Judul: Antioxidant Capacity and Inhibitory Activity of Matrix Metalloproteinase-1 by Curcuminoids from the tert-Butanol Fraction of Javanese Turmeric
Abstrak: Temulawak mengandung metabolit sekunder kurkuminoid yang dapat berperan sebagai antioksidan dan berpotensi menghambat enzim matriks metalloproteinase-1 (MMP-1) secara simulasi penambatan molekul. Penelitian ini bertujuan mengukur kapasitas antioksidan dan aktivitas inhibisi MMP-1 oleh fraksi tert-butanol rimpang temulawak (Curcuma xanthorrhiza). Metode ekstraksi dilakukan dengan maserasi dengan pelarut etanol 96%. Hasil maserasi difraksinasi menggunakan ammonium sulfat 30% dan tert-butanol:aquades (1:1). Kadar kurkuminoid dianalisis menggunakan High Performance Liquid Chromatography (HPLC) dengan kadar kurkuminoid total sebesar 92,54 mg/g. Kapasitas antioksidan fraksi tert-butanol temulawak diuji menggunakan metode CUPRAC dan ABTS dengan diperoleh berturut-turut sebesar 552,74 ± 39,15 dan 529,94 ± 48,89 µmol AAE/g fraksi. Uji penghambatan MMP-1 menggunakan substrat tiopeptida menunjukkan fraksi tert-butanol temulawak dapat berperan sebagai inhibitor dengan nilai IC50 sebesar 33,12 µg/mL., Javanese turmeric contained secondary metabolites of curcuminoids that can act as antioxidants and potentially inhibit the enzyme matrix metalloproteinase-1 (MMP-1) by simulating molecular docking. This study aimed to measure the antioxidant capacity and inhibitory activity of MMP-1 by tert-butanol fraction of Javanese turmeric rhizome (Curcuma xanthorrhiza). The extraction method was carried out by maceration with 96% ethanol solvent. The results of maceration were liquid:liquid fractionation using 30% ammonium sulfate and tert-butanol:distilled water (1:1). Curcuminoid levels were analyzed using High Performance Liquid Chromatography (HPLC), resulting the total curcuminoid content was 92.54 mg/g. The antioxidant capacity of the temulawak tert-butanol fraction was tested using the CUPRAC and ABTS methods resulting 552.74 ± 39.15 and 529.94 ± 48.89 µmol AAE/g fraction. Matrix metalloproteinase-1 inhibition test using thiopeptide substrate showed temulawak tert-butanol fraction can act as an inhibitor with an IC50 value of 33.12 µg/mL.
Keyword: Temulawak, kolagen, kurkuminoid, matriks metalloproteinase-1

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: Zero-inflated negative binomial models in small area estimation.
Abstrak: The problem of over-dispersion in Poisson data is usually solved by introducing prior distributions which lead to negative binomial models. Poisson data sometime is also suffered by excess zero problems, a condition when data contains too many zero or exceeds the distribution's expectation. Zero Inflated Negative Binomial (ZINB) method can be utilized to solve such problems. This paper demonstrates the adaption of ZINB methods in Small Area Estimation with excess zero data. It is shown that the excess zero problem has substantially influenced the Empirical Bayes (EB) estimates, and the adaption of ZINB methods has improved the precision and reliability of the estimates. Key Words: Small Area Estimation, Zero-Inflation, Poisson-Gamma, Negative Binomial Regression, Empirical Bayes
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