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All Journal CHEMISTRY PROGRESS Indonesian Journal of Chemistry The Studies of Social Sciences Jurnal Ilmiah Sains
Koleangan, Harry Steven Julius
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Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Decision Sciences, Operations Research & Management Economics, Econometrics & Finance Environmental Science Mathematics Physics Social Sciences

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Aktivitas Penghambatan Enzim ꭤ-Amilase oleh Ekstrak Etanol Hasil Soxhletasi dan Refluks Daun Manggis (Garcinia mangostana L.) Pettanaga, Putri Firania; Katja, Dewa Gede; Koleangan, Harry Steven Julius
CHEMISTRY PROGRESS Vol. 17 No. 2 (2024)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/cp.17.2.2024.56254

Abstract

ABSTRAK Penelitian ini bertujuan untuk menentukan kandungan senyawa fenolik, flavonoid, dan tanin terkondensasi dalam ekstrak etanol yang diperoleh melalui soxhletasi dan refluks daun manggis dan untuk menentukan efektivitasnya terhadap penghambatan enzim ꭤ-amilase. Penelitian dikerjakan melalui tahapan-tahapan preparasi, ekstraksi, penentuan kandungan total fenolik, flavonoid, dan tanin terkondensasi, serta penentuan aktivitas penghambatan enzim ꭤ-amilase. Rendemen tertinggi diperoleh pada ekstrak etanol hasil refluks selama 4 jam (R4) (19,88%) dan terendah diperoleh pada ekstrak etanol hasil soxhletasi selamas 2 jam (S2) (7,97%). Kandungan total fenolik dan flavonoid tertinggi ditemukan pada ekstrak etanol hasil soxhletasi selama 8 jam (S8) (226,73 µg/mL dan 266,76 µg/mL). Kandungan tanin terkondensasi tertinggi diperoleh pada ekstrak etanol hasil soxhletasi selama 4 jam (S4) (24,36 µg/mL). Aktivitas penghambatan enzim ꭤ-amilase tertinggi ditunjukkan oleh ekstrak etanol hasil soxhletasi selama 4 jam (S4) 750 µg/mL (92,95%). Dapat disimpulkan bahwa ekstrak etanol daun manggis yang diperoleh melali proses soxhletasi lebih efektif dalam menghambat enzim ꭤ-amilase dibandingkan dengan yang diperoleh melalui proses refluks.   ABSTRACT This research was aimed to determine the content of phenolic compounds, flavonoids, and condensed tannins in ethanol extracts obtained through soxhletation and reflux of mangosteen leaves, and to determine their effectiveness in inhibiting the α-amylase enzyme. The research was conducted through the stages of preparation, extraction, determination of total phenolic, flavonoid, and condensed tannin content, as well as determination of α-amylase enzyme inhibition activity. The highest yield was obtained from the ethanol extract produced by reflux for 4 hours (R4) (19.88%) and the lowest was obtained from the ethanol extract produced by Soxhletation for 2 hours (S2) (7.97%). The highest total phenolic and flavonoid content was found in the ethanol extract produced by Soxhletation for 8 hours (S8) (226.73 µg/mL and 266.76 µg/mL). The highest condensed tannin content was obtained in the ethanol extract produced by Soxhletation for 4 hours (S4) (24.36 µg/mL). The highest α-amylase enzyme inhibition activity was shown by the ethanol extract produced by Soxhletation for 4 hours (S4) 750 µg/mL (92.95%). It can be concluded that the ethanol extract of mangosteen leaves obtained through the Soxhletation process is more effective in inhibiting the α-amylase enzyme compared to that obtained through the reflux process.
Pelatihan Pembuatan Obat Luka dari Limbah Daun Pala Bagi Ibu-ibu PKK Desa Pales, Kecamatan Likupang Barat, Kabupaten Minahasa Utara Katja, Dewa Gede; Koleangan, Harry Steven Julius; Pollo, Hard Napoleon; Sinaga, Jonathan Cavin Ezra
The Studies of Social Sciences Vol. 6 No. 2 (2024): The Studies of Social Sciences
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35801/tsss.v6i2.58432

Abstract

Kegiatan Program Kemitraan Masyarakat (PKM) telah dilaksanakan dengan judul Pelatihan Pembuatan Obat Luka Bagi Ibu-ibu PKK Desa Palaes, Kecamatan Likupang Barat, Kabupaten Minahasa Utara. Kegiatan ini diawali dengan produksi minyak atsiri dari limbah daun pala, serta dilanjutkan dengan perumusan kegiatan. Ibu-ibu PKK desa Palaes memiliki potensi untuk menjadi kader pembawa informasi kepada masyarakat sekitar tentang manfaat limbah daun pala yang dapat dijadikan plester luka. Kegiatan ini bertujuan untuk memberikan pengetahuan dan ketrampilan bagi masyrakat dalam memanfaatkan limbah daun pala. Metode yang digunakan adalah pelatihan tentang pembuatan plester obat dari limbah daun pala serta evaluasi kepada peserta. Dari kegiatan ini, Ibu-ibu PKK telah mampu memahami dan mengetahui cara produksi minyak atrisi dari limbah daun pala serta dapat membuat plester luka.
Magnetically Active GO-Fe3O4 Nanocomposite for Enhanced Rhodamine B Removal Efficiency Souhuat, Alexander; Aritonang, Henry Fonda; Koleangan, Harry Steven Julius
Indonesian Journal of Chemistry Vol 24, No 6 (2024)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.96383

Abstract

According to the World Bank study, approximately 17–20% of water contamination is attributed to the textile industry. The quantity of waste produced increases as a result of increased productivity. Textile wastewater contains dyes such as rhodamine B (RhB), which are hazardous and challenging to remove using standard methods. Adsorption utilizing nano-adsorbents has been widely researched and developed to remove dyes from the environment because of its numerous advantages. Graphene oxide-magnetite (GO-Fe3O4) has been extensively explored as an adsorbent due to its large surface area, strong bonding, and ease of separation from water. In this study, GO-Fe3O4 was synthesized by combining GO from coconut shell with Fe3O4 from iron sand as an absorbent to lower the amount of RhB. Various analytical techniques, including XRD, SEM-EDS, TEM, FTIR, and UV-vis, were employed to examine the properties of the composites. The GO-Fe3O4 exhibited a maximum adsorption capacity of 34.590 mg/g under specific conditions, i.e., 0.5 g adsorbent dosage, pH 4, and a 2 h contact time. The adsorption followed the pseudo-second-order kinetics model with 0.00016 mg/g min adsorption rate while the adsorption isotherm followed the Langmuir model where adsorbent surfaces are spread homogeneously by forming a monolayer.
Antioxidant, Antibacterial, Cytotoxic, and Anticancer Potential of Belulang Grass (Eleusine indica) Kamu, Vanda Selvana; Runtuwene, Max Revolta John; Merentek, Jetlee; Koleangan, Harry Steven Julius; Kumaunang, Maureen
Jurnal Ilmiah Sains Volume 25 Issue 1, April 2025
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v25i1.58431

Abstract

A study was conducted to determine the antioxidant, antibacterial, cytotoxic, and anticancer activities of the belulang grass plant (Eleusine indica). Antioxidant activity was assessed using the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity method. Antibacterial activity was determined using the disk diffusion method, cytotoxicity was determined using the Brine Shrimp Lethality Test (BSLT), and anticancer activity was evaluated using the MTS assay. The results showed that the antioxidant activity of the extracts and solvent fractions of Eleusine indica had the highest average value for the n-hexane fraction (FNH) at 35.0%, ethyl acetate fraction (FEA) at 56.4%, aqueous fraction (FA) at 30.3%, and methanol extract (EM) at 32.5%. Among these, the highest value was obtained in FEA, while the lowest was obtained in FA. Based on the cytotoxicity test with the BSLT method, the ethyl acetate fraction had an LC50 value of 7.384 ppm, categorizing it as highly toxic. However, in cytotoxicity testing with HeLa cells, the IC50 value for the ethyl acetate fraction was 223.70 ppm, indicating that the ethyl acetate fraction was less active against HeLa cervical cancer cells. Keywords: Eleusine indica; belulang grass; cytotoxic; HeLa cells
Co-Authors Dewa Gede Katja Henry Aritonang Maureen Kumaunang Max Revolta John Runtuwene Merentek, Jetlee Pettanaga, Putri Firania Pollo, Hard Napoleon Sinaga, Jonathan Cavin Ezra Souhuat, Alexander Vanda Selvana Kamu