Judul: Pengaruh Jenis Pelarut terhadap Total Terpenoid dan Kapasitas Antioksidan Ekstrak Rimpang Temulawak  (Curcuma zanthorrhiza)
Abstrak: Temulawak (Curcuma zanthorrhiza) merupakan tanaman asli Indonesia mengandung antioksidan dan terpenoid yang mampu menangkal radikal bebas. Sampel rimpang temulawak diekstraksi dengan berbagai jenis pelarut diperlukan untuk mendapatkan senyawa bioaktif temulawak terbaik secara kuantitatif. Penelitian ini bertujuan menentukan pengaruh berbagai jenis pelarut ekstraksi terhadap total terpenoid dan kapasitas antioksidan rimpang temulawak. Sampel diekstraksi dengan gabungan metode sonikasi dan maserasi. Tahapan penelitian meliputi pengujian kadar total terpenoid rimpang temulawak, kemudian dilanjutkan pengujian kapasitas antioksidan dengan metode DPPH, CUPRAC, FRAP, dan ABTS. Hasil penelitian menunjukkan kadar total terpenoid terbesar dihasilkan oleh pelarut H (heksan p.a) sebesar 243.74 ± 8.13a mg UA/g DW dan kapasitas antioksidan terbesar dihasilkan oleh metode FRAP dengan pelarut aseton sebesar 131.25 ± 4.33a. Berdasarkan data dapat disimpulkan terpenoid bukan merupakan komponen utama senyawa antioksidan pada rimpang temulawak karena perbedaan pelarut yang dihasilkan antara data kapasitas antioksidan dan kadar total terpenoid., Temulawak (Curcuma xanthorrhiza) is a plant native to Indonesia that contains antioxidants and terpenoids which are able to ward off free radicals. Temulawak rhizome samples were extracted with various types of solvents to obtain the best bioactive compounds in curcuma quantitatively. This research aimed to determine the effect of various types of extraction solvents on the total terpenoids and antioxidant capacity of curcuma rhizomes. Samples were extracted by a combination of sonication and maceration methods. The research stages included testing the total terpenoid content of curcuma rhizomes, then continued with testing the antioxidant capacity using the DPPH, CUPRAC, FRAP, and ABTS methods. The results showed that the highest total terpenoid content was produced by the H solvent (hexane p.a) of 243.74 ± 8.13a mg UA/g DW and the largest antioxidant capacity was produced by the FRAP method with acetone solvent of 131.25 ± 4.33a. Based on the data, it can be concluded that terpenoids are not the main component of antioxidant compounds in curcuma rhizomes due to differences in the solvent produced between antioxidant capacity data and total terpenoid levels.
Keyword: curcuma, types of solvent, antioxidant, terpenoids

Judul: Pengaruh Pelarut Ekstraksi Rimpang Temu Ireng Metode Microwave Assisted Extraction Terhadap Kandungan Polifenol dan Kapasitas Antioksidan
Abstrak: Temu ireng (Curcuma aeruginosa) merupakan salah satu tanaman yang mengandung senyawa fenolik berupa flavonoid yang berpotensi sebagai antioksidan alami. Pemilihan pelarut ekstraksi yang tepat merupakan hal yang penting untuk mendapatkan metabolit sekunder berkualitas. Penelitian ini bertujuan menentukan pelarut terbaik untuk mengekstrak rimpang temu ireng berdasarkan kadar fenolik total, kadar flavonoid total, dan kapsitas antioksidan dengan metode 2,2-diphenyl-1-pycrilhidrazil (DPPH) dan Ferric Reducing Antioxidant Power (FRAP). Kadar fenolik total diukur menggunakan metode Folin-Ciocalteu dan kadar flavonoid total diukur menggunakan metode Alumunium Klorida. Sampel diekstraksi dengan metode microwave assisted extraction (MAE) dengan pelarut akuades, etanol 50%, metanol 50%, dan aseton 50%. Hasil penelitian menunjukkan pelarut aseton 50% memiliki kadar fenolik total tertinggi (3,10 mg GAE/g BK), sedangkan pelarut metanol 50% menunjukkan kadar flavonoid total tertinggi (4,10 mg QE/g BK), serta kapasitas antioksidan DPPH (1,28 µmol TE/g BK), dan FRAP (12,21 µmol TE/g BK). Pelarut terbaik dalam mengekstrak senyawa aktif pada rimpang temu ireng adalah metanol 50% karena menghasilkan kadar flavonoid total serta kapasitas antioksidan metode DPPH dan FRAP tertinggi., Curcuma aeruginosa is one of the plants that contain phenolic compounds in the form of flavonoids that have the potential to be natural antioxidants. Choosing the right extraction solvent is essential to obtaining quality secondary metabolites. This study aimed to determine the best solvent to extract black rhizomes based on total phenolic content, total flavonoid content, and antioxidant capacity by DPPH and FRAP methods. The total phenolic content was measured using the Folin-Ciocalteu method and the total flavonoid content was measured using the Aluminum Chloride method. The samples were extracted by microwave assisted extraction (MAE) method with aqueous solvents, 50% ethanol, 50% methanol, and 50% acetone. The results showed that 50% acetone solvent had the highest total phenolic content (3,10 mg GAE/g BK), while 50% methanol solvent showed the highest total flavonoid content (4,10 mg QE/g BK), as well as the antioxidant capacity of DPPH (1,28 µmol TE/g BK), and FRAP (12,21 µmol TE/g BK). The best solvent for extracting the active compounds in the rhizomes of black temu is 50% methanol because it produces the total flavonoid levels and the highest antioxidant capacity of the DPPH and FRAP methods.
Keyword: flavonoid, Antioksidan, Pelarut, Fenolik, Temu ireng

Judul: Model Input-output dalam Masalah Network Flow
Abstrak: Production process is a process, which is done by industry, to transform input into output. According to the type of output and its activity, industry can be classified into various sectors, which are connected to each other. Therefore, a model to analyze the connection among sections is needed. The model is known as input-output model (IO model). IO model presents an IO table, which shows informations about the transaction between goods and services in each economic sector. Furthermore, the IO model also shows that the amount of all input is the same as the amount of all output. In this paper, the transaction of each economic sector in IO table is analyzed using network flow theory. The formulated network flow problem implies that each sector represents partly as a producer and also as a consumer. This paper also solves a minimum cost circulation problem.
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