Judul: Pengaruh nisbah bahan baku-pelarut dan suhu ekstraksi terhadap kandungan xanthorrhizol dalam oleoresin temulawak (Curcuma xanthorrhiza ROXB.
Abstrak: Temulawak (Curcuma xanthorrhiza Roxb.) merupakan salah satu tanaman dalam suku temu – temuan (Zingiberaceae) yang memiliki berbagai khasiat. Menurut Sidik at all (1995), temulawak berkhasiat sebagai anti inflamasi, antitumor, mengobati penyakit hipokolesterolemia, mengobati gangguan fungsi hati, memperbaiki fungsi saluran cerna, bersifat antibakteri dan antijamur, dan sebagai antijerawat. Khasiat yang dimiliki oleh temulawak ini tidak lepas dari komponen yang terkandung di dalam rimpang temulawak. Kurkuminoid dan xanthorrhizol diduga sebagai komponen yang memberikan efek farmakologis dari rimpang temulawak. Kurkuminoid merupakan pigmen yang memberikan warna kuning terhadap temulawak, sedangkan xanthorrhizol merupakan salah satu komponen minyak atsiri temulawak. Sejauh ini, temulawak diperdagangkan dalam beberapa bentuk yaitu bentuk rimpang temulawak yang utuh, serbuk temulawak, oleoresin temulawak, dan minyak atsiri temulawak. Penggunaan bahan baku temulawak dalam bentuk rimpang utuh maupun serbuk memiliki beberapa kelemahan, diantaranya adalah bersifat kamba, mudah mengalami perubahan warna dan aroma yang diakibatkan oleh perubahan iklim, mudah terkontaminasi oleh bahan asing, mudah terkontaminasi mikroorganisme, pada tahap aplikasi komponen aktif dihasilkan secara lambat dan tidak terekstrak secara sempurna, dan partikel rimpang mengakibatkan adanya bintik atau noda pada produk akhir (Ravindran at all, 2007). Untuk menutupi kelemahan – kelemahan tersebut, temulawak dapat dimanfaatkan dalam bentuk oleoresin. Oleoresin didefinisikan oleh Glibertson (1971) sebagai campuran antara resin dan minyak atsiri yang diekstrak dari berbagai jenis rempah, baik rempah yang berasal dari buah, biji, daun, kulit, maupun rimpang dengan menggunakan pelarut organik. Pada proses ekstraksi dengan menggunakan pelarut ini, terdapat beberapa faktor yang dapat mempengaruhi efisiensi dan efektifitas ekstraksi. Faktor tersebut diantaranya adalah jenis dan konsentasi pelarut yang digunakan, volume pelarut, suhu ekstraksi, dan ukuran bahan yang diekstrak…
Keyword: Curcuma xanthorrhiza Roxb, Temulawak, Xanthorrhizol, Extraction

Judul: Pengaruh Nisbah Bahan Baku – Pelarut dan Suhu Ekstraksi terhadap Kandungan Xanthorrhizol dalam Oleoresin Temulawak (Curcuma xanthorhiza roxb.).
Abstrak: Temulawak (Curcuma xanthorrhiza Roxb.) belongs to the plant family Zingiberaceae which have various benefits. Sidik et al (1995) described that temulawak can be used as anti-inflammatory, anti-cancer, medicine for many disease like hipokolesterolemia, disorders of liver function, improved gastrointestinal function, for anti-bacterial and anti-fungal, and as anti-acne. Those benefits are related to active components of temulawak rhizhome. Curcuminoids and xanthorrhizol are predicted as components that provides pharmacological effects of temulawak rhizomes. Curcuminoids is the pigment that gives yellow color to temulawak, while xanthorrhizol is one component of the essential oil of temulawak. Temulawak is usually prepared as rhizome slices, powder, oleoresin, and essential oil. Temulawak in form of rhizome slices or powder has some weaknesses, such as bulky, easily to have color and flavor defect caused by climate change, easily contaminated by foreign material and microorganism, slowly produce of active component in the stage application and not completely extracted, and the final product have spots or strain that caused by the rhizome particles (Ravindran et al, 2007). To avoid these weaknesses, temulawak can be processed into temulawak oleoresin. Oleoresin is defined as a mixture of resin and volatile oil extracted from various kinds of herbs, either from the fruit, seeds, leaves, bark, and rhizomes by using organic solvents (Glibertson, 1971). In the process of extraction using this solvent, there are several factors that can affect the extraction efficiency and effectiveness. These factors include the type and concentration of solvent, solvent volume, extraction temperature, and size of the extracted material In this research, extraction temperature and solvent volume were observed to determine their effect on xanthorrhizol content of temulawak oleoresin. The effects of these factors were measured on yield of oleoresin, curcumin content, volatile oil content, solvent residu and the refractive index of the oleoresin. Extraction temperature applied in the experiments were three levels, 30 oC, 40 oC and 50 oC. The solvent volume factor is indicated by the ratio of raw materials to solvent. This study observed three levels of ratio, 1:4, 1:6, and 1:8 using 100 grams of temulawak powder as the ratio basis. Preparation prior to extraction process includes rhizome slicing, drying, and grinding to the size of 60 mesh. Temulawak powder was extracted by stirred maceration using ethanol 96% for four hours, followed by conditioning in room temperature for 24 hours. Temulawak extract was then separated from the solid waste by filtration. The evaporation to remove the solvent from the oleoresin finally conducted using a rotary vacuum evaporator at temperature of 50oC. The yields of temulawak oleoresin are in the range of 9.40% - 17.77% (w / w). The curcumin content is 1.11 to 3.88%, the essential oil content is 3,64 - 11.43%, the xanthorrhizol content equal to peak percentage area of 1.26 - 42.82%, the solvent residu in the oleoresin is 40.950 – 63.750 ppm, and the refractive index value (20/20oC) is ranged from 1.4817 to 1.5198. Statistical analysis of variance at 95% confidence level was used to determine the influence of extraction temperature and raw material-solvent ratio on yield and other experiments parameters. The result showed that
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Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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