<![CDATA[ABSTRAKBeras ketan (Oryza sativa var. glutinosa) yang umum dikenal dan dimanfaatkan masyarakat saat ini adalah beras ketan putih dan beras ketan hitam, sedangkan beras ketan merah sangat jarang diketahui oleh sebagian besar masyarakat. Masyarakat di daerah tertentu seperti di Pakis, kabupaten Pacitan telah lama mengenal, menanam, dan mengolah beras ketan merah menjadi snack seperti tape ketan merah, rengginang ketan merah, dan lain sebagainya. Diduga ketan merah sama seperti beras berpigmen lainnya mengandung asam fenolat dan senyawa bioaktif lainnya serta memiliki aktivitas antioksidan. Penelitian ini bertujuan untuk identifikasi kandungan asam fenolatat pada ketan pecah kulit, ketan sosoh dan bekatulnya. Setiap sampel diekstrak kandungan fenolat bebas, fenolat terikat dan fenolat terkonjugasi kemudian hasil ekstraksi dianalisis total fenolat metode folin-ciocalteau serta aktivitas antioksidan metode DPPH. Penelitian ini bersifat deskriptif kuantitatif, dengan tiga kali ulangan. Pada semua sampel, baik pada ketan pecah kulit, ketan sosoh (bagian endosperm) maupun bekatul (bran) mengandung lebih banyak total fenolat terikat dan terkonjugasi (bebas-terikat) daripada fenolat bebas. Aktivitas antioksidan ekstrak senyawa fenolat tertinggi terdapat pada ketan merah pecah kulit meliputi semua jenis fenolat yaitu ekstrak fenolat bebas IC50 4.52 mg/ml, fenolat terkonjugasi 3 IC50 9.92 mg/ml dan fenolat terikat IC50 30.65 mg/ml ABSTRACTThe most common Glutinous rice (Oryza sativa var. glutinosa) is white glutinous rice and black glutinous rice, but red glutinous rice rather infrequently. However, only few people have known about red glutinous rice, local glutinous cultivars in Pakis, Pacitan, East Java. People in there are used to cultivating red glutinous rice for long time ago and processing into various kinds of snack, such as tape, rengginang. Like the other pigmented rice, red glutinous rice contained phenolic and other bioactive compounds which contained antioxidant activity. This study investigated the phenolic compounds of unpolished red glutinous rice, polished red glutinous rice and bran red glutinous rice. Free phenolic compounds was extracted from each samples, as well as the bound-free phenolic and bound phenolic, then analyzed total phenolic and antioxidant activity by using DPPH method. This research was quantitative descriptive with triplicate measurements. The total phenolic content (TPC) of both bound phenolic acids extract and free/ conjugated phenolic acids extract were higher than free phenolic acids extract in all samples, including unpolished red glutinous rice, polished red glutinous rice and bran red glutinous rice. Antioxidant capacity of all kinds of phenolic acids extract was highest in unpolished red glutinous rice, that is free phenolic acids extract IC50 4.52 mg/ml, free/conjugated phenolic acids extract 3 IC50 9.92 mg/ml and bound phenolic acids extract IC50 30.65 mg/ml]]>
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