The effects of drying temperature on the content of polyphenol compounds, carotenoids, chlorophyll pigmented and antioxidant activity of the “rau cang cua” (Peperomia pellucida L.) collected in Tien Giang province

The objective of this study is to determine the effect of the drying temperature on the content of the bio-compounds in “rau cang cua” (Peperomia pellucida L.) and antoxidant of these extract. They were dried to the moisture content of ≤ 10% at the temperatures of 50, 60, 70, and 80oC, and then they were finely ground to powder. “Rau cang cua” powder was extracted with ethanol 70%, received extracts and analyzed the total polyphenol (TPP), carotenoids, chlorophyll pigmented and the percentage of scavenging free radical DPPH. When “rau cang cua” were dried at the temperature of 50 - 80oC, TPP content ranged 6.65 - 12.88 (mgGAE/g DM), carotenoids ranged 96.88 - 132.78 (µg/g DM), chlorophyll a and b ranged 800.59 - 1,205.60 and 560.94 - 665.40 (µg/g DM) respectively and the percentage of scavenging free radical DPPH ranged 53.73 - 69.54%. The “rau cang cua” samples were dried at the temperature of 70℃ had TPP content, antioxidant higher and it also retain the color pretty good compared with 3 remain samples