Universiti Malaysia Terengganu Journal of Undergraduate Research

Microbiological assessment of soy milk collected from bazar Ramadhan in Kuala Nerus, Terengganu

Salma Hashim, Nurfarhana Rosli, Siti Nor Khadijah Addis — Wed, 30 Apr 2025 00:00:00 +0800

Soy milk is a popular non-dairy milk alternative, often consumed for its high protein content and health benefits. Despite its growing popularity, there are concerns about the quality and safety of soy milk. Soy milk sold in the bazaar Ramadhan is usually home-prepared by the small-scale industry. Nonetheless, this soy milk is often unpasteurized and prepared with no preservatives, making them easily contaminated. The objective of this study was to conduct microbiological assessments of soymilk samples from the bazaar Ramadhan in Kuala Nerus. A number of 48 soy milk were randomly bought from the bazaar Ramadhan Gong Badak, Kuala Nerus from 20th May to 10th June 2018. The Total Plate Count method was used to determine the number of bacteria present in the soy milk. In contrast, XLD agar and BBL Crystal Kit were used to identify the isolated bacteria. In this study, the highest bacteria number of 9.71 ± 0.04 Log 10 CFU/ml was found which was 116% exceeding the allowable count of bacteria in soy beverages (4.5 Log 10 CFU/ml) and the lowest was 2.81 ± 0.08 Log 10 CFU/ml. Moreover, 62.5% of the samples contain various bacteria including coliform bacteria, Salmonella sp., and Pseudomonas sp. This study shows that soy milk may be harmful for consumption, leading to more serious food contamination issues. This warrants regular screening and observation of food and beverages sold in markets and bazaar Ramadhan to enforce food safety and security measures.

Phytochemical study on black pepper berries (Piper nigrum L.)

Nurul Huda Abdul Wahab, Ahmad Nazif Aziz, Nirosha Ramesh — Wed, 30 Apr 2025 00:00:00 +0800

Black pepper is one of the well-known spices rich in aromatic and medicinal components, along with substantial levels of several other functional components that have health-promoting properties. The use of black pepper has been recorded in various fields such as traditional medicine, food processing, and the pharmaceutical industry. It is also recognised as an important source of natural antioxidants that have anticarcinogenic properties. In this study, a chemical investigation using black pepper berries (Piper nigrum) was conducted. The purpose of doing that is to determine the chemical component of this species. The sequential maceration extraction methods utilising solvents with different polarities, namely hexane, dichloromethane, and methanol, yielded the corresponding crude extracts. The quantitative phytochemical analysis was performed on the crude extracts. Separation and isolation work was focused on the dichloromethane crude extract using Thin Layer Chromatography (TLC), Column Chromatography (CC), and Preparative Thin Layer Chromatography (PTLC). The outcomes revealed that the berries of P. nigrum contained alkaloid, terpenoid, steroid, and flavonoid metabolites. Two semi-pure compounds have been isolated from the dichloromethane crude extract. The obtained compounds were analysed using Fourier Transform Infrared (FTIR) spectroscopy and Ultraviolet-Visible (UV-Vis) spectrophotometer. Based on the FTIR spectrums and previous studies, these semi-pure compounds, K1A (2) and K3C (3), are expected to be 2, 4-di-tert-butylphenol and ethyl linoleate, respectively. This significant data provides preliminary findings that may lead to further purification and structure determination as a potential source of herbal medicinal compounds.

Analyzing the Impact of Various Diesel Types on The Performance and Emissions of Marine Diesel Engines Using Diesel-RK Software

Che Wan Mohd Noor, MOHD HAFIZUDDIN — Wed, 30 Apr 2025 00:00:00 +0800

Software applications to solve engineering problems and performance issues of marine diesel engines are becoming easier in current trends due to the rapid development of technology and computer science. However, the cost of software kits for users is very high and burdensome, especially for researchers in developing countries. Alternatively, Diesel-RK software is an open-source program created to help researchers in modelling and making predictions on the performance and exhaust emissions of a diesel engine. Therefore, this work presents the results of the Diesel-RK application for simulating performance, emissions, and the capability of use of another type of diesel by marine diesel engines of 4-cycle-inlined 6-cylinder, and suggests the best type of diesel fuel for testing on an actual marine engine. Different types of diesel fuel, such as Light Fuel Oil 1 (LFO-1), Diesel No. 2, EN590, and Heavy Fuel Oil, were tested in this simulation. The engine performance and emission parameters, such as brake power, torque, specific fuel consumption, thermal efficiency, Nitrogen Oxide (NOx) emissions, and Carbon Dioxide (CO2) emissions, were analysed. The research indicated that utilising EN590 fuel resulted in enhanced marine diesel engine performance, including improved brake power, torque, thermal efficiency, and fuel consumption. Moreover, EN590 fuel exhibited significantly reduced NOx and CO2 emissions compared to Diesel No.2, LFO-1, and Heavy Fuel, offering valuable guidance for both simulation and practical engine studies.

Analysis of Living Cost by Countries Using Vine Copula

Wendy Shinyie Ling, Redza-Safwan Khairuddin — Wed, 30 Apr 2025 00:00:00 +0800

Living cost is defined as the amount of money needed to cover expenses for essential needs. At the onset of the pandemic, the cost of living rose while wages stagnated. As a result, people lost jobs. Therefore, this research aims to perform copula modelling for five variables; living cost, monthly wages, cost index, inflation rate, and purchasing power. A better understanding of the cost of living can help reduce future losses and enhance sustainable economic growth and employment. In this study, we conducted a living cost analysis using marginal distribution to generate a pseudo-observation. Then, we build the vine copula models, which are Regular vine (R-vine), Drawable vine (D-vine), and Canonical vine (C-vine). Then, we obtain and compare the Akaike Information Criterion (AIC) for the three models to determine the best-fitted model. The results of AIC reveal that both C-vine and D-vine are suitable for modelling living cost analysis.

Lindley’s Approximation in Estimating Two-Parameters Inverted Weighted Exponential Distribution

HANI SYAHIDA ZULKAFLI, FATIN SYAZWANI NAZRI — Wed, 30 Apr 2025 00:00:00 +0800

The Inverted Weighted Exponential distribution can be used to describe and model real life phenomena with unimodal or decreasing failure rates. The main aim of this study is to use Bayesian approach to estimate the two parameters of the distribution. Two loss functions are ussed; squared error loss function (SELF) and linear exponential loss (LINEX) function with Lindley's method. The bias and RMSE is reviewed to assess the performance of the estimation method. Via simulation studies, the results show that the scale parameter benefited from using Bayesian approach with squared error loss function.

Radiographic Imaging Application in Capturing Nest Escaping Movement by Sea Turtle Hatchlings

Syam Samsol, Irwan Iskandar Jusoh, Mohd Uzair Rusli — Wed, 30 Apr 2025 00:00:00 +0800

Nest escaping is a vital process that takes up a significant amount of energy and time during the early life of sea turtle hatchlings. Previous studies have shown how hatchlings benefit from this aggregation behaviour while digging upward in the nested column. However, there is a lack of information on the relationship between the dimensions of nest escaping movement formation. This study explores the potential of radiographic imaging in capturing the dimension of digging formation to relate its potential with the energy conservation mechanism. This article describes the challenges and prospects of capturing hatchlings’ movement while digging up and escaping their underground nest via radiographic imaging (X-ray). Several trials have been conducted to seek the most suitable approach to be applied as a standard method for future studies. We developed an open-respirometry chamber with a supply of oxygen for egg incubation according to preferred clutch sizes to meet one of the objectives, which is to determine the effect of clutch sizes on the dimension of digging formation. Exposure usage of 125 kV, 40.0 mAs, and 62.5 ms were determined to produce significant X-ray images. Additionally, iron flux has been determined to be useful in measuring hatchlings’ digging progress, as it has the potential to enhance our image quality and observation. We were able to observe the position of the hatchlings with such development. Nevertheless, we do not know the accurate dimension of digging movement formation as modelled by the hatchlings.

Effect of Sucrose Concentration on Proliferation of Bucephalandra Sp. ‘Red-Mini’ Cultures

NURFARHA MUHAMAD ZALAN, MOHAMAD FAIRUZ NOOR HASSIM, AZIZ AHMAD — Wed, 30 Apr 2025 00:00:00 +0800

Bucephalandra sp. ‘Red Mini’ is an aquatic flowering plant endemic to Borneo Island. The plant is popular among aquarists due to its magnificent appearance underwater submergence. Its vegetative propagation is relatively slow. Thus, applying the tissue culture technique could increase the production of diseased-free plantlets in large quantities within a short period. To date, limited reports are available on the effects of sucrose on the multiplication of Bucephalandra sp. ‘Red Mini’. Therefore, this study investigated the effects of sucrose concentration on the number of shoot tips and reduced sugar content of Bucephalandra sp. ‘Red Mini’ cultures. The plantlets were cultured in MS medium containing various sucrose concentrations 1%, 3%, or 5% (w/v) added with 0 or 0.5 mg/L of Thidiazuron (TDZ), respectively. The newly formed shoot tips were recorded every two weeks intervals for 10 weeks and subsequently measured for the reducing sugar content. Results revealed that the new shoot tip number produced and the reduced sugar content were influenced by sucrose concentration and the presence of TDZ in the media. The highest shoot tip was recorded in the treatment medium containing 5.0% (w/v) sucrose added with 0.1 mg/L TDZ. In this medium, the shoot tip produced and reducing sugar content were 23.3 ± 4.0 shoot tips/culture and 0.35 ± 0.01 mM/culture, respectively. The finding suggested that sucrose concentration and TDZ synergistically regulate the formation of new shoot tips of Bucephalandra sp. ‘Red Mini’ and the reduced sugar content in the explants.

Corporate Governance and Carbon Emission Performance: Evidence in Malaysian

NUR ATHIRAH MOHD ANUA , SITI NURAIN MUHMAD — Wed, 30 Apr 2025 00:00:00 +0800

This research delves into the intersection of corporate governance and carbon emission performance in Malaysia, shedding light on the pivotal role governance practices play in fostering environmental sustainability. The primary objective of this study is to investigate how key corporate governance mechanisms, namely CEO duality, Board size, and Board meetings, influence carbon emissions performance in the Malaysian context. This study employs panel data regression, and the results indicate a positive correlation between Carbon Dioxide (CO2) emissions and all other variables in the dataset. This implies that as CO2 emissions increase, there is a tendency for the other variables [board size, CEO-chairman duality, board meetings, and Return on Assets (ROA)] to also increase. In regression findings, CEO-duality does not significantly impact corporate governance, while a larger board size and more frequent board meetings positively influence effective corporate governance for decarbonisation. Surprisingly, lower ROA percentages are associated with better decarbonisation performance in firms. This suggests that, despite CEO-duality being less relevant, board-related factors and ROA play significant roles in the relationship between corporate governance and decarbonisation efforts. The study underscores the importance of viewing carbon emissions as a critical corporate outcome, encouraging companies to prioritise and improve their carbon emission performance. Particularly for firms facing less pressure from the takeover market, the study advocates for implementing policies to mitigate carbon emissions, recognising the growing global concern surrounding climate change. The government should enhance the regulatory framework by updating the Companies Act and ensuring stricter compliance with the Malaysian Code on Corporate Governance (MCCG). Strengthening corporate governance in Malaysia can enhance transparency and accountability in carbon emission reporting, encouraging companies to adopt sustainable practices.

Facile Methods for Diesel/Biodiesel Blend Ratio Determination in Rubber Seed Methyl Ester

Wed, 30 Apr 2025 00:00:00 +0800

Biodiesel is recognised as a highly sustainable alternative bioenergy to mitigate the adverse impacts of fossil fuel use. Blending biodiesel into diesel fuel at specific ratios has been mandated in various countries. In this regard, the study intends to determine the diesel or biodiesel blend ratio in rubber seed methyl ester using several facile methods. The processes of acid-catalysed esterification and base-catalysed transesterification were employed to produce 92.60% rubber seed methyl ester. A series of diesel/biodiesel blends of B20, B40, B60, and B80 were prepared by mixing the biodiesel with pure diesel. Euro 5 (B7) was obtained from the local petrol station for analysis. B80 showed the highest value for several tested parameters, including an acid value of 0.3927 mg KOH/g, a peroxide value of 8.7464 meq/kg, and a density of 0.8701 g/cm3. Meanwhile, Euro 5 (B7) achieved the highest refractive index and UV absorbance values at 1.4601 nD and 0.927, respectively. Moreover, good linearity was observed for all tested parameters with R2 values between 0.9097 and 0.9993, validating them as strong indicators for the determination of blend ratio, except for the refractive index, which showed an R2 value of 0.6366. However, all tested parameters met the criteria outlined in the EN/ASTM standard methods. Thus, this study helps to provide an approach for related industries to validate the percentage blend claims made by other parties in minimal time.

The Impact of Macroeconomic Variables on Stock Prices: A Case Study from FTSE Bursa Malaysia KLCI from 1994 until 2022

Wed, 30 Apr 2025 00:00:00 +0800

This study uses monthly historical data to analyse the effects of changes in selected macroeconomic variables on the stock prices of the FTSE Bursa Malaysia KLCI from 1994 to 2022. A multiple regression model employing Ordinary Least Squares (OLS) and the Granger Causality test are employed to study this relationship. Upon evaluating the estimated regression coefficients and corresponding t-statistics, the findings reveal changes in the prices of Brent Crude Oil (BC) futures. Meanwhile, the Currency Exchange Rates (CR) indicate a significantly positive influence on stock prices. In contrast, the rates of Gross Domestic Product (GDP), Interest Rates (IR), and Inflation Rates (CPI) do not significantly influence stock prices. Additionally, unidirectional Granger Causality is observed between stock prices, the rates of GDP, and the CR.