Borneo Science | The Journal of Science and Technology

BEYOND ANTIBIOTICS: PROBIOTICS, PREBIOTICS, AND SYMBIOTICS IN FRESHWATER AQUACULTURE – A REVIEW

Wed, 31 Dec 2025 00:00:00 +0800

Aquaculture remains the fastest-growing sector in global food production, providing a vital source of protein and supporting economic development. In Malaysia, freshwater aquaculture particularly the farming of Clarias gariepinus is central to food security, yet the intensification of production has heightened disease risks, feed inefficiencies, and vulnerability to bacterial pathogens such as Aeromonas hydrophila. Conventional use of antibiotics has proven unsustainable due to antimicrobial resistance and environmental concerns, driving the need for alternative management strategies. Functional feed additives, including probiotics, prebiotics, and synbiotics, have emerged as eco-friendly approaches to enhance growth performance, feed utilization, immune competence, and pathogen resistance. The aim of this review is to critically evaluate recent progress (2015–2025) in the use of probiotics, prebiotics, and synbiotics in freshwater aquaculture, with a particular focus on catfish farming in Malaysia. It highlights their types, mechanisms of action, comparative effects on fish growth and immune modulation, and their role in disease resistance against A. hydrophila. By synthesizing current evidence, the review identifies both the opportunities and research gaps associated with these functional feed additives. The findings underscore their potential as sustainable alternatives to antibiotics, supporting healthier and more resilient aquaculture systems.

RECOMBINANT PHYTASE: ADVANCES IN PRODUCTION STRATEGIES AND INDUSTRIAL APPLICATIONS – A REVIEW

Sk Amir Hossain — Wed, 31 Dec 2025 00:00:00 +0800

As the demand for efficient and sustainable feed and food production continues to rise globally, phytase has become a vital enzyme in biotechnology due to its ability to hydrolyze phytic acid and enhance phosphorus bioavailability. Recent advances in genetic engineering, protein design, and molecular biology have significantly accelerated the development of high-yield and functionally enhanced phytase variants. A wide range of expression systems including bacterial, fungal, and yeast-based platforms have been extensively studied to improve catalytic efficiency, enzyme stability, and production yields under industrial conditions. Recombinant DNA technologies now allow precise modification of phytase genes for expression in intracellular, extracellular, or cell surface display formats, each offering unique advantages. Among these, cell surface display systems are gaining particular attention for their ability to anchor phytase directly onto microbial surfaces, simplifying purification and reducing downstream processing costs. Additionally, integration of synthetic biology tools, codon optimization, and promoter engineering has led to improved phytase production under harsh conditions such as high temperature or low pH. This review provides a comprehensive overview of current recombinant phytase production strategies, critically evaluating the advantages and limitations of various host systems and expression formats. Key factors influencing large-scale production are also discussed, with a focus on optimizing expression systems for industrial application. By addressing both technological innovations and production challenges, this review aims to support the development of more efficient, cost-effective, and environmentally sustainable phytase production platforms.

Biogas Recovery and Waste Reduction from Kitchen Food Waste by Using Anaerobic Digestion

Newati Wid — Mon, 03 Nov 2025 00:00:00 +0800

Kitchen food waste is defined as food that is left over or wasted during the production, processing, distribution, procurement, preparation, and consumption processes. About 50% of all food waste is reportedly to originate from kitchens and since it can decompose, food waste is regarded as degradable kitchen waste. In Malaysia, about 15,000 tonnes per day kitchen food waste generated and has the potential to produce hazardous gases, leachate, air pollution from food decay and quickly expanding landfills. In this study, kitchen food waste was used to recover biogas using anaerobic digestion. Additionally, the volume of waste reduced was also investigated to prove that anaerobic digestion is not only to recover resources, but also to reduce waste generation. The anaerobic digestion was performed at pH value of pH6.8-7.2 and temperature 37^oC for 15 days. Two (2) different samples of kitchen waste were used namely, shallots and cabbage. The biogas recovery was determined using water displacement technique. Kitchen food waste was also characterized before and after anaerobic digestion in terms of total solids, volatile solids and pH value. It is found that the percentage of total solids for shallots and cabbage before anaerobic digestion were 19.9% and 16.8%, respectively, and the percentage of volatile solids before anaerobic digestion were 88.1% and 95.6%, respectively. After anaerobic digestion, the percentage of total solids for shallots and cabbage were 15.5% and 13.6%, respectively, and the percentage of volatile solids were 21.0% and 15.2%, respectively. This suggests that the total and volatile solids of shallots and cabbage were reduced with 22.11% and 19.5%, and 76.14% and 84.14%, respectively, after performing anaerobic digestion. While 168mL and 52mL of biogas can be recovered from shallots and cabbage, respectively, throughout 15 days anaerobic digestion. This shows that anaerobic digestion is not only to recover biogas but also to reduce waste.

ADSORPTION BEHAVIOR OF Cu(II), Pb(II), AND Zn(II) ON SELECTED NATURAL SOILS IN SABAH

WEI HSIANG TAN, SITI AISHAH MOHD ALI, LOUMI SURUGAU — Mon, 03 Nov 2025 00:00:00 +0800

Heavy metals in soil can reduce plant fertility and may pose health risks to those who consume the affected plants. Therefore, understanding the soil's ability to retain heavy metals is essential. This study explores the adsorption behaviors of Cu(II), Pb(II), and Zn(II) ions in selected natural soil samples from Sabah, providing insights into their retention capacities and potential environmental implications. The adsorption isotherms were measured using the conventional batch adsorption technique. The results indicate that the adsorption isotherms are satisfactorily described by both the Langmuir and Freundlich models, with R² values mostly exceeding 0.93. Hilltop soil (clay loam) demonstrated the greatest adsorption capacity, exhibiting a distinct metal ion affinity sequence of Cu²⁺ > Pb²⁺ > Zn²⁺. In contrast, clayey sand soils from orchards, rubber plantations, and foothill regions showed a preferential adsorption for Zn²⁺ over Pb²⁺ and Cu²⁺. Despite sharing similar soil classifications, these variations highlight the influence of site-specific properties on metal ion adsorption behavior. It is found that soil adsorption behavior is shaped by mineralogical composition, particle size distribution, organic matter content, pH level, specific surface area and land management practices. These elements influence both the availability of adsorption sites and the order in which adsorption takes place, ultimately determining the soil’s capacity to retain and immobilize substances like heavy metals.

GROWTH AND HEAVY METAL CONTENT IN TWO ROSELLE VARIETIES CULTIVATED UNDER DIFFERENT TYPES OF SOIL MEDIA

SITI AISHAH MOHD ALI, Tan, Sahibin Abd. Rahim, Rohana Tair — Mon, 29 Sep 2025 00:00:00 +0800

The phenolic content of plants often varies in response to environmental changes and genetic factors. The rise in anthropogenic activities in recent times has led to an increase in the level of heavy metals in the environment. The excessive number of heavy metals may lead to bioaccumulation in the ecosystem, which plants absorb from the environment. Therefore, this study will be carried out to investigate the influences of different soil type treatments (ultrabasic, clay, and organic soil) on plant growth, phenolic constituents’ production, and selected heavy metal content (Zn, Cd, Co, Cu, Ni, Cr, Pb, and Mn) in two Roselle varieties (H. sabdariffa L. and H. sabdariffa var. UMKL-1). The growth parameters, including plant height, stem diameter, number of branches, and leaf count, were recorded. Roselle calyx extract was analyzed for heavy metal concentrations using Inductively Coupled Plasma - Optical Emission Spectrometry. The result showed there is no significant effect recorded on the growth parameter with different soil types of treatment (p > 0.05) and between varieties. In general, all plant growth parameters showed an increasing trend throughout 84 days after transplanting for the roselle variety. In addition, heavy metal results indicated that Mn and Zn were the predominant heavy metals accumulated in both varieties. Roselle varieties cultivated using ultrabasic soil have higher Mn, Co, Ni, and Pb concentrations, and clay soil has higher Zn, Cu, Cr, and Cd concentrations. Conversely, organic soil has the lowest heavy metal content. It can be concluded that both varieties of cultivation using organic soil may produce better growth and lower heavy metal content in calyces.

INSIDE THE CHEMICAL PROPERTIES AND SURFACE MORPHOLOGY OF ENR/PVC FILLED CELLULOSE GRAFTED PMMA MEMBRANE

Mohd Razali bin Shamsuddin, Muhammad Nur Rashidi Rosli — Wed, 31 Dec 2025 00:00:00 +0800

The ENR/PVC thin film has great potential as a membrane due to its ideal owing to unique characteristics such as freestanding, high-pressure resistance, and durability over time but low porosity. This research aims to investigate inside into chemical and morphological properties of developed composite epoxidized natural rubber with polyvinyl chloride-filled cellulose grafted polymethyl methacrylate (ENR/PVC/cellulose-g-PMMA) membrane. Solution blending of 60:40 wt. % ENR/PVC 10 % w/v of filler were mixed homogeneously for 24h stirring in THF solution. The membranes were cast onto a glass plate and the phase inversion technique was used to prepare ENR/PVC/Cell-g-PMMA membranes. The characterization of chemical properties was carried out by Fourier transform infrared spectroscopy (FTIR) to determine functional groups related to bond breaking and the formation of new bonds of the species during grafting copolymerization and membrane fabrication. Variable pressure scanning electron microscopy (VPSEM) was conducted to determine surface morphology and textural properties of fillers and membranes. Furthermore, it contributes to porosity and the formation of pores on the membrane. FTIR spectrum shows that absorption peaks around the range 1735-1725 cm^-1 of the carbonyl ester -C=O functional group have been detected and proven successful of the grafting method between cellulose and PMMA. The rough surface of fibers, formation of open pores, and interspace structure between ENR/PVC matrix and filler affirmed the addition of cell-g-PMMA fillers caused by film-filler and filler-filler interfaces interaction as shown by the VPSEM micrograph. In summary, the chemical properties and morphological analysis give useful information on the effectiveness of potential ENR/PVC/Cell-g-PMMA membranes in developing standalone, highly pressure-resistant, porous, and elastic membranes.

SUSTAINABLE THE IMPACT OF INDOOR AIR QUALITY ON OCCUPANCY STRESS LEVEL IN WARSHIP: SYSTEMATIC LITERATURE REVIEW

muhammad hisham abdul halim, Asmat Ismail, Siti Rasidah MD Sakip — Wed, 31 Dec 2025 00:00:00 +0800

Indoor air quality (IAQ) plays a critical role in influencing the health, comfort, and psychological performance of individuals operating in enclosed and confine space such as warships. However, research regarding the impact of IAQ on occupancy stress level in warship remains challenging due to the limited number of studies. Therefore, this study aims to conduct a systematic literature review on the impact of IAQ on stress levels among warship crew. The methodology is based on a systematic literature review that employs the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A comprehensive search was conducted across Scopus, Google Scholar, Web of Science, ProQuest, and ScienceDirect databases, covering literature published between 2020 and 2025. The review process includes three main methodological steps: identification, screening, and eligibility, followed by the PRISMA checklist. Three key themes were found: (a) IAQ– physical parameter and indoor air contaminant, (b) Self-efficacy– vicarious experience and performance outcomes, and (c) Stress – response and trigger. A factor analysis confirmed the validity of the thematic structure and reinforced the interconnection between environmental conditions and psychological outcomes. The findings provide valuable knowledge gaps for future studies. This review supports Environmental, Social, and Governance (ESG) principles by advocating for sustainable and health-centric practices in maritime environment

HEALTH RISK ASSESSMENT OF HEAVY METAL IN FISH TO THE POPULATION IN PETAGAS RIVER, SABAH

MUHAMMAD NUR RASHIDI BIN ROSLI — Wed, 31 Dec 2025 00:00:00 +0800

The levels of heavy metal in marine environment and fish are very crucial for the assessment of heavy metal contamination which poses deleterious effect towards communities, especially those in Petagas River. Four randomly caught fish species (Sagor Catfish, Indo-Pacific Tarpon, Spotted Catfish and Nile Tilapia) from the river were dissected to obtain the fish flesh and prepared by following the Protocol of Perkin Elmer Pure Atomic Spectroscopy Standard (2001). The water sample and fish flesh sample were analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to identify the heavy metal concentration that affect the level of metal contaminants. The highest average of heavy metal concentration was found in Potassium (K) 10.04 µg/L, followed by Arsenic (As) 0.46 µg/L and Lead (Pb) 0.63 µg/L in the water sample. For fish sample the highest average concentration of heavy metal was found in Potassium (K) 14.28 µg/g, followed by Arsenic (As) 1.33 µg/g and Lead (Pb) 1.14 µg/g. The result obtained from ICP-MS was compared with the guidelines that have been set by the Malaysian Food Act (1983) and Regulation (1985), Malaysian Interim Water Quality Standard (NWQS) (2008), World Health Organization (WHO) and the Food and Agriculture Organization (FAO). The present study demonstrates rather high heavy metal concentration in water for As and Pb that exceeded the permissible limit set by NWQS (2008) (0.05 mg/L) and (0.01 mg/L) and FAO/WHO (2017) (0.01 mg/L) and (0.01 mg/L) respectively. However, the K concentration did not exceed the permissible limit set by FAO/WHO (2017) (12.0 mg/L) and no data published for K in NWQS (2008). The present study for heavy metal concentration for As and K elements in fish sample were found to exceed the permissible limit set by MFAR (1983 & 1985) (1.0 µg/g) and (no limit published for K) and FAO/WHO (1984) (0.1 µg/g) and (1.6 – 2.0 µg/g) respectively. The Pb concentration in fish sample did not exceed the permissible limit set by MFAR (1983 & 1985) but it exceeded the permissible limit set by FAO/WHO (1984) (0.2 µg/g).

SENTIMENT ANALYSIS OF PUBLIC HEALTH SOCIAL MEDIA COMMENT USING EXPERT ANNOTATION

Daimler Benz Alebaba, Suaini Sura, Nooralisa Mohd Tuah, Nona Masnie Mohd Nistah — Wed, 21 Jan 2026 00:00:00 +0800

Sentiment analysis has become a critical tool for organizations and researchers to understand user sentiment. However, it faces challenges such as managing noisy data, interpreting sarcasm or irony, and adapting to the evolving nature of language, especially in public health where users often express opinions about their health conditions, healthcare experiences, and complex medical terminology on various topics. Addressing these challenges is crucial to maintaining the integrity of sentiment analysis results. Hence, this study analyzes public health social media user comments using a structured sentiment analysis framework. The framework includes dataset collection and annotation, text preprocessing, feature vectorization, and text classification. The results show the model achieved 98% accuracy, demonstrating strong predictive performance. This accuracy falls within the 'Excellent Classification' range which is widely recognized as an industry standard for high-performing models, indicating that the model is not only accurate but operates with a level of precision and recall that exceeds the benchmarks typically required in practical applications.

AN SOR METHOD UTILIZING REDLICH-KISTER FINITE DIFFERENCE FOR TWO POINT BOUNDARY VALUE PROBLEMS

Mohd Norfadli Suardi, JUMAT SULAIMAN — Tue, 30 Dec 2025 00:00:00 +0800

This study presents a numerical method using a second-order Redlich-Kister Finite Difference (RKFD) discretization scheme to approximate the two-point boundary value problems (TPBVPs). The approach creates a linear system for the given problem by using the first two derivatives to create the RKFD approximation equation. Two iterative approaches are used to solve the linear system: Gauss-Seidel (GS) and Successive Over Relaxation (SOR). Two model examples that assess each approach according to its number of iterations, execution time, and maximum norm over five different mesh sizes indicate the effectiveness of these proposed iterative methods. The results show that the SOR method outperforms the GS methods in providing an extremely accurate approximation of the known exact solution.