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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.
Arjuna Subject : -
Articles 285 Documents
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Uji Aktivitas Antibakteri Ekstrak Sarang Lebah Hutan (Apis dorsata) terhadap Pertumbuhan Staphylococcus aureus, Escherichia coli dan Pseudomonas aeruginosa Ika Prestianti; Maswati Baharuddin; Sappewali Sappewali
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.14.2.13028.314-322

Abstract

Penyakit infeksi akibat bakteri merupakan masalah serius dalam kesehatan. Antibakteri alami yang dapat digunakan untuk menghambat pertumbuhan bakteri yaitu sarang lebah hutan (Apis dorsata) terdiri propolis, kantong madu, kantong telur dan kantong pollen yang mengandung senyawa metabolit sekunder seperti flavonoid, tanin dan asam fenolat. Tujuan dari penelitian ini adalah megetahui aktivitas antibakteri ekstrak sarang lebah hutan dari setiap pelarut yang digunakan dan untuk mengetahui pengaruh konsentrasi ekstrak sarang lebah hutan terhadap pertumbuhan bakteri Staphylococcus aureus, Escherichia coli dan Pseudomonas aeruginosa. Pengujian antibakteri dilakukan dengan metode difusi kertas cakram dengan lama perendaman 1 jam kemudian diinkubasi selama 3 x 24 jam. Hasil penelitian menunjukkan bahwa aktivitas antibakteri ekstrak metanol sarang lebah memiliki aktivitas tertinggi pada bakteri  E. coli yaitu 3,8 mm pada konsentrasi 8%, ekstrak etil asetat sarang lebah pada bakteri S. aureus yaitu 3,72 mm pada konsentrasi 8% dan ekstrak n-heksan sarang lebah pada bakteri E. coli yaitu 16,1 mm pada konsentrasi 8%. Pengaruh konsentrasi ekstrak yaitu semakin tinggi konsentrasi maka semakin besar pula daya hambat ekstrak terhadap pertumbuhan bakteri S. aureus, E. coli dan P. aeruginosa.Antibacterial Evaluation of Extract Beehive (Apis dorsata) against Growth of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Bacterial infectious diseases are serious health problems. A natural antibacterial that can be used to inhibit bacterial growth of honeycomb (propolis, honey bag, egg bag and pollen bag) containing secondary metabolite compounds such as flavonoids, tannins and phenolic acids. The purpose of this research is to know the antibacterial activity of honeycomb extract from each solvent used and to know the effect of honeycomb extract concentration against the bacteria growth of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Antibacterial testing was performed by the method of paper disc diffusion with soaking time 1 hour followed by incubation for 3 x 24 hours. The results show that antibacterial activity of methanol honeycomb extract had the highest activity in E. coli bacteria of 3.8 mm at 8% concentration, followed by those of ethyl acetate honeycomb extract and n-hexan honeycomb extract which have antibacterial activity of 3.72 mm and 16,1 mm at 8% concentration against S. aureus and E. coli, respectively. The effect of extract concentration is the higher the concentration the greater the inhibitory power of extract against the bacteria growth of S. aureus, E. coli and P. aeruginosa.
Effect of Tannase on Chemical Parameters of Cashew Apple Juice (Anacardium occidentale Linn) Yunita Arian Sari Anwar
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.11.1.103.29-37

Abstract

We previously produced tannase from Aspergillus niger using solid state medium. In the present study the enzyme used cashew apple juice. The aim this research was to know effect of tannase on chemical parameters of cashew apple juice. The concentration of tannase used was 0%; 0.02%; 0.04%; 0.06%; 0.08% and 0.1% (v/v). The chemical properties of the juice produced by enzymatic method were compared with the juiced produced through high temperature treatment (100oC).  This research showed that the addition of 0.1% of tannase enzyme provide the best product according to the lower content of tannins than the content of tannins in the juice produced with high temperature treatment. The tannase treatment did not change the vitamin C content, content of protein and pH. Meanwhile, high temperature treatment decreased the content of vitamin C and protein.
Synthesis and Dielectric Properties of Four-Layered Aurivillius SrBi4Ti4O15 Doped Nd3+ and Mn4+ Sestry Misfadhila; Evi Adhelina; Yestria Rilda; Syukri Arief; Zulhadjri Zulhadjri
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.11.2.714.127-134

Abstract

Synthesis of four-layered Aurivillius compound doped with Nd3+ and Mn4+ cations, SrBi3.5Nd0.5Ti4-xMnxO15 (x = 0; 0.5; 1) was carried out using molten salt method with a mixture of Na2SO4/K2SO4 as a flux. The synthesized products were characterized using X-ray diffraction (XRD) and refined by Le Bail technique. The results of XRD analysis show that the four-layered Aurivillius compound formed, however there are additional peaks identified as perovskite and Bi7.68Ti0.32O12.16  phases for x = 0 and perovskite and Sr4Ti3O10phases for x = 0.5 and 1. The results of refinement show that four-layered Aurivillius phase formed has orthorhombic symmetry with A21am space group. Scanning Electron Microscopy (SEM) shows the plate like morphology that are characteristic of Aurivillius compound. Dielectric constant of the samples show increasing value as increasing of Mn4+ concentration.
ASSESSING THE CHEMICAL PROPERTIES OF DAMMAR ASPHALT USING FOURIER TRANSFORM INFRARED SPECTROSCOPY Ary Setyawan; M Fachri; A Sumarsono
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 1 (2016): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.1.950.95-102

Abstract

Dammar Asphalt (Daspal) is expected to be used as a bio-asphalt renewable binder for road construction. It is made with a modification of the "Jabung", which is the dammar gum based material mixed with grounded red brick debris and low quality cooking oil at a certain ratio. Dammar gum is obtained from the Dipterocarpaceae family of trees in India and East Asia, most are produced by tapping trees. The gum varies in color from clear to pale yellow. Dammar gum is a triterpenoid resin, containing a large number of triterpenes and their oxidation products. Many of them are low molecular weight compounds. The objective of this research is to analyze the chemical properties of Daspal uses a Resonance Fourier Transform Infrared Spectroscopy (FTIR) method to compare with conventional asphalt. The investigation using spectral data showed that all types of Daspal have similar functional groups of Saturate, Aromatic, Resins, and Asphalten as the 60/70 penetration conventional bitumen, so that based on its chemical properties Daspal can be considered as bioaspal.
SOLVENT FREE SYNTHESIS OF CHALCONE AS ANTIBACTERIAL SUBSTANCE Susy Yunita Prabawati; Arifah Khusnuryani; Khamidinal Khamidinal
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.13.1.4324.95-102

Abstract

The aims of this study was to synthesize a compound of 3-methoxy-4-hydroxychalcone through Claisen-Schmidt condensation with grinding technique (solvent-free). Vanillin, acetophenone and 60 % NaOH catalyst used in this synthesis. Characterization of products was done with a spectrophotometer FTIR and 1H-NMR spectrometer. The  product was obtained as a orange solid which has a melting point at    58 - 59 ˚C. Identification of the product by IR spectrophotometer showed the absorption of  C=C in the wavenumber of 1496.76 cm-1 which confirmed that the hydration reaction of chalcone had occurred. Analysis using 1H-NMR spectrometer also showed the proton of the CH=CH appearing on chemical shift (δ) 7.99 ppm. The antibacterial activity test showed that the compounds of 3-methoxy-4- hydroxychalcone has a potential as an antibacterial against bacteria E. coli and B. subtilis.
TRANSFORMATION OF ETHYL-P-METHOXYCINNAMATE TO P –METHOXYCINNAMIC ACID FROM KENCUR (Kaempheria galanga L.) AND THEIR ANTIBACTERIAL ACTIVITY Muhamad Salman Fareza; Rehana Rehana; Nuryanti Nuryanti; Didin Mujahidin
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.13.2.8472.176-190

Abstract

This study aimed to evaluate the antibacterial properties of ethyl-p-methoxycinnamate and p-methoxycinnamate acid from Kaempheria galanga L. Ethyl-p-methoxycinnamate was isolated from the n-hexane rhizome extract of Kaempheria galanga L. Separation and purification of this compound was carried out with vacuum liquid chromatography and column chromatography. Hydrolysis of ethyl-p-methoxycinnamic under alkaline conditions obtained p-methoxycinnamic acid with a good yield of 85 %. The structure of the compounds were charactrized with IR, NMR spectrophotometer (1H-NMR and 13C-NMR) and mass spectrophotometer. The antibacterial properties of the compounds were evaluated using microdilution methods against B. cereus ATCC 11778, L. monocytogenes ATCC 7644, E. coli ATCC 25922, S. enterica sv Typhimurium ATCC 14028, and E. aerogenes ATCC 13048. The compounds showed weak antibacterial properties. Only ethyl p-methoxycinnamate showed the strongest antibacterial activity, especially against B. cereus ATCC 11778 bacteria with MIC values of 62.5 mg /mL. The change of the functional groups provided no significant impact on the antibacterial activity.
Aktivitas Antibakteri dan Antioksidan Asam Galat dari Kulit Buah Lokal yang Diproduksi dengan Tanase Eka Junaidi; Yunita Arian Sani Anwar
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.14.1.11300.131-142

Abstract

Penelitian ini mempelajari tentang produksi asam galat menggunakan enzim tanase dari limbah kulit buah lokal di Lombok. Limbah kulit buah lokal yang digunakan yaitu kulit buah kepundung (Baccaurea racemosa Muell.Arg), kulit buah juwet (Syzygium cumini), dan kulit buah manggis (Garcinia mangostana). Pada penelitian ini dilakukan pengujian asam galat yang dihasilkan, untuk mengetahui aktivitas antioksidan dan antibakteri. Pengujian sifat antioksidan dilakukan dengan menggunakan metode DPPH, sedangkan aktivitas antibakteri diuji dengan menggunakan metode difusi agar pada bakteri Escherichia coli dan Staphylococcus aureus. Hasil penelitian menunjukkan bahwa asam galat dari ketiga kulit buah memiliki aktivitas antioksidan. Asam galat dari kulit buah kepundung, kulit buah juwet dan kulit buah manggis memiliki IC50 masing-masing sebesar 5.95; 5,96; dan 5,92 ppm. Berbeda dengan kemampuan sebagai antioksidan, asam galat resistan terhadap bakteri Escherichia coli dan Staphylococcus aureus yang menunjukkan bahwa asam galat tidak memiliki aktivitas sebagai antibakteri.Antibacterial and Antioxidant Activity of Gallic Acid Extracted from Local Fruit Peels Produced by Tannase. This research studied the gallic acid production using tannase enzym from fruit local peels in Lombok. The local fruit waste used are kepundung rind (Baccaurea racemosa Muell.Arg), juwet rind (Syzygium cumini) and mangosteen rind (Garcinia mangostana). The produced Gallic acid was tested to determine its antioxidant and antibacterial activity. The antioxidant test conducted by DPPH method, meanwhile, the antibacterial activity was performed by agar diffusion method against bacteria Escherichia coli and Staphylococcus aureus. The results showed that the produce gallic acid from those three rind provide antioxidant activity. Gallic acid from kepundung rind, juwet rind, and mangosteen rind have IC50 values of 5,95; 5,96; and 5,92, respectively. Gallic acid does not showed inhibitory actions against the growth of Escherichia coli and Staphylococcus aureus. This result showed that gallic acid from local fruit waste provided no an antibacterial activity.
Composite of Chitosan Vanilin / Sulfonated Polystyrene As Polymer Electrolyte Membranes: Cationic Exchange Capacity, Swelling Degree And Thermal Properties Edi Pramono; Candra Purnawan; Yuniawan Hidayat; Jati Wulansari; Sayekti Wahyuningsih
ALCHEMY Jurnal Penelitian Kimia Vol 10, No 2 (2014): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.10.2.55.116-129

Abstract

Research on the preparation and characterization of sulfonated polystyrene (PST) /chitosan vanillin (KV) composite as electrolyte membranes has been conducted in order to investigate the effect of PST and KV composition  to its chemical and physical properties. Polystyrene was modified by sulfonation reaction to produces PST, meanwhile chitosan was modified by schift base reaction to produces KV. The composite membranes were prepared by casting method and were characterized in order to identify the functional groups contained in the composite, the cation exchange capacity (CEC), the Swelling Degree (SD), the thermal properties and the morphology. The peak of imine vibration in the FTIR spectrum indicates that the chitosan vanilin was succesfully synthesized. Meanwhile, the peak of sulfonate vibration indicates the product of sulfonation on polystyrene. The result of CEC analysis shows that the addition of sulfonate groups on polystyrene and the addition of phenolic groups on chitosan increase the CEC value. The increasing of PST and KV concentration in membrane enhance the CEC value. However, the increasing of PST concentration in membrane composition even decrease the Swelling Degree of membranes. Meanwhile, the increasing of KV concentration increase the swelling degree of membranes. Thermal analysis shows that the thermal decomposition of membranes occurs in three stages i.e. the dehydration of water molecules, the degradation of the subtituen groups and the plasticizer and the degradation of the back bone of chitosan and polystyrene.
Lift Off Process on Fabrication of Carbon Monoxide (CO) Gas Sensor Devices Slamet Widodo; Goib Wiranto
ALCHEMY Jurnal Penelitian Kimia Vol 10, No 2 (2014): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.10.2.540.173-185

Abstract

This paper  discuss  the design and fabrication of microdevice to be used  as platform for  CO (Carbon monoxide)  gas sensor based on tin dioxide (SnO2). The device has been designed on silicon substrate with an active area of 3x3 mm2, and  it is consist of  bonding pad, heater, electrode, and temperature sensor components. The minimum feature size  used is 50 microns, as allowed by the capability of photolithographic process. The formation of microdevice structure  was carried out by  lift-off  technique on platinum (Pt) layer, which was deposited by DC sputtering with aluminum (Al) as sacrificial layer. The overall chip dimension is 5x5 mm2. The measurement  that was  conducted to study the  characteristic of resistance  asfunction  of  temperature  has  shown   that  the  heater  and  temperature  sensor elements  could  work  as  expected,  in  which  their  resistances  change  linearly  as  the temperature of the substrate increase by  20–200  °C. The  resistance values of the heater increase  500–1000  ohm.  Meanwhile,  the  resistance  increasing  for  temperatur  sensor  is between  100–300 ohm. 
MODIFICATION OF SCREEN PRINTED CARBON ELECTRODEBY POLYPYRROLE FOR DETERMINATION OF HYDROQUINONE Khoirul Ngibad; Ani Mulyasuryani; Diah Mardiana
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 1 (2016): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.1.938.36-49

Abstract

Electropolymerization of polypyrrole for determination of hydroquinone on screen printed carbon electrode (SPCE) was performed using cyclic voltammetry. Electropolymerization of polypyrrole on SPCE begins with determining the optimum conditions of cyclic voltammetry (working potential, scan rate, number of cycles) and the conditions of solution (pyrrole and KCl concentrations).The working potential were varied at 0 – 0.8; 0 – 0.9; 0 – 1 V. The variation of scan rate were 50, 100, 150 mV/s and number of cycleswere 5, 10,15 cycles. The influence of pyrrole concentration was studied by providing variation of 5, 50, 100 mM. Meanwhile, the KCl concentration were at 0.1; 0.5; 1 M. The SPCE modified with polypyrrole was washed with deionized water and was dried at room temperature. The prepared polypyrrole was analyzed and based on the high anodic and cathodic peak current of the hydroquinone, it is confirmed that the preparation was succefully conducted. The optimum conditions on electropolymerization of polypyrrole areat the working potential of 0 – 0.9 V; the scan rate 100 of mV/s; the number of cyclesis 10, and at thepyrroleconcentration of 50 mM and KCl concentration of 0.5 M. SPCE modified polypyrrole can determine the hydroquinone at the concentration range of 5 – 100 μM with the sensitivity of 0.120 μA/Μm and the detection limit (S/N = 3) of 0.8 μM.

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