Makara Journal of Science
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Diversity and the Composition of Fatty Acids of Lipolytic Bacteria Isolated from Soil and Aquatic Sediment in a Forest and on an Oil Palm Plantation
No full textThe specific bacteria in forests and on oil palm plantations are lipolytic bacteria. Their enzymes have been applied in the agro-aquaculture, food, detergent, pharmaceutical, dairy, and biodiesel-biokerosene industries. This study describes the diversity of cultivable lipolytic bacteria from soil and aquatic sediment in a forest and on an oil palm plantation and their fatty acid products. Soil samples used in this research were obtained from topsoil in a lowland forest and on an oil palm plantation and from sediments in fresh water near these sites. The forest is located in Bukit Duabelas National Park, and the oil palm plantation is near the forest in Sarolangun District, Jambi Province, Indonesia. Twenty-two isolates of lypolitic bacteria were selected from 32 isolates grown in lipolytic selective medium. The 22 consisted of 11 isolates from topsoil and 11 from aquatic sediment from the forest and plantation area. These isolates were identified by 16S rRNA-sequence data analysis. Taxonomically, they belonged to five genera: Burkholderia, Cupriavidus, Serratia, Acinetobacter, and Kurthia. The maximum likelihood tree showed that they are phylogenetically distributed in three clusters. They were clustered into three groups: the Burkholderia-Cupriavidus group, the Serratia-Acinetobacter group, and the Kurthia group. Their lipolytic enzymes formed various fatty acids after analysis by gas chromatography-flame ionization detector (GC-FID). Some isolates formed essential fatty acids, such as linoleic, linolenic, arachidonic, eicosapentanoic acid (EPA), and docosahexanoic acid (DHA)
The Use of Carbon Dioxide Released from Coconut Shell Combustion to Produce Na2CO3
No full textIn this investigation, sodium carbonate (Na2CO3) was produced by reacting the CO2 released from coconut shell combustion with NaOH solution with molar concentrations of 6.5, 7.0, 7.5, and 8.0 M. The main purpose of the study was to assess the potential of the proposed method for mitigation of the CO2 gas released into the atmosphere by the coconut shell industry. The Na2CO3 powder produced was oven-dried at 110 oC and subsequently characterized using FTIR, XRD, and SEM/EDS techniques. Thermal analysis was also carried out using DTA/TGA to investigate the thermal mechanisms of sodium carbonate formation. The experimental results show that the concentration of NaOH influences the mass of sodium carbonate produced, with the highest mass of 190.6 g obtained using 7.0 M NaOH solution. The FTIR analyses show the existence of O-H, C-O, C=O, and CO3-2, confirming the formation of Na2CO3. The C-S functional group was also detected most likely due to the presence of the sulfur that naturally exists in the coconut shell. The formation of Na2CO3 is also supported by the presence of C, Na, and O on the EDS results and the presence of the thermonatrite (Na2CO3.H2O) phase, as seen by the XRD. The XRD analysis of the sintered sample at 450 oC indicates the transformation of thermonatrite into sodium carbonate and sodium oxide, which is in accordance with the results of DTA/TGA analysis. Based on the results obtained, it is concluded that the proposed method can be applied to mitigation of CO2 gas released by the coconut shell industry
Micromagnetic Simulation of the Depinning Field Domain Wall on Symmetric Double Notch Ferromagnetic Wires
No full textIn this paper, we investigate the depinning field domain wall on symmetric double notch ferromagnetic wires by means of micromagnetic simulation for Permalloy (Py), Cobalt (Co), and Nickel (Ni) materials. The depinning field domain wall increases as the size of the notch decreases. At a lower depinning field, the domain wall inner structure exhibited a transverse wall (TW), while at a higher depinning field, there was a transformation of the domain wall inner structure from transverse wall to antivortex wall (AVW). We also observed that the magnetization energy increased as the size of the notch decreased. This means that more energy was needed to release the domain wall from a smaller notch. Micromagnetic simulation showed that the depinning field domain wall depends on the size of the notch and on the ferromagnetic anisotropy
One-Pot Transformation of (R)-(+)-Citronellal over a Bifunctional Ni/ZnBr2/β-Zeolite Catalyst
No full textAbstract The transformation of (R)-(+)-citronellal to isopulegols and menthols in a one-pot reaction was improved using a zeolite catalyst. The one-pot transformation of (R)-(+)-citronellal was studied through a Ni/ZnBr2/β-zeolite catalyst. The Ni/ZnBr2/β-zeolite catalyst was prepared by impregnating 15% ZnBr2 (w/w) and 15% Ni (w/w) on β-zeolite. The addition of Ni to the ZnBr2/β-zeolite catalyst resulted in a useful bifunctional catalyst that combined a high rate of cyclization of citronellal to isopulegols over ZnBr2 sites and subsequent hydrogenation to menthol over Ni sites. These catalysts were characterized using X-ray diffractometer (XRD) and scanning electron microscope-energy dispersive X-ray spectrometer (SEM-EDX). Catalytic reactions were carried out at 120 ºC with magnetic stirring under a 1 atm nitrogen atmosphere for 1 h (cyclization reaction) and maintained under a 1 atm hydrogen atmosphere for 4 h (hydrogenation reaction). Products of the reaction were measured using gas chromatography-mass spectrometer (GC-MS) and gas chromatography (GC). The results showed that the Ni/ZnBr2/β-zeolite catalyst can transform (R)-(+)-citronellal to isopulegols and menthols in a one-pot transformation, with a selectivity to isopulegols of 73.8% and selectivity to menthols of 6.40%. Abstrak Transformasi Satu Tahap (R)-(+)-Sitronelal Menggunakan Katalis Dwi Fungsi Ni/ZnBr2/β-zeolit. Transformasi satu tahap (R)-(+)-sitronelal menjadi isopulegol dan mentol dapat dilakukan dengan katalis berbasis zeolit. Pada penelitian ini dilakukan transformasi satu tahap (R)-(+)-sitronelal menggunakan katalis Ni/ZnBr2/β-zeolit. Katalis Ni/ZnBr2/β-zeolit dibuat dengan metode impregnasi 15% ZnBr2 (b/b) dan 15% Ni (b/b) pada β-zeolit. Penambahan Ni pada katalis ZnBr2/β-zeolit bertujuan untuk membentuk katalis dwi fungsi yang menggabungkan situs ZnBr2 untuk siklisasi sitronelal menjadi isopulegol yang dilanjutkan hidrogenasi isopulegol membentuk mentol melalui situs Ni. Katalis dikarakterisasi menggunakan X-Ray diffractometer (XRD) dan scanning electron microscope-energy dispersive X-ray spectrometer (SEM-EDX). Reaksi katalitik (R)-(+)-sitronelal dilakukan pada temperatur 120 ºC dengan pengadukan magnet dalam kondisi atmosfer gas nitrogen selama 1 jam (reaksi siklisasi) kemudian dilanjutkan pada atmosfer gas hidrogen selama 4 jam (reaksi hidrogen). Produk reaksi dianalisis menggunakan kromatografi gas-spektrometer massa (KG-SM) dan kromatografi gas (KG). Hasil penelitian menunjukkan bahwa katalis Ni/ZnBr2/β-zeolit dapat mentransformasi (R)-(+)-sitronelal menjadi isopulegol dan mentol dalam satu tahap, dengan selektivitas terhadap isopulegol sebesar 73,8% dan selektivitas terhadap mentol sebesar 6,40%. Keywords: citronellal, isopulegols, menthols, one-pot transformation, zeolite catalys
Detection of Papua New Guinea Thalassemia Alpha Mutation in Gayo, Sumba, Ternate, and Timika Populations
No full textAbstract Papua New Guinea (PNG) mutation is a point mutation that occurs in noncoding region of alpha globin clusters. Polymorphism promotes an additional recognition site for transcription factor (GATA-1) which presumably downregulates alpha globin synthesis. The aim of this research is to detect PNG mutation in other populations in Indonesia, thus the results will be used for completing standard diagnoses in detecting alpha thalassemia mutation based on ethnic background. The method used in detecting PNG mutation was PCR-RFLP. Detection of 399 samples (MCH <80 fL) using the PCR-RFLP method showed positive results for the Timika population. However, negative results were found in the Gayo, Sumba, and Ternate populations. PNG mutation frequency in the Timika (Papuan ethnic) population is 18.1% (28 of 154 samples). High malaria prevalence in East Indonesia did not show a positive correlation with the absence of PNG mutation in the Sumba and Ternate populations. The results showed that PNG mutation is only found groups that are infected with Plasmodium falciparum malaria, but not in Plasmodium vivax-infected ones. However, PNG mutation is common in the eastern Indonesia population. Abstrak Deteksi Mutasi Papua Nugini (PNG) Thalassemia Alfa di Populasi Gayo, Sumba, Ternate, dan Timika. Mutasi PNG merupakan mutasi titik di luar gugus globin alfa. Polimorfisme menyebabkan terbentuknya promoter baru sebagai situs pengikatan faktor transkripsi GATA-1 yang diduga menurunkan laju transkripsi normal globin alfa. Tujuan dari penelitian ini adalah untuk mengetahui keberadaan mutasi PNG di populasi lain di Indonesia, sehingga hasil penelitian ini dapat digunakan untuk melengkapi standar diagnosis dalam mendeteksi mutasi penyebab thalassemia alfa berdasarkan latar belakang etnik. Teknik yang digunakan dalam mendeteksi mutasi PNG adalah PCR-RFLP. Hasil menunjukkan 18,1% (28 dari 154 sampel) positif pada populasi Timika, namun hasil negatif ditunjukkan pada semua sampel DNA populasi Gayo, Sumba, dan Ternate. Prevalensi malaria yang tinggi di wilayah Indonesia Timur tidak menunjukkan korelasi positif terhadap keberadaan mutasi PNG di populasi Sumba dan Ternate. Hasil penelitian menunjukkan bahwa mutasi PNG ditemukan hanya pada kelompok individu yang terinfeksi Plasmodium falciparum tetapi tidak pada kelompok individu yang terinfeksi Plasmodium vivax dan mutasi PNG juga ditemukan pada satu individu beretnik Ambon yang tinggal di Timika.  
Isolation, Purification, and Characterization of Antimicrobial Substances from Endophytic Actinomycetes
No full textAbstract Antimicrobial active substances produced by endophytic actinomycetes were isolated and purified. Plant samples were obtained from four different medicinal plants namely Curcuma domestica, Phaleria macrocarpa, Isotoma longiflora, and Symplocos cocchinensis. Isolation of actinomycetes was conducted using HV agar with the addition of cycloheximide, nystatin, nalidixic acid, and rifamycin. A total of 21 actinomycete isolates were obtained and tested for antimicrobial activity against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC25923, Pseudomonas aeruginosa ATCC27853, and Bacillus subtilis ATCC 66923. Among the isolates, isolate KY01 was the most active to Gram-positive and Gram-negative bacteria. Morphological observation and identification using 16S rRNA gene sequence showed that the isolate KY01 was similar to Streptomyces antibioticus. An active compound from the isolate KY01 was produced using yeast peptone medium. The active compound was purified using silica-gel-column chromatography and preparative high performance liquid chromatography (HPLC). A single peak of the active compound was detected with HPLC and LCMS, which showed a retention time of 26.6 min and molecular weight (MW) 906.4474 g/mol, respectively. Abstrak Isolasi, Purifikasi, dan Karakterisasi Senyawa Antimikroba dari Aktinomisetes Endofit. Isolasi dan purifikasi senyawa aktif anti mikroba yang dihasilkan oleh aktinomisetes endofit telah dilakukan. Sampel tanaman diperoleh dari empat jenis tanaman obat yaitu Curcuma domestica, Phaleria macrocarpa, Isotoma longiflora, dan Symplocos cocchinensis. Isolasi aktinomistes endofit dilakukan dengan menggunakan medium HV agar dengan penambahan antibiotik sikloheksimida, nistatin, asam nalidik, dan rifamisin. Sebanyak 21 isolat aktinomisetes diperoleh dari sampel tanaman obat yang selanjutnya diuji aktivitas antimikroba terhadap Escherichia coli ATCC 25922, Staphylococcus aureus ATCC25923, Pseudomonas aeruginosa ATCC27853, dan Bacillus subtilis ATCC 66923. Hasil pengujian pada 21 isolat yang diperoleh, isolat KY01 menunjukkan aktivitas antimikroba paling kuat terhadap bakteri Gram-positif maupun bakteri Gram-negatif. Pengamatan secara morfologi dan identifikasi menggunakan sequence gen 16 rRNA menunjukkan bahwa isolat KY01 memiliki kemiripan dengan Streptomyces antibioticus. Produksi senyawa aktif isolat KY01 dengan kultur cair menggunakan medium yeast pepton. Purifikasi senyawa aktif dari ekstrak fermentasi dilakukan menggunakan kromatografi kolom silica gel dan HPLC preparatif. Hasil identifikasi menggunakan HPLC menunjukkan puncak dengan waktu retensi 26,6 menit dan hasil karakterisasi senyawa aktif menggunakan LCMS menunjukkan bobot molekul senyawa aktif sebesar (MW) 906,4474 g/mol. Keywords: endophytic actinomycetes, isolation, screening, antimicrobial activity, purificatio
Construction and Characterization of Conductometric Biosensor for Determination of the Diazinon Concentration
No full textAbstract Excessive diazinon residue in vegetables can endanger human health. Therefore, a simple, fast, and accurate method is needed to detect residue. A conductometric biosensor is a good choice because it also offers high selectivity and sensitivity. The principle of detection of the conductometric biosensor is based on enzymatic hydrolysis of diazinon into O,O diethyl phosphorothiate,2-isopropyl-6-methylpyrimidin-4-ol, and H+ catalyzed by organophosphate hydrolase (OPH). The optimum amount of organophosphate hydrolase added to the screen-printed carbon electrode (SPCE) modified with BSA-glutaraldehyde is 118.5 µg, while the optimum pH is 8.5. This biosensor has a response time of 30 sec, a linear dynamic range of 0 to 1 ppm, sensitivity of 42.21 µS/ppm, and limit of detection of 0.19 ppm. Abstrak Pembuatan dan Karakterisasi Biosensor Konduktometri untuk Penentuan Konsentrasi Diazinon. Residu diazinon yang berlebihan pada sayur-sayuran dapat membahayakan kesehatan manusia. Oleh sebab itu, diperlukan suatu metode yang sederhana, cepat, dan akurat untuk menentukan kadar residu diazinon tersebut. Salah satu pilihan yang tepat adalah biosoensor konduktometri karena biosensor ini juga menawarkan kepekaan dan selektifitas yang tinggi. Prinsip deteksi dari biosensor konduktometri didasarkan pada pengukuran daya hantar larutan hasil hidrolisis diazinon menjadi O,O dietil fosforotioat, 2-isopropil-6-metilpirimidin-4-ol dan H+ yang dikatalisis oleh enzim organofosfat hidrolase (OPH). Jumlah enzim optimum yang ditambahkan pada SPCE yang dimodifikasi oleh BSA-glutaraldehida adalah 118,5 µg, sementara pH kerja optimum adalah 8,5. Biosensor ini memiliki waktu respon 30 detik, kisaran konsentrasi linier 0 hingga 1 ppm, kepekaan 42,21 µS/ppm dan batas deteksi 0,19 ppm.  
Synthesis of Tris(4-Methoxyphenyl)Phenylsilane Using Phenylsilane and 4-Iodo Anisole Catalyzed by Palladium Complex
No full textAbstract The synthesis of tris(4-methoxyphenyl)phenylsilan through the coupling reaction of phenylsilane and 4-iodoanisole using palladium tertiary tributylphosphine as a catalyst was carried out through the determination of the base, solvent, and reaction time. The results showed that tris(4-methoxyphenyl)phenylsilane can be synthesized to form maximum yield using 1,4-diazabicyclo[2,2,2]octane (DABCO) as a base, tetrahydrofuran as a solvent, and a 5-day reaction time. The highest yield of tris(4-methoxyphenyl)phenylsilane was 35%. Abstrak Sintesis Tris(4-Metoksifenil)Fenilsilan Menggunakan Fenilsilan dan 4-Iodida Anisol dengan Katalis Senyawa Kompleks Paladium. Sintesis tris(4-metoksifenil)fenilsilan melalui reaksi kopling antara fenilsilan dan 4-iodida anisol menggunakan senyawa paladium tersier tributilfosfin sebagai katalis telah dilakukan berdasarkan penentuan senyawa basa, pelarut, dan waktu reaksi kopling. Hasil penelitian menunjukkan bahwa senyawa tris(4-metoksifenil)fenilsilan dapat disintesis menghasilkan persentase produk maksimum pada penggunaan senyawa 1,4-diazabisiko[2,2,2]oktan (DABCO) sebagai basa, tetrahidrofuran sebagai pelarut, dan waktu reaksi kopling selama 5 hari. Persentase tertinggi produk senyawa tris(4-metoksifenil)fenilsilan adalah 35%
Detection of Submicroscopic Soil-Transmitted Helminth Infections from Fecal Samples in Nangapanda, Ende, Using Real-Time Polymerase Chain Reaction
No full textAbstract Soil-transmitted helminth (STH) infections (Necator americanus (hookworm), Ancylostoma duodenale (hookworm), and Ascaris lumbricoides) can lead to anemia, malnutrition, and iron deficiency. Traditionally, STH infections have been diagnosed using microscopy to detect eggs in human fecal samples. However, there are several limitations of this method. The aim of this research was to detect the percentage of submicroscopic STH infections from human fecal samples (children, 5–18 years old) in Nangapanda, Ende, using the real-time polymerase chain reaction (PCR) method. The fecal samples were collected in two time periods, which were before and after treatment, using 400 mg of Albendazole. There were 242 samples in total, but only 45 negative samples from microscopic detection were tested with real-time PCR. The DNA samples were isolated and amplified wih primers of internal transcribed spacer (ITS-1 and ITS-2) region of rDNA. The detection of samples with real-time PCR generated an amplification curve in VIC, FAM, and Texas Red fluorophore. Three samples (6.7%) in pre-treatment were low load of DNA (N. americanus and A. lumbricoides) (Ct > 35). Four samples (9.1%) were low load of DNA (N. americanus) (Ct > 35) in post-treatment. Five samples (11.4%) were moderate load of DNA (A. lumbricoides) (30 < Ct < 35) in post-treatment. This study showed that real-time PCR could detect submicroscopic infections from specific species of hookworm and A. lumbricoides. Abstrak Deteksi Infeksi Submikroskopis Necator americanus, Ancylostoma duodenale, dan Ascaris lumbricoides dari Sampel Feses di Nangapanda, Ende, Menggunakan Real-Time Polymerase Chain Reaction. Infeksi dari Soil-Transmitted Helminthes (STH) (N. americanus, A. duodenale (Hookworm), dan A. lumbricoides) dapat menyebabkan anemia, kekurangan zat besi, bahkan malnutrisi. Pemeriksaan infeksi STH dapat dilakukan menggunakan mikroskop, tetapi metode tersebut masih kurang sensitif. Penelitian bertujuan mendeteksi dan mengetahui persentase infeksi submikroskopis STH dari sampel feses anak (usia 5-18 tahun) di Nangapanda, Ende menggunakan metode real-time polymerase chain reaction (PCR). Sampel feses dikoleksi sebanyak dua kali, yaitu sebelum dan sesudah pemberian albendazole 400 mg. Total sampel yang diperoleh adalah 242 tetapi hanya 45 sampel yang negatif secara mikroskopis yang diuji dengan real-time PCR. DNA sampel diisolasi dan diamplifikasi menggunakan primer dari daerah internal transcribed spacer (ITS-1 dan ITS-2) rDNA. Deteksi dengan real-time PCR menghasilkan kurva amplifikasi pada fluorophore VIC, FAM, dan Texas Red. Sebanyak tiga sampel (6,7%) pada pre treatment termasuk low load of DNA (N. americanus and A. lumbricoides) (Ct > 35), empat sampel (9,1%) termasuk low load of DNA untuk N. americanus saja (Ct > 35), dan lima sampel (11,4%) termasuk moderate load of DNA untuk A. lumbricoides saja (30 < Ct < 35) pada post treatment. Hasil penelitian menunjukkan bahwa real-time PCR dapat mendeteksi infeksi submikroskopis dari Hookworm dan A. lumbricoides
Sansevieria trifasciata Properties as Lead(II) Ion Biosorbent
No full textAbstract Sansevieria trifasciata (also called snake plant or mother in law’s tongue) is predicted to act as a heavy metal biosorbent. S. trifasciata was optimized as a biosorbent by using the response surface method with varying weights of S. trifasciata, pH of Pb (II) solutions, contact times, and temperatures. The ion concentration before and after biosorption was measured with an atomic absorption spectrophotometer (AAS). The optimum biosorption conditions were pH 7, 240 min contact time, and 1.5 g biosorbent with biosorption capacity of Pb (II) ions 0.725 mg/g. The biosorption isotherm analysis showed that the biosorption is consistent with the Freundlich isotherm model. The peak intensity of the FTIR spectrum of S. trifasciata after treatment with Pb (II) was around 2130/cm. The S. trifasciata micrograph showed a porous structure with non-uniform pore sizes. The biosorption of Pb (II) ions on powdered S. trifasciata leaves was found with the SEM EDX analysis. It is concluded from this research that S. trifasciata can be used as a biosorbent to remove Pb ion contamination. Abstrak Biosorpsi Ion Timah Hitam (II) Menggunakan Sansevieria trifasciata Prain. Sansevieria trifasciata (yang dikenal sebagai tumbuhan ular atau lidah mertua) diduga dapat menjadi biosorben logam berat. Konsentrasi ion logam Pb (II) sebelum dan sesudah biosorpsi diukur dengan spektrofotometer serapan atom (SSA). Optimasi kemampuan S. trifasciata sebagai biosorben dilakukan menggunakan metode respon surface dengan variasi pada massa tumbuhan, pH larutan, waktu kontak, dan suhu. Kondisi biosorpsi optimal diperoleh pada pH 7, waktu 240 menit dan berat S. trifasciata 1.5 g dengan kapasitas biosorpsi Pb (II) sebesar 0.725 mg/g. Analisis isoterm adsorpsi menunjukkan biosorpsi mengikuti model isotherm Freundlich. Spektrum FTIR daun lidah mertua setelah diperlakukan larutan timah hitam (II) memperlihatkan intensitas puncak pada daerah 2130/cm. Mikrograf daun lidah mertua memperlihatkan struktur berpori dengan ukuran yang tidak seragam. Penyerapan Pb (II) pada serbuk daun S. trifasciata diketahui melalui analisis SEM EDX. Berdasarkan hasil penelitian, dapat disimpulkan bahwa S. trifasciata dapat digunakan sebagai biosorben untuk menghilangkan kontaminasi ion Pb.