The availability of fossil fuels is increasingly diminishing, while the global energy demand continues to rise. Alternative energy sources currently available from various vegetable oils include jatropha, palm, kapok seed, coconut, and cottonseed oil as substitutes for fossil fuels. When used directly in diesel engines, these oils can lead to several issues, including high viscosity and elevated flash points, which hinder proper fuel combustion and result in carbon deposits within the combustion chamber. Several solutions have been proposed to address these issues, including blending vegetable oils with diesel fuel at various ratios, preheating the vegetable oils, mixing them with additives, and utilizing exhaust gas recirculation and combustion chamber modification. This study investigates the role of bio-additive and applied magnetic fields in influencing flame characteristics and hydrocarbon gas emissions during palm oil droplet combustion. The experimental procedure involved direct testing on palm oil by incorporating a 3% eucalyptus oil-based bio additive and applying an attractive magnetic field (U-S), with droplet diameters ranging between 0.3-0.4 mm. Thermocouples diameter of 0.12 mm were placed on both sides of the magnet with a magnetic field intensity of 1.1 Tesla, and heating wires as the heat source were positioned beneath the thermocouples. The study found that combining eucalyptus oil bio-additive and an attractive magnetic field (U-S) resulted in the shortest flame evolution time of 1760 ms. The flame height and hydrocarbon gas concentration also reached their lowest values at 5.74 mm and 296 ppm, respectively. Meanwhile, the same treatment produced of highest temperature of 846.5 °C compared to other experimental conditions.

Red snapper (Lutjanus bitaeniatus) is a source of animal protein with a high-water content, making it prone to spoilage. Spoilage can be prevented through preservation. Garlic can be used as a natural preservative for fish because it contains antibacterial substances, including allicin, which plays a role in inhibiting and killing spoilage bacteria, as well as other antimicrobial compounds such as alkaloids, flavonoids, saponins, and tannins. This study aims to determine the effect of garlic extract as a natural preservative on the protein profile of red snapper. The research design was divided into five parts: fresh red snapper stored for 24 hours without soaking, and three parts soaked in garlic extract at concentrations of 5%, 10%, and 20%, respectively. This type of research was experimental. The research method was the preparation of garlic extract at concentrations of 5%, 10%, and 20%. Protein concentration was calculated using the Bradford method, followed by SDS-PAGE to separate proteins based on their molecular weight. The SDS-PAGE results were analyzed using the GelAnalyzer 19.1 application to calculate the molecular weight of the proteins and the protein profiles of the treatments compared to fresh fish. The results showed that the highest protein concentration was found in the 5% garlic extract treatment compared to the 10% and 15% concentrations. The protein profiles of fresh snapper and the 5% garlic extract treatment were not significantly different from fresh red snapper, with 13 protein bands (9 major bands and four minor bands). In contrast, fresh red snapper had 16 protein bands (13 major and three minor bands). This study concludes that garlic extract immersion treatment can be used as a natural preservative, with the optimal concentration being 5% garlic extract.

Perovskite solar cells (PSCs) have gained significant attention due to their remarkable power conversion efficiency (PCE) and potential for low-cost, scalable production. Despite this progress, further efficiency enhancement requires systematic optimization of device architecture, particularly the thickness of functional layers. This study presents a numerical simulation using the OGMANANO simulation platform to investigate the influence of layer thickness variation, specifically in the perovskite absorber layer, electron transport layer (ETL), and hole transport layer (HTL), on the performance of planar PSCs. The simulation models a typical n-i-p structured device under standard AM1.5G illumination, evaluating key photovoltaic parameters such as short-circuit current density (Jsc), open-circuit voltage (Voc), fill factor (FF), and overall PCE. Results indicate that the optimal absorber thickness lies in the 500–600 nm range, with a peak efficiency of 22.7% achieved at 550 nm. Furthermore, ETL and HTL show optimal performance at 50 and 60 nm, respectively, minimizing recombination losses and enhancing charge transport. The study concludes that precise layer thickness control is critical for maximizing PSC efficiency. The use of OGMANANO proved effective in simulating multilayer perovskite structures, providing a reliable tool for pre-fabrication optimization in advanced solar cell design.

We are delighted to present the December edition of our journal (Volume 16, Number 1, December 2025), which showcases a rich collection of interdisciplinary research in biomedical engineering, environmental technology, renewable energy, materials science, and applied biological sciences. The studies featured in this issue reflect the dynamic landscape of technoscientific inquiry, highlighting both fundamental advancements and practical solutions to contemporary challenges.We open this edition with an in silico exploration of boswellic acid as a potential antibacterial agent against Cutibacterium acnes and other acne–associated pathogens. Through molecular docking targeting nine key bacterial proteins, the study demonstrates that boswellic acid exhibits strong binding affinity, particularly to the transcriptional regulator TcaR, suggesting its promise as a topical antibacterial candidate. This work underscores how computational biomedicine continues to accelerate the discovery of safer and more effective dermatological agents....To close this edition, we present a study on Constructed Wetlands (CW) using roof–tile fragments and Echinodorus palaefolius for treating phosphate–rich laundry wastewater. Remarkably, the system achieved a 99.96% reduction in phosphate levels, driven by adsorption, biodegradation, and microbial interactions—particularly from Proteus and Citrobacter species.Together, the articles in this issue reflect the dedication of researchers in advancing science and engineering for societal benefit. As we close this final issue of the year, we would also like to extend our warmest wishes to all our readers, authors, and reviewers. May this holiday season bring rest, reflection, and joyful moments with your loved ones. We look forward to welcoming you again in our June 2026 edition with new research contributions and advancements across the technoscience fields. Warm regards,Editor in ChiefJurnal Teknosains

A Constructed Wetland (CW) is a modified wastewater treatment system that can be applied anywhere. The advantages of CW systems are low operational costs, naturally available constituent materials and provide aesthetic value as a wastewater treatment solution. The increasing number of laundry industries causes high concentrations of phosphate pollution in the environment. Shards of tile as an adsorbent may reduce the concentration of Total Suspended Solid (TSS), Total Dissolved Solid (TDS), Chemical Oxygen Demand (COD), phosphate, Methylene Blue Active Surfactant (MBAS), and sulphate. The effect of adding tile fragments is supported by using Water Jasmine plants (Echinodorus palaefolius) and the diversity of microorganisms attached to the adsorbent. The results of this study showed a phosphate reduction efficiency of 99.96%. The presence of the bacterial genus Proteus sp. and Citrobacter sp. on the tile fragments adsorbent impacts phosphate reduction. Pollutant removal in CW systems occurs due to adsorption, sedimentation, filtration, biodegradation and precipitation.

The simpur air plant (Dillenia suffruticosa) is one of the plants used in traditional medicine to treat various diseases and has potential as an antioxidant. Antioxidants are compounds that inhibit, prevent, and reduce oxidative damage to target molecules. The effectiveness of extracting active compounds depends on the extraction method used. Maceration requires a relatively long duration, so faster and more efficient alternatives, such as MAE, are needed. However, heat-sensitive compounds may degrade if the power is too high or the extraction time is prolonged. Therefore, a comparison between maceration and MAE methods is necessary. This study aims to determine the effect of maceration and MAE on the antioxidant activity of the methanol extract from the simpur air leaves. Samples were then analyzed using TLC with a mobile phase of toluene, ethyl acetate, and formic acid (3:5:1 v/v/v). Antioxidant activity was assessed using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay, and data were analyzed with SPSS. TLC results confirmed the presence of flavonoids indicated by a yellow color after spraying with AlCl3, with IC50 values supporting their antioxidant potential. The Rf values of extracts obtained by maceration and MAE with the rutin standard (0.22) and quercetin standard (0.8). The MAE method produced higher antioxidant activity than maceration, with IC₅₀ values of 5.942 ± 0.345 μg/mL and 10.498 ± 0.213 μg/mL, respectively, both classified as strong antioxidants (IC50 < 50). Independent sample t-test analysis yielded a p-value of less than 0.05, indicating a significant difference between the two methods. The methanol extract of simpur air leaves extracted by the MAE method produces better antioxidant activity than the maceration method.

Surface water pollution caused by the discharge of domestic wastewater, including that from hospitals, is a serious issue that threatens public health and environmental quality. Hospital wastewater typically contains high concentrations of organic matter (COD, BOD), suspended solids (TSS), and pathogenic compounds that may exceed the quality standards set by the Ministry of Environment and Forestry, as outlined in Regulation No. 68 of 2016. This study aims to evaluate the performance of a combination of a Moving Bed Biofilm Reactor (MBBR) using Kaldness K1 media and a Lamella Clarifier in reducing COD, BOD, and TSS levels, as well as stabilizing the effluent pH of hospital wastewater at the laboratory scale. The research employed an experimental approach, utilizing a laboratory wastewater treatment plant design comprising MBBR and Lamella Clarifier units. Wastewater samples were collected by grab sampling from the hospital treatment plant inlet, then diluted to varying concentrations of 20%, 30%, and 50%, and subjected to a 24-hour retention time. The analyzed parameters included COD, BOD, TSS, and pH. The treatment results were statistically analyzed using a paired t-test to assess the significance of concentration reductions before and after treatment. The results indicated that the combination of these two units achieved average reductions of BOD by 56%, COD by 34%, and TSS by 53%, with effluent pH between 7.3 and 7.6, meeting quality standards. Statistical analysis revealed significant differences (p < 0.05) between inlet and outlet conditions, indicating the system's effectiveness. Therefore, the integration of MBBR and Lamella Clarifier is considered a viable solution for efficient, stable, and regulation-compliant hospital wastewater treatment.

Acne vulgaris (AV) is a common inflammatory-skin disorder associated with bacterial infections, particularly Cutibacterium acnes, Staphylococcus aureus, and Staphylococcus epidermidis. The rising resistance to conventional antibiotics has prompted the exploration of natural compounds such as boswellic acid, which is known for its antibacterial potential. This study aimed to evaluate the antibacterial activity of boswellic acid using an in-silico approach through molecular docking against several essential bacterial target proteins implicated in acne pathogenesis. The boswellic acid ligand was obtained from the PubChem database, while the three-dimensional structures of the target proteins were retrieved from the RCSB Protein Data Bank. Blind docking was performed using AutoDock Tools version 1.5.7 and AutoDock Vina, followed by interaction analysis using Discovery Studio Visualizer and Visual Molecular Dynamics (VMD). Nine bacterial proteins involved in vital cellular processes such as metabolism, protein synthesis, biofilm formation, and DNA replication were selected, including transcriptional regulator TcaR, penicillin-binding proteins (PBPs), tyrosyl-tRNA synthetase (TyrRS), 3-ketoacyl-ACP synthase III (KAS III), CRISPR-associated protein, DNA gyrase, transcriptional regulator MarR, methylmalonyl-CoA epimerase, and accumulation-associated protein (Aap). The docking results demonstrated that all target proteins exhibited negative binding energy values (< 0), indicating thermodynamically stable and spontaneous interactions. Among these, TcaR displayed the highest binding affinity with a binding energy of −10.2 kcal/mol and formed nine conventional hydrogen bonds, reflecting a particular and stable interaction. Key interacting residues included Gln: B61, HisA:42, AsnA:20, AsnB:17, and Arg1:110. In contrast, the Aap protein formed only one covalent bond, indicating the weakest interaction. These findings suggest that boswellic acid effectively inhibits key bacterial proteins, particularly those involved in transcriptional regulation and biofilm development. Therefore, boswellic acid holds significant potential as a safe and effective topical antibacterial agent for further growth in biomedical engineering-based formulations.

Composite resin restorations frequently fail due to secondary caries formation. To address this, the antibacterial potential of chitosan for incorporation into dental composites has been explored. Given the limitations of existing studies—which often lack a focus on biomechanical function, this research used an in silico Finite Element Analysis (FEA) to evaluate the combined effects of chitosan addition and cavity dimension on stress and strain distributions within restorative materials. A 3D model of a human mandibular first molar, derived from micro-CT scanning, was subjected to FEA using varying chitosan concentrations (0%, 0.5%, 1.0%, and 2.0%) and two cavity dimensions (conservative and extensive). Statistical results showed significant differences in stress and strain distributions across the treatment groups. Cavity dimensions significantly influence the distribution of stress and strain. The effect of chitosan addition is secondary. The addition of chitosan in cases of extensive cavities was not strong enough to produce statistically significant changes. The FEA analysis demonstrates a clear influence of cavity geometry on biomechanics: In extensive cavities, the restorative material provides superior structural reinforcement, leading to a stiffer composite unit (high stress, low strain) and limited cusp deformation; while in conservative cavities, the structure exhibits a highly flexible response to loading (low stress, high strain), even with a preserved marginal ridge. The stress concentration in the tooth model was primarily in the cervical area, specifically at the cementoenamel junction (CEJ).

Ultrafine bubbles (UFBs) play a crucial role as catalysts in water treatment, pharmaceuticals, biomedical engineering, and industrial processes, particularly those involving heat transfer mechanisms. Several researchers in Indonesia have explored ultrafine bubble fluids' potential as a heat transfer medium in passive cooling system models. In this context, changes in the density of ultrafine bubble fluids serve as the primary driver for flow. Since ultrafine bubbles increase in diameter when heated, examining an optimal production model is essential to ensure their availability in the flow. This study aims to optimize the production of ultrafine bubble fluids with the lowest possible density compared to the base fluid (reference). The research investigates the effect of production time and volume variations on ultrafine bubble density in a closed-loop system. Production times of 30, 60, 90, 120, 150, and 180 minutes are tested across tank volumes of 20, 40, 50, and 60 liters. The closed-loop production model utilizes hydrodynamic cavitation to maintain continuous fluid flow, with sample collection occurring at 15-minute intervals after the initial production time to allow for stable bubble size. Observations and statistical analysis using the Response Surface Method (RSM) reveal a nonlinear relationship between production time and ultrafine bubble fluid density. The optimal density is achieved with a production time of 60 minutes for a 40-liter volume. Additionally, this closed-loop model increases the temperature of the ultrafine bubble fluid to 54.3 °C in a 20-liter volume. Heat accumulation occurs due to the continuous pump-driven flow without additional cooling systems.