Date palm and saw palmetto seeds functional properties: antioxidant, anti-inflammatory and antimicrobial activities

Abstract

The agricultural by-products are a significant source of health benefiting bioactive compounds. In this trend, the phenolic and flavonoid contents and functional properties of date palm seeds (DPS) and saw palmetto seeds (SPS) extracts were evaluated in this study. Considerable phenolic and flavonoid contents of 11.8, 7.75 mg GAE/g seed and 3.13, 1.1 mg CE/g seed were detected in DPS ethanol and SPS acetone extracts, respectively. The protocatechuic acid was the major compound in SPS and DPS extracts and represented 1.41 and 1.1 mg/g seed, respectively as well as similar phenolic compounds were detected using HPLC analysis. The DPS and SPS phenolic compounds possessed a strong antioxidant activity with IC50 values of 10.0, 2.2 and 2.0, 0.6 µg GAE/mL, using the DPPH and ABTS assays, respectively. The phenolic compounds of DPS and SPS extracts showed a potent and broad anti-bacterial activity against clinical multiple drug resistance bacterial strains with lower MIC values besides an effective anti-fungal activity against a number of human pathogenic fungal strains. Interestingly, in a model of LPS-induced inflammation in RAW 264.7 cells, DPS and SPS showed efficient anti-inflammatory effects to inhibit the iNOS protein expression and activity (NO release).