Universitas Negeri Manado, Jurusan Kimia: Open Journal Systems
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Isolation and Characterization of Dryland Microfungi From Northern Insana as Potential Sources of Antibacterial Agents
Get PDFMicrofungi are one of the most extensively studied groups of microorganisms due to their remarkable ability to produce a diverse range of unique bioactive compounds. This study aimed to explore and characterize microfungi isolated from the drylands of North Insana as potential sources of sustainable antibacterial agents. The research methods included the isolation of microfungi, morphological identification, and evaluation of antibacterial activity using the disc diffusion method. Based on morphological characterization, microfungi isolated from the North Insana dry soil showed similarities to three genera, namely Mucor, Penicillium/Aspergillus, and Aspergillus. Antibacterial assays revealed that all three isolates exhibited varying degrees of activity, ranging from moderate to strong, against Staphylococcus aureus. Isolate 1 produced an inhibition zone of 7.6 ± 0.20 mm (moderate activity), isolate 2 produced 10.17 ± 0.06 mm (strong activity), and isolate 3 produced 10.77 ± 0.06 mm (strong activity). According to the Tukey test (p < 0.05), isolate 3 showed no significant difference from the standard antibiotic chloramphenicol (11.23 ± 0.15 mm), indicating a comparable antibacterial effectiveness. These results suggest that dryland-endemic microfungi possess adaptive biosynthetic capacities, enabling them to produce antibacterial secondary metabolites in response to extreme environmental stress. This potential reinforces the role of dryland microfungi as promising new sources of natural antibacterial compounds for sustainable biotechnological and health application
Literature Review : Penerapan Metode Eksperimen Berbasis Lingkungan untuk Meningkatkan Hasil Belajar Kimia Peserta Didik SMA
Get PDFPenelitian ini bertujuan untuk mengevaluasi sejumlah artikel ilmiah yang berkaitan dengan penggunaan metode eksperimen berbasis lingkungan dalam upaya meningkatkan pencapaian belajar kimia peserta didik di tingkat sekolah menengah atas. Metode ini menggabungkan prinsip-prinsip pembelajaran kimia dengan eksperimen atau praktikum yang memanfaatkan bahan alami dan lingkungan sekitar. Berbagai sumber akademis dieksplorasi untuk meninjau dampak positif metode ini terhadap pemahaman konsep, keterampilan praktis, dan minat belajar peserta didik dalam kimia. Hasil kajian menunjukkan bahwa penggunaan metode eksperimen berbasis lingkungan masih memerlukan evaluasi lebih lanjut untuk memastikan efektivitasnya. Temuan juga menunjukkan bahwa metode ini mendorong sikap peduli lingkungan dan penerapan konsep kimia dalam konteks dunia nyata. Implikasi dari tinjauan literatur ini adalah pengembangan strategi pembelajaran yang lebih berorientasi pada lingkungan dan kontekstual untuk meningkatkan hasil belajar kimia peserta didik di SMA
Physicochemical Properties of Rice Fortified with Payangka Fish Protein Hydrolysate
Get PDFRice is an energy source that is high in carbohydrates and contributes to providing the largest percentage of calories, but rice has a low protein, vitamin and mineral content, so it needs to be fortified to increase the nutritional content of rice, especially protein. This research aims to characterize rice that has been fortified with protein hydrolyzate. Synthesis of Payangka fish protein hydrolyzate was carried out using papain enzyme with concentrations of 2,4 and 6% with an incubation time of 2 hours. The best fortification of rice is done by soaking the rice for 4 hours, then drying it again for 14 hours at a temperature of 50oC. The research results show that Payangka fish hydrolyzate can be obtained through hydrolysis of Payangka fish meat using the Papain enzyme with a concentration of 2-6%. The highest protein content of protein hydrolyzate was obtained when using a Papain enzyme concentration of 6% with a protein content of 3.61%. Fortification of rice with Payangka fish protein hydrolyzate can increase rice protein content, namely from 9.43% (before fortification) to 10.38% (after fortification using protein hydrolyzate with a concentration of 30%
The Adsorption of Heavy Metal Mercury (Hg) Using Meranti Wood as Activated Carbon
No full textThe objective of this research is to assess the adsorption capacity of activated carbon derived from meranti wood (Shore spp) for mercury (Hg) removal from liquid waste. To establish the relationship between concentration and absorbance, the method employed involves calibrating mercury concentration using calibration curves. Additionally, the effects of pH and exposure time on adsorption capacity were examined. The results indicate that activated carbon from meranti wood can significantly adsorb mercury, achieving an efficiency level of 97.610% at pH 3, with adsorption stability reached within 80 minutes at an adsorption rate of 94.30%. The conclusions drawn from this study suggest that activated carbon from meranti wood is a sustainable and effective solution for addressing mercury contamination in wastewater. It also highlights the importance of regulating pH and exposure time. This research contributes significantly to the development of environmentally friendly methods for water purification
Physical and Chemical Parameters of Water in Cigunung River, Sukabumi, Indonesia
Get PDFPenelitian ini bertujuan untuk mengetahui kualitas air Sungai Cigunung, Sukabumi yang meliputi TDS, TSS, pH, DO, BOD dan COD. Pengambilan sampel dilakukan di tiga titik sepanjang Sungai Cigunung, yaitu stasiun 1 (hulu), stasiun 2 (tengah) dan stasiun 3 (hilir). Hasil penelitian menunjukkan bahwa suhu pada ketiga stasiun berkisar antara 23,21°C - 26,62°C; TDS berkisar antara 0,16 mg/l - 0,75 mg/l, pH berkisar antara 7,73 - 7,78; DO berkisar antara 6,4 mg/l - 71 mg/l; nilai TSS pada stasiun 1 dan 2 masing-masing sebesar 0,91 mg/l, dan 0,08 mg/l pada stasiun 3; serta nilai BOD pada stasiun 2 dan 3 masing-masing sebesar 4 mg/l dan 3 mg/l. Berdasarkan hasil analisis parameter air dengan menggunakan baku mutu air PP No. 22 Tahun 2020 diketahui bahwa bagian hulu sungai Cigunung Sukabumi tergolong kelas I yang dapat dimanfaatkan untuk air minum sedangkan bagian tengah dan hilir tergolong kelas II yang dapat dimanfaatkan untuk irigasi pertanian
Penerapan Model Project Based Learning Pada Materi Ikatan Kimia Untuk Meningkatkan Hasil Belajar Siswa Kelas X di SMA Negeri 1 Likupang
Get PDFThis research is classroom action research which aims to improve student learning outcomes in chemical bonding material through the application of the project based learning model. There are several things that underlie this research, namely the low interest in student learning in chemistry subjects which then makes student learning outcomes unsatisfactory. The research carried out is classroom action research (PTK) which takes place in two cycles, in cycle I it is held three meetings and in cycle II it is held two meetings. Each cycle in this research consists of a planning stage. implementation, observation and reflexology Data collection techniques were carried out using observation sheets and written tests. Based on the research results, it was found that the project based learning model could improve student learning outcomes. This can be seen from the percentage of student learning outcomes which increased from 60% in cycle I which then increased to 96% in cycle II.Penelitian ini merupakan penelitian tindakan kelas yang bertujuan untuk meningkatkan hasil belajar siswa pada materi ikatan kimia melalui penerapan model project based learning. Terdapat beberapa hal yang mendasari penelitian ini adalah rendahnya minat belajar siswa pada mata pelajaran kimia yang kemudian membuat hasil belajar siswa kurang memuaskan. Penelitian yang dilakukan merupakan penelitian tindakan kelas (PTK) yang berlangsung dalam dua siklus, pada siklus I dilaksanakan tiga kali pertemuan dan disiklus II dilaksanakan dua kali pertemuan. Masing-masing siklus pada penelitian ini terdiri dari: tahap perencanaan, pelaksanaan, observasi, dan refleksi. Teknik pengumpulan data dilakukan dengan menggunakan lembar observasi dan tes tertulis. Berdasarkan hasil penelitian yang diperoleh bahwa model pembelajaran project based learning dapat meningkatkan hasil belajar siswa. Hal tersebut dapat dilihat dari presentase hasil belajar siswa yang meningkat dari 60% pada siklus I yang selanjutnya meningkat menjadi 96% pada siklus II
Quantitative Determination of Ascorbic Acid Content in Two Varieties of Bird’s Eye Chili (Capsicum frutescens L.) using UV-Vis Spectrophotometry
Get PDFThis study quantified and compared the ascorbic acid content in green and red bird's eye chili (Capsicum frutescens) using UV-Vis spectrophotometry. The method was optimized by determining the maximum wavelength of ascorbic acid in an acid-stabilized solution, found to be 231 nm. A calibration curve was constructed with standard solutions (25-100 ppm), yielding a linear equation y = 0.0514x + 0.6032 (R² = 0.9361). Sample extracts were prepared and analysed in triplicate at this wavelength. The results demonstrated a significant difference in ascorbic acid concentration between the two varieties. The red chili exhibited a higher concentration of 34.39 ppm in the measured solution, corresponding to 0.90% (b/b) of the fresh weight. In contrast, the green chili contained 23.95 ppm (0.60% b/b). This indicates a 50% higher ascorbic acid content in the mature red fruit. The study concludes that ripening significantly enhances the vitamin C content in bird's eye chili, and the red variety is a nutritionally superior source. The validated method proved effective for the quantitative analysis of ascorbic acid in complex food matrices
Penerapan Project Based Learning Pada Materi Asam Basa Untuk Meningkatkan Hasil Belajar Siswa Di SMA Negeri I Tagulandang
Get PDFThis research was conducted with the aim of determining the effect of implementing the PjBL model in improving the learning outcomes of class XII A students at SMA Negeri 1 Tagulandang. This research was carried out in two learning cycles and the learning stages consisted of determining basic questions, preparing a project design, creating an activity schedule, monitoring the distribution of student performance and evaluating experience. The research objects were class XII A students of SMA Negeri 1 Tagulandang for the odd semester 2024/2025 academic year, totaling 32 students. Data collection techniques include observation, learning results tests and documentation. The data analysis technique includes test results data. The results show that the level of student learning completion has increased. In cycle I, the percentage of completeness was obtained, namely 56.20% with the highest score of 88. Meanwhile, in cycle II, the percentage of completeness was obtained, namely 90.62%, with the highest score being 93. Based on the research results, the application of the PjBL model improved student learning outcomes.Penelitian ini dilakukan bertujuan untuk mengetahui pengaruh penerapan model PjBL dalam meningkatkan hasil belajar siswa kelas XII A di SMA Negeri 1 Tagulandang.
Penelitian ini dilakukan dalam dua siklus pembelajaran dan tahapan pembelajarannya terdiri dari menentukan pertanyaan mendasar, Menyusun desain proyek, membuat jadwal aktivitas, melakukan monitor pada pembagian kinerja peserta didik serta mengevaluasi pengalaman. Objek penelitian adalah siswa kelas XII A SMA Negeri 1 Tagulandang tahun ajaran semester ganjil 2024/2025 yang berjumlah 32 peserta didik. Teknik pengumpulan data meliputi observasi, tes hasil belajar dan dokumentasi. Teknik analisis data meliputi data hasil tes. Daam hasil menunjukan bahwa tingkat ketuntasan belajar siswa mengalami kenaikan. Pada siklus I diperoleh presentase ketuntasan yaitu 56,20% dengan nilai tertinggi 88. Sedangkan, pada siklus II ini di peroleh presentase ketuntasan yaitu 90,62% dengan nilai tertinggi yaitu 93. Berdasarkan hasil penelitian, penerapan model PjBL meningkatkan hasil belajar siswa
Molecular Docking and Molecular Dynamics Analysis of Phytochemical Compounds from Nutmeg Fruit (Myristica fragrans Houtt.) on Androgen Receptor (4K7A) as Anti-Alopecia Therapy
Get PDFAndrogenetic alopecia (AGA) represents the most prevalent hair loss form, necessitating natural treatment alternatives. This study investigated nutmeg (Myristica fragrans Houtt.) phytochemicals as anti-alopecia agents through molecular docking and dynamics simulations. Thirty-four compounds, including native ligands (minoxidil, finasteride) and 32 nutmeg-derived compounds, were evaluated against androgen receptor (PDB: 4K7A) using AutoDock4.0 and GROMACS 2024.2. Molecular docking validation achieved successful minoxidil redocking with 2.25 Å RMSD, confirming method reliability. Geranylgeraniol (ID: 33) demonstrated optimal results with -7.00 kcal/mol binding energy, nearly equivalent to finasteride (-7.19 kcal/mol) and superior to minoxidil (-4.85 kcal/mol). Geranylgeraniol formed strong hydrogen bonds with GLU793 at 1.77 Å distance, with nearby residues LEU862, TYR857, ARG854, LYS861, and LEU797. Twenty-five nanosecond molecular dynamics revealed stable complex formation with 0.23-0.25 nm RMSD values, indicating acceptable binding stability. RMSF analysis showed geranylgeraniol induced higher structural flexibility in specific regions, potentially enhancing biological activity. SASA analysis demonstrated lower surface area values (112.5 nm²), indicating improved stability versus minoxidil. These findings suggest geranylgeraniol possesses significant anti-alopecia potential with comparable finasteride efficacy and superior minoxidil performance
Analysis of Lipid Yield from Chaetoceros calcitrans Microalgae Extract Using Gas Chromatography
Get PDFRenewable energy (RE) is a solution to the threat of the upcoming energy crisis. The increasingly massive energy transition is expected to significantly reduce the use of fossil fuels. Microalgae are one of the potential sources of RE for bioenergy (biodiesel) production due to their lipid content. This research was conducted to determine the percentage of lipid components; free fatty acids (FFA), monoglycerides (MAG), diglycerides (DAG), and triglycerides (TAG) in Chaetoceros calcitrans microalgae and to compare lipid yields using two extraction methods: Bligh-Dyer (wet samples) and Soxhlet extraction (dry samples).The results for C. calcitrans extracted using the Bligh-Dyer method showed that the percentage of lipid components (FFA, MAG, DAG, and TAG) ranged from 5.44% to 17.10%, with a total of 47.92%, and the lipid yield from 6 g of wet sample was 5.07%.Meanwhile, for the C. calcitrans extract using Soxhlet method, it was found that the percentage of lipid components (FFA, MAG, DAG and TAG) ranged from 6.79 to 18.01% with a total of 63.08% and the lipid yield from 20 g of dry samples was 0. 44%