Karakterisasi senyawa bioaktif isoflavon dan uji aktivitas antioksidan dari ekstrak tempe berbahan baku buncis (Phaseolus vulgaris) dan kecipir (Psophocarpus tetragonolobus)

Oleh :
Sri Wahyuni - S900208023 - Sekolah Pascasarjana

ABSTRAK Biji buncis dan kecipir yang tergolong leguminoceae berpotensi sebagai sumber antioksidan alami. Penelitian ini bertujuan mengetahui kandungan isoflavon aglikon dan membandingkan aktivitas antioksidan pada buncis, kecipir, kedelai kuning dengan antioksidan alami maupun antioksidan BHT (Butyl Hidroksi Toluena). Metode untuk ekstraksi isoflavon dengan maserasi, identifikasi isoflavon dengan HPLC, uji aktivitas antioksidan dengan DPPH. Untuk mengetahui perbedaan antar perlakuan fermentasi dan penghitungan aktivitas antioksidan dianalisis dengan General Linear model-Univariete, untuk membandingkan tingkat aktivitas antioksidannya dianalisis dengan Compare Means-One Way Annova, menggunakan program SPSS version 15. Hasil penelitian menunjukkan bahwa biji kedelai kuning, buncis dan kecipir mentah memiliki total isoflavon masing-masing sebanyak (0,18%), (0,15%), dan (0,21%). Pada kedelai kuning mentah tidak ditemukan isoflavon factor-2, tetapi buncis dan kecipir mentah ditemukan sebanyak (0,006%) dan (0,001%). Pada hasil fermentasi buncis, kecipir, kedelai kuning ditemukan jenis isoflavon factor-2, daidzein, glisitein, genistein. Hasil uji aktivitas antioksidan, berurutan dari tinggi ke rendah adalah tempe kecipir 0-hr (85,19%), tempe kedelai 3-hr (81,43%), BHT (81,15%), α-tokoferol (76,41%), vitamin C (75,62%), tempe buncis 0-hr (52,95%) dan β-karoten (43,25%). Aktivitas antioksidan pada tempe kecipir 0-hr signifikan lebih besar dari kedelai kuning fermentasi 3-hr maupun BHT, berarti kecipir berpotensi sebagai sumber antioksidan yang prospektif untuk digunakan sebagai pengganti kedelai kuning dan BHT. Aktifitas antioksidan pada buncis signifikan lebih rendah dari antioksidan BHT, α-tokoferol, vitamin C tetapi masih lebih tinggi dari antioksidan β-karoten. Kata kunci : Buncis, Kecipir, Fermentasi, Isoflavon, Aktivitas antioksidan ABSTRACT Pole bean and Winged bean belong to leguminoceae which have a potential as natural antioksidan resource. The aims of the research at finding out the content of the isoflavone aglikon compounds and comparing the antioxidant activity of the pole bean, winged bean, and yellow soybean with both the natural antioxidant and BHT antioxidant. The methods used to extract the isoflavone compounds were maceration, identification of isoflavone by using HPLC, and test of antioxidant activity was done with DPPH. To know the difference between fermentation treatment and the measurement of antioksidan activity which was analized by General Linear Model-Univariete, to compare the level of antioxidant activity which was analized by Compare Means-One Way Annova using the program of SPSS version 15. The results of the research show that the whole soybean, pole bean, and winged bean seed had the total contents of the isoflavone compounds of 0.18%, 0.15%, and 0.21% respectively. The isoflavone of factor-2 was not found in the yellow soybean, but it was found in the pole bean (0.006%) and in the winged bean (0.001%). In the fermentation result of pole bean, winged bean and yellow soybean was I found kind of the isoflavone compounds of factor-2, daidzein, glisitein and genistein. The results of the antioxidant activity test show that the antioxidant activity from the highest to the lowest was owned by winged bean tempeh in the 0-day fermentation (85.19%), soybean tempeh in the 3-day fermentation (81.43%), BHT (81.15%), α-tocoferol (76.41%), vitamin C (75.62%), pole bean tempeh in the 0-day fermentation (52.95%), and ß-carotene (43.25%). Antioxidant activity in the winged bean tempeh in the 0-day fermentation was higher than and really different from the yellow soybean in the 3-day fermentation and BHT, meaning that the winged bean had the potential to be the antioxidant resource which was prospective to be used as a substitute for the soybean and BHT. The antioxidant activity of the pole bean was lower than that of BHT, α-tocoferol, and vitamin C, but was higher than that of ß-carotene. Keywords: Pole bean, winged bean, fermentation, isoflavone, antioxidant activity