Quantification of three triterpenic acids in dried rosemary using HPLC-fluorescence detection and 4-(4,5-diphenyl-1H -imidazole-2-yl)benzoyl chloride derivatization
Autor: | Junpei Mutoh, Kenichiro Nakashima, Mitsuhiro Wada, Hisahiro Kai, Yui Tojoh, Shinichi Nakamura, Koji Matsuno |
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Rok vydání: | 2018 |
Předmět: |
Biophysics
Trimethylamine 02 engineering and technology Benzoates 01 natural sciences Fluorescence chemistry.chemical_compound Benzoyl chloride Column chromatography Ursolic acid Limit of Detection Betulinic acid Oleanolic Acid Betulinic Acid Derivatization Oleanolic acid Chromatography High Pressure Liquid Detection limit Chromatography Chemistry 010401 analytical chemistry Imidazoles Temperature Reproducibility of Results 021001 nanoscience & nanotechnology Rosmarinus Triterpenes 0104 chemical sciences Chemistry (miscellaneous) Calibration Pentacyclic Triterpenes 0210 nano-technology Food Analysis |
Zdroj: | Luminescence. 34:130-132 |
ISSN: | 1522-7235 |
Popis: | Functional triterpenic acids such as ursolic acid (UA), oleanolic acid (OA) and betulinic acid (BA) are representative ingredients in rosemary that may have health benefits. UA, OA and BA in rosemary extracts were derivatized with 4-(4,5-diphenyl-1H-imidazole-2-yl)benzoyl chloride (DIB-Cl) and detected using HPLC-fluorescence (FL). Dried rosemary (50 mg) was ground, added to 3 ml of ethanol, sonicated for 40 min, then the sample solution was added to a mixture of 1% trimethylamine and 1 mM DIB-Cl in acetonitrile. The mixture was settled for 5 min at room temperature, then the DIB-triterpenic acid derivatives were separated using a Wakopak Handy ODS column (250 × 4.6 mm, 6 μm) eluted with 25 mM acetate buffer (pH 4.5)/methanol/acetonitrile (= 8:10:82 v/v/v%). The fluorescence intensity of the eluent was monitored at 365 (λex ) and 490 nm (λem ) and the maximum retention time of the derivatives was 30 min. Calibration curves constructed using rosemary extract spiked with standards showed good linearity (r ≥ 0.997) in the range 2.5-100 ng/ml. The detection limits at 3σ for internal BA, UA and OA peaks in rosemary extract were 0.2, 0.4 and 0.5 ng/ml, respectively. This method was used to quantify BA, UA and OA in commercially available dried rosemary products. |
Databáze: | OpenAIRE |
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