Biosynthesis of gold nanoparticles-peanut shell composite for catalytic reduction of methyl blue

Gold nanoparticles (AuNPs) have been recognized as an active and effective catalyst for many organic transformations. Currently, there is a growing need to develop AuNPs synthesis process that avoids the use of toxic chemicals or high energy requirements. In this research, the aqueous Phaleria macrocarpa (Mahkota dewa) dried fruit extract was used in the biosynthesis of AuNPs immobilized on peanut shell powder. The peanut shell supported AuNPs were characterized by UV-visible spectroscopy (UV-Vis), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis (TGA), Nitrogen (N2) adsorption-desorption and atomic absorption spectroscopy (AAS) techniques. The biosynthesized AuNPs were characterized by the appearance of a surface plasmon resonance (SPR) band at 534 nm in the UV-Vis spectrum. The XRD, TEM and TGA analytical data of AuNPs/Peanut shell composite indicated that the AuNPs with face-centered cubic (fcc) crystalline shape, mostly spherical and average particle size of 20.00 ± 4.19 nm were well dispersed on the peanut shell powder support. The FTIR analysis suggested that the C=O and OnH groups in the peanut shell powder have a strong affinity to bind and stabilize the AuNPs. The BET surface area of the AuNPs/Peanut shell composite catalyst determined is 35.39 m2 g-1 while the BJH pore volume is 0.035 cm3 g-1 with a pore diameter of 2.07 nm. AAS elemental analytical data showed the Au loading is 0.03 mmol per gram of catalyst. The catalytic performance of the AuNPs/Peanut shell composite was investigated for the reduction of aqueous methyl blue (MB) at room temperature. The reduction of MB obeyed a pseudo-first-order reaction with the highest rate constant of 0.124 min-1. The supported AuNPs/Peanut shell composite catalyst could be easily recovered and reused for at least three times without significant loss of activity

Effect of flow resistance in open rectangular channel

The determination of flow resistance for open channels remains a challenge in practices. In this research, an experimental study was carried out to investigate the hydraulic roughness characteristics in an open channel. The experimental flume (10 m length, 0.30 m width and 0.46 height) was carried out with two conditions ; contain gravel bed and without gravel bed (as controller). Blocks of concrete foam were fabricated and laid on the bed surface for providing uniformly roughened along the open channel. A velocity flow meter was used to quantify the average velocity, and other parameters such as cross-section, hydraulic radius, wetted perimeter, and channel slopes were also calculated. Finally, the flow resistance, n obtained using the flume with gravel bed surface is higher than the flume without gravel bed surface. The flow conditions were declared as subcritical as the Froude number is less than 1 for both conditions in the flume. As a conclusion, it was identified that the hydraulic roughness n, was influenced by the type bed roughness, flow rate and channel slope

Kolaboratif guru sebagai mediator kepada kepimpinan strategik dan kualiti pengajaran guru

Strategic leadership is one of the leadership practices inherent in the education world and is believed to influence the teaching quality. The 2013-2025 PPPM report shows that teacher collaboration is one of the elements that can improve teaching quality. Previous studies have shown different findings on strategic leadership practices, teacher collaboration and teaching quality and many other studies have focused on specific aspects of the implementation process but have not studied the process thoroughly. This study aims to identify the collaborative role of teachers in relation to strategic leadership and teaching quality. In particular, researchers have examined the levels of strategic leadership, teacher collaboration and the teaching quality. The relationships among the variables are also investigated. This quantitative study involved 300 teachers, identified by stratified random sampling, representing the 2 types of maahad school, Maahad Kawalan dan Maahad Pilihan, in the state of Kelantan. Data were collected from distributed questionnaires and systematically analysed utilizing descriptive and inferential analysis with the aim of improving the validity of findings and interpretation. The findings show that there are differences between the levels of teacher collaborative practice in both categories; whereas the findings for the strategic leadership level and the teaching quality indicate that there is no difference between the two categories. Further findings show that there is a relationship between strategic leadership and teaching quality; strategic leadership and teacher collaboration; teacher collaboration and teaching quality. The findings also show that teacher collaboration is a partial mediator in the relationship between strategic leadership and teaching quality. Based on the findings, it is proposed that school leaders should continue to strengthen collaborative practices among teachers as an effort to improve teaching quality in their respective schools which will, in turn help to improve school excellence, especially across the current era of globalization

Evaluation of anti-gout potential of selected Malaysian medicinal plants

Gout is a type of arthritis that causes painful inflammation in joints due to the elevation of uric acid in the blood. Allopurinol is a common drug used for treating gout. However, due to unwanted side effects, new alternatives with fewer side effects are desired. The objectives of the study are to screen the six potential Malaysian medicinal plants for anti-gout activity using in vitro enzyme assay; to optimize the extraction conditions of the three selected plants using response surface methodology (RSM); to determine the cell viability of the three extracts towards RAW 264.7 murine macrophage cell line; to investigate the in vivo anti-gout mechanism of three selected plants; and to profile the bioactive compounds present in the three selected plant extracts. Six selected plants were screened for their anti-gout activity in vitro of which three plants (i.e Euphorbia hirta, Strobilanthes crispa and Christia vespertilionis) were further analyzed for their optimum extraction conditions using RSM. The effects of the plant extracts on the serum uric acid levels in hyperuricemic rats were then evaluated and lastly the bioactive compounds of the plant extracts were analyzed using liquid chromatography-mass spectrometry (LC-MS). E. hirta, S. crispa and C. vespertilionis exhibited XO inhibitory activity in vitro with more than 60 % at 100 µg/mL. Findings showed that the optimum extraction conditions of phytochemical compounds and anti-gout activity of these plants were at temperature of 65.09-79.07 °C for 5.0-17.42 min with solid to liquid ratio of 1:17.33-1:20 g/mL, respectively. C. vespertilionis displayed less cytotoxic against RAW264.7 cells as compared to S. crispa and E. hirta. For the in vivo study, the treatment of the hyperuricemic rats with 200 mg/kg of E. hirta, S. crispa and C. vespertilionis extracts reduced the serum uric acid levels significantly by more than 40 % as compared to hyperuricemic rats. The LC-MS analysis also revealed the presence of phytochemicals such as flavonoid and phenolic compounds in the plant extracts which might be associated with the anti-gout activity. Hence, this study clearly demonstrated that E. hirta, S. crispa and C. vespertilionis aqueous extracts are potential as anti-gout agents

The impact of genetics, environmental, and geographical factors on inter-individual and inter-ethnic differences in CYP2C9-catalysed drug metabolism

Inter-individual and inter-ethnic variations in drug metabolism are creating an obstacle in providing efficient and effective drug treatments especially for drugs with narrow therapeutic windows. This thesis is contributes to the understanding of the molecular mechanism of these variations. Paper I is an introduction to the inter-individual and inter-ethnic differences in CYP2C9 catalysed drug metabolism. Wide inter-individual differences were observed in the metabolic ratio of losartan to E-3174 metabolite even among individuals who were not carrying defective alleles CYP2C9*2 and CYP2C9*3. Inter-ethnic variation was observed in the metabolism of losartan between CYP2C9 wild type Koreans and Swedes. An allelic variation in the intronic region between exon 8 and 9 of CYP2C9, IVS8-109A>T was observed to cause a lower CYP2C9 activity in Swedes but not Koreans. Paper II studied the combination of age, CYP2C9 genotype, ethnicity, smoking habit, weight and sex as a predictor of CYP2C9 metabolic ratio variability. Ethnicity was the main significant factor influencing between subject-variability in CYP2C9 enzyme activity. Additionally, CYP2C9 genotype and smoking were significant contributors to the variation. Grouping the subjects based on their ethnicity, we found that CYP2C9 genotype is a major predictor for both Koreans and Swedes (27% and 40% of the variability respectively). The smoking effect was non-significant in the Swedes but remains as a factor in the Koreans. The reason behind the smoking effect in Koreans is unidentified. Paper III investigated the possibility of Behcet’s disease as a CYP2C9 inducer. A Swedish ultra-rapid CYP2C9 metaboliser was diagnosed with this disease and this study tested the possibility in Turkish healthy subjects to have a lower CYP2C9 activity than Behcet’s disease patients. Interestingly, the Behcet’s disease patients were shown to have a significantly low CYP2C9 metabolic activity. The factors of genetics, medication and inflammation-related biomolecules are suspected to have caused this down-regulation. We did not find evidence of CYP2C9 genotype and typical Behcet’s disease medication, colchicine having any influence on the observed low CYP2C9 metabolic activity. It is very possible that inflammation response agent caused this inhibitory effect on CYP2C9 activity. Paper IV investigated the effect of the P450 oxidoreductase (POR)*28 variant on the metabolic activity of CYP2C9. We screened all Swedish and Koreans CYP2C9*1/*1 subjects for POR* 5, *13 and *28. No subject was found to carry *5 or *13. Interestingly, Swedish individuals who carry POR*28 allele were observed to display a 1.40 fold increase in CYP2C9 enzyme activity compared to none-POR*28 carriers. We screened the ultra-rapid metaboliser for this variant and she was also a carrier of this variant. More studies should be done to investigate the effect of other SNPs in POR gene to the metabolic activity of drug metabolising enzymes

Secondary metabolites, antioxidant, and antiproliferative activities of Dioscorea bulbifera Leaf Collected from Endau Rompin, Johor, Malaysia

Breast cancer is among the most commonly diagnosed cancer and the leading cause of cancer-related death among women globally. Malaysia is a country that is rich in medicinal plant species. Hence, this research aims to explore the secondary metabolites, antioxidant, and antiproliferative activities of Dioscorea bulbifera leaf collected from Endau Rompin, Johor, Malaysia. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assays, while the cytotoxicity of D. bulbifera on MDA-MB-231 and MCF-7 breast cancer cell lines was tested using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cell cycle analysis and apoptosis were assessed using flow cytometry analysis. Phytochemical profiling was conducted using gas chromatography-mass spectrometry (GC-MS). Results showed that methanol extract had the highest antioxidant activity in DPPH, FRAP, and ABTS assays, followed by ethyl acetate and hexane extracts. D. bulbifera tested against MDA-MB-231 and MCF-7 cell lines showed a pronounced cytotoxic effect with IC50 values of 8.96 μg/mL, 6.88 μg/mL, and 3.27 μg/mL in MCF-7 and 14.29 μg/mL, 11.86 μg/mL, and 7.23 μg/mL in MDA-MB-231, respectively. Cell cycle analysis also indicated that D. bulbifera prompted apoptosis at various stages, and a significant decrease in viable cells was detected within 24 h and substantially improved after 48 h and 72 h of treatment. Phytochemical profiling of methanol extract revealed the presence of 39 metabolites such as acetic acid, n-hexadecanoic acid, acetin, hexadecanoate, 7-tetradecenal, phytol, octadecanoic acid, cholesterol, palmitic acid, and linolenate. Hence, these findings concluded that D. bulbifera extract has promising anticancer and natural antioxidant agents. However, further study is needed to isolate the bioactive compounds and validate the effectiveness of this extract in the In in vivo model

A proposed framework for FTMSK alumni / Fazleen Noorhuda Abdul Majid

Providing a good online service requires access to lots of data. At most organizations, this data is spread among different data store and in different data formats. To solve the problem, a repository can be used as a data layer in order to define a generic representation of a data store. Basically, the purpose of this research is to investigate the concept of repository and propose FTMSK Alumni information repository framework. The framework can be used as a guideline to develop FTMSK Alumni website, which share a common business model and required database, electronic document and workflow, and internet functionality. The framework is based on information repository which store accesses and manages information sources and/or information processes. Repository item are used to access data by identifying the detailed object of each items. Consequently, all the related information can be captured by the repository and most importantly, accessing data has to be eas