Oat Avenanthramides (Ava) Are Bioavailable In Humans After Acute Consumption Of Oat Cookies

Objectives Avenanthramides (AVA) are a group of diphenolic acids that are found only in oats and have anti‐inflammatory and antioxidant effects. Although previous publications have reported AVA are bioavailable in humans, our study is the first to examine whether AVA are bioavailable in humans after acute consumption of oat cookies made with natural and non‐treated oat flour. We examined the metabolic fate of orally ingested oat AVA by measuring plasma AVA concentrations and their pharmacological characteristics. Methods Sixteen male and female non‐obese subjects were enrolled in a randomized, crossover trial. Subjects received three cookies made with oat flour containing high (229.6 mg/kg, H‐AVA) or low (32.7 mg/kg, L‐AVA) AVA on separate occasions. The H‐AVA cookie (7.2 mg/cookie; 21.6 mg total) contained 5.09 mg AVA‐A, 8.67 mg AVA‐B and 7.85 mg AVA‐C, whereas the L‐AVA (1.03 mg/cookie; 3.09 mg total) contained 0.57 mg AVA‐A, 0.95 mg AVA‐B and 1.55 mg AVA‐C. Subjects consumed the cookies in the morning after 10 h fast and blood samples were collected at 0 (baseline), 0.5, 1, 2, 3, 5 and 10h. Plasma total (conjugated and free) AVA were quantified with Ultra Performance Liquid Chromatography Quadrupole Time‐of‐Flight Mass Spectrometer (UPLC Q‐TOF‐MS), and pharmacokinetic (PK) parameters were calculated and presented as mean±SD. Half life time (T 1/2 ) was calculated through logarithmic transformation and elimination constant (K el ) was calculated using equation K el =0.693/T 1/2 . At least three time points in elimination phase were required to calculate T 1/2 . All plasma concentrations used for estimation of PK parameters were above assay limit of quantitation. Results AVA‐A, ‐B and ‐C were present at the peak concentration (T max ) in plasma at 2.50±1.2 h, 2.04±0.9 h and 2.29±1.0 h in H‐AVA and at 1.80±1.3 h, 1.50±1.5 h and 1.32±1.0 h in L‐AVA, respectively. Maximal plasma concentrations (C max ) for AVA‐A, ‐B and ‐C were 8.39±4.2 ng/ml, 8.44±2.3 ng/ml and 4.26±2.0 ng/ml in H‐AVA, and 1.98±1.3 ng/ml, 2.43±1.1 ng/ml and 1.33±0.7 ng/ml in L‐AVA, respectively ( P <0.001). H‐AVA cookies led to significantly higher AVA‐A and ‐B than ‐C concentrations ( P <0.05). Half‐life (T 1/2 ), the time taken to fall to half initial value was 2.16±0.6 h, 4.23±0.8 h and 2.71±1.2 h in H‐AVA, and 2.44±0.8 h, 4.60±2.7 h and 2.87±1.4 h in L‐AVA, respectively ( P <0.05, AVA‐B vs. AVA‐A or AVA‐C in H‐AVA). Conclusions AVA found naturally in oats are bioavailable in humans. AVA‐B has the slowest elimination rate and highest half‐life compared to AVA‐A and AVA‐C, while AVA‐C has the lowest absorption rate. Support or Funding Information This study is sponsored by PepsiCo Nutrition.