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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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Potensi Antimikroba dan Toksisitas Minyak Atsiri yang Diisolasi dari Biji Jintan (Carum carvi L.) Suryati Suryati; Emil Salim; Gustia Elizar
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.551

Abstract

Caraway (Carum carvi L.) is one of the oldest medicinal plants found in various countries such as West Asia, North Africa, Pakistan, India, North America, Northern Europe, Iran, Russia, and Indonesia. This plant has been use for traditional medicines to treat digestive disorders, flatulence, colic in infants, headaches, coughs, hypertension, eczema, pneumonia, diabetes, scabies, mouthwash and as an antiseptic. This plant is reported to contain around 1-9% essential oil in the seeds with various components and potential as bioactive compounds. In this study, essential oils were isolated from caraway seeds and determined their chemical content as well as their antimicrobial and toxicity. Isolation of essential oils was carried out by hydrodistillation and analysis of the chemical components of the isolated essential oils was carried out using the Gas Chromatography-Mass Spectrometry (GC-MS) method. The results of the GC-MS analysis showed the presence of 35 compounds with four main compounds, namely carvone (62.54%), limonene (23.39%), and trans-dihydrocarvone (8.20%). The antimicrobial activity test was carried out using the disc diffusion method, which showed strong activity against Staphylococcus aureus at a concentration of ≥75%, and against the fungus Candida albicans. The results of the toxicity test using the Brine Shrimp Lethality Test (BSLT) method showed that caraway seed essential oil was low toxic against Artemia salina Leach shrimp larvae with an LC50 value 568.3292 mg/L.
Sintesis, Karakterisasi Struktur, dan Kajian Molecular Docking Senyawa Turunan 4’-Metoksi Flavonol sebagai Antagonis Reseptor Estrogen Alpha (ER-a) pada Kanker Payudara Ihsan Ikhtiarudin; Rahma Dona; Neni Frimayanti; Rahayu Utami; Nurul Susianti; Abdi Wira Septama
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.553

Abstract

A long period of drug administration in breast cancer chemotherapy can cause various side effects. These situations encourage researchers to search for and develop alternative anticancer drugs through various approaches. This study aimed to synthesize a flavonol derivative (TF4) and to study the interactions of the synthesized compound with ER-α as one of the targeted receptors in breast cancer treatment. The synthesis was carried out using the stirring method and the study of interactions of TF4 with ER-α was performed through molecular docking against ER-α crystal structures bound to an antagonist (PDB ID: 3ERT) and agonist (PDB ID: 1A52). The synthesis of TF4 produced crude product in 58 % yield and pure product in 6 % yield. The structure of TF4 was confirmed by spectroscopic analyses including UV, FT-IR, 1D, and 2D NMR. The docking results showed that the TF4 does not form any conventional hydrogen bond with ER-α. However, it can form carbon-hydrogen (C--H) bonds and van der Walls interactions with several important residues on the active site of ER-α. In addition, the binding free energy values of TF4 (-9.14 and -9.50 kcal/mol) are more negative than estradiol (E2) as one of the natural ligands for ER-α. Thus, it can be estimated that TF4 can be bounded easier on the active site of ER-α than its natural ligand. It may presume that it can act as an estrogen antagonist because of the similarity in interactions and binding poses compared to TAM, TOR, dan 4-OHT as reference drug molecules.
Sintesis Cepat Nanopartikel Perak dengan Irradiasi Gelombang Mikro dan Aplikasinya sebagai Antibakteri pada Kain Katun Mohammad Alauhdin; Ahmad Dzulfiqar; Arsenius Olfa Herlistyawan
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.555

Abstract

Silver nanoparticles (AgNPs) are silver metal particles with nanoscale size. In the scale, they generate different properties compared to the original particle or material. AgNPs can be synthesized in several ways, one of which is through chemical reduction. This method is accelerated by heating, usually using conventional heating. However, the heating takes time, so it is less effective for application. In this study, AgNPs were synthesized by chemical reduction with sodium citrate as a reducing agent accompanied by microwave irradiation to speed up the synthesis process. The resulting AgNPs were then applied to cotton fabric as an antibacterial agent. The reaction lasted for 6 minutes, much faster than using conventional heating. The synthesized particles have an average size of 56.2 nm and are stable for up to 41 days of storage. The AgNPs then can be applied to cotton fabric and inhibit the growth of S. aureus and P. aeruginosa bacteria with a Minimum Inhibitory Concentration of 70%.
Ekspansi Termal, Oxygen Content, dan Sifat Elektrokimia Oksida SmBa0.5Sr0.5Co2O5+δ (70%) + SDC (30%) Sebagai Katoda SOFC Adi Subardi; Yen-Pei Fu
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.557

Abstract

The thermal properties of the double perovskite SmBa0.5Sr0.5Co2O5+δ (70%) + SDC (30%) have been investigated as potential cathodes for intermediate-temperature solid oxide fuel cells (IT-SOFC). This study also includes the oxygen content and electrochemical performance of long-term tests carried out to evaluate the electrochemical stability. Cathode powder is fabricated by a simple and relatively inexpensive solid-state reaction. Oxygen content decreased gradually from room temperature to 800oC by 18.3%. Doping 30% SDC into SBSC oxide can reduce the thermal expansion coefficients (TEC) value from 19.80 x 10-6 (K-1) to 18.17 x 10-6 (K-1) or a decrease of 8.23%. The activation energy (Ea) identified by the electrochemical impedance spectroscopy (EIS), low field (LF), and high field (HF) techniques were 125.3 kJ mol-1, 60.6 kJ mol-1, and 62.5 kJ mol-1, respectively. The SBSC73|SDC|SBSC73 symmetric cell test for 96 hours at 600oC showed an increase in the average polarization resistance value of 0.30% h-1. The cathode grains are evenly distributed with a size of 2-3 µm and tend to be porous. These results exhibit that SmBa0.5Sr0.5Co2O5+δ (70%) + SDC (30%) is a promising cathode material for IT-SOFCs.
Decreasing of Mangan (II) in The Water Using Membrane of Moringa Seed Powder-TiO2 with Variation of Mass TiO2 Ana Hidayati Mukaromah; Fandhi Adi Wardoyo; Ayu Rahmawati Sulistyaningtyas; Haikal Naufal Ghazi
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.512

Abstract

Mn (II) is a metal ion commonly used in steel alloys, pigment industries, welding, fertilizers, pesticides, ceramics, and electronics. According to the Regulation of the Minister of Health No. 32 of 2017, the permissible content of Manganese in dug well water is 0.5 mg/L. The purpose of this study was to determine the concentration of Mn (II) ions in water before and after passing through a Moringa Seeds Powder (MSP)-TiO2 membrane 20:1; 20:3; 20:5; 20:7; 20:9 and measure the percentage decrease in the concentration of Mn (II) ions in water after through the MSP-TiO2 membrane. The object of this research is a 55 ppm Mn (II) ion artificial sample at a flow rate of 0.56 mL/minute for 90 minutes with 90-watt radiation UV. The concentration of Mn (II) ion was measured by visible spectrophotometric method, the morphology of MSP, TiO2, and MSP-TiO2 membranes was characterized by SEM-EDX, and its diffraction spectra by X-Ray diffraction. The results obtained that the initial Mn(II) was 55.06 ± 0.031 ppm, the concentration of Mn (II) ions with the MSP-TiO2 membrane of mass MSP-TiO2 were 20:1; 20:3; 20:5; 20:7; 20:9 respectively 36.47±0.00; 44.16±1.15; 44.31±1.04; 44.94±0.94; 42.27±2.61 ppm. The percentage of decrease concentration of Mn (II) ion are 34.19±0.44%; 21.37±0.43%; 20.94±0.85%; 19.24±0.86%; and 19.66±0.86%. The highest percentage decrease in Mn (II) ion concentration was 34.15±0.44% in the variation of mass MSP-TiO2 20:1. This study concludes that the MSP-TiO2 membrane has the potential to reduce the concentration of Mn (II) ions in water.
Kajian Penggunaan Carbon Black N990 sebagai Bahan Pengisi Kompon Karet Alam: Sifat Dinamik, Kestabilan Termal, dan Ketahanan Panas Adi Cifriadi; Purwantiningsih Sugita; Tetty Kemala; Siti Nikmatin
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.560

Abstract

The manufacture of vibration damping material from natural rubber (NR) required an increase in dynamic properties, thermal stability, and resistance to heat. Using the Carbon Black N990 as a filler in NR vulcanizates can potentially increase on these properties. This research aims to study the effect of using Carbon Black N990 on dynamic properties, thermal stability, and aging resistance to heat in NR vulcanizates. The dynamic properties of NR vulcanizates were determined by Rubber Process Analyzer (RPA), while the thermal stability properties were studied by TGA, and heat resistance was determined by the thermal aging test. The RPA test results showed that adding 50 phr Carbon Black N990 in the NR compound could increase the value of the complex shear modulus to 65%. Furthermore, the results of the TGA test showed that the thermal stability properties of unfilled NR vulcanizates were better than that of NR vulcanizates containing Carbon Black N990. Unfilled NR vulcanizates were heat stable up to 353oC, while NR vulcanizates containing 15, 30, and 50 parts per hundred rubber (phr) Carbon Black N990, respectively, were heat stable up to 348.1oC, 348oC, and 349oC. Based on the requirements of ISO 4632-1, it showed that the NR compound containing Carbon Black N990 has good heat resistance properties. The NR compound formula contains 30 phr Carbon Black N990 showing good dynamic properties and heat resistance in accordance with EN 15129 requirements so that it has the potential to be used as a vibration damping material for earthquake-resistant structures.
Antibacterial Edible Coating from Mandarin Orange Peel (Citrus reticulata) and Moringa Leaf (Moringa oleifera) Extract for Fish Preservation Maulidan Firdaus; Desy Nila Rahmana; Diah Fitri Carolina; Nisrina Rahma Firdausi; Zulfaa Afiifah; Berlian Ayu Rismawati Sugiarto
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.563

Abstract

Approximately 10% of total fish production is wasted due to decomposition. Excessive formalin use in fish preservation can be potentially lethal. One of the natural preservatives is edible coating, which can be prepared from natural ingredients such as mandarin orange peel (Citrus reticulata) pectin and Moringa leaves (Moringa oleifera) which contain antibacterial compounds. The purpose of this research was to examine the antibacterial influence of edible coatings made from pectin of mandarin orange peel with the addition of Moringa leaf extract and to determine its effect on the freshness of nile tilapia (Oreochromis niloticus). Moringa leaf extraction was performed using the Soxhlet extraction method with 96% ethanol at 60–80 °C, while the mandarin orange peel was isolated by reflux using 1% HCl with a pH of 1.5 for 4 hours at 90 °C. Edible coating was synthesized from mandarin orange peel pectin and carboxymethyl cellulose (CMC) which was homogenized with distilled water, and glycerol was added as a plasticizer. Edible coatings were prepared with various concentrations of 0%, 50%, and 100% Moringa leaf extract. Nile tilapia with the addition of edible coatings experienced slower decay, especially in the variations of 100% Moringa leaf extract. This was evidenced by the quantitative test through the Total Plate Count (TPC) test which still did not exceed the limit of >5.6 log CFU/g.
Identification of Secondary Metabolites and FT-IR Analysis of Getih-Getihan Fruit Extract (Rivina humilis L.) Mariyam; Yulistia Anggraini; Tati Suhartati
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.565

Abstract

Getih-getihan (Rivina humilis L.) plants can be used as antibacterial, antioxidant and natural pesticides. Most of the biological activities of natural products originated from secondary metabolites contained therein. Studies have shown the effects of leaves, branches, and fruits extract of R. humilis towards biological activities. However, identifying the phytochemical compounds of R. humilis L. fruit is less discussed. Here we proposed research on the identification of secondary metabolite compounds of R. humilis L. fruit extract using phytochemical screening tests and spectroscopic method. The extraction of R. humilis L. fruit was proceeded by maceration method using methanol solvent. The series of phytochemical screening tests signified the presence of alkaloids, terpenoids, tannins and flavonoids. Furthermore, we applied FT-IR analysis to confirm the existence of functional groups in the secondary metabolite compounds. A broad absorption band showed the hydroxyl groups (O-H) at 3265 cm-1. The sharp band at 1632 cm-1 exhibited the C=C stretching band. The presence of C-N (stretching) was signified by the absorption band at 1237 cm-1, while the C-H bond in CH3 terminals (alkanes, alkyl group) was exhibited at 1401 cm-1. All the functional groups confirmed in the FT-IR analysis corroborated the phytochemical test results.
Sintesis dan Uji Fotostabilitas Kompleks Zn(II)-Astaxanthin Winda Rahmalia; Dwi Imam Prayitno; Adhitiyawarman; Septiani
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.568

Abstract

Astaxanthin is a pigment from the carotenoid group found in algae, shrimp, and crabs. Due to its chemical structure, astaxanthin has many health benefits but low stability against direct exposure to light and oxygen. In this study, the Zn-astaxanthin complex was synthesized using a reflux reactor at 37o and 60oC. Complex compounds were analyzed using a UV-Vis spectrophotometer and FTIR. The UV-Vis spectrophotometer analysis showed a bathochromic shift in acetone (475 to 477 nm). In comparison, in dimethyl sulfoxide, a hypsochromic shift (493 to 475 nm) was observed, and a new absorption peak was observed at 330 nm. FTIR analysis shows a decrease in the intensity of the C=O stretching vibration and -OH group vibration at 1712 and 1219 cm-1, respectively. This indicated an interaction between the metal ion Zn2+ and astaxanthin. Zn-astaxanthin has better stability than astaxanthin during irradiation, using a halogen lamp at a light intensity of 300 W/m2 for 6 hours. Based on the zero-order degradation kinetics model, the degradation rate constant of the Zn-astaxanthin complex was 0.0621, smaller than that of astaxanthin (0.0880).
Optimasi Proses Hidrolisis Rumput Laut Ulva Reticulata dengan Pelarut HNO3 untuk Produksi Bioetanol Sefrinus Maria Dolfi Kolo; Noviana Mery Obenu; Lusitania Kefi; Felicitas F.Fuel
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.574

Abstract

One alternative to make biofuels and replace petroleum-based fuels is to convert non-food ingredients from Ulva reticulata seaweed into bioethanol. Seventy percent of the earth's surface is covered by microalgae and seaweeds that can be converted into bioethanol. Ulva seaweed contains 50.3% carbohydrates in the form of heteropolysaccharides  such as glucose, arabinose, rhamnose and xylose. Optimization of the seaweed hydrolysis catalyzed by HNO3 using Microwave irradiation was done by varying acid concentration (1, 3, 5, 7%), hydrolysis time (30, 40, 50, and 60 minutes), and hydrolysis temperature (75, 100, 125, 150°C). Fermentation was carried out by varying inoculum concentrations (6, 8, and 10% (v/v)) for 5, 6 and 7 days at a temperature of 30°C and a pH of 4.5. Analysis of the surface texture of the sample was carried out by Scanning Electron Microscopy (SEM). The analysis of reducing sugars concentration was carried out using the dinitrosalicylate (DNS) method. Ethanol analysis was carried out by Gas Chromatography (GC). The results of SEM analysis showed that prior to hydrolysis, the surface morphology of the powder was still compact and intact. Whereas after being hydrolyzed with HNO3 it was seen that the surface texture of the powder suffered significant damage. The hydrolysis results showed that the optimum conditions during the pretreatment of U. reticulata powder was at acid concentration of 7%, reaction time of 50 minutes, reaction temperature of 150°C and 250 watts of power which gave hydrolysate with reducing sugar concentration of 86.5 g/L. Fermentation of the hydrolysate using yeast Saccharomyces cerevisiae produced bioethanol with concentration of 37.2% as analyzed using a gas chromatograph.

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