Jurnal Kimia Sains dan Aplikasi
ISSN / EISSN : 1410-8917 / 2597-9914
Current Publisher: Institute of Research and Community Services Diponegoro University (LPPM UNDIP) (10.14710)
Total articles ≅ 267
Latest articles in this journal
Published: 29 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 85-90; doi:10.14710/jksa.24.3.85-90
Coronavirus is a pandemic in the world. It requires researchers and scientists to work hard to find a vaccine or drug to inhibit the development of the coronavirus. Many drugs have been used, such as remdesivir, lopinavir, and chloroquine. However, how effective is the use of these drugs for inhibiting the coronavirus’s growth? There is no research has been done. Curcumin is now known as one of the compounds that have some biological activities, and it is also can potentially be used as a CoV-2 inhibitor. The computational study, i.e., molecular docking and molecular dynamic, can help researchers to predict which compounds have the potential as an inhibitor against the CoV-2 coronavirus. In this study, lopinavir was used as a positive control. Lopinavir and 45 curcumin analog compounds were docked against the main protease protein with 6LU7 PDB ID. Based on the docking results, it was discovered that compound 1, compound 2, and compound 4 have the same binding orientation as lopinavir. Molecular dynamic simulation with the lowest binding free energy conformation was used to check these compounds’ stability. Only compound 4 was maintained to observe hydrogen bonding with Lys5 and Lys137 with a distance of 2.9 Å. The distance of hydrogen bonds and binding free energy over simulation time is essential to elucidate the potential compound’s affinity. For then, compound 4 can be used as a potential inhibitor against the CoV-2 coronavirus.
Published: 28 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 91-100; doi:10.14710/jksa.24.3.91-100
Diclofenac sodium is a non-steroidal anti-inflammatory drug with a relatively short release time. This short release time promotes a more frequent drug consumption and could lead to side effects in the stomach, e.g., gastrointestinal disorders, gastrointestinal bleeding, and gastric ulcers. A drug delivery system with a slow-release activity is one of the promising technologies to control the drug amount released to the stomach. A surfactant-modified natural zeolite as a carrier for diclofenac sodium has been used in this study. This study focused on the preparation, characterization, and slow-release performance of HDTMA-modified natural zeolite as a carrier for diclofenac sodium. The zeolite underwent chemical and physical activation, as well as milling prior to use. It was proven that the zeolite used was dominated by mordenite and clinoptilolite with high stability properties towards acid treatments, as indicated by the XRD patterns. A modification of the zeolite surface using HDTMABr was also successfully performed, indicated by the appearance of peaks at wavenumbers of 2923.05 cm-1 and 2853.39 cm-1 (symmetrical and asymmetrical CH2 strains of HDTMA molecules, respectively) in the FTIR spectra. The synthesized HDTMA-modified natural zeolite also showed an excellent surface property such as surface area, pore-volume, and size, as indicated by the BET-BJH isotherms on the nitrogen adsorption. The slow-release performance of the zeolite-based drug delivery system was studied by investigating the adsorption-desorption behavior of HDTMA-modified zeolite towards diclofenac sodium. The HDTMA-modified zeolite adsorbed the diclofenac sodium of 54.01% at a pH of 7.5, the contact time of 60 min, and the initial concentration of 100 ppm. The adsorbed diclofenac sodium of 73.95% could be released from the HDTMA-modified adsorbent for 8 h, mimicking the time length of drug metabolism in the human body.
Published: 22 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 77-84; doi:10.14710/jksa.24.3.77-84
Li7La3Zr2O12 (LLZO) is a garnet-type electrolyte for all-solid-state lithium-ion batteries (ASSB). It has good chemical and electrochemical stability against lithium and a relatively high ionic conductivity. However, the ionic conductivity needs to be further increased to provide a high specific capacity of the ASSB. Element doping into LLZO is an effort to increase molecular defect, known to enhance the conductivity. This research studied the effect of the Na2B4O7 addition on the LLZO synthesis, producing LLZBO(A). The investigation aims to understand whether the sodium ions dope into the LLZO structure during synthesis, or it is only B ions to enter into the structure. Therefore, another synthesis with B2O3 of B precursor was conducted for comparison (LLZBO(B)). The precursors were mixed stoichiometrically by following the formula of Li7-xLa3-xZr2-xBxNaxO12 (LLZBO, x= 0.15; 0.20; 0.30). XRD analysis equipped with Le Bail refinement found that LLZBO(A) and LLZBO(B) mainly consist of cubic and tetragonal LLZO with a %mol of 69.06 – 69.84 %, and the main secondary phase is La2Zr2O7. The surface morphology of LLZBO(A) and LLZBO(B) is almost similar to the irregular form of large aggregates. The particles become more dispersed when 0.3 %mol dopant was submitted. Impedance analysis found a high ionic conductivity of LLZBAO(A)0.3 1.042x10-3 Scm-1.
Published: 22 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 101-107; doi:10.14710/jksa.24.3.101-107
Cholesterol plaque buildup in artery walls occurs due to oxidation of Low-Density Lipoprotein (LDL) molecules by free radicals, which are a risk factor for coronary heart disease. Piper crocatum contains active compounds that can act as HMG-CoA reductase inhibitors, such as flavonoids, alkaloids, polyphenols, tannins, and essential oils. This study aimed to predict the potential of Piper crocatum extract and fraction compounds as HMG-CoA reductase inhibitors by investigating the ligand affinity to the HMG-CoA reductase enzyme. Ligand and receptor preparation was conducted using BIOVIA Discovery Studio Visualizer v22.214.171.12450 and AutoDock Tools v.1.5.6. Molecular docking used AutoDock Vina, while ligand visualization and receptor binding used PyMOL(TM) 126.96.36.199.Edu. The receptor used was HMG-CoA reductase (PDB code: 1HWK) with atorvastatin as a control ligand. Catechin, schisandrin B, and CHEMBL216163 had the highest inhibition with affinity energies of -7.9 kcal/mol, -8.2 kcal/mol, -8.3 kcal/mol, respectively. Amino acid residues that played a role in ligand and receptor interactions were Ser684, Asp690, Lys691, Lys692.
Published: 12 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 70-76; doi:10.14710/jksa.24.3.70-76
The focus of this study was to compare the antimicrobial activity of silver nanoparticles (AgNPs) synthesized using ethanol extracts (AgNPE) and water extracts (AgNPA) from four o’clock flowers (Mirabilis jalapa) against Staphylococcus aureus. AgNPs were characterized by UV-Vis diffraction, FTIR, SEM, and X-rays. UV-Vis analysis showed that AgNPA has an SPR band of about 460 nm and 530 nm for AgNPE, which proves the characteristics of the absorbance area of AgNPs. SEM images of AgNPE and AgNPA show a cuboid shape with a mean diameter of 80 and 30 nm, respectively and well dispersed. The response to the presence of polysaccharide biomolecules involved in forming AgNPs was analyzed using a Fourier transform infrared spectrometer. The result was that AgNPA and AgNPE have different reducing agents. The plant extracts, AgNPE and AgNPA, were studied for their antimicrobial activity against Staphylococcus aureus. The result was that both AgNPA and AgNPE showed good activity and showed that AgNPA with less inhibition was more effective than AgNPE.
Published: 8 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 62-69; doi:10.14710/jksa.24.2.62-69
This research aims to make a polypyrrole (PPy) membrane and crude extract of polyphenol oxidase (PPO) as a membrane of mPPy/PPO apple extracts. The membrane of PPy/PPO-apple extract has been synthesized by the electrodeposition method. The electrolyte composition consists of a mixture of 0.10-0.20 M pyrrole (Py) and 50-100% PPO apple extract, which is stable using 50 mM of phosphate buffer solution at pH 6.80-7.00 and room temperature. The electrodeposition process is used 400 mesh steel gauze anode ST-304 and carbon plate cathode. Electrodeposition is carried out at potential = 5.00-6.00 V; current = 0.02-0.25 A; the distance from both electrodes = 1.00-2.00 cm for 300-500 seconds. The results from the deposition of PPy/PPO apple extract of the anode are a membrane of mPPy/PPO-apple extract, with total enzyme activity (U) = (957,1441, 2287 and 1754) using 2.00-5.00 mM phenol as a substrate which is measured based on the UV-visible spectrophotometric method. PPy and mPPy/PPO-apple extracts were characterized by SEM and SEM-EDS. The membrane of mPPy/PPO-apple extract can be used to remove phenol in industrial wastewater samples is 50-65% with a filtration capacity of 500 mL for 2 hours.
Published: 6 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 43-50; doi:10.14710/jksa.24.2.43-50
A screen-printed carbon electrode is a suitable electrode for electrochemical sensors due to its simplicity and portability. This study aimed to fabricate a screen-printed carbon electrode modified with poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (SPCE-PEDOT:PSS) to improve the electrochemical performance for uric acid detection. The SPCE was fabricated using a layer-by-layer painting process of conductive ink consisting of graphite as a conductive material, polystyrene as a polymeric binder, and dichloromethane solvent on a polyvinyl chloride paper substrate. The fabricated SPCE was then modified with PEDOT:PSS by a drop-casting method. The characterization of SPCE-PEDOT:PSS surface morphology was performed using the scanning electron microscopy technique. The SPCE-PEDOT:PSS provided an acceptable linearity (R2 = 0.9985, 0.9993, 0.9985), sensitivity (0.070, 0.015, 0.024 µA/µM), precision (%RSD = 2.70%, 2.89%, 2.40%), limit of detection (1.61 µM, 1.14 µM, 1.62 µM), and limit of quantitation (5.37 µM, 3.81 µM to 5.39 µM) in measurement of uric acid standard solution using cyclic voltammetry, amperometry, and differential pulse voltammetry techniques, respectively. The studies using SPCE-PEDOT:PSS indicated that the electrode could be applied in the electrochemical measurement of uric acid in the human urine sample.
Published: 6 March 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 37-42; doi:10.14710/jksa.24.2.37-42
Generally, biomass consists of various amounts of minerals. These minerals influence the biomass characteristics and behavior during their use in a thermochemical process such as pyrolysis. The conversion during pyrolysis and its final product will be affected. This research was carried out to study the impact of washing treatment in water and acid solutions on the rice husk as the raw material for pyrolysis. Also, the effect of acid strength (citric acid as the weak acid while nitric acid as the strong acid) and its concentration (1, 5, and 10 wt.%) was investigated. The results confirmed from the thermogravimetry (TGA/DTG) analysis, surface analysis (SEM), and spectra (FTIR) analysis describe the treatment using water caused less change on the rice husk surface structure and its thermal degradation. However, it seems hard to reduce the minerals (proved from XRF analysis). Meanwhile, the treatment using acids solution resulted in lower mineral composition than the rice husk without treatment. This result is more visible for demineralization using a 5 wt.% nitric acid solution. However, for a higher concentration (washing treatment using 10 wt.% solutions of nitric acid), the degradation on rice husk structure was more occurred.
Published: 24 February 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 51-57; doi:10.14710/jksa.24.2.51-57
Preparation and characterization of Fe3O4 magnetized natural zeolite adsorbent for adsorption of methylene blue dye have been carried out. Natural zeolite/Fe3O4 adsorbent preparation was carried out using coprecipitation of Fe2+ and Fe3+ ions (1: 2 mol ratio) on the natural zeolite surface. Characterization was carried out using X-Ray Diffraction (XRD), Fourier Transform Infra-Red (FTIR), and Scanning Electron Microscopy (SEM) to determine the effect of Fe3O4 on the natural zeolite surface. UV-Vis spectroscopy was used to determine the concentration of methylene blue after the adsorption process. The characterization results showed that Fe3O4 was successfully embedded in the natural zeolite without damaging the natural zeolite's crystallinity. Natural zeolite/Fe3O4 adsorbent showed easy separation from water medium after the adsorption process. The optimum conditions for adsorption were achieved at the contact time of 60 minutes, and the initial concentration of methylene blue was 30 ppm with an adsorbent mass of 25 mg. Adsorption kinetics followed pseudo-second-order reaction kinetics, and adsorption isotherm followed Langmuir isotherm with an adsorption capacity of 32.258 mg/g.
Published: 24 February 2021
Jurnal Kimia Sains dan Aplikasi, Volume 24, pp 15-21; doi:10.14710/jksa.24.1.15-21
The crude polar extract of mangosteen fruit pericarp not only has a moderate antioxidant activity of (55±4 μg/mL) but also has high cytotoxicity (16±0.5 μg/mL). The high cytotoxicity presumably is caused by the presence of complex cytotoxic compounds from the mangosteen pericarp. To obtain a non-toxic extract preparation with high antioxidant activity, polar crude 50% ethanol extracts of mangosteen pericarp were partially purified using reverse-phase column chromatography with Silica C18 as the stationary phase and acetonitrile-water gradient elution. Six of the ten fractions collected had high antioxidant activities, with IC50 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging antioxidant levels