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ALCHEMY Jurnal Penelitian Kimia
Published by Universitas Sebelas Maret
ISSN : 14124092     EISSN : 24434183     DOI : -
Core Subject : Science, Social, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Environmental Science Materials Science & Nanotechnology
ALCHEMY Jurnal Penelitian Kimia is a chemistry journal published by Sebelas Maret University, Surakarta. ALCHEMY Jurnal Penelitian Kimia publishes original research articles or review articles in organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, biochemistry, and environmental chemistry.
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Articles 306 Documents
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Kajian Dehidroksilasi Termal Kaolin menjadi Metakaolin menggunakan Analisis Termogravimetri Aprilina Purbasari; Tjokorde Walmiki Samadhi
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 1 (2021): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.1.47337.105-112

Abstract

Kaolin merupakan mineral yang banyak dimanfaatkan di berbagai industri. Kaolin dapat diubah menjadi metakaolin yang lebih reaktif melalui proses dehidroksilasi termal. Pada penelitian ini, proses dehidroksilasi termal kaolin dari Bangka Belitung menjadi metakaolin dikaji menggunakan analisis termogravimetri pada rentang suhu 30 – 900 °C dengan laju pemanasan 10 °C/menit dalam lingkungan atmosfer udara. Kaolin mengalami empat tahap dekomposisi dan dehidroksilasi kaolin menjadi metakaolin terjadi pada suhu sekitar 450 – 600 °C. Berdasarkan metode Coats dan Redfern, dehidroksilasi kaolin mengikuti model reaksi order satu dengan energi aktivasi 271,66 kJ/mol dan faktor pre-eksponensial 6,13×1015 s-1. Hasil analisis menggunakan spektroskopi X-ray diffraction (XRD) dan Fourier Transform Infrared (FTIR) pada kaolin setelah dipanaskan pada suhu 550 °C selama 3 jam menunjukkan bahwa sebagian besar kaolin telah berubah menjadi metakaolin.Study of Thermal Dehydroxylation of Kaolin to Metakaolin using Thermogravimetric Analysis. Kaolin is a mineral that is widely used in various industries. Kaolin can be converted into metakaolin which is more reactive through thermal dehydroxylation processes. In this study, thermal dehydroxylation process of Bangka Belitung kaolin into metakaolin was studied using thermogravimetric analysis in a temperature range of 30 – 900 °C with a heating rate of 10 oC/min in an air atmosphere condition. Kaolin underwent four stages of decomposition and dehydroxylation of kaolin into metakaolin occured at temperatures around 450 – 600 °C. Based on the Coats and Redfern method, kaolin dehydroxylation followed first order reaction model with activation energy of 271.66 kJ/mol and pre-exponential factor of 6.13×1015 s-1. The analysis using X-ray diffraction (XRD) dan Fourier Transform Infrared (FTIR) spectroscopy on kaolin after heating at temperature of 550 °C for 3 hours showed that most of the kaolin had turned into metakaolin.
Virtual Screening Kandungan Senyawa Kipas Laut (Gorgonia mariae) sebagai Antiasma Faruk Jayanto Kelutur; Resmi Mustarichie; Abdul Kakhar Umar
ALCHEMY Jurnal Penelitian Kimia Vol 16, No 2 (2020): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.16.2.39965.199-210

Abstract

Kipas laut (Gorgonia mariae) telah digunakan masyarakat Maluku secara turun temurun sebagai obat asma. Kandungan metabolit sekunder yang paling dominan dalam kipas laut adalah sterol, dimana memiliki aktivitas terapi melalui efek sinergisme antara senyawa metabolit dengan polivalent activity. Pengujian kipas laut sebagai anti-asma belum pernah dilaporkan sebelumnya. Oleh karena itu, perlu dilakukan virtual screening menggunakan metode in silico pada komponen sterol kipas laut sebagai tahap awal dalam menentukan efektivitas terapi anti-asma dengan memprediksi nilai ikatan energi bebas (ΔG), konstanta inhibisi (Ki), dan interaksi residu asam amino menggunakan Autodock Tools 4.2 dan Discovery Studio 2016 Client®. Keamanan dan efektivitas kandidat obat dievaluasi menggunakan parameter dari Lipinski Rule of Five dan pre-ADMET. Hasil penelitian menunjukkan bahwa konstanta inhibisi dan ikatan energi bebas (Ki; ΔG) dari komponen senyawa kipas laut dapat diurutkan secara potensial yaitu 4,24-dimetil kolestanol  (0,809; -12,40) > 24-metil-22-dehidrokolesterol (0,864; -12,36) > 23-demetil gorgosterol (1,74; -11,95) > 4,24-dimetil-22-dehidrokolestanol (1,89; -11,90). Residu asam amino yang berperan penting dalam aktivitas inhibisi hCHIT1 adalah 213-ASP. Semua komponen senyawa uji memiliki nilai log P lebih dari 5 yang menunjukkan bahwa kelarutan dan toksisitas perlu diperhatikan. Evaluasi distribusi pre-ADMET berdasarkan nilai dari pengikatan protein plasma menunjukan bahwa senyawa uji dapat berdifusi menembus membran plasma dan berinteraksi sesuai target farmakologi. Selain itu, hasil parameter uji toksisitas menunjukkan bahwa senyawa 23-demetil gorgosterol dan 4,24-dimetil-22-dehidrokolestanol memiliki potensi sebagai anti-asma.Virtual Screening of the Compounds in Gorgonians (Gorgonia mariae) as anti-asthma. The people of Maluku have used Kipas laut (G. mariae) for generations as an asthma medicine. The secondary metabolite that is most dominant in kipas laut is sterols, which have therapeutic activity through the synergistic effect between metabolite compounds and polyvalent activity. Anti-asthma activity of kipas laut has never been reported. Therefore, it is necessary to do virtual screening using the in silico method on the sterol component of kipas laut as a first step in determining the effectiveness of anti-asthma therapy by predicting the value of free energy bonds (ΔG), constant inhibition (Ki), and interactions of amino acid residues using Autodock Tools 4.2 and Discovery Studio 2016 Client®. The effectiveness and safety of prospective drugs are evaluated using the Lipinski Rule of Five and pre-ADMET. The results showed that the value of inhibition constants and free energy bonds (Ki; ΔG) on the compound of kipas laut that was potentially sorted was 4.24-dimethyl cholestanol (0.809; -12.40) > 24-methyl-22-dehydrocholesterol (0.864; -12.36) > 23-demethyl gorgosterol (1.74; -11.95) > 4.24-dimethyl-22-dehidrokolestanol (1.89; -11.90). The crucial residues of amino acids is 213-ASP, which play a significant role in hCHIT1 inhibitory activity. All components of the test compound have a log P value of more than five, which indicates that solubility and toxicity need to be considered. Evaluation of the pre-ADMET based on the value of plasma protein binding shows that the test compound can diffuse through the plasma membrane and interact according to pharmacological targets. In addition, the results of the toxicity test showed that 23-demethyl gorgosterol and 4.24-dimethyl-22-dehidrokolestanol compounds have potential as anti-asthma.
Pemanfaatan Kitosan dari Cangkang Kepiting Bakau (Scylla serrata) dengan Metode Microwave sebagai Bahan Dasar Kapsul Obat Mashuni Mashuni; Muhammad Natsir; Wahyuni Mia Lestari; Fitri Handayani Hamid; Muhammad Jahiding
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 1 (2021): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.1.42038.74-82

Abstract

Cangkang kepiting bakau (Scylla serrata) mengandung senyawa kitin  yang dapat ditransformasi menjadi kitosan sebagai bahan pembuatan kapsul obat. Proses transfomasi ini masih perlu untuk dikembangkan lanjut. Penelitian ini bertujuan untuk menghasilkan kapsul obat berbahan dasar cangkang kepiting bakau dengan metode microwave. Metode isolasi kitin dari cangkang kepiting bakau meliputi proses deproteinasi, demineralisasi, dan dekolorisasi. Sintesis kitosan menggunakan metode microwave (daya 450 watt selama 15 menit) dalam pelarut NaOH 50% (b/v) dengan perbandingan 1:20 (b/v), selanjutnya kitosan dihidrolisis menggunakan larutan HCl 20% (v/v) untuk menghasilkan glukosamin hidroklorida (GlcN HCl). Pembuatan kapsul obat dengan perbandingan GlcN HCl dan larutan sukrosa yaitu masing-masing 3:1, 3:3, dan 3:5. Rendemen kitosan yang diperoleh sebanyak 37,5% dengan derajat deasetilasi 83,8%. Kapsul obat diperoleh perlakuan terbaik pada perbandingan GlcN HCl-larutan sukrosa 3:1. Berdasarkan analisis terhadap spektra kapsul obat, diidentifikasi adanya gugus O−H, −CH3, N−H, C−N, C−O, dan β-1,4-glikosidik. Karakteristik sifat fisik menunjukkan bahwa kapsul obat memiliki kadar air 12,7%, uji waktu hancur 13 menit 34 detik dan kelarutan dalam asam 3 menit 17 detik. Hasil penelitian menunjukkan bahwa kitosan cangkang kepiting bakau telah memenuhi kriteria bahan dasar kapsul obat sesuai kriteria farmakope Indonesia.Utilization of Chitosan from Mangrove Crab Shell (Scylla serrata) using the Microwave Method as a Base Material for Medicinal Capsules. The mangrove crab shell (Scyllaserrata) contains a chitin compound potentially transformed into chitosan as an ingredient for medicinal capsules. The research on this transformation process needs further developments. This research aims to produce chitin-based medicinal capsules of mangrove crab shells by microwave methods. The chitin isolation method of mangrove crab shells covers the process of deproteinization, demineralization, and decoloration. The synthesis of chitosan used microwave methods (450 watts of power for 15 minutes) in the solvent of 50% NaOH (w/v) with a ratio of 1:20 (b/v). Chitosan was then hydrolyzed using 20% HCl (v/v) solution to produce glucosamine hydrochloride (GlcN HCl). Preparation of drug capsules with a ratio of GlcN HCl and sucrose solution, namely 3:1, 3:3, and 3:5, respectively. The chitosan yield was obtained as much as 37.5% with a deacetylation degree of 83.8%. The best treatment of the medicinal capsules was obtained on the ratio of GlcN HCl and sucrose solution 3:1. The FTIR analysis of medicinal capsules are identified by the presence of the O−H, −CH3, N−H, C−N, C−O, and β-1.4-glycosidic. The physical characterization showed that the medicinal capsules have a water content of 12.7%, the test of destroyed time of 13 minutes 34 seconds, and soluble in acid that is 3 minutes 17 seconds. The results show that chitosan prepared from mangrove crab shell is potentially used as a basic ingredient for medicinal capsules because it met the criteria for Indonesian pharmacopoeial capsules.
Pengaruh Penggantian Kation-A/Sr oleh Ba pada Morfologi Partikel BaxSr(1-x)TiO3 (x = 0; 0,2; 0,4; 0,6; 0,8) Hasil Sintesis dengan Metode Lelehan Garam Hasal Maulidianingtiyas; Aldi Dwi Prasetiyo; Fikri Haikal; Indra Nur Cahyo; Vina Nurul Istighfarini; Anton Prasetyo
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 2 (2021): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.2.48554.211-218

Abstract

SrTiO3 adalah material berstruktur perovskit yang dilaporkan berpotensi sebagai material fotokatalis. Penggantian pada sebagian kation-A material fotokatalis berstruktur perovskit dilaporkan dapat menurunkan energi celah pitanya, akan tetapi unsur pengganti juga dilaporkan mempengaruhi morfologi partikel yang terbentuk. Dalam penelitian ini, dikaji pengaruh penggantian kation-A pada SrTiO3(BaxSr(1-x)TiO3 (x = 0; 0,2; 0,4; 0,6; 0,8)) terhadap morfologi partikelnya. Senyawa uji disintesis dengan metode lelehan garam dan dalam penelitian ini menggunakan garam NaCl. Difraktogram sampel menunjukkan bahwa senyawa uji berhasil disintesis kecuali pada x = 0,8 masih ditemukan senyawa pengotor yang berupa TiO2 dan BaCO3. Gambar SEM menunjukkan bahwa keberadaan kation Ba mengubah morfologi partikel dari nearly cubic menjadi bentuk polihedra dan menyebabkanukuran partikel menjadi lebih besar.The Effect of Cation-A/Sr Replacement by Ba on Particle Morphology of BaxSr(1-x)TiO3 (x = 0; 0.2; 0.4; 0.6; 0.8) Synthesized by Molten Salt Method. SrTiO3 is a perovskite structure material that is reported as a potential photocatalyst material. Replacement of a part of the A-cation on a perovskite structure was reported can reduce its bandgap energy. However, the replacement element was also reported to affect the particle morphology. In this study, the effect of A-cation replacement on SrTiO3 (BaxSr(1-x)TiO3 (x = 0, 0.2, 0.4, 0.6, 0.8) to its particle morphology was studied. The sample of BaxSr(1-x)TiO3 (x = 0, 0.2, 0.4, 0.6) were synthesized by molten salt synthesis method (using NaCl salt). The diffractogram showed that the target compound was successfully synthesized but at x = 0.8 still found impurities TiO2 and BaCO3. SEM images showed that Ba-cation presence changes the particle morphology from nearly cubic to polyhedral shape and the particle size also becomes larger. 
A New Limonoid from the Seeds of Chisocheton lasiocarpus (Meliaceae) Ronauli Fitriana; Nurlelasari Nurlelasari; Darwati Darwati; Desi Harneti; Rani Maharani; Tri Mayanti; Unang Supratman
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 2 (2021): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.2.44782.219-226

Abstract

 A New Limonoid from the Seeds of Chisocheton lasiocarpus (Meliaceae). Chisocheton is one of Meliaceae genus, which has about 53 species spreading in subtropical and tropical regions. One of the species is Chisocheton lasiocarpus. Chisocheton is rich in limonoids that have various biological activities such as anticancer, antimalarial, anti-inflammatory, antifeedant, antiviral, neuroprotective, and antimicrobial properties. This study aims to isolate limonoids from the seeds of C. lasiocarpus, and determine the structures. The dry powder of seeds of C. lasiocarpus (203.75 g) was macerated with subsequent n-hexane, ethyl acetate, and methanol. Extract of ethyl acetate was separated and purified using chromatography methods until a new limonoid, lasiocarpines (1) and one known limonoid, 14β,15β-epoxynimonol (2) were obtained. The purification process was guided by Ehrlich reagent. The chemical structures were identified by UV, IR, 1H-NMR, 13C-NMR, 2D NMR, and mass spectrometry.
Pengaruh Bentonit terhadap Pembentukan Fasa Polimorf dan Sifat Termal Membran Hibrida Poliviniliden Fluorida/Bentonit Edi Pramono; Rosid Eka Mustofa; Ozi Adi Saputra; Yulianto Adi Nugroho; Deana Wahyunigrum; Cynthia Linaya Radiman; Sayekti Wahyuningsih; Teguh Endah Saraswati; Sentot Budi Rahardjo; Witri Wahyu Lestari; Dian Maruto Widjonarko; Ari Handono Ramelan
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 2 (2021): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.2.46136.177-184

Abstract

Kajian struktur dan degradasi termal pada membran hibrida poliviniliden fluorida (PVDF)/lempung bentonit (BNT) telah dilakukan. Penelitian ini bertujuan mengetahui pengaruh penambahan BNT terhadap pembentukan fasa PVDF dan sifat termalnya. Membran hibrida PVDF/lempung BNT dibuat dengan metode inversi fasa. Membran yang dihasilkan dikarakterisasi dengan attenuated total reflectance fourier transform infrared (ATR-FTIR), x-ray diffraction (XRD), dan differential scanning calorimetry (DSC). Hasil penelitian menunjukkan membran PVDF/BNT memiliki struktur polimorf PVDF fasa α dan β yang terkonfirmasi dari data FTIR dan XRD. Data DSC menunjukkan penurunan nilai titik leleh (Tm) dengan penambahan BNT, dan dengan rentang suhu pelelehan yang lebih kecil. Kristalisasi PVDF terjadi secara isothermal dan adanya BNT menghasilkan titik kristalisasi (Tc) pada suhu yang lebih tinggi dibandingkan membran PVDF murni. Analisis termal dengan DSC memberikan informasi komprehensif pelelehan dan kristalisasi dari polimorf PVDF pada matriks membran.Effect of Bentonite toward Polymorph Phase Formation and Thermal Properties of Polyvinylidene Fluoride/Bentonite Hybrid Membranes. The study of the structure and thermal properties of PVDF/bentonite (BNT) hybrid membranes has been carried out. This study aims to determine the effect of BNT addition on the phase formation and thermal properties of the PVDF. In this study, PVDF/BNT hybrid membranes were prepared through the phase inversion method. The resulting membrane was characterized by Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR), x-ray diffraction (XRD), and differential scanning calorimetry (DSC). The results showed that the PVDF/BNT membrane has a PVDF polymorph structure with α and β phases confirmed by FTIR and XRD data. The DSC data showed that the addition of BNT decrease of the melting point (Tm) and with a smaller melting temperature range. PVDF polymorph crystallization occurs isothermally and the presence of BNT produces a crystallization point (Tc) at a higher temperature than pristine PVDF membrane. Thermal analysis with DSC provides comprehensive information on melting and crystallization of PVDF polymorphs in the membrane matrix.
Sintesis, Karakterisasi dan Kinerja Membran Hidrofobik Menggunakan Polyvinyl Pyrrolidone (PVP) sebagai Aditif Umi Fathanah; Mirna Rahmah Lubis; Zuhra Mahyuddin; Syawaliah Muchtar; Mukramah Yusuf; Cut Meurah Rosnelly; Sri Mulyati; Rina Hazliani; Devi Rahmanda; Suraiya Kamaruzzaman; Meuthia Busthan
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 2 (2021): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.2.48435.140-150

Abstract

Artikel ini melaporkan tentang sintesis, karakterisasi dan kinerja membran polyethersulfone (PES) yang dimodifikasi dengan aditif polyvinyl pyrrolidone (PVP) dengan tujuan untuk meningkatkan kinerja dan sifat antifouling membran. Membran PES modifikasi dibuat dengan penambahan 0,5% PVP sebagai aditif, menggunakan pelarut dimethyl sulfoxide (DMSO) dan n-methyl pyrrolidone (NMP). Pengaruh penambahan aditif dalam sistem membran dievaluasi dengan menganalisa perubahan struktur kimia menggunakan fourier transform infrared (FTIR), perubahan morfologi permukaan menggunakan scanning electron microscopy (SEM), uji kuat tarik menggunakan tensile strength meter, uji porositas membran dengan menggunakan metode gravimetri, serta pengujian kinerja filtrasi, dan sifat antifouling. Hasil analisa struktur membran dengan SEM menunjukkan adanya pengaruh jenis pelarut dan penambahan aditif terhadap perubahan morfologi membran. Selain itu modifikasi membran juga meningkatkan porositas, kinerja fluks permeasi serta sifat antifouling membran. Hasil uji filtrasi membran menunjukkan perolehan permeabilitas air pada membran D-0,5 dan N-0,5 masing masing sebesar 47,5 L/m2.jam.atm dan 41,5 L/m2.jam.atm dengan sifat antifouling membran modifikasi lebih besar dibandingkan dengan membran tanpa modifikasi. Synthesis, Characterization, and Performance of Hydrophobic Membranes Using Polyvinyl Pyrrolidone (PVP) as Additives. This paper discusses the synthesis, characterization and performance of polyethersulfone (PES) membranes modified with polyvinyl pyrrolidone (PVP) additives in order to improve the performance and antifouling properties of membranes. The modified PES membrane was prepared by adding 0.5% PVP as an additive, using dimethyl sulfoxide (DMSO) and n-methyl pyrrolidone (NMP) as solvents. The effect of adding additives to the membrane system was evaluated by analyzing changes in chemical structure using fourier transform infrared (FTIR), changes in surface morphology using scanning electron microscopy (SEM), tensile strength test using tensile strength meter, membrane porosity test using the gravimetric method, as well as testing the filtration performance and antifoulingproperties. The results of membrane structure analysis by SEM showed the influence of the type of solvent and additives on changes in membrane morphology. In addition, membrane modification also increases porosity, permeation flux performance, and membrane antifouling properties. The results of the membrane filtration test showed that the water permeability of D-0.5 and N-0.5 membranes was 47.5 L/m2.h.atm and 41.5 L/m2.h.atm, respectively, with modified membrane antifouling properties larger than the membrane without modification.
Analisis Logam Cr(III) Hasil Reduksi Cr(VI) dengan Teknik Voltammetri Lucutan Menggunakan Elektroda Pasta Karbon Termodifikasi EDTA: Studi Pendahuluan Annisa Anggitami; Dian Ayu Setyorini; Muhammad Yudhistira Azis; Ria Sri Rahayu
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 2 (2021): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.2.47875.185-191

Abstract

Pada penelitian ini dikembangkan suatu metode pengukuran Cr(III) menggunakan elektroda pasta karbon (EPK) yang termodifikasi EDTA yang dapat diaplikasikan dalam penentuan efektivitas reduksi limbah Cr(VI) serta penentuan Cr(VI) dalam suatu sampel secara tidak langsung. Metode analisis voltammetri yang dilakukan menggunakan teknik voltammetri siklik, differential pulse voltammetry dan square wave voltammetry. EDTA merupakan ligan polidentat yang dapat mengkelat beberapa logam. Untuk logam kromium, EDTA hanya bisa mengkelat Cr(III). Oleh karena itu, dalam proses pengukurannya dilakukan reduksi Cr(VI) menjadi Cr(III) yang kemudian dapat dianalisis menggunakan EPK yang termodifikasi EDTA. Teknik voltammetri dipilih karena memiliki sensitivitas yang tinggi, limit deteksi yang rendah, dan memiliki daerah linier yang lebar. Hasil penelitian memperoleh bahwa Cr(III) dapat dianalisis dengan EPK termodifikasi EDTA menggunakan teknik voltammetri lucutan. Kondisi optimum pengukuran yang diperoleh adalah menggunakan elektroda dengan komposisi grafit: EDTA 25% berat (w/w), larutan elektrolit NaCl 0,1 M, waktu deposisi 5 detik, dan potensial deposisi 300 mV. Carbon Paste Electrode Modified by EDTA for Determination of Cr(III) Reduced from Cr(VI) by Using Stripping Voltammetry Method: A Preliminary Study. This study presented a method of measuring Cr(III) using carbon paste electrodes (CPE) modified by EDTA, which could be applied in determining Cr(VI) waste indirectly. EDTA is a polydentate ligand that can chelate several metals. For chromium metal, EDTA can only chelate Cr(III). Therefore, a reduction of Cr(VI) to Cr(III) was carried out in the measurement process and then analyzed using an EDTA-modified carbon paste electrode. The technique was chosen because it has a high sensitivity, low detection limit, and has a wide linear area. The results showed that Cr(III) could be analyzed using EDTA-modified CPE using stripping voltammetry. The optimum measurement conditions obtained were using an electrode with a composition of 25% weight (w/w) EDTA, 0.1 M NaCl as supporting electrolyte, 5 seconds for deposition time, and 300 mV for deposition potential.
Biodegradasi Pewarna Tekstil Rhodamin B oleh Bakteri Pembentuk Biofilm Sitti Wirdhana Ahmad; Nur Arfa Yanti; Fatimah Alwi Albakar
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 2 (2021): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.2.49010.151-158

Abstract

Rhodamin B merupakan salah satu pewarna yang paling sering digunakan pada industri tekstil. Limbah pewarna tekstil ini dapat mencemari lingkungan jika masuk ke lingkungan melebihi ambang batas normal. Penggunaan bakteri pembentuk biofilm sebagai agensia pendegradasi Rhodamin B sangat memungkinkan karena mampu meningkatkan degradasi senyawa melalui interaksi antar bakteri sehingga mampu melengkapi proses metabolik. Tujuan penelitian ini adalah untuk mengetahui kemampuan isolat bakteri lokal pembentuk biofilm dalam mendegradasi pewarna tekstil Rhodamin B. Penelitian ini menggunakan 3 isolat bakteri pembentuk biofilm yang diperoleh dari perairan Tanjung Tiram, Kabupaten Konawe Selatan, Sulawesi Tenggara, yaitu isolat bakteri Chromohalobactersp. BfTT2.1.5, Bacillussp. BfTT2.11 dan Vibriosp. BfTT2.14. Kemampuan biodegradasi Rhodamin B oleh isolat bakteri pembentuk biofilm dideteksi menggunakan tiga parameter yaitu dekolorisasi pewarna Rhodamin B menggunakan metode spektrofotometri, kadar CO2 terlarut menggunakan metode titrasi dan total sel bakteri menggunakan metode drop plate. Berdasarkan uji kemampuan dalam mendegradasi pewarna tekstil Rhodamin B, Chromohalobacter sp. BfTT2.1.5 mampu mendegradasi Rhodamin B sebanyak 36,1% lebih tinggi dibanding Bacillus sp. BfTT2.11 (33,24%) dan Vibriosp. BfTT2.14 (16,18%). Ketiga isolat bakteri pembentuk biofilm mampu menggunakan Rhodamin B sebagai sumber karbon untuk pertumbuhannya. Oleh karena itu, isolat bakteri pembentuk biofilm sangat berpotensi digunakan sebagai agensia bioremediasi pewarna tekstil Rhodamin B.Biodegradation of Textile Dye Rhodamine B Using Biofilm-forming Bacteria. Rhodamine B is one of the most widely used dyes in the textile industry. This textile dye waste can pollute the environment if it enters the environment beyond the normal threshold. The use of biofilm-forming bacteria as agents to degrade Rhodamine B is possible because it can increase the degradation of compounds through interactions between bacteria to complete the metabolic process. The purpose of this study was to find out the resistance of local biofilm-forming bacteria isolates to Rhodamine B textile dyes and to find out the ability of local biofilm-forming bacterial isolates in degrading Rhodamine B textile dyes. This study used three isolates of biofilm-producing bacteria obtained from the waters of Tanjung Tiram, Konawe Selatan Regency, Southeast Sulawesi, namely Chromohalobactersp. BfTT2.1.5, Bacillussp. BfTT2.11 dan Vibriosp. BfTT2.14 bacterial isolates. The ability of biofilm-forming bacteria isolates to degrade Rhodamine B was detected using three parameters including decolorization of Rhodamine B dye using a spectrophotometry method, dissolved CO2 levels using the titration method, and total bacterial cells using the drop plate method. The results show that the isolate bacteria Chromohalobacter sp. BfTT2.1.5 is able to degrade Rhodamine B as much as 36.1% higher than Bacillus sp. BfTT2.11 (33.24%) and Vibriosp. BfTT2.14 (16.18%). The three biofilm-forming bacteria isolates were able to use Rhodamine B as a carbon source for growth. Therefore, the local isolates biofilm-forming bacteria are potential to be used as bioremediation agents for Rhodamine B textile dyes.
Senyawa Steroid dari Cocor Bebek (Kalanchoe tomentosa) sebagai Antibakteri Pseudomonas aeruginosa Risyandi Anwar; Lilis Siti Aisyah; Faridia Puspita Lestari; Delia Ilfani; Yenny Febriani Yun; Pebrian Diki Prestya
ALCHEMY Jurnal Penelitian Kimia Vol 17, No 2 (2021): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.17.2.51285.202-210

Abstract

Plak adalah pembentukan komunitas bakteri yang terorganisir pada permukaan gigi yang berupa lapisan tipis tidak berwarna. Pseudomonas aeruginosa adalah salah satu bakteri yang sangat berperan pada pembentukan plak. Metabolit sekunder yang terkandung dalam tanaman Kalanchoe tomentosa dapat digunakan sebagai antibakteri. Tahapan penelitian diawali dengan maserasi menggunakan pelarut n-heksan dan diklorometana. Ekstrak diklorometana dipisahkan menggunakan Kromatografi Cair Vakum (KCV) dengan n-heksana dan etil asetat sebagai pelarut bergradien selanjutnya direkristalisasi dengan n-heksan, hasil rekristalisasi didapatkan isolat 1. Isolat 1 dikarakterisasi dengan spektroskopi infra-red (IR), ultraviolet (UV) dan nuclear magnetic resonance hydrogen (1H NMR) serta dibandingkan dengan literatur. Isolat 1 diketahui merupakan stigmast-5-en-3ꞵ-ol atau ꞵ-sitosterol. Pada ekstrak diklorometana dan senyawa ꞵ-sitosterol kemudian ditentukan aktivitas antibakteri secara mikrodilusi didapatkan hasil bahwa ekstrak diklorometana dan senyawa ꞵ-sitosterol bukan hanya menunjukan sifat bakteriostatik tetapi juga bakterisid kuat terhadap bakteri Pseudomonas aeruginosadengan nilai Konsentrasi Hambat Minimum (KHM) <100 µg/mL.Steroid Compounds from Cocor Bebek (Kalanchoe tomentosa) as Antibacterial Pseudomonas aeruginosa. Plaque is a thin, colorless layer that adheres tightly to the surface of the teeth and contains a collection of bacteria. One of the bacteria that can form dental plaque is Porphyromonas aeruginosa. Kalanchoe tomentosa contain secondary metabolite which can be used as antibacterial. Stages of the study begin with maceration using n-hexane and dichloromethane. Dichloromethane extract was separated using Vacuum Liquid Chromatography (KCV) using n-hexane and ethyl acetate solvents and then recrystallized with n-hexane, the recrystallization results were obtained by isolate 1. Isolate 1 was marked by IR spectroscopy, and 1HNMR and compared with literature. Isolate 1 is known as stigmast-5-en-3ꞵ-ol or ꞵ-sitosterol. In dichloromethane extracts and ꞵ-sitosterol is determined by microdilution by microdilution. The results showed that dichloromethane extract and ꞵ-sitosterol compound not only showed strong bacteriostatic but also bacterisid activity against P. aeruginosa with Minimum Inhibiroty Concentration (MIC) <100 μg / mL.

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