BCIT Citations Collection | BCIT Institutional Repository

BCIT Citations Collection

Determination of ginsenoside content in Panax ginseng C.A. Meyer and Panax quinquefolius L. root materials and finished products by high-performance liquid chromatography with ultraviolet absorbance detection
An interlaboratory study was conducted on an HPLC method with UV absorbance detection, previously validated using AOAC single-laboratory validation guidelines, for the determination of the six major ginsenosides (Rg1, Re, Rb1, Rc, Rb2, and Rd) in Panax ginseng C.A. Meyer and Panax quinquefolius L. root materials, extracts, and finished products. Fourteen participating laboratories analyzed five test materials (P. ginseng whole root, P. ginseng powdered extract, P. quinquefolius whole root, P. quinquefolius powdered extract, and P. ginseng powdered extract spiked in a matrix blank) as blind duplicates, and two test materials (P. ginseng powdered whole root tablet and P. quinquefolius powdered extract hard-filled capsule) as single samples. Due to the variability of the ginsenosides (low level concentration of Rb2 in P. quinquefolius raw materials and in P. ginseng spiked matrix blanks, and the possibility of incomplete hydrolysis of the finished products during processing), it was deemed more applicable to analyze total ginsenosides rather than individual ones. Outliers were evaluated and omitted using the Cochran's test and single and double Grubbs' tests. The reproducibility RSD (RSD(R)) for the blind duplicate samples ranged from 4.38 to 5.39%, with reproducibility Horwitz Ratio (HorRat(R)) values ranging from 1.5 to 1.9. For the single replicate samples, the data sets were evaluated solely by their repeatability HorRat (HorRat(r)), which were 2.9 and 3.5 for the capsule and tablet samples, respectively. Based on these results, the method is recommended for AOAC Official First Action for the determination of total ginsenosides in P. ginseng and P. quinquefolius root materials and powdered extracts., Peer-reviewed article, Published.
Determination of hydrastine and berberine in goldenseal raw materials, extracts, and dietary supplements by high-performance liquid chromatography with UV
A multilaboratory collaborative study was conducted on a high-performance liquid chromatographic (HPLC) method utilizing UV detection, previously validated using AOAC single-laboratory validation guidelines for determination of hydrastine and berberine in goldenseal (Hydrastis canadensis L.) raw materials, extracts, and dietary supplements at levels ranging from 0.4 to 6% (w/w). Nine collaborating laboratories determined the hydrastine and berberine content in 8 blind samples. Sample materials included powdered botanical raw materials, whole root material, and 4 finished product dietary supplements containing either goldenseal powdered root material or extract. The materials were extracted with an acidified water and acetonitrile solution. HPLC analyses of the extracts were performed on a C18 column using UV detection at 230 nm. Results for powdered root material and capsule products ranged from about 0.2% (w/w) for each alkaloid to about 4% (w/w) for each alkaloid. Liquid tincture results were approximately 4000-5000 microg/mL for each alkaloid. Reproducibility relative standard deviations (RSDR) for hydrastine ranged from 2.68 to 6.65%, with HorRat values ranging from 0.77 to 1.89. RSDR for berberine ranged from 5.66 to 7.68%, with HorRat values ranging from 1.32 to 2.12. All finished products containing goldenseal extract yielded HorRat values <2.0. Based on these results, the method is recommended for Official First Action for determination of hydrastine and berberine in goldenseal raw materials and dietary supplement finished products containing powdered goldenseal and goldenseal extract., Peer-reviewed article, Published.
Determination of phenolic constituents in echinacea raw materials and dietary supplements by HPLC-UV
A collaborative study was conducted to evaluate an HPLC method for determining phenolic compounds in Echinacea spp. raw materials, powdered extracts, and tinctures. Eleven collaborating laboratories received three practice samples representing each matrix type, phenolic reference standards, eight test samples as blind duplicates, the validated analytical method, and instructions. Test samples included two raw materials, four extracts (including one in combination with astragalus and reishi), one ethanolic tincture in combination with goldenseal, and one glycerite tincture. Each material was extracted with a 60% methanol aqueous solution, separated on a C18 column, and detected at 330 nm. Results reported by laboratories for total phenolics in Echinacea roots, aerial parts, and extracts ranged from 9.5 to 62.9 mg/g with RSDR ranging from 3.64 and 7.95% and Horwitz ratio (HorRat) values ranging from 1.06 to 2.01. Total phenolics in the ethanolic tincture ranged from 4837 to 5962 μg/mL, with an RSDR of 6.35% and a HorRat value of 1.45. The glycerite tincture showed poor interlaboratory precision with a HorRat value of 3.32, an RSDR of 21.8%, and reported total phenolic values ranging from 257 to 539 μg/mL., Peer-reviewed article, Published. Received May 4, 2016; Accepted by AP May 25, 2016.