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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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CYCLIZATION AND HYDROGENATION OF (+)-CITRONELLAL TO MENTHOLS OVER ZnBr2 AND Ni CATALYSTS SUPPORTED ON γ-Al2O3 Elvina Dhiaul Iftitah; M. Muchalal; Wega Trisunaryanti; Ria Armunanto
Indonesian Journal of Chemistry Vol 10, No 2 (2010)
Publisher : Universitas Gadjah Mada

Two steps transformation of (+)-citronellal, cyclization and hydrogenation, on ZnBr2/γ-Al2O3 and Ni/γ-Al2O3 catalyst have been realized with the selectivity to cyclization products (isopulegols) was very high (yield up to ~92.58%) over ZnBr2/γ-Al2O3 under mild condition (90 °C and 1 atm nitrogen atmosphere) with high Brønsted acid concentration, while at the same time very low cyclization rates were achieved over Ni/γ-Al2O3 with low or no Brønsted acidity, respectively. The highest cyclization rates were observed over Ni/ZnBr2/γ-Al2O3 under mild condition (90 °C and 1 atm hydrogen atmosphere). The second step transformation towards cyclization products, hydrogenation to menthols, was performed with Ni/γ-Al2O3 under hydrogen atmosphere. Surprisingly the one-step transformation of (+)-citronellal into menthols was investigated over Ni/γ-Al2O3 with yield ~84% under hydrogen atmosphere (90 °C, 1 atm) by exploiting the presence of acidic and hydrogenation sites on the catalyst surface. On the Ni/γ-Al2O3 catalyst it was found that the cyclization of (+)-citronellal to isopulegols occurs on the surface of the support. In the presence of the noble metal, the isopulegols are further hydrogenated to the menthols.

THE STEREOCHEMISTRY EFFECT OF EUGENOL, CIS-ISOEUGENOL AND TRANS-ISOEUGENOL ON THEIR CATALYTIC HIDROGENATION M. Muchalal
Indonesian Journal of Chemistry Vol 4, No 2 (2004)
Publisher : Universitas Gadjah Mada

The stereochemistry effect of eugenol, cis-isoeugenol and trans-isoeugenol on their catalytic hydrogenation by Ni/g-Al2O3 catalyst was investigated. In this investigation, the catalyst is prepared by impregnation of Nickel into solid of γ-Al2O3 in methanol as a solvent. The calcination process, which is followed by reduction, is performed on Muchalal reactor at 400 oC. After that, the catalytic hydrogenation is carried out under hydrogen gas atmosphere by mixing 10 mL sample and 0.5 g Ni/g-Al2O3 catalyst at 200 oC for 3 hours. The stereochemistry effect of reactants is evaluated by computer modelling using PM3 semiempirical methods. The mass spectrum of catalytic hydrogenation product from those compounds shows a molecular ion at m/z 164, which proves the existence of 2 -methoxy-4-propylphenol. The eugenol gives the highest conversion (99%), followed by cis-isoeugenol (81%) and trans-isoeugenol (67%). It was found that there is a correlation between the stereochemistry of those compounds and catalytic reactivity.

ANTIOXIDANT ACTIVITY OF 2,6,4’-TRIHYDROXY-4-METHOXY BENZOPHENONE FROM ETHYL ACETATE EXTRACT OF LEAVES OF MAHKOTA DEWA (Phaleria macrocarpa (Scheff.) Boerl.) Susilawati Susilawati; Sabirin Matsjeh; Harno Dwi Pranowo; Chairil Anwar
Indonesian Journal of Chemistry Vol 11, No 2 (2011)
Publisher : Universitas Gadjah Mada

Mahkota dewa plant (Phaleria macrocarpa (Scheff.) Boerl.) which is included into family of Thymelaeaceae is one of Indonesia's traditional medicines. Chemical constituent has been isolated from ethyl acetate extract of leaves of mahkota dewa. Sample was extracted with methanol, concentrated then extracted by n-hexane, chloroform and ethyl acetate. The ethyl acetate extract was separated and fractionated by column chromatography. The first fraction was purified by TLC preparative and recrystalization. Compound was isolated as red-brown spherical crystal in 8 mg (m.p. 129-131 °C). Its spot gave dark fluoroscence at TLC plate (UV366) with Rf of 0.3 at TLC chromatogram with eluent of n-hexane : ethyl acetate (7:3); 0.6 with n-hexane : ethyl acetate (1:1); 0.9 with -hexane : ethyl acetate (4:6). This compound was dissolved in methanol. Compound was identified by UV, IR, 1H NMR, 13C NMR and NMR 2 dimension (HMQC, COSY, HMBC and DEPT-135) spectroscopic as 2,6,4'-trihydroxy-4-methoxybenzophenon. This compound as well as the ethyl acetate extract showed antioxidant activity on DPPH with IC50 was 10.57 and 101.06 μg/mL, respectively. This compound showed strong antioxidant activity on DPPH, almost to the standard antioxidant activity of quercetin (IC50 of 2.93 μg/mL)

NON PHENOLIC COMPOUNDS ISOLATED FROM THE LEAVES OF FERN Chingia sakayensis (Zeiller) Holtt Suyatno Suyatno; Noor Cholies Zaini; Gunawan Indrayanto; Motoo Tori
Indonesian Journal of Chemistry Vol 6, No 1 (2006)
Publisher : Universitas Gadjah Mada

Two non phenolic compounds namely a wax ester hexacosyl hexadecanoic and a steroid -sitosterol were isolated from the n-hexane extract of the fern Chingia sakayensis (Zeiller) Holtt's leaves. Their structures were elucidated on the basis of the spectrometric evidences (UV, IR, 1H-NMR, 13C-NMR, EIMS and HR-CIMS).

METHYL MERCURY PRODUCTION IN NATURAL-COLLECTED SEDIMENT WITH DIFFERENT GEOCHEMICAL PARAMETERS Markus T. Lasut; Hardin F. Rares; Yoshiaki Yasuda
Indonesian Journal of Chemistry Vol 9, No 3 (2009)
Publisher : Universitas Gadjah Mada

Production of methyl mercury (MeHg) has been shown in laboratory experiments using mercuric chloride (HgCl2) compound released into natural-collected sediments with different geochemical conditions. While the HgCl2 concentration was 30 µl of 113 ppm of HgCl2, the geochemical conditions [pH, salinity, total organic content (TOC), sulfur] of sampled sediments were A: 8.20, 0.00 ppt, 1.97%, and 0.92 ppt, respectively; B: 7.90, 2.00 ppt, 4.69%, and 1.98 ppt, respectively; and C: 8.20, 24.00 ppt, 1.32 %, and 90.90 ppt, respectively. A control was set with no HgCl2. Samples and control were incubated in room temperature of 27 ± 1 °C. Observations were done along 9 days with interval of 3 days. While total Hg was measured using mercury analyzer with Cold Vapor-Atomic Absorbtion Spectrophometer (CV-AAS) system, MeHg was measured by using a gas chromatograph with ECD detector after extracted by dithizone-sodium sulfide extraction method. The result shows that MeHg was found in both treatment and control experiments. The concentrations of the MeHg varied according to the geochemical condition of the sampled sediments. Peak production of MeHg occurred on the third day; however, the production was not significantly affected by the incubation time. Optimum production was found inversely related to the pH, in which highest and lowest the pH formed an ineffectively methylated mercury species. The TOC was significantly correlated to the optimum production. Salinity and sulfate contents were found not correlated to the optimum of MeHg production.

CHITINASE AND CHITINOLYTIC MICROORGANISM : ISOLATION, CHARACTERIZATION AND POTENTIAL Nuniek Herdyastuti; Tri Joko Raharjo; Mudasir Mudasir; Sabirin Matsjeh
Indonesian Journal of Chemistry Vol 9, No 1 (2009)
Publisher : Universitas Gadjah Mada

Chitinase is enzyme that hydrolyzes chitin, a polimer of b-1,4-N-Acetilglucosamine which is the most abundant natural resource after cellulose. Chitinolytic microorganism can be found in environment like soil and water that contain chitin, or in extreme environment which is known as thermofilic microorganism. Chitinolytic microorganism is identified by recognizing the morphological and physiological properties based on Bergey's Manual of Systematic Bacteriology. The sequence data of the 16S rRNA genes is determinated in the GeneBank nucleotide sequence database. Chitinase activity can be qualitatively determined from the clearance zone around the colony formed in agar medium containing colloidal chitin. Chitinase can be utilized as biocontrol agent and derivate chitin as the result of chitinase degradation which can be used in the fieltd of health, food, industry and waste management

NUCLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN Bambang Purwono; Estiana R. P. Daruningsih
Indonesian Journal of Chemistry Vol 5, No 3 (2005)
Publisher : Universitas Gadjah Mada

The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded 93.28 %. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyano)methylbenzaldehyde in 54.39% yield. Reaction with methoxyde ion yielded 4-hydroxy- 3-methoxy-5-(methoxy) -methylbenzaldehyde in 67.80% yield. The nucleophilic substitution reaction showed that trimethylamino substituent of quaternary Mannich base can act as a good leaving group on nucleophilic substitution reactions.

A XANTHONE FROM THE STEM BARK OF MANGGIS HUTAN (Garcinia bancana) Muharni Muharni; Dachriyanus Dachriyanus; Husein H. Bahti; Supriyatna Supriyatna
Indonesian Journal of Chemistry Vol 7, No 3 (2007)
Publisher : Universitas Gadjah Mada

A xanthone, 1,5-dihidroxy-3,6-dimethoxy-2,7-bis-(3-methylbutenyl)xanthone had been isolated from the stem bark of Garcinia bancana Miq. The structure of this compound was elucidated by analysis of spectroscopic data, especially using 1D and 2D NMR spectroscopic data.

Effect of Non Ionic Surfactant Addition to Cellulase Performance in High-Substrate-Loading-Hydrolysis of Palm Oil EFB and Water-Hyacinth Teuku Beuna Bardant; Sudiyarmanto Sudiyarmanto; Haznan Abimanyu; Aisha Kania Hanum
Indonesian Journal of Chemistry Vol 13, No 1 (2013)
Publisher : Universitas Gadjah Mada

Enzymatic hydrolysis with high substrate loading of palm oil (Elaeis guineensis) empty fruit bunch (EFB) and water-hyacinth (Eichhornia crassipes) were investigated as a prior part of ethanol production from lignocelluloses. Commercial surfactant Span 85 and Tween 20 were used as cellulase performance enhancer in hydrolysis process with substrate loading above 20% (w/w). Cellulase performances were compared based on hydrolysis conversion. Hydrolysis conversions of EFB using cellulase with concentration 10 and 15 FPU/g-substrate was 38.55% and 88.80% respectively. Addition 2% (v/v) of Tween 20 to EFB hydrolysis reaction with cellulase concentration 10 FPU/g-substrate gave the conversion 87.30%. This addition enhance the cellulase performance up to 226.5% or similar with the performance of cellulase 15 FPU/g substrate. Addition 2% (v/v) of Span 85 to the similar reaction only enhances cellulase performance to 174.7%. Hydrolysis conversion of boiling-pretreated water-hyacinth and autoclave-pretreated water-hyacinth using cellulase 15 FPU/g-substrate was 45.84% and 52.29% respectively. Addition 2% (v/v) of Tween 20 and Span 85 to boiling-pretreated water-hyacinth hydrolysis with cellulase concentration 15 FPU/g-substrate enhance cellulase performance of 128.9% and 153.5% respectively. Addition 1% (v/v) of Tween 20 and Span 85 to the similar reaction with cellulase concentration 10 FPU/g-substrate gave conversions 51.00% and 53.79% respectively, or similar with conversion of autoclave-pretreated water-hyacinth hydrolysis with 15 FPU/g-substrate.

SPECTROSCOPICAL STUDY OF AN ETHER FRACTION ISOLATE FROM STEAM BARK OF “ JATI” (Tectona grandis, L) Fredryk Mandey; Raimundus Chalik; Ismail Ibrahim
Indonesian Journal of Chemistry Vol 9, No 2 (2009)
Publisher : Universitas Gadjah Mada

This research is aimed to primarily study the spectroscopy of ether fraction of from Jati wood (T. grandis, L). The stem bark of T.grandis, L was firstly extracted undergoes a reflux in methanol solvent. Further, the dried methanol crude extract was extracted with diethyl ether and moreover separated its chemical constituents by using of column chromatography using degraded mixtures of n-hexane - ethyl acetate from 9:1 to 7:3. After a final column chromatography from the E fraction, a white needles crystal with a melting point of 295 - 297.5 °C was resulted. This results was then confirmed undergoes a spectroscopic analysis including UV, FTIR, H-NMR, and Mass spectroscopy to get an acid of 3β-hydroxy-20(29)-lupen-28-oic or commonly known as betulinic acid.

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