Kadar Total Fenolik dan Aktivitas Antioksidan Ekstrak Metanol Gandarusa yang Dibudidaya dengan Kombinasi Pupuk Kandang dan NPK

Abstract

Pengaplikasian pupuk organik dan anorganik akan memengaruhi kadar senyawa fenolik tanaman gandarusa. Penelitian ini bertujuan menentukan metode budidaya terbaik melalui aplikasi pupuk kandang, NPK, atau kombinasi keduanya terhadap kadar total fenolik dan aktivitas antioksidan ekstrak metanol daun dan batang gandarusa. Tanaman gandarusa dibudidaya dengan enam perlakuan, yakni kontrol (T1), pupuk kandang (T2), NPK (T3), 50% pupuk kandang + 50% NPK (T4), 50% pupuk kandang + 10% NPK (T5), dan 10% pupuk kandang + 50 % NPK (T6). Total fenolik diukur dengan metode Folin Ciocalteu. Aktivitas antioksidan diukur dengan metode Ferric Reducing Antioxidant Power (FRAP) dan 2,2’-difenil-1-pikrilhidrazil (DPPH). Kadar total fenolik tertinggi diperoleh pada perlakuan T3 daun dan T6 batang (4,28 dan 2,54 mg GAE/g bobot kering). Aktivitas antioksidan FRAP tertinggi diperoleh pada perlakuan T3 daun dan batang, sedangkan pada metode DPPH perlakuan T1 daun dan T6 batang menunjukkan aktivitas tertinggi (11,54; 5,31; 0,64; 0,19 µmol TE/g bobot kering). Kadar total fenolik hanya menunjukkan korelasi yang positif dan signifikan terhadap aktivitas antioksidan sampel daun metode FRAP.

The application of organic and inorganic fertilizers affects to the levels of gendarussa plant’s phenolic compounds. This research aims to determine the best cultivation method using manure, NPK, or the combination to achieve the highest phenolic content and antioxidant activity in methanol extract of gendarussa. Gendarussa plants are cultivated with six treatments, control (T1), manure (T2), NPK (T3), 50% manure + 50% NPK (T4), 50% manure + 10% NPK (T5), and 10% manure + 50% NPK (T6). Total phenolic was measured by Folin Ciocalteu method. Antioxidant activity was determined by FRAP and DPPH assay. The highest phenolic content was obtained from sample T3 (leaf) and T6 (stem) (4,28 and 2,54 mg GAE/g dry weight). The highest FRAP antioxidant activity was obtained from sample T3 of both leaf and stem, while the highest DPPH antioxidant acitivity was obatained from sample T1 (leaf) and T6 (stem) (11,54; 5,31; 0,64; 0,19 µmol TE/g dry weight). Total phenolic content only shows a positive and significant correlation to the antioxidant activity of leaf samples using FRAP assay.