Abstract:
Green spinach (Amaranthus hybridus) has a secondary metabolite like phenolic, flavonoid, and vitamin C that has antioxidant capability. This research was conducted with aim to determine total phenolic content, total flavonoid, vitamin C, and antioxidant activity in organically and conventionally grown green spinach. The antioxidant activity was analyzed using Ferric Thiocyanate (FTC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and NO radical
scavenging activity method. The organic green spinach was grown with five treatments and control (just water) as biocontrol. The treatments are EM5, mixture EM5 and garlic, and fermented plant extract (FPE) from rumput paitan (Paspalum Conjugatum Berg.),
babadotan (Ageratum mconyzoides L.), and spices. The highest total phenolic (0,940 mg
GAE/g) and total flavonoid content (0,773 mg QE/g) were found in green spinach that
treated with rumput paitan FPE and had significant difference (P<0,05) with other
treatment. Similar result was showed in antioxidant activity (76,319%) with FTC method. Vitamin C content of green spinach with rumput paitan FPE treatment is higher than other treatment but no significant difference with EM5 and garlic mixture (65,556 mg AAE/g) and babadotan FPE treatment (63,333 mg AAE/g). The best IC50 by DPPH method is showed in rumput paitan treated green spinach (11,063 mg/mL) but no significant difference with babadotan FPE (13,183 mg/mL). Green spinach with rumput paitan treatment also has the best IC50 (28,196 mg/mL) in NO radical scavenging activity method but no significant difference with spices FPE (31,871 mg/mL). In conclusion, green spinach with rumput paitan FPE gives the best value of total phenolic, total flavonoid, vitamin C,
and antioxidant activity
