Masalah Pelajar dalam Menamakan Sebatian-Sebatian Organik Berpolifungsi

An investigation of students' unsuccessful attempts in naming poly functional organic compounds using the IUPAC nomenclature is described, The effectiveness of the teaching strategies used to help students develop skill and confidence in using the systematic nomenclature is also discussed

A Systematic Approach to Solving Problems in Structure Analysis

An investigation of students' unsuccessful attempts to solve problems in structure analysis, even though they possessed all the prerequisite knowledge, is described. The proposed teaching strategies given to these students to help them develop confidence and skills in problem-solving and the evaluation of these strategies are discussed

16S rRNA Barcoding technique for species identification of processed sea cucumbers from selected Malaysian markets

In food industry, wide-ranging processing of sea cucumbers (Phylum Echinodermata: Class Holothuroidea) including gutting, boiling, roasting, and subsequent preservation procedures are frequently needed prior to marketing. These processes cause body deformation of the sea cucumbers, thus leading to difficulties in species identification and confirmation of the processed sea cucumbers or beche-de-mer. Furthermore, beche-de-mer products in Malaysian markets are often unlabelled or mislabelled. Economic fraud, health hazards, and illegal trade of protected species are the potential major consequences of the issues. Therefore, a reliable, reproducible, and rapid technique for species identification is required. For that reason, this study was conducted to determine species identity of 25 beche-de-mer specimens that were not tagged with species details from four selected Malaysian markets. Five reference samples were also included in the analyses consisting of fresh samples that were morphologically identified as Stichopus horrens and Holothuria (Mertensiothuria) leucospilota from Pangkor Island, Perak, Malaysia. Phylogenetic analyses of 30 partial sequences of non-protein-coding 16S mitochondrial ribosomal RNA (rRNA) gene using five main methods i.e. Neighbour-Joining (NJ), Maximum Likelihood (ML), Minimum Evolution (ME), Unweighted Pair Group Method with Arithmetic Mean (UPGMA), and Maximum Parsimony (MP) showed the presence of two main clusters of the beche-demer specimens: Stichopodidae (gamat family) and Holothuriidae (timun laut family). The beche-de-mer specimens of S. horrens, Stichopus herrmanni, and Thelenota anax were the three gamat species that clustered under the family Stichopodidae. Meanwhile, the beche-de-mer specimens of H. leucospilota, Holothuria (Halodeima) edulis, Holothuria (Metriatyla) scabra, and H. scabra var. versicolor were the four timun laut species that clustered under the family Holothuriidae. In fact, the outcomes of this study suggested the potential of 16S mitochondrial rRNA gene sequencing technique to be used by the enforcement agencies in monitoring and overcoming the issues of species substitution and product mislabeling of beche-de-mer products in Malaysian markets

Identification of bacteria associated with Holothuria (Mertensiothuria) leucospilota from Pangkor Island

Holothuria (Mertensiothuria) leucospilota is the most abundant sea cucumber species in Malaysia. This study aimed to identify bacteria isolated from the external and internal body parts of H. leucospilota collected from the coastal water of Pangkor Island, Perak, Malaysia. A total of 26 bacterial samples were isolated using streak plate method from eight body parts of two fresh H. leucospilota specimens and from the surrounding surface sediments and seawater. Identification of the bacterial isolates was based on microscopic examination, 16S rDNA amplification and phylogenetic analysis using the neighbour-joining method. Three genera of bacteria were identified namely Vibrio, Bacillus, and Acinetobacter. The genus Vibrio was found to be the main bacterial group associated with the H. leucospilota specimens from Pangkor Island

Phylogeny of holothuria leucospilota (echinodermata: holothuroidea) as inferred from cytochrome c oxidase i mtDNA gene sequences

This study aimed to generate the genetic profile of Holothuria (Mertensiothuria) leucospilota (Brandt 1835) from Intan Besar Island, Langkawi, Kedah Darul Aman, Malaysia and then to determine the phylogenetic relationship between H. leucospilota and other members of genus Holothuria available in the GenBank using partial sequences of cytochrome c oxidase I (COI) mitochondrial DNA (mtDNA) gene. In this study, tree topologies of neighbour joining, maximum parsimony and maximum likelihood show that H. leucospilota has its own monophyletic clade clearly distinct from the other species and it is genetically closer to Holothuria (Acanthotrapeza) coluber Semper 1868

Isolation and identification of amylolytic bacteria from ragi

Ragi is a traditional dry starter culture frequently used in many fermented food products in Asian countries. Ragi contains starch that can be degraded by amylases provided by bacteria and other microorganisms during fermentation in producing fermented foods. This study was carried out to isolate bacteria from ragi and to screen for their ability to hydrolyse starch. Seven bacterial colonies were isolated from ragi, with three samples showing starch hydrolysis activity. Two of the starchdegrading bacterial isolates were identified using partial 16S rRNA gene sequencing as Bacillus licheniformis with 97% and 98% similarity, and one sample identified as a lactic acid bacteria, Enterococcus faecium (98%). Isolation and identification of these bacteria from ragi can provide a promising source of amylase that can be further studied and manipulated for the development of starter culture and to improve the quality of traditional ragi-based fermented food products

RFID data reliability optimiser based on two dimensions bloom filter

Radio frequency identification (RFID) is a flexible deployment technology that has been adopted in many applications especially in supply chain management. RFID system used radio waves to perform wireless interaction to detect and read data from the tagged object. However, RFID data streams contain a lot of false positive and duplicate readings. Both types of readings need to be removes to ensure reliability of information produced from the data streams. In this paper, a single approach, which based on Bloom filter was proposed to remove both dirty data from the RFID data streams. The noise and duplicate data filtering algorithm was constructed based on bloom filter. There are two bloom filters in one algorithm where each filter holds function either to remove noise data and to recognize data as correct reading from duplicate data reading. Experimental results show that our proposed approach outperformed other existing approaches in terms of data reliability

Biosynthesis of Diverse Class Flavonoids <em>via</em> Shikimate and Phenylpropanoid Pathway

Flavonoids are natural products, which are useful in the protection of various types of human diseases. Several bioactive flavonoids as chalcones, flavonols, flavanol, flavones, flavanone, flavan, isoflavonoids, and proanthocyanidin, are found in parts as leaves, root, bark, stem, flowers, weed, fruits of plant species. Flavonoids are synthesized in higher plant species via the shikimate pathway, phenylpropanoid and polyketide pathway. The chalcones and flavanones are central intermediates of the pathway, which give several diverse classes of flavonoids. Central intermediates pathway (chalcones and flavanones pathway) depends on plants species and group of enzymes such as hydroxylases, reductases and isomerases to give different classes of flavonoids skeleton. The anthocyanins, isoflavonoids and condensed tannin (proanthocyanidins) are an important class of flavonoids, which synthesized by flavanones. Mostly, biosynthesis of flavonoids start from phenylpropanoid pathway. The phenylpropanoid pathway starts from shikimate pathway. The shikimate pathway starts from phosphoenol pyruvate and erythrose 4-phosphate

Protein produced by Bacillus subtilis ATCC21332 in the presence of Cymbopogon flexuosus essential oil

Proteins levels produced by bacteria may be increased in stressful surroundings, such as in the presence of antibiotics. It appears that many antimicrobial agents or antibiotics, when used at low concentrations, have in common the ability to activate or repress gene transcription, which is distinct from their inhibitory effect. There have been comparatively few studies on the potential of antibiotics or natural compounds in nature as a specific chemical signal that can trigger a variety of biological functions. Therefore, this study was focusing on the effect of essential oil from Cymbopogon flexuosus in regulating proteins production by Bacillus subtilis ATCC21332. The Minimum Inhibition Concentration (MIC) of the C. flexuosus essential oil on B. subtilis was determined by using microdilution assay, resulting 1.76mg/ml. The bacteria cells were further exposed to the C. flexuosus essential oil at concentration of 0.01 MIC for 72 h. The proteins were then isolated and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Proteins profile showed that a band with approximate size of 30 kDa was appeared for the treated bacteria with C. flexuosus essential oil. Thus, B. subtilis ATCC21332 in stressful condition with the presence of C. flexuosus essential oils at low concentration could induce the protein production. The isolated protein also showed antimicrobial activity against selected Gram-positive and Gram-negative bacteria