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Indonesian Journal of Chemistry

ijc
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Published by Universitas Gadjah Mada

ISSN : 14119420 EISSN : 24601578 DOI : -

Core Subject : Science, Engineering,

Chemical Engineering, Chemistry & Bioengineering Chemistry

Indonesian Journal of Chemistry is an International, peer-reviewed, open access journal that publishes original research articles, review articles, as well as short communication in all areas of chemistry including applied chemistry. The journal is accredited by The Ministry of Research, Technology and Higher Education (RISTEKDIKTI) No : 21/E/KPT/2018 (in First Rank) and indexed in Scopus since 2012. Since 2018 (Volume 18), Indonesian Journal of Chemistry publish four issues (numbers) annually (February, May, August and November).

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Articles 1,981 Documents

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ISOLATION AND CHARACTERIZATION OF CHITIN AND CHITOSAN PREPARED UNDER VARIOUS PROCESSING TIMES Crescentiana Dewi Poeloengasih; Hernawan Hernawan; M. Angwar
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

Generally production of chitosan from crustacean shells consists of 4 steps, i.e. deproteinization, demineralization, decolorization and deacetylation. Simplification of chitosan production by elimination of deproteinization and/or demineralization, or reducing of reaction time would give many advantages, e.g. reduction of processing time and cost production due to reduction of chemical and power usage. The objectives of this research were to prepare chitosan under various processing times and to characterize the obtained chitin and chitosan. Chitin was prepared under various deproteinization times (0, 15, 30 min at 90 ºC using NaOH 2N) and demineralization times (0, 15, 30 min at ambient temperature using HCl 2N). Chitin was then bleached using aceton/etanol (1:1) for an hour. Deacetylation was achieved by treatment of chitin under condition at 120 ºC for 5 hr using NaOH 50%. Ash and nitrogen content, and degree of deacetylation of chitosan were evaluated. Demineralization and/or deproteinization times influenced the quality of chitin. Chitin and chitosan prepared without demineralization had white and chalky appearance, whereas the other chitosan were off-white in color. Ash and nitrogen contents of the chitosan products were 0.18 - 32.40% and 3.56 - 7.59%, respectively. Chitosan prepared under various processing times, except chitosan without demineralization treatment, had degree of deacetylation ≥ 70%.

SYNTHESIS OF p-METHOXY-CYNNAMIL- p-METOXYCINAMATE FROM ETHYL p-METHOXYCINAMAT WAS ISOLATED FROM DRIED RHIZOME Kaempferia Galanga L AS SUNSCREEN COMPOUND Titik Taufikkurohmah
Indonesian Journal of Chemistry Vol 5, No 3 (2005)
Publisher : Universitas Gadjah Mada

Synthesis of p-methoxy-cynnamil-p-methoxy-cinnamate, (PMS)2O from ethyl-p-methoxy-cinnamate (EPMS) from dry rhizome of kaempferia galanga L as sunscreen compound have been done. Isolation of EPMS was done by percholation using ethanol 96 % and recrystallitation using methanol to have 2.2 % yield. Hydrolysis of EPMS using alcoholic KOH resulted methoxycinnamic acid (APMS) of 90.26 % yield. Reduction EPMS using lithium aluminium hydride in dry ether would give p-methoxycinnamoyl alcohol (PMS-OH) of 41.98 % yield. Then reaction of p-methoxycinnamoyl chloride (PMS-Cl) and PMS-OH in chloroform would produce p-methoxycinnamoyl p-methoxycinnamate ((PMS)2O) of 1.77 % yield. All compound were identified by TLC and several spectrometry methodes i.e. U.V Vis, IR, 1H-NMR and GC-MS.

POTENCY OF MUNG BEAN SPROUT AS ENZYME SOURCE (α-AMILASE) Suarni Suarni; Rauf Patong
Indonesian Journal of Chemistry Vol 7, No 3 (2007)
Publisher : Universitas Gadjah Mada

Mung bean sprouts contain enzyme of α-amylase. A research on the effect of the sprout age and sprout varieties to the α-amylase activity and the protein level has been carried out in Laboratorium Bioproses BB Pascapanen Bogor using Full Factorial Random Design with two factorials (1) sprout age; 1, 2, 3, 4, and 5 days as well as (2) varieties of mung bean; Kenari, Bhakti and Parkit. Parameters observed were water and protein content of sprout, pH, activities of α-amylase, and dissolved protein in the enzyme extract. Results showed that the optimum temperature of α-amylase was 30 ºC, the highest protein level of sprout and the highest activity of α-amylase were given by the sprout of Bhakti at the age of three days. The water content in sprout was 65.23%, the protein level was 12.93 %, the dissolved protein in the enzyme extract was 2.88743 mg/mL, pH was 5.45, and the activity of enzyme was 4.09 Unit/mL. The potency of enzyme found in mung bean can be utilized in industries processing materials having high starch content, such as maize flour.

Synthesis of Cassava Waste Pulp-Acrylamide Super Absorbent: Effect of Initiator and Cross-Linker Concentration Zainal Alim Mas’ud; Mohammad Khotib; Nurmutia Sari; Anwar Nur
Indonesian Journal of Chemistry Vol 13, No 1 (2013)
Publisher : Universitas Gadjah Mada

Cassava waste pulp (CWP) contains high carbohydrates that can be modified into super absorbent polymer (SAP) through grafting and cross-linking copolymerization. Acrylamide (AM) was grafted onto CWP with ammonium persulfate (APS) as the initiator and N,N'-methylene-bis-acrylamide (MBA) as the cross-linker under atmospheric nitrogen. The effect of APS and MBA concentrations on water absorption capacity of saponified SAP was studied, while the evaluation of grafting ratio (GR) and grafting efficiency (GRE) was conducted on unsaponified SAP. The grafting success was indicated by the occurrence of IR peaks at wave numbers of 573, 765, 858, and 1667 cm-1. In the saponified SAP, the very intense characteristic band at 1562 cm-1 is due to C=O asymmetric stretching in the carboxylate anion. Saponification increases significantly water absorption capacity compared to that of unsaponified SAP (from 39.79 g/g to 578.23 g/g). The highest water absorption capacity is reached at 0.74% APS and 0.09% MBA. The percentage of GRE and GR tends to increase with increasing APS concentration until reaching the highest value and then decreases. Effect of MBA concentration on water absorption capacity, GR, and on GRE is similar to the effect of initiator concentration on GR and GRE.

MOLECULAR DOCKING OF D6-ANHYDROERYTHROMYCIN TO rRNA 23S Deinococcus radiodurans AND THE PREDICTION OF ITS ANTIBIOTIC POTENCY Winarto Haryadi; Umar Anggara Jenie; Retno Sunarminingsih Sudibyo; Harno Dwi Pranowo; Fajar Rakhman Wibowo
Indonesian Journal of Chemistry Vol 9, No 2 (2009)
Publisher : Universitas Gadjah Mada

D6-anhidroeritromisin-A is a new derivative of erythromycin which is synthesized through biosynthetic engineering technique. The molecular docking in rRNA 23S Deinoccocus radiodurans are accomplished to determine the model and strength of binding to the target macromolecule. The molecular docking of erythromycin-A and 6-deoksieritromisin-A to the same macromolecule is used as a control. The docking result of the D6-anhidroeritromisin-A shows that it occupies the same cavity as of the experimental erythromycin-A in the same macromolecule. The binding position of D6-anhidroeritromisin-A is not exactly same as erythromycin-A and 6-deoksieritromisin-A due to the presence of D6 unsaturated double bond. However the hydroxyl group(OH) at C-6 does not have an apparent effect on the binding model to rRNA23S D. radiodurans.

SYNTHESIS OF 3,4-DIMETHOXY ISOAMYL CINNAMIC AS THE SUNSCREEN COMPOUND FROM CLOVE OIL AND FUSEL OIL Tutik Dwi Wahyuningsih; Tri Joko Raharjo; Iqmal Tahir
Indonesian Journal of Chemistry Vol 2, No 1 (2002)
Publisher : Universitas Gadjah Mada

Synthesis of sunscreen compound 3,4-dimethoxy isoamyl cinnamic from clove oil and fusel oil has been done. The majoring component of clove oil that is eugenol has been isolated, followed with several chemical processes i.e. isomerization into isoeugenol, oxidation of the product to change into vanillin, then modification vanillin into veratraldehyde. From the fusel oil, we isolate isoamyl alcohol and modified by acetylation into isoamyl acetic. The final product could be produce by Claissen's condensation of isoamyl acetic and veratraldehyde to give 3,4-dimethoxy isoamyl cinnamic. All of the processes are followed with structure characterization using GC, IR, GC-MS and 1H-NMR spectroscopy. The result shown that compound has 46.98% purity and potent as the UV-B sunscreen's type (lmax = 313 nm). In-vitro sunscreen's activity of the compound was tested by UV-Vis spectrophotometry and resulting a maximum Sun Protection Factor value (SPFin-vitro) at low concentration, 10.25 mg/mL.

INTERPRETATION OF OXYGEN –18 ISOTOPE IN SULPHATE FROM DEEP GROUNDWATER IN JAKARTA AREA E. Ristin Pujiindiyati; Wandowo Wandowo; Zainal Abidin
Indonesian Journal of Chemistry Vol 7, No 1 (2007)
Publisher : Universitas Gadjah Mada

It has been done a determination of d 18O (SO42-) and d 18O (H2O) value from Jakarta deep groundwater with depth 40-140 m. The aim of this research is to know some procesess influencing the composition of oxygen isotope in groundwater sulphate. A method commonly used to determine d 18O (H2O) value is according to Epstein-Mayeda. CO2 gas resulted from equilibration process between water sample and CO2 gas standard in which oxygen isotopic reaction has occurred, is injected to mass spectrometer. For determination of d 18O (SO42-) value, Rafter method is used. CO2 gas released from reducing sulphate of water sample with graphite is injected to mass spectrometer. The results of d 18O (H2O) values obtained in this experiment have a narrow range from -5,04 0/00 to -6,65 0/00 SMOW whereas their d18O (SO42-) values have a wider range from +8,3 0/00 to +17,4 0/00 SMOW. The more constant values of d 18O (H2O) performed that evaporation effects might not occur. Based on the similarity between d18O (SO42-) values of deep groundwater and that of marine evaporite sulphate rocks, it is supposed that sulphate of Jakarta deep groundwater was derived from dissolution of this rocks. There was an indication of seawater intrusion around Pejagalan and Kamal Muara Penjaringan area based on the similarity between their d18O (SO42-) values and d18O (SO42-) of modern seawater. The contribution of oxygen from water in sulphide oxidation reaction ranged 0% to 12% suggesting that oxygen in deep groundwater sulphate was mainly derived from atmospheric molecular oxygen.

STUDY OF THE FORMATION OF MESOPOROUS TiO2 USING ISOPROPOXIDE PRECURSORS UNDER LESS WATER CONDITIONS Indriana Kartini; Gao Qing Lu
Indonesian Journal of Chemistry Vol 5, No 1 (2005)
Publisher : Universitas Gadjah Mada

The role of the synthesis parameters (the molar ratio of template, isopropyl alcohol, acetylacetone, and water with respect to titanium(IV) tetraisopropoxide) has been thoroughly investigated to understand their effects on the mesostructures and the formation of crystalline phases of mesoporous titania xerogels in less water condition (no added water) at 60 oC. The resultant mesoporous titania are more likely to have worm-hole like structure as the dominant stable structure. The template appears to play no significant role in structure directing at mesophase level. However, increasing the amount of the template delays the formation of anatase crystalline phase.

WAX ESTERS PRODUCTION BY ALCOHOLYSIS OF PALM OIL FRACTIONS Erin Ryantin Gunawan; Dedy Suhendra
Indonesian Journal of Chemistry Vol 8, No 3 (2008)
Publisher : Universitas Gadjah Mada

The lipase synthesis of wax esters using palm oil fractions (palm oil and palm kernel oil) and long chain alcohol as substrates was carried out. The present work focuses on the synthesis of wax esters using Lipozyme. Five parameters such as reaction time, temperature, amount of enzyme, molar ratio of substrates and various organic solvents of the reaction system were investigated. The optimum yields were achieved at the reaction temperature of 40 - 50 °C for palm oil (PO) and 40 °C for palm kernel oil (PKO) alcoholysis, a reaction time of 5 - 7 h for PO and 7 - 10 h for PKO alcoholysis, 0.15 g of enzyme for both PO and PKO alcoholysis, molar ratio at 3:1 (alcohol: PO or PKO), and the best solvent for the reactions was hexane. Percentage yields of esters obtained at these optimum reaction conditions was 83% refined, bleached and deodorized (RBD) palm oil alkoholysis and 87% for RBD palm kernel oil alcoholysis respectively

RAPID SOLVENT-FREE MICROWAVE ASSISTED SYNTHESIS OF SOME N’-BENZYLIDENE SALICYLIC ACID HYDRAZIDES Tutuk Budiati; Stephanie D.A.; Elisabeth Catherina Widjajakusuma
Indonesian Journal of Chemistry Vol 12, No 2 (2012)
Publisher : Universitas Gadjah Mada

Condensation reaction has been carried out for the synthesis of some N'-benzylidene-2-hydroxybenzohydrazides using microwave assisted solvent-free method. The structures of all the products obtained in the present work are supported by spectral and analytical data (UV, IR, and 1H-NMR spectroscopy). The desired hydrazides are in 62-80% yields under microwave irradiation. The reaction was completed in 8-10 min.

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