Abstract
Quinoa (Chenopodium quinoa) is classified as one of the pseudo-cereal grains rich in both macronutrients and micronutrients. This study tracks changes in the polyphenol composition of red quinoa (RQ) and yellow quinoa (YQ) seeds during germination. The antioxidant bioactivity of raw and germinated seed was also determined in vitro. Phenolic acids and their derivatives and flavonoids were identified by using HPLC-DAD and quantified after 0, 3, and 6 days of germination. Subsequently, the extracts of 6-day-old quinoa sprouts were prepared to biologically evaluate their functional properties against CCl4-induced oxidative stress in rats. The results indicated that antioxidant activity (AOA) of total phenolic compounds (TPC), and flavonoids significantly increased in RQ and YQ sprouts during germination up to 9 days. RQ sprouts exhibited stronger bioactive compound diversity than YQ sprouts as observed in HPLC analysis. Among the 11 and 8 quantified polyphenols, ferulic acid and quercetin were predominant phenolic acid and flavonoid in RQ and YQ sprouts, respectively. After 6 days of germination, 16 and 8 polyphenols were detected and quantified in RQ and YQ sprouts, respectively. Interestingly, the treatment of rats at a dose of 30 mg of Gallic acid Equivalent (GAE) kg(-1) significantly reduced fasting blood glucose (FBG), alanine aminotransferase (ALT), aspartate aminotransferase AST, and total bilirubin (TIBIL) and improved liver inflammation. Furthermore, RQ and YQ sprouts improved the blood profile by significantly decreasing low-density lipoproteins (LDL) and very low-density lipoproteins (VLDL) and increasing high-density lipoproteins (HDL). Moreover, RQ and YQ sprout extracts significantly reduced malonaldehyde (MDA) and efficiently enhanced the reduced glutathione (GSH) and superoxide dismutase (SOD) activities in oxidative stress-induced rats as compared to CCl4-rats. In conclusion, red quinoa sprouts (RQS) and yellow quinoa sprouts (YQS) provide naturally synthesized polyphenols, possessing superior antioxidant activity, and their ethanolic extracts have promising effects and potential health benefits to counter induced oxidative stress. Incorporating quinoa sprouts as functional food ingredients should be considered and scaling-up its production is beneficial.