Makara Journal of Science
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Effects of Nitrate and Salinity on Fatty Acid Composition of Marine Tetraselmis sp.: Potential as Biodiesel
No full textIdentifying sources of renewable energy is extremely important. The potential of Tetraselmis sp. in biodiesel production was investigated using a completely randomized design with four treatments. Tetraselmis sp. was cultured on media containing different concentrations of nitrate there are 2 mM and 15 Mm and s 25 ‰ and 35 ‰ salinity. The treatments namely are (N2S25), (N2S35), N15S25) and (N15S35). Analysis of the fatty acid content using gas chromatography-mass spectrometry (GC-MS). The results showed that the highest growth occurred in culture that contained 15 mM of nitrate and 35 ‰ salinity. The lowest growth occurred in culture containing 2 mM of nitrate and 25‰ of salinity. The highest lipid content was found in cultures containing 2 mM of nitrate and 25‰ salinity, it is 34.83%. Seven fatty acids were detected in culture containing 2 mM of nitrate and 25‰ salinity namely myristic acid (4.02%), palmitic acid (40.59%), palmitoleic acid (29.06%), stearic acid (0.95%), oleic acid (12.52%), gamma-linolenic acid (2.56%), and arachidonic acid (9.38%). Four fatty acids palmitoleic acid (8.99%), palmitic acid (37.34%), oleic acid(44.89%), and stearic acid (8.78%) were detected in 2 mM of nitrate with 35‰ salinity. The fatty acids have potential to be used as raw material for biodiesel production
Leaf Trichome Morphology of Durio Kutejensis Landraces from Kalimantan
No full textThe leaf trichome morphology of 19 Durio kutejensis (lai) landraces was studied. The observation of cross- and paradermal sections of D. kutejensis leaves showed that all landraces have glabrous leaves on the adaxial surface, while their abaxial surfaces are covered by six trichome types, one glandular (one- or two-celled stalks with a spheroid multicellular glandular head) and five non-glandular (complex peltate, simple peltate, cushioned stellate, flat stellate, and four-armed stellate trichome with a central cushion). All landraces were rarely covered by glandular trichomes. The non-glandular trichomes are varied in type, density, number of layers, diameter, and shape and margin color of the complex peltate among landraces. One landrace comprises three non-glandular trichome types, while the other landraces consist of four or five non-glandular trichome types. The shapes and margin color of complex peltate trichomes of D. kutejensis are the specific characteristics which distinguish this species from the other Durio species, however these characteristics cannot be used to differentiate one D. kutejensis landraces from the other. Therefore, other characteristics need to be explored in order to distinguish one D. kutejensis landraces from the other
Isolation of Pandangolide 1 from Cladosporium oxysporum, An Endophyte of the Terrestrial Plant Alyxia reinwardtii
No full textPandangolide 1 was isolated from the ethyl acetate extract of Cladosporium oxysporum cultures. The fungus was originally obtained from Alyxia reinwardtii. The structure of pandangolide 1 was elucidated on the basis of nuclear magnetic resonance (NMR) spectroscopy and accurate mass spectrometric data. This is the first report of the isolation of pandangolide 1 from endophytic C. oxysporum derived from a terrestrial host plan
Flavonoid Compounds from the Bark of Aglaia eximia (Meliaceae)
No full textThree flavonoid compounds, kaempferol (1), kaempferol-3-O-α-L-rhamnoside (2), and kaempferol-3-O-β-D-glucosyl-α-L-rhamnoside (3), were isolated from the bark of Aglaia eximia (Meliaceae). The chemical structures of compounds 1–3 were identified with spectroscopic data, including UV, IR, NMR (1H, 13C, DEPT 135°, HMQC, HMBC, 1H-1H-COSY NMR), and MS, as well as a compared with previously reported spectra data. All compounds were evaluated for their cytotoxic effects against P-388 murine leukemia cells. Compounds 1–3 showed cytotoxicity against P-388 murine leukemia cells with IC50 values of 1.22, 42.92, and >100 mg/mL, respectivel
A Simple and Safe Spectrophotometric Method for Iodide Determination
No full textIn order to practice green chemistry, a simple and safe spectrophotometric method for iodide determination has been successfully developed based on the formation of a blue starch-iodine complex. Iodide was oxidized to form iodine prior to the addition of a starch solution, and the blue starch-iodine complex was directly detected spectrophoto-metrically at a wavelength of 615 nm. The chemical parameters, such as type, reaction time, as well as concentration of oxidizing agents and solution pH were optimized with respect to sensitivity and analysis time. The method showed optimum results under iodate oxidant with a mol ratio of IO3-:I- =1:3, reaction time of 5 minutes, and solution pH of 5. Under these optimum conditions, the method showed linierity measurements from 5-40 mg/L iodide with a correlation (R2) of 0.9889. This technique offers a simple, safe, accurate, and relatively fast method for iodide determination, which is prospective for monitoring iodide samples. 
Microfungi on Leaves of Licuala bidentata (Arecaceae) from Sarawak, Malaysia
No full textA microfungal survey was carried out on the living leaves and litters of Licuala bidentata in Kubah National Park in Sarawak, Malaysia. A total of 400 leaf segments (200 segments for each leaf type) were plated on two isolation media (water agar and malt extract agar) for endophytic and saprophytic fungal isolation. Forty-three microfungal species were obtained from both leaf types, 31 species identified from living leaves and 18 species from litters. Only six species were common to both leaf types, with 25 and 12 species exclusively identified from living leaves and litters, respectively. New records of fungi from this host plant and for the genus Licuala include Isthmotricladia laeensis, Chloridium sp., Mucor sp., Oidiodendron sp., Kinochaeta sp., Cryptophiale sp., Chrysosporium merdarium and Circinotrichum fertile. This study constitutes the first report on microfungal community on L. bidentata. Implications of this new report in comparison with the microfungal species on other plant species in the genus Licuala are discussed
Isolation and Identification of Airborne Bacteria Inside Swiftlet Houses in Sarawak, Malaysia
No full textAbstract Air consists of such microorganisms as bacteria, fungi, and viruses. Exposure to these airborne bacteria indoors may cause infectious and noninfectious adverse health effects. However, the sources and origins of bacteria are not fully understood. The aim of this study was to isolate and identify the bacteria present in the air inside swiftlet houses located in Kota Samarahan, Saratok, Betong, Maludam, Miri, Kuching, Semarang, Sepinang, Sarikei, and Sibu in Sarawak, Malaysia. A total of 100 bacterial isolates from 20 samples were collected from swiftlet houses. The bacteria present in the air were collected using Plate Count Agar. Two plates were exposed at the front and back inside swiftlet houses for 15 sec and then incubated at 37 ± 1 oC for 24 h. The 16S rRNA analysis method was used to identify the isolates from the samples. The air inside the swiftlet houses had a total mean airborne bacteria colony count of 2.02 ± 0.72 log10 cfu/m2/sec; the highest was in Miri (3.08 ± 0.29 log10 cfu/m2/sec), and the lowest was in Sibu (1.05 ± 0.85 log10 cfu/m2/sec). Twenty-seven bacteria species were identified, and Lysinibacillus sp. B4 (16%) was most frequently isolated. Abstrak Isolasi dan Identifikasi Bakteri yang terdapat di Udara dalam Rumah Walet di Sarawak, Malaysia. Udara mengandung mikroorganisme seperti bakteri, jamur , dan virus. Paparan bakteri di udara dapat menyebabkan efek kesehatan yang merugikan. Namun, sumber dan asal bakteri tidak sepenuhnya dipahami. Tujuan dari penelitian adalah mengisolasi dan mengidentifikasi bakteri yang terdapat di udara di dalam rumah-rumah walet yang terletak di Kota Samarahan, Saratok, Betong, Maludam, Miri, Kuching, Semarang, Sepinang, Sarikei dan Sibu di Sarawak, Malaysia. Sebanyak 100 isolat bakteri dari 20 sampel diperoleh dari rumah-rumah walet. Bakteri diisolasi menggunakan medium Plate Count Agar. Sebanyak dua cawan petri dibuka di bagian depan dan belakang dalam rumah walet selama 15 detik, dan diinkubasi pada suhu 37±1 oC selama 24 jam. Sequencing DNA gen 16S rRNA dilakukan untuk mengidentifikasi bakteri dari sampel. Udara di dalam rumah walet memiliki total rata-rata jumlah koloni 2.02±0.72 log10 cfu/m2/detik dan CFU tertinggi diperoleh dari Miri (3.08 ± 0.29 log10 cfu/m2/detik) dan terendah di Sibu (1.05 ± 0.85 log10 cfu/m2/detik). Terdapat 27 species bakteri dari udara dalam ruangan di rumah walet, dan Lysinibacillus sp. (16%) paling banyak ditemukan. Keywords: Swiftlet house, Air samples, Bacteria, Identification, 16S rRNA gen
Molecular Markers Application for Blast Resistance Selection on the Double Haploid Rice Population
No full textBlast disease, caused by fungal Pyricularia grisea Sacc., is one of the most devastating diseases in rice. The use of blast-resistant rice varieties is one of the most efficient ways to control blast disease in rice. Blast-resistant varieties can be produced through breeding. The use of marker-assisted selection (MAS) available to support selection of resistant lines based on resistance gene. The objective of this research was to compare the resistance response of the double haploid lines with the differential varieties to three selected Indonesian blast races and to identify the resistance genes caused the resistance to blast based on the resistance response and the genotype evaluation using molecular markers. Forty-nine double haploid lines from a double crossing IR54/Parekaligolara//Bio110/Markuti were selected using molecular markers based on the targeted genes Pib, Pi1, Pi2, Pi9, Pi33, Pir4, and Pir7. To compare the phenotype selection, ten LTH monogenic lines of differential varieties were used. All plants tested were inoculated by three selected Indonesian blast races. The results show that the Pib gene caused a resistance to race 123, while the Pi1 and Pir7 genes caused a resistance to race 123 and 133. The Pi2, Pi9, Pi33, and Pir4 genes did not cause a resistance to race 123, 133, or 173
The Use of Lactic Acid Bacteria and Cellulolytic Bacteria to Improve the Chemical Properties of Corn Flour
No full textAbstract Corn has the potential to be converted into flour, but its hard endosperm causies it to have a coarse particle size, and consequently, corn flour has high crude fiber, low protein, and high moisture. To overcome these problems, the milling of corn grain can be done by steeping it in water. The steeping process causes spontaneous growth of microbes, such as lactid acid bacteria and cellulolytic bacteria. The use of lactid acid bacteria and cellulolytic bacteria in the steeping process can soften the horny endosperm, which can enable corn grits to be ground into fine flours and which can improve the chemical properties of flour passed through an 80mesh sieve. This study aimed to obtain isolates of indigenous lactid acid bacteria and cellulolytic bacteria from the corn steeping process, and to apply them as a starter in the steeping process of corn grits to improve the fine flour yield, and the chemical properties of flour passed through an 80-mesh sieve. Isolate E2213BAL was the lactid acid bacteria selected as the highest optical density at the logarithmic phase, while isolate B2121SLT was the cellulolytic bacteria with the highest enzyme activity (4.67 mU/ml). The results showed that the use of bacteria starter and fermentation time can decrease pH, increase total acid in the fermentation liquid, decrease the crude fiber, maintain protein, and decrease the moisture of corn flour passed through an 80-mesh sieve. Abstrak Penggunaan Bakteri Asam Laktat dan Bakteri Selulolitik untuk Memperbaiki Sifat Kimia Tepung Jagung. Jagung merupakan salah satu tanaman pangan yang memiliki potensi untuk dikembangkan sebagai salah satu produk bahan pangan berupa tepung. Proses pengolahan jagung menjadi tepung memiliki kendala karena biji jagung memiliki bagian endosperm yang keras (horny endosperm), sehingga tepung yang dihasilkan memiliki ukuran partikel yang besar, selain itu tepung jagung yang beredar masih memiliki kadar serat yang rendah, kadar protein yang rendah, dan kadar air yang tinggi. Untuk mengatasi permasalahan tersebut, maka pada proses pengolahan jagung menjadi tepung, perlu adanya tahap perendaman. Perendaman menyebabkan pertumbuhan mikrob secara spontan, diantaranya adalah bakteri asam laktat dan selulolitik. Bakteri asam laktat bersama bakteri selulolitik mampu melunakkan bagian biji jagung sehingga memudahkan pada saat penggilingan menjadi tepung. Penelitian bertujuan memperoleh isolat bakteri asam laktat dan bakteri selulolitik dari proses perendaman grits jagung secara spontan, dan menggunakannya sebagai starter pada proses perendaman grits jagung untuk meningkatkan rendemen tepung, dan memperbaiki sifat kimia tepung lolos 80 mesh. Bakteri asam laktat terpilih adalah isolat E2213BAL yang memiliki optical density terbesar pada fase logaritmik sedangkan bakteri selulolitik terpilih adalah isolat B2121SLT yang memiliki aktivitas enzim dan aktivitas spesifik enzim selulase tertinggi. Hasil penelitian menunjukkan bahwa penggunaan bakteri starter dan waktu fermentasi dapat menurunkan pH, meningkatkan total asam pada cairan fermentasi, menurunkan kadar serat kasar, mempertahankan kadar protein, dan menurunkan kadar air tepung jagung lolos 80 mesh. Keywords: cellulolytic bacteria, corn flour, lactid acid bacteria, steepin
Solution of Dirac Equations for Cotangent Potential with Coulomb-type Tensor Interaction for Spin and Pseudospin Symmetries Using Romanovski Polynomials
No full textAbstract The bound state solutions of Dirac equations for cotangent function potential with the Coulomb-type tensor potential under spin and pseudospin symmetric limits are obtained using finite Romanovski polynomials. The approximate relativistic energy spectra are obtained for spin and pseudospin symmetries exactly. The radial wave functions are obtained in terms of Romanovski polynomials in the limit of spin and pseudospin symmetric conditions. The Coulomb type tensor potential removes the doublet degeneracies for pseudospin and spin symmetric cases. The relativistic energy spectrum for the exact spin symmetric case reduces to the non-relativistic energy spectrum in the non-relativistic limit. Abstrak Solusi Persamaan Dirac untuk Potensial Kotangen dengan Tensor Interaksi Tipe-Coulomb untuk Simetri Spin dan Pseudospin Menggunakan Polinomial Romanovski. Solusi keadaan terikat dari persamaan Dirac untuk potensial fungsi kotangen dengan potensial tensor tipe-Coulomb untuk simetri spin dan pseudospin diperoleh menggunakan polinomial Romanovski terbatas. Aproksimasi spektrum energi relativistik diperoleh secara eksak untuk simetri spin dan pseudospin. Fungsi gelombang radial diperoleh dalam bentuk polinomial Romanovski untuk keadaan simetri spin dan pseudospin. Potensial tensor tipe-Coulomb menghilangkan degenerasi doublet untuk kedua kasus simetri spin dan pseudospin. Pada batas non-relativistik, spektrum energi relativistik untuk kasus simetri spin eksak tereduksi menjadi spektrum energi non-relativistik. Keywords: cotangent potential, Coulomb-type tensor, Dirac equation, pseudospin symmetry, Romanovski polynomial