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Department of Chemistry Faculty of Mathematics and Natural Sciences Universitas Andalas Kampus Universitas Andalas Limau Manih Padang 25163
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INDONESIA
Jurnal Riset Kimia
Published by Universitas Andalas
ISSN : 1978628X     EISSN : 24768960     DOI : -
Core Subject : Science,
Chemistry
Arjuna Subject : -
Articles 551 Documents
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Sintesis Codoped-Sr2TiO4 Fasa Ruddlesden-Popper dengan Metoda Lelehan Garam dan Sifat Hantaran Listriknya Elan Mulia; Ayu Sabrina; Dila Kartika Aprianti; Nova Andriani; Zulhadjri Zulhadjri; Yulia Eka Putri
Jurnal Riset Kimia Vol. 11 No. 2 (2020): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v11i2.358

Abstract

In this research, undoped-Sr2TiO4 and codoped-Sr2TiO4 Ruddlesden-Popper (RP) phase compounds have been synthesized with mole variations of Sr:Ti and dopants. Double substitution with Sm3+ for Sr2+ sites and Nb5+ for Ti4+ sites forming Sr2-xSmxTi1-yNbyO4 (x = 0.0125; 0.025; 0.05; 0.1 and y = 0.0125) aimed to increase the number of electrons carrier, so that the electrical conductivity enhanced. The XRD patterns showed that the highest purity of prepared Sr2TiO4 RP phase sample was obtained at the mole ratio of Sr:Ti of 2:1 with specific peaks at 2θ: 31.35°, 46.73°, and 57.33°. Then, this mole ratio was used to prepare the codoped-samples, and the XRD patterns showed the Sr1.95Sm0.05Ti0.9875Nb0.0125O4 sample has the highest purity. SEM images showed that the undoped-Sr2TiO4 and codoped-Sr2TiO4 samples have a plate-like particles with micrometer size. The electrical conductivity of Sr1.95Sm0.05Ti0.9875Nb0.0125O4 sample was measured to be a 17-fold increase compared to that of undoped-Sr2TiO4 sample. 
Penentuan Resistivitas Tak-Terkompensasi Cairan Ion Berbasis Imidazol dengan Metode EIS: Pengaruh Panjang Alkil dan Perbedaan Anion Aep Patah; Yulia Rachmawati; Riyadini Utari; Achmad Rochliadi
Jurnal Riset Kimia Vol. 11 No. 2 (2020): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v11i2.359

Abstract

Ionic liquids have interesting properties because they have several advantages compared to conventional organic solvents, such as high thermal stability, high viscosity, good solvent properties, non-flammable, and non-volatile. In electrochemistry, ionic liquids can be used as solvents without the addition of electrolytes. However, ionic liquids still have resistivity properties (uncompensated resistance), thus ohmic drop measurements are needed for a potential correction. Imidazole-based ionic liquids, which are known for their high conductivity and commonly used as a solvent, have been measured of their resistivity as a function of temperature, and type of their cations/anions. Electrochemical Impedance Spectroscopy (EIS) method was chosen to measure the resistivity of ionic liquids and Bode plot was generated for the analysis of the results. The measured resistivities of ionic liquids are in the range of 420 to 1500 ohm. It is concluded that the resistivity of the imidazole-based ionic liquid is influenced by the size of their constituent ions, the viscosity, and the resistance is decreased with increasing temperature.
Analysis of The Essential Oil from Lantana camara Leaves and Its Cytotoxic Potential Against T-47D Breast Cancer Cells Suryati Suryati; Enda Desriansyah Aziz; Mai Efdi; Fatma Sri Wahyuni; Dira Hefni
Jurnal Riset Kimia Vol. 12 No. 1 (2021): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i1.364

Abstract

Lantana camara Linn is a family of Verbenaceae which grows wild and is widespread in various both tropical and sub-tropical countries. Isolation essential oil of the L. camara leaves extracted by hydrodistillation and were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The results of GC-MS analysis show isocaryophyllene (14.39%), ρ-cymene (8.17 %), β-cubebene (7.8 %), α-pinene (7.64 %), and β-elemene (5.51 %) as the main compound. The cytotoxic activity of the isolated essential oil was highly toxic both to Artemia salina shrimp larvae (LC50 15.92 µg/mL) and to breast cancer cells T-47D (IC50 10.67 µM).
Molecular Docking and Molecular Dynamic Simulation of 1,5-Benzothiazepine Chalcone Derivative Compounds as Potential Inhibitors for Zika Virus Helicase Neni Frimayanti; Musyirna Rahmah Nasution; Elsa Etavianti
Jurnal Riset Kimia Vol. 12 No. 1 (2021): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i1.365

Abstract

Zika virus caused of the emerging infections characterized by fever, Guillain-Barré syndrome (GBS) for adults. In the current work, we aimed to study the binding orientation of 1,5-benzothiazepine compounds as new potential agent against Zika virus inhibitor through molecular docking and molecular dynamic simulation. Since, 1-5-Benzothiazepines are particular interest for drug discovery and they also has some biological activities. However, their antiviral activities and in silico studies of the binding to their biological targets have not been extensively investigated. Molecular docking study of 1,5-benzothiazepine chalcone derivatives compounds with protein target 5GJB (PDB ID) and this protein was taken from the crystallographic structure. In this study, twelve 1,5-benzothiazepine chalcone derivative compounds were docked to the protein with the grid box along x, y and z radius of 26.85, 28.17 and 24.43 Å, respectively. Suramin was used as positive control. Thus, it can be used as a reference for design new inhibitors for Zika virus helicase. Based on the docking results, it is observed that compounds MA3 and MA8 are estimated to have activity as inhibitors for Zika virus helicase with binding free energy values of -4.6490 and -4.9291 kcal/mol, respectively. MA3 and MA8 were also stable during the MD simulations with the hydrogen bonding are still maintained before and after MD simulation. Furthermore, both of these compounds can be used an early stage for drug design and drug delivery process.
Analisis Kimia dan Kualitas Air Hujan di Kota Palu Sebagai Penyebab Terjadinya Hujan Asam Solih Alfiandy; Donaldi Sukma Permana; Muharam Syam Nugraha; Isna Jutika Aulia Putri
Jurnal Riset Kimia Vol. 12 No. 1 (2021): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i1.368

Abstract

Acidic compounds such as sulfur dioxide (SO2) and nitrogen oxides (NOx), which are generally emitted into the atmosphere by human activities from burning fossil fuels, motor vehicles and industry, react with water and oxygen to produce acidic rain that falls to the earth's surface. This study aims to investigate the quality of rainwater chemical compounds at the Mutiara Palu Meteorological Station using 282 samples derived from the BMKG Air Quality Database during February 1993 – January 2020. The method used are descriptive analysis and correlation analysis to determine the relationship between chemical compound reactions that occur in the rainwater in Palu City. The results showed that the chemical compounds in rainwater in Palu City were dominated by strong acid compounds in the form of Cl-, SO42-, and NO3- compounds with a percentage of 63% and the most dominant quality was in the acidic rain category with a pH value below 5.6, as much as 55.7%. Chemical compounds contained in rainwater in Palu City are mineral compounds that originated from natural form of minerals, particularly from sea salt. The relationship between chemical compounds contained in rainwater has varied values and is in the low to moderate category. In general, the results indicate that the quality of rainwater in Palu City is low and not recommended for health and the environment.
Sintesis Mg2+ Doped ZnO dengan Penambahan Albumen Ayam Ras Menggunakan Gabungan Metode Sol-Gel dan Sonokimia Sherly Kasuma Warda Ningsih; Umar Kalmar Nizar; Bahrizal Bahrizal; Edi Nasra; Siti Fatimah Mutiara R
Jurnal Riset Kimia Vol. 12 No. 1 (2021): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i1.374

Abstract

Mg2+ doped ZnO has been successfully synthesized using a combination of sol-gel and sonochemical methods. Zinc acetate dihydrate was used as a precursor, magnesium chloride hexahydrate as a source of Mg dopant, methanol as a solvent, and chicken albumen was used as an additive to replace monoethanolamine. The sol was heated at 110 °C for 1 hour. The gel formed was calcined at 600 °C for 3 hours. FTIR analysis shows that the absorbance band around 400-450 cm-1 indicates Mg-O stretching, the absorbance band around 500-550 cm-1 indicates Zn-O stretching, the absorbance band around 400-550 cm-1 shows Zn-O-Mg bonds. Mg. Measurements with UV-DRS, obtained the smallest ZnO band gap value doped Mg2+ around 2.7 eV with the addition of 10 mL albumen. The resulting crystal structure was wurtzite with crystal size with the addition of 10, 20, 30, 40 and 50 mL albumen were 25.22-55.91 nm, 32.99-75.87 nm, 45.92-83.91 nm, 45.92-75.89 nm and 46.15-71.47 nm respectively. SEM photo of Mg2+ doped ZnO with the addition of 10 mL of albumen has a hexagonal surface morphology.
Pengaruh Penambahan Surfaktan pada Fermentasi Tandan Kosong Kelapa Sawit dengan Praperlakuan Uap Air Panas Bertekanan dengan Katalis Asam Maleat Sita Heris Anita; Devi Nury Ashrianis; Widya Fatriasari
Jurnal Riset Kimia Vol. 12 No. 1 (2021): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i1.379

Abstract

Oil palm empty fruit bunch (OPEFB) has high potency to be converted into second generation bioethanol production. OPEFB pretreated liquid hot water (LHW) assisted maleic acid (MA) pretreatment was used as substrate in simultaneous saccharification fermentation (SSF). This pretreatment was conducted at 180 °C for 70 min by using 1.5% (w/v) MA acid concentration with material and liquid ratio of 1:14. Subsequently, the pretreated samples were fermented by addition of surfactant, polyethylene glycol (PEG) 4000 and amphiphilic lignin derivatives (A-LD) using Kluyveromyces marxianus InaCC Y119 yeast at temperature of 38 °C for 89 h. Before SSF, pretreated OPEFB was pre hydrolyzed by cellulase enzyme with enzyme loading 30 FPU/g at 50 °C for 3 h. Fermentation filtrate was taken at 0, 24, 48, 72, dan 89 h as much as 1.5 mL for reducing sugar and ethanol content determination. The surfactant addition can enhance reducing sugar and also ethanol content compared to control. The highest ethanol content of 1.251 g/L was found at fermentation of OPEFB pretreated MA with PEG 4000 surfactant at 89 h.
Uji Aktivitas Antioksidan dan Fenolik Total Fraksi Etil Asetat Daun Sembung (Blumea balsamifera (L.) DC) Azimatur Rahmi; Tika Afriani; Linda Hevira; Wike Widiawati
Jurnal Riset Kimia Vol. 12 No. 2 (2021): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i2.383

Abstract

The aim of this study is to investigate antioxidant activity and total phenolic content of ethyl acetate fraction of Sembung leaves. Sembung (Blumea balsamifera L.) is a plant that has the potential as an antioxidant because it contains secondary metabolites of alkaloids, steroids, flavonoids, saponins, and phenolic compounds. In this study, antioxidant activity was tested by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) for free radical scavenging activity assay. Evaluation of total phenolic content was tested by using the Folin-Ciocalteau method. The results showed that the ethyl acetate fraction of Sembung leaves possess showed medium antioxidant activity with IC50 valueof 221.821 compare with reference standard ascorbic acid with IC50 value 68.25 ppm. The ethyl acetate fraction of Sembung leaves has a total phenolic content of 161.101 mg GAE/g. This study provided that Blumea balsamifera leaves possess antioxidant.
Activated Carbon Addition Methods on the Pre-impregnation Process of Co-Mo in Y-Zeolite Ultra Stable: A Properties Exploration and Enhancement of Metals Loaded Yuniawan Hidayat; Khoirina Dwi Nugrahaningtyas; Priska Julia Hendrastuti
Jurnal Riset Kimia Vol. 12 No. 2 (2021): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i2.384

Abstract

The amount of loaded Co-Mo metal on the Y-Zeolite Ultra Stable (USY) was increased by the addition of activated carbon in the pre-impregnation process. USY modification was done by adding activated carbon to USY as much as 10 wt%. The process of adding activated carbon is carried out by three methods, i.e., grinding with sucrose binder (ACU1), without sucrose (ACU2), and conducting by ball milling (ACU3). Wet impregnation method was employed to disperse the Co and Mo, sequentially. Composites were characterized using Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), and surface area analyzer (SAA). Metal dispersions were observed by X-ray fluorescence (XRF). The FTIR suggests an interaction between USY and activated car-bon, while the XRD result indicated the none structural transformation of USY zeolite. The SAA analysis showed an increased total pore radius with the activated carbon addition. The XRF confirmed the increasing of total metals dispersion of 6.25% (ACU1); 5.48%(ACU2); 5.18% (ACU3); compare to USY origin with 3.28% metals loaded.
Penggunaan ZnO/Zeolit Sebagai Katalis Dalam Degradasi Tartrazin Secara Ozonolisis Zilfa Zilfa; Safni Safni; Febi Rahmi
Jurnal Riset Kimia Vol. 12 No. 1 (2021): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i1.387

Abstract

An investigation on modification of natural zeolite with ZnO for the degradation of tartrazine. In this study, ZnO as a semiconductor is modified into a natural zeolite as support to form ZnO/zeolite that can increase the efficiency degradation of tartrazine. Further, the formed catalyst was added to tartrazine by determining the variation in ozonolysis time, the amount of addition of the catalyst, and the addition of a catalyst time. The results of degradation were determined by UV-Vis spectrophotometer at 424 nm. The result showed that the percentage of degradation obtained on each catalyst in the degradation. The resulted percent degradation of 20 ml of tartrazine at concentration of 15 mg/L using 20 mg ZnO/zeolite was 56.80%, while using 0.77 mg ZnO was 42.25%, and with the addition of 19.23 mg of Zeolite was 31.18%, all of that condition was proceeded by 40 minutes of ozonolysis. Thus, the result indicates that the ZnO/zeolite catalyst can increase percentages of tartrazine degradation by ozonolysis. It is known that the catalyst ZnO/zeolite is very effective in increasing the degradation of tartrazine. Analysis of tartrazine compounds using fourier-transform infrared spectroscopy (FTIR) after degradation changes in wavenumber indicates that there is a breaking of the bonds of tartrazine compounds. Characterization of ZnO/zeolite catalyst using FTIR, X-Ray diffraction (XRD) and scanning electron microscope (SEM), in each spectrum there was no shift, indicating that there is no change in ZnO/zeolite structure

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