AOAC 133rd Annual Meeting - Final Program

Poster Abstracts | Tuesday

P-T-054 Violet Brunkhorst , Carrie Maune , Julie Brunkhorst , Trilogy Analytical Laboratory, Washington, MO, USA The Effect of Grind and Extraction Size on Zearalenone Result Variability In the 2018 corn crop, zearalenone was found in several areas of corn growing regions in the United States. In many years, zearalenone is detected at low levels in areas of the U.S., however, in 2018, the contamination levels were found to be higher than in typical years. These types of crop years highlight the importance of proper sample preparation for zearale- none in corn. Sample preparation of products being tested for zearalenone is a critical part of the total analytical process. The difference in sample grind size, as well as the amount of sample extracted can also contribute to the overall result variability. An evaluation was conducted to compare the extraction of corn naturally contaminated with zearalenone utilizing differ- ent sample grind and different sample extraction weights. The naturally contaminated corn was ground to various mesh sizes, homogenized and various sample sizes where extracted. The extractions were performed using acetonitrile/water (84/16) with a 1 hour on Eberbach shaker. The extracts were then analyzed by LC-MS/MS. Data presented shows the effect grind size and sample extraction size has on zearalenone result variability. Presenter: Julie Brunkhorst, Trilogy Analytical Laboratory, Washington, MO, USA, Email: julie@trilogylab.com P-T-055 Julie Brunkhorst , Violet Brunkhorst , Carrie Maune , Trilogy Analytical Laboratory, Washington, MO, USA The Effect of Grind and Extraction Size on Deoxynivalenol Result Variability Deoxynivalenol (DON) is a common problem in areas grow- ing barley in North America. Each year levels fluctuate from low to high. One thing remains constant however, sample preparation for this commodity is critical for obtaining accurate DON results. This study evaluates sample preparation of barley containing DON. Sample preparation is a critical part of the total analytical process. The difference in sample grind size, as well as the amount of sample extracted contributes to the overall result variability. An evaluation was conducted to compare the extraction of barley naturally contaminated with DON utilizing different sample grind and different sample extraction weights. The naturally contaminated barley was ground to various mesh sizes, homogenized and various sample sizes where extracted. The extractions were performed using acetonitrile/ water (84/16) with a 1 hour on Eberbach shaker. The extracts were then analyzed by LC-MS/MS. Data presented shows the effect grind size and sample extraction size has on DON results variability. Presenter: Julie Brunkhorst, Trilogy Analytical Laboratory, Washington, MO, USA, Email: julie@trilogylab.com

P-T-056 Hui Li , Cristina Nochetto , U.S. Food and Drug Administration, Laurel, MD, USA A Dilute-and-Shoot UPLC/MS/MS Method for Simultaneous Determination and Confirmation of Eleven Mycotoxins in Distiller’s Dried Grains with Solubles Distillers grains (DGs) are the primary by-product in the indus- trial production of ethanol. They have high nutrient value and are used in animal feed. To ensure the safety of DGs for use as animal feed, an effective multi-residue regulatory method is needed. Our laboratory has developed and validated an LC-MS/MS method that quantifies and confirms eleven myco- toxins in DDGS at levels of interest to FDA/CVM. Samples are extracted with acetonitrile/water and acetonitrile/water/formic acid sequentially; the combined crude extract are then divided into two groups before analyzed by UPLC/MS/MS: diluted 400-fold (deoxynivalenol; fumonisins B1 and B2); neutralized to pH to 7.5 with phosphate buffer then diluted 16-fold (4 aflatox- ins; ochratoxin A; zearalenone; T-2 and HT-2). The mycotoxins are quantified using internal standard calibration with isotope labeled compounds. This method has been subject to robustness testing, and its performance meets pertinent FDA guidelines for regulatory quantitative method validation. Presenter: Cristina Nochetto, U.S. Food and Drug Administration, Laurel, MD, USA, Email: cristina.nochetto@fda.hhs.gov P-T-057 Hard Mo , Yolanda Xiong , Leo Li , Herbalife NatSource (Hunan) Natural Products Co., Ltd, Changsha, China; Congmei Cao , Peter Chang , Gary Swanson , Herbalife Nutrition, Torrance, CA, USA A Single Laboratory Validation of a Test Method for the Quantitation of Ochratoxin A (OTA) in Raw Material and Finish Product by Enzyme-Linked Immunosorbent Assay (ELISA) Using DS2 Ochratoxin is a mycotoxin produced by Aspergillus and Penicillium species. It is a widespread contaminant for multi- ple food matrixes, such as grain, pork products, coffee, wine grapes, and resins. Ochratoxin A (OTA) is carcinogenic and is associated with human kidney diseases. At present, official OTA determinations are based on liquid chromatography with fluorescence detection (HPLC-FID) or HPLC with mass spectrom- etry detection (HPLC-MS), which need take 1-2 days. A quick and direct enzyme-linked immunosorbent assay (ELISA) with monoclonal antibody was developed for quantitation of OTA in both raw material and finished products, which will shorten turnaround time from 1-2 days to 2 hours. The samples were extracted with 70/30 methanol/water, the extraction and enzyme-conjugated OTA were mixed and added to the anti- body-coated microwell. After interaction, sample was measured by ELISA. The precision, accuracy, linearity, specificity and ruggedness were validated following AOAC Guidance for Single Laboratory Validation Procedure. The linearity/range of OTA was determined as 2-40 ppb. The recoveries of OTA from protein drink and Guarana extract powder were within

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