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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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KAJIAN TEORITIS KEMAMPUAN CAPPING KATEKIN, KATEKU TANAT DAN QUARSETIN TERHADAP NANOPARTIKEL PERAK DENGAN MENGGUNAKAN METODA DFT-B Syukri Arief; Emriadi -; Ade Saputra
Jurnal Riset Kimia Vol. 9 No. 1 (2015): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v9i1.256

Abstract

Interdiffusion mechanism of catechin, catechutannic acid and quercetin are studied by using DFT-B method. But before conducting these experiment, we perform molecular dynamic simulations to find adsorption models probability of each compound. Two models adsorption of quarcetin, four models for catechin and three models for catechutannic acid have been obtained from molecular dynamic simulations. Quantum parameter of each compound, energy and properties adsorption models have been calculated and discussed. The theoretical results were found to be consistent with the experimental data reported. Futhermore, optimization adsorption model samples show that all of adsorbents have weak bonds on the surface of silver nanoparticles. The mechanism can be classified as strong physisorption, so that catechin, catechutannic acid and quercetin can be categorized as good capping agent in synthesis of silver nanoparticles.
PEMBUATAN DAN KARAKTERISASI KATALIS TIO2/KARBON AKTIF DENGAN METODE SOLID STATE Upita Septiani; Mega Gustiana; Safni -
Jurnal Riset Kimia Vol. 9 No. 1 (2015): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v9i1.257

Abstract

Composite catalyst of TiO2/Activated Carbon (TiO2/AC) had been synthesized with successfully by solid-state method. Synthesis was done by varying the addition of AC 5%, 10% and 15% of the mass of TiO2 was used. Composite catalyst was calcinated at temperature 400°C and characterized by Fourier Transform Infra-Red (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). FTIR spectrum show that the absorption appearedin the regionof C=C at wave number 1600-1800 cm-1, that assumed from AC. From XRD we can see that with variated of AC do not given different XRD patterns significantly, crystal structure of composite catalyst is anatase. SEM images showed that AC prevented the aglomeration of TiO2 that would expand surface area and increased catalytic activity of TiO2.
Identifikasi Senyawa Metabolit Sekunder, Uji Antimikroba dan Antioksidan Ekstrak Akar Gantung Hornstedtia Scyphifera Var. Fusiformis Holttum (Sijangkang) Adlis Santoni; Mai Efdi; Akmel Suhada
Jurnal Riset Kimia Vol. 10 No. 2 (2019): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v10i2.264

Abstract

Hornstedtia scyphifera var. fusiformis Holttum is endemic plant of Zingiberaceae family that distributed in Sumatera. Hornstedtia scyphifera var. fusiformis Holttum contained some secondary metabolite such as phenolic, saponin, triterpenoid and alkaloid. The biological activity of methanol, ethyl acetate, and n-hexane extracts from Hornstedtia scyphifera var. fusiformis Holttum suspended roots was tested for antibacterial and antioxydant activity. Antioxidant activity was analized by DPPH method. The antibacterial activity  was tested by used disk difussion method againts Staphylococcus aureus bacteria (gram-positive bacteria) and Escherichia coli (gram-negative bacteria). Almost all of Hornstedtia scyphifera var. fusiformis Holttum suspended roots extract were given antibacterial activity, nonetheless the biggest inhibition zone of Escherichia coli that was inhibited by n-hexane and ethyl acetate extracts which have inhibtion zone 10 mm at  concentration 500 mg/L and also againts Staphylococcus aureus, the biggest inhibition by ethyl acetate and n-hexane extracts which have inhibition zone 10.30 mm at concentration 500 mg/L. Among all extracts tested, methanol extract of the possessed moderate free radical scavenging activity with IC50 = 51.89 mg/L.
PREPARASI DAN MODIFIKASI KIMIA STRUKTUR KITOOLIGOSAKARIDA-2,5-ANHIDRO-D-MANNOFURANOSA (KOSAMF) DARI KITOSAN SERTA UJI ANTIBAKTERI TERHADAP Staphylococcus aureus DAN Escherichia coli Emil Salim; Hasnirwan -; Sanusi Ibrahim; Afrizal -
Jurnal Riset Kimia Vol. 9 No. 2 (2016): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v9i2.279

Abstract

Kitooligosakarida-2,5-anhidro-D-mannofuranosa (KOSamf) dipersiapkan dengan derajat polimerisasi tertentu melalui reaksi nitrous deaminasi dari kitosan parsial N-deasetilasi. KOSamf kemudian diubah menjadi turunan KOSamf dengan mengkopling gugus aldehid yang terdapat pada unit 2,5-anhidro-D-mannofuranosa (amf). KOSamf dengan 3,5-dikloroanilin dan NaBH3CN dalam pelarut buffer ammonium asetat direaksikan melalui metoda one-pot aminasi reduktif untuk menghasilkan turunan KOSamf yang berpotensi sebagai senyawa antibakteri dan antijamur. Struktur kimia dari turunan KOSamf yang telah disintesis dikarakterisasi dengan Spektroskopi FT-IR dan NMR. Senyawa turunan KOSamf memiliki aktivitas sebagai antibakteri terhadap bakteri Staphylococcus aureus dengan zona inhibisi 12,5 mm dan bakteri E. coli dengan zona inhibisi 10,5 mm.
EKSTRAKSI DAN IDENTIFIKASI SENYAWA ANTOSIANIN DARI JANTUNG PISANG RAJA (Musa x paradisica L.) SERTA UJI AKTIVITAS ANTIOKSIDANNYA Jessica Alvionita; Djaswir Darwis; Mai Efdi
Jurnal Riset Kimia Vol. 9 No. 2 (2016): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v9i2.284

Abstract

Anthocyanin coumpound have been successfully extracted from plantain bud (Musa x paradisiaca L) which can used as natural colorant and antioxidant. Coumpound anthocyanin exracted using maceration method with solvent ethanol that has been acidified with acetic acid and citric acid until pH 1,5. The extract anthocyanin is identified by UV-Vis spectrophotometer (260-800 nm) and retrieved two peaks that is 277 nm (UV) and 533 nm (Visible). Further treatment is carried out with KCKT-DAD at a wavelength 516 nm. Anthocyanin treatment given temperature and pH. Total anthocyanin monomeric obtained for ethanol + acetic acid was 30,22 mg/L; ethanol + citric acid was 18,20 mg/L. The warming influence of the anthocyanin compound lead to degradation of color is highest for ethanol + acetic citric on temperature 100oC with percentage degradation of 61,97 %. The antioxidant activity of the extract was measured by 1,1- difenil-2-pikrilhidrazil (DPPH) the result showed that the anthocyanin extracts from Plantain bud has antioxidant activity ethanol + acetic citric acid extract is very active as an antioxidant with IC50  values of 3,74 mg/L.
PROSES ULTRAFILTRASI UNTUK PENJERNIHAN SARI BUAH MARKISA (Passiflora quadrangularis) DENGAN MEMANFAATKAN MEMBRAN KERAMIK Refinel -; Olly Norita Tetra; Roza Melia Usmita
Jurnal Riset Kimia Vol. 9 No. 2 (2016): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v9i2.285

Abstract

Ultrafiltration of passion fruit juice using variation thickness of ceramic membrane has been done.  The result shows that aquades flux value in 25 minutes for membrane 1.5; 2.0; 2.5; 3.0; and 3.5 mm is 17.0135; 19.1947; 10.9061; 10.9061 and 4.3624 L/h m2. Whereas passion fruit juice in same time for membrane 1.5; 2.0; 2.5 mm is 8.2886; 5.6712 and 4.3624 L/h m2. For membrane 3.0 and 3.5 mm it has not been done because flux value are too small that indicate fouling. Physical and chemical properties parameter in ultrafiltration of passion fruit juice obtained for turbidity and color very different between passion fruit juice before and after ultrafiltration, whereas reducing sugar and vitamin C are not significant different between passion fruit juice before and after ultrafiltration. Determination rejection coefficient value of membrane for turbidity, color  relatively significant whereas for reducing sugar and vitamin C are relatively not significant.
SINTESIS LAPISAN TIPIS TiO2 BERPORI YANG DIMODIFIKASI OLEH NITROGEN DENGAN METODE PEROKSO SOL-GEL, KARAKTERISASI DAN APLIKASINYA SEBAGAI MATERIAL PEMBERSIH DIRI (SELF CLEANING MATERIAL) Diana Vanda Wellia
Jurnal Riset Kimia Vol. 9 No. 2 (2016): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v9i2.286

Abstract

The photocatalytic properties of TiO2 compound in anatase phase can be activated under visible light by nitrogen modification and its ability can be increased by generated porous structure using polietilen glikol (PEG) on TiO2 thin film surface. The porous N/TiO2 thin films were prepared by heating aqueous peroxotitanate thin films by addition of polietilen glikol (PEG) deposited uniformly on superhydrophilic uncoated glass at 500 oC for 1 h. The result of X-ray diffraction (XRD) confirmed the resence of only anatase phase for all samples. The UV-Vis spectroscopy showed the synthesized porous N/TiO2 thin films exhibit the absorption in the visible range (400-500 nm). Photocatalytic activity of porous N/ TiO2 thin films were evaluated by using fourier transform-infrared spectroscopy (FTIR) to determine the ability of this photocatalyst for stearic acid degradation under visible light irradiation. The result showed that N/TiO2/PEG-2.1 thin film degraded the stearic acid was about 87,86%, which was 1,12 times higher than that of N-doped TiO2 and 9,9 times higher than that of undoped TiO2 thin film.
PENJERNIHAN AIR SUMUR MENUJU AIR LAYAK MINUM DENGAN METODA LAPISAN MULTI MEDIA ( LMM ) Neneng Swesty; Rahmiana Zein; Z. Zilfa
Jurnal Riset Kimia Vol. 10 No. 1 (2019): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i2.297

Abstract

The Multi Soil layering (MSL) system is a liquid waste treatment method with the use of soil as the main medium and the organic material formed in brick and arranged in layers with a homogeneous zeolite layer. The MSL system is made of acrylic (50 x 15 x 50) cm containing a brick (4 x 9 x 15) cm and (4 x 5 x 15) cm of volcanic soil mixture as the main medium mixed with charcoal, rice husk, and iron powder (70 : 10 : 10 : 5)%, permiable layer is used zeolite (2-3) mm. The sample came from the well water of one of villager at Jati, Padang. Efficiency of SML system for aeration process on turbidity parameter with flow rate variation of 2, 4, 6, 8 mL/min reach 99,8 %, for non aeration process efficiency of turbidity decrease 88,14 %. While for the flow rate of 10, 20, 40, 80 mL/min, the efficiency of decrease for aeration at parameters Mn 66,44 %, nitrite 59,74 %, nitrate 58,34 %, turbidity 54,63 %, while in non aeration efficiency decrease turbidity reach 44,04 %, Mn 47,26 %, nitrite 49,74 %, nitrate 45,57 %. Of all efficiency values decreasing all parameters already complied drinking water quality standard according to Permenkes RI No. 492/Menkes/Per/IV/2010.
Sintesis Senyawa Aurivillius Lapis Empat PbBi4Ti4O15 dan PbBi3NdTi4O15 dengan Metode Lelehan Campuran Garam NaCl-KCl dan Karakterisasi Struktur Gita Rachmad Wibowo; Emriadi Emriadi; Zulhadjri Zulhadjri
Jurnal Riset Kimia Vol. 10 No. 2 (2019): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v10i2.307

Abstract

Four-layered Aurivillius phases PbBi4Ti4O15doped with Nd3+ with formula PbBi3NdTi4O15 were synthesized by molten-salt technique using NaCl and KCl (1:1 molar ratio) as the flux. Precursors were weighed stoichiometrycally and grinded with salts mixture in 1:7 ratio (product : salts mixture) until homogenous. The samples were heated at temperature 600oC, 700oC, 800oC, and 900oC for 5 hours for each temperature. The products were characterized by X-ray diffractometer (XRD), Scanning Electron Microscope (SEM) and LCR-meter. XRD data were refined by Rietica program using Le Bail technique. Refinement results showed the best structure as the A21am of space group for both samples. Surface analysis for each samples morphology is the plate-like by SEM characterization. Dielectric constants measured at room temperature show that the sample doped Nd3+ has lower value than sample without containing Nd3+ cation.
STUDI OPTIMASI EKSTRAKSI KANDUNGAN SENYAWA FENOLIK TOTAL DAN UJI AKTIVITAS ANTIOKSIDAN DARI DAUN MANGGIS (Garcinia mangostana Linn.) Emil Salim; Yogi Afritunando; Nindi Antika Febriana; Mai Efdi
Jurnal Riset Kimia Vol. 10 No. 1 (2019): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i2.308

Abstract

This study aims to determine antioxidant activity and total phenolic content of mangosteen leaves in several different solvents. The antioxidant activity test of the extract was determined by the DPPH method and the total phenolic content was determined by the Folin-Ciocalteu method. The phytochemical test of mangosteen leaves showed the presence of phenolic compounds, saponins, triterpenoids and alkaloids. The extraction results increase with increasing water content in methanol, ethanol and acetone. The highest amount of extract was obtained using 50% acetone solvent (34.98 ± 0.17%). Extraction using 100% ethanol showed the highest total phenolic content (614.25 ± 5.58 mg GAE / g extract) and the lowest IC50 value (5.81 mg / L). The results of this study indicate that the use of 50% acetone solvent can optimize the amount of extract and 100% ethanol can optimize the content of total phenolic compounds and antioxidant activity of mangosteen leaves.

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