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Teguh Endah Saraswati
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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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MATHEMATICAL MODELS AND THERMODYNAMIC PROPERTIES OF MOISTURE SORPTION ISOTHERMS OF FERMENTED CASSAVA FLOUR BY RED YEAST RICE Mutiara Nur Alfiah; Sri Hartini; Margareta Novian Cahyanti
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 1 (2017): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.1.4326.29-40

Abstract

This research aims to determine moisture sorption isotherm curves, moisture sorption isotherm models and thermodynamic properties of fermented cassava flour by red yeast rice. The moisture sorption isotherm model used are Guggenheim Anderson deBoer (GAB), Brunauer Emmet Teller (BET) and Caurie. Meanwhile, the test of modelling accuray by Mean Relative Deviation (MRD) and Root Mean Square Error (RMSE). The thermodynamic properties, i.e., enthalpy and entropy were calculated by Clausius - Clapeyron equation. The result shows that the moisture sorption isotherm curve on fermented cassava flour in a sigmoid form (type II). The GAB model is the best model for moisture sorption isotherm of fermented cassava flour by red yeast rice. The MRD and RMSE values at 30˚C, 35˚C and 40˚C are 3.12%, 2.71%, 3.81%, and 1.01, 0.35, 0.42, respectively. The monolayer moisture content at 30˚C, 35˚C and 40˚C are 6.61%, 6.27% and 6.91%, based on GAB model. Meanwhile, when the BET model was used, the monolayer moisture content are 4.92%, 4.86% and 5.19%, while by Caurie model are 6.37%, 6.18% and 5.30%, at 30˚C, 35˚C and 40˚C, respectively. The enthalpy and entropy of water sorption process were decreased when moisture content increased.
APPLICATION OF HPLC-BASED METABOLOMICS TO IDENTIFY RETENTION TIMES ANTIBACTERIAL COMPONENTS OF Stapylococcus aureus FROM KECOMBRANG FLOWER EXTRACT (Etlingera elatior) Wahyu Haryati Maser; Nancy Dewi Yuliana
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 2 (2017): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.2.4890.239-249

Abstract

Kecombrang (Etlingera elatior) is a well-known herb in Indonesia that is widely used in traditional medicine and as a flavour in local dishes. The aim of this study was to identify retention time of antibacterial components from kecombrang flower extract (Etlingera elatior) by HPLC-based metabolomics method. The antibacterial activity of ethanol extracts, chloroform, and water fractions was assessed by well-diffusion agar method against Staphylococcus aureus. Only chloroform fraction showed medium inhibition activity against Staphylococcus aureus. The HPLC chemical profiles of the fractions were then correlated to their antibacterial activity profile by means of Orthogonal Projection to Latent Sructure (OPLS) analysis. Peak area with retention time of 0.96 - 1.12 min present in chloroform fraction at UV 250 nm was found to significantly correlate to the antibacterial activity (Y related coefficient value 0.73).
Identifikasi Senyawa Kimia dalam Buah Kundur (Benincasa hispida (Thunb) Cogn.) dengan Kromatografi Gas-Spektrometer Massa (KG-SM) Venty Suryanti; Soerya Dewi Marliyana; Musmualim Musmualim
ALCHEMY Jurnal Penelitian Kimia Vol 14, No 1 (2018): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.14.1.13496.84-94

Abstract

Telah dilakukan isolasi dan identifikasi senyawa kimia buah kundur (Benincasa hispida). Komponen non polar dipisahkan dengan metode ekstraksi soxhlet selama 24 jam menggunakan pelarut petroleum eter. Residu dari ekstraksi soxhlet selanjutnya dimaserasi selama 24 jam menggunakan pelarut etanol. Terhadap ekstrak etanol selanjutnya dilakukan pemisahan senyawa kimia dengan kromatografi kolom menggunakan pelarut heksana, campuran heksana dengan etanol dan etanol. Fraksi yang telah terisolasi diidentifikasi dengan Kromatografi Gas-Spektrometer Massa (KG-SM). Senyawa yang berhasil teridentifikasi adalah tridekananitril, pentadekananitril dan heptadekananitril.  Identification of Chemical Constituents of Kundur Fruit (Benincasa Hispida (Thunb) Cogn.) by Gas Chromatography-Mass Spectrometry (GC-MS). Isolation and identification of chemical compounds of the kundur fruit (Benincasa hispida) have been conducted. Non polar components were isolated by soxhlet extraction for 24 h using petroleum ether as solvent. The residu was extracted by maseration using ethanol for 24 h. To the ethanol extract was applied chromatography column for further isolation using hexane, mixtures of hexane-ethanol, and ethanol as eluents. The isolated compounds were then identified by Gas Chromatography-Mass Spectrometry (GC-MS). The identified compounds were tridecanenitrile, pentadecanenitrile and heptadecanenitrile
Biosynthesis of Biosurfactant by Pseudomonas aeruginosa Using Cassava Flour Industrial Wastewater as Media Venty Suryanti; Sri Hastuti; Desi Suci Handayani
ALCHEMY Jurnal Penelitian Kimia Vol 10, No 1 (2014): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.10.1.12.22-30

Abstract

Biosynthesis of biosurfactant by Pseudomonas aeruginosa have been prepared using cassava flour industrial wastewater (manipueira) as medium. The optimum condition of the biosurfactans biosynthesis was obtained using media containing nutrient broth and manipueira without centrifugation (NBM) with 4 days fermentation. UV-Vis and FT-IR spectra indicated that the biosurfactant was a rhamnolipid containing hydroxyl, ester, carbocylic and aliphatic carbon chain functional groups. Biosurfactant exhibited critical micelle concentration (CMC) value of 576  mg/L and surface tension value of 0.045  N/m. The biosurfactant was able to decrease the interface tension and form emulsion with benzene, toluene, gasoline and palm oil. This biosurfactant showed w/o emulsion system.
Photocatalytic Activity of TiO2 Nano Supported on Membrane Cellulose Acetate/Nata De Coco (CA/NDC) in Photodegradation of Methylene Blue Roro Ernia Prawithasari; Ilma Fadilah; Mudjijono Mudjijono; Teguh Endah Saraswati; Dwidjono Hadi Darwanto
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 1 (2015): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.1.113.90-101

Abstract

Study of synthesis and effectiveness of membrane catalyst of cellulose acetate/nata de coco-TiO2 nano (CA/NDC-TiO2 nano) in photodegradation of methylene blue in batch system has been investigated. TiO2nanoparticles were synthesized by hydrothermal method followed by calcination at 450oC. Scanning Electron Microscopy (SEM) images indicate nano TiO2 has been successfully synthesized with average particle diameter as 88,63±4,37 nm.  X-ray diffraction pattern (XRD) of nano TiO2  shows some characteristic peaks of anatase TiO2 were still existed. Membrane photocatalyst of CA/NDC- nano TiO2 was prepared via phase inversion method by mixing TiO2 nanoparticles with CA casting solution. Thermogravimetric analysis shows three decomposition steps of CA/NDC-nano membrane as well as CA/NDC membrane. Photodegradation of methylene blue was conducted with nano-TiO2  particles and CA/NDC-TiO2 membrane for 50 minutes in batch system. The absorbance changes were measured by spectrophotometer at wavelength of 664.6 nm. The result shows the photodegradation rections tended to follow second order reaction. According to the rate constant value, k, the photocatalytic effectivity using CA-NDC/nano TiO2 membrane and nano TiO2photocatalysts in metilen blue photodegradation, statistically were not significantly different.
Modification of Carbon Paste Electrode with Crown Ether (Dibenzo-18-Crown-6) for Ascorbic Acid Analysis Using Differential Pulse Voltammetry Method Irdhawati Irdhawati; Manuntun Manurung; Anisha Maulinasari
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 2 (2015): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.2.728.175-191

Abstract

In this research, the modified carbon paste electrode with crown ether (dibenzo-18-crown-6) has been prepared, for determination of ascorbic acid. Some of parameters observed were optimization of crown ether composition in carbon paste, pH of solution, linear concentration range, limit of detection, reproducibility, and recovery. The optimum performance of the prepared electrode was applied for determination of commercialsampleswhich contain of ascorbic acid. The result of this research showsthat the optimum composition of crown ether in carbon paste is 0.6 % at pH 4. Linear range of concentration obtained is from 2 - 200 μM. The detection limit and percentage of recovery are 1.243 μM and 101.31 %, respectively. The modified electrode has HorRat value less than 2, it indicates a good reproducibility. Analysis of 4 commercial samples which contain of ascorbic acid were in agreement with the content listed in the label with the suitability of 94 - 100 %.
EFFECTS OF HEATING TEMPERATURE AND BINDER IN THE PRODUCTION OF CHAR-BASED ELECTRICAL CONDUCTOR Teguh Endah Saraswati; Achmad Bahrudin; Miftahul Anwar
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 2 (2016): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.2.708.167-178

Abstract

Graphite as one alotrof carbon is widely used as an electrode material for a good electrical conductivity properties. Charcoal as a carbon source material was found very abundant in nature. Charcoal has the potential application for electrode material in energy storage such as in a battery or supercapacitor. For this purpose, charcoal amorphous structure needs to be converted into a graphite structure so that it has better electrical conductivity property. This research aims to prepare the electrical conductor material derived from wood charcoal that could potentially be used as an electrode. Preparation was made by mixing charcoal powder with asphalt binder with a weight ratio of 3:1, 4:1, 5:1 and followed by heat treatment under an inert atmosphere at temperature of 600°C, 800°C and 1000°C. Charcoal material which was originally to be an electrical insulator has been successfully converted into an electrical conductor. The achievement of the optimum temperature to produce electrodes with the smallest electrical resistance is then applied to the manufacture of carbon electrodes by heating a mixture of charcoal and fructose binder in a weight ratio of 1:1 (w/w). The results showed electrodes with a mixture of charcoal powder and fructose with heat treatment at 1000°C has the better electrical conductivity among other variations.
Kajian Metal–Organic Frameworks (MOFS) sebagai Material Baru Pengantar Obat Qonita Awliya Hanif; Reva Edra Nugraha; Witri Wahyu Lestari
ALCHEMY Jurnal Penelitian Kimia Vol 14, No 1 (2018): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.14.1.8218.16-36

Abstract

Metal–Organic Frameworks (MOFs) merupakan material berpori baru yang berpotensi sebagai pengantar dan pelepas lambat obat. Strukturnya yang fleksibel, ukuran pori kristalin yang teratur, dan sisi koordinasi yang beragam merupakan beberapa kelebihan dari MOFs yang mendukung dalam enkapsulasi berbagai obat. Metode yang dapat digunakan untuk sintesis MOFs diantaranya nanopresipitasi, solvothermal, reverse microemulsion, dan reaksi solvothermal dengan template surfaktan. Karakterisasi material hasil sintesis maupun profil setelah enkapsulasi (loading) dapat dilakukan menggunakan Scanning Electron Micrscope (SEM), Transmission Electron Microscope (TEM), Differential Scanning Calorymetry (DSC), Fourier Transform Infra Red Spectroscopy (FTIR), dan Powder X-Ray Diffraction (PXRD). Metode loading obat terdiri dari dua kategori, yakni penggabungan agen biomedis secara langsung dan loading secara post synthesis. Sebelum MOFs diaplikasikan, perlu dilakukan aktivasi dan penempelan material obat. Pengujian lepas lambat dapat dijalankan pada beberapa kondisi seperti dalam Simulated Body Fluid (SBF), Phosphate Buffer Saline (PBS), Bovine Serum Albumin (BSA) maupun simulasi menggunakan Grand Canonical Monte Carlo (GCMC). Pengujian secara in vivo dan in vitro juga dapat dilakukan untuk mengetahui dampaknya pada tubuh makhluk hidup dan aktivitasnya terhadap sel patogen. Kombinasi organik linker dan ion logam pusat yang berbeda akan menghasilkan ukuran pori, fleksibilitas, kapasitas loading, profil pelepasan obat, toksisitas, dan kemampuan menginhibisi yang berbeda pula. Pada review kali ini akan dibahas tentang kajian singkat terkait struktur dan desain MOFs, bio-MOFs, nano bio MOFs, strategi sintesis, dan strategi loading dan pelepasan obat untuk aplikasi dalam biomedis. Selanjutnya akan diberikan beberapa contoh aplikasi yang sudah dilakukan sejauh ini misalnya beberapa jenis MOFs yang sudah dienkapsulasi dengan beberapa material obat, seperti 5-fluoracil, ibuprofen, doxorubicin, dan dikaji waktu pelepasannya dan interaksinya dengan permodelan komputasi.Study of Metal–Organic Frameworks (MOFs) as a Novel Material for Drug Delivery. Metal–Organic Frameworks (MOFs) are a novel class of porous material that has wide potential applications including in drug delivery and slow release. Its flexible structure, regular crystalline pore size, and various coordination sites are some of the advantages of supporting MOFs properties in the encapsulation of various drugs. Various methods can be used for the MOFs synthesis include nanoprecipitation, solvothermal, reverse micro emulsion, and surfactant-templated solvothermal. Both characterization for synthesized materials and profile after encapsulation can be done using Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Differential Scanning Calorimetry (DSC), Fourier Transform Infra-Red Spectroscopy (FTIR), and Powder X-Ray Diffraction (PXRD). The drug loading method consists of two categories, namely the direct incorporation of biomedical agents and post-synthesis method. Before MOFs are applied in biomedical application, activation and attachment of medicinal materials should be performed. Meanwhile, for slow release testing can be run on several conditions such as in Simulated Body Fluid (SBF), Phosphate Buffer Saline (PBS), Bovine Serum Albumin (BSA) and simulation using Grand Canonical Monte Carlo (GCMC). In vivo and in vitro testing can also be done to determine the impact on the body of living creatures and their activity on pathogen cells. Different organic linker and metal center combinations will result in pore size, flexibility, loading capacity, drug release profiles, toxicity, and different inhibiting ability. Herein, we will discuss a brief review of the structure and design of MOFs, bio-MOFs, nano-bio MOFs, synthesis, drug loading and release strategies for applications in biomedicine. Furthermore, there will be some examples of applications that have been done so far, e.g. some types of MOFs that have been encapsulated with some medicinal materials, such as 5-fluorouracil, ibuprofen, doxorubicin, and reviewed its release time and interaction with computational modeling.
Karakterisasi dan Uji Efektivitas Allophane-Like untuk Adsorpsi Ion Logam Tembaga (Cu) Pranoto Pranoto; Tri Martini; Deta Agustin Rachmawati
ALCHEMY Jurnal Penelitian Kimia Vol 14, No 2 (2018): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.14.2.18538.202-218

Abstract

Telah dilakukan penelitian karakterisasi dan uji efektivitas allophane-like untuk adsorpsi ion logam tembaga (Cu). Allophane-like dibuat dengan mencampurkan larutan Tetraethyl Orthosilicate (TEOS) dan Aluminum Nitrate Nonahydrate [Al(NO3)3.9H2O] dengan perbandingan 0,5; 0,75; 1; 1,25 dan 1,5. Proses pencampuran dilakukan penambahan NaOH secara bertahap dan dilakukan pengadukan serta pemanasan. Penambahan NaOH dilakukan dengan membuat perbandingan NaOH dan Campuran TEOS dan Al(NO3)3.9H2O 3:1. pH campuran larutan yang diperoleh diukur dan pH larutan dibuat menjadi asam (pH 3-4). Allophane-like dikarakterisasi dengan spektroskopi infra merah (FTIR), XRD, keasaman, dan luas permukaan. Uji adsorpsi terhadap ion logam tembaga (Cu) dilakukan pada variasi perbandingan TEOS dan Al(NO3)3.9H2O 0,5; 0,75; 1; 1,25 dan 1,5, pH larutan tembaga (Cu) 3-7 serta waktu kontak 30-120 menit dengan sistem batch. Hasil penelitian diketahui bahwa allophane-like memiliki gugus fungsi yang sama dengan allophane-alam yang ditunjukkan dengan data FTIR yaitu memiliki puncak yang sama pada 3431-3252; 1631; 1071; 785; dan 562-457 cm-1. Hasil analisa XRD, keasaman dan luas permukaan menunjukkan karakteristik yang berbeda. Kondisi adsorpsi ion logam tembaga (Cu) terjadi pada variasi perbandingan TEOS dan Al(NO3)3.9H2O 1,5, pH 6, waktu kontak 120 menit, persentase penyerapan 41,79% dan kapasitas adsorpsi 0,97865 mg/g.Characterization and Effectivity of Allophane-Like in the Adsorption of Metal Ion of Copper (Cu). The characterization and effectivity testing of allophane-like for adsorption copper (Cu) metal ion has been studied. Allophane-like was prepared by mixing a solution of Tetraethylorthosilicate (TEOS) and Aluminum Nitrate nonahydrate [Al(NO3)3.9H2O] using ratio of 0.5; 0.75; 1; 1.25 and 1.5. The mixing process was done gradually adding NaOH and stirring and heating. The addition of NaOH was done by making a comparison between NaOH and mixture of TEOS dan Al(NO3)3.9H2O in 3:1. The pH of the mixture solution was measured and made acidic solution (pH 3-4). Allophane-like was characterized by infrared spectroscopy (FTIR), XRD, acidity, and surface area. The adsorption evaluation of copper (Cu) metal ion was done on the variation of the composition of TEOS dan Al(NO3)3.9H2O in 0.5; 0.75; 1; 1.25 and 1.5, the pH of a solution of copper (Cu) 3-7 and contact time of 30-120 minutes in batch system. The results revealed that the allophane-like has the same functional group with nature allophane indicated by the FTIR data that has the same peak at 3431-3252; 1631; 1071; 785; and 562-457 cm-1. XRD analysis results, acidity and surface area showed different characteristics. The best conditions adsorption of copper (Cu) metal ion occured at the composition of TEOS dan Al(NO3)3.9H2O in 1.5, pH 6, the contact time of 120 minutes, the absorption percentage of 41.79% and adsorption capacity of 0.97865 mg/g.
High Performance Liquid Chromatography Method Validation Of α-Mangostin Assay in Mangosteen (Garcinia mangostana L.) Fruit Rind Extract Formulated in Oral Solution Liliek Nurhidayati; Siti Sofiah; Ros Sumarny; Kevin Caesar
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 1 (2015): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.1.104.38-46

Abstract

Mangosteen fruit rind extract contain a lot of antioxidants. α-Mangostin is a component in mangosteen fruit rind that has highest antioxidant effect. The oral solution containing mangosteen fruit rind extract is required an assay method for quality assessment. Determination of a very low concentration of analyte in sample with very complex matrix, such as α-mangostin in oral solution, needs a selective and sensitive method, such as high performance liquid chromatography (HPLC). In this study, α-mangostin assay was performed by reverse phase HPLC system using octadecylsilane (C18) as stationary phase,  methanol-water (90:10) as mobile phase, the flow rate is 1.0 mL/min, and the UV detector at 316 nm. The retention time of α-mangostin was 9.622 minutes. Peak of α-mangostin was well separated with resolution of 1.725. Linearity was in the range of 1.67-5.01 ppm with correlation coefficient of 0.9986. The relative standard deviation (RSD) was 1.30 %, the recovery was in the range of 95.80-100.76 

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