Indonesian Journal of Chemical Science and Technology (IJCST)
Indonesian Journal of Chemical Science and Technology (IJCST) is published by The Chemistry Department of Mathematics and Natural Sciences Faculty, Universitas Negeri Medan (UNIMED) Indonesia. This scientific periodical specializes in the study of the Multidisciplinary Chemistry Field, including Pure Chemistry and Applied Chemistry. The journal publishes original research and review which submissions on original advances in the understanding of Chemical application and Engineering areas, are welcome. Indonesian Journal of Chemical Science and Technology (IJCST) has been accredited for 4th grade (SINTA 4) by the Ministry of Research, Technology, and Higher Education of the Republic of Indonesia since Vol. 6, No. 1, 2023 according to the decree No.152/E/KPT/2023. The following are the field within the scope of Indonesian Journal of Chemical Science and Technology : Basic Chemistry Analytical Chemistry Physical Chemistry Organic Chemistry Inorganic Chemistry Biochemistry Applied Chemistry Chemical Engineering Indonesian Journal of Chemical Science and Technology has become a CrossRef Member and all articles published by Indonesian Journal of Chemical Science and Technology will have unique DOI number. About Indonesian Journal of Chemical Science and Technology Country of Publication: Indonesia Publisher: Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Negeri Medan. Format: Print & Online ISSN: p-ISSN: 2622-1349, e-ISSN: 2622-4968 Frequency: Biannual Publication Dates: January and July Article Processing Charges: Yes Types of Journal: Academic/Scholarly Journals Open Access: Yes Indexed & Abstracted: Yes Policy: Peer-reviewed Review Time: Eight Weeks Approximately IJCST is Indexes/Abstracted in: Google Scholar Garda Rujukan Digital (GARUDA) PKP Index International Standard Serial Number (ROAD) Neliti BASE
From Biowaste to Buffering Agent: Chicken Eggshell Filtrate in Controlling pH and Acid–Base Equilibrium Based on Eggshell Thickness
In weak acid tissue culture system, chicken eggshell biowaste containing 95% CaCO₃ could serve as an economical and green buffering agent. This study investigates the influence of eggshell filtrate thickness (1 cm, 2 cm and 3 cm) on pH improvement and acid–base balance in acetic acid (vinegar) and citric acid (lime juice) solutions. The filtrate media were prepared by cleaning, drying and crushing eggshells which organize the egg shell in columns with different thickness. Then, each acid solution was applied to the filtrate, using a range of pH values recorded before and after treatment. Filtrate with greater thickness consistently yielded a higher pH, regardless of the samples, and the 3 cm medium produced the highest rise in both samples. This is due to the higher interaction between acid solutions and CaCO₃, which allows for neutralization and shifting the chemical equilibrium toward less acidic conditions. The findings confirm that eggshell thickness significantly affects buffering efficiency. Therefore, eggshell-derived filtrate can serve as a sustainable and effective material for pH control in weak acid systems.
Analysis of Collision Theory in the Production of Candlenut Oil Biodiesel Using a Zeolite-KOH Catalyst
The methanol-to-oil ratio is one of the most important factors affecting biodiesel production through transesterification. This study investigated the effect of different methanol-to-oil ratios (1:2, 1:4, 1:6, 1:8, and 1:10) on biodiesel production from candlenut oil (Aleurites moluccanus L.) using KOH-activated zeolite catalyst from a collision theory perspective. Biodiesel was produced through transesterification at 60–65 °C with a stirring speed of 300 rpm for 1 h. The resulting biodiesel was characterized based on yield, volume, and density. The results showed that increasing the methanol-to-oil ratio up to 1:6 increased biodiesel yield and improved product quality. The highest yield of 95.47% was obtained at a ratio of 1:6 with a density of 0.850 g/mL. Further increases in methanol concentration reduced biodiesel yield. Based on collision theory, the 1:6 ratio provided the optimum condition for effective molecular collisions during transesterification.
In Silico Evaluation of Nitrogen-Containing Tetrahydropyridine and Piperidine Metabolites Identified from Strobilanthes tonkinensis Lindau Leaves as Potential Antibacterial Agents
Strobilanthes tonkinensis Lindau (daun paris), a Southeast Asian aromatic herb, contains several nitrogen-containing piperidine and tetrahydropyridine (THP) metabolites identified by prior GC-MS profiling but not previously evaluated in silico. This study assessed the molecular docking interactions of four such metabolites, 2-propionyl-3,4,5,6-tetrahydropyridine (2-PTHP), 2-acetyl-3,4,5,6-tetrahydropyridine (2-ATHP), 2-(2-furyl)piperidine (2-FP), and 1-(piperidin-2-yl)propan-1-one (PPO) against two bacterial protein targets, FtsA (PDB: 3WT0) and DNA gyrase subunit B (GyrB; PDB: 6KZV), using AutoDock Vina, complemented by ADMET prediction via SwissADME and ProTox 3.0. All four compounds showed moderate binding affinities against FtsA (−5.7 to −5.9 kcal/mol) and GyrB (−5.2 to −6.0 kcal/mol), substantially weaker than the native co-crystallized ligands (−11.5 and −8.9 kcal/mol, respectively). 2-FP exhibited the strongest GyrB affinity (−6.0 kcal/mol) and partially reproduced the native ligand's catalytic-residue contacts (ASP73, ASN46), whereas PPO showed the most catalytically relevant FtsA interaction profile, engaging SER13, VAL211, and ASP210. Structure-activity comparison identified the presence of a piperidine NH (hydrogen bond donor) versus an imine nitrogen as the principal determinant of polar-contact capacity within this scaffold. All compounds fully satisfied Lipinski's Rule of Five, showed high predicted gastrointestinal absorption and blood-brain barrier permeability, and were classified as GHS Acute Oral Toxicity Class IV with inactive predicted hepatotoxicity and carcinogenicity. These findings constitute preliminary computational evidence supporting 2-FP and PPO as candidates for further in vitro antibacterial validation..
Determination of Lead (Pb) Content in Commercial Fruit Juice Drinks Using Atomic Absorption Spectroscopy with Standard Addition Method
Lead (Pb) is one of the most hazardous heavy metals that may contaminate fruit juice through environmental pollution, raw materials, processing, and packaging. Continuous exposure to Pb poses significant health risks due to its cumulative toxicity. This study aimed to determine the Pb concentration in commercially packaged fruit juice using Atomic Absorption Spectroscopy (AAS). Samples were prepared by wet digestion using nitric acid, followed by Pb determination employing the standard addition method to minimize matrix interference. The analytical method was evaluated through linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy. The calibration curve exhibited excellent linearity within the investigated concentration range. The Pb concentration in the analyzed sample was found to be 0.15 mg kg⁻¹, which is below the maximum permissible limit established by the Indonesian National Standard (SNI 3719:2014). The method showed satisfactory analytical performance with an LOD of 0.1773 mg L⁻¹, an LOQ of 0.5910 mg L⁻¹, a relative percent difference (RPD) of 2.33%, and a recovery of 105.73%. These results demonstrate that the standard-addition AAS method provides a reliable quantitative determination of Pb in fruit juice matrices.
Green Synthesis and Antibacterial Activity of Silver Nanoparticles Using Ethanolic Extract from Clerodendrum fragrans Leaves
Green synthesized silver nanoparticles using plant extract (AgNPs) have emerged as promising biomaterials for biomedical applications, particularly as antimicrobial agents. This study aimed to synthesize AgNPs using ethanolic leaf extract of sarang banua (Clerodendrum fragrans) and to evaluate their physicochemical characteristics and antibacterial activity for skin-related applications. C. fragrans leaf contains secondary metabolite bioactive compounds that can be involved in nanoparticle synthesis. In this approach plant-derived phytochemicals functioned as reducing and stabilizing agents. Antibacterial activity was tested using the disc diffusion method followed by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The results of the study showed an average diameter of 114 nm with a polydispersity index (PDI) of 0.5, indicating moderate uniformity.The AgNPs showed strong inhibitory activity against Staphylococcus aureus as a representative skin-associated pathogenic bacteria with an inhibition zone of 11.06 mm. The minimum inhibitory concentration value was 3.375 µg/mL, while the minimum bactericidal concentration value exceeded 27 µg/mL, indicating bactericidal effects at higher concentrations. These findings highlight the potential of C. fragrans-mediated AgNPs as biomaterials for skin-related biomedical applications.
Antibacterial Activity, Clerodendrum Fragrans, Silver Nanoparticles
Machine Learning–Driven Discovery of Dietary Polyphenol DPP-4 Inhibitors via Molecular Docking
T2DM is a chronic metabolic disorder of rising global prevalence, in which DPP-4 serves as a key therapeutic target through its role in incretin hormone degradation. This study aimed to identify polyphenolic compounds derived from dietary sources as potential DPP-4 inhibitors through an in silico pipeline integrating machine learning (ML) and molecular docking. The bioactivity dataset for DPP-4 was retrieved from ChEMBL (CHEMBL284), processed into a binary classification dataset, and represented using 2048-bit Morgan fingerprints combined with five RDKit descriptors. Six ML models were integrated into a soft-voting ensemble, achieving a Matthews correlation coefficient (MCC) of 0.8334 and an AUC-ROC of 0.9739. Screening of 162 compounds from the Phenol-Explorer database yielded 11 potential active inhibitors. Molecular docking identified hesperetin (−8.548 kcal/mol) as the leading candidate, followed by pelargonidin, daidzein, and naringenin, with key binding residues including Ser209, Glu205/206, Tyr631, Arg125, and Tyr662.
Zeolite Synthesis From Rice Husk Ash (Oryza Sativa L.) as an NH3 Adsorbent for the Making of Eco-Friendly Cat Litter
This study aims to synthesize zeolite from rice husk ash (Oryza sativa L.) as an ammonia (NH₃) adsorbent for eco-friendly cat litter applications. The hydrothermal method was used to produce zeolite from rice husk ash and aluminum hydroxide, varying the Na₂SiO₃:Al₂O₃ ratio. The synthesized zeolites were characterized physically and chemically through moisture content, ash content, and FTIR spectroscopy analyses. Ammonia adsorption efficiency was assessed using UV-Vis spectrophotometry at initial concentrations from 5% to 25%. All zeolite variants succeeded in reducing ammonia content, with final filtrate concentrations increasing at higher initial levels. Zeolite 3 exhibited the most stable adsorption efficiency, ranging from 33% (at 5% initial NH₃) to 18% (at 25% NH₃), and was also the most crystalline with the lowest moisture and ash contents. These results indicate that synthetic zeolite derived from rice husk ash, particularly with the optimal ratio found in Zeolite 3, is highly suitable for use as an eco-friendly cat litter material, offering effective ammonia control and supporting sustainable agricultural waste utilization.
Potential of Alkaloids Isolated from Benzoin Resin (Styrax benzoin)
Benzoin resin (Styrax benzoin) is a natural product that contains various bioactive compounds, including alkaloids, which have potential antibacterial properties. This study aimed to evaluate the antibacterial potential of alkaloids obtained from benzoin resin against Staphylococcus aureus. Benzoin resin was extracted using the maceration method with 96% ethanol, followed by alkaloid screening using Mayer, Wagner, and Dragendorff reagents. Alkaloids were isolated through chromatographic separation and tested for antibacterial activity using the disc diffusion method at concentrations of 10%, 20%, and 40%. The extraction process yielded 92.13 g of crude extract with an extraction yield of 76.77%. Alkaloid screening showed positive results for all tested reagents, indicating the presence of alkaloid compounds in the extract. The alkaloid isolate exhibited antibacterial activity against Staphylococcus aureus, with inhibition zone diameters of 8.23 ± 0.38 mm, 8.93 ± 0.32 mm, and 12.43 ± 1.33 mm at concentrations of 10%, 20%, and 40%, respectively. Statistical analysis revealed that variations in alkaloid concentration significantly affected antibacterial activity (p < 0.05). These findings suggest that alkaloids derived from benzoin resin possess promising antibacterial potential against Staphylococcus aureus and may serve as a natural source of antibacterial agents.
Phytochemical Screening and Antioxidant Activity of Ethanolic Extracts of Young and Mature Butterfly Pea (Clitoria ternatea) Leaves Using the DPPH Method
Butterfly pea leaves (Clitoria ternatea) are one part of the plant that contains various secondary metabolites and have the potential to serve as a natural antioxidant source. This study aimed to determine the phytochemical content and compare the antioxidant activity of ethanolic extracts of young and mature butterfly pea leaves using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The samples were extracted by maceration using 96% ethanol, followed by qualitative phytochemical screening and antioxidant activity testing at concentrations of 20, 40, 60, and 80 μg/mL. The results showed that both extracts were positive for phenolics, flavonoids, tannins, alkaloids, saponins, and steroids, but negative for triterpenoids. The IC₅₀ values of young leaf extract, mature leaf extract, and vitamin C were 80.408, 58.023, and 5.655 μg/mL, respectively. Based on the IC₅₀ values, both extracts were classified as strong antioxidants, while vitamin C was classified as a very strong antioxidant. The mature butterfly pea leaf extract showed higher antioxidant activity than the young leaf extract, indicating that leaf maturity affects the antioxidant potential of butterfly pea leaves.
antioxidant activity, butterfly pea leaves, Clitoria ternatea, DPPH, phytochemical screening
Antibacterial Activity of Ethanol Extract of Nettle Leaves against Cutibacterium acnes and Pseudomonas aeruginosa
Acne vulgaris is a common skin disorder associated with the growth of Cutibacterium acnes and Pseudomonas aeruginosa. This study aimed to evaluate the antibacterial activity of ethanol extract of nettle leaves (Urtica dioica) against both bacteria. The extract was obtained by maceration using 96% ethanol and subjected to phytochemical screening. Antibacterial activity was tested using the disc diffusion method at concentrations of 200, 400, and 800 mg/mL. The findings demonstrated that the extract contained alkaloids, phenolics, flavonoids, steroids, and saponins. The inhibition zones against Cutibacterium acnes were 14.17±0.21 mm, 16.03±0.76 mm, and 17.37±1.33 mm, while against Pseudomonas aeruginosa they were 9.63±0.51 mm, 12.23±0.40 mm, and 14.33±0.47 mm, respectively. Statistical analysis showed significant differences among treatments (p<0.05). These findings indicated that Urtica dioica leaf extract may serve as a potential natural antibacterial agent against acne-associated bacteria.
Antioxidant Activity and Organoleptic Quality of Traditional Batak Dried Arsik Seasoning
Arsik is a traditional Batak cuisine prepared using various spices that contain bioactive compounds with potential antioxidant properties. The development of dried arsik seasoning offers advantages in terms of practicality, shelf life, and product diversification while maintaining the characteristic flavor of traditional arsik. This study aimed to evaluate the antioxidant activity and organoleptic quality of dried arsik seasoning formulated with different proportions of cayenne pepper and candlenut. Three formulations (F1, F2, and F3) were extracted using the maceration method with 96% ethanol and subsequently evaluated for antioxidant activity using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Organoleptic evaluation was conducted by 20 panelists using a 9-point hedonic scale based on color, aroma, taste, and texture attributes. The results showed that formulation F2 exhibited the highest extraction yield (57.1%) and antioxidant activity with a DPPH inhibition value of 70.2%, followed by F3 (68.9%) and F1 (36.3%). Organoleptic assessment indicated that F2 achieved the highest overall acceptance score (7.71), followed by F3 (7.25) and F1 (5.45). The higher antioxidant activity observed in F2 was associated with its balanced composition of spices, particularly cayenne pepper, which is known to contain antioxidant compounds such as phenolics and flavonoids. These findings suggest that formulation F2 is the most promising dried arsik seasoning formulation due to its high antioxidant activity and favorable consumer acceptance.
Hydrothermal Production of Furfural from Corn Husk Biomass Using an AlCl₃–HCl Catalytic System
Hydrothermal production of furfural from corn husk biomass was investigated using an AlCl₃–HCl–H₂SO₄ catalytic system. Hydrothermal treatment was carried out in a Teflon-lined reactor at 120 °C for 6 h with a solid-to-liquid ratio of 1:20 (g/mL). The catalytic system consisted of 200 mg AlCl₃, 330 µL HCl, and 110 µL H₂SO₄. Structural and chemical changes during the conversion process were analyzed using FTIR and HPLC. The results indicated partial degradation of lignocellulosic components, particularly hemicellulose, which promoted furfural formation during hydrothermal conversion. Quantitative analysis showed that furfural yield increased from 0.30% without catalyst addition to 2.37% with the AlCl₃-containing catalytic system, indicating the catalytic contribution toward hydrolysis and dehydration reactions. In addition, comparison of solvent systems showed that dimethyl carbonate (DMC) produced higher furfural yield (2.37%) than dichloromethane (DCM) (1.03%) under similar hydrothermal conditions, suggesting that solvent selection influenced furfural stabilization and conversion efficiency. Although the obtained furfural yield remained lower than values reported for optimized acid-catalyzed systems, the findings demonstrate the potential of corn husk biomass as a renewable feedstock for furfural production and provide preliminary insight into catalyst-assisted hydrothermal conversion.
Study of Thermal Oxidative Degradation of Asphalt Modified with Cyclic Natural Rubber-g-Maleic Anhydride Reactive Polymer
This study aims to investigate the effect of asphalt modification using a reactive polymer in the form of cyclic natural rubber grafted with maleic anhydride (CNR-g-MA) on the thermal oxidation resistance of asphalt. The modification was carried out ex situ by mixing the synthesized polymer with asphalt after the grafting process. CNR-g-MA was synthesized through a grafting reaction of maleic anhydride onto cyclic natural rubber using benzoyl peroxide as a radical initiator. The grafted product was characterized using Fourier Transform Infrared (FTIR) spectroscopy to identify functional groups and confirm the success of the grafting process. The modified asphalt was further analyzed using FTIR and Thermogravimetric Analysis (TGA) to evaluate changes in chemical structure and thermal stability. FTIR spectra showed characteristic absorption peaks corresponding to carbonyl and ester groups, indicating successful grafting. TGA results revealed that asphalt modified with CNR-g-MA exhibited higher thermal stability compared to pure asphalt, suggesting improved resistance to thermal and oxidative degradation.
Right Heart Failure Atrial Septal Defect (DSA) Secondary With Tricuspid Regurgitation
Congenital heart disease is a structural or functional abnormality of the cardiovascular system that is present at birth, although it can be found later in life. And the prevalence of ASD is around 9.8%. ASD is a condition where damage occurs in the inter-atrial septum, causing a connection between the left and right atrium. ASD is divided into 4 types: secundum type Atrial Septal Defect, primum type Atrial Septal Defect, sinus venosus type Atrial Septal Defect, and finally coronary sinus type Atrial Septal Defect. Secundum Atrial Septal Defect is the most common type. And generally, more often occurs in women than men with a ratio of 2:1. And the examination modalities in establishing Atrial Septal Defect include Chest X-ray, Electrocardiography and Echocardiography. The following is a case report of a 41-year-old man diagnosed with Secundum Atrial Septal Defect (ASD) + TR. This patient was diagnosed at the age of 41. In its natural course, ASD will cause pulmonary artery pressure to increase with age. ASD closure before age 24 can reduce the risk of long-term mortality to the same level as the ASD-free population. This case study aims to provide insight into diagnosis, management, and patient education to achieve optimal therapy and quality of life.
Effect of Solvent Polarity on Extraction Yield and Phytochemical Profile of Carica papaya L. Seed Extracts
Extraction efficiency of bioactive compounds from natural materials is strongly influenced by solvent polarity, which determines the selectivity of extracted secondary metabolites. This study aimed to evaluate the effect of solvent polarity on extraction yield and phytochemical profile of papaya seed (Carica papaya L.) extracts. Extraction was performed using the maceration method with hexane and ethyl acetate solvents. Extraction yield was calculated based on the ratio between extract weight and initial material weight, followed by phytochemical screening to identify major bioactive compound groups. The results showed extraction yields of 50% for hexane extract and 54% for ethyl acetate extract. Phytochemical analysis revealed that the hexane extract contained alkaloids, steroids, and triterpenoids, whereas the ethyl acetate extract contained alkaloids, flavonoids, steroids, and triterpenoids. These findings indicate that solvent polarity plays an important role in extraction efficiency and selective recovery of bioactive compounds from papaya seeds.
seeds, maceration, solvent polarity, extraction yield, phytochemical screening
Characterization of Gandapura Oil by GC and Analysis of Nitration Product Structure Using FTIR Spectroscopy
A study has been conducted on the orientation of the nitration reaction of methyl salicylate from wintergreen oil (Gaultheria Procumbens L.) with sulfuric acid catalyst. The research method was carried out through a reflux process between gandapura oil, HNO3, and H2SO4 at a temperature of 56-60°C for 60 minutes, followed by a washing and recrystallization stage using ethyl acetate. The product obtained was then analyzed using FT-IR. The nitration product is a white crystal, indicating that the compound is relatively pure with a melting point of 100-109℃. Based on the FTIR spectrum, it was confirmed that a nitration reaction had occurred with the appearance of characteristic nitrate (NO2+) absorption at 1537 cm⁻1 (asymmetric).
The Preparation and Characterization of Silica Composite Adsorbent from Palm Oil Boiler Ash and Chitosan
FTIR characterization of silica confirmed the presence of hydroxyl groups (-OH) at wave number 3386 cm-1. Wave number 1059 cm-1 Si-O-Si group, 783 cm-1, 984 cm-1 symmetric stretching vibration of Si-O-Si group, wave 452 cm-1 Siloxane group, in silica chitosan composite wide absorption band at 3356 cm-1 (-OH) group from silanol group (Si-OH) which is a functional group derived from silica as well as (-OH) and (-NH2) groups, 1628 cm-1 amide group (-NH) wave 1421 cm-1 related to symmetric bending vibration of chitosan oligosaccharide chain namely –CH2 and –CH3 groups which can be influenced by the presence of silica matrix 1079 cm-1 Si-O-Si group, wave 593 cm-1 and 488 cm-1 bending vibration of Si-O-Si and Si-O. The optimum result of Pb2+ adsorption using silica chitosan composite adsorbent was 94.70% with an absorption capacity of 1.2467 mg/g. With a concentration of 5.266 ppm it became 0.279 ppm.
Keywords: Adsorbent, Silica-chitosan Composite, Sol-Gel
Chemical Composition and Quality Parameters of Citronella (Cymbopogon nardus) Essential Oil Based on GC–MS and Physicochemical Analysis
Citronella (Cymbopogon nardus (L.) Rendle) essential oil is widely utilized in the perfume, cosmetic, and pharmaceutical industries, primarily due to its high content of citronellal, geraniol, and citronellol. This study aimed to evaluate the chemical composition and quality parameters of citronella essential oil using gas chromatography–mass spectrometry (GC–MS) and physicochemical analysis. The oil sample was obtained by steam distillation of fresh leaves and subsequently characterized in terms of specific gravity, refractive index, optical rotation, and flash point, while the chemical composition was determined based on GC–MS chromatogram peak areas. The physicochemical analysis showed a specific gravity of 0.894, refractive index of 1.477, optical rotation of −6.59°, and a flash point above 80 °C, indicating compliance with quality standards for citronella essential oil. GC–MS analysis identified 21 compounds, with trans-geraniol (70.65%), geranyl acetate (7.70%), β-citronellol (3.17%), and citronellal (1.78%) as the major constituents. These findings confirm that steam-distilled citronella essential oil exhibits good quality and a chemical profile that supports its potential for essential oil-based industrial applications.
Physical Properties of Polymer Composit Reinforced by Salak Bark Fiber (Salacca zalacca) and Nipah Bark Fiber (Nypa frutican)
Fiber composite is a material that has been widely used such as in vehicles, buildings and in industry. The use of natural fiber materials is prioritized because the costs incurred are relatively cheaper and also more environmentally friendly. This study aims to test the physical properties of composite reinforced by salak bark fibers and nipah bark fibers. The fibers are soaked using a solution of Sodium Hydroxide for 2 hours. The variation of the volume fraction used is 5% : 5% ; 5% : 10% ; 5% : 15 % ; 5% : 20%. The physical properties test carried out is a density and moisture content test. Based on the results of the study, the highest density value was 0.927 %. Meanwhile, the moisture content test value showed the highest moisture content value of 1.90%.
Characterization of the Physical and Biodegradation Properties of Biodegradable Plastic from Carboxymethyl Cellulose, Young Coconut Shells and Cassava Starch
Biodegradable plastics derived from renewable biomass were synthesized using carboxymethyl cellulose (CMC) isolated from young coconut husk and cassava starch at different CMC:starch ratios (1:1, 1:2, and 2:1). Physical characterization included tensile strength, elongation, Young’s modulus, and water resistance, while biodegradation performance was assessed through a 15-day soil burial test. The tensile strength reached its highest value at a ratio of 2:1 (2.0068 MPa), fulfilling the JIS 2-1707 requirement for biodegradable films. Elongation values were inversely related to CMC content, with the highest elongation (62.69%) observed at the 1:2 ratio. Water resistance was also optimal at the 1:2 ratio, indicating lower hydrophilicity compared to CMC-rich films. Biodegradation tests showed that bioplastics with higher CMC content (2:1) degraded fastest, achieving 97.37% mass loss on day 15. These findings demonstrate that the CMC:starch ratio significantly affects mechanical stability, moisture sensitivity, and biodegradation rate. Overall, the bioplastic films developed in this study exhibit promising properties for eco-friendly and lightweight packaging applications.
Optimization of Drying with a Food Dehydrator on the Quality of Tinuktuk Powder
Tinuktuk is a traditional Simalungun food product with immunomodulatory properties. To enhance convenience and extend shelf life, tinuktuk can be consumed as a powder produced by drying. In this study, drying optimisation was conducted using a food dehydrator at 40°C with drying times of 5, 6, 7, and 8 hours. Subsequently, tests were conducted to determine the quality of tinuktuk by analysing pH, water content, and ash content. The results showed that tinuktuk with optimal performance was obtained at 8 hours, as indicated by its pleasing texture and dryness. Specifically, the pH was 5.4, the water content was 8.20%, and the ash content was 6.31%.
Preparation of Banana Peel Activated Carbon Coated with Nanochitosan from Shrimp shells
Banana peel, an agricultural waste, contains valuable compounds suitable for use as an adsorbent to remove hazardous dyes and heavy metals from the environment. Activated carbon was prepared from banana peel using HCl as an activating agent. Chitosan was synthesized from shrimp shells through deproteinization, demineralization, and deacetylation, followed by characterization using FTIR. Nanochitosan was produced via ionic gelation and characterized using Particle Size Analyzer (PSA). The resulting nanochitosan was successfully coated onto activated carbon. FTIR analysis showed shifts in absorption intensity in both carbon and activated carbon, indicating successful activation and functional modification. The presence of chitosan was confirmed by the identification of N–H functional groups at 3248 cm⁻¹. PSA results showed that the synthesized nanochitosan had a particle size of approximately 86.14 nm. These findings demonstrate the successful synthesis of activated carbon coated with nanochitosan, with potential applications in environmental remediation through improved adsorption performance.
The Effect of Alkaline Base Activator Type on Biochar Character of Coconut Shell as a Heterogeneous Catalyst Support
Biochar derived from coconut shells shows promise as a support for heterogeneous catalysts. This study evaluated the effectiveness of alkaline activators (KOH 2 M, NaOH 2 M, and Ca(OH)₂ 2 M) in enhancing biochar properties. Biochar was produced by pyrolysis at 500 °C for 2 h, followed by chemical activation and calcination at the same temperature. The materials were characterized using FTIR, XRD, TGA, and Surface Area Analysis. Results indicate that alkaline activation modifies the biochar surface by increasing O–H, C=O, and C–O functional groups, improving polarity and adsorption capacity. The samples were predominantly amorphous and thermally stable, with minimal mass loss (0.149 mg). Among the activators tested, NaOH 2 M was the most effective, yielding a surface area of 306.233 m²/g, pore volume of 1.841 cc/g, and pore diameter of 1.202 nm. These properties suggest that NaOH-activated coconut shell biochar is a suitable carrier material for catalytic applications.
Synthesis of Zeolite from Fly Ash and Aluminum Can Waste as a Nickel (Ni) Adsorbent
Palm oil boiler fly ash and waste aluminum cans are abundant industrial residues that remain underutilized. This study aims to synthesize Y-type zeolite from boiler fly ash and aluminum can waste for application as an adsorbent to reduce nickel (Ni²⁺) content in industrial wastewater. The experiment employed variations in aluminum can mass (1 g, 2 g, 3 g) and boiler fly ash mass (60 g, 80 g, 100 g). Zeolite synthesis and its adsorption performance were evaluated in two stages. The obtained zeolite was characterized using FTIR and XRD to confirm Y-type zeolite formation, while AAS analysis determined nickel concentration. The optimal adsorption efficiency of 87.69% was achieved with 2 g aluminum can waste and 80 g boiler fly ash. These findings demonstrate that combining fly ash and aluminum waste can effectively produce zeolite Y with high potential as a sustainable adsorbent for heavy metal removal from wastewater.
Synthesis and Characterization of Liquid Natural Rubber (LNR) from SIR-10 as a Basic Material for Making Rubber Compounds
Liquid Natural Rubber (LNR) is synthesized from Standard Indonesian Rubber (SIR-10) through the process of deproteinization and oxidative degradation using phenylhydrazine/O₂. Deproteinization was carried out by the Soxhlet extraction method using acetone solvents to reduce protein content that can inhibit the degradation process. Furthermore, the rubber was oxidatively degraded and characterized using Fourier Transform Infrared (FTIR) and intrinsic viscosity measurements with an Ostwald viscometer. The FTIR results showed the emergence of new absorption bands at 3273 cm⁻¹ (O–H) and 1713 cm⁻¹ (C=O) indicating the formation of oxidized functional groups. Viscosity analysis showed a significant decrease in molecular weight from 3.717 × 10⁵ g/mol (SIR-10) to 2.375 × 10³ g/mol (LNR). These results confirmed that SIR-10 was successfully converted into LNR which has the potential to be used as a base material in the manufacture of rubber compounds.
Preparation and Characterization of Adsorbents from Tea Drains Coated With Nanochitosan From Green Mussels Shells
Tea dregs are abundant organic waste containing high cellulose content, making them a potential raw material for activated carbon production. Chemical activation using NaOH was selected to enhance adsorption capacity. Chitosan was obtained from green mussel shells through demineralization, deproteinization, and deacetylation processes. This study aimed to synthesize an adsorbent based on tea dregs activated carbon coated with nanochitosan derived from green mussel shells. Characterization was conducted using Fourier Transform Infrared Spectroscopy (FTIR) to identify functional groups and Particle Size Analyzer (PSA) to determine chitosan particle size. FTIR analysis indicated decreased absorption intensity of –OH, C=O, C–O, and C–H groups after activation, suggesting removal of organic components and increased carbon purity. The isolated chitosan exhibited NH₂ groups at 1653 cm⁻¹, while PSA results showed an average particle size of 62.08 nm. The resulting composite adsorbent demonstrated promising characteristics for water treatment, particularly in heavy metal adsorption applications.
Preparation and Characterization of Biochar from Coconut Shells with The Addition of Cu Metal as a Heterogeneous Catalyst
Biochar is a carbon-rich solid produced by pyrolyzing biomass in the absence of oxygen. This study prepared and characterized coconut shell biochar modified with copper (Cu) as a heterogeneous catalyst. Coconut shells were selected for their high carbon content and porous structure. Biochar was produced by pyrolysis at 500 °C for 2 h under nitrogen, activated with KOH (1:4 w/w), and calcined at 500 °C. Copper was introduced by impregnating the activated biochar with a Cu(NO₃)₂·6H₂O solution, stirring for 5 h, followed by calcination at 500 °C. Characterization using FTIR, XRD, SEM-EDX, and BET identified functional groups, crystal structure, morphology, elemental composition, and surface area. Results indicate that Cu addition enhances functional group intensity, sharpens XRD peaks, increases surface area, and promotes more uniform pore distribution. These changes suggest improved catalytic potential for biomass conversion, particularly in steam reforming applications.
The Effect of Acid Activator Type on Character Biochar from Coconut Shell as a Heterogeneous Catalyst Carrier
This study examines the effect of acid activators (H₃PO₄, H₂SO₄, and HCl) on the characteristics of coconut shell biochar as a heterogeneous catalyst carrier. Biochar was produced through pyrolysis at 500°C, 2M acid activation at 60°C, and calcination at 550°C, then characterized using TGA, FTIR, XRD, and BET. Acid activation increased the surface area from 4.025 m²/g to 369.335 m²/g (HCl), 359.557 m²/g (H₃PO₄), and 324.938 m²/g (H₂SO₄). FTIR showed modification of P-O, S=O, and hydroxyl-carbonyl functional groups. The crystal structure remained amorphous with HCl producing the highest intensity. HCl gave the best results with a surface area of ​​369.335 m²/g, a micropore area of ​​631.7 m²/g, and superior thermal stability (mass loss of 0.587 mg), indicating potential as a heterogeneous catalyst carrier.
Temperature Effect on Oil Solubilization Kinetics and Activation Energy of Moringa oleifera Biosurfactant Detergent
The environmental impact of synthetic surfactants in detergents has encouraged the development of eco-friendly alternatives from natural sources, such as Moringa oleifera leaves. This study aimed to determine the activation energy and evaluate the oil solubilization performance of a Moringa oleifera-based biosurfactant detergent compared with a synthetic detergent at various temperatures. The biosurfactant was prepared through maceration followed by acid activation using HCl. Product evaluation included organoleptic analysis, pH and density measurements, and kinetic analysis based on the Arrhenius equation. The results showed that the formulated biosurfactant met SNI quality standards, with pH values ranging from 8 to 10 and density between 1.176 and 1.199 g/mL. Arrhenius analysis revealed a lower activation energy for the Moringa oleifera detergent (4.16 kJ/mol) compared to the synthetic detergent (6.92 kJ/mol). These findings indicate enhanced oil solubilization efficiency and support its potential as a sustainable detergent alternative.
Kinetics of extraction of essential oils from ginger variations (Zingiber officinale Rosc.)
Ginger as one of the root plants can produce essential oils. Meanwhile, essential oils can be produced from plants. Essential oils are extracted from Emprit ginger, Red ginger and Gajah ginger using ethanol solvent to temperatures below 40°C. This research includes one-component equilibrium which includes the process of changing the molecules of substances which are influenced by changes in concentration, pressure or volume and most importantly changes in temperature. Emprit ginger tends to show order 1. Gajah ginger tends to follow order 1, while Red ginger tends to follow both orders so it is difficult to determine the right order, therefore requiring more time variations. Then the most essential oil lumps were obtained in Red ginger at 6.89 grams, Gajah ginger at 2.87 grams and Emprit ginger at 0.65 grams.