Phenolics, Flavonoids and Antioxidant Activity of Vegetables as Thai Side Dish

The total phenolics, flavonoids and antioxidant activity of 21 selected kinds of Thai side dish vegetables were determined. The result showed that all kinds of Thai side dish vegetables contained phenolic and flavonoid compounds. The Thai side dish vegetables that contained the highest phenolic compound was Pak bung tai muang, 1.66±0.006 mgGAE/g. As Ma khua puang and Kra jeab kheaw contained the highest flavonoid compound (0.14±0.001 mgRE/g). In the part of antioxidant activity, Kha-on displayed the highest antioxidant activity with 91.99±1.36%inhibit by DPPH assay and 1.65±0.03 mM FeSO4 by FRAP assay method. Although this result revealed that Thai side dish vegetables may not high source of phenoloic and flavonoid compounds, they showed high efficiency of antioxidation power. It was suggested that Thai side dish vegetables would become new good source and natural of phenolic and flavonoid compounds because Thai people generally ate most of all vegetables as side dish in fresh cut and scald so phenolics and flavonoids were not destroyed from cooking process. In addition, they usually consumed Thai side dish fresh cut vegetables at least 100 gram/time/person which were benefit for the human health.