Makara Journal of Science
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Cloning of a Gene Encoding Protease from Bacillus halodurans CM1 into Escherichia coli DH5 and Expression Analyses of the Gene Product
No full text Bacillus halodurans strain CM1 is an Indonesia alkalothermophilic bacterium isolated from Cimanggu Hot Spring, Bandung, West Java. This bacterial strain produces high levels of thermoalkalophilic xylanase. It has also been predicted to produce other potential industrial enzymes, including protease. For production and application of protease in the future, the protease gene from B. halodurans CM1 was cloned into Escherichia coli. The protease gene was isolated from B. halodurans CM1 by the PCR approach using primers designed based on the GenBank. The PCR product was then ligated into pGEM-T Easy vector, transformed into E. coli DH5α, verified, and analyzed based on DNA sequencing data using the BLAST search tool. A 1086-bp protease gene was obtained that exhibited a very high sequence similarity (99%) with that of alkaline protease gene from B. halodurans C-125. When the culture of this positive recombinant E. coli DH5α containing the protease gene was spotted onto calcium caseinate agar, a clear zone appeared after incubation at 50°C. This result demonstrated that the protease gene was expressed in this recombinant E.coli DH5α.  
Single Nucleotide Polymorphism within the Promoter Region of Cynomolgus Monkey LDLR Gene
No full textThe cynomolgus monkey (Macaca fascicularis) is one of the most common nonhuman primates used as an animal model in biomedical research related to atherosclerosis. However, little is known about genetic variation in the low density lipoprotein receptor (LDLR) gene, its effect on cholesterol levels, and associated risks of atherosclerosis. Therefore this study aimed to identify genetic polymorphisms, namely single nucleotide polymorphisms (SNPs), within the promoter region of LDLR and their relationship with animal responsiveness to hypercholesterolemia due to an atherogenic diet. In this research, SNPs were studied using DNA isolated from 22 cynomolgus monkeys obtained from a previous study, consisting of two hyporesponders, 19 hyperresponders, and one extreme case. The result showed that two SNPs existed in the promoter region, namely g.−169T>C and g.−265G>A. SNP g.−265G>A showed linkages with extreme responsiveness and can be used as a potential genetic marker for extreme animals. The result of this study has extended our knowledge of polymorphism in the LDLR gene and its use in the selection of cynomolgus monkeys as animal models in research on hypercholesterolemia and atherosclerosis
Proximate Composition, Total Phenolic Content, and Sensory Analysis of Rice Bran Tempeh
No full textTempeh is a fermented food prepared using the raw materials of soybean fermented by Rhizopus sp. This traditional food is fairly highly consumed in Indonesia. Soybean, which is the primary raw material used in the processing of tempeh, is still being imported due to its insufficient production in Indonesia. Rice bran can be used as a substitute for soybeans in tempeh processing to add to its (health) benefit. Rice bran has good nutritional value as it contains a high total content of phenolic compounds, dietary fiber, fat, and the amino acid lysine. Thus, rice bran provides an opportunity to use it as a product with functional properties. This study was conducted to determine the proximate characteristics, the total phenolic content (TPC), and the sensory properties of tempeh with the addition of rice bran, chitosan, and glucono delta-lactone (GDL). The addition of chitosan was used as a source of prebiotic, and GDL was required to accelerate the fermentation process. The chemical characteristics (protein, fat, and water content), the TPC, and the sensory properties (color, aroma, texture, and overall acceptability) of rice bran tempeh were analyzed. Results showed that the tempeh sample with the addition of 20% (w/w) rice bran showed the best sensory analysis. It consisted of 57.23% of water content, 37.42% of protein content, 19.72% of fat content, and 83.98 mg GAE/100 g of TPC
The Influence of Nutrient (N and P) Enrichment and Ratios on Phytoplankton Abundance in Keunekai Waters, Weh Island, Indonesia
No full textThe Keunekai waters around Weh Island, Indonesia, have become a prone coastal area because of degradation from climate anomalies and anthropogenic pressure. The high level of coral mortality caused by mass bleaching and fish bombing several years ago may have led to the deterioration of the water conditions and the disruption of the biogeochemical cycle, resulting in potential nutrient enrichment and algae blooms (eutrophication). This study aimed to determine the influence of nutrient ratios on phytoplankton abundance and monitor the existing water conditions around Keunekai. Spectrophotometry analysis was used to determine the concentrations of the nutrients, and the Sedgewick-Rafter counting method was used to identify the species and abundance of the phytoplankton. A large variation in N content (ranging from 1.1 to 1.6 mg N/L) and, particularly, P content (ranging from 0.02 to 0.18 mg P/L) most likely reflected differences in the supply ratios of N and P, rather than differences in absolute N and P availability. Three taxa of phytoplankton and their relative abundance were identified in the study area: Bacillariophyceae (diatom) (72%), Cyanophyceae (3%), and Dinoflagellate (25%). It was found that P-limitation mostly controls potential algae blooms, which support the density of Dinoflagellates that may endanger the water
Morphological Characterization of Okra (Abelmoschus [Medik.]) Accessions
No full textOkra (Abelmoschus [Medik.] species) is a prominent vegetable due to the diverse economic roles of its leaves, fruits, seeds, floral parts, and stems. This study investigated the morphological distinctiveness among varieties and between species of okra. Five okra accessions were obtained from the National Centre for Genetic Resources and Biotechnology, Nigeria, including two A. esculentus (NG/OA/03/12/157 and NG/OA/05/12/159) and three A. caillei (NG/OA/03/12/158, NG/SA/DEC/07/0475, and NG/SA/DEC/07/0482) species. During the developmental stage, the accessions exhibited a degree of similarity; however, at maturity, the leaf and fruit color, height, leaf shape, and flowers of the five accessions became distinct. A cluster of the phenotype was observed at 4.123 level of coefficient of similarity with two distinct clusters. Distinct morphological features included the nature of the epicalyx segment, the position of the fruit on the stem, fruit shape, and fruit color. These features may be used to identify the accessions. The common morphological features of clusters 1 and 3 were leaf shape and fruit length at maturity. Significant differences were observed among all the five accessions in terms of stem length, petiole length, and leaf node. This study suggests that morphological variations exist among the accessions, which can be further enumerated through molecular characterization. The characteristics could distinguish the Abelmoschus accessions into A. caillei and A. esculentus and provide credence to the use of morphological characteristics to characterize plant genetic resources. These characteristics may be exploited by plant breeders for sustainable utilization of the okra germplasm
Micromagnetic Study on the Magnetization Reversal of Barium Hexaferrite (BaFe12O19) Thin Film
No full textThis study investigates a magnetization reversal mechanism based on the hysteresis curve of Barium Hexaferrite (BFO) thin film by micromagnetic simulation through parallel and perpendicular magnetization directions along the axes. The hexagonal shape of the BFO film was modeled with thicknesses of 5, 10, and 15 nm and a diameter size ranging from 50 to 100 nm. It was found that the coercivity field HC and the saturation field HS of the BFO film decreased as the diameter size increased and thickness decreased. It was observed that the nucleation field HN increased as the diameter size increased. An analysis of energies showed that the demagnetization energy was dominantly influenced by the diameter and thickness in comparison to the anisotropic energy. From the hysteresis curve, the switching time was also investigated. Interestingly, the switching time was faster for the thinner BFOs with a diameter under 70 nm. For particles larger than 70 nm in diameter, the switching time showed fluctuation irrespective of the BFO thickness. Based on these results, a diameter size of 70 nm is proposed as the critical size for producing the equal time for switching domain polarity.  
A Known Naphthalene, Isoeleutherol, from the Herb of Lygodium microphyllum
No full textA known naphthalene, isoeleutherol (1), was isolated from the herb of Lygodium microphyllum. The chemical structure of 1 was determined on the basis of spectroscopic data mainly UV, IR, HRTOFMS, 1D- and 2D-NMR spectroscopy, as well as by comparing with compounds previously reported. Isoeleutherol was isolated from this plant for the first time and showed moderate antioxidant activity against DPPH (2,2-diphenyl-1-picrylhydrazyl) with IC50 value of 53.96 ± 2.87 µg/mL
Craniofacial Shape of Arfak People Based on Geometric Morphometric Features
No full text Face and cranial (craniofacial) shape is highly specific to the individual; therefore, craniofacial shape is often used to identify individuals and to analyze variability in the human population. Previous studies, consisting only of verbal descriptions, suggested that the cranial shape of the Papuan people was highly variable. Despite their usefulness, verbal descriptions cannot fully demonstrate common and local variation in cranial shape. They also cannot be used to extract the general trend of variation or to group face shapes based on their similarity. Here we attempt to apply geometric analysis, a method of shape analysis, to measure facial anatomical structural landmarks of Papuan people. The craniofacial shape of Papuan people was constructed from those of Arfak people based on 16 anatomic landmarks on the lateral side. Arfak is one of the traditional Papuan tribes in Manokwari, West Papua Province. Our result showed great variation in craniofacial shapes among the Arfak. The nose, chin, and mandible differed significantly, whereas other parts of the face were relatively stable and showed small variations. These differences reflected variations in the facial growth rate. The high level of diversity thus indicates that some parts of the face have higher plasticity in their growth pattern than others. 
Molecular Dynamics Simulations of Iron-Joining Using Copper as a Filler Metal
No full textThe study of the liquid filler metal infiltration on the narrow channel of adjoining metal bears importance in understanding the mechanism of the metal brazing process. In this study, we employed the molecular dynamics simulation to understand the mechanism of Cu liquid infiltration through the narrow channel of Fe slabs. Our simulation showed that the wetting process of Fe surfaces by Cu liquid precedes the infiltration process. This study also revealed that the channel became narrower and blockages were found in the channel due to the deformation of Fe surface. In addition to the effect of viscous drag, this process should also contribute to the decreasing speed of the Cu liquid front
Optimization of Laccase Adsorption-Desorption Behaviors on Multi-Walled Carbon Nanotubes for Enzymatic Biocathodes
No full textLaccase adsorption-desorption behaviors on the surface of multi-walled carbon nanotubes (MWCNTs) were investigated using spectrophotometry and voltammetry. The optimum condition for laccase adsorption is 5.0 mg/mL of laccase in 0.01 M phosphate-buffered saline (PBS) at pH 5.0. Laccase adsorption is a reversible phenomenon that is dependent upon the nature of MWCNTs and the concentration of ionic strength in the laccase solution. Chitosan was functionalized as a nanoporous reservoir to minimize laccase desorption. Chitosan was found to protect approximately 97.2% of the adsorbed laccase from MWCNTs during the first six hours of observation. The three-dimensional (3D) biocathode, MWCNTs-laccase-chitosan with a 0.2 cm2 geometric area, was shown to have a stable open circuit potential (OCP) of 0.55 V, a current density of 0.33 mA cm-2 at 0.2 V vs. saturated calomel electrode (SCE), and a stable current for 20 hours of successive measurements. This report provides a new insight into the study of a high-performance laccase-based biocathode via optimization of adsorption and minimization of desorption phenomena