Determination of effective diffusion coefficient of immobilized Baker's yeast invertase in various concentration of PVA-alginate matrix

Baker's yeast invertase is immobilized in PVA-alginate matrix using an improved method. PVA beads were prepared by adding calcium alginate to improve its stability, mechanical and chemical properties. Boric acid was used as the cross-linking agent and additional chemicals consisting of 10% boric acid and sodium sulphate solution was used as a treatment solution to harden the PVA-alginate beads. The determination of the effective diffusion of PVA-alginate matrix the vital step in optimizing the preparation of immobilized and water-soluble biocatalyst. In this study the two-level full factorial design was used to investigate the effect of PVA and boric acid concentrations and diffusions coefficient. Diffusion coefficient (De) is one of the factors that significantly affect the mass transport within the immobilization matrix. De value varies for each concentration of PVA and boric acid. The result concluded that both factors significantly affect the De. A maximum De value of 5.0141 x 10(-5) cm2s-1 was obtained at boric acid and PVA concentraion of 7w/v and 10.5 w/v respectively

Pengaruh Pemberian Dosis Mineral Ca dan Lama Fermentasi Pelepah Sawit terhadap Kandungan Lignin, Kecernaan BK, BO, PK dan Fraksi Serat (NDF, ADF, Hemiselulosa dan Selulosa) Menggunakan Kapang Phanerochaete Chrysosporium

Pelepah sawit dapat dimanfaatkan sebagai pakan ternak tetapi terkendala karena tingginya kandungan lignin. Strategi yang dapat dilakukan untuk menurunkan kandungan lignin pelepah sawit adalah melalui fermentasi menggunakan kapang Phanerochaete chrysosporium (Pc). Pertumbuhan kapang Phanerochaete chrysosporium dipengaruhi oleh ketersediaan mineral dalam substrat. Untuk itu diperlukan penambahan mineral sesuai dengan kebutuhan kapang dimana salah satunya adalah mineral kalsium (Ca). Penelitian ini bertujuan untuk melihat pengaruh pemberian dosis mineral Ca dan lama fermentasi dalam menurunkan kandungan lignin, meningkatkan kecernaan BK, BO, PK, NDF, ADF, Selulosa dan Hemiselulosa pelepah sawit yang difermentasi menggunakan kapang Phanerochaete chrysosporium. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) pola faktorial untuk menghitung persentase penurunan lignin dan Rancangan Acak Kelompok (RAK) pola faktorial dengan tiga kali ulangan. Faktor A yaitu pemberian dosis mineral Ca yaitu A0: kontrol (pelepah + Pc) + 0 ppm Ca, A1: kontrol + 1000 ppm Ca, A2 : kontrol + 1500 ppm Ca, A3 : kontrol + 2000 ppm Ca. Faktor B adalah lama waktu fermentasi yaitu Y1: 10 hari, Y2 : 15 hari dan Y3 : 20 hari. Data dianalisis menggunakan analisa varian (Anova) dan untuk melihat perbedaan antar perlakuan dilakukan uji lanjut Duncan\u27s Multiple Range Test (DMRT) (Steel and Torrie, 1991). Hasil sidik ragam menunjukkan perlakuan memberikan pengaruh berbeda nyata (P<00.1) terhadap penurunan kandungan lignin, kecernaan BK, BO, PK, NDF, ADF, Hemiselulosa dan Selulosa. Penelitian ini dapat disimpulkan bahwa fermentasi pelepah sawit menggunakan kapang Phanerochaete chrysosporium pada dosis mineral Ca 2000 ppm dengan lama fermentasi 10 hari dapat menurunkan kandungan lignin 26,79% dengan kecernaan BK 51,44%., BO 53,24%., PK 47,54%., NDF 47,48%., ADF 42,24%., Selulosa 45,44% dan Hemiselulosa 48,34%

A noninvasive molecular approach: exploiting species-locus-specific PCR primers in defeating numts and DNA cross-contamination of cercopithecidae

The lack of a standardized, noninvasive molecular approach to studying genetic aspects of primates has made it hard for primatologists to decode the evolutionary history of these species. Researchers must optimize their own techniques to fully exploit the available samples. Lack of species-locus-specific primers also contributes to difficulties in using noninvasive genetic samples. Thus, the objectives of this study were to develop a standardized technique to collecting samples noninvasively, propose newly designed species-locus-specific primers, and optimize conditions for polymerase chain reaction (PCR) for Macaca fascicularis, M. nemestrina, Trachypithecus cristatus, and T. obscurus. Nine new species-locus-specific primers for three different loci of mitochondrial DNA, namely D-loop, cytochrome oxidase subunit I (COI), and cytochrome b, were successfully designed. These primers proved to be efficient in amplifying larger datasets (up to ~1,000 bp) of the targeted species in the optimized PCR conditions. The species-locus-specific primers are able to anneal to host DNA alone in highly contaminated feces of highlighted species. They can also offer alternatives measures in avoiding contamination related to nuclear insertion of mitochondrial pseudogenes (numts)

Removal of bisphenol A from aqueous media using a highly selective adsorbent of hybridization cyclodextrin with magnetic molecularly imprinted polymer

In this study, a unique magnetic molecularly imprinted polymer (MMIP) adsorbent towards bisphenol A (BPA) as a template molecule was developed by bulk polymerization using β-cyclodextrin (β-CD) as a co-monomer with methacrylic acid (MAA) to form MMIP MAA–βCD as a new adsorbent. β-CD was hybridized with MAA to obtain water-compactible imprinting sites for the effective removal of BPA from aqueous samples. Benzoyl peroxide and trimethylolpropane trimethacrylate were used as the initiator and cross-linker, respectively. The adsorbents were characterized by Fourier transform infrared spectroscopy, scanning electronic microscopy, transmission electron microscopy, vibrating sample magnetometer, Brunauer–Emmett–Teller and X-ray diffraction. 1H nuclear magnetic resonance spectroscopy was used to characterize the MAA–βCD and BPA–MAA–βCD complex. Several parameters influencing the adsorption efficiency of BPA such as adsorbent dosage, pH of sample solution, contact time, initial concentrations and temperature as well as selectivity and reusability study have been evaluated. MMIP MAA–βC

Implementation of Two Way Free Space Quantum Key Distribution

We report an implementation over free space medium of a two way four states quantum key distribution (QKD) protocol namely the LM05. The fully automated setup demonstrated a secure key generation rate of 3.54 kbits per second and quantum bit error rate (QBER) of 3.34% at mean photon number ({\mu}) = 0.15. The maximum tolerable channel loss for secure key generation considering Photon Number Splitting (PNS) attack, was 5.68 [dB]. The result successfully demonstrated the feasibility of a two way QKD protocol implementation over free space medium.Comment: To appear in the April 2012 issue of Optical Engineering (Vol. 51, No. 04

Microwave assisted K2CO3 palm shell activated carbon as sorbent for CO2 adsorption application

Carbon dioxide is believed to be a major greenhouse gas (GHG) that contributes to global warming. In this study, palm shells were used as a precursor to prepare CO2 activated carbon sorbents via carbonization, chemical impregnation with K2CO3 and microwave activation. Adsorption equilibrium data for CO2 adsorption on the porous carbon were obtained at different temperatures using static volumetric adsorption method. Langmuir, Freundlich, Sips and Toths models were used to correlate the experimental data. The CO2 adsorption capacity at 303.15, 343.15, 378.15 443.15 K and 1 bar on the sorbent was 2.71, 1.5, 0.77, 0.69 mmol/g respectively. Sips isotherm was found to have the best fit. The results indicated that the porous carbon sorbent prepared by carbonization and microwave K2CO3 assisted activation have good CO2 uptake. The porous carbons produced are therefore good candidates for CO2 adsorption applications

User friendly system for the visually impaired in learning Al-Quran

This study presents a method to enable the visually impaired Muslim to learn and read the Al-Quran using Braille Display with software help. The system reads the database which contains all verses of Al-Quran and user will need to select the verse and ayah to read. Besides that, this system can be used in a class to teach visually impaired students to learn Al-Quran. Every word or character typed by the instructor in the main Braille Panel will be transmitted to the sub Braille Panel that is connected to the main Braille Panel. The selected verse of Al-Quran and ayah will also generate an index before being transmitted to the Braille Panel. The index will be transmitted to the Braille Display for people to touch and read the display. A user friendly Graphical User Interface (GUI) will be used to fulfill the ergonomics for the visually impaired user's physical capabilities. Several approaches are used to design and implement the interface for the visually impaired like speech or sound output and Braille display. The Braille codes can be displayed using the Braille panel. The design interface and structure of the system for the visually impaired users in learning Al-Quran is presented

Isolation and characterization of polyhydroxyalkanoates (PHAS) producing bacteria from brackish stream

Polyhydroxyalkanoates (PHAs) are biopolymers which have similar characteristics with petrochemical plastics but a step better due to its biodegradable property. A total of 23 strains were isolated from two different brackish sources. In order to detect the PHAs granules, the PHAs producing bacteria were first screened with Sudan Black B staining. Twenty strains were observed with lipid granules and were subjected to further confirmation with Nile blue staining. From the Nile blue staining, only 10 strains have the ability in producing PHAs and 2 were identified as strong PHAs producers. This study focuses on the 2 strains named S1 and L1. Further identification procedure was carried out and found that strain S1 and L1 belongs to Pseudomonas sp. L1 strain was found to be promising for PHAs production since it accumulated PHAs for about 88.3%. The PHAs produced by this strain was analyzed using Fourier Transform Infrared Spectroscopy (FT-IR) and Nuclear Magnetic Resonance (NMR) analysis and was identified as poly-3-hydroxybutyrate (P-3HB)

Development of hybrid coconut shell-peek adsorbent for methane adsorption: optimization using response surface methodology

Adsorbed natural gas (ANG) provides efficient and clean combustion, with minimal emissions compared to diesel and gasoline. This article was designed to develop techniques of ANG for transportation application by apply RSM and CCD to identify the optimum preparation conditions for preparation of stable adsorbent for methane adsorption. Coconut shell and poly ether ketone (PEEK) was selected for synthesis of activated carbon (AC). The effectiveness of the parameters was determined using response surface method (RSM) couple with central composite design (CCD). The analysis of variance (ANOVA) was applied to identify the significant parameters. The quadratic model was adopted, as it has the highest F-value of 21.62 and P-value of less than 0.05, which relate the parameters and response. Microwave power has the highest F-value of 62.36. The maximum methane uptake of 5.12mmol g-1 was achieved. Overall, the hybrid coconut-PEEK adsorbent was found to be suitable for CH4 adsorption