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All Journal Journal of Applied Chemical Science ROTOR: JURNAL ILMIAH TEKNIK MESIN Jurnal Saintek Lahan Kering
Theo Da Cunha
Department of Chemistry Faculty of Science and Engineering, Nusa Cendana University
Agriculture, Biological Sciences & Forestry Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Energy Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering Public Health

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The Antioxidant Activities of the Methanol Extracts of Dischidia nummularia Yakoba Tari; Theo Da Cunha; Theodore Y. Lulan; Yohanes Buang
Journal of Applied Chemical Science Volume 1, No. 1 , 2012
Publisher : Journal of Applied Chemical Science

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Abstract

There has been elucidated the antioxidant activities of chloroform and aqueous fract ions of methanol extracts isolated from dischidia nummularia. The study was firstly started by maceration of dischidia nummularia powder in certain quantity of pure methanol solvent and followed by gradual partition of the methanol extract with chloroform and distillated water and then purified with column chromatography. The chemical contents migrated into both those later solvents were detected by GC-MS and their functional groups were detected by FT-IR instruments. Thereafter, the antioxidant activities of the migrated compounds in each those solvents were determined using hydrogen peroxide protocol and the absorbance was read at 240 nm. The ascorbic acid solution was used as control. The results showed that GCMS spectrum indicated the phenol compounds only that are existed within the chloroform and the aqueous fractions of the extract. Furthermore, the FT-IR spectrum showed methylene and ethene groups are existed within those phenol compounds as well as the hydroxyl, carbonyl, aromatic, and keton groups. The average absorbances of compounds contained within the chloroform and aqueous fractions were 0.275 and 0.189, respectively, whereas that of the control was 0.085. Those absorbance data conclusively indicated that higher absorbance higher residue of chromophore content existed within the fraction and higher failures of hydroxylation reactions. Overall, the antioxidant behaviors of the aqueous and chloroform fractions of the dischidia nummularia methanol extracts are contributed by the phenol compounds and the activities of their aqueous fractions are higher than those of the chloroform fractions.
Identification and Characterization of Terpenoid Compounds Isolated from Tadalinu Stem bark of Grewia Eriocarpa Juss Extracts Alethia E. Siahainenia; Febri O. Nitbani; Theo da Cunha
Journal of Applied Chemical Science Volume 1, No. 1 , 2012
Publisher : Journal of Applied Chemical Science

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Abstract

The study of isolation and characterization of terpenoids in methanol extract from the stem bark of Grewia eriocarpa Juss has been conducted. The aims of the research were to know the kind of secondary metabolites, to isolate and characterize terpenoids contained in methanol extract from the stem bark of Grewia eriocarpa Juss. Maceration from 1500 gram of the stem bark powder used methanol as solvent gave 275 gram extract and there was further partitioned with petroleum ether, chloroform and water. The results of phytochemical test showed that the sample was positive for saponin, terpenoid, flavonoid and tannin. Methanol-water extract was separated with column chromathography by n-hexane:etyl acetat (1:3) as eluent and gave 6 groups of fraction. FT-IR analysis results for C fraction indicated several functional group namely OH, C=O, COOH, C-H aromatic, C=C, N-H . Based on the data of mass spectra could be estimated that the 15, 18, 20 and 27 peaks were sesquiterpenoid and the 43 peak was dyterpenoid.
Isolation and Characterization of Cinnamaldehyde Contained in Stem Barkof Cinanamon (Cinnamomumburmannii) Yublina O. Gelang; Theo da Cunha; Luther Kadang
Journal of Applied Chemical Science Volume 1, No. 1 , 2012
Publisher : Journal of Applied Chemical Science

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The research about isolation and characterization of cinnamaldehyde compund that implied in skin steam of cinnamon (Cinnamomum burmannii) was done. Isolation method that used in this research is steam distillation. Cinnamon oil that result from steam skin of cinnamon in this research was 1,2 g (0,012 %). Cinnamon oil then isollated with slim chromatographic method using eluen-n hexane and ethanol with comparison 9:1, 7:3, and 1:1. Characterization cinnamon oil using Infrared spectrophotometer (IR) analysis and Gas Chromatographic- Mass Spectrophotometer (GC-MS). The analyzed result of Infrared spectrophotometer (IR) is giving absorbtion at range 1730,03 cm-1 that be character of aldehida as basic design cinnamaldehyde, while the result of GC analyzed is getting cinamaldehyde concentration 2,37%.
Antioxidant Activities of Chloroform and Aqueous Fractions of Myrmecodia Pendenss Extract: A Preliminary Study Yohanes Buang; Ermelinda Noya; Pius D. Ola; Theo Da Cunha
Journal of Applied Chemical Science Volume 2, No. 1 , 2013
Publisher : Journal of Applied Chemical Science

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There have been elucidated the antioxidant activities of chloroform and aqueous fractions of methanol extracts isolated from myrmecodia pendenss. The study was firstly started by maceration of myrmecodia pendenss powder in certain quantity of pure methanol solvent and followed by gradual partition of the methanol extract with chloroform and distillated water and then purified with column chromatography. The chemical contents migrated into both those later solvents were detected by GC-MS and their functional groups were detected by FT-IR instruments. Thereafter, the antioxidant activities of the migrated compounds in each those solvents were determined using hydrogen peroxide protocol and the absorbance was measured at 240 nm. The ascorbic acid solution was used as control. The results showed that FT-IR spectrum showed methylene and ethene groups are existed within the compounds contained by the extracts as well as the hydroxyl, carbonyl, aromatic, and keton groups. Furthermore, the GC-MS spectrum indicated the compounds that are existed within the chloroform and the aqueous fractions of the extract. The average absorbances of compounds contained within the chloroform and aqueous fractions were 0.161 and 0.112, respectively, whereas that of the control was 0.085. Those absorbance data conclusively indicated that higher absorbance higher residue of chromophore content existed within the fraction and higher failures of hydroxylation reactions. It was however, the antioxidant activities of the aqueous fractions were higher than those of the chloroform fractions.
Antibacterial Activities of Ranting Patah Tulang (Euphorbia tirucalli) Extract: Short Communication Sesilia I. Napa; Theo Da Cunha; Yohanes Buang
Journal of Applied Chemical Science Volume 2, No. 1 , 2013
Publisher : Journal of Applied Chemical Science

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There have been studied the antibacterial activities of ranting patah tulang (euphorbia tirucalli) extracts against the growth of salmonella thyposa (gram negative) bacteria. The study was firstly started to isolate the antibacterial components of euphorbia tirucalli that was soluble in methanol. Thereafter, the methanol solvent was evaporated to yield powder and the powder was used to prepare the extract concentrations in each petri dish as of following levels that were 10.0, 15.0, 20.0, 25.0, 50.0, 80.0, and 100.0 %, respectively. The 0.0 % of euphorbia tirucalli extracts and 1.0 % of erythromycin in each petri dish served as the controls. The results showed that the clear zone of petri dish containing the bacteria and each those extracts were 36.7±5.8, 40.0±10.0, 43.3±5.8, 60.0±10.0, 66.7±5.0, 70.0±10.0, and 76.7±5.8 mm, respectively. The clear zone of both those controls containing the bacteria were 63.3±5.8 mm. Those results indicate that higher extract concentration higher the clear zone area of the petri dish. Therefore, the euphorbia tirucalli extract potentially inhibits the growth of the salmonella thyposa (gram negative) bacteria.
PENGARUH PANJANG SERAT TERHADAP SIFAT BENDING PAPAN KOMPOSIT POLIESTER BERPENGUAT SERAT BUAH LONTAR Kristomus Boimau; Theo Da Cunha
ROTOR 2016: ROTOR Special Edition
Publisher : Jurusan Teknik Mesin Fakultas Teknik Universitas Jember

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Abstract

The need for wood as a building material is increasing, but the existing forest conditions are difficult to meet the demand. Several alternatives have been developed as an effort to overcome the lack of wood, for example by creating wood derivative products such as fiberboard, particle board, and cement board. The raw materials for making fiberboard usually use natural fibers derived from plants containing fibers such as kenaf, banana, hemp, sisal, lontar and flax. The prospect of fiberboard development is very potential, because Indonesia has a suitable climate overgrown by these fibrous plants.The purpose of this study is to determine the effect of fiber length on the bending properties of polyester composite board reinforced by palm fibers. The material used in this research is lontar fibers with fiber length 1 cm, 2 cm and 3 cm and polyester resin. Before the fiber is used as a reinforcing medium, the fibers are first treated with 5% alkali by soaking for 1 hour. After the fibers were removed, then rinsed with clean water to free the fiber from alkali and then dried. The ratio of fiber-matrix composition used in this study was adjusted to the rule of mixture (ROM), wherein the volume fraction of fiber (Vf) used was 30%. The composite board is made by hand-lay-up method and continued with 24 hours by pressing with hydraulic jack. Furthermore, the molded composite is cut into bending test specimen according to ASTM D790 standard. The nature of bending of composite board is known through the process of testing three point bending by using universal testing machine.The result of bending test shows that the test specimen with 3 cm fiber length has a higher bending strength value of 18.42 Mpa, while the composite with 2cm fiber length is 16.35 Mpa and 15,44 Mpa for 1cm fiber length. Keywords: composite, lontar fiber, fiber length, bending
PEMURNIAN MINYAK GENOAK ( Acorus calamus ) ASAL PULAU TIMOR MENGGUNAKAN DISTILASI PENGURANGAN TEKANAN Rensy A. Henci; Reinner I Lerrick; Theo Da Cunha
Saintek Lahan Kering Vol 3 No 1 (2020): JSLK JUNI 2020
Publisher : Fakultas Pertanian, Universitas Timor

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (408.352 KB) | DOI: 10.32938/slk.v3i1.1039

Abstract

A research about Asaron oil purification produced over Stahl distillation has been done. This research was conducted by distillation of genoak’s roots, rhizomes and laeves whilist the purification was carried out through reduced pressure distillation. A yellowish oil was yield respectively 1,83 gram from the roots and rhizomes and 1,26 gram from laeves which the was revealed as 90,49% pure of asaron confirmed by GC-MS, 1H-NMR and FT-IR analysis.
Co-Authors Alethia E. Siahainenia Ermelinda Noya Kristomus Boimau Luther Kadang Pius Dore Ola Reinner Ishaq Lerrick Rensy A. Henci Sesilia I. Napa Theodore Y. K. Lulan Yakoba Tari Yohanes Buang Yohanes Buang Yublina O. Gelang