Table 5. ABTS radical scavenging ability of 70% ethanol extracts of grape fruit stem with different drying methods
| Samples1) | Concentration (μg/mL) | Positive control2) (50 μg/mL) |
| 50 | 100 | 500 | AA | BHA | BHT |
| GFSF | 44.95±1.093)a4) | 83.84±2.46a | 93.67±0.19a | 98.61±0.13A | 97.96±0.16B | 90.96±0.61C |
| GFSI | 42.41±2.63ab | 82.02±0.95ab | 93.20±0.12a |
| GFSH | 40.86±2.06b | 80.07±2.12b | 91.60±0.81b |
| GFSS | 29.68±1.04c | 56.11±1.53c | 91.49±0.69b |
1)Abbreviations: GFSF, ethanol extract of grape fruit stem with freeze drying; GFSI, ethanol extract of grape fruit stem with infrared drying; GFSH, ethanol extract of grape fruit stem with heat air drying; GFSS, ethanol extract of grape fruit stem with sun drying.
2)AA, L-ascorbic acid; BHA, butylated hydroxyanisole; BHT, butylated hydroxytolune.
3)Values are means±SD of triplicate determinations.
4)Different superscripts within a column (a-c) and row (A-C) indicate significant differences (p<0.05).