5. AOACSPDSMethods-2018AwardsV3

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method (under the recommendation of AOAC INTERNATIONAL) was used to determine LOD and LOQ of select nonvolatile ginger constituents. Data set from seven replications of blank matrix (prepared separately) from galangal root was used. LOD is defined as the sum of mean response and three times the standard deviation. LOQ is defined as the sum of mean response and 10 times the standard deviation. The instrument’s limits (mg/mL) are divided by the sample concentration to convert to a % w/w basis. ( e ) Accuracy.— To demonstrate method accuracy, galangal root (considered as the “placebo” of ginger rhizome) and the excipient blend (considered as the “placebo” of tablet and capsule dietary supplements) were spiked with nonvolatile ginger constituent reference material solutions at two different levels. Details of both “placebo” samples are described in G ( a ). Spike recovery experiment was performed by spiking the nonvolatile ginger constituent reference material solution (known concentration) immediately after weighing the samples. Three separate sample preparations were conducted ( n = 3). The diluent was added afterwards to make the total extraction solution volume 10 mL. ( f ) Precision.— Eight dietary ingredients and supplements in different matrices were run to demonstrate repeatability and reproducibility of the method. Two NIST SRM samples were tested to further evaluate accuracy and repeatability of the method. All of the 10 dietary ingredients and supplements examined for repeatability were tested in quadruplicate ( n = 4) in day 1 by analyst 1 on instrument 1. The within-day results, repeatability (RSD r ), and HorRat r values for each nonvolatile ginger constituent were then calculated for all materials investigated. For evaluating method intermediate precision, eight dietary ingredients [ginger rhizome, dry extract, oleoresin (super critical fluid CO 2 soft extract)] and dietary supplements (tablets, capsule, liquid softgel capsule) were screened as target matrices. Three runs were conducted. Two analysts prepared four replicates of each sample, on 3 separate days, on three different instruments (run 1: day 1, analyst 1, instrument 1; run 2: day 2, analyst 2, instrument 2; run 3: day 3, analyst 2, instrument 3). A total of 12 replicate

preparations ( n = 12) were determined for each type of sample for precision determination. Between-day results, reproducibility (RSD R ), and HorRat R values were documented. H. Data Analysis Agilent ChemStation was used to automatically determine individual nonvolatile ginger constituents as follows: Analyte in sample, % = [area (sample) – calibration equation intercept × 100%]/ [calibration equation slope × sample (mg/mL)] Results were analyzed by using one-way analysis of variance (ANOVA) followed by independent t -tests with Tukey’s adjustment when there were significant differences among groups. All data were analyzed using Statistix software (version 10.0; Analytical Software, Tallahassee, FL, USA). References: (1) Manasa, D., Srinivas, P., & Sowbhagya, H. (2013) Food Chem. 139 , 509–514

(2) Ruggedness Test for Procedures (1975) W.J. Youden & E. Steiner (Eds.), Statistical Manual of AOAC , pp 33–36 (3) A.H.P. Association, Zingiber officinale (rhizome) (2018) http://www.botanicalauthentication.org/index. php/Zingiber_officinale_(rhizome) (accessed August 19, 2018) AOAC SMPR 2017.012 (Ginger) J. AOAC Int. 100 , 1192(2017) DOI: 10.5740/jaoacint.2017.012 You, H., Ireland, B., Moeszinger, M., Zhang, H., Snow, L., Krepich, S., & Takagawa, V. (2019) Talanta 194 , 795–802 (Original publication) J. AOAC Int . (future issue) (First Action)

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