Sainteknol starting in 2024 migrates to better secure from various unwanted things, including journal hacking and so on. To submit, the author please visit the new website page of our journal at the link https://journal.unnes.ac.id/journals/sainteknol MIGRATION OFFICIAL STATEMENT HERE Published a scientific paper on the results of research and studies in the field of science and technology. Published biannually in June and December contained the writings lifted from the results of research and critical-analysis study in science and technology. Publisher: Universitas Negeri Semarang P-ISSN 0216-4566 | E-ISSN 2527-3604 Indexing GARUDA SINTA DIMENSIONS DOAJ
Performance of Natural Ventilation in Residential Buildings under Different Opening Conditions
Natural ventilation is widely applied in tropical residential buildings to improve indoor environmental quality and reduce cooling energy demand. However, increasing opening size does not always proportionally enhance ventilation performance. This study aims to experimentally determine the relationship between inlet opening variation and natural ventilation performance in a residential test room (6.0 m × 2.5 m × 3.5 m; 52.5 m³) oriented along the Southwest–Northeast axis. The investigation was conducted by measuring variations in indoor air velocity, temperature, relative humidity, and estimating the air change rate (ACH) under different inlet opening conditions. The inlet door opening was varied from 20% to 100%, while the outlet door remained fully open. Results indicate a non-linear relationship between opening variation and ventilation performance. Indoor air velocity increased from 0.09 m s⁻¹ at 20% opening to a maximum of 0.11 m s⁻¹ at 60%, then decreased at larger openings. ACH followed a similar trend, peaking at the intermediate configuration. Temperature differences remained minimal, confirming the dominance of wind-driven airflow, while relative humidity varied with airflow distribution and dilution effects. The findings suggest that moderate inlet openings may provide more efficient ventilation than fully open configurations in tropical residential buildings.
Copyright (c) 2025 Sainteknol : Jurnal Sains dan Teknologi
Synergistic Enhancement of Lignocellulosic Biomass Saccharification via Ultrasound-Assisted Pretreatment with Magnetic Fe₃O₄
The recalcitrant structure of lignocellulosic biomass necessitates efficient pretreatment strategies to enhance enzymatic saccharification for biofuel production. This study investigates a synergistic approach combining ultrasound irradiation with magnetic Fe₃O₄ for pretreating rice straw. A 2² factorial experimental design was employed to systematically evaluate the individual and combined effects of ultrasound (300 W, 30 min) and Fe₃O₄ addition (1.5 wt%). The combined treatment exhibited a pronounced synergistic effect, achieving 68.3% delignification and reducing the crystallinity index from 52.4% to 31.2%. These structural modifications resulted in a saccharification yield of 72.5%, which was significantly higher than the theoretical additive yield of 48.7% (raw: 18.5%, Fe₃O₄-only: 26.0%, ultrasound-only: 41.2%). SEM observations revealed extensive surface erosion, pore formation, and microfibril exposure after the combined pretreatment, while FTIR analysis confirmed substantial lignin removal. Furthermore, magnetic Fe₃O₄ demonstrated excellent magnetic separability, with a recovery efficiency higher than 95%, and maintained pretreatment performance over five reuse cycles with < 8% reduction in efficacy. Overall, this work presents a green, efficient, and economically promising pretreatment strategy based on synergistic ultrasound–magnetic Fe₃O₄ interactions, offering an effective pathway for enhancing lignocellulosic biomass saccharification and supporting the development of sustainable biorefinery processes.
Synthesis of Rice Husk–Based Silica Gel Using Chemical Precipitation Method as an Adsorbent for Cu²⁺ Ions
Rice husk, an abundant agricultural waste in Indonesia, is a promising source of silica. This study investigates the synthesis of silica gel from rice husks using chemical precipitation and its potential for removing copper ions (Cu²⁺) from wastewater. The silica gel was synthesized by dissolving rice husk ash in a 2 N NaOH solution, followed by precipitation with 1 N HCl. Adsorption experiments were conducted using CuSO₄ solutions at concentrations of 3, 6, and 9 ppm, with varying adsorbent masses (0.3, 0.6, and 0.9 g). The results demonstrated that increasing the adsorbent mass improved Cu²⁺ removal efficiency, with the highest efficiency observed at 0.9 g for the 3 ppm solution, achieving 86.43%. Adsorption isotherms were analyzed using the Langmuir and Freundlich models. The Freundlich model provided a better fit for the data, indicating the heterogeneous nature of the silica gel surface. This study highlights the potential of rice husk-derived silica gel as an effective adsorbent for heavy metal removal, contributing to both waste valorization and environmental protection.
silica gel; rice husk; adsorption; Cu²⁺ ions; Langmuir isotherm; Freundlich isotherm
Recycling End-of-Life (EoL) Reverse Osmosis (RO) Membranes into Ultrafiltration Membranes using Potassium Permanganate (KMnO4) for Aquaculture Water Filtration
Sustainable and economical management of aquaculture water is a significant challenge in the fisheries industry. This study aims to convert End-of-Life (EoL) Reverse Osmosis (RO) membranes into Ultrafiltration (UF) membranes using a potassium permanganate (KMnO4) solution as an oxidizing agent to enhance the efficiency of aquaculture water filtration. The conversion process involves immersing the used RO membranes in a 4,5% w/v KMnO4 solution for 3 days at room temperature. Prior to conversion, the membranes were cleaned using a 0,1% w/v Sodium Dodecyl Sulfate (SDS) solution and 0,05 M Ethylenediaminetetraacetic Acid (EDTA) to remove organic and inorganic contaminants. The results showed an increase in water flux from 20 L/m²•h to 50 L/m²•h after conversion. The analysis of aquaculture water quality after filtration using the converted UF membranes showed a significant reduction in Biological Oxygen Demand (BOD) from 5,547 mg/L to 3,817 mg/L, representing 31,2% reduction, and Chemical Oxygen Demand (COD) from 29,91 mg/L to 24,22 mg/L, representing 19% reduction. The membranes were highly effective in removing coliforms, achieving a 100% reduction from 180 MPN/100mL to 0 MPN/100mL. The values of DO and TDS decreased by only about 2%, salinity values remained unchanged, while total ammonia increased. The conversion process increases efficiency filtration, reduces operational costs, and decreases membrane waste.
reverse osmosis; ultrafiltration; membrane; aquaculture water; potassium permanganate
Mini Review: Analysis of The Influence of Work Environment on SMAW (Shielded Metal Arc Welding) Results
This study aimed to systematically investigate the influence of key environmental factors on the quality of Shielded Metal Arc Welding (SMAW) outcomes. The welding process, although widely applied across various industrial sectors, remains highly sensitive to variations in its surrounding environment. Through a systematic review of previous research, academic articles, and industrial reports, this study identified temperature, air pollution, and ventilation as the most critical environmental variables. Temperature fluctuations were found to cause weld defects such as porosity and cracking. Optimal welding performance was observed within an ambient temperature range of 10°C to 30°C, with several studies suggesting narrower optimal ranges of 15°C to 28°C or 16°C to 27°C. Temperatures below 10°C accelerated weld cooling, increasing the risk of cold cracks, while those above 30°C degraded electrode coatings, leading to porosity. Moreover, airborne contaminants—including Fe₂O₃, MnO, and CO concentrations exceeding 5 mg/m³—were shown to reduce tensile strength by 15% to 20%. Adequate ventilation, particularly using mechanical systems like local exhaust ventilation (LEV), was more effective than natural ventilation in enclosed welding environments. Integrating air filtration with precise temperature control could reduce weld defects by up to 50%. The study provides practical recommendations for improving weld quality and promoting industrial safety.
air pollution, air ventilation, shielded metal, welding
Formulation and Characterization of Urea Slow-Release Fertilizer Based on Disposable Diaper Waste with Activated Carbon as Additives
Disposable diapers are non-biodegradable waste that can pollute the environment. Disposable diapers contain super absorbent polymer (SAP) which has an absorption capacity of up to 1,000 times. SAP can be combined with activated carbon as a coating agent in urea slow-release fertilizer (SRF) production. This research aims to analyze the effect of urea SRF formulation (FA, FB, FC, and FD), with the combination of SAP and activated carbon, on the characteristics and nitrogen release behavior. SRF was characterized by Scanning Electron Microscope (SEM), Fourier Transform Infra-Red (FTIR), and Water Retention (WR) testing to determine the morphological structure, functional groups, and the ability of the sample to retain water during observation. The percentage of nitrogen release from SRF was calculated using the Kjeldahl method. The results of SEM characterization show that the thickness of the layer formed is about 63.5 µm. Different sample formulations affect the intensity of the functional groups produced. From all formulations, FD showed the highest WR and the lowest nitrogen release percentage with values of 80.2% and 20.4%, respectively. In general, it can be concluded that the combination of SAP from disposable diapers and activated carbon can be used as a coating agent in SRF production.
disposable diapers, nitrogen release percentage, SAP, SRF
Density–Porosity Interplay in Epoxy‑Based Syntactic Foams Reinforced with K15 Glass‑Silica Microballoons
Syntactic foam is a lightweight, high‑strength composite consisting of a polymer matrix filled with hollow microspheres (microballoons). This study examines how the volume fraction of glass‑clad silica microballoons K15 (10–50 vol %) affects the density, porosity, and void distribution of epoxy‑bonded syntactic foams. Specimens were molded in accordance with ASTM D790, conditioned for 48 h (23 ± 2 °C; 50 ± 5 % RH), and their density was measured by the pycnometric method specified in ASTM D792. Porosity was calculated theoretically and validated by SEM–EDS imaging of fracture cross‑sections. Results show a linear decrease in density from 1.15 g cm⁻³ (0 vol %) to 0.63 g cm⁻³ (50 vol %), while porosity rises exponentially from 2.7 % to 18.4 %. Morphological analysis confirms a homogeneous microballoon dispersion up to 30 vol %, but agglomeration and interbinder voids appear above 40 vol %, leading to uncontrolled porosity. A strong negative correlation (R² = 0.96) is observed between density and effective porosity. A 30 vol % K15 loading is identified as the optimum, achieving a 28 % density reduction without a significant porosity spike. These findings provide a basis for designing sandwich cores and amphibious flotation structures that require high strength‑to‑weight ratios.
syntactic foam; hollow glass microspheres; K15 microballoons; density and porosity relationship; epoxy composites; lightweight core materials
Cron Job Implementation for Automated Data Processing and Transfer in Cloud Infrastructure
The rapid growth of cloud computing has necessitated efficient and automated solutions for data management in cloud infrastructure. Manual data processing and transfer methods are prone to delays, errors, and inefficiencies, particularly in real-time applications. This study proposes a systematic approach to automate data processing and transfer using cron job, PHP script logic, and Cloud Panel integration. A MySQL database was designed with two tables: data_now for real-time data and data_one_hour for scheduled transfers at one-hour intervals. Php script were developed to automate data transfer logic, while cron job were configured on the Cloud Panel to execute these scripts at predefined intervals. The system was tested in a cloud environment, demonstrating error-free, hourly data transfers with significant improvements in efficiency, accuracy, and timeliness. Results showed that the automated system reduced manual workload, ensured real-time data consistency, and optimized resource utilization. This study provides a scalable and reliable framework for automating data workflows in cloud-based systems, offering practical solutions for industries such as healthcare, finance, and IoT. The findings contribute to the field of cloud automation by presenting a robust approach that can be readily implemented across various organizational infrastructures.
Implementation of Hierarchy Attribute-Based Encryption (HABE) to Secure Information Stored in Cloud Storage
The usage of cloud storage is currently growing, particularly for media used for information storage. Information saved in cloud storage makes it possible for the owner of the cloud storage to access the Information without the owner's permission. The privacy of access and management of access to the information kept in the cloud storage becomes a problem and security risk when using that cloud storage because the owner cannot ensure that the stored information is only accessed by authorized parties. Access control management is necessary for information owners to guarantee the safety of the information they hold. To regulate access to information kept in cloud storage, this study intends to apply the Hierarchy Attribute-Based Encryption (HABE) technique. A hierarchical attribute base is used to encrypt and decode information saved in cloud storage through the application of HABE, making hierarchical attributes the essential element in controlling access to the information. The hierarchical structure utilized to manage access control for information security will also be detailed in this research. This implementation procedure is completed before the information is stored in cloud storage. The mathematical computations used to secure text information during the encryption and decryption operations are described in the HABE implementation method and debate. By using Hierarchy Attribute-Based Encryption, security concerns with cloud storage can be resolved and flexible access control management in compliance with corporate standards is made possible.
Information Security, Cloud Storage, HABE, ABE, Cryptography
Design of ACS712-based Current Sensing Monitoring Evaluation for PWM Solar Charge Controller
The rise of renewable energy has led to growing interest among researchers in optimizing renewable energy systems to harvest the highest possible energy output, especially in photovoltaic (PV) systems. Photovoltaic systems generate energy from sunlight, but the intermittent nature of sunlight poses a challenge for providing constant power. Another problem is that the most affordable conventional Pulse-Width Modulation (PWM) controllers on the market are unable to provide a current monitoring system. This issue is critical when users require detailed data to perform diagnostics on their PV systems. In this study, a monitoring system using microcontrollers and the ACS712 current sensor was developed and implemented to observe the behavior and performance of a photovoltaic (PV) charging system based on the current output from a PWM controller. The primary objective of this system is to develop a solution that can identify PV modules operating under suboptimal conditions, which can be caused by various factors such as increased solar cell temperature, cloud cover effects, PV module degradation, and the performance of the Pulse-Width Modulation (PWM) solar charge controller (SCC). This is crucial because PV modules can be susceptible to various environmental and technical factors that may impact their efficiency and power output. By closely monitoring the performance of each PV module using the ACS712-based current sensing system, the researchers aim to promptly detect and address any issues that may arise, ensuring the overall optimal operation of the PV system.
ACS712, Current Sensing, PWM, Solar Charge Controller, Solar PV
Copyright (c) 2024 Sainteknol : Jurnal Sains dan Teknologi
Effect of Acid-Base Composition on Physical Characteristicsand Antioxidant Activity of “Beras Kencur” EffervescentTablet
This study aimed to evaluate the effect of acid-base ratio on the physical characteristics and antioxidant activity of the beras kencur effervescent tablet formulation. The formulation determination was based on the percentage inhibition value, where the highest value (76.2%) was found in beras kencur at 10 mg/mL, so that 1.5 g is needed to achieve the highest potential of radical scavenging activity. In this case, 1.5 g of sample was then incorporated into three effervescent tablets. The acid-to-base ratios used in this study were 1: 1.25 (F1), 1: 1.50 (F2), and 1: 2.50 (F3). The tablets were evaluated for pH, dissolution time, total phenolic content (TPC), and antioxidant activity. The results showed that a higher proportion of base (F3) improved solubility. Meanwhile, antioxidant activity evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test, and total phenolic content determined using Folin-Ciocalteau, showed that tablets with a higher proportion of acid exhibited higher total phenolic content. However, considering that all three samples have very strong antioxidant activity, it can be concluded that F3 is the optimal formulation.
Comparison of the Use of YOLOv11 Variations in the Empty Parking Spaces Detection System
The development of a smart parking system using the You Only Look Once (YOLO) model has improved the efficiency of parking management by providing real-time vehicle detection and availability of parking spaces. This study compared three variations of YOLOv11-Nano (YOLOv11n), YOLOv11-Small (YOLOv11s), and YOLOv11-Medium (YOLOv11m) to determine the most effective model in detecting empty parking spaces. The experiment was carried out using a dataset consisting of 5725 images of parking areas with various conditions such as angles, lighting, and distance. In addition, the researcher also used a 6-second parking lot timelapse video for the test material of the model that had been trained. The results show that each variation of YOLOv11 has its own advantages in terms of accuracy, speed, and computing efficiency. YOLOv11n offers faster detection with lower resource consumption, while YOLOv11m provides higher accuracy with longer processing times. The findings of this study aim to help select the optimal YOLOv11 variant for smart parking implementation, thereby improving efficiency and accuracy in real-world applications.
Optimization Formula of Collagen Nanoemulgel from WasteMilkfish (Chanos chanos) Bones as Antiaging
Climate change has negative impacts throughout the countries in the world, especially Indonesia, which has a tropical climate. Successful aging can be achieved by building individual self-confidence through prevention and skin aging. Indonesia is a producer of milkfish waste, reaching 5.4 tons/year, which is in line with the increasing center of "Otak-otak" milkfish souvenirs found in Gresik. The waste, especially fishbones, can be synthesized into collagen. The characteristic fishbone collagen waste are in the form of large porous sheets, while particle size is an essential factor in the absorption effectiveness of cosmetics. Therefore, Nanoemulgel is able to overcome this problem. This research aims to produce best collagen nanoemulgel from milkfish bone by physical evaluation with varying ratios of surfactant: cosurfactant in collagen nanoemulgel. The research method was done experimentally by comparing the components Tween 80: PEG 400 F1 (30:30), F2 (40:20), and F3 (35:15) through qualitative and quantitative physical characteristics using one-way anova. Evaluations whose results differ significantly are pH on the 7th day, spreadability, and viscosity. Research results show F2 is the best formula and meets physical stability specifications : particle size 3.89 nm, PDI 0.1906, zeta potential -0.2 mV, pH 4.7±0.04, viscosity 890.1± 4.26 cps, spreading 5.93±0.23 cm.
Antiaging, Collagen, Milkfish, Nanoemulgel, Physical Characterization
Optimization of Alkaline Water Production from Rainwater through Electrolysis Method: Effect of Voltage and Time on pH and TDS
Alkaline water is known to have health benefits due to its higher pH than ordinary water. In this study, the production of alkaline water from rainwater using electrolysis method was optimized, with variations in voltage and time to evaluate its effect on pH and Total Dissolved Solids (TDS). The experiment involved three voltage levels (12 Volt, 24 Volt, and 36 Volt) and three time intervals (10 minutes, 20 minutes, and 30 minutes). The results showed that increasing the voltage and electrolysis time contributed significantly to the increase in water pH, which reached the highest value at 36 Volt for 30 minutes. However, increasing the voltage and time also increased the TDS value linearly, which can affect the water quality if it exceeds a certain limit. This study concludes that the optimal voltage for producing alkaline water with suitable pH and TDS is 24 Volt with an electrolysis time of 20 minutes. Thus, this method offers an efficient and simple solution to produce alkaline water from rainwater, which could potentially benefit public health in areas with limited access to high-quality drinking water.
Alkaline water, rainwater, electrolysis, pH, TDS, voltage, time.
The Effect of Environmental Conditions on the Alkaloid andFlavonoid Content of Basil Leaves (Ocimum basilicum L)Growing in Kandangan Village
Basil leaves have long been used as fresh vegetables. Basil leaves are used to eliminate odors and can also be used as antiseptics. Each plant can produce primary and secondary metabolites. The production of these metabolites is influenced by environmental conditions. Kandangan Village is one of the villages in Gresik Regency which has a relatively hot temperature and many industries are located around it. The purpose of this study was to determine the results of phytochemical screening tests for the presence of alkaloid and flavonoid compounds in basil leaves growing in Kandangan Village. This type of research is experimental research. Basil leaf samples were obtained from Kandangan Village. The extraction method used was maceration using 96% ethanol solvent. The test for the presence of alkaloids used the Dragendroff test method and the Mayer test. The test for the presence of flavonoids used the Wilstater test method and the Bate Smite-Metcalfe test. The results of this study indicate that basil leaves growing in Kandangan Village are positive for the presence of flavonoids with a color change to yellow for the Wilstater test and a color change to red in the Bate Smite-Metcalfe test. However, the test for the presence of alkaloids showed negative results because there was no formation of orange to red deposits for the Dragendroff test and yellowish white deposits for the Mayer test.
Dragendorff test, Wilstater test, Mayer test, Smite-Metcalfe test, Ethanol, Maceration
Cr(VI) Removal Using A Dual Chamber Microbial Fuel Cell
Chromium ions is notably a hazardous heavy metal due to its toxic and carcinogenic nature, particularly in its hexavalent form, Cr(VI). One of the major Cr(VI) pollution source is from electroplating industry effluent, which may contain high concentrations that pose a risk of contamination of aquatic and soil ecosystems if not treated carefully. One of the alternative method known to be able to treat Cr(VI) wastewater is by using microbial fuel cell (MFC). This research focused on on the removal of Cr(VI) from synthetic electroplating wastewater using a 4L dual-chamber MFC under fed-batch condition, as well as investigating the impact of mixed liquor suspended solids (MLSS) and chemical oxygen demand (COD) concentrations to its performance. Observed parameters include the efficiency of Cr(VI) removal and power density. Septage sludge and acetate were both used as biomass and substrate source respectively. Based on this research, it can be concluded that the highest Cr(VI) removal efficiency and power density were achieved using specific MLSS and COD concentration that resulting in F/M ratio of 0,459 to 0,489 gCOD/gMLSS. From initial Cr(VI) concentration of 50 mg/L, the highest removal was obtained by MFC running with initial MLSS and COD concentrations of 3.500 and 1.500 mg/L respectively, achieving 62,17% over 312 hours. This setup also produced the highest power density of 48,22 mW/m².
Dual Chamber; Microbial Fuel Cell; Power Density; Septage Sludge
Experimental Investigation on Reduction of High Combined Water Contained Iron Ore by Ammonia-Methane-Mixed Gas
Reducing CO₂ emissions in the steel industry, which contributes 7% of global emissions, is crucial. Ammonia, as a hydrogen-based reducing agent offers one promising solution to address the decarbonization challenge in primary ironmaking process due to its high hydrogen storage density and ease of transport. However, for subsequent steelmaking process, the lack of carbon in the reduced ore from the ammonia-hydrogen iron reduction system must be addressed. In this study, we reduced iron ore using an ammonia-methane mixed reducing gas to introduce carbon into the reduced ore, from the raw material of porous ore prepared from a high combined water, goethite ore. We varied the reduction conditions to investigate how the reaction and carbon content would change, aiming to optimize the reduction process and enhance carbon content in the reduced iron. The results show that ammonia is primarily consumed for iron reduction, facilitated by hydrogen from its decomposition, while methane decomposes into carbon and hydrogen. Methane decomposition begins around 800°C, significantly increasing the ore's carbon content. Higher temperatures accelerate both reduction and carbon incorporation. The ammonia-methane mixing ratio influences reduction efficiency and carbon content, with a higher ammonia ratio expediting these processes. At 850°C, a 1:1 ammonia-methane mixture yields higher carbon content than higher ammonia ratios. This study highlights the potential of ammonia-methane mixed gases for sustainable steel production by enhancing the reduction and carbonization of high-CW-content iron ores.
Synthesis of Glycerol Monooleate with MgO-Impregnated Natural Zeolite Catalyst
Glycerol Monooleate (GMO) is synthesized via esterification, which involves the reaction between glycerol and oleic acid to yield monoglyceride esters. The esterification reaction is intrinsically slow, requiring the use of a catalyst to decrease the activation energy. The catalyst used in this study is a naturally occurring zeolite catalyst that has been altered through acid treatment and impregnation with Mg(NO3)2, and then subjected to calcination to convert it into MgO. Typically, this research consists of two steps: an initial phase where a natural zeolite catalyst is altered, followed by a subsequent phase where glycerol monooleate production. This study investigates the effects of different variables on the reaction. The variables include temperature (140–180oC), catalyst loading (3-10 %weight), glycerol to oleic acid ratio (2:1, 3:1, 4:1), reaction time (0–180 minutes), and stirring speed (125-525 rpm). The research results demonstrate that the highest conversion rate was achieved with a temperature of 180oC, a catalyst concentration of 10%, and a reactant ratio of 3:1 (glycerol to oleic acid). The ideal response time was found to be 120 minutes. The reaction kinetics can be estimated by employing a pseudo reaction equation that follows a first-order rate law. The rate constant, represented by k', can be approximated using the Arrhenius equation. The reaction has an activation energy of -18.64 kJ.mol-1, and the value of A is 1.41 cm3.g-1.minute-1.
Ultrasound Assisted Ethanolic Extraction of Ipomoea reptans Poir Leaves Antioxidant Activities, Total Phenolic and Flavonoids
Ipomoea reptans Poir leaves contain phenolic and flavonoid compounds that can reduce free radicals and prevent diseases such as cardiovascular disease, coronary heart disease, and cancer. The drawback of conventional extraction is that it takes a long time, so a shorter extraction method is needed, one of which is the ultrasonic method. This study aims to test the antioxidant activity of ethanol extract of Ipomoea reptans Poir leaves extracted by ultrasonic method and determine the total phenolic and flavonoid content. Ipomoea reptans Poir leaves were extracted using the ultrasonic method at 50oC for 30 minutes with 70% ethanol solvent to obtain ethanol extract of Ipomoea reptans Poir leaves. Antioxidant activity test of ethanol extract of Ipomoea reptans Poir leaves using DPPH method and vitamin C as a comparison. Determination of total phenolic content using gallic acid with a maximum wavelength of 745.20 nm and operating time of 120 minutes. Determination of total flavonoid content using quercetin with a wavelength of 439.60 nm and operating time of 30 minutes. The results showed that the antioxidant activity of Ipomoea reptans Poir leaves obtained an IC50 value of 40.62 ppm (very strong). Total phenolic and flavonoids were 78.33 mgGAE/g extract and 1.03 mgQE/g extract.
Antioxidant, Phenolics, Flavonoids, Ultrasound extraction, Ipomoea reptans Poirs
Effervescent Powder Formulation of Ethanol Extract of African Leaves (Vernonia amygdalina) as an α-amylaseInhibitor
Vernonia amygdalina or African leaves are reported to have many biological activities, including antidiabetic. However, there are still many people who have not used this plant as an antidiabetic treatment. This research aims to create a medicinal preparation formula in effervescent form with the main ingredient being African leaves. Testing of the dosage formula includes organoleptic tests, water content, pH, and dispersing time. The research results showed that one of the three formulas had better stability after 7 days of storage. After 7 days of storage, the color of the formula became lighter, the pH value changed slightly (7-8), the water content was 2.3% and the dispersion time was 2.00 minutes. This formula can be used as input for further research regarding testing its activity as an antidiabetic through inhibiting alpha-amylase in vitro.