ABSTRAKBunga rosella mengandung senyawa bioaktif dengan kadar antosianin yang tinggi. Antosianin termasuk golongan senyawa flavonoid yang dapat berperan sebagai antioksidan alami, mampu menghambat radikal bebas serta dapat mencegah terjadinya degeneratif sel dan penyakit lain. Tujuan penelitian adalah mempelajari pengaruh jenis pelarut dan temperatur pada ekstraksi rosella terhadap aktivitas dan kadar antosianin. Manfaat penelitian ini adalah menerapkan hasil peneliti ekstraksi antioksidan pada rosella bagi dunia usaha. Metode penelitian terdiri dari persiapan bahan baku, ekstraksi antosianin dan analisis. Rosella yang telah dikeringkan diekstraksi masing-masing menggunakan campuran pelarut etanol:air dengan variasi 0:100, 50:50 dan 70:30 % v/v , ekstraksi dilakukan masing-masing pada temperatur 30 ˚C, 45 ˚C, dan 60 ˚C. Analisis kimia meliputi penentuan kadar antosianin dengan metode pH differensial, penentuan aktivitas antioksidan dilakukan dengan metode DPPH (1,1-difenil-2 pikrilhidrazil). Hasil penelitian pada kondisi optimum ekstraksi adalah menggunakan pelarut etanol:air (50:50 v/v) pada temperatur 45 ˚C, kadar antosianin dan rendemen tertinggi masing-masing adalah 88,9 mg/L dan 53,2 %. Aktivitas antioksidan tertinggi ditunjukan dengan nilai IC50 yaitu 67,3 ppm. Penentuan kestabilan antosianin dilakukan dengan memberi perlakuan termal pada temperatur 30 ˚C, 45 ˚C, dan 60 ˚C, dari persamaan Arhenius diperoleh nilai energi aktivasi 18,3 kJ/mol.Kata Kunci: Rosella, ekstraksi, pelarut, temperatur, analisis, antioksidanABSTRACTRoselle contains bioactive compounds and has high quantity of anthocyanin. Anthocyanins, including flavonoid compounds that can be used as natural antioxidants, that has the ability to inhibit free radical reaction, in human body can prevent degenerative cell and various diseases. The objective of this research is to study the effect of solvent and temperature in a batch extraction of roselle to the anthocyanin product. The benefit of this research is to give the transfer of extraction product for the benefit of industry. Method used in this research consisting of the preparation of size reduction of roselle into smallest size followed by drying process, and extraction of roselle. Extraction can be done by two variables, namely ratio ethanol and water of 0:100 ; 50:50 ; 70:30 v/v respectively and temperature of 30oC, 45oC and 60oC. Analysis anthocyanin content was evaluated by the pH differential method, and the activity of antioxidant using a method of DPPH (1,1-diphenyl-2-picrylhydrazil). The research results can be shown that the optimum condition of temperature 45oC and ethanol water ratio of 50:50 followed by total anthocyanin of 88.9 mg/L, and yield content of 53.2%. The highest antioxidant activity indicated by IC50 value of 67.3 mg/L. The effect of temperature in a batch extraction process followed Arrhenius equation with energy activation of 18.3 kJ/mol.Keywords: Roselle, extraction, solvent, temperature, analysis, antioxidant

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Zeolites are microporous crystalline aluminosilicates extensively used as adsorbents, catalysts, and ion exchange beds. The adsorption property of zeolite is expected to be applied as a decolorization agent for terpineol. Terpineol is an alcohol compound derived from turpentine oil and widely used as an active ingredient for disinfectants, cleansers, perfumes, and pharmaceutical purposes. Industrial-scale of terpineol production used two stages of reaction: the first stage is hydration of turpentine into terpin hydrate and the second stage is dehydration of terpin hydrate to terpineol. However, as terpin hydrate is easily oxidized, the product color will change from clear into dark solution and make the price of product cheaper. This study aims to increase terpineol selling price by removing unreacted terpin hydrate (decolorization) from crude terpineol. Zeolite is the main absorbent used in this study along with other similar materials i.e. activated carbon and silica gel. Performances of the adsorbent are indicated by its adsorption capacity and color clarity analysis. The results would be analyzed using GC-MS. Based on the experiment, it can be concluded that the best adsorbent is zeolite activated by acetic acid with 8-15 mg/g adsorption capacity and producing a terpineol purity of 83.5%. This activated zeolite was able to remove terpin hydrate from 9.41% to 0% and other impurities from 14.06% to 6.78%.