, and promote the expression of BDNF and TrkB in the APP/PS1 transgenic mice. CONCLUSION: These findings suggested that EA is a potential therapeutic for ameliorate cognitive dysfunction, and it might be due to EA could improve NAA and Glu metabolism by upregulation of BDNF in APP/PS1 mice.

A Targeted Metabolomics MRM-MS Study on Identifying Potential Hypertension Biomarkers in Human Plasma and Evaluating Acupuncture Effects.

The critical role of metabolic abnormality in hypertension is increasingly recognized, but its biomarkers are not clearly identified. In this study, 47 chemical compounds recorded by literature were employed as target metabolites of essential hypertension (EH). We detected their content in the plasma of EH patients and healthy subjects by using the Multiple Reaction Monitoring-Mass Spectrometry (MRM-MS). After screening the most altered compounds, acupuncture was used to treat patients for 3 months and these plasma metabolites were tested again. The results showed that oleic acid (OA) and myoinositol (MI) were the most important differential metabolites between the hypertensive plasma and the healthy plasma. They were also closely correlated with 24-hour blood pressure and nocturnal dipping. Moreover, plasma OA and MI could be restored to normal levels by acupuncture, accompanying with reduction of 24-hour systolic and diastolic blood pressure [from 145.10 ± 9.28 mm Hg to 140.70 ± 9.59 mm Hg (P < 0.0001), and 88.35 ± 7.92 mm Hg to 85.86 ± 7.95 mm Hg (P = 0.0024), respectively] and improvement of circadian blood pressure rhythm. This study demonstrated that plasma OA and MI were potential hypertension biomarkers and they could be used to preliminarily assess the treating effects such as acupuncture.

Abnormalities in myo-inositol metabolism associated with type 2 diabetes in mice fed a high-fat diet: benefits of a dietary myo-inositol supplementation.

We previously reported that a chronic supplementation with myo-inositol (MI) improved insulin sensitivity and reduced fat accretion in mice. We then tested the potency of such dietary intervention in the prevention of insulin resistance in C57BL/6 male mouse fed a high-fat diet (HFD). In addition, some abnormalities in inositol metabolism were reported to be associated with insulin resistance in several animal and human studies. We then investigated the presence of such anomalies (i.e. inosituria and an inositol intra-tissue depletion) in this diet-induced obesity (DIO) mouse model, as well as the potential benefit of a MI supplementation for inositol intra-tissue deficiency correction. HFD (60 % energy from fat) feeding was associated with inosituria and inositol intra-tissue depletion in the liver and kidneys. MI supplementation (0·58 mg/g per d) restored inositol pools in kidneys (partially) and liver (fully). HFD feeding for 4 months induced ectopic lipid redistribution to liver and muscles, fasting hyperglycaemia and hyperinsulinaemia, insulin resistance and obesity that were not prevented by MI supplementation, despite a significant improvement in insulin sensitivity parameter K insulin tolerance test and a reduction in white adipose tissue (WAT) mass ( - 17 %, P< 0·05). MI supplementation significantly reduced fatty acid synthase activity in epididymal WAT, which might explain its beneficial, but modest, effect on WAT accretion in HFD-fed mice. Finally, we found some abnormalities in inositol metabolism in association with a diabetic phenotype (i.e. insulin resistance and fasting hyperglycaemia) in a DIO mouse model. Dietary MI supplementation was efficient in the prevention of inositol intra-tissue depletion, but did not prevent insulin resistance or obesity efficiently in this mouse model.

Bacteriological, biochemical, and immunological properties of colostrum and mature milk from mothers of extremely preterm infants.

OBJECTIVES: The objective of this work was to elucidate the influence of extremely premature birth (gestational age 24-27 weeks) on the microbiological, biochemical, and immunological composition of colostrum and mature milk. METHODS: A total of 17 colostrum and 34 mature milk samples were provided by the 22 mothers of extremely preterms who participated in this study. Bacterial diversity was assessed by culture-based methods, whereas the concentration of lactose, glucose, and myo-inositol was determined by a gas chromatography procedure. Finally, the concentrations of a wide spectrum of cytokines, chemokines, growth factors, and immunoglobulins were measured using a multiplex system. RESULTS: Bacteria were present in a small percentage of the colostrum and milk samples. Staphylococci, streptococci, and lactobacilli were the main bacterial groups isolated from colostrum, and they could be also isolated, together with enterococci and enterobacteria, from some mature milk samples. The colostrum concentrations of lactose and glucose were significantly lower than those found in mature milk, whereas the contrary was observed in relation to myo-inositol. The concentrations of most cytokines and immunoglobulins in colostrum were higher than in mature milk, and the differences were significant for immunoglobulin G3, immunoglobulin G4, interleukin (IL)-6, interferon-γ, interleukin-4 (IL-4), IL-13, IL-17, macrophage-monocyte chemoattractant protein-1 and macrophage inflammatory protein-1ß. CONCLUSIONS: The bacteriological, biochemical, and immunological content of colostrum and mature milk from mothers of extremely preterm infants is particularly valuable for such infants. Efforts have to be made to try that preterm neonates receive milk from their own mothers or from donors matching, as much as possible, the gestational age of the preterm.

Determination of free and total myo-inositol in infant formula and adult/pediatric nutritional formula by high- performance anion exchange chromatography with pulsed amperometric detection, including a novel total extraction using microwave-assisted acid hydrolysis and enzymatic treatment: first action 2012.12.

After an assessment of data generated from a single-laboratory validation study published in J. AOAC Int. 95, 1469-1478 (2012), a method for determining total myo-inositol in infant formula and adult/ pediatric nutritional formula by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), including extraction by using microwave-assisted acid hydrolysis and enzymatic treatment was presented for consideration by AOAC during the AOAC Annual Meeting held in Las Vegas, NV, from September 30 to October 3, 2012. The Expert Review Panel on Infant Formula and Adult Nutritionals concluded that the method met the criteria set by the standard method performance requirements (SMPRs) for the determination of free myo-inositol and approved the method as AOAC Official First Action. The method also determines total myo-inositol, but includes bound sources that the SMPRs exclude. The method involves using HPAEC-PAD for free myo-inositol and a total myo-inositol determination by two different techniques. The first technique uses the conventional acid hydrolysis with 6 h incubation in an autoclave. The second uses a microwave-assisted acid hydrolysis with enzymatic treatment that decreases the extraction time.

Compositional requirements of follow-up formula for use in infancy: recommendations of an international expert group coordinated by the Early Nutrition Academy.

The follow-up formula (FUF) standard of Codex Alimentarius adopted in 1987 does not correspond to the recently updated Codex infant formula (IF) standard and current scientific knowledge. New Zealand proposed a revision of the FUF Codex standard and asked the non-profit Early Nutrition Academy, in collaboration with the Federation of International Societies for Paediatric Gastroenterology, Hepatology, and Nutrition (FISPGHAN), for a consultation with paediatric nutrition experts to provide scientific guidance. This global expert group strongly supports breastfeeding. FUF are considered dispensable because IF can substitute for breastfeeding throughout infancy, but FUF are widely used and thus the outdated current FUF standard should be revised. Like IF, FUF serve as breast milk substitutes; hence their marketing should respect appropriate standards. The compositional requirements for FUF for infants from 6 months onwards presented here were unanimously agreed upon. For some nutrients, the compositional requirements for FUF differ from those of IF due to differing needs with infant maturation as well as a rising contribution of an increasingly diversified diet with advancing age. FUF should be fed with adequate complementary feeding that is also appropriate for partially breastfed infants. FUF could be fed also after the age of 1 year without safety concerns, but different compositional requirements should be applied for optimal, age-adapted milk-based formulations for young children used only after the age of 1 year. This has not been considered as part of this review and should be the subject of further consideration.

Determination of myo-inositol (free and bound as phosphatidylinositol) in infant formula and adult nutritionals by liquid chromatography/pulsed amperometry with column switching: first action 2011.18.

Myo-inositol is a 6-carbon cyclic polyalcohol also known as meso-inositol, meat sugar, inosite, and i-inositol. It occurs in nature in both free (myo-inositol) and bound (inositol phosphates and phosphatidylinositol) forms. For the determination of free myo-inositol, samples are mixed with dilute hydrochloric acid to extract myo-inositol and precipitate proteins, diluted with water, and filtered. For the determination of myo-inositol bound as phosphatidylinositol, samples are extracted with chloroform, isolated from other fats with silica SPE cartridges, and hydrolyzed with concentrated acid to free myo-inositol. Prepared samples are first injected onto a Dionex CarboPac PA1 column, which separates myo-inositol from other late-eluting carbohydrates. After column switching, myo-inositol is further separated on a CarboPac MA1 column using a 0.12% sodium hydroxide mobile phase; strongly retained carbohydrates are eluted from the PA1 column with a 3% sodium hydroxide mobile phase. Eluant from the CarboPac MA1 analytical column passes through an electrochemical detector cell where myo-inositol is detected by pulsed amperometry using a gold electrode. The method showed appropriate performance characteristics versus selected established standard method performance requirement parameters for the determination of myo-inositol: linear response; repeatability (RSDr) of 2%; and intermediate precision (RSDir) of 2.5%. Instrument LOD and LOQ were 0.0004 and 0.0013 mg/100 mL, respectively, and correspond to a free myo-inositol quantitation limit of 0.026 mg/100 g and a phosphatidylinositol quantitation limit of 0.016 mg/100 g. Correlation with the reference microbiological assay was good. The proposed method has been accepted by the Expert Review Panel as an AOAC First Action Method, suitable for the routine determination of myo-inositol in infant formula and adult nutritionals.

Gas chromatography-mass spectrometry analysis of 13C labeling in sugars for metabolic flux analysis.

Metabolic flux analysis, using 13C labeled substrates, has become a powerful methodology for quantifying intracellular fluxes. Most often, analysis is restricted to nuclear magnetic resonance or mass spectrometry measurement of 13C label incorporation into protein amino acids. However, amino acid isotopomer distribution insufficiently covers the entire network of central metabolism, especially in plant cells with highly compartmented metabolism, and analysis of other metabolites is required. Analysis of label in saccharides provides complementary data to better define fluxes around hexose, pentose, and triose phosphate pools. Here, we propose a gas chromatography-mass spectrometry (GC-MS) method to analyze 13C labeling in glucose and fructose moieties of sucrose, free glucose, fructose, maltose, inositol, and starch. Our results show that saccharide labeling for isotopomer quantification is better analyzed by chemical ionization than by electron ionization. The structure of the generated fragments was simulated and validated using labeled standards. The method is illustrated by analysis of saccharides extracted from developing rapeseed (Brassica napus L.) embryos. It is shown that glucose 6-phosphate isomerase and plastidial glucose 6-phosphate transport reactions are not at equilibrium, and light is shed on the pathways leading to fructose, maltose, and inositol synthesis.

Quantitative analysis of myo-inositol in urine, blood and nutritional supplements by high-performance liquid chromatography tandem mass spectrometry.

Myo-inositol plays key physiological functions, necessitating development of methodology for quantification in biological matrices. Limitations of current mass spectrometry-based approaches include the need for a derivatisation step and/or sample clean-up. In addition, co-elution of glucose may cause ion suppression of myo-inositol signals, for example in blood or urine samples. We describe an HPLC-MS/MS method using a lead-form resin based column online to a triple quadrupole tandem mass spectrometer, which requires minimum sample preparation and no derivatisation. This method allows separation and selective detection of myo-inositol from other inositol stereoisomers. Importantly, inositol was also separated from hexose monosaccharides of the same molecular weight, including glucose, galactose, mannose and fructose. The inter- and intra-assay variability was determined for standard solutions and urine with inter-assay coefficient of variation (CV) of 1.1% and 3.5% respectively, while intra-assay CV was 2.3% and 3.6%. Urine and blood samples from normal individuals were analysed.

Determination of free inositols and other low molecular weight carbohydrates in vegetables.

Different low molecular weight carbohydrates including saccharides, polyalcohols, sugar acids, and glycosides have been identified and quantified in different edible vegetables from Asteraceae, Amarantaceae, Amarylidaceae, Brassicaceae, Dioscoreaceae, and Solanaceae families by gas chromatography-mass spectrometry. Apart from glucose, fructose, and sucrose, other saccharides such as sedoheptulose in chicory, spinach, cabbage, purple yam, eggplant, radish, and oak leaf lettuce, rutinose in eggplant skin, and a glycosyl-inositol in spinach have been identified. chiro-Inositol was found in all vegetables of the Asteraceae family (3.1-32.6 mg 100 g(-1)), whereas scyllo-inositol was detected in those of purple yam, eggplant, artichoke, chicory, escarole, and endive (traces-23.2 mg 100 g(-1)). α-Galactosides, kestose, glucaric acid, and glycosyl-glycerols were also identified and quantified in some of the analyzed vegetables. Considering the bioactivity of most of these compounds, mainly chicory leaves, artichokes, lettuces, and purple yam could constitute beneficial sources for human health.