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All Journal Jurnal Periodic Jurusan Kimia UNP JURNAL PENDIDIKAN TAMBUSAI Walisongo Journal of Chemistry Eksakta : Berkala Ilmiah Bidang MIPA Pelita Eksakta Hydrogen: Jurnal Kependidikan Kimia CHEDS: Journal of Chemistry, Education, and Science MASALIQ: Jurnal Pendidikan dan Sains Jurnal Sains dan Kesehatan
Riga, Riga
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Religion Agriculture, Biological Sciences & Forestry Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Education Energy Engineering Environmental Science Immunology & microbiology Materials Science & Nanotechnology Mathematics Mechanical Engineering Medicine & Pharmacology Physics Social Sciences Other

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Utilization of Corn Cob Waste into Briquettes as Renewable Fuel in Nagari Lingkuang Aua Bandarajo Syolendra, Dwi Finna; Riga, Riga; Away, Romy Dwipa Yamesa; Saputra, Boni; Mulia, Melindra; Fitri, Bali Yana; Hidayanti, Ermia
Pelita Eksakta Vol 7 No 2 (2024): Pelita Eksakta, Vol. 7, No. 2
Publisher : Fakultas MIPA Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/pelitaeksakta/vol7-iss2/248

Abstract

Pasaman District is the largest corn producer in West Sumatra Province, one of the villages is Lingkuang Aua Bandarajo, where the majority of the population work as corn farmers. This amount is directly proportional to the amount of corn cob waste produced from agricultural activities. Based on the results of observations and interviews with local communities, it is known that the processing of corn cob waste has not been carried out optimally, because people tend to burn the corn cobs, which has an impact on environmental pollution. One solution that can be provided is to hold training on processing corn cob waste into charcoal briquettes. This PKM activity was carried out offline with 3 sessions, namely a session presenting material regarding business opportunities and how to make corn cob briquettes, practice accompanied by a team and independent practice. Through this PKM activity, it is known that there has been an increase in knowledge about corn cob briquettes by the youth of the village of Aua Bandarajo. The corn cob briquettes produced can be a source of renewable fuel and can also improve the economy of local communities.
Pencil Lead Electrode Modified with Gold Thin Layer for Voltammetric Detection of Chromium (VI) Sari, Trisna Kumala; Riga, Riga; Zubir, Moondra
EKSAKTA: Berkala Ilmiah Bidang MIPA Vol. 22 No. 2 (2021): Eksakta : Berkala Ilmiah Bidang MIPA (E-ISSN : 2549-7464)
Publisher : Faculty of Mathematics and Natural Sciences (FMIPA), Universitas Negeri Padang, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (759.742 KB) | DOI: 10.24036/eksakta/vol22-iss2/265

Abstract

Cr(VI) is a toxic, mutagenic, and carcinogenic metal. This heavy metal have effect harmful on organism and the environment. In this study, an electroanalytic approach was improved for detection of the Cr(VI) using a pencil lead electrode modified with gold thin layer by cyclic voltammetry. Gold thin layer was electrodeposited on the pencil lead electrode surface with potential-sweeping technique at scan of potential from 1.2 V to 0 V. Since the Cr(VI) species depends on the pH, effect of supporting electrolytes matrix at various pH were investigated. It was found that Cr(VI) gave a reduction peak with a peak potential of 0.35 V vs Ag/AgCl in cyclic voltammogram with 0.1M HClO4 as supporting electrolyte. The calibration curve for Cr(VI) at gold thin layer modified pencil lead electrode shows linearity in range of 5 µM to 100 µM with a detection limit of 2.3 µM achieved.
Study of The Antibacterial Activity of Endophytic Fungus That Colonize With The Twig of Andrographis paniculata Anshar Al Khairi, Varel; Etika, Sri Benti; Suryelita, Suryelita; Ulfah, Mariam; Riga, Riga
EKSAKTA: Berkala Ilmiah Bidang MIPA Vol. 22 No. 2 (2021): Eksakta : Berkala Ilmiah Bidang MIPA (E-ISSN : 2549-7464)
Publisher : Faculty of Mathematics and Natural Sciences (FMIPA), Universitas Negeri Padang, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1063.338 KB) | DOI: 10.24036/eksakta/vol22-iss2/266

Abstract

Reports of the chemical constituents of Andrographis paniculata showed that this plant produced various secondary metabolites with antibacterial activity. Further exploration of bioactive compounds from A. paniculata can also be conducted by analyzing its endophytic fungi. Isolation of endophytic fungi from the twig of A. paniculata obtained three isolates of endophytic fungi. One of the isolates, RS-2, was fermented on rice media and extracted with ethyl acetate to give the EtOAc extract. The EtOAc extract from fungus RS-2 was analyzed for their antibacterial and phytochemical screening. The results exhibiting the EtOAc extract of fungus RS-2 has activity to inhibite bacterial growth. Overall, the study of the antibacterial activity of endophytic fungus obtained from the twig of A. paniculata was firstly carried out in this study
AKTIVITAS ANTIOKSIDAN DAN ANALISA FITOKIMIA JAMUR ENDOFIT DDH YANG DIISOLASI DARI DAUN DEWA (GYNURA SEGETUM) Dewita, Febby Oktavia; Riga, Riga; Silvani, Mauline Adia; Oktria, Wandi; Agustini, Dewi Meliati
CHEDS: Journal of Chemistry, Education, and Science Vol 8, No 2 (2024)
Publisher : Universitas Islam Sumatera Utara

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30743/cheds.v8i2.9315

Abstract

Dewa dewa (Gynura segetum) merupakan salah satu anggota famili Asteracease yang dilaporkan dapat menghasilkan berbagai senyawa bioaktif dan memiliki aktivitas biologis. Salah satu aktivitas tersebut adalah antioksidan. Sumber alternatif untuk mencari metabolit sekunder dengan aktivitas antioksidan dari dewa dewa adalah jamur endofitnya. Tujuan penelitian ini adalah untuk mengetahui aktivitas antioksidan jamur endofit DDH yang diisolasi dari G. segetum. Hasil uji fitokimia menunjukkan bahwa ekstrak etil asetat jamur endofit DDH mengandung senyawa terpenoid, steroid, fenolik dan alkaloid. Pada penelitian ini aktivitas antioksidan ekstrak etil asetat jamur DDH juga diuji menggunakan metode DPPH.  IC50 ekstrak ini adalah 34,61 ppm yang menunjukkan aktivitas antioksidan kuat.
Pengembangan LKPD Berbasis Problem Based Learning Terintegrasi Etnosains Materi Hidrokarbon Fase F SMA Novita, Rani; Riga, Riga; Hardeli, Hardeli
Jurnal Pendidikan Tambusai Vol. 8 No. 3 (2024)
Publisher : LPPM Universitas Pahlawan Tuanku Tambusai, Riau, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Materi Hidrokarbon merupakan materi yang berisfat abstrak dan dianggap sulit oleh peserta didik. Penelitian ini memiliki tujuan untuk mengembangkan LKPD berbasis problem based learning terintegrasi etnosains materi hidrokarbon fase F SMA dan menentukan validitas dan praktikalitas. Penelitian ini menggunakan jenis penelitian pengembangan Research and Development (R&D) dengan model 4D. Subjek penelitian validitas ini terdiri dari 3 dosen kimia FMIPA UNP dan 2 guru kimia SMA N 1 Tanjung Mutiara. Berpedoman pada data hasil penelitian, menggunakan rumus Aiken’s V didapatkan rata – rata validasi sebesar 0,85 dengan kategori valid. Berdasarkan dari uji praktikalitas oleh 2 guru dan 10 peserta didik diperoleh persentase sebesar 99% dan 94% dengan kategori sangat praktis. Kesimpulan penelitian ini LKPD berbasis problem based learning terintegrasi etnosains fase F SMA telah valid dan sangat praktis.
AKTIVITAS ANTIOKSIDAN JAMUR ENDOFITIK RS-1 YANG DIISOLASI DARI RANTING SAMBILOTO (ANDROGRAPHIS PANICULATA) DENGAN MEDIA PERTUMBUHAN BERAS PUTIH Fadhillah, Namira Putri; Riga, Riga; Fitri, Bali Yana
CHEDS: Journal of Chemistry, Education, and Science Vol 7, No 1 (2023)
Publisher : Universitas Islam Sumatera Utara

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30743/cheds.v7i1.6838

Abstract

Jamur endofitik merupakan mikroorganisme yang hidup di dalam jaringan tumbuhan tanpa merugikan tumbuhan inangnya. Salah satu tumbuhan yang berpotensi sebagai inang pada jamur endofit adalah Andrographis paniculataatau yang dikenal dengan tumbuhan sambiloto. A. paniculata yaitu tumbuhan obat yang memproduksi berbagai metabolit sekunder dan telah dilaporkan memiliki aktivitas antioksidan alami. Penelitian ini bertujuan untuk menguji aktivitas antioksidan dari jamur endofitik RS-1 yang diisolasi dari ranting A. paniculata.Metode dari penelitian ini terdiri dari inokulasi, optimasi, kultivasi dan ekstraksi, uji fitokimia serta uji antioksidan dengan menggunakan metode DPPH dari jamur endofitik pada ranting A. paniculata. Hasil penelitian pada uji fitokimia ekstrak etil asetat jamur endofitik RS-1 mengandung senyawa steroid, fenolik dan alkaloid.Hasil uji aktivitas antioksidan terhadap ekstrak etil asetat jamur endofitik RS-1 menunjukan nilai IC50 yaitu 99,74 ppm. Nilai IC50 menunjukkan bahwa aktivitas antioksidan tergolong kuat.
Studi Molecular Docking dan Farmakoinformatika Senyawa Kurkumin dan Arturmeron pada Tumbuhan Kunyit (Curcuma Longa Linn.) Sebagai Antihipertensi: Molecular Docking and Pharmacoinformatics Study of Curcumin and Arturmeron Compounds in Turmeric Plants (Curcuma Longa Linn.) as Antihypertensive Agustian, Dede Rahman; Syafrizayanti, Syafrizayanti; Alfath, Yuma Nur; Riga, Riga; Kusnanda, Arif Juliari
Jurnal Sains dan Kesehatan Vol. 6 No. 5 (2024): J. Sains Kes.
Publisher : Fakultas Farmasi, Universitas Mulawarman, Samarinda, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25026/jsk.v6i5.2287

Abstract

Content Angiotensin Converting Enzyme (ACE) is an enzyme that is able to convert the peptide angiotensin 1 into angiotensin 2 which plays a role in the process that causes hypertension. Curcumin and artumeron are a group of chemical compounds that are widely contained in the turmeric plant (Curcuma Longa Linn.) which are reported to have the potential to inhibit ACE in vitro. The aim of this research is to predict the binding interactions of the curcumin and artumeron compound groups with the amino acids in ACE and using the native ligand captopril as the standard ligand. The method used was pharmacokinetic screening of active compounds in the curcumin and artumeron groups using ADMET predictions, Lipinski Rule of five and molecular docking simulations with the MOE program. Based on the results of screening and molecular docking simulations, it shows that the curcumin compound can bind to the ACE enzyme with a binding affinity of -6.032 kcal.mol-1 with a binding site with the amino acid Leu 342 better than captopril which has a binding affinity value of 4.427 kcal.mol-1 with binding sites with the amino acids Glu 342, Pro 344 and Thr 345. These results showed the curcumin compound potential used as a candidate for natural ingredients in antihypertensive treatment because according to in silico predictions it has abilities that are not much different from captopril. Keywords:          ACE, antihypertensive, in silico, Curcuma Longa Linn.   Abstrak Angiotensin Converting Enzyme (ACE) merupakan enzim yang mampu merubah peptida angiotensin 1 menjadi angiotensin 2 yang berperan dalam proses penyebab hipertensi. Senyawa kurkumin dan artumeron merupakan golnngan senyawa kimia yang banyak terkandung dalam tumbuhan Kunyit (Curcuma Longa Linn.) dilaporkan mempunyai potensi dalam menghambat ACE secara in vitro. Tujuan penelitian ini adalah untuk prediksi interaksi penambatan golongan senyawa kurkumin dan artumeron  dengan asam-asam amino pada ACE dan menggunakan ligan native kaptopril sebagai ligan standarnya. Metode yang digunakan berupa skrining senyawa aktif golongan kurkumin dan artumeron secara farmakokinetika dengan prediksi ADMET, Lipinski Rule of Five dan simulasi penambatan molekul dengan program MOE. Berdasarkan hasil skrining dan simulasi penambatan molekul menunjukkan bahwa senyawa curcumin dapat berikatan dengan enzim ACE dengan afinitas pengikatan sebesar -6,032 kcal.mol-1 dengan situs pengikatan dengan asam amino Leu 342 lebih baik dibandingkan dengan captopril yang mempunyai nilai afinitas pengikatan sebesar 4,427 kcal.mol-1 dengan situs pengikatan dengan asam amino Glu 342, Pro 344 dan Thr 345. Hasil ini menunjukkan senyawa curcumin  dapat dijadikan sebagai kandidat bahan alami dalam pengobatan antihipertensi karena secara prediksi in silico memiliki kemampuan yang tidak berbeda jauh dengan kaptopril. Kata Kunci:         ACE, antihipertensi, in silico, Curcuma Longa Linn.
Skrining Fitokimia dan Aktivitas Antituberkulosis Lichen Usnea sp.: Phytochemical Screening and Antitubercular Activity of Lichen Usnea sp. Riga, Riga; Agustini, Dewi Meliati; Shidiq, Gin Gin Ash; Ikhsan, Muhammad Habibul
Jurnal Sains dan Kesehatan Vol. 6 No. 5 (2024): J. Sains Kes.
Publisher : Fakultas Farmasi, Universitas Mulawarman, Samarinda, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25026/jsk.v6i5.2381

Abstract

This research aims to identify fractions inhibiting the growth of M. tuberculosis. The sample in this study was Usnea sp. dissolved in methanol followed by extraction with EtOAc. Antituberculosis testing was carried out using the Microscopic Observation Drug Susceptibility (MODS) method on both extracts (methanol and ethyl acetate) with media as negative control and media and Polymyxin, Amphotericin B, Nalidixic acid, Trimethoprim and Azlocillin (PANTA) as positive control. Observations of them were carried out until the 14th day using a microscope. The observation results showed that the EtOAc extract had a strong minimum killing power against M. tuberculosis isolate H37Rv, while the methanol extract showed a moderate minimum killing power against M. tuberculosis isolate H37Rv at a concentration of 250 ppm. Interestingly, the antitubercular activity using MODS method from Usnea sp. extract. Was firstly studied in this research. Keywords:          Lichen, M. Tuberculosis, MODS, Usnea sp.   Abstrak Tujuan studi ini yaitu untuk mengidentifasi fraksi yang dapat menginhibisi pertumbuhan bakteri M. tuberculosis. Sampel yang diujikan adalah ekstrak pekat Lichen Usnea sp. yang dilarutkan dengan metanol yang selanjutnya diekstraksi dengan etil asetat. Aktivitas antituberkulosis ditentukan dengan metode Microscpy Observation Drug Susceptibility (MODS) terhadap kedua ekstrak (metanol dan etil asetat). Media kosong digunakan sebagai kontrol negatif dan kontrol positif berupa media dan Polymyxin, Amphotericin B, Nalidixic acid, Trimethoprim and Azlocillin (PANTA). Isolat bakteri yang digunakan adalah M. tuberculosis isolat H37Rv. Pengamatan dilakukan sampai hari ke-14 menggunakan mikroskop. Hasil pengamatan menunjukkan bahwa ekstrak etil asetat memiliki daya bunuh minimum yang kuat terhadap M. tuberculosis isolat H37Rv, sementara ekstrak metanol menunjukkan daya bunuh minimum yang sedang terhadap M. tuberculosis isolat H37Rv pada konsentrasi 250 ppm. Menariknya, penelitian uji aktivitas antituberkular menggunakan metode MODS dari ekstrak Usnea sp. pertama kali dilakukan pada penelitian ini. Kata Kunci:         Lichen, M. Tuberculosis, MODS, Usnea sp.
Implementation of Sekolah Penggerak Programme to Address Chemistry Teachers Competency on Design PjBL-based Digital Teaching Materials in Padang Suryani, Okta; Sari, Trisna Kumala; Riga, Riga; Mawardi, Mawardi; Putra, Ahadul
Hydrogen: Jurnal Kependidikan Kimia Vol. 12 No. 5 (2024): October 2024
Publisher : Universitas Pendidikan Mandalika

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33394/hjkk.v12i5.12952

Abstract

Teaching materials for Sekolah Penggerak should be prepared based on a creative thinking learning model such as project-based learning (PjBL). However, based on the needs and situation of teachers towards the implementation of PjBL-based learning, implementation of PjBL in learning is still low, since the teachers in Padang need the advance training of preparation in PjBL learning material. The Community service activities have been carried out to provide experienced chemistry teachers in developing teaching materials based on Project-Based Learning. The implementation methods carried out in this activity are: (1) Analyzing the needs and situation of teachers towards the implementation of PjBL-based learning through questionnaires distributed, (2) Submission of material to service participants related to the PjBL learning model and syntax in this learning model explained by the speaker, then (3) Teachers are given the task of compiling and designing chemistry LKPDs using the PjBL model, (4) Teachers will present the results of the LKPD design compiled, and (5) evaluation of activities. The results of the service activities carried out can provide experience and understanding for chemistry teachers in Padang city regarding the PjBL learning model. Participants who attended this service activity could prepare chemistry teaching materials using the PjBL model so that teachers could be more innovative and creative. This activity service can provide motivation for teachers to prepare teaching materials in accordance with the demands of the Kurikulum Merdeka, especially in the implementation of project-based learning.
The Chemistry Teacher Activities on The Training of Project Based Learning Teaching Materials Digitalisation Suryani, Okta; Sari, Trisna Kumala; Riga, Riga; Mawardi, Mawardi; Yuhelman, Nofri; Nasra, Edi; Velly, Aglin; Rahmad, Nafisah Yulia
Hydrogen: Jurnal Kependidikan Kimia Vol. 12 No. 6 (2024): December 2024
Publisher : Universitas Pendidikan Mandalika

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33394/hjkk.v12i6.13495

Abstract

This activity is the second year of community service which is a continuation of training activities and making digital teaching materials to support project-based learning (PjBL) in sekolah penggerak for chemistry teachers in Padang city. This second year of community service activities has the theme of training to digitise project-based learning teaching materials developed at the Chemistry Musyawarah Guru Mata Pelajaran (MGMP) in Padang city. This activity aims to provide direction to Padang city chemistry teachers in implementing digital teaching materials. This community service was carried out in the lecture building of FMIPA Universitas Negeri Padang on 9 August, 16 August, and 23 August 2024. The implementation methods carried out in this community service activity are: (1) conducting a needs analysis, knowing the situation of teachers towards the implementation of PjBL-based learning through questionnaires distributed, (2) delivering material to community service participants related to PjBL and an overview of teaching materials that have been designed using the PjBL learning model explained by the speaker, then (3) delivery of materials and discussions related to differentiated learning with the PJBl learning model, and (4) delivering material related to the digitalisation of project-based teaching materials or PjBL using liveworksheet. The results of the service activities carried out can provide motivation, provide experience, and understanding for Padang city chemistry teachers regarding the digitalisation of project-based learning teaching materials so that chemistry teachers in Padang city can prepare digital chemistry teaching materials, especially with liveworksheets using the PjBL model that can assist learning activities so that learning can run effectively and efficiently in accordance with the demands of the curriculum and the times.
Co-Authors Agustian, Dede Rahman Agustini, Dewi Meliati Ahadul Putra Aini, Syamsi Alfath, Yuma Nur Anshar Al Khairi, Varel Baehaqi Boni Saputra Budhi Oktavia Dewita, Febby Oktavia Dwi Finna Syolendra Edi Nasra Fadhillah, Namira Putri Fitri, Bali Yana Fitria, Fadhila Hardeli Hardeli Hary Sanjaya Hayuni, Sri Hidayanti, Ermia Ikhsan, Muhammad Habibul Iryani Iryani Jayawarsa, A.A. Ketut Kusnanda, Arif Juliari Mulia, Melindra Nizar, Umar Kalmar Nofri Yuhelman Novita, Rani Oktria, Wandi Pebriani Pebriani Pramesti, Radia Sagita Putra, Ahadul Putra, Ananda Putri, Sinta Eka Rahmad, Nafisah Yulia Romy Dwipa Yamesa Away Sari, Trisna Kumala Serli, Salsabilla Putri Shidiq, Gin Gin Ash Silvani, Mauline Adia Sri Benti Etika Suryani, Okta Suryelita, Suryelita Syafrizayanti, Syafrizayanti Ulfah, Mariam Velly, Aglin Wulandari, Yolanda Zahran, Jihan Fadhilah Zubir, Moondra