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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).

Arjuna Subject : -

Articles 1,981 Documents

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STRUCTURE ELUCIDATION OF ALKALOIDS FROM LEAVES OF Voacanga foetida (Bl.) Rolfe OF LOMBOK ISLAND Surya Hadi; Dina Asnawati; Novi Febrianti
Indonesian Journal of Chemistry Vol 10, No 2 (2010)
Publisher : Universitas Gadjah Mada

The leaves of Voacanga foetida (Bl.) Rolfe, have been used ethnomedically for the treatment of wounds, itches, and swellings particularly in Lombok island. A phytochemical study has been done to investigate chemical compounds responsible against the cause of the diseases. By separating alkaloidal fraction from the leaves was found voacristine 1 as the major alkaloidal compound, and voacangine 2 and coronaridine 3 as the minor components. The structure elucidation of the compounds was carried out on the basis of spectroscopy data. A structure revision of voacristine 1 was also reported.

EFFECT OF PREPARATION METHOD OF Ni CATALYST USING BENTONITE AS THE SUPPORT MATERIAL Hery Haerudin; Silvester Tursiloadi; Galuh Widiyarti; Wuryaningsih Sri Rahayu
Indonesian Journal of Chemistry Vol 3, No 2 (2003)
Publisher : Universitas Gadjah Mada

Nickel catalyst has been prepared impregnation and precipitation with nickel content of 20% and 25% each using bentonite as support material. The effects of the preparation method were studied using temperature programmed oxidation (TPO) and temperature programmed reduction (TPR) and by determination of its specific surface area. The activity of catalysts has been tested in the hydrogenation of palm oil. The catalyst with 20% of nickel and prepared by impregnation shows a single peak at 301°C, compared to catalyst with 25% of nickel prepared by the same method which has a peak at 304°C and a shoulder at 330°C. The reduction curves of both catalysts, those are prepared by impregnation, show a homogeneity indicated by a high main peak at 426°C (20% Ni) and 430°C (25% Ni). The 25% nickel catalyst by impregnation has a shoulder at 508°C. The catalysts prepared by precipitation show peaks at 508°C and 661°C for 20% of Ni and peaks at 419°C and 511°C for 25% of Ni. The reduction curves of catalysts prepared by precipitation are significantly different from each other. Those are also very different comparing to the reduction curve of impregnated catalyst. The 20% precipitated nickel catalyst has a single peak at 540°C, but the 25% precipitated nickel catalyst shows peaks at 346°C and 503°C. The differences of peak position among the reduction curves of catalysts resulted in the differences of catalyst activities with the following order 20% Ni (impregnation) > 25% Ni (impregnation) > 20% Ni (precipitation) > 25% Ni (precipitation).

STUDY ON ADSORPTION OF Cd(II) BY CHITOSAN-ALUMINA Darjito Darjito; Danar Purwonugroho; Siti Nasirotun Nisa
Indonesian Journal of Chemistry Vol 6, No 3 (2006)
Publisher : Universitas Gadjah Mada

One techniques to reduce the concentration of heavy metal Cd(II) in aqueous solution is adsorption by chitosan. To modify the surface textures and expose the active binding sites, composite biosorbent has been prepared by coating chitosan onto alumina. The aims of this research were to identify the functional group of chitosan-alumina, to characterize adsorption of Cd(II) by using chitosan-alumina adsorbent including optimum pH, optimum agitation time, and to determine the adsorption capacity of the adsorbent. The functional group of chitosan-alumina was identified by infrared spectrophotometer. Determination of the optimum condition was carried out at 40 ppm Cd(II), 125 rpm and 0,1 g adsorbent. Calculation of adsorpted Cd(II) based on its concentration in aqueous phase before and after adsorption process. The concentrations of Cd(II) in aqueous phase after adsorption process were determined by using Atomic Absorption Spectroscopy (AAS). Identified functional groups of chitosan-alumina were -OH (3466.39 cm-1), -NH amine (1625.15 cm-1), C=O (1703.30 cm-1), and Al-O (1302.07 cm-1). The optimum pH was reached at pH 7, optimum agitation time at 15 minutes, and adsorption capacity of chitosan-alumina was 15.35 ± 0.05 mg/g.

PHENOL-2-(1-METHYL ETHOXY)-METHYL CARBAMATE COUMPOUND IN ETHYL ACETATE EXTRACT OF STEM BARK OF Aglaia angustifolia Sofnie M. Chairul
Indonesian Journal of Chemistry Vol 8, No 3 (2008)
Publisher : Universitas Gadjah Mada

Isolation of carbamate coumpound from ethyl acetate extract of stem bark of Aglaia angustifolia (Meliaceae), was carried out. The dried stem bark of A. angustifolia was extracted with ethanol (polar solvent), ethyl acetate (medium of polar) and water. From there extract solvent was biological activity test to Crocidolomia binotallis. Ethyl acetate extract solvent more active than another solvent, so that this extract was fractioned and clean up using chromatograpgy column, use SiO2 as stationary phase, mixture of n-hexane/ethyl acetate (10:1 ~ 1:1), ethyl acetate, and ethanol respectively as elution solution. The result of Biological activity test to C. binotallis showed that fraction of ethyl acetate inhibited growth on LC50 3.57 ppm. The compound of isolation result using HPLC, GCMS, FTIR and NMR was identified as phenol-2(1-methyl ethoxy) methyl carbamate coumpound, active as botanical insecticide.

PHENOLIC COMPOUND FROM THE STEM BARK OF MANGGIS HUTAN (Garcinia bancana Miq.) AND THEIR ANTIOXIDANT ACTIVITY Muharni Muharni; Supriyatna Supriyatna; Husein H. Bahti; Dachriyanus Dachriyanus
Indonesian Journal of Chemistry Vol 9, No 2 (2009)
Publisher : Universitas Gadjah Mada

A phenolic compoud, (-)-epicatechin, was isolated from the stem bark of Garcinia bancana. The structure of this compound was determined base on spectroscopic data such as including UV, IR, 1-D, 2-D NMR, and comparison with the reported data. Biological activity of this compound at free radical scavenging activity by 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and inhibitory xanthine oxidase(XO) activity showed that (-)- epicathechin active at two methods with IC50 value 8.1 and 8.6 mg/mL respectively.

UTILIZATION OF RICE HUSK AS RAW MATERIAL IN SYNTHESIS OF MESOPOROUS SILICATES MCM-41 Suyanta Suyanta; Agus Kuncaka
Indonesian Journal of Chemistry Vol 11, No 3 (2011)
Publisher : Universitas Gadjah Mada

The research about synthesis and characterization of MCM-41 from rice husk has been done. Silica (SiO2) was extracted from rice husk by refluxing with 3M hydrochloric solution at 80 °C for 3 h. The acid-leached rice husk was filtered, washed, dried and calcined at 650 °C for 6 h lead the rough powder of rice husk silica with light brown in color. Characterization was carried out by X-ray diffraction (XRD) and FTIR spectroscopy method. Rice husk silica was dissolved into the sodium hydroxide solution leading to the solution of sodium silicate, and used as silica source for the synthesis of MCM-41. MCM-41 was synthesized by hydrothermal process to the mixture prepared from 29 g of distilled water, 8.67 g of cetyltrimethyl ammonium bromide (CTMAB), 9.31 g of sodium silicate solution, and amount mL of 1 M H2SO4. Hydrothermal process was carried out at 100 °C in a teflon-lined stainless steel autoclave heated in the oven for 36 h. The solid phase was filtered, then washed with deionised water, and dried in the oven at 100 °C for 2 h. The surfactant CTMAB was removed by calcination at 550 °C for 10 h with heating rate 2 °C/min. The as-synthesized and calcined crystals were characterized by using FTIR spectroscopy, X-ray diffraction and N2 physisorption methods. In order to investigate the effect of silica source, the same procedure was carried out by using pure sodium silicate as silica source. It was concluded that silica extracted from rice husk can be used as raw materials in the synthesis of MCM-41, there is no significant difference in crystallinity and pore properties when was compared to material produced from commercial sodium silicate.

THE DETERMINATION OF OPTIMUM CONDITION FOR THE SYNTHESIS OF ALKYL MONOETHANOLAMIDE FROM PALM KERNEL OIL Hilyati Hilyati; Wuryaningsih Wuryaningsih; M. Nasir; Tasrif Tasrif; T. Beuna
Indonesian Journal of Chemistry Vol 4, No 2 (2004)
Publisher : Universitas Gadjah Mada

Synthesis of alkyl monoethanolamide from palm kernel oil was done by two steps reaction that are esterification and amidation. The esterification, that is the reaction between palm kernel oil and methanol with mole ratio of 1:3 using acid catalyst (H2SO4) 4 % at temperature 60 OC for two hours, results in methyl ester palm kernel oil. The methyl ester product was produced by amidation reaction on any variation of time, temperature, catalyst, catalyst concentration and ratio of the reactan. The best result of the synthesis (amide conversion of 98.15 %) was obtained at temperature of 160 OC for 6 hours with mole ratio of methyl ester palm kernel oil to ethanol amine (ratio of the reactan) 1:1 using KOH catalyst 0.5 % and H2SO4 catalyst 0.5 %.

BIFLAVONOID COMPOUND FROM THE STEM BARK OF GAMBOGE (Garcinia xanthochymus) Muharni Muharni; Elfita Elfita; Amanda Amanda
Indonesian Journal of Chemistry Vol 11, No 2 (2011)
Publisher : Universitas Gadjah Mada

Garcinia xanthochymus (Guttiferae) commonly known as gamboge, is a perennial medicinal plant native to the north of Thailand and Myanmar. Gamboge is used in watercolors, as a yellow fabric dye and traditional medicine for treating diarrhea and dysentery, dispelling worms clearing away fire and removing food toxin. Phytochemical investigations on the methanol extract of the stem bark of Garcinia xanthochymus resulted in isolation of one biflavonoid compound (+)-morelloflavon. The structure of this compound was deduced on basis of spectroscopic data including 1H NMR, 13C NMR, HMQC and HMBC and comparison with the reported data. This compound has been reported from others species of Garcinia.

PREVENTION OF PROTEIN ADSORPTION ON BARE FUSED-SILICA CAPILLARY BY PEG IN CAPILLARY ZONE ELECTROPHORESIS Adhitasari Suratman; Hermann Waetzig
Indonesian Journal of Chemistry Vol 9, No 3 (2009)
Publisher : Universitas Gadjah Mada

The protein separation was studied in capillary zone electrophoresis for preventing protein adsorption on the capillary wall. ß-lactoglobulin (pI: 4.83-5.4, Mr: 18.4 kDa), cytochrome c (pI: 9.59, Mr: 11.7 kDa) and ß-casein (pI: 4.6, Mr: 24 kDa) were used as protein models. Strong adsorption of the proteins occurred onto the capillary at a pH around their pIs. In order to prevent protein adsorption, PEG (Poly(ethylene glycol)) was investigated as an effective substance to stabilize the proteins native state and coat the bare fused-silica capillary surface. The presence of 32 mg/mL PEG in buffer solution in a pH range of 6.0 to 4.0 was successful to suppress protein adsorption during the separation. It can also be confirmed with the reproducibility of apparent EOF mobility with percentile RSD (Relative Standard Deviation) less than 2% in long-term measurement.

CHARACTERIZATION OF MODIFIED BENTONITE USING ALUMINUM POLYCATION Hery Haerudin; Nino Rinaldi; Adel Fisli
Indonesian Journal of Chemistry Vol 2, No 3 (2002)
Publisher : Universitas Gadjah Mada

The modification of bentonite by pillarization using aluminum polycation type Keggin [Al13O4(OH)24(H2O)12]7+ has been carried out, by exchange of cation from interlayer with aluminum polycation. The amount of aluminum polycation, which was used for the pillaring of bentonite was varied, i.e. 5 mmol/gram, 10 mmol/gram, and 20 mmol/gram of bentonite. After drying, the pillared bentonite was calcined at 400 oC for 6 hour with temperature rate of 5 oC/min. The cationic exchange capacity (CEC) of starting bentonite was 98.3 meq/100 gram. The concentration ratio of Al/Si increased from 0.27 to 0.34 for pillared bentonite and of Ca/Si was decreased from 0.06 to 0.006 for pillared bentonite. The basal space for pillared bentonit increased significantly from 7.30 Å to about 18 Å . The measured specific surface area (by BET) of pillared bentonite was also increased significantly from 46 m2/g to about 162 m2/g. It was concluded that bentonite has been pillared by aluminum polication successfully.

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