Analisis kandungan total Fenolik, Flavanoid dan kapasitas Antioksidan biji Kedelai (Glycine max (L.) Merill) yang terinfeksi Jamur Phakopsora pachyrhizi Syd.

ABSTRAK

Tanaman kedelai sangat rentan terhadap penyakit. Penyakit yang umum diderita tanaman kedelai adalah penyakit karat yang disebabkan oleh jamur P. pachyrhizi. Setiap tanaman mempunyai respon terhadap serangan patogen, adanya infeksi jamur P. pachyrhizi, tanaman akan merespon serangan dengan mekanisme pertahanan membentuk senyawa antifungal. Penelitian ini bertujuan untuk mengetahui perbandingan kandungan metabolit sekunder antara biji kedelai inokulasi P.pachyrhizi dan non inokulasi.

Jamur P. pachyrhizi pada penelitian ini diinokulasikan pada 15 galur tanaman kedelai melalui teknik preharvest (sebelum panen). Biji kedelai hasil panen (inokulasi dan non inokulasi) diekstrak menggunakan metode maserasi menggunakan pelarut 80% metanol. Pengujian total fenolik menggunakan metode Folin Ciocalteau, total kandungan flavonoid menggunakan reagen alumunium klorida, dan kapasitas antioksidan menggunakan metode DPPH 0,1 mM.

Hasil penelitian menunjukkan bahwa infeksi jamur P.pachyrhizi pada tanaman kedelai menunjukkan adanya perubahan kandungan fenolik dan flavanoid dan kapasitas antioksidan pada 15 galur biji kedelai. Hasil pengujian total fenolik pada 15 galur biji kedelai inokulasi P. pachyrhizi mengalami penurunan. antara 2% hingga 61%. Kandungan flavonoid rata-rata mengalami penurunan sebesar 3% hingga 32%, kenaikan hanya terjadi pada galur 6 sebesar 5% dan galur 12 sebesar 2%. Sedangkan kapasitas antioksidan, rata-rata biji kedelai inokulasi P. pachyrhizi mengalami kenaikan sebesar 1,5% hingga 24%, penurunan hanya terjadi pada galur 7 (4%), galur 13 (13%) dan galur 14 (16%). Adanya infeksi jamur P. pachyrhizi pada tanaman kedelai tidak dapat menstimulasi peningkatan kandungan senyawa fenolik dan flavanoid, hanya meningkatkan kapasitas antioksidan pada biji kedelai.

ABSTRACT

Soybean plant is susceptible to disease. The common disease found in soybean plant is rust caused by P. pachyrhizi fungus. Every plant haves response toward pathogen attack, the existence of P. pachyrhizi fungus infection,the plant will response the attack by making fortress mechanism forms antifungal compound. This research was aimed to find out comparison of secondary metabolite content between inoculated and non-inoculated P. pachyrhizi soybean seed.

P. pachyrhizi. Fungus in this research was inoculated toward soybean plant by using pre-harvest technique. Soybean seeds harvested (inoculated or non-inoculated one) were extracted through maceration method by using 80% of methanol as the solvent. Further, to prove this hypothesis, a test by determining total phenolic was conducted by using Folin Ciocalteau 6,7 %, total content of flavonoid by using aluminum chloride calorimetric and capacity of antioxidant by using DPPH 0,1 mM.

This result shows that P. pachyrhizi fungus infected on Soybean seed shows there are content phenolic, flavonoid, and capacity of antioksidant change on 15 galur soybean seed. The test result of total phenolic in the inoculated soybean seed of P. pachyrhizi decreased between 2% up to 61%. The content of flavonoid averagely got decreased in amount of 3% up to 32%, the decrease merely occurred in channel 6 in amount of 5% and channel 12 in amount of 2%. While the average antioxidant capacity of inoculated P. pachyrhizi soybean seed decreased in amount of 1,5% up to 24%, the decrease merely occurred in channel 7 (4%), channel 13 (13%) and channel 14 (16%). The existence of P.pachyrhizi fungus infection on soybean plant can not stimulate the increase of comporasion of phenolic and flavanoid, it only increased capacity of antioxidant on soybean seed.