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Background: Imbalance of bile acids (BA) homeostasis in the gastrointestinal tract can lead to chronic diarrhea or constipation when BA in the colon are in excess or low, respectively. Since both disturbances of bowel function can result from other etiologies, identifying BA imbalance is important to tailor treatment strategies. Serum concentrations of 7-alpha-hydroxy-4-cholesten-3-one (7aC4), a precursor in bile acid synthesis, reflect BA homeostasis. Here we describe a method to accurately measure serum 7aC4 and evaluate the clinical utility in patients with diarrhea or constipation phenotypes., Methods: Serum 7aC4 is measured after acetonitrile protein precipitation using C18 liquid chromatography, tandem mass spectrometry, and deuterium-labeled 7aC4 internal standard. Assay performance including linearity, precision, and accuracy was assessed using waste serum samples. The reference interval was established in healthy individuals without BA-altering conditions or medications. Clinical performance was assessed in patients with irritable bowel syndrome., Results: The method precisely and accurately measured 7aC4 in human serum from 1.4-338ng/mL with no ion suppression or interference from related 7-keto-cholesterol. Central 95th percentile reference interval was 2.5-63.2ng/mL. Lower serum 7aC4 was found in patients with constipation with sensitivity/specificity of 79%/55% compared to healthy controls. Higher 7aC4 was found in patients with bile acid diarrhea (BAD) compared to those without BAD with sensitivity/specificity of 82%/53%., Conclusions: We have developed a sensitive and precise assay for measuring the concentration of 7aC4 in serum. The assay can be used to screen for diarrhea caused by bile acid malabsorption., (Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Response surface methodology was used to optimize and obtain the optimal flash-type extraction technology of alisol B 23-acetate from Alismatis Rhizoma. With the extraction rate of alisol B 23-acetate as an indicator, single-factor test was used to investigate the effect of ethanol volume fraction, liquid-solid ratio, extraction times and extracting time on the extraction rate of alisol B 23-acetate.The results were combined with Box-Benhnken design and response surface analysis to optimize the technology parameters for extraction process of Alismatis Rhizoma and obtain the optimal flash-type extraction technology under the following conditions： ethanol volume fraction 80%, liquid-solid ratio 12∶1, extraction 4 times, 114 s/time. Flash-type extraction technology of alisol B 23-acetate by response surface methodology is stable, time-saving, efficient, and with the advantages of room temperature extraction and no component damage, so it can be used for massive production., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Ergosta-4,6,8(14),22-tetraen-3-one (ergone) isolated from Polyporus umbellatus possesses a variety of pharmacological activities in vivo and in vitro, including cytotoxic, diuretic, and immunosuppressive effect. The interaction of cerium ions (Ce(3+)) with ergone was studied by fluorescence and absorption spectroscopy. Spectra data revealed that Ce(3+) ions exhibited emission maxima around 350 nm when the excitation wavelength was fixed at 255 or 290 nm, and the fluorescence of Ce(3+) ions was quenched by the addition of ergone, indicating that a Ce(3+)-ergone complex was formed. According to the modified Benesi-Hildebrand equation, the binding constant of interaction of Ce(3+) ions with ergone was obtained at room temperature. Based on this, a sensitive spectrofluorometric method using Ce(3+) ions as a probe was applied for the identification and quantification of ergone in rat plasma, feces, and urine. The linear ranges of the calibration curves were 1.31 to 4.50 μM for plasma, 1.12-9.87 μM for feces, and 1.28-3.42 μM for urine, and the ergone recoveries were found to be 97.1 ± 0.9%, 98.2 ± 0.7% and 96.5 ± 1.4% for plasma, feces, and urine, respectively. The intraday and inter-day relative standard deviations were less than 9.7%. The proposed spectrofluorometric method is simple and rapid for the quantitative determination of ergone in rat plasma, feces, and urine, and it is affordable for most laboratories because it has few requirements and uses low cost, easy to operate equipment.

The level of 7-dehydrocholesterol (7-DHC) is elevated in tissues and fluids of Smith-Lemli-Opitz syndrome (SLOS) patients due to defective 7-DHC reductase. Although over a dozen oxysterols have been identified from 7-DHC free radical oxidation in solution, oxysterol profiles in SLOS cells and tissues have never been studied. We report here the identification and complete characterization of a novel oxysterol, 3β,5α-dihydroxycholest-7-en-6-one (DHCEO), as a biomarker for 7-DHC oxidation in fibroblasts from SLOS patients and brain tissue from a SLOS mouse model. Deuterated (d₇)-standards of 7-DHC and DHCEO were synthesized from d₇-cholesterol. The presence of DHCEO in SLOS samples was supported by chemical derivatization in the presence of d₇-DHCEO standard followed by HPLC-MS or GC-MS analysis. Quantification of cholesterol, 7-DHC, and DHCEO was carried out by isotope dilution MS with the d₇-standards. The level of DHCEO was high and correlated well with the level of 7-DHC in all samples examined (R = 0.9851). Based on our in vitro studies in two different cell lines, the mechanism of formation of DHCEO that involves 5α,6α-epoxycholest-7-en-3β-ol, a primary free radical oxidation product of 7-DHC, and 7-cholesten-3β,5α,6β-triol is proposed. In a preliminary test, a pyrimidinol antioxidant was found to effectively suppress the formation of DHCEO in SLOS fibroblasts.

Objective: To develop an HPLC method for the determination of alisol A, alisol F, alisol A 24-acetate and alisol B 23-acetate in the rhizome of Alisma orientalis., Method: The separation was performed on a Shim-Pack CLC-ODS a C18 column (6 mm x 150 mm, 5 microm) eluted with the mobile phases of acetonitrile (A)-water (B) in gradient elution. The absorbance was monitored at 210 nm. Orthogonal test was adopted to optimize the extraction conditions of the four alisols., Result: The correlation coefficients of the four alisols were higher than 0.999 and the average recoveries were 99.23%, 96.67%, 97.30% and 99.61%, respectively. All the RSDs were less than 3%., Conclusion: The validation data demonstrated that the method was accurate and repeatable, and can be used to measure the four alisols in Rhizoma Alismatis.

Unlabelled: To study the effect of S-3307 on the yield and main ingredients of Alisma plantago-aquatica., Method: The contents of 24-acetyl alisol A and the 23-acetyl alisol B in tuber were determined by HPLC., Results: The contents of 24-acetyl alisol A and the 23-acetyl alisol B as well as yield were significantly increased in all groups applied with different concentrations of S-3307 comparing with control group. The optimal concentration of S-3307 was 80 mg x kg(-1). The residues of S-3307 was detected under 0.316 8 mg x kg(-1) (detecting limit)., Conclusion: The optimal concentration of S-3307 is 80 mg x kg(-1), it reached the best result when applied 36 d after seedling.

Objective: To establish chromatographic fingerprint of Sichuan native medicinal plant Alisma plantago-aquatica by RP-HPLC for the quality control., Method: The gradient elution mode was applied in chromatographic separation, and data were analyzed by "Computer Aided Similarity Evaluation" software to compare the quality of A. plantago-aquatica samples from different habitats., Result: The HPLC chromatographic fingerprinting of A. plantago-aquatica with 26 characteristic peaks was established from 17 lots of A. plantago-aquatica samples, peak 16 and 22 were identified as 24-acetyl alisol A and 23-acetyl alisol B, respectively., Conclusion: The chromatographic fingerprinting of A. plantago-aquatica with high specificity can be used to control its quality and assure lot to lot consistency. The RP-HPLC fingerprint method is repeatable, feasible in analysis of A. plantago-aquatica.

Natural products have been used for healthcare and pharmacotherapy. Because difficulties in quality control affect their production, processing, and marketing, it is necessary to establish adequate marker compounds for their effective application. Ergosta-4,6,8(14),22-tetraen-3-one(I) was studied in the screening of the marker compounds for the standardization of Polyporus Sclerotium ([symbol: see text]), which has the advantage of easy qualitative and quantitative analysis because of its fluorescence. Its applicability in the standardization of Polyporus Sclerotium is discussed based on comparative studies of 30 crude samples of Polyporus Sclerotium and some other fungi herbs using TLC and HPLC analysis with I it as the marker compound, as well as its chemical synthesis.

Alisol B 23-acetate in Rhizoma Alismatis reaped at different time was determinated by RP-HPLC. The result indicated that the content of those reaped in April is obviously higher than those reaped from Jan. to March.

The steroids, cholest-4-ene-one and cholestane-3, 6-dion, were determined in 8 species of crude drugs of Haima and Hailong by capillary gas chromatography.

5 alpha-Cholest-8(14)-en-3 beta-ol-15-one is a potent inhibitor of cholesterol biosynthesis which has significant hypocholesterolemic activity upon oral administration to animals. Described herein are the results of experiments that indicate the presence of the 15-ketosterol in rat skin. The 15-ketosterol was, after purification by medium pressure liquid chromatography on Lichroprep RP-8 columns, thin-layer chromatography on silica gel G, and reverse phase high performance liquid chromatography, characterized by gas-liquid chromatography-mass spectrometry in the form of its trimethylsilyl ether derivative. The use of an internal standard containing both tritium and deuterium permitted the determination of the levels of the 15-ketosterol by mass fragmentography. The results of five separate analyses of portions of the skin of a male Sprague Dawley rat showed a mean value of 84.5 +/- 4.1 (SEM) ng per g. Analyses of hair samples of ten male Sprague Dawley rats indicated a mean level of 143 +/- 19 (SEM) ng per g of hair. Most (approximately 72%) of the 15-ketosterol in hair was esterified. This report constitutes the first isolation of the 15-ketosterol from animal tissues.

Described herein are the chemical syntheses of a number of deuterated derivatives of 5 alpha-cholest-8(14)-en-3 beta-ol-15-one. These include the [2,2,3 alpha,4,4,7,7,9 alpha,16,16-2H10]-, [7 alpha,9 alpha,16,16-2H4]-, [7,7,9 alpha,16,16-2H5]-, and [2,2,3 alpha,4,4-2H5]-analogs of the delta 8(14)-15-ketosterol. Also included are the syntheses of the 3 beta-acetate derivatives of the latter three deuterated analogs and of 5 alpha-cholest-8(14)-en-3 beta-ol-15-one, and 5 alpha-cholest-8(14)-en-3 alpha-ol-15-one. Low resolution mass spectral data on these compounds and on 5 alpha-cholest-8(14)-en-15-one, 5 alpha-cholest-8(14)-en-3 beta-ol-15-one, 5 alpha-cholest-8(14)-en-3 alpha-ol-15-one, 3 beta-benzoyloxy-5 alpha-cholest-8(14)-en-15-one, and the trimethylsilyl ethers of the free sterols have been presented. The results of these studies, supplemented with high resolution mass spectral data on five of these compounds, have been used to evaluate the electron impact mass spectral fragmentation of the delta 8(14)-15-ketosterols and their derivatives. Also presented herein are the results of 1H, 2H, and 13C nuclear magnetic resonance studies of 5 alpha-cholest-8(14)-en-3 beta-ol-15-one and its derivatives.

Reported herein are the chemical syntheses of 29 fatty acid esters of 5 alpha-cholest-8(14)-en-3 beta-ol-15-one. These compounds were characterized by the results of ultraviolet, 1H nuclear magnetic resonance, and mass spectral studies.

The first natural occurrence of 19-norcholestenone is reported, together with 17 sterols and one other delta 4-3-ketone in the extracts of the Californian gorgonian, Muricea californica (Aurivillius). Six additional demethyl sterols and five additional 4-monomethyl sterols which remain unidentified were also detected. Lipid extracts of M. californica from a winter and summer collection were split by various chromatographic methods into free sterol, steryl ester, and steryl conjugate fractions. Sterol compositions (determined by CG and CG-MS) of each fraction, subsequent to hydrolysis, are tabulated and discussed with respect to plausible origins of observed variations. The possible relationship of the Muricea 19-nor-steroidal ketone to other naturally occurring 19-nor-steroids is discussed.