Pusat Pengajian Teknologi Industri - Tesis

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Utilisation Of Superheated Steam And Torrefacto Roasting On Quality Attributes Of Black Seed (Nigella Sativa) For Beverage Application
(2024-09)
Veeriah, Harivaindaran K.
Nigella sativa, known as black seed, has many health benefits and is typically roasted prior to consumption. This causes detrimental quality loss, thus, an innovative method such as superheated steam (SHS) and torrefacto roasting may be advantageous. This research aims to develop a beverage from SHS torrefacto (TR) roasted black seeds. In the first phase, SHS was applied to black seeds at 150℃, 200℃ and 250℃ for 10, 15, and 20 mins at each temperature then compared to convection roasting at the same parameters for lipid oxidation, proximate, antioxidants, and essential oils. Results indicated that SHS roasted seeds yielded more oil (24.83 % vs only 23.23 % oil for convection) and had better peroxide value (highest value for convection, 84.00 versus SHS, 48.00 meq O2/kg of oil), p-anisidine value (highest value; for convection, 28.36 versus SHS, 23.73), FRAP values (SHS; 327 to 435 mM FeSO4/g sample, convection; 301 to 356 mM FeSO4/g sample), and DPPH scavenging capacity (SHS; 92.45 to 69.97 % inhibition, convection; 92.08 to 65.81 % inhibition). Results also indicate unsuitable extraction method and poor seed quality since oil oxidative analysis results were all above standard acceptable levels. Convection roasting also caused loss of thymoquinone, an important characteristic component of black seed essential oil. In the second phase, black seeds were TR and SHS roasted at 220℃ for 10 min. This roasting time and temperature was derived via response surface methodology for maximum antioxidant capacity.
Antibacterial Effects Of Phomopsidione Isolated From Diaporthe Fraxini Against Methicillin-resistant Staphylococcus Aureus (Mrsa) With Gene Expression And Metabolomics Profiling
(2023-08)
Wei, Yee Min
The rising prevalence of multidrug-resistant (MDR) pathogens has contributed to a high mortality rate due to overuse and misuse of antibiotics. Among the MDR pathogens, methicillin-resistant Staphylococcus aureus (MRSA) is the most threatening and poses the greatest impact on public health. Thus far, many bioactive ketone derivatives have been reported as anti-MRSA agents. Phomopsidione (C7H10O4), a bioactive ketone derivative isolated from Diaporthe fraxini, has previously demonstrated antibacterial effects. The present study was aimed to investigate the antibacterial and anti-biofilm effects of phomopsidione against MRSA and determine the phomopsidione-mediated modulation in virulence factors production. Additionally, the changes in gene expression and metabolites profile of MRSA in response to phomopsidione were examined. In broth microdilution assay, phomopsidione exhibited significant inhibitory activity against MRSA with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of 62.5 and 500.00 μg/mL, respectively. In crystal violet biofilm assay, phomopsidione inhibited and eradicated biofilm in a concentration-dependent manner. Phomopsidione showed significant reduction in the virulence factors production of MRSA at MIC and MBC when assessed using quantification of extracellular polymeric substances (EPS), catalase and lipase production assays.
Rheological Characterization And Fouling Mitigation Of Coconut Cream Emulsion
(2023-05)
Avan Farouq Qadir Maghazechi
This study aimed to understand and mitigate fouling deposition in CCE by investigating structural changes in heating surfaces and CCE bulk.
Synthesis And Performance Of Magnetic Chitosan Cellulose Nanocomposite Biosorbent From Oil Palm Empty Fruit Bunch For Heavy Metals Removal
(2023-08)
Khalid, Aina Mardhia
Heavy metals contamination especially in the aquatic environment poses severe environmental pollution concerns worldwide. Sources of heavy metals especially in textile industries has been discharging toxic heavy metals through the release of dyes into the environment during fibre dyeing and finishing processes. Individual wastewater treatment through physical, biological, or chemical method is often very costly and results in large amount of sludge. Thus, there is a need for alternative treatment processes that covers from pre to post wastewater treatment stage. Magnetic chitosan cellulose nanofiber (Mag-Chi-CNF) nanocomposite was synthesized from the isolated cellulose nanofiber by sol-gel technique. Several characterization methods were utilized to characterize the physicochemical, morphological, and thermal properties of the isolated Mag-Chi-CNF. Subsequently, the isolated Mag-Chi-CNF was utilized for single and simultaneous adsorption of heavy metals ions such as Cu(II), Cr(VI), and Pb(II) from synthetic aqueous solution. The adsorption was conducted by varying adsorption parameters such as pH, bio- sorbent doses, treatment time, and temperature. The surface morphologies of Mag- Chi-CNF revealed the porous structure that may enhance heavy metal adsorption, with average particle length of 500 ± 20 nm and width of 380 ± 12 nm, respectively. Thermal stability analysis shows the Mag-Chi-CNF have high thermal stability properties with thermal degradation temperature of 312 °C.
Halochlorella Rubescens Cultivation In Photobioreactors For Optimum Lipid Production
(2022-09)
Anbalagan, Lavanya
Lipids from microalgae have been studied for their potential application in various industries. The microalgae lipid production is mainly influenced by the cultivation methods and environmental conditions. This study investigates the effects of lipid content and lipid formation kinetics at different cultivation conditions involving pH, combination of nitrogen and phosphorus sources of different concentrations, carbon dioxide concentrations and light intensity on Halochlorella rubescens, a freshwater microalgae in photobioreactors with different configurations such as the cubic tank photobioreactor (CTPBR), centralized light photobioreactor (CLPBR) and tubular photobioreactor (TPBR) using one variable at a time (OVAT) method. The significance of differences between each test variable was determined using one way ANOVA where (p ˂ 0.05) is considered statistically significant. Qualitatively the lipid accumulation of cells was determined via Nile red staining method. The analysis of Fourier Transform Infrared Spectroscopy (FTIR) at different parameters confirmed the functional groups of lipids. The Leudeking-Piret model revealed that the lipid production of Halochlorella rubescens is growth-associated at all different cultivation conditions. The highest lipid content (39.42 ± 0.426%) and maximum biomass density (0.3662 ± 0.002 gL-1) was achieved at optimized conditions (pH 9, nitrogen-depleted medium, 15% CO2, 4000 lux) in 10L volume using TPBR.

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