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Analytical Chemistry Aug 2015A fast, sensitive, and selective ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method that is able to quantify geochemical...
A fast, sensitive, and selective ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method that is able to quantify geochemical biomarkers in sediment is described. A pool of 10 sterols, which can be used as biomarkers of autochthonous (cholesterol, cholestanol, brassicasterol, ergosterol), allochthonous (stigmasterol, β-sitosterol, campesterol, and stigmastanol) and anthropogenic (coprostanol and epicoprostanol) organic matter (OM), and three triterpenols (lupeol, α-amyrin, and β-amyrin) were chosen as the analytes. The method showed excellent analytical parameters, and, compared with the traditional GC-MS methods that are commonly applied for the analysis of sterols, this method requires no sample cleanup or derivatization and presents improved values for the LOD and LOQ. UHPLC can separate the diastereoisomers (epicoprostanol, coprostanol, and cholestanol) and the isomers (lupeol, α-amyrin, and β-amyrin). The method was successfully applied for the quantification of the biomarkers, and thus, it was applied to assess the OM sources and the impacts of anthropogenic activities in sediments from different environments, such as Antarctica and other Brazilian systems (Continental Shelf, São Sebastião Channel, and Santos Estuary). Unique profiles of the biomarkers were observed for the contrasting environments, and β-amyrin and cholesterol were more predominant in the Santos Estuary and Antarctica samples, respectively. The sterol ratios indicated a higher level of sewage contamination in the Santos Estuary.
Topics: Chromatography, Liquid; Environmental Monitoring; Geologic Sediments; Limit of Detection; Sterols; Tandem Mass Spectrometry; Time Factors; Triterpenes
PubMed: 26132310
DOI: 10.1021/acs.analchem.5b01517 -
Food Chemistry Nov 2016A novel method for the measurement of total phytosterols in fortified food was developed and tested using gas chromatography with flame ionization detection. Unlike...
A novel method for the measurement of total phytosterols in fortified food was developed and tested using gas chromatography with flame ionization detection. Unlike existing methods, this technique is capable of simultaneously extracting sterols during saponification thus significantly reducing extraction time and cost. The rapid method is suitable for sterol determination in a range of complex fortified foods including milk, cheese, fat spreads, oils and meat. The main enhancements of this new method include accuracy and precision, robustness, cost effectiveness and labour/time efficiencies. To achieve these advantages, quantification and the critical aspects of saponification were investigated and optimised. The final method demonstrated spiked recoveries in multiple matrices at 85-110% with a relative standard deviation of 1.9% and measurement uncertainty value of 10%.
Topics: Animals; Chemical Fractionation; Flame Ionization; Food, Fortified; Meat; Milk; Phytosterols; Plant Oils
PubMed: 27283669
DOI: 10.1016/j.foodchem.2016.05.104 -
Bioscience Reports Oct 2018This short article provides a comment on the recent article by Tauriainen et al. [ (2018) , BSR20171274 https://doi.org/10.1042/BSR20171274].
This short article provides a comment on the recent article by Tauriainen et al. [ (2018) , BSR20171274 https://doi.org/10.1042/BSR20171274].
Topics: Bile; Humans; Liver; Non-alcoholic Fatty Liver Disease; Obesity; Sitosterols
PubMed: 30287500
DOI: 10.1042/BSR20180505 -
Environmental Research Mar 2022The stress on the environment is increasing as the human population living on it increases. Water eutrophication, a leading cause of impairment of many freshwater and...
The stress on the environment is increasing as the human population living on it increases. Water eutrophication, a leading cause of impairment of many freshwater and coastal marine ecosystems in the world, is a typical consequence of anthropogenic pressure on the environment. The Baltic Sea represents an excellent example of eutrophication-related massive bottom water deoxygenation since 1950s, when the nutrient inputs derived from agricultural fertilisers and wastewater discharges increased significantly. Faecal lipids (β-stanols) represent a tool to estimate qualitatively anthropogenic sewage pollution in the environment. The present study shows that a ratio to evaluate sewage pollution based on faecal β-stanols preserved in modern sediments reflects the eutrophication status of the Baltic Sea and rivers from its catchment area, as well as the nutrient inputs in the central Baltic Sea since 1860. A second ratio, which allows differentiating between livestock breed and human faecal matter, reflects human population growth in the Baltic Sea Eastern European countries since 1860, and more specifically in St. Petersburg. Sedimentary faecal biomarkers are thus reliable indicators for both population growth and anthropogenic sewage pollution in the Baltic Sea, and may thus be useful to evaluate the past and present status of this environment.
Topics: Ecosystem; Eutrophication; Humans; Lipids; Oceans and Seas; Population Growth; Sewage
PubMed: 34743904
DOI: 10.1016/j.envres.2021.112305 -
Analytical Chemistry Jul 2020Mass spectrometry (MS) in hyphenated techniques is widely accepted as the gold standard quantitative tool in life sciences. However, MS possesses intrinsic analytical...
Mass spectrometry (MS) in hyphenated techniques is widely accepted as the gold standard quantitative tool in life sciences. However, MS possesses intrinsic analytical capabilities that allow it to be a stand-alone quantitative technique, particularly with current technological advancements. MS has a great potential for simplifying quantitative analysis without the need for tedious chromatographic separation. Its selectivity relies on multistage MS analysis (MS), including tandem mass spectrometry (MS/MS), as well as the ever-growing advancements of high-resolution MS instruments. This perspective describes various analytical platforms that utilize MS as a stand-alone quantitative technique, namely, flow injection analysis (FIA), matrix assisted laser desorption ionization (MALDI), including MALDI-MS imaging and ion mobility, particularly high-field asymmetric waveform ion mobility spectrometry (FAIMS). When MS alone is not capable of providing reliable quantitative data, instead of conventional liquid chromatography (LC)-MS, the use of a guard column (i.e., fast chromatography) may be sufficient for quantification. Although the omission of chromatographic separation simplifies the analytical process, extra procedures may be needed during sample preparation and clean-up to address the issue of matrix effects. The discussion of this manuscript focuses on key parameters underlying the uniqueness of each technique for its application in quantitative analysis without the need for a chromatographic separation. In addition, the potential for each analytical strategy and its challenges are discussed as well as improvements needed to render them as mainstream quantitative analytical tools. Overcoming the hurdles for fully validating a quantitative method will allow MS alone to eventually become an indispensable quantitative tool for clinical and toxicological studies.
Topics: Cholesterol; Chromatography, High Pressure Liquid; Flow Injection Analysis; Ion Mobility Spectrometry; Limit of Detection; Mass Spectrometry; Phytosterols; Sitosterols; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 32510944
DOI: 10.1021/acs.analchem.0c00877 -
Journal of Liposome Research Sep 2014Quercetin (QT) is a potential chemotherapeutic drug with low solubility that seriously limits its clinical use. The aim of this study was enhancing cellular penetration... (Comparative Study)
Comparative Study
Quercetin (QT) is a potential chemotherapeutic drug with low solubility that seriously limits its clinical use. The aim of this study was enhancing cellular penetration of QT by sterol containing solid lipid nanoparticles (SLNs) which make bilayers fluent for targeting hepatocellular carcinoma cells. Three variables including sterol type (cholesterol, stigmasterol and stigmastanol), drug and sterol content were studied in a surface response D-optimal design for preparation of QT-SLNs by emulsification solvent evaporation method. The studied responses included particle size, zeta potential, drug loading capacity and 24 h release efficiency (RE24%). Scanning electron and atomic force microscopy were used to study the morphology of QT-SLNs and their thermal behavior was studied by DSC analysis. Cytotoxicity of QT-SLNs was determined by MTT assay on HepG-2 cells and cellular uptake by fluorescence microscopy method. Optimized QT-SLNs obtained from cholesterol and QT with the ratio of 2:1 that showed particle size of 78.0 ± 7.0 nm, zeta potential of -22.7 ± 1.3 mV, drug loading efficiency of 99.9 ± 0.5% and RE24 of 56.3 ± 3.4%. IC50 of QT in cholesterol SLNs was about six and two times less than free QT and phytosterol SLNs, respectively, and caused more accumulation of QT in HepG2 cells. Blank phytosterol SLNs were toxic on cells.
Topics: Antineoplastic Agents, Phytogenic; Carcinoma, Hepatocellular; Chemistry, Pharmaceutical; Cholesterol; Hep G2 Cells; Humans; Liposomes; Liver Neoplasms; Nanoparticles; Particle Size; Quercetin; Sitosterols; Stigmasterol
PubMed: 24354715
DOI: 10.3109/08982104.2013.868476 -
European Journal of Nutrition Aug 2020Lowering of LDL cholesterol levels by plant sterols and stanols is associated with decreased risk of cardiovascular disease in humans. Plant sterols and stanols also...
PURPOSE
Lowering of LDL cholesterol levels by plant sterols and stanols is associated with decreased risk of cardiovascular disease in humans. Plant sterols and stanols also lower triacylglycerol (TG). However, it is not fully understood how reduction in TG is achieved and what the full potential of plant sterols and stanols is on whole-body metabolism. We here hypothesize that high levels of plant sterols and stanols stimulate whole-body energy expenditure, which can be attributed to changes in mitochondrial function of brown adipose tissue (BAT), skeletal muscle and liver.
METHODS
Phytosterolemic mice were fed chow diets for 32 weeks to examine whole-body weight gain. In vitro, 24-h incubation were performed in adipocytes derived from human BAT, human myotubes or HepG2 human hepatocytes using sitosterol or sitostanol. Following mitochondrial function was assessed using seahorse bioanalyzer.
RESULTS
Chow feeding in phytosterolemic mice resulted in diminished increase in body weight compared to control mice. In vitro, sitosterol or sitostanol did not change mitochondrial function in adipocytes derived from human BAT or in cultured human myotubes. Interestingly, maximal mitochondrial function in HepG2 human hepatocytes was decreased following sitosterol or sitostanol incubation, however, only when mitochondrial function was assessed in low glucose-containing medium.
CONCLUSIONS
Beneficial in vivo effects of plant sterols and stanols on lipid and lipoprotein metabolism are well recognized. Our results indicate that alterations in human mitochondrial function are apparently not involved to explain these beneficial effects.
Topics: Adipocytes, Brown; Animals; Hepatocytes; Humans; Mice; Mitochondria; Muscle Fibers, Skeletal; Phytosterols; Respiration; Sitosterols
PubMed: 31317217
DOI: 10.1007/s00394-019-02052-y -
Foods (Basel, Switzerland) May 2020Fresh pasta was formulated by replacing wheat semolina with 0, 5, 10, and 15 g/100 g () of L. leaf powder (MOLP). The samples (i.e., M0, M5, M10, and M15 as a function...
Fresh pasta was formulated by replacing wheat semolina with 0, 5, 10, and 15 g/100 g () of L. leaf powder (MOLP). The samples (i.e., M0, M5, M10, and M15 as a function of the substitution level) were cooked by boiling. The changes in the phenolic bioaccessibility and the in vitro starch digestibility were considered. On the cooked-to-optimum samples, by means of ultra-high-performance liquid chromatography-quadrupole time-of-flight (UHPLC-QTOF) mass spectrometry, 152 polyphenols were putatively annotated with the greatest content recorded for M15 pasta, being 2.19 mg/g dry matter ( < 0.05). Multivariate statistics showed that stigmastanol ferulate (VIP score = 1.22) followed by isomeric forms of kaempferol (VIP scores = 1.19) and other phenolic acids (i.e., schottenol/sitosterol ferulate and 24-methylcholestanol ferulate) were the most affected compounds through the in vitro static digestion process. The inclusion of different levels of MOLP in the recipe increased the slowly digestible starch fractions and decreased the rapidly digestible starch fractions and the starch hydrolysis index of the cooked-to-optimum samples. The present results showed that MOLP could be considered a promising ingredient in fresh pasta formulation.
PubMed: 32422925
DOI: 10.3390/foods9050628 -
The Science of the Total Environment Sep 2014A 400-year sedimentary record of the Barigui River was investigated using fecal biomarkers and nutrient distribution. The temporal variability in cholesterol,...
A 400-year sedimentary record of the Barigui River was investigated using fecal biomarkers and nutrient distribution. The temporal variability in cholesterol, cholestanol, coprostanol, epicoprostanol, stigmastanol, stigmasterol, stigmastenol, sitosterol, and campesterol between 1600 and 2011 was assessed. Anthropogenic influences, such as deforestation and fecal contamination from humans and livestock, were observed from 1840. The sterol ratios exhibit evidence of hens, horses, cows, and an unknown herbivore, which may be a capybara (Hydrochoerus hydrochaeris), from 1820 and has been observed more markedly from 1970 onward. Human fecal contamination was detected from 1840 and was observed more markedly from 1930 due to population growth. Thus, the sanitation conditions and demographic growth of Curitiba seemed to be the main factors of human sewage pollution, as the coprostanol concentration over time was strongly correlated with the population growth (r=0.71, p<0.001) although diagenetic processes have also been observed.(1.)
Topics: Brazil; Environmental Monitoring; Feces; Rivers; Sterols; Water Pollutants; Water Pollution
PubMed: 25016471
DOI: 10.1016/j.scitotenv.2014.06.104 -
Food Chemistry Apr 2017β-sitostanol esters, used as dietary complement for decreasing cholesterol absorption, have been synthesized at 28°C via direct esterification or transesterification...
β-sitostanol esters, used as dietary complement for decreasing cholesterol absorption, have been synthesized at 28°C via direct esterification or transesterification catalyzed by the versatile lipase/sterol esterase from the ascomycete fungus O. piceae. Direct esterification was conducted in biphasic isooctane: water systems containing 10mM β-sitostanol and lauric or oleic acid as acyl donors, reaching 90% esterification in 3h with the recombinant enzyme. The use of molar excesses of the free fatty acids did not improve direct esterification rate, and the enzyme did not convert one of the two fatty acids preferentially when both were simultaneously available. On the other hand, solvent-free transesterification was an extremely efficient mechanism to synthesize β-sitostanyl oleate, yielding virtually full conversion of up to 80mM β-sitostanol in 2h. This process may represent a promising green alternative to the current chemical synthesis of these esters of unquestionable nutraceutical value.
Topics: Lipase; Ophiostoma; Sitosterols; Sterol Esterase
PubMed: 27979115
DOI: 10.1016/j.foodchem.2016.11.005