A Comparison of Nutritional Values, Bioactive Compounds, Amino Acids, and Antioxidant Activities of Alfalfa (Medicago sativa) Plant and Pellet for Use as Beneficial Material Ruminant Feed

Abstract

Aqueous extracts of whole alfalfa plants (AP) and alfalfa pellets (APe) were examined for nutritional values, bioactive compounds (total phenolic content (TPC), phenolic compounds (PC), total flavonoids content (TFC), flavonoids compounds (FC), isoflavones), amino acids (AA) and antioxidant activity of AP and APe assessed via a DHHP radical scavenging assay and ferric reducing antioxidant power (FRAP) assay. The potential ingredients in the form of AP and APe were used to evaluate the nutritional values measured by chemical composition, and to investigate bioactive compounds, AA and antioxidant activity to further contribute to use as a feed ingredient or application as a high-value alternative feed supplement in the ruminant diet. Crude protein and tannins were higher in the APe (18.17 and 3.08 %) than the AP (16.21 and 1.80 %). Higher content of organic matter, crude fiber, neutral-detergent fiber, acid-detergent fiber, acid-detergent lignin was observed for AP than APe. The TPC and TFC were more abundant in AP than in APe and AP also showed stronger antioxidant activity via DPPH than APe, with positive correlations of TPC, TFC and DPPH. The highest values of gallic acid in terms of PC and apigenin in terms of FC of APe were 215.30 and 2278.27 µg/g dry weight (DW), respectively, while the highest levels of genistein and daidzein occurred in AP at 104.37 and 130.91 µg/g DW, respectively. The total of essential AA was found to be in vary the range of 9.33 to 16689.47 µg/g DW in different forms of samples, with valine as the highest (5451 µg/g DW) in APe, followed by phenylalanine (4.30 µg/g DW) in AP.