Ria Armunanto
Austrian-Indonesian Centre for Computational Chemistry, Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281

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ANALISIS HUBUNGAN KUANTITATIF STRUKTUR DAN AKTIVITAS ANTITOKSOPLASMA SENYAWA ANALOG KUINOLON MENGGUNAKAN DESKRIPTOR TEORITIK Thahir, Iqmal; Fatimah, Nur Fitri; Armunanto, Ria
Jurnal Sains dan Terapan Kimia Vol 6, No 2 (2012)
Publisher : Jurnal Sains dan Terapan Kimia

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Abstract

Analisis Hubungan Kuantitatif Struktur dan Aktivitas (HKSA) antitoksoplasmadari 24 senyawa analog kuinolon telah dilakukan berdasarkan analisis regresimultilinear. Jenis deskriptor yang digunakan adalah parameter teoritik hasilperhitungan meliputi deskriptor-deskriptor lipofilisitas (log P), sterik (indeksHarary dan indeks Randic), dan elektronik (muatan bersih atom dan selisihenergi HOMO-LUMO). Terhadap setiap senyawa ditentukan nilai log P danindeks sterik, kemudian perhitungan struktur elektronik dilakukan denganmetoda semiempirik AM1 melalui tahapan optimasi geometri. Data aktivitasantitoksoplama (IC50) didapatkan dari literatur dan dinyatakan sebagai nilai log1/IC50. Analisis MLR dilakukan terhadap data awal yang dipisahkan secara acakmenjadi data fitting dan data uji. Persamaan QSAR akhir diperoleh dengananalisis terhadap data total. Hasil penelitian ditunjukkan dengan modelpersamaan QSAR terpilih yang dipresentasikan dalam persamaan:            - 9 56. 172 007. 5.log1/ 83,287 0,522. E - 225,7.qC 7,963.qC 4,285.qX 32,329.qC1 250 4 5 8 9q qICdengan n = 24; r = 0,942; r2 = 0,887; SE = 0,254; Fhit/Ftab = 5,586Kata Kunci: quinolon, QSAR, antitoksoplasm
Optimasi Produksi dan Sifat Fungsional Asap Cair Kayu Karet Darmadji, Purnama; Oramahi, H.A.; Armunanto, Ria
Agritech Vol 20, No 3 (2000)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/agritech.13686

Abstract

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Aktivitas Antioksidan Kulit Biji Kakao dari Hasil Penyangraian Biji Kakao Kering pada Derajat Ringan, Sedang dan Berat Utami, Ratri Retno; Supriyanto, Supriyanto; Rahardjo, Sri; Armunanto, Ria
Agritech Vol 37, No 1 (2017)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/agritech.10454

Abstract

Cocoa bean shell is waste from chocolate industry that containing polyphenol 5.78 % and can be used as natural antioxidant source. The most important step in cocoa processing is roasting. Roasting is needed for developing the chocolate flavor. Chocolate industries do their roasting with low, medium and high degree, depend on product’s necessity. The objective of this research is to determine the effect of roasting degree toward cocoa bean shell antioxidant activity. Cocoa bean roasted at low degree (110 ºC for 60 minutes), medium (140 ºC for 40 minutes) and high (190ºC for 15 minutes). Cocoa bean shell polyphenol was extracted with acetone 70 %. Yield, total phenolic, DPPH free radical scavenging activity as IC50 and inhibition of linoleic acid oxidation was analyzed from crude polyphenol extract. The result shows that the increasing of roasting temperature leads to low yield. Cocoa bean shell polyphenol extract with high roasting degree has the lowest yield (8.07 % b/b). While cocoa bean shell polyphenol extract using medium roasting degree has the highest total phenolic and DPPH free radical scavenging activity of 21.23 ± 0.39 mg GAE/g dry extract and IC50 74.31 ± 0.72 μg/mL, respectively. Cocoa bean shell polyphenol extract is able to inhibit the linoleic acid oxidation. Roasting enhance the inhibition of linoleic acid oxidation compared to extract without roasting about 6%. For the future study, it is needed to identify the cocoa bean shell antioxidant compound during roasting. ABSTRAKKulit biji kakao merupakan limbah dari industri pengolahan cokelat yang mengandung polifenol sebesar 5,78 %, sehingga berpotensi untuk dimanfaatkan sebagai sumber senyawa antioksidan alami. Tahapan penting dalam pengolahan biji kakao kering adalah penyangraian yang berguna untuk pengembangan citarasa khas cokelat. Industri pengolahan cokelat melakukan penyangraian dengan derajat ringan, sedang dan berat, berdasarkan produk yang dikehendaki. Penelitian ini bertujuan untuk mengetahui pengaruh derajat penyangraian terhadap aktivitas antioksidan kulit biji kakao. Biji kakao kering disangrai pada derajat ringan (110 ºC selama 60 menit), sedang (140 ºC selama 40 menit) dan berat (190 ºC selama 15 menit). Polifenol kulit biji kakao diekstrak menggunakan aseton 70 %. Ekstrak polifenol kering dianalisis rendemen, total fenolik, RSA DPPH yang dinyatakan sebagai IC50 dan penghambatan oksidasi asam linoleat. Hasil penelitian menunjukkan bahwa semakin tinggi suhu penyangraian, rendemen yang diperoleh semakin kecil. Ekstrak polifenol kulit biji kakao dengan penyangraian derajat berat mempunyai rendemen paling kecil (8,07 % b/b). Ekstrak polifenol kulit biji kakao dengan penyangraian derajat sedang mempunyai total fenolik dan aktivitas antioksidan penangkap radikal DPPH paling tinggi yaitu sebesar 21,23 ± 0,39 mg EAG/g ekstrak kering dan nilai IC50 74,31 ± 0,72 μg/mL. Ekstrak polifenol kulit biji kakao mampu menghambat oksidasi asam linoleat. Penyangraian meningkatkan aktivitas penghambatan oksidasi asam linoleat sebesar 6 % bila dibandingkan dengan ekstrak polifenol kulit biji kakao tanpa penyangraian. Perlu dilakukan penelitian selanjutnya untuk identifikasi senyawa antioksidan kulit biji kakao dari hasil penyangraian.
STUDY ON ANTI-HIV ACTIVITY OF DIARYLANILINE DERIVATIVES USING QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIP (QSAR) Arief, Ihsanul; Armunanto, Ria; Setiaji, Bambang
Indonesian Journal of Chemistry Vol 13, No 2 (2013)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (296.485 KB) | DOI: 10.22146/ijc.21295

Abstract

Study on anti-HIV activity of diarylaniline derivative compounds by using quantitative structure-activity relationship (QSAR) has been done. The compounds structure and their anti-HIV activities were obtained from literature. Molecular and electronic parameters were calculated by Austin Model 1 (AM1), Parameterized Model 3 (PM3), Hartree-Fock (HF), and density functional theory (DFT) methods. QSAR analysis was performed using multilinear regression method. The result shows that HF method can produce the best model as follows:log EC50 = 46.418 + (99.360 × qC4) - (67.189 × qC9) - (278.869 × qC15) + (782.466 × qC19) - (127.463 × qO7)n = 20; r2 = 0.815; SEE = 0.393; Fcal/Ftab = 4.185; PRESS = 2.160Those model can predict a good inhibitory activity (log EC50) value of -0.3359 to compound N1-(4′-Cyanophenyl)-5-(4″-cyanovinyl-2″,6″-dimethyl-phenoxy)-4-hydroxyethylbenzene-1,2-diamine).
Theoretical Study on the Extraction of Alkaline Earth Salts by 18-Crown-6: Roles of Counterions, Solvent Types and Extraction Temperatures Hadisaputra, Saprizal; Canaval, Lorenz R; Pranowo, Harno Dwi; Armunanto, Ria
Indonesian Journal of Chemistry Vol 14, No 2 (2014)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (576.723 KB) | DOI: 10.22146/ijc.21259

Abstract

The roles of counterions, solvent types and extraction temperatures on the selectivity of 18-crown-6 (L) toward alkaline earth salts MX2 (M = Ca, Sr, Ba; X = Cl-, NO3-) have been studied by density functional method at B3LYP level of theory in gas and solvent phase. In gas phase, the chloride anion Cl- is the preference counterion than nitrate anion NO3-. This result is confirmed by the interaction energies, the second order interaction energies, charge transfers, energy difference between HOMO-LUMO and electrostatic potential maps. The presence of solvent reversed the gas phase trend. It is found that NO3- is the preference counterion in solvent phase. The calculated free energies demonstrate that the solvent types strongly change the strength of the complex formation. The free energies are exothermic in polar solvent while for the non polar solvent the free energies are endothermic. As the temperature changes the free energies also vary where the higher the temperatures the lower the free energy values. The calculated free energies are correlated well with the experimental stability constants. This theoretical study would have a strong contribution in planning the experimental conditions in terms of the preference counterions, solvent types and optimum extraction temperatures.
EXTRACTION OF STRONTIUM(II) BY CROWN ETHER: INSIGHTS FROM DENSITY FUNCTIONAL CALCULATION Hadisaputra, Saprizal; Pranowo, Harno Dwi; Armunanto, Ria
Indonesian Journal of Chemistry Vol 12, No 3 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (740.602 KB) | DOI: 10.22146/ijc.21332

Abstract

The structures, energetic and thermodynamic parameters of crown ethers with different cavity size, electron donating/withdrawing substituent groups and donor atoms have been determined with density functional method at B3LYP level of theory in gas and solvent phase. Small core quasi-relativistic effective core potentials was used together with the accompanying SDD basis set for Sr2+ and DZP basis set was used for crown ether atoms. Natural bond orbital (NBO) analysis was evaluated to characterize the distribution of electrons on the complexes. The interaction energy is well correlated with the values of Strontium charge after complexation, the second order interaction energies (E2) and HOMO-LUMO energy gab (∆Egab). The interaction energy and thermodynamics parameters in gas phase are reduced in solvent phase as the solvent molecules weaken the metal-crown ether interaction. The thermodynamic parameters indicated that less feasibility to extract Sr2+ ion directly from pure water without presence of organic solvent. The theoretical values of extraction energy for Sr(NO3)2 salt from aqueous solution in different organic solvent is validated by the experimental trend. This study would have strong contribution in planning the experiments to the design of specific host ligand and screening of solvent for extraction of metal ion.
Structure and Dynamics of Zr4+ in Aqueous Solution: An Ab Initio QM/MM Molecular Dynamics Study Suwardi, Suwardi; Pranowo, Harno Dwi; Armunanto, Ria
Indonesian Journal of Chemistry Vol 15, No 2 (2015)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (443.324 KB) | DOI: 10.22146/ijc.21209

Abstract

A QM/MM molecular dynamics (MD) simulation has been carried out using three-body corrected pair potential to investigate the structural and dynamical properties of Zr4+ in dilute aqueous solution. Structural data in the form of radial distribution function, coordination number distribution, and angular distribution function were obtained. The results indicate eight water molecules coordinate to zirconium ion and have two angles of O-Zr4+-O, i.e. 72.0° and 140.0° with a Zr4+-O distance of 2.34 Å. According to these results, the hydration structure of Zr4+ ion in water was more or less well-defined square antiprismatic geometry. The dynamical properties have been characterized by the ligand’s mean residence time (MRT) and Zr4+-O stretching frequencies. The inclusion of the three-body correction was important for the description of the hydrated Zr4+ ion, and the results indicated in good agreement with experimental values.
EFFECT OF SCANDIUM ON HIDROGEN DISSOCIATION ENERGY AT MAGNESIUM SURFACE: AB INITIO DFT STUDY Sutapa, I Wayan; Armunanto, Ria; Wijaya, Karna
Indonesian Journal of Chemistry Vol 10, No 2 (2010)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (304.266 KB) | DOI: 10.22146/ijc.21458

Abstract

The dissociative chemisorption of hydrogen on both pure and Sc-incorporated Mg(0001) surfaces have been studied by ab initio density functional theory (DFT) calculation. The calculated dissociation energy of hydrogen molecule on a pure Mg(0001) surface (1.200 eV) is in good agreement with comparable theoretical studies. For the Sc-incorporated Mg(0001) surface, the activated barrier decreases to 0.780 eV due to the strong interaction between the molecular orbital of hydrogen and the d metal state of Sc. This could explain the experimentally observed improvement in absorption kinetics of hydrogen when transition metals have been introduced into the magnesium materials.   Keywords: Dissociation, Adsorption, Chemisorptions, DFT, Magnesium
CYCLIZATION AND HYDROGENATION OF (+)-CITRONELLAL TO MENTHOLS OVER ZnBr2 AND Ni CATALYSTS SUPPORTED ON γ-Al2O3 Iftitah, Elvina Dhiaul; Muchalal, M.; Trisunaryanti, Wega; Armunanto, Ria
Indonesian Journal of Chemistry Vol 10, No 2 (2010)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1114.243 KB) | DOI: 10.22146/ijc.21461

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Two steps transformation of (+)-citronellal, cyclization and hydrogenation, on ZnBr2/γ-Al2O3 and Ni/γ-Al2O3 catalyst have been realized with the selectivity to cyclization products (isopulegols) was very high (yield up to ~92.58%) over ZnBr2/γ-Al2O3 under mild condition (90 °C and 1 atm nitrogen atmosphere) with high Brønsted acid concentration, while at the same time very low cyclization rates were achieved over Ni/γ-Al2O3 with low or no Brønsted acidity, respectively. The highest cyclization rates were observed over Ni/ZnBr2/γ-Al2O3 under mild condition (90 °C and 1 atm hydrogen atmosphere). The second step transformation towards cyclization products, hydrogenation to menthols, was performed with Ni/γ-Al2O3 under hydrogen atmosphere. Surprisingly the one-step transformation of (+)-citronellal into menthols was investigated over Ni/γ-Al2O3 with yield ~84% under hydrogen atmosphere (90 °C, 1 atm) by exploiting the presence of acidic and hydrogenation sites on the catalyst surface. On the Ni/γ-Al2O3 catalyst it was found that the cyclization of (+)-citronellal to isopulegols occurs on the surface of the support. In the presence of the noble metal, the isopulegols are further hydrogenated to the menthols.   Keywords: cyclization, hydrogenation, citronellal, isopulegol, menthol
QSAR STUDY OF XANTHONE DERIVATIVES AS ANTI PLASMODIAL AGENTS Amanatie, Amanatie; Jumina, Jumina; Mustofa, Mustofa; Hanafi, M.; Armunanto, Ria
Indonesian Journal of Chemistry Vol 10, No 3 (2010)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (177.856 KB) | DOI: 10.22146/ijc.21443

Abstract

Xanthones and their derivatives have been reported to exhibit inhibitory activities towards Plasmodium falciparum. To provide deep insight into the correlation between inhibitory activities and structures of xanthones, linear regression method was employed to establish QSAR models for 16 xanthone derivatives that have diverse structures. The accuracy and predictive power of the proposed QSAR model were verified by semi empirical PM3 method, optimation, and validation. The result showed that the best model is model 3 i.e. Log 1/IC50 = Σ (-1.446)qO(7)+ (-8.775)q.C(12) + (-10.592)qC(13) + 1,979; Y = PRESS = 1.124192.