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Assyifa Junitasari
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al Kimiya : Jurnal Ilmu Kimia dan Terapan
Published by Universitas Islam Negeri Sunan Gunung Djati Bandung
ISSN : 24071897     EISSN : 24071927     DOI : http://doi.org/10.15575/ak
Core Subject : Science, Engineering,
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry
The scope of al Kimiya Jurnal Ilmu Kimia dan Terapan s publication included general studies and special studies The general studies are pure chemistry in general and in specific fields as follows Study of inorganic organic and biochemical substances materials that have traditionally been successively entered into studies of inorganic chemistry organic chemistry and biochemistry. Some examples of specific topics from the study of these substances are bioanorganic bioorganic organometallic heterogeneous catalysts transition metal chemistry and coordination chemistry (complex) metabolism enzymology natural material chemistry and solids. Study of the physical and chemical properties of matter and their changes that have traditionally entered into the study of physical chemistry. Some examples of specific topics from this study are reaction kinetics and mechanisms surface chemistry polymers dyes, thermo dynamics chemistry theoretical chemistry and computation membrane catalysis radiochemistry electrochemistry photochemistry and spectroscopy. Experimental studies and chemical instrumentation that have traditionally entered into analytic chemistry studies. Some examples of specific topics from this study are spectroscopy microscopy and chromatography. Specific studies that can be raised in the publication of al-Kimiya in general are as follows Study of applied chemistry in the field of food. Some examples of specific topics from this study are proteins lipids carbohydrates vitamins minerals enzymes additives food coloring agents and food chemical technologies related to these topics. Study of applied chemistry in the energy field. Some examples of specific topics from this study are photochemistry cell chemistry fuel biomass petroleum and natural gas fuels renewable chemical energy sources and chemical energy conversion Study of applied chemistry in the field of environment. Some examples of specific topics from this study are soil chemistry aquatic chemistry atmospheric chemistry green chemistry toxicology and water treatment. Pure chemistry studies as well as applied in the problem of local wisdom. This study was inspired by the lack of habits traditions in local tribe customs or culture related to the use of substances from nature. Back to Nature can be the ultimate term to describe the contribution of culture to modern traditions that are more prudent in managing nature. Pure and applied chemistry studies to understand the universality values of Islam rahmatan lil alamin.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 10 Documents
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Search results for , issue "Vol. 12 No. 1 (2025): June 2025" : 10 Documents clear
Activity of Zn(II)-Curcumin Complex Compound as An Antibacterial Agent Against Staphylococcus Aureus and Escherichia Coli Silalahi, Imelda Hotmarisi; Sadenta, Deby Pascalia; Ardiningsih, Puji; Widiyantoro, Ari
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.39415

Abstract

Curcumin has very broad biological activities, but it has low stability. The stability of curcumin can be enhanced by forming complex compounds with metal ions, hoping to preserve its activity. This paper reports the antibacterial activity of zinc(II)-curcumin compared with curcumin alone. Zinc(II)-curcumin complexes have been prepared using ZnCl2 metal precursor in ethanol under reflux conditions with a curcumin:metal molar ratio of 2:1. The reaction, followed by thin-layer chromatography, showed that curcumin had reacted completely with zinc(II) metal ions after 4 hours reaction. The UV-vis spectra of the Zn(II)-Curcumin complex experienced a bathochromic peak shift of 5 nm. The FTIR spectra of the zinc(II)-curcumin complex indicated interactions between the ß-1,3 diketone groups of curcumin and Zn2+ metal ions, manifested by a decrease in absorption band intensity and shift in wave numbers of phenolic -OH and enolic C=O groups. Antibacterial activities of curcumin and zinc(II)-curcumin were evaluated using the disc diffusion method against E.coli and S.aureus bacteria. Curcumin and zinc(II)-curcumin exhibited a moderate antibacterial activity against the bacteria. Inhibition zone diameters against E.coli demonstrated by curcumin and zinc(II)-curcumin at a dose of 100 µg/disc are 6.05 mm  and 5.30 mm, respectively. Meanwhile, at the same dose, curcumin and zinc(II)-curcumin showed inhibition zone diameters against S. aureus in 5.39 mm and 6.09 mm, respectively. The observations demonstrate the preservation of curcumin antibacterial activities although it is introduced with zinc(II) ion.
Characteristics of Electric Current in The Electrolysis of Acid and Alkaline Water Production for Health Kurniawan, Ekki; Raharjo, Jangkung; Manfaati, Rintis; Yulinda, Yulinda
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.39460

Abstract

Acidic and alkaline water with potential health benefits can be produced through the process of electrolysis. In addition to the applied voltage, electric current is a crucial parameter in the electrolysis process. The energy consumed during electrolysis can be determined by measuring the voltage, electric current, and duration of operation. This study aims to investigate the characteristics of electric current during the electrolysis of mineral water to produce Electrolyzed Reduced Water (ERW) and Electrolyzed Oxidized Water (EOW), commonly referred to as alkaline and acidic water, respectively. The electrolysis current is monitored at specific time intervals (0, t₁, and t₂) throughout the process. In the initial stage (from 0 to t₁), the current increases exponentially, similar to the charging current behaviour of an inductor (L). In the second stage (from t₁ to t₂), the current decreases exponentially, resembling the discharge of a capacitor (C). In the final stage (after t₂), the current stabilizes and remains nearly constant, analogous to current flow through a resistor (R). A novel aspect of this study is the introduction of an equivalent RLC transient circuit model to describe the dynamic behaviour of electrolysis current. In this model, the electrolysis process is represented by a series RLC circuit with a switch operating sequentially at 0 (inductor charging), t₁ (capacitor discharging), and t₂ (resistive steady state). To the best of our knowledge, this RLC-based interpretation of electrolysis current behaviour in the context of ERW and EOW production has not been previously reported.
Biomass Contents Of Chlorella Pyrenoidosa Cultivated In Cobalt-Less Fertilizer-Enriched Saline Water Widyatama, Awang; Widyatama, Satria Aqilla; Fajry, Zaidan Al; Atmadi, Atmadi; Mulyawati, Ade Heri; Stiawan, Elva
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.39468

Abstract

This research aims to provide some information regarding the metabolite contents of the green microalgae Chlorella pyrenoidosa cultivated in designed saline water enriched with affordable commercial fertilizer products in Indonesia. Chlorella pyrenoidosa growth conditions and bioactive compounds were obtained through cultivation and extraction processes. The microalga growth in two different conditions   was analyzed based on growth curves between microalgae cultivated in a Guillard f/2 medium   and the Cobalt-less fertilizer-enriched saline water.   The biomass was profiled using UPLC-QToF-MS and DPPH assay. As a result, Chlorella pyrenoidosa cultures were normally grown on fertilizer-enriched saline water, but with a lower yield performance than those cultivated in the Guillard f/2 medium. The UPLC-QToF-MS result implies that several peptide and lipid derivatives were detected in the harvested microalgal biomass, with the peptide derivatives as the dominant compounds. The limited antioxidant performance was displayed by the untreated biomass extract. This finding implies that several optimizations are still required in the upstream and downstream stages in culturing Chlorella pyrenoidosa by using an uncommon growth medium.
Adsorptive Performance of Gelatin-Hematite Composite Synthesized from Iron Lathe Waste Using Guava Leaf Extract for Pb(II) Removal from Aqueous Solutions Khoiroh, Lilik Miftahul; Barroroh, Himmatul; Taufik, Moh; Royyanuddin, Moh; Al Akbar, Ramadhana Fatahillah; Amaliyah, Nada Rifqi; Yulianti, Eny
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.40817

Abstract

Hematite was successfully synthesized from iron lathe waste using guava leaf extract as a reducing agent. To enhance adsorption capacity, hematite was composited with gelatin, a polymer containing amide and carboxylate functional groups. The hematite-gelatin composite was employed as an adsorbent for Pb solutions. This study investigated the material's structure and the adsorbent's performance, including the composite's optimum dosage and contact time. Characterization techniques included XRD, FTIR, SEM-EDX, and AAS analyses. XRD analysis revealed that the hematite-gelatin composite exhibited a high degree of crystallinity. FTIR analysis of the guava leaf extract spectrum identified phenolic vibrational absorption with strong intensity at 3447 cm-1 (O-H stretching) and a weak C-H vibrational bond at 2928 cm-1. An ester group (C=O) at 1726 cm-1 indicated the presence of tannin compounds. For the hematite-gelatin composite, a C-O absorption band was observed at 1075 cm-1, along with Fe-O absorption bands at 430 and 519 cm-1. The SEM results show that the gelatin-hematite composite has a hollow and layered surface. The EDX analysis results show that the material contains C, N, O, Pb, and Fe, which indicates that gelatin has interacted with Pb when it becomes a composite and has absorbed Pb at a level of 1.4% after adsorption. Performance evaluation of the hematite-gelatin composite demonstrated high adsorption efficiency for Pb solutions. The adsorbent exhibited a high adsorption capacity of 800 mg/g with an optimal adsorbent dosage of 15 ppm and an optimal contact time of 70 minutes. The adsorption kinetics of the hematite-gelatin composite followed a pseudo-first-order adsorption model.
Solvent-Free Synthesis of Dihydropyrimidinone by Using Molecular Iodine as Catalyst Fadlan, Arif; Pratama, Landaeta Yolga; Ilfahmi, Yan Alamanda
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.42254

Abstract

Dihydropyrimidinone with diverse pharmacological activities can be obtained through the multicomponent of Biginelli reactions by heating aldehyde, ethyl acetoacetate and urea/thiourea in ethanol with the addition of hydrochloric acid. However, this reaction is toxic and shows several drawbacks. Further development for Biginelli reaction was conducted by using heterogeneous catalyst, green solvents, and sustainable heating such as microwave or ultrasound. But various obstacles are also found from these strategies. There are still chances to study the Biginelli reaction by using relatively simpler methods and the readily available and environmentally friendly chemicals. Iodine is a mild Lewis acid, easily available at an affordable price, non-toxic, and environmentally friendly. Iodine has been used in various reactions and organic transformations with high efficiency and selectivity. This report aims to study the solventless synthesis of ethyl 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate 4 by using molecular iodine. The reaction was studied by mixing benzaldehyde 1 as aromatic aldehyde, urea 2, and β-keto ester in the form of ethyl acetoacetate 3 with and without the addition of ethanol as solvent. The compound 4 (45% yield) was yielded from a solvent-free reaction whereas the use of ethanol gave the product 4 in 50%yield. The IR, NMR spectra, and HRMS analysis were used for the establishment of the structure of product 4. These finding give new perspective in the preparation of dihydropyrimidinone(s).
Synthesis of Bi4Ti3O12/Alga for Ciprofloxacin Degradation Prasetyo, Anton; Adi, Tri Kustono; Kartika, Siska Ela; Faturrohmi, Fauziah; Khanif, Juwita
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.42256

Abstract

Antibiotic waste has become a serious issue for ecosystems, and one method that offers great potential to address this problem is photocatalysis. To enhance the photocatalytic activity, one approach is to impregnate the photocatalytic compound onto a supporting material and become composite material. In this study, Bi4Ti3O12/Algae (Spinossum cottonii, Euchema spinossum, and Sargassum sp) composite compounds were synthesized with various algae, including Sargassum and Spinosa. The diffractogram and IR spectra data indicate that the composite compounds were successfully synthesized. The photocatalytic activity test results demonstrate good potential for the Bi4Ti3O12/Euchema spinossum composite in the degradation of ciprofloxacin, as it was able to degrade 30% of ciprofloxacin within 60 minutes.
Effect of Copper-Based Fungicide on Chemical Composition of Cocoa Seeds Lawal, Amudalat Ranti; Olayinka, Bolaji Umar; Olahan, Ganiyu S.; Omorinoye, Omolayo A.; Abdulsalam, Halimat A.; Abdulra'uf, Lukman Bola
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.43696

Abstract

Production of cocoa seeds, one of Nigeria’s major non-oil foreign exchange earners as well as a major raw material for the beverage industry, is greatly hindered by diseases caused by various species of the genus Phytophthora. To avert this, copper-based fungicides are sprayed on the leaves of cocoa trees to control or prevent the survival of this organism by the farmers without paying attention to the effects of this chemical on the proximate composition of cocoa seeds. This study therefore investigated the effects of a copper-based fungicide (Ridomil Gold Copper) on the quality of the cocoa seeds by spraying cocoa trees, including the pods, with 50.00 g/L of copper-based fungicide. The results obtained showed that cocoa seeds from the control trees showed significantly higher contents of fiber (4.51%), protein (15.1%), and fat (36.1%) when compared to the respective values of 3.45, 3.95, and 7.59% obtained for the cocoa seeds harvested from the fungicide-treated cocoa trees. All other proximate compositions did not show any statistical difference, except for carbohydrate and calorific values, which were significantly higher in cocoa seeds from fungicide-treated cocoa trees. Seeds from fungicide-treated trees showed significantly higher potassium, phosphorus, and magnesium contents but lower zinc and copper contents. However, phytochemicals such as phenols, alkaloids, flavonoids, and tannins were significantly lower in content in the seeds of fungicide-treated cocoa trees. The contents of glycosides and antioxidants in the cocoa seeds were statistically similar for both the control and treatment, except for ascorbic acid, which showed a significantly lower value (4.8 mg/100 ml) in cocoa seeds from fungicide-treated cocoa trees, compared with the value recorded for the control in this study (13.33%). The foregoing results showed that the use of copper-based fungicides for the control of black pod disease in cocoa adversely affected the quality of cocoa seeds from the treated trees.
Synthesis of Complex Compounds of Cr(III) Metal Ions and Their Application as Fluorosensors of Pb(II) and Cu(II) in Laboratory Waste Syahputri, Yulian; Sutanto, Sutanto; Kusumawardani, Linda Jati; Saputra, Muhammad Rizki
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.43967

Abstract

Indonesia's exposure of lead (Pb) and copper (Cu) heavy metal ions to humans and the environment has received increased attention over the past few decades as a result of the increasing application of heavy metals in various industries and transportation. Complex compounds of Cr3+ sensors with fluorescence-based pyrazoline-derived ligands (fluorosensors) have the potential to detect Pb2+ and Cu2+ heavy metal ions. The purpose of this study is to synthesize complex compounds of Cr3+ ions with pyrazoline-derived ligands and its potential as a fluorescence-based sensor of Pb2+ and Cu2+ heavy metal ions. Complex compounds formed are characterized and fluorosensor study by spectroscopic methods. The results showed that the synthesis of complex compounds was successfully carried out and a brown precipitate with a melting point of 253.2°C was obtained. Based on the results of the characterization of complex compounds of Cr3+ metal ions with pyrazolin-derived ligands using a UV-Vis spectrophotometer, two absorption peaks were obtained at 226 and 370 nm, two peaks indicating the presence of transition types π→π* and n→π*. The fluorescence spectrophotometer results showed two emission peaks, the peak absorption maximum of Cr3+ complex compounds was in the region 491 nm with a fluorescence intensity of 320.40 a.u. The determination of the fluorosensor potential of Cr3+ complex compounds with the addition of Pb2+ and Cu2+ metal ions showed significant changes in fluorescence so that fluorosensor types were obtained for Cr3+ metal ion complex compounds with Pb2+ and Cu2+, namely "turn-on" and "turn-off", respectively.
Effect of Molecular Weight of Chitosan in The Coating Solutions on The Shelf Life of Tuna Fish Fillets Indarti, Dwi; Khofifah, Marhamatul; Piluharto, Bambang; Ananda, Tinok Dwi
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.44715

Abstract

Tuna, a valuable Indonesian marine commodity, is known for its highly valued dietary and nutritional sources. However, this red meat fish is particularly prone to deterioration and spoilage due to its inherent properties. Liquid smoking, a popular fish preservation method in Indonesia, has garnered significant consumer interest but remains insufficient to prevent fish decay entirely. Therefore, this study aimed to enhance tuna fish fillet (TFF) shelf life by developing a novel coating solution. This solution contains liquid smoke seasoning and chitosan with varying molecular weights (MW), as this property affects chitosan’s chemical, physical, and biological characteristics. In this research, fresh tuna were divided into four groups: a control group with no coating, a group with liquid smoke coating only (LS), a group coated using chitosan solution (Ch) with variations of MW (Low: 50-190 kDa, Medium: 190-310 kDa, and High: 210-375 kDa), and a group coated using liquid smoke seasoning with the same chitosan MW variation (Ch + LS). During 15 days of storage in the freezer, their chemical properties (pH, and Total Volatile Base Nitrogen - TVB-N) were analyzed. The finding showed that combining high MW of chitosan and liquid smoke as a coating solution improved TFF appearance, maintaining a desirable uniformly cherry red color. Moreover, this treatment showed a slower increase in pH (5.5 – 5.7) and TVB-N level (22 – 28 mg TVB-N/100 gram), indicating deterioration and spoilage delay during 15 days of storage compared to other treatments. This study underscores the efficacy of a preservation strategy in inhibiting deterioration and spoilage in tuna fish fillets during storage, thereby enhancing product quality and ensuring consumer safety.
Silver Leaching from Printed Circuit Board Using Deep Eutectic Solvent-Oxaline, Maline, and Succiline Fatimah, Soja Siti; Mora, Abraham; Sumarna, Omay; Ramdaniah, Hudaifatul A. N
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol. 12 No. 1 (2025): June 2025
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v12i1.46024

Abstract

The exponential growth in printed circuit boards (PCBs) waste, presents an urgent environmental and economic challenge. PCBs contain silver which has a high potential economic value. The high production of waste and the potential economic value make it important to recycle PCB waste. Recycling can be conducted by leaching silver using Deep Eutectic Solvent (DES). DES is environmentally friendly and able to form complexes with various types of metals. This research aims to study the effect of the HBD carbon chain length of oxalic acid, malonic acid, and succinic acid from choline chloride-based eutectic solvents (DES) on the efficiency of leaching silver from Printed Circuit Board (PCB) waste. Optimization of the solid/liquid ratio, time, and temperature is carried out to obtain optimum leaching conditions. The synthesis results show that DES oxaline 2:1, malin 1:1, and succilin 2:1 have good stability, forming a colorless, clear, and viscous solution. FTIR analysis shows a shift in the wave number of the -OH group due to hydrogen bond interactions between HBA and HBD molecules in the formation of DES. The leaching yield of DES against standard silver oxide was measured using AAS. DES oxaline 2:1 has the greatest efficiency compared to other DES variations. The results of optimizing standard silver leaching with DES oxaline showed that the S/L ratio was 40 mg/mL, with a time of 18 hours, at a temperature of 60°C which resulted in a recovery percentage of 90.90%, while for the PCB waste sample yielded an efficiency of 99.38%. The eutectic solvent oxaline has the potential to be an environmentally friendly solvent that is efficient in leaching silver from PCB electronic waste.

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