Alchemy: Jurnal Penelitian Kimia最新文献

{"title":"Penerapan Desain Eksperimen Plackett-Burman dan Box-Behnken pada Analisis Voltametri Pulsa Diferensial untuk Penentuan Kadar Senyawa Kompleks Gd-DTPA","authors":"Santhy Wyantuti, Ravenna Aristantia, Y. Hartati, Husein H. Bahti","doi":"10.20961/alchemy.16.1.35166.140-151","DOIUrl":"https://doi.org/10.20961/alchemy.16.1.35166.140-151","url":null,"abstract":"Gadolinium merupakan salah satu golongan unsur tanah jarang yang menarik karena memiliki sifat paramagnetik yang tinggi. Pengkhelatan gadolinium dengan ligan dietilentriaminpentaasetat (DTPA) menghasilkan senyawa yang berguna dalam bidang kesehatan. Tujuan dari penelitian ini adalah menentukan kandungan unsur tanah jarang gadolinium sebagai kompleks dengan ligan DTPA secara voltametri pulsa diferensial dengan penerapan desain eksperimen Plackett-Burman dan Box-Behnken . Desain eksperimen Plackett-Burman digunakan untuk menyeleksi parameter yang memiliki relevansi positif terhadap respon arus. Parameter yang terpilih kemudian dioptimasi melalui desain eksperimen Box-Behnken sehingga diperoleh kondisi optimum tiap parameter. Parameter yang terseleksi meliputi konsentrasi ligan DTPA, waktu deposisi dan waktu kesetimbangan dengan nilai tiap parameter pada kondisi optimum masing-masing yaitu 150, 13 mgL -1 , 60 detik dan 30 detik.  Berdasarkan hasil pengukuran pada kondisi optimum didapat nilai presisi dan akurasi untuk kompleks Gd-DTPA yaitu 99,79% dan 93,42% dengan nilai limit deteksi dan kuantisasi untuk kompleks Gd-DTPA yaitu 3,97 mg/L dan 10,71 mg/L. The Application of Experimental Designs of Plackett-Burman and Box-Behnken in Differential Pulse Voltammetry Analysis for Gd-DTPA Complex Detection. Gadolinium is one of rare earth elements that is interesting because it has high paramagnetic properties. The gadolinium chelating with diethylentriaminpentaacetic acid (DTPA) ligands produces useful compounds in the health field. The purpose of this experiment is to determine amount of gadolinium as complex with DTPA on differential pulse voltammetry by applying Plackett-Burman and Box-Behnken experimental design. The method employed experimental design of Plackett-Burman to select factors, which have positive relevance to response. The selected factors are optimized based on experimental design of Box-Behnken to obtain the optimum condition each factors. The selected factors are ligand concentration, deposition time and equilibrium time with optimum value of 150 mgL -1 , 60 s and 30 s, respectively. Based on the result of measurement at optimum condition, the precision and accuracy value for Gd-DTPA complex is 99.79% and 93.42% with detection and quantization limit value for Gd-DTPA complex is 3.97 mg/L and 10.71 mg/L.","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"38 1","pages":"140-151"},"PeriodicalIF":0.0,"publicationDate":"2020-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73394422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Uji Efektivitas dan Karakterisasi Komposit Tanah Andisol/Arang Tempurung Kelapa Untuk Adsorpsi Logam Berat Besi (Fe)","authors":"P. Pranoto, Tri Martini, Winda Maharditya","doi":"10.20961/alchemy.16.1.33286.50-65","DOIUrl":"https://doi.org/10.20961/alchemy.16.1.33286.50-65","url":null,"abstract":"Penelitian ini untuk mengetahui kapasitas adsorpsi komposit tanah andisol/arang tempurung kelapa sebagai adsorben logam berat besi (Fe) berdasarkan pada kondisi komposisi, pH dan waktu kontak yang optimum. Tanah andisol diaktivasi dengan larutan NaOH 3 M dan arang tempurung kelapa diaktivasi menggunakan larutan HCl 4 M. Komposit tanah andisol/arang tempurung kelapa dibuat dengan mencampurkan tanah andisol dan arang tempurung kelapa pada variasi komposisi 100:0, 75:25, 50:50, 25:75 dan 0:100 (b/b) Uji adsorpsi terhadap logam besi (Fe) dilakukan pada variasi pH larutan 1, 2, 3, 4, 5 dan 6 serta waktu kontak 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, dan 60 menit dengan sistem batch. Pengukuran konsentrasi akhir pada saat kesetimbangan dilakukan dengan menggunakan Atomic Absorption Spectroscopy (AAS).  Hasil karakterisasi adanya proses aktivasi dan pengompositan ditunjukkan pada spektra Fourier Transform Infra Red (FTIR) yang mengalami pergeseran bilangan gelombang. Karakterisasi pola difraksi X-Ray Diffraction (XRD) yang menunjukkan adanya puncak baru. Hasil analisis Scanning Electron Microscope (SEM) komposit menunjukkan bahwa permukaan adsorben telah ditutupi logam besi (Fe). Pembentukan komposit juga menunjukkan adanya peningkatan luas permukaan dan nilai keasaman komposit. Berdasarkan penelitian ini diperoleh bahwa proses adsorpsi terjadi pada kondisi optimum komposisi komposit tanah andisol/arang tempurung kelapa 75:25 (b/b), pH larutan besi (Fe) 5 dan waktu kontak selama 30 menit dengan kapasitas adsorpsi sebesar 0,54 mg/g dan presentase adsorpsi 91,57%. Isoterm adsorpsi mengikuti isoterm Freundlich dengan nilai R2 sebesar 0,9456.Effectiveness Test and Characterization of Andisol Soil/Coconut Shell Charcoal for Adsorption of Iron (Fe). This research aims to determine the adsorption capacity composite of andisol soil and coconut shell charcoal as the adsorbent of iron (Fe) metal based on the composition condition, pH, and optimum contact time. Andisol soil was activated with NaOH 3 M solution, and coconut shell charcoal was activated with HCl 4 M solution. The composites were made under various composition of andisol soil/coconut shell charcoal of 100:0, 75:25, 50:50, 25:75 and 0:100 (w/w). The adsorption test was done on the pH variation of 1, 2, 3, 4, 5, 6 and used the contact time variation of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 and 60 minutes in a batch method. The concentration analysis of iron (Fe) metal was done by atomic absorption spectroscopy (AAS). The characterization result of the activation process can be shown on the Fourier transform infrared (FTIR) spectra with the shifting peak. Characterization of X-ray diffraction (XRD) diffractogram showed the emergence of a new peak in andisol soil and coconut shell charcoal. The result of scanning electron microscope (SEM) characterization analysis showed that the surface of the adsorbent was covered in iron. The composite formation also showed an increase in surface area and composite aci","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78623427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimasi dan Validasi Metode Penentuan Kadar Asam Glikolat dan Asam Laktat Dalam Krim Menggunakan Kromatografi Cair Kinerja Tinggi","authors":"Devi Wulandari, Gusrizal Gusrizal, T. A. Zaharah","doi":"10.20961/alchemy.16.1.34008.10-24","DOIUrl":"https://doi.org/10.20961/alchemy.16.1.34008.10-24","url":null,"abstract":"Telah dilakukan optimasi dan validasi metode penentuan asam glikolat dan asam laktat dalam krim menggunakan kromatografi cair kinerja tinggi. Pemisahan asam glikolat dan asam laktat dilakukan pada kolom fasa balik C-8menggunakan fasa gerak asam ortofosfat 0,1% dengan pH 3,5 dan detektor UV-Visible . Standar asam glikolat dan asam laktat dibuat dengan melarutkannya menggunakan asam ortofosfat 0,1% pH 3,5. Hasil eksperimen menunjukkan bahwa pada rentang konsentrasi 25 – 400 μg/mL, asam glikolat dan asam laktat memiliki kurva yang linear dengan koefisien korelasi masing-masing 0,9997 dan 0,9999. Uji presisi untuk larutan standar berkonsentrasi 100 µg/mL menghasilkan simpangan baku relatif sebesar 1,49% untuk asam glikolat dan 1,72% untuk asam laktat. Metode yang telah dioptimasi memberikan akurasi yang baik yang ditunjukkan oleh nilai perolehan kembali dari pengukuran tiga spiked sample dengan konsentrasi berbeda (50, 100, dan 150 μg/mL). Nilai perolehan kembali untuk masing-masing konsentrasi spiked sample adalah 97,12% ± 0,69; 98,76% ± 0,43; 100,80% ± 0,29 untuk asam glikolat dan 97,58% ± 0,39; 96,20% ± 0,68; 98,00% ± 0,38 untuk asam laktat. Batas deteksi dan batas kuantisasi untuk asam glikolat adalah 0,05 dan 0,17 μg/mL, sedangkan untuk asam laktat adalah 1,40 dan 4,67 μg/mL. Nilai kekasaran metode untuk asam glikolat pada hari pertama dan hari kedua adalah 1,43% dan 1,67%, sedangkan untuk asam laktat adalah 1,67% dan 1,25%. Metode yang telah dioptimasi dan divalidasi berpotensi untuk digunakan secara spesifik pada penentuan kadar asam glikolat dan asam laktat dalam krim. Optimization and Validation of Determination Methods of Glycolic Acid and Lactic Acid in Cream Using High-Performance Liquid Chromatography. A high-performance liquid chromatography analytical method for the determination of glycolic acid and lactic acid in creams has been optimized and validated. The separation was performed in a reverse phase C–8 column with a mobile phase of 0.1%, orthophosphoric acid at pH 3.5, and UV-Visible detector. The standard of glycolic acid and lactic acid was dissolved in 0.1% orthophosphoric acid at pH 3.5. The experimental results showed that in the concentration range of 25–400 μg/mL, glycolic acid and lactic acid showed a linear curve with a correlation coefficient of 0.9997 and 0.9999, respectively. The precision test for standard solutions containing 100 µg/mL resulted in a relative standard deviation of 1.49% for glycolic acid and 1.72% for lactic acid. The optimized method provided good accuracy indicated by the recovery of the measurement of three spiked samples in different concentrations (50, 100, and 150 μg/mL). The recovery for each concentration of the spiked sample was 97.12% ± 0.69; 98.76% ± 0.43; 100.80% ± 0.29 for glycolic acid and 97.58% ± 0.39; 96.20% ± 0.68; 98.00% ± 0.38 for lactic acid. The limit of detection and limit of quantization for glycolic acid was 0.05 and 0.17 μg/mL, and for lactic acid was 1.40 and 4.67 μg/mL. The ","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"47 1","pages":"10-24"},"PeriodicalIF":0.0,"publicationDate":"2020-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88535733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enkapsulasi dan Karakterisasi Pelepasan Terkendali Pupuk NPK Menggunakan Kitosan Yang Ditaut Silang Dengan Glutaraldehida","authors":"J. Jayanudin, R. S. Lestari","doi":"10.20961/alchemy.16.1.34711.110-125","DOIUrl":"https://doi.org/10.20961/alchemy.16.1.34711.110-125","url":null,"abstract":"Pelepasan terkendali pupuk NPK bertujuan untuk meningkatkan efisiensi penggunaan unsur hara tanaman dan juga untuk mengurangi pencemaran lingkungan. Penelitian ini bertujuan untuk menentukan pengaruh konsentrasi larutan kitosan dan glutaraldehida terhadap yield dan daya serap mikrokapsul pupuk NPK. Tujuan lain adalah menentukan karakterisasi dan analisis release pupuk NPK dari mikrokapsul dan juga menghitung kinetika release . Mikrokapsul pupuk NPK dipreparasi dengan mencampurkan pupuk NPK cair ke dalam larutan kitosan, kemudian campuran tersebutkan diteteskan ke dalam larutan glutaraldehida sambil diaduk. Mikrokapsul pupuk NPK yang terbentuk dicuci menggunakan petroleum eter dilanjutkan dengan heksana dan dikeringkan. Hasil penelitian menunjukkan bahwa peningkatan konsentrasi larutan kitosan dan glutaraldehida menghasilkan peningkatan yield, menurunkan daya serap air, dan menurunkan pupuk NPK yang release dari mikrokapsul pupuk NPK. Model kinetika release yang sesuai berdasarkan tingginya nilai R 2 adalah model order satu dan model Higuchi didapat dari mikrokapsul pupuk NPK yang dipreparasi dengan 1% (b/v) larutan kitosan dan 5% (v/v) larutan glutaraldehida.  Encapsulation and Characterization of Controlled Release of NPK Fertilizer Using Glutaraldehyde-Crosslinked Chitosan. Controlled release NPK fertilizer aims to improve the nutrient use efficiency (NUE) of plants and also to reduce environmental pollution. This study aims to determine the effect of the concentration of chitosan and glutaraldehyde solutions on the yield and absorptive ability of NPK fertilizer microcapsules. Another objective was to determine the characterization and analysis of NPK fertilizer releases from microcapsules and also to calculate the release kinetics. NPK fertilizer microcapsules were prepared by mixing liquid NPK fertilizer into a chitosan solution, and then the mixture was dripped into a glutaraldehyde solution while stirring.  NPK fertilizer microcapsules formed were washed using petroleum ether, followed by hexane and dried. The results showed that an increase in the concentration of chitosan and glutaraldehyde solutions resulted in an increase in yield, decreased water absorbency, and l ower NPK fertilizer released from microcapsules. The appropriate release kinetics models based on the higher R 2 value were the first-order model and the Higuchi model obtained from microcapsules of NPK fertilizer that was prepared with 1% (w/v) chitosan solution and 5% (v/v) glutaraldehyde solution.","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"2 1","pages":"110-125"},"PeriodicalIF":0.0,"publicationDate":"2020-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88749991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Senyawa Hidrazone dari Vanilin-DNPH Sebagai Sensor Kolorimetri Anion Sianida","authors":"S. Suharman, Siti Utari Rahayu","doi":"10.20961/alchemy.16.1.34635.77-93","DOIUrl":"https://doi.org/10.20961/alchemy.16.1.34635.77-93","url":null,"abstract":"Senyawa hidrazon ( E )-4-((2-(2,4- dinitrophenyl ) hydrazineylidene ) methyl )-2- methoxyphenol telah disintesis dari vanilin dan 2,4-dinitrofenilhidrazin (DNPH). Uji sensor anion dilakukan dengan menambahkan anion F - , Cl - , Br - , I - , CN - , SO 4 2- , CO 3 2- , CH 3 COO - dan H 2 PO 4 - dalam pelarut asetonitril. Uji limit deteksi reseptor  ( E )-4-((2-(2,4- dinitrophenyl ) hydrazineylidene ) methyl )-2- methoxyphenol terhadap anion sianida dilakukan dalam pelarut asetonitril. Hasil uji sensor anion menunjukan bahwa reseptor  selektif terhadap anion sianida dengan menghasilkan perubahan warna dari kuning ke merah. Hasil analisa dengan spektrofotometer UV-Vis reseptor memberikan perubahan panjang gelombang dari 395 nm menjadi 472 nm pada penambahan anion sianida. Reseptor ( E )-4-((2-(2,4- dinitrophenyl ) hydrazineylidene ) methyl )-2- methoxyphenol dapat mendeteksi anion CN- dengan limit deteksi sebesar 7 mM. A Hydrazone Compound from Vanillin-DNPH as Colorimetric Sensor of Cyanide Anion . A hydrazone compound ( E )-4-((2-(2,4-dinitrophenyl)hydrazineylidene)methyl)-2-methoxyphenol has been synthesized from vanillin and 2,4-dinitrophenylhydrazine (DNPH). The anion sensor study were done by adding Br - , CN - , F - , SO 4 2- , Cl - , I - , CO 3 2- , CH 3 COO - and H 2 PO 4 - anion in acetonitrile solvent. The detection limit study of receptor E )-4-((2-(2,4-dinitrophenyl)hydrazineylidene)methyl)-2-methoxyphenol for cyanide anion was carried out in acetonitrile.  The result of anion sensor study shows that the receptor was selective to cyanide anion by providing change of color from yellow to red. The analysis result using spectrophotometer ultraviolet-visible of the receptor provided change of maximum wavelength from 395 nm to 472 nm when the cyanide anion was added. Receptor ( E )-4-((2-(2,4-dinitrophenyl) hydrazineylidene)methyl)-2-methoxyphenol can detect CN - with limit of detection 7 mM.","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"2015 1","pages":"77-93"},"PeriodicalIF":0.0,"publicationDate":"2020-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87796942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengaruh Konsentrasi Asam Terhadap Sifat Fisik dan Muatan Permukaan Selulosa Termodifikasi","authors":"A. Pratama, B. Piluharto, D. Indarti, T. Haryati, H. S. Addy","doi":"10.20961/alchemy.15.2.33756.315-328","DOIUrl":"https://doi.org/10.20961/alchemy.15.2.33756.315-328","url":null,"abstract":"Selulosa merupakan salah satu biopolimer melimpah yang banyak digunakan dalam berbagai bidang seperti kertas, energi dan material komposit. Hidrofilisitas, dapat diperbaharui, ramah lingkungan dan aman adalah sifat-sifat selulosa yang dapat berpotensi menjadi material maju. Berdasarkan sifat-sifatnya, selulosa dapat dimodifikasi untuk menghasilkan sifat fungsional yang sesuai dengan aplikasinya. Dalam penelitian ini, selulosa mikrokristalin (MCC) dimodifikasi melalui metode hidrolisis asam. Prinsip metode ini adalah penghilangan bagian amorf pada selulosa oleh asam, meninggalkan bagian kristal. Selain itu, ketika asam digunakan sebagai agen hidrolisis, maka akan menghasilkan muatan permukaan pada selulosa. Dalam penelitian ini, pengaruh berbagai konsentrasi asam pada struktur kimia, kristalinitas, morfologi dan muatan permukaan telah dikaji. Perubahan struktur selulosa dianalisis menggunakan Fourier Transform Infra Red (FTIR), kristalinitas menggunakan X-ray Diffraction (XRD), morfologi menggunakan Scanning Electron Microscopy (SEM) dan muatan permukaan menggunakan titrasi konduktomteri. Hasil analisis FTIR menunjukkan masuknya gugus sulfat pada struktur selulosa. Analisis XRD menunjukkan peningkatan kristallinitas dalam selulosa termodifikasi seiring bertambahnya konsentrasi asam. Hasil analisis morfologi menunjukkan partikel dalam selulosa termodifikasi (CM) lebih tersebar daripada MCC. Analisis titrasi konduktometri menunjukkan bahwa mengalami peningkatan muatan permukaan pada CM seiring dengan bertambahnya konsentrasi asam. Oleh karena itu, dapat disimpulkan bahwa pengaruh konsentrasi asam sulfat pada hidrolisis selulosa memberikan dampak yang signifikan pada sifat fisik dan muatan permukaan.Effect of Acid Concentration on Physical Properties and Surface charge of Modified Cellulose. Cellulose is one of abundant biopolymer that many widely used in various applications such as paper, energy and composite material. Hydrophilicity, renewable, biodegradable, and safety are cellulose properties that can became potential of advance materials. In the utilization, cellulose can be modified its properties for different purposes. In this work, microcrystalline cellulose (MCC) was modified by acid hydrolysis method. The principle of this method is removed amorphous region of cellulose by acid and leaving crystalline phase. Moreover, when acid was used as hydrolyzing agent, it produce the surface charge on cellulose. In this research, the effect of various concentration of acid on the chemical structure, crystallinity, morphology and surface charge have studied. The chemical structures were analyzed using Fourier Transform Infra Red (FTIR), crystallinity using X-ray Diffraction (XRD), morphology using Scanning Electron Microscopy (SEM), and surface charge using titration conductometric. The FTIR analysis result has successfully showed the entry of sulfate groups on the cellulose structure. The XRD analysis showed increasing crystallinity in Cellulose Mod","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89844264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perbandingan Kandungan Senyawa Kimia dan Aktivitas Antibakteri terhadap MRSA (Methicillin-resistant Staphylococcus aureus) Beberapa Minyak Atsiri Daun Salam (Syzygium polyanthum)","authors":"Muhammad Salman Fareza, E. D. Utami, Elesenda May GIta, Vintya Roosalinda Permatasari, Tryandika Telaumbanua, Nur Amalia Choironi","doi":"10.20961/alchemy.15.2.25736.302-314","DOIUrl":"https://doi.org/10.20961/alchemy.15.2.25736.302-314","url":null,"abstract":"Daun Syzygium polyanthum secara tradisional telah digunakan untuk mengobati penyakit yang disebabkan oleh bakteri. Kandungan kimia dari minyak atsri dari suatu tanaman dipengaruhi oleh daerah asal tumbuhnya. Tujuan penelitian ini untuk mengetahui komponen minyak atsiri daun S. polyanthum dari Bekasi, Lembang, Purwokerto Baturaden dan Curup, serta aktivitas antibakterinya terhadap MRSA Minyak atsiri daun S. polyanthum diperoleh dengan metode destilasi uap. Kandungan komponen senyawa pada minyak atsiri dianalisis menggunakan GC-MS. Sifat antibakteri minyak atisri dievaluasi menggunakan metode difusi cakram pada rentang konsentrasi 12  ̶  100 ppm. Rendemen minyak atsiri daun S. polyanthum yang diperoleh dari Bekasi, Lembang, Purwokerto Baturaden dan Curup berturut-turut sebesar 0,03%; 0,06%; 0,072%; 0,120% dan 0,067%. Hasil analisis GC-MS komponen minyak atsiri daun S. polyanthum dari berbagai daerah tersebut memperlihatkan senyawa aldehid dan terpenoid sebagai komponen utama. Minyak atsiri daun S. polyanthum dari Bekasi, Purwokerto, Baturaden dan Curup dapat memberikan daya hambat terhadap MRSA sebesar 9,2  ̶  15,3 mm, sedangkan minyak atsiri dari Lembang tidak memberikan daya hambat. Minyak atsiri daun S. polyanthum daerah Baturaden memiliki aktivitas menghambat pertumbuhan bakteri MRSA lebih baik dibandingkan daerah lainnya yaitu 15,3 mm pada konsentrasi 100 ppm dengan kategori intermediet. Penelitian mengenai perbandingan komponen kimia dan sifat antibakteri MRSA minyak atsiri daun S. polyanthum dari berbagai daerah ini baru pertama kali dilaporkan.","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84815456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Temperature Effect on Ultrasonic-assisted of Synthesis Methyl Ferulate and Its Antiplatelet Assay","authors":"J. Ekowati, Rian Putra Pratama, K. A. Nofianti, N. Diyah","doi":"10.20961/alchemy.15.2.29914.272-286","DOIUrl":"https://doi.org/10.20961/alchemy.15.2.29914.272-286","url":null,"abstract":"Ferulic acid (FA) has been reported to have antiplatelet activity through indirectly inhibiting P2Y12 receptor. In order to increase the activity of FA, by improving its lipophilicity, so that it is easier to enter the cell, synthesis methyl ferulate was conducted through Fisher esterification. Ultrasonic waves were utilized as source of energy emitted through water as the medium at two various of temperature, i.e., 55 °C and 65 °C. The purposes of this study are to produce methyl ferulate and to determine the reaction constant rate (k) and its energy activation (Ea), at temperature of 55 °C and 65 °C. Moreover, the biological activity as antiplatelet was investigated at dose 20 mg/kg BW. The antiplatelet assay was conducted by clotting time and bleeding time methods. The results were analyzed by one way ANOVA program (P<0.05). The yield of methyl ferulate are 50.3% and 67.1% at 55 °C and 65 °C, respectively. The k value at 55°C is 4x10-5 cons-1min-1, while that of at 65 °C is 9x10-5 cons-1min-1. The clotting time and bleeding time of methyl ferulate obtained were 265 sec and 175 sec, respectively. The antiplatelet activity of methyl ferulate is better than ferulic acid.","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"294 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90645228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolasi Mikroselulosa dari Limbah Eceng Gondok (Eichornia crassipes) dengan Metode Bleaching-Alkalinasi","authors":"Jeesica Hermayanti Pratama, Rizka Lailatul Rohmah, Amalia Amalia, Teguh Endah Saraswati","doi":"10.20961/alchemy.15.2.30862.239-250","DOIUrl":"https://doi.org/10.20961/alchemy.15.2.30862.239-250","url":null,"abstract":"Isolasi selulosa dari tanaman Eceng Gondok (Eichornia crassipes) berhasil dilakukan dengan menggunakan metode bleaching diikuti dengan alkalinasi. Metode bleaching dilakukan menggunakan NaOCl dengan pengadukan dan pemanasan suhu rendah yaitu 80 oC selama 4 jam, diikuti dengan metode alkalinasi menggunakan NaOH dengan pemanasan pada suhu rendah yaitu 45 oC selama 3 jam. Penerapan metode bleaching dan alkalinasi ini bertujuan untuk delignifikasi dengan memutuskan rantai polimerik diantara selulosa dengan lignin atau hemiselulosa. Selain itu, proses oksidasi lanjut juga terjadi karena keberadaan HOCl dan OH- sebagai hasil peruraian NaOCl dan NaOH. Setelah pencucian hingga pH netral, hasil isolasi yang didapatkan adalah berupa serbuk putih yang secara fisis berbeda dari material awal sebelum perlakuan. Hasil rendemen berkisar 6 ─ 20% dengan penyusutan massa sebesar 80%. Analisa gugus fungsi hasil isolat dengan spektrometer Fourier Transform Infrared (FTIR) menunjukkan keberadaan serapan dari gugus hidroksil ─OH, ─C─H, =C─H, ─OH dan C=O (gugus karboksilat), C-H dan C─O, dan C─O─C pada cincin piranosa yang menguatkan keberhasilan isolasi selulosa. Berdasarkan observasi morfologi dan struktur dengan menggunakan scanning electron microscope (SEM), selulosa hasil isolasi berbentuk butiran kristal dengan ukuran mikrometer yang secara signifikan berbeda dari penampakan fisis serat awal sebelum perlakuan.Isolation of Cellulose Microfiber from Water Hyacinth (Eichornia crassipes) Waste by Bleaching-Alkalization Method. Cellulose isolation from water hyacinth plants (Eichornia crassipes) was successfully performed using bleaching followed by alkalization methods. The bleaching method was carried out using NaOCl with stirring dan heating at a low temperature of 80 oC for 4 hours. This method was then followed by an alkalization method using NaOH with heating at a low temperature of 45 oC for 3 hours. The application of the bleaching followed by alkalization method aimed to proceed the delignification by breaking the polymeric chain between cellulose dan lignin or hemicellulose. In addition, the process of advanced oxidation also occurred due to the presence of HOCl dan OH- decomposed from NaOCl dan NaOH. The solid was then washed until the pH of the solution was neutral. As results, the white powder solid was obtained which was physically different from the initial material before treatment. The yield obtained was around 6 ─ 20% with a mass shrinkage of 80%. Analysis of the functional groups of the isolates using Fourier Transform Infrared (FTIR) spectrometers showed the presence of the hydroxyl groups ─OH, ─C─H, =C─H, ─OH dan C=O (carboxylic groups), CH dan C ─O, dan C─O─C on the pyranose ring that reinforces the success of the cellulose isolation. Based on morphological dan structural observations under a scanning electron microscope (SEM), the cellulose isolated was in crystalline granules in micrometer size which was significantly different compared to the ","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"165 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76939683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sintesis Komposit Hidroksiapatit-Lantanum Oksida (HA-La2O3) dengan Metode Hidrotermal secara In-Situ dan Ex-Situ","authors":"G. S. Hutabarat, Dzikri T Qodir, H. Setiawan, Nur Akbar, A. R. Noviyanti","doi":"10.20961/alchemy.15.2.32062.287-301","DOIUrl":"https://doi.org/10.20961/alchemy.15.2.32062.287-301","url":null,"abstract":"Hidroksiapatit (HA) Ca10(PO4)6(OH)2 merupakan senyawa kalsium yang digunakan pada bidang ortopedi dan periodontal karena mineral ini merupakan penyusun utama dalam jaringan tulang dan gigi. Untuk dapat digunakan sebagai graft tulang dan tambal gigi, perlu dilakukan pengaturan kemurninan, kristalinitas dan ukurannya baik sebagai senyawa tunggal (HA) atau kompositnya. Pengaturan tersebut dapat dilakukan melalui proses sintesisnya. Pada penelitian ini HA disintesis dari CaO yang diisolasi dari cangkang telur ayam dengan metode kalsinasi pada suhu 1000 °C selama 5 jam, kemudian ditambahkan diammonium hidrogenfosfat. Sintesis komposit HA-La2O3 dilakukan dengan dua metode hidrotermal dengan dua cara berbeda, yaitu secara in-situ dan ex-situ. Pada sintesis HA dengan metode in-situ dilakukan pencampuran bahan dalam satu tahap yaitu CaO, diammonium hidrogenfosfat dan 5% b/b lantanum oksida dengan perbandingan mol Ca/P=1,67 secara hidrotermal pada 230 °C selama 48 jam. Sintesis HA dengan metode ex-situ dilakukan dengan dua tahap yaitu mencampur CaO dan diammonium hidrogenfosfat untuk membentuk HA. Setelah HA terbentuk kemudian dilakukan sintesis komposit dengan penambahan lantanum oksida. Komposisi bahan dan kondisi reaksi metode ex-situ dilakukan dengan cara yang sama seperti metode in-situ. Hasil XRD dan FTIR menunjukkan terbentuknya komposit HA-La2O3 dari kedua metode yang dilakukan. Namun kemurnian, kristalinitas dan ukuran komposit menunjukan hasil yang berbeda. Karakteristik komposit yang dihasilkan dari metode in-situ lebih baik dibandingkan dengan metode ex-situ.","PeriodicalId":7926,"journal":{"name":"Alchemy: Jurnal Penelitian Kimia","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76176703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}