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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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PREPARATION OF CHITOSAN-GOLD NANOPARTICLES: PART 1 (OF 2). EFFECT OF REDUCING TECHNIQUE Adlim Adlim; Mohamad Abu Bakar
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

Chitosan-stabilized gold nanoparticles were synthesized in aqueous formic acid, citric, or acetic acid with and without chitosan as the stabilizer. Refluxing in methanol, addition of hydrazine or sodium borohydride, photo-irradiation were employed as the reducing agents & reduction technique of gold ions. Dispersed particles of chitosan-stabilized gold were obtained in aqueous acetic acid-methanol solution. The chitosan-stabilized gold colloids (chi-Au) were dispersed and the particle size were in range of 9-30 nm, some of which were crystalline with various shapes. Chi-Au prepared with hydrazine as the reducing agent resulted in large and aggregated particles. The finest and dispersed chi-Au particles were obtained if NaBH4 was used as the reducing agent and the diameters could be controlled within 2.2-2.3 nm.

COORDINATION STATE AND AGGREGATION PROCESS OF BACTERIOCHLOROPHYLL A AND ITS DERIVATIVES : STUDY ON ACETONE-WATER AND METHANOL-WATER SOLVENTS Heriyanto Heriyanto; Suryasatriya Trihandaru; Leenawaty Limantara
Indonesian Journal of Chemistry Vol 9, No 1 (2009)
Publisher : Universitas Gadjah Mada

Research on bacteriochlorophyll (BChl) a and its derivatives had been conducted to determine the coordination state and the aggregation process in acetone-water and methanol-water. The results showed that there were mainly two absorption peaks in BChl a and its derivatives, namely: Qx and Qy that were very sensitive to coordination state and aggregation process. The coordination state of pigment could be determined based on Qx absorption peak that was influenced by solvents. In addition, the donor number (DN) and taft parameters (β and π*) from each sovents could also be used to determine the coordination state. One or two of axial coordination toward center metal of BChl a and its derivatives have to be filled by donor electron as a foreign nucleophile. Mg-BChl was exist as five-coordinate complexes in acetone but as six-coordinate complexes in methanol. Five-coordinate complexes of Zn-BChl was occurred either in acetone or methanol. Cu-BChl was exist as four-coordinate complexes in acetone but altered to five-coordinate complexes in methanol. The agregation process was influenced by the existence of water added in pigment solution. The order of Mg-BChl a and its derivatives abilities to form new aggregate in acetone-water and methanol-water, in regard of water-addition percentage was as follow: Cu-BChl > Zn-BChl > Mg-BChl. Methanol was the solvent that could form aggregate of Mg-BChl and its derivatives at lower water-addition percentage compared to acetone.

IN VITRO IRON AVAILABILITY AND ADSORPTION PATTERN ON COMBINATION OF ACIDITY AND LENGTH OF BOILING TIME ON YARD LONG BEAN Leny Yuanita
Indonesian Journal of Chemistry Vol 5, No 3 (2005)
Publisher : Universitas Gadjah Mada

The aim of the study is to find iron availability and binding pattern by dietary fiber macromolecule on combination of acidity and length of boiling time, through Kads and Keff, boiling procees at the level of pH 4 and 7 with boiling time at 0 (raw), 5, 15, and 25 minutes. Iron availability and adsorption pattern were analyzed through Miller's in-vitro and Langmuir-Scatchard graph methods. The results of the study showed: (1) the highest iron availability occurs at raw-pH4 treatment; (2) decreasing pH and increasing boiling time decrease Kads,Keff, percent iron bound, and increase iron availability; (3) iron binding pattern by dietary fiber macromolecules through formation of complex compound was more prominent than physical adsorption, involving two types of specific binding sites, one of which showed a higher affinity.

TITANIUM OXIDE DISPERSED ON NATURAL ZEOLITE (TiO2/ZEOLITE) AND ITS APPLICATION FOR CONGO RED PHOTODEGRADATION Is Fatimah; Eko Sugiharto; Karna Wijaya; Iqmal Tahir; Kamalia Kamalia
Indonesian Journal of Chemistry Vol 6, No 1 (2006)
Publisher : Universitas Gadjah Mada

The utilization of TiO2 dispersed on natural zeolite (TiO2/Zeolite) for degradation of Congo Red photocatlytically has been performed. The TiO2/Zeolite was prepared by mechanically mixing of 100 g of natural zeolite, which it has been heated at 400oC, with TiO2 powder, the final weight ratio of the mixture was 5% (w/w). The mixture was then calcined at 400oC for 6 hours. The calcined product was characterized using x-ray diffractometry, x-ray fluorescence analysis and gas sorption analysis methods to determine its physicochemical properties changes caused by mixing and calcination. Investigation of Congo Red photodegradation using TiO2/Zeolite was carried out by mixing 25 mL 10-4 M solution of Congo Red with 25 mg of TiO2/Zeolite and irradiating the suspention with UV-light of 350 nm for 10, 20, 30, 40, 50 and 60 minutes, respectively. The characterization results showed that dispertion of TiO2 on zeolite resulted in the increasing of titanium concentration on TiO2/Zeolite. The concentration of Ti on natural zeolite was found to be 0.15%(w/w), meanwhile on TiO2/Zeolite was 2.29% (w/w). From X-ray diffractometry analysis result no information was found that TiO2 was dipersed on natural zeolite. It was caused by overlapping of the reflections of zeolite with reflections of TiO2. On the otherhand, the gas sorption analysis result exhibited that the dispersion of TiO2 on zeolite resulted in the decreasing of total pore volume as well as specific surface area of the natural zeolite. The specific surface areas of natural zeolite and TiO2/Zeolite were 21.98 and 16.74 m2/g, respectively, meanwhile the total pore volumes of natural zeolite and TiO2/Zeolite were 20.10x10-3 and 13.47x10-3 mL/g. The simple kinetic of photodegradation of Congo Red exhibited that the rate of degradation followed a first order kinetic and the reaction rate constant was 0.0017 minute-1.

SYNTHESIS OF POLYETHYLENE OXIDE (PEO)–CHITOSAN HYDROGEL PREPARED BY GAMMA RADIATION TECHNIQUE Erizal Erizal; Thamrin Wikanta
Indonesian Journal of Chemistry Vol 11, No 1 (2011)
Publisher : Universitas Gadjah Mada

Crosslinked PEO hydrogel containing chitosan for wound dressing has been prepared by gamma radiation technique. Chitosan solutions with different concentration (0.5-2% w/v) have been blended with 5% aqueous solution of PEO and irradiated at the doses 20-40 kGy by gamma rays. The copolymers were characterized by Fourier transform infra red spectroscopy and their physico-chemical properties of hydrogels were evaluated in terms of gel fraction, swelling ratio, elongation at break and antimicrobial activities. It was found that under maximum condition of incorporation 1% chitosan with irradiation dose of 20 kGy, PEO-chitosan hydrogels with high gel fraction (85%), swelling ratio (10 g/g) and elongation at break (145%) were obtained. The examination of the microbe penetration shows that the prepared hydrogels can be considered as a good barrier against microbes. Thus, PEO-chitosan hydrogel showed satisfactory properties for use as a wound dressing.

THE PORIFERASTA COMPOUND-5,22E,25-TRIEN-3-Oβ FROM Clerodendrum paniculatum LEAF AS INDUCER AGENT OF SYSTEMIC RESISTANCE ON RED CHILLI PLANT Capsicum annuum L FROM CUCUMBER MOSAIC VIRUS (CMV) Weny Musa; Hersanti Hersanti; Achmad Zainuddin; Roekmi-ati Tjokronegoro
Indonesian Journal of Chemistry Vol 9, No 3 (2009)
Publisher : Universitas Gadjah Mada

The poriferasta-5.22E.25-trien-3β-ol compound of leaves of this plant Clerodendrum paniculatum has activity as an inducer agent of plant systemic resistance of red plant toward Cucumber Mosaic Viruses (CMV), the inhibition activity compound shows 82% inhibition activity at 300 ppm. The structure of these compound were determined on the basis of spectroscopic data including UV, IR, 1H-NMR, 13C-NMR and 2D-NMR

DETERMINATION OF MANY-BODY EFFECT OF [Co(NH3)n]2+ (n=1-6) COMPLEXES BASE ON AB INITIO CALCULATIONS Harno Dwi Pranowo; Karna Wijaya; Bambang Setiaji; Rhano Setyan Janu
Indonesian Journal of Chemistry Vol 2, No 1 (2002)
Publisher : Universitas Gadjah Mada

The computational chemistry calculation to determine the stabilization energy and ligand-ligand repulsion energies of [Co(NH3)n]2+ system was done by using LANL2DZ basis set for Co2+ and 6-31G* basis set for NH3 at the level theory of unrestricted Hartree-Fock (UHF). Result from the calculation shows that the larger number of NH3 ligand present in the complex give the effect of the lower average binding energy per ligand molecule, i.e. -503,29 kJ/mol for [Co(NH3)]2+ and then decrease to -338,025 kJ/mol for octahedral [Co(NH3)6]2+ complex. A correlation between the number of ligand and the metal ion-ligand bond distance was studied. The result shows that the metal ion-ligand bond distance increases along with the larger number of the ligand. The calculation of average pair interaction energies between Co2+ and NH3 in [Co(NH3)n]2+ complexes were done in order to determine the error possibility caused by the neglect of non-additivity contribution. The results indicate that the maximum relative error with respect to the pair potential, %ΔEavpi, is 17,64 % [Co(NH3)6]2+ complex.

ANTIMICROBIAL ACTIVITIES OF Shorea foxworthyi Sym STEAM BARK METHANOL EXTRACT Andi Hairil Alimuddin; Masriani Masriani
Indonesian Journal of Chemistry Vol 8, No 1 (2008)
Publisher : Universitas Gadjah Mada

Screening of antimicrobial activity compound from steam bark of Shorea foxworthyi Sym by Thin Layer Chromatography-Bioautography method have been conducted. The result of this research can be base in elucidation of antimicrobial activity compounds from S. foxworthyi Sym. The first step was done in this research that is maceration of S. foxworthyi steam bark using methanol solvent. Fractination to methanol extract was done using n-hexane, chloroform, and ethyl acetate solvent, respectively. Phytochemical screening were done to methanol, chloroform, n-hexane, and ethyl acetate fractions. Screening of antimicrobial activity compound were done to polar fraction such as methanol, chloroform, and ethyl acetate fraction. The bacteria were used in this screening such as E. coli, S. aureus, S. thypii, and B. Subtilis. The extract was highest antimicrobial activity choosed to test by Thin Layer Chromatography-Bioautography. The result was showed that chloroform extract was had highest antimicrobial activity and the flavonoide of compaund was considered having antimicrobial activity.

QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIP ANALYSIS (QSAR) OF VINCADIFFORMINE ANALOGUES AS THE ANTIPLASMODIAL COMPOUNDS OF THE CHLOROQUINOSENSIBLE STRAIN Iqmal Tahir; Mudasir Mudasir; Irza Yulistia; Mustofa Mustofa
Indonesian Journal of Chemistry Vol 5, No 3 (2005)
Publisher : Universitas Gadjah Mada

Quantitative Structure-Activity Relationship (QSAR) analysis of vincadifformine analogs as an antimalarial drug has been conducted using atomic net charges (q), moment dipole (μ), LUMO (Lowest Unoccupied Molecular Orbital) and HOMO (Highest Occupied Molecular Orbital) energies, molecular mass (m) as well as surface area (A) as the predictors to their activity. Data of predictors are obtained from computational chemistry method using semi-empirical molecular orbital AM1 calculation. Antimalarial activities were taken as the activity of the drugs against chloroquine-sensitive Plasmodium falciparum (Nigerian Cell) strain and were presented as the value of ln(1/IC50) where IC50 is an effective concentration inhibiting 50% of the parasite growth. The best QSAR model has been determined by multiple linier regression analysis giving QSAR equation:Log (1/IC50) = 9.602.qC1 -17.012.qC2 +6.084.qC3 -19.758.qC5 -6.517.qC6 +2.746.qC7 -6.795.qN +6.59.qC8 -0.190.μ -0.974.ELUMO +0.515.EHOMO -0.274.α +0.029.A -1.673 (n = 16; r = 0.995; SD = 0.099; F = 2.682)

THE EFFECTS OF GRADIENT VELOCITY AND DETENTION TIME TO COAGULATION – FLOCCULATION OF DYES AND ORGANIC COMPOUND IN DEEP WELL WATER Muhamad Lindu
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

The treatment of deep well water of Trisakti University by coagulation and flocculation using baffle channel system has been conducted. The detention time of hydrolic were varied. The coagulant dose was varied as 50, 100, 150, 200, 300, 350, 400, 450 and 500 ppm. Water of well sampel was added by coagulant with rotation velocity 200 rpm for 1 minute. The optimal coagulant dose was determined by measuring turbidity, colour, total suspended solids and organic compound. The result showed that the organic compound and colour of deep well water of Trisakti University could be reduced by coagulation and flocculation process by hydrolyc system. The optimal dose of the coagulant was 250 ppm. The removal efficiency of colour and organic compound using optimal dose for continuous flow reactor reached after water flow passed the reactor for 3 - 5 times detention time in the reactor. The optimal gradient velocity (G) was 30 - 35 sec-1 and collision energy (GT) was 65.000 - 79.000 to get optimal flocculation. With this condition, the removal efficiency of turbidity, colour and organic was more than 90%.

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