Temulawak (Curcuma xanthorrhiza) merupakan salah satu rempah-rempah sumber antioksidan alami, digunakan untuk pengobatan tradisional dan bahan pembuatan minuman. Penelitian ini bertujuan untuk mengetahui aktivitas antioksidan bubuk simplisia temulawak dan bubuk sari temulawak serta kandungan kurkuminoidnya, pengaruh konsentrasi ethanol dan penutupan kain hitam pada saat pengeringan terhadap rendemen, kandungan kurkuminoid dan aktivitas antioksidan ekstrak bubuk simplisia temulawak, pengaruh rasio bahan : air terhadap rendemen, kandungan kurkuminoid dan aktivitas antioksidan ekstrak bubuk sari temulawak serta aktivitas antioksidan ekstrak bubuk simplisia temulawak dan sari temulawak dibandingkan dengan asam sitrat pada sistem yang mengandung inisiator Fe. Penelitian ini diawali dengan pembuatan simplisia temulawak dan sari temulawak. Simplisia temulawak dibuat dengan 2 perlakuan pengeringan yaitu dengan penutupan kain hitam dan tanpa penutupan kain hitam. Sari temulawak dibuat dengan 3 macam rasio bahan : air yaitu 1 : 1, 1 : 2 dan 1 : 3. Bubuk simplisia temulawak diperoleh dengan menghancurkan simplisia temulawak sedangkan bubuk sari temulawak diperoleh dengan perlakuan pengendapan dan tanpa pengendapan pada sari temulawak kemudian diuapkan airnya menggunakan vacuum rotary evaporator. Bubuk simplisia temulawak diekstrak menggunakan ethanol dengan konsentrasi 0%, 50% dan 95%. Bubuk sari temulawak diekstrak menggunakan ethanol 95%. Ekstrak bubuk simplisia temulawak dan sari temulawak kemudian diukur rendemen, kandungan kurkuminoid menggunakan HPLC dan diuji aktivitas antioksidannya menggunakan metoda ferri thiosianat dan asam thiobarbiturat. Pengujian aktivitas antioksidan dengan 2 perlakuan yaitu tanpa inisiator dan dengan inisiator Fe serta sebagai pembanding digunakan asam sitrat Hasil penelitian menunjukkan bahwa ekstrak bubuk simplisia temulawak dan sari temulawak mengandung senyawa kurkuminoid dengan jumlah yang berbeda tetapi aktivitas antioksidannya tidak berbeda. Semakin tinggi konsentrasi ethanol (sampai dengan konsentrasi 95%) menyebabkan rendemen ekstrak bubuk simplisia temulawak semakin rendah tetapi kandungan kurkuminoid dan aktivitas antioksidannya semakin tinggi. Penutupan dengan kain hitam pada waktu pengeringan dapat meningkatkan rendemen, kandungan kurkuminoid dan aktivitas antioksidan ekstrak bubuk simplisia temulawak. Bubuk sari temulawak yang diperoleh dengan ekstraksi menggunakan air dengan rasio bahan : air = 1 : 2 tanpa perlakuan pengendapan mempunyai kandungan kurkuminoid dan aktivitas antioksidan tertinggi. Ekstrak bubuk simplisia temulawak dan sari temulawak mempunyai aktivitas antioksidan yang lebih tinggi daripada asam sitrat dan penambahan inisiator Fe serta asam sitrat tidak berpengaruh terhadap aktivitas antioksidannya.

Temoelawak (Curcuma xanthorrhiza) is one of spices to be natural antioxidant sources, used for traditional medication and materials for making beverage. This research was aimed to find out antioxidant activity and curcuminoid content of temoelawak chip powder and concentrate, effect of ethanol concentration and covering black cloth during drying to the yield, curcuminoid content and antioxidant activity of temoelawak chip powder extract, effect of ratio between material : water to the yield, curcuminoid content and antioxidant activity of temoelawak concentrate powder extract, antioxidant activity of temoelawak chip powder extract and temoelawak concentrate powder extract compared with citric acid in the system containing initiator Fe. This research was started with preparation temoelawak chip and temoelawak concentrate. The temoelawak chip was made from 2 treatments of drying those were covering black cloth and without covering black cloth. The temoelawak concentrate was made by ratio between material : water e.i. 1 : 1, 1 : 2 and 1 : 3, respectively. The temoelawak chip powder was obtained by crushing temoelawak chip while the temoelawak concentrate powder was acquired through sedimentation treatment and without sedimentation to the temoelawak concentrate then evaporated its water using vacuum rotary evaporator. The temoelawak chip powder was extracted using ethanol with concentration 0%, 50% and 95%. The temoelawak concentrate powder was extracted using ethanol 95%. The temoelawak chip powder extract and temoelawak concentrate powder extract than were measured its yield, curcuminoid content by using HPLC and evaluated its antioxidant activity using ferri thiocyanat and thiobarbituric acid methode. The evaluation of antioxidant activity with 2 treatments that was with initiator and without initiator Fe and as comparison used citric acid. The result indicated that the temoelawak chip powder extract and temoelawak concentrate powder extract its curcuminoid were differ, but its antioxidant activity were not differ. The higher ethanol concentration (up to the concentration 95%) decreased the yield of temoelawak chip powder extract, but its curcuminoid content and antioxidant activity increased. Drying with covering black cloth increased the yield, curcuminoid content and antioxidant activity of temoelawak chip powder extract. The temoelawak concentrate powder that were obtained with extraction with ratio between material : water = 1: 2 without sedimentation had the highest curcuminoid content and antioxidant activity. The temoelawak chip powder extract and temoelawak concentrate powder extract had higher antioxidant activity than citric acid and the existence of initiator Fe and citric acid were not affected to the antioxidant activity of temoelawak chip powder extract and temoelawak concentrate powder extract.

Kata Kunci : Temu Lawak,Antioksidan,Kurkuminoid, Temoelawak (Curcuma xanthorrhiza), antioxidant, curcuminoid