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Alpha-linolenic acid (ALA) and linoleic acid (LA), abundant in chia seed oil, are useful polyunsaturated fatty acids (PUFA) with numerous health benefits. The objectives of the present study were to explore the optimum extraction condition of chia seed oil and the possibilities of direct analysis of ALA and LA in chia seed oil by reversed-phase high-performance liquid chromatography with ultraviolet detection (RP-HPLC-UV). The optimized chia seed oil extraction condition was set by the usage of Soxhlet extrator with hexane as a solvent, with the solvent to solid ratio of 8 and the extraction time of 8 h. Prior to HPLC-UV analysis, the oil was saponified in order to get the free fatty acids for detection. The results showed that the proposed HPLC-UV method allowed the quantification of ALA and LA in chia seed oil. The method was simple, rapid (within 18 min) and sensitive (limit of detection 0.006 mg/mL for ALA and 0.02 mg/mL for LA) and precise (RSD ≤ 2%). Thus, the proposed experimental designs were shown to offer considerable advantages over traditional derivatization approaches in the ALA and LA analyses. [ABSTRACT FROM AUTHOR]

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Abstract: A simple procedure is described for the simultaneous extraction and determination of betulin and betulinic acid in white birch bark. The extraction was checked using different solvents: dichloromethane, ethyl acetate, acetone, chloroform, methanol and 95% ethanol (aqueous solution, v/v). It was found 95% ethanol was a good extraction solvent that allowed extraction of triterpenoid with a highest content. Separation was achieved on a reversed phase C18 column with acetonitrile–water 86:14 (v/v). Detection was accomplished with UV detection at λ =210nm. Using this method, the bioactive triterpenoid in white birch bark were simultaneously determined. Significant variations in the content of betulin and betulinic acid in white birch bark growing in different locations of China were also observed. [Copyright &y& Elsevier]

A simple and fast high-performance liquid chromatography (HPLC) fingerprint method combining reference standard extract for the identification of bilberry extract was developed and validated. Six batches of bilberry extract collected from different manufactures were used to establish the HPLC fingerprint. Other berry extracts—such as blueberry extracts, mulberry extracts, cranberry extracts, and black rice extracts—were also analyzed for their HPLC chromatograms. The fingerprints of five batches of bilberry extract showed high similarities, while one batch was distinguished from others. Additionally, the content of anthocyanin Cyanidin-3-O-glucoside (Cy-3-glc) in each berry extract was analyzed and compared. The results indicate that this HPLC fingerprint method, combining reference standard extracts, could be used for the authentication and quality control of bilberry extracts. [ABSTRACT FROM AUTHOR]

Abstract: The solubilities of trans-resveratrol in methanol, ethanol, 1-propanol, 2- propanol, 1-butanol, 1-pentanol, 1-hexanol, ethyl acetate, tetrahydrofuran, acetone, and water (pH 6.0) solvents were measured at T =(278.2, 288.2, 298.2, 308.2, and 318.2)K. The solubilities of trans-resveratrol in selected solvents increase with temperature, but decrease with increasing the number of carbon in alcohol solvents. The experimental data were correlated using a thermodynamic equation. [Copyright &y& Elsevier]

A method of using semi-preparative HPLC coupling with a post-HPLC flash freezing treatment to separate platycosides from Platycodi Radix is developed. Nine platycosides including unstable acetyl platycosides were separated from Platycodi Radix by semi-preparative HPLC. Separation variables of flow rate and loading amount of sample were linearly scaled up from analytical HPLC to semi-preparative HPLC. Variables of semi-preparative HPLC separation including flow rate and loading amount of sample were calculated as 29.8 mL/min and 297.7 mg, respectively. Under the optimized conditions of separation, nine platycosides were simultaneously separated on semi-preparative scale within 1 h. Separation resolutions of the peaks of platycosides were all above 0.85, of which seven platycosides were separated with resolutions above 1.00. With regards to sample pretreatment before chromatography separation, we propose a post-HPLC treatment to the unstable compounds. A post-HPLC treatment by using liquid nitrogen to flash freeze the eluent fractions from semi-preparative HPLC was used to stop the unstable platycosides transformation. By freezing treatment, the pure unstable acetyl platycosides were obtained without transformation. This was the first time that unstable acetyl platycosides were simultaneously separated by preparative HPLC. This method is fast and efficient to separate platycosides from Platycodi Radix, especially for purifying unstable platycosides. [ABSTRACT FROM AUTHOR]