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All Journal Journal of Applied Chemical Science JMM (Jurnal Masyarakat Mandiri) Jurnal Fisika : Fisika Sains dan Aplikasinya BIO-EDU: Jurnal Pendidikan Biologi Jurnal Ilmiah Berkala Sains dan Terapan Kimia Chemistry Notes
Theodore Y. K. Lulan
Department Of Chemistry Faculty Of Science And Engineering, Nusa Cendana University
Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Earth & Planetary Sciences Education Electrical & Electronics Engineering Energy Environmental Science Materials Science & Nanotechnology Physics Social Sciences Other

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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.
The Activated Charcoal of Hazelnut Shell (Aleurites moluccana) Has Potential Capability to Refining Used Cooking Oil Desiana Sanang; Luther Kadang; Theodore Y. K. Lulan
Journal of Applied Chemical Science Volume 1, No. 1 , 2012
Publisher : Journal of Applied Chemical Science

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Abstract

The research that aims to determine the ability of chandlenut shell activated carbon as adsorbent on purification adible frying oil has been done. Frying oil purification process includes of the removal phase seasoning (despicing), neutralization and bleaching using activated carbon. The results showed that the optimum amount of chandlenut shell activated carbon which interacted with adible frying oil on purification process at 0,75 grams, effectively lowering the acid value (0,2984 mg KOH / g), peroxide value (3,2847 meq / Kg), water content (0,1468%) and free fatty acid levels (0,1261%), and increasing numbers saponification (196,2711 mg KOH / g) and also clear oil. However, peroxide value and oil colors result of interacted with the chandlenut shell activated carbon, do not meet the National Standard of Indonesia.
Produksi Biodiesel dari Minyak Biji Jarak Pagar (Jatropha curcas L.) Kolo, Sefrinus M.D.; Siburian, Rikson A.F; Lulan, Theodore Y.K
BIO-EDU: Jurnal Pendidikan Biologi Vol 1 No 1 (2016): Jurnal BIO-EDU Volume 1 Nomor 1 Tahun 2016
Publisher : Jurusan Pendidikan Biologi, Fakultas Ilmu Pendidikan, Universitas Timor

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Abstract

Penelitian tentang pengaruh variasi konsentrasi metanol terhadap sifat fisika-kimia biodiesel dari minyak biji jarak pagar (Jatropha curcas L.) telah dilakukan. Tujuan penelitian ini adalah untuk mengetahui pengaruh variasi konsentrasi metanol terhadap sifat fisikakimia biodiesel dan menentukan konsentrasi efektif metanol pada pengujian sifat fisika-kimia biodiesel. Pembuatan biodiesel dilakukan dengan proses esterifikasi dan transesterifikasi. Sifat fisika-kimia yang diuji dalam penelitian ini yaitu: kerapatan, kekentalan dan bilangan asam. Hasil penelitian menunjukkan adanya pengaruh variasi konsentrasi metanol terhadap sifat fisika-kimia biodiesel dimana proses esterifikasi dan transesterifikasi mampu mengkonversi asam lemak bebas dan trigliserida menjadi metil ester. Analisis keragaman dan uji BNT menunjukkan konsentrasi efektif metanol untuk meningkatkan mutu biodiesel yaitu 30 % dengan kerapatan sebesar 0,8802 mg/l dan bilangan asam sebesar 4,72 mg KOH/g serta kekentalan sebesar 6,32 mm2/s.
ADSORPSI ZAT WARNA NAPHTOL MENGGUNAKAN ADSORBEN KULIT BUAH KAKAO (Theobroma cacao L.) Novita Santalia Nika; Imanuel Gauru; Luther Kadang; Theodore Y. K. Lulan
Jurnal Fisika : Fisika Sains dan Aplikasinya Vol 7 No 1 (2022): Jurnal Fisika : Fisika Sains dan Aplikasinya
Publisher : Universitas Nusa Cendana

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Abstract

Abstrak Penelitian adsorpsi zat warna naphtol menggunakan adsorben kulit buah kakao (Theobroma cacao L.) telah dilakukan. Penelitian ini bertujuan untuk mengetahui karakteristik adsorben arang aktif kulit buah kakao (Theobroma cacao L.), mengetahui pengaruh pH, waktu kontak dan konsentrasi adsorpsi arang aktif kulit buah kakao (Theobroma cacao L.) terhadap zat warna naphtol dan mengetahui kapasitas adsorpsi arang aktif kulit buah kakao (Theobroma cacao L.) terhadap zat warna naphtol. Metode yang digunakan dalam penelitian ini adalah adsorpsi. Hasil yang diperoleh yaitu karakteristik dari adsorben arang aktif kulit buah kakao hasil analisis FTIR menunjukan bahwa adsorben kulit buah kakao teraktivasi HCL mengandung gugus fungsi –OH, C-H, CH2, C-O dan C=C aromatik, hasil analisis SSA diperoleh luas permukaan sebesar 178,10 m2/g, dengan volume pori sebesar 0,16 cc/g dan ukuran pori sebesar 1,80 nm. Kondisi optimum adsorben arang aktif kulit buah kakao terjadi pada pH 4, waktu kontak 90 menit dan konsentrasi 60 ppm. Kapasitas adsorpsi arang aktif kulit buah kakao dalam mengadsorpsi zat warna naphtol adalah sebesar 5,8651 mg/g. pola isoterm adsorpsi mengikuti isoterm langmuir dengan nilai R2 sebesar 0,8275 dan energi adsorpsi sebesar 25,627905 KJ/mol. Abstract Research on the adsorption of naphtol dyes using cocoa pods (Theobroma cacao L.) as an adsorbent has been carried out. This study aims to determine the characteristics of the adsorbent of activated charcoal cocoa pods (Theobroma cacao L.), determine the effect of pH, contact time and adsorption concentration of activated charcoal cocoa pods (Theobroma cacao L.) on naphtol dyes and determine the adsorption capacity of activated charcoal skins. cocoa pods (Theobroma cacao L.) against naphtol dyes. The method used in this research is adsorption. The results obtained are the characteristics of the activated charcoal adsorbent of cocoa pods. FTIR analysis results show that the adsorbent of activated cocoa pods HCL contains functional groups –OH, CH, CH2, CO and C=C aromatics, the results of SSA analysis obtained a surface area of ​​178.10 m2/g, with a pore volume of 0.16 cc/g and a pore size of 1.80 nm. The optimum condition of activated charcoal adsorbent of cocoa pods occurred at pH 4, contact time of 90 minutes and concentration of 60 ppm. The adsorption capacity of activated charcoal of cocoa pods in adsorption of naphtol dye was 5.8651 mg/g. The adsorption isotherm pattern followed the Langmuir isotherm with an R2 value of 0.8275 and an adsorption energy of 25.627905 KJ/mol.
Antioxidant and Antibacterial Activity of The Stem Bark Extract of Sterculia Foetida L. Theodore Yehezkiel Kristoferson Lulan; Febri Odel Nitbani; Reinner Ishaq Lerrick
Jurnal Sains dan Terapan Kimia Vol 16, No 2 (2022)
Publisher : Program Studi Kimia, Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/jstk.v16i2.12040

Abstract

Free radicals are compounds that contain one or more unpaired electrons which are very reactive, causing damage to cells or tissues and implication in the emergence of various degenerative diseases. Several methods of exploring medicinal plants have been carried out to find new sources of natural antioxidants and antibacterials that can reduce the use of synthetic drugs. This study aimed to examine the antioxidant and antibacterial activity of the stem bark extract of the plant Sterculia foetida L. The antioxidant activity of S. foetida was tested using the ABTS radical method (2,2-Azinobis 3-ethyl benzothiazoline 6-sulfonic acid). The principle of this method is that the color intensity or absorbance of the ABTS solution is inversely proportional to the concentration of antioxidant compounds. ABTS absorbance measurements were carried out at a wavelength of 734 nm. The results showed that the bark extract of the plant S. foetida could inhibit ABTS radicals with an IC50 value of 5.54 g/mL. The antibacterial activity of S. foetida was tested by measuring the optical density (OD) at a wavelength of 630 nm and expressed by the Inhibition Concentration 50 (IC50) value of 10442.29 g/mL.
Purification and Characterization of Silica Rice Husk Ash (Oryza Sative L.) From Kupang Regency Lede, Mega O. L.; Wogo, Hermania Em; Lulan, Theodore Y. K.; Ledoh, Sherlly M. F.
Chemistry Notes Vol 3 No (1) (2021): Chem. Notes 2021, 3(1)
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/cn.v3i(1).4745

Abstract

This research had been done to purify and characterize silica from rice husk ash for two varieties of rice from Kupang Regency. The purification method used is the extraction method with alkaline solution (NaOH) and precipitation with acid solution (H2SO4). The stages in this research were preparation of rice husk ash, purification of silica rice husk ash with NaOH and H2SO4 solutions, and characterization covered: determination of acidity and surface area and determination of composition using X-ray fluorescence spectrophotometer (XRF). The results of the surface acidity test showed that the highest acidity was in Ciherang silica from Tarus, which was 2.288 mmol/g. While the surface area test showed that the largest surface area was Inpari 46 silica from Pariti, which was 184.297 m2/g with an optimum contact time of 50 minutes. The results of characterization using XRF exhibited that the highest silica purity was Ciherang rice variety from Tarus, with initial silica content data, purification with NaOH and H2SO4 were 93.9%; 98.2% and 99.1%. So that the purification process with NaOH and H2SO4 is proven to increase the silica content in the sample.
Bioaktivitas Metabolit Sekunder dari Genus Dipterocarpus Nalle, Halena A.; Lulan, Theodore Y. K.; de Rozari, Philiphi; Ola, Antonius R. B.
Chemistry Notes Vol 4 No (1) (2022): Chem. Notes 2022, 4 (1)
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/cn.v3i2.6078

Abstract

Research has been conducted with the title "Literature Study of Secondary Metabolites and Bioactivity of Plants Genus Dipterocarpus". The method used is a descriptive method with the aim of being to find out the active compounds in the genus plant dipterocarpus and to know the ability of the bioactivity of genus plants dipterocarpus. Based on the results of the study, bioactivity of secondary metabolites from planst of the genus dipterocarpus namely antidiabetic, antiplasmodial, antibacterial, antioxidant, anticlasses, cytotoxic, anticholinesterase, antiproliferation, anti-inflammatory and antimicrobial. Very strong biosaltivity indicated by the ethyl acetate faction plant D. Intricatus Sagai Antioxidant IC50 Nialial is 0.075 μg / mL. While very weak bioacchables are shown extract methanol stem plant D. Costatus as cytotoxic with ic50 value 973 ± 14.57 μg / mL.
Pengaruh Komposisi Daun Gamal (Gliricidia sepium Hbr.) dan Kotoran Sapi dengan Nutrisi Pisang terhadap Rasio C/N Kompos Sedo, Karolina M.; Tawa, Bibiana Dho; Lulan, Theodore Y. K.; Gauru, Imanuel; Cunha, Theodorus M. Da
Chemistry Notes Vol 3 No 2 (2021): Chem. Notes 2021, 3(2)
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/cn.v3i2.6089

Abstract

It has been done a research on the effect of the composition of gliricidia sepium Hbr. And cow dung with banana nutrition on the composting process on the C/N ratio. This research was conducted with the aim of knowing the effect of the composition and the length of time required for fermentation. Composting was made with a variety of cow dung : gliricidia sepium Hbr. In a ratio of 1:9, 1:1, 3:2, 7:3, 9:1, and 2:3 in % by using 25% banana nutrition and 100% water from the total weight of the manure. On this research was found that the optimal time is on 14th day with characteristic of compost that was produced, equal with the the Indonesia National Standar (SNI Kompos 19-7030-2004). The conclusion is the compcsition of cow dung and Gliricidia sepium leaves did not significant affect to the C/N compost ratio.
Analisis Kualitas Air pada Sumber Mata Air Di Desa Baumata Kecamatan Taebenu Kabupaten Kupang Kadang, Luther; Nua, Maria F.; Lulan, Theodore Y. Y. K.
Chemistry Notes Vol 4 No 2 (2022): Chem. Notes 2022, 4 (2)
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/cn.v4i2.9510

Abstract

Water quality is the nature of water and the content of living this, substances, energy, or other components in water as seen from physical, chemical, and biological characteristics. Pollution of the water environment often occurs, there by reducing water quality. The purpose of this study was to determine the quality and status of contamination of springs based on physical, chemical, and biological parameters in Baumata Village, Taebenu District, Kupang Regency based on the storet method. Determination of the location of water sampling is determined by the purposive sampling technique, while the water sampling refers to the Indonesian National Standard (SNI). Water quality measurements where carried out in situ and ex situ. Parameters tested in situ were temperature, tds, pH, odor and taste, while ex situ were hardness, detergent, and total coliform. The data from the analysis were compared with the quality standars according to Permenkes No. 32 of 2017. The results of the research on spring were reviewed from the parameters of temperature, tds, odor, taste, pH, hardness, and detergent showed that each value was still within safe limits except for parameters total coliform because it exceeds the required quality standars. The status of water contamination in springs based on the STORET method is lightly polluted.
Pemanfaatan Silika Gel Hasil Pengolahan Abu Tongkol Jagung Termodifikasi TiO2 untuk Mengurangi Kadar Nitrat dalam Limbah Cair Tahu Lulan, Theodore Y. K.; Ndolu, Intan C. M.; Nitti, Fidelis
Chemistry Notes Vol 5 No 2 (2023): Chem Notes, 5(2), 2023
Publisher : Universitas Nusa Cendana

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Abstract

Research has been conducted with the title Utilization of Silica Gel from the processing of TiO2-Modified Corn Cob Ash to Reduce Nitrate Levels in Tofu Liquid Waste. This study aims to determine the characteristics of silica gel from the processing of TiO2-modified corn cob ash in terms of functional groups and crystallinity and to determine the effectiveness of TiO2-modified silica gel to reduce nitrate levels in tofu liquid waste using pH, time and concentration parameters. The synthesis of silica gel from corn cob ash was carried out using the sol gel method. The results of FTIR characterization showed the successful synthesis of silica gel and TiO2 modified silica gel indicated by the presence of Si-O-Si and Si-OH absorption in silica gel and Ti-O-Ti absorption in TiO2 modified silica gel. The XRD data shows that silica gel has an amorphous structure and modified silica gel has an anatase structure. The results showed that the largest nitrate reduction occurred at pH 5 by 98.69%, contact time of 60 minutes by 97.39% and optimum concentration of 200 ppm by 98.94% with the largest silica adsorption capacity of 245.94 mg/g and the percentage of nitrate reduction in tofu liquid waste by 99.94%.
Co-Authors Antonius R.B. Ola Asanab, Fitriani Bibiana D. Tawa Cunha, Theodorus M. Da Da Cunha, Theo Desiana Sanang Dodi Darmakusuma, Dodi Fidelis Nitti Gauru, Imanuel Hermania Em Wogo Kadang, Luther Lanamana, Willybrordus Laurentius Dominicus Gadi Djou Lede, Mega O. L. Ledoh, Sherlly M. F. Luther Kadang Murdaningsih Murdaningsih, Murdaningsih Nalle, Halena A. Ndolu, Intan C. M. Novita Santalia Nika Nua, Maria F. Philiphi de Rozari Reinner Ishaq Lerrick Rozari, Philipi D. Santos, Adelina Dos Sedo, Karolina M. Sefrinus Maria Dolfi Kolo Siburian, Rikson A.F Theo Da Cunha Yakoba Tari Yohanes Buang