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Jurnal Riset Kimia
Published by Universitas Andalas
ISSN : 1978628X     EISSN : 24768960     DOI : -
Core Subject : Science,
Chemistry
Arjuna Subject : -
Articles 551 Documents
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Karakterisasi Selulosa dan Selulosa Asetat dari Limbah Cangkang Biji Pala (Myristica Fragransi) Aceh Selatan Bhayu Gita Bhernama; Nurhayati; Surya Adi Saputra; Jihan Amalia
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.579

Abstract

Nutmeg seed shell waste contains 21.34% cellulose, 12.93% lignin, 53.67% crude fiber, 6.16% ash, 0.11% phenol, and 0.38% carbonyl. The content of cellulose and lignin in the nutmeg shell waste is quite large, so it can be used as something of value. Cellulose can be synthesized into cellulose acetate. The use of cellulose acetate is very diverse, such as in the film industry, biodegradable plastics, paper coatings, metals, and glass, as an adhesive for topographic films as the main raw material in membrane synthesis processes. Therefore, it is necessary to characterize cellulose and cellulose acetate from nutmeg shell waste (Myristica fragrance) in South Aceh. The method used is in the form of cellulose isolation using the soxhletation process, then bleaching and hydrolysis processes are carried out, then it is synthesized into cellulose acetate. Characterization of cellulose by determining % yield, cellulose content, ash content, moisture content, FTIR, XRD. Characterization of cellulose acetate by determining the acetyl content and FTIR. The characterization results obtained ash content of 3.04%, moisture content of 15.55%, yield of 35.36% and 5.29% cellulose content. XRD characterization obtained a diffractogram peak at an angle of 2θ = 22.2111o, a crystallinity of 96% and a crystal size of 0.5292 nm. Characterization of the functional groups of cellulose in the form of stretching O-H, C-H and C-O groups which are at wave numbers 3331.04 cm-1, 2871.29 cm-1 and 1024.96 cm-1. Functional groups of cellulose acetate in the form of O-H, C=O, acetyl C-O, bent C-H and C-O groups are at wave numbers 3348.82 cm-1, 1719.61 cm-1, 1227.23 cm-1, 1369.50 cm-1 and 1028.62. The acetyl content is 39.18% and the degree of substitution is 2.65%.
Komponen Kimia Minyak Atsiri yang Diisolasi dari Daun Tanaman Pucuk Merah (Syzygium myrtifolium Walp.) dan Potensi Antibakteri serta Toksisitasnya Suryati; Thaharah Alifa Aziz Yenuuar; Shafinna Hana Fadhia; Rahmi Vika Ulia; Miftahul Melsya Salsabilla; Bustanul Arifin
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.583

Abstract

Pucuk merah (Syzygium myrtifolium Walp.) is an ornamental plant from the Myrtaceae family. Several phytochemical tests from previous researchers reported that pucuk merah contains secondary metabolites that have benefits such as antioxidants, antibacterials, and anti-cancer. In addition, the distinctive aroma produced from pucuk merah  leaves indicates the presence of essential oils whose bioactivity can be studied. Still, there has been no report on this plant's chemical components or bioactivity. Therefore, this study aims to determine the content of chemical components of pucuk merah  essential oil and their bioactivity as antibacterial and toxicity. The isolation of essential oils was carried out by the hydro distillation method. The chemical components of essential oils were analyzed using the Gas Chromatography-Mass Spectrometry (GC-MS) method. GC-MS results showed the presence of 42 compounds with four main compounds, namely caryophyllene (23.45%), 3-carene (15.67%), α-terpineol (10.74%), and α-pinene (5.98%) ). Antibacterial test of pucuk merah  essential oil using the disc diffusion method showed strong activity against Staphylococcus aureus and Escherichia coli with inhibition zones of 16.15 ± 2.03 and 16.13 ± 1.74 mm at 100% concentration. The results of the toxicity test of pucuk merah  essential oil using the BSLT (Brine Shrimp Lethality Test) method on Artemia salina Leach shrimp larvae showed strong toxic properties with an LC50 value of 3.99 µg/mL.
Pengembangan Sensor Kimia Berbasis Kertas Untuk Penetapan Kadar Kafein Sampel Kopi Mochammad Amrun Hidayat; Noviani Tri Wahyuning; Indah Yulia Ningsih; Bambang Kuswandi
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.589

Abstract

The caffeine chemical sensor was developed by co-immobilizing sodium periodate (NaIO4), 3-methyl-2-benzothiazolinone hydrazone (MBTH), and acetic acid (CH3COOH) onto paper by using an adsorption technique. The addition of caffeine solution could change the color of the sensor from white to pale blue which can be then captured by using a flatbed scanner and quantified by the ImageJ program, known as a scanometric technique. Method validation such as linearity, LOD, LOQ, precision, and accuracy of the sensor was done by using caffeine standards. The result of caffeine analysis using the developed chemical sensor-scanometric method agreed with that of the spectrophotometric method, suggesting that the developed sensor with scanometric technique can be used as an alternative method for caffeine assay in coffee samples.
Potensi Daun Sirsak (Annona Muricata L.) sebagai Kandidat Fungisida Nabati Penghambat Pertumbuhan Cendawan Patogen Colletotrichum Gloeosporioides Syayyidah Fatimatuz Zahro; Lailatul Restuning Putri Istiqomah; Galuh Citra Cahya Rohmana; Denise Ayu Yustikaningrum; Christyfani Sindhuwati
Jurnal Riset Kimia Vol. 14 No. 1 (2023): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i1.590

Abstract

The attack of the Colletotrichum gloeosporioides fungus causes losses to farmers. The prolonged use of synthetic fungicides to treat this fungus harms the environment and consumers. Soursop leaves (Annona muricata L.) contain antioxidant compounds that act as antifeedants, contact poisons, and stomach poisons for plant pests and can potentially become a vegetable fungicide as a growth inhibitor for Colletotrichum gloeosporioides in postharvest horticulture. This study used a multilevel extraction method with solvents of n-hexane, ethyl acetate, and 95% ethanol. Tests for the content of secondary metabolites of soursop leaf extract in the form of alkaloids, flavonoids, saponins, and tannins were carried out qualitatively and quantitatively using a UV-Vis Shimadzu 1800 spectrophotometer. The inhibition test of the extract against the fungus Colletotrichum gloeosporioides was carried out using disc paper soaked with soursop leaf extract for a certain time. The qualitative test results of soursop leaf extract showed that it contained alkaloids, flavonoids, saponins, and tannins. The fungal inhibition zone test showed the most optimal results on soursop leaf extract with a long extraction time of 144 hours and a content of 50%, indicated by the largest diameter of the inhibition zone against the fungus Colletotrichum gloeosporioides, namely 1.7 cm.
Identifikasi Struktur Protein Spike Varian Baru SARS-CoV-2 secara Bioinformatika dalam Pengembangan Kandidat Terapi COVID-19 Taufik Muhammad Fakih; Dwi Syah Fitra Ramadhan; Aulia Fikri Hidayat; Budi Prabowo Soewondo
Jurnal Riset Kimia Vol. 14 No. 2 (2023): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i2.552

Abstract

Despite the relatively slow evolutionary rate of SARS-CoV-2 in comparison to other RNA viruses, the extensive and rapid transmission during the COVID-19 pandemic has led to the emergence of significant genetic diversity since the virus first infected the human population. This has resulted in various variants, such as Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), among others. Of particular concern are the Delta Variant and newly recognized Variants of Concern (VOCs), including lineages of B.1.617.2, as well as other VOCs discovered through local transmission, such as Epsilon (B.1.427/29-US) and B1.1.7/E484K-UK. The interactions between these variants and the spike protein of SARS-CoV-2, as well as the Angiotensin-converting enzyme 2 (ACE2), have become a primary focus in understanding the infection and spread of the SARS-CoV-2 virus. This research aims to comprehensively identify, evaluate, and explore the structural characteristics of the macromolecular spike protein of SARS-CoV-2 in the Beta, Gamma, and Delta variants using bioinformatics approaches. The methods employed in this study include homology modeling, molecular docking simulations, and molecular dynamics simulations. The research findings indicate that the spike protein of SARS-CoV-2 in the Gamma variant exhibits a strong affinity for ACE2. Therefore, this study is expected to serve as a reference for designing effective vaccine or antiviral candidates targeting various SARS-CoV-2 variants in the treatment of COVID-19 infections.
Pembuatan dan Karakterisasi BPAC (Banana Peels Activated Carbon) Sebagai Biosorben Logam Raksa (Hg) dengan Aktivator HCl Putri Ade Rahma Yulis; Asyti Febliza
Jurnal Riset Kimia Vol. 14 No. 2 (2023): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i2.596

Abstract

Based on the 2021 Central Statistics Agency (BPS) about environment, there is still a high level of pollution, especially pollution in water. The pollution is dominated by heavy metal contaminants. This research was carried out to make and characterized biosorbents which were activated into activated carbon from banana peel waste called BPAC (Banana Peels Activated Carbon) with HCl activator. Activated carbon has many advantages as an adsorbent with time and cost efficiency in absorbed heavy metals. Activated carbon from banana peels that has been formed was tested for its characterization included tests for water content, ash content, and iodine absorption and compared with SNI standard activated carbon quality with results of 3.9% water content, 6.2% ash content and iodine absorption 563.6 mg/g. The functional groups were tested by FT-IR (Fourier Transform-Infra Red) with the result spectrum at the peak of 3334 cm-1, 2921 cm-1,  2853 cm-1, 1575 cm-1, 1375 cm-1, and 1098 cm-1 which indicated the presence of functional groups such as (C-O); (C=O); (C-H); (O-H) of several compounds such as lignin, pectin, cellulose and galacturonic acid as active sites that can bind heavy metals such as mercury. Surface morphology of activated carbon was tested by SEM (Scanning Electron Microscopy) with 500x and 1000x magnification. Activated carbon that has been tested is then applied to artificial mercury metal waste to determine the adsorption power and effectiveness of the activated carbon. Mercury metal content before adsorption was 6.995 mg/L and after adsorption was 0.0084 mg/L which was measured used ICP-OES (Inductively Coupled Plasma – Optical Emission Spectrometry). The percentage effectiveness of BPAC (Banana Peels Activated Carbon) reaches 99.87% with an adsorption capacity of 0.698 mg/g. Based on the results of this percentage it can be said that BPAC is effective to be used as a metal mercury biosorbent.
Komposit Zeolit-Polivinil Alkohol sebagai Adsorben untuk Menurunkan Kesadahan Air Tanah Anang Takwanto; Yanty Maryanty; Anugrah Windy Mustikarini; Dina Wulan Sari; Rizki Kurnia Juliansyah
Jurnal Riset Kimia Vol. 14 No. 2 (2023): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i2.597

Abstract

Granular zeolite-polyvinyl alcohol (PVA) composites without glutralaldehyde and zeolite-PVA composites with the addition of glutaraldehyde were carried out in this study and used as adsorbents. This study aims to reduce groundwater hardness, determine the optimum zeolite size in composite mixtures, and determine the characterization of functional groups in composites. The stages of the research included: preparation and activation of zeolite with variations in zeolite sizes of 100, 60 and 45 mesh and variations in composition of zeolite-polyvinyl alcohol 1:1; 1:2; 2:1; 2:3 and 3:2. Furthermore, the preparation of PVA solution concentration of 9% and the formation of the composite. The results showed that the optimum size of the zeolite on the composite without glutaraldehyde was 60 mesh with a decrease in hardness of 68% while the ratio of the optimum zeolite-PVA composition was at a ratio of 3:2 with a decrease in hardness of 34 mg/L. The results of Langmuir and Freundlich isotherm analysis showed the presence of chemical bonds because the determination value (R2) of the adsorption isotherm was > 0.9. The results of functional group characterization showed OH- in the zeolite-PVA composite without glutaraldehyde at a wavelength of 3363.01 cm-1 while in the composite with glutaraldehyde at a wavelength of 3345.89 cm-1. The C=C functional group appeared at a wavelength of 1628.73 cm-1 for the zeolite-PVA composite without glutaraldehyde and 1635.86 cm-1 for the composite with glutaraldehyde. At a wavelength of 788.70 cm-1 and 794.40 cm-1, the Si-O symmetric stretching vibrations show in the zeolite structure.
Fitokimia, Kadar Fenolik Total, dan Flavonoid Total serta Aktivitas Antioksidan Ekstrak n-Heksana Rimpang Temu Hitam (Curcuma aeruginosa Roxb) Auliya Ilmiawati; Ika Resmeiliana; Ishika Jauza Nasywa; Fadia Fahira; Nafisa Muthia Wafa; M. Raffi Rayandhika; Andi Thaariq Muhammad; Arini Septianti; Hafizah Fatunisa
Jurnal Riset Kimia Vol. 14 No. 2 (2023): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i2.599

Abstract

The rhizome of black turmeric (Curcuma aeruginosa) is a plant rich in benefits and has been used as a herbal medicine to treat various health problems. This study aims to obtain the n-hexane extract of black turmeric rhizome and perform phytochemical tests, determine total phenolic and total flavonoid levels, as well antioxidant tests using the DPPH method. Extraction of n-hexane from black turmeric rhizome obtained yield of 4.88%, total phenolic content of 3.01 mg QE/g extract and total flavonoids of 6.31 mg QE/g extract. The phytochemical test obtained positive results for the presence of alkaloids and flavonoids; negative tannins, steroids/triterpenoids and saponins. Antioxidant tests using the DPPH method obtained the percentage of DPPH capture ranging from 76-78%, with the largest percentage value obtained when the extract concentration was 125 ppm, which was 78.02%. This shows that black turmeric n-hexane extract has weak antioxidant activity.
Pemanfaatan Zeolit Alam Ende Sebagai Katalis dalam Pirolisis Polietilena dari Sampah Plastik Gregorio Antonny Bani
Jurnal Riset Kimia Vol. 14 No. 2 (2023): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i2.607

Abstract

Pyrolysis is one way to minimise plastic waste. This process requires a catalyst such as zeolite. Natural zeolite needs to be activated to increase its catalytic activity. Therefore, this research was carried out by activating Ende's natural zeolite using 1% hydrofluoric acid (HF), 6M hydrochloric acid (HCl), and 1M ammonium chloride (NH4Cl) to be used as catalysts in the pyrolysis of polyethylene from plastic waste. Pyrolysis was carried out at operating temperatures of 300 oC, 350 oC, 400 oC, and 450 oC, and treated with a catalyst composition of 0%, 5%, 10%, and 15% from 1000 grams of polyethylene. Based on the results of the study, it was concluded that activation of Ende's natural zeolite could change the chemical and physical properties of Ende's natural zeolite, including crystallinity, surface area, pore volume, and pore radius, and acidity to serve as a catalyst. Treatment of 10% catalyst from 1000 mg of plastic at an operating temperature of 400oC reduced the activation energy to 4.371.1 cal/mol and produced 80% more paraffin fraction in polyethylene pyrolysis oil from plastic waste.
The Extracted Pectin from Ambarella Fruit Peel (Spondias dulcis) as Biosorbent in Adsorption of Cu(II) Metal Ions Trisna Kumala Sari; Elinda Fithriana; Indang Dewata; Desy Kurniawati; Romy Dwipa Yamesa Away
Jurnal Riset Kimia Vol. 14 No. 2 (2023): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v14i2.608

Abstract

Heavy metals are known to seriously injure land plants and animals, including humans, as well as marine species when present in contaminated water. For the batch adsorption technique used in this study, Cu(II) ions were removed from an aqueous solution using an inexpensive  environmentally friendly adsorbent prepared from the extracted pectin of ambarella fruit peel. The functional groups of the extracted pectin were studied using Fourier Transform Infrared Spectroscopy (FT-IR). Operational conditions like pH, contact time, and initial adsorbate concentration were investigated. FTIR characterization showed that pectin was successfully extracted from ambarella fruit peel with the appearance of the peaks at 3331.36 cm-1, 2924.02 cm-1, 1727.38 cm-1, 1626.20 cm-1, 1329.31cm−1, 1232.43cm−1, 994.18 cm−1 and these peaks have similar characteristic with a commercial pectin. The maximum uptake of Cu(II) ions was obtained at a pH of 4, a contact time of 90 min, an initial metal concentration of 150 ppm. The extracted pectin has an adsorption capacity of 6.5860 mg/g for the removal of Cu(II) ions from aqueous solution under the optimum adsorption conditions. In addition, the data obtained from contacting the extracted pectin of ambarella fruit peel in Batang Arau River water showed an adsorption capacity of 0.0376 mg/g. Therefore, the pectin that was extracted from the peel of the ambarella fruit could be used to filter out Cu(II) ions from aqueous solutions.

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