Jurnal Beta Kimia

Optimization of Extraction and Measurement Methods in the Determination of Total Iron (Fe) Content in Anti-Anemia Multivitamin Capsule Samples

Rohmat Ismail — 2025-05-10

Iron (Fe) is a transition metal that plays a critical role in human life, particularly as a micronutrient. The objective of this study is to optimize and ascertain the most appropriate method for measuring the total Fe content of anti-anemia multivitamin capsule samples, thereby ensuring the accuracy of the measurement results. The determination of total Fe content can be achieved through two metal extraction methods, namely wet digest and dry ashing methods, and two metal measurement methods, namely UV-Vis spectrophotometer and atomic absorption spectrophotometer (AAS). The findings revealed that the measurement of total Fe content by UV-Vis spectrophotometer through the dry ashing extraction method yielded a lower value (20.92 ± 0.29 mg/g) compared to the wet digest method (67.91 ± 0.83 mg/g). Furthermore, the Fe content determined by AAS analysis exhibited a reduced value in the dry ashing extraction method (1.42 ± 0.02 mg/g), while the wet digest extraction method yielded a substantially higher value (72.91 ± 4.12 mg/g). Statistical tests with the Duncan method revealed that the wet digest extraction method with UV-Vis spectrophotometer measurements is the most effective method for determining the total Fe content, with a significance level equivalent to the theoretical reference value (67.85 ± 0.03 mg/g).

The Role of Problem-Based Worksheets in Enhancing Students’ Critical Thinking Skills

Sudirman Sudirman — 2025-05-05

Research has been conducted with the aim of being able to determine the effect of Problem Based Learning (PBL) based LKPD on the critical thinking skills of students in class XI IPA. The subjects in this study were students of class XI IPA totaling 30 people. This research was conducted in a way that the control class applied LKPD which was taught with a conventional learning model while the experimental class applied LKPD based on PBL learning model which was conducted for 3 meetings. The t-test results obtained sig.2 tailed value < 5% significant level before treatment 0.007 ≤ 0.05 then H1 is accepted and H0 is rejected, while after treatment is 0.160 ≥ 0.05 then H0 is rejected and H1 is accepted. Thus it can be concluded that LKPD based on problem-based learning (PBL) does not significantly affect the critical thinking skills of students in class XI IPA. However, the results of the N-gain Score Test show that the mean value of the N-gain Score in the experimental class is 12.73 higher than the control class which is only 8.73. Thus it can be concluded that the use of PBL-based LKPD has an effect on the experimental class and can improve critical thinking skills by 12.73 compared to the control class which can only increase by 8.73 after learning takes place.

Influence of Problem-Based Learning Models Improving Students’ Problem-Solving Skills

Daud Dakabesi — 2025-04-22

One cognitive skill needed to meet the demands of the complex and dynamic development of the twenty-first century is problem-solving. Therefore, this research aimed to investigate how well 126 students understood chemical difficulties about reaction rate material both individually and collaboratively. Only a posttest is applied in this study's quasi-experimental research design. Sixty-two learners in the experimental class received treatment using a Problem-Based Learning (PBL) model, while sixty-four learners in the learning control group received treatment using traditional methods. According to the findings, pupils in the experimental class were more adept at solving problems than those in the control group. The study's findings also show how collaborative problem-solving significantly aids students' attempts to solve chemical challenges.

The Antioxidant Activity of Ethanol Extract of Chinese Betel Leaf (Peperomia pellucida) using the DPPH Method with Potential as an Antidiabetic Agent

Fahmi Sadik — 2025-05-10

Complications of diabetes mellitus are known to be exacerbated by oxidative stress. The Chinese pepper plant (Peperomia pellucida), known as a source of natural antioxidants, was studied for its potential in this research. We evaluated the in vitro antioxidant capacity of the ethanol extract of P. pellucida leaves using the DPPH method to see its relationship with antidiabetic potential. The process involves extracting the leaves using ethanol, followed by testing the extract's ability to scavenge DPPH free radicals at various concentration levels to determine the IC₅₀ value. It was found that the ethanol extract showed antioxidant activity with an IC₅₀ of 65.813 ppm, indicating its effectiveness as a free radical scavenger. This study concludes that the ethanol extract of Chinese betel leaves has strong in vitro antioxidant activity based on the DPPH test. These results support the further development of this extract as an adjunct therapy for diabetes mellitus, primarily in reducing oxidative stress. Follow-up suggestions include testing more specific antidiabetic mechanisms (such as α-amylase/α-glucosidase inhibition and in vivo studies), fractionation to isolate active compounds, and toxicity evaluation for development safety.

Comparison of Cellulose Extraction Methods from Lontar (Borassus flabellifer) and Salak (Salacca zalaacca) Fronds

Aisyah Rusdin — 2025-04-27

Palmyra fronds and salak fronds are waste products from the palmyra and salak plants that have not been optimally utilized. However, the high cellulose content in these fronds offers potential applications across various fields. This study aimed to extract and compare cellulose from lontar (Borassus flabellifer) and salak (Salacca zalacca) frond waste using two methods: alkaline sodium hydroxide (NaOH) solvent and nitric acid (HNO₃) hydrolysis. After soaking and heating, the extraction was performed through a bleaching process. The yield results showed that lontar fronds produced the highest yield of 64.22% using the acid hydrolysis method, while salak fronds yielded 46.8%. The cellulose obtained from lontar fronds was gray, and from salak fronds, it was white, indicating differences in purity. After treatment, the disappearance of the carbonyl group (C=O) in the FTIR functional group analysis indicated successful delignification. Common cellulose functional groups such as O-H, C-H, and C-O, as well as β-1,4 glycosidic bands, were detected at wave numbers 895-897 cm⁻¹, indicating that the cellulose structure was well preserved. Cellulose from both lontar and salak fronds has great potential to serve as an environmentally friendly alternative raw material for applications in bioplastics, bioethanol, and other cellulose derivatives.

The Effectiveness of Kahoot Media And e-LKPD In the Application of the Discovery Learning Model for Acid & Base Teaching In Improving Students' Learning Outcomes

Natasya Christie Sihombing — 2025-04-27

This study aims to determine the effectiveness of using Kahoot media and e-LKPD based on the Discovery Learning model in improving student learning outcomes in acid-base solution material at SMA Negeri 10 Medan. The research method used is a quasi-experimental design with a Pretest-Posttest Non-Equivalent Control Group Design. The subjects of the study consisted of four classes: F1, F2, F3, and F5, with each class consisting of 35 students. Class F1 used Kahoot media, F2 used e-LKPD, F3 used a combination of both, and F5 served as the control class. The instrument used was an objective test in the form of 20 multiple-choice questions. The results showed that the average improvement in student learning outcomes was higher in the experimental classes than in the control class. The Independent z-test revealed a significant difference between the experimental and control classes. Thus, the use of Kahoot media and e-LKPD based on discovery learning has proven effective in improving student learning outcomes in acid-base material.

Microemulsion of methanol extract of Tridax procumbens flower and its antibacterial activity against Streptococcus mutans and Enterococcus faecalis

Sri Wijayanti — 2025-05-10

Tridax procumbens (commonly known as Gletang flower) is a medicinal plant recognized for its antibacterial potential and is widely distributed across various habitats such as rice fields, plantations, and roadsides. Phytochemical screening of its methanolic flower extract revealed the presence of secondary metabolites, including alkaloids, flavonoids, steroids, phenols, terpenoids, and tannins, all of which contribute to its biological activities. This study aimed to develop a microemulsion formulation of T. procumbens methanolic extract and to evaluate its antibacterial activity against Streptococcus mutans and Enterococcus faecalis, two major oral pathogenic bacteria. The microemulsion was prepared using the sonication method and characterized by assessing its pH, transmittance, viscosity, physical stability, and particle size using a particle size analyzer. Antibacterial activity was tested using the Kirby-Bauer disk diffusion method. The results indicated that the microemulsion had particle sizes ranging from 300–1000 nm and demonstrated significantly higher antibacterial activity compared to the crude extract, suggesting improved solubility and enhanced bioactivity of the active compounds. This formulation holds promise as a natural antibacterial agent for the prevention of oral infections.

Low-Temperature Synthesis of ZnO Nanoparticles Using a Water-Methanol Solvent for Rhodamine B Photodegradation

Cindy Claudia Christanti — 2025-04-30

Water pollution caused by organic dyes represents a significant environmental issue demanding effective treatment methods. This study aimed to synthesize zinc oxide (ZnO) nanoparticles at a low temperature using a water-methanol mixed solvent and evaluate their photocatalytic potential for the degradation of Rhodamine B (RhB). ZnO nanoparticles were successfully synthesized at a low temperature of 60°C utilizing a mixture of water and methanol as the solvent. Characterization results from X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM) confirmed that the synthesized material consists of wurtzite structure ZnO nanoparticles. Analysis using UV-Vis Diffuse Reflectance Spectroscopy (DRS) showed that the material possesses a band gap energy of 3.16 eV. The as-synthesized ZnO nanoparticles exhibited effective photocatalytic activity for the degradation of the model pollutant RhB under UV light irradiation. A high photodegradation efficiency of 95.58% was achieved within 45 minutes, with a first-order reaction rate constant (k) of 0.0571 min⁻¹. This low-temperature synthesis method based on the water-methanol solvent mixture proved to be a promising and efficient route for producing active ZnO photocatalysts potentially applicable in treating organic dye-contaminated wastewater.

The The Effect of Guided Inquiry Learning Model on Improving Students’ Learning Outcomes in the Periodic Table of Elements Material in Class X at SMA Negeri 1 Sidikalang

Mariana Silitonga — 2025-05-10

This research was conducted at SMA Negeri 1 Sidikalang in the 2024/2025 academic year, involving two classes as research subjects. The experimental group, namely Class X MIPA 5, was given learning using a guided inquiry model, while the control group, namely Class X MIPA 6, was given learning using the traditional method. Each class consists of 36 students. The purpose of this study was to determine the effectiveness of the guided inquiry learning model in improving students' understanding of the material on the periodic table of elements. This study used a pretest-posttest design with non-equivalent groups. Data analysis was carried out quantitatively. The results of the t-test showed that the average increase in student learning outcomes in the experimental class reached 79.0%, while in the control class it was 69.6%. Hypothesis testing using the t-test with degrees of freedom (df) 35 and a significance level of α = 0.05 showed that the calculated t value (th = 23.46) was greater than the t table (t_t = 2.03). This indicates that there is a significant difference between the two groups. Thus, the null hypothesis (H₀) is rejected and the alternative hypothesis (Hₐ) is accepted. Based on the results of the analysis, it can be concluded that the guided inquiry learning model is effective in improving student learning outcomes on the material of the periodic table of elements.

Strategies and Solutions in Overcoming the Challenges of Lipase Utilization in Biodiesel Production: A Review

Cindy Aulia — 2025-05-15

Biodiesel production using lipase as a catalyst offers a more environmentally friendly approach compared to chemical catalysts. However, the application of lipase in industry still faces various challenges, such as high production costs, low enzyme stability, and longer reaction times. To address these constraints, various strategies have been developed. This review not only summarizes these strategies but also highlights recent approaches that are less commonly discussed in the literature, such as the use of non-alcohol routes with methyl acetate and the application of ultrasonic technology to improve conversion efficiency. Additionally, this review provides a fresh perspective by systematically comparing the effectiveness of various lipase immobilization methods and low-cost lipase sources. The uniqueness of this study lies in the comprehensive integration of conventional biocatalysis strategies and emerging innovative approaches. It is hoped that this approach will offer more practical and relevant guidance for the development of enzyme-based biodiesel production technologies, making lipase-based biodiesel production more efficient, economical, and sustainable, while contributing to the reduction of dependency on fossil fuels and the advancement of renewable energy.