Semarak Proceedings of Natural and Environmental Sciences
Semarak Proceedings of Natural and Environmental Sciences (SPNES) is an international forum for the publication and dissemination of original work which contributes to greater scientific understanding in the area of applied sciences and engineering technology. The Journals reports principally the achievements spanning the interdisciplinary field of applied researches. Scope of the journal includes: biology, chemistry, physics, environmental, health science, mathematics and statistics, geology, engineering, computer science, natural and technological sciences, medicine, and architecture.
Temporal Changes in Seaweed Diversity and Abundance at Pulau Merambong, Johor: Progress and Impacts of Land Reclamation From 2014 to 2025
Merambong Island is rich in seaweed biodiversity, despite ongoing long-term environmental disturbances such as land reclamation and shipping activities. This study assessed the temporal changes in seaweed diversity and abundance in Merambong Island from 2014 to 2025, focusing on progress and ecological impacts from the land reclamation for Forest City development. Physical specimens that were growing as epipsammic, epiphytic, epilithic, epizooic, and epipelic as well as on artificial substrate were collected using a destructive line transect-quadrat method. A total of 86 seaweed species have been recorded from 2014 to 2025, across five survey years representing pre-reclamation (2014), during reclamation (2016), and three post-reclamation periods (2019, early 2024 and late 2024). One-way ANOVA showed significant differences, where p = 0.01 (p < 0.05) that indicated substantial temporal variation. Cladophora stimpsonii was identified as the dominant species in Merambong Island for the recent observation in late 2024. The successfully acclimatized species throughout 2014 to 2025 observation were Avrainvillea erecta, Caulerpa sertularioides, Gracilaria salicornia, Hypnea spinella and Padina minor. Thirteen genera (Acanthophora, Avrainvillea, Bryopsis, Caulerpa, Cladophora, Dictyota, Halimeda, Jania, Laurencia, Padina, Sargassum, Tolypiocladia, and Ulva) were only observed pre-, during and post-reclamation but were absent from the most recent observation in late 2024, suggesting that they are sensitive to environmental disturbances. Comparative analysis pre-reclamation (2014) and post-reclamation (early 2024) indicated a decline in seaweed diversity. However, by late 2024 there was evidence of ongoing recovery of opportunistic species such as Caulerpa lentillifera. Long term monitoring revealed significant changes in species composition, spatial coverage and community structure throughout the environmental disturbance.
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Penggunaan Cengkih (Syzygium aromatica) Dalam Menurunkan Bilangan Bakteria Serta Cadangan Aktiviti Secara In Siliko
Cengkih (Syzygium aromaticum) merupakan rempah yang sering digunakan dalam masakan namun mempunyai kandungan fitokimia yang berperanan menghalang pertumbuhan bakteria. Kajian ini dilakukan bagi membuktikan kebolehan cengkih dalam mengurangkan bilangan bakteria daripada sampel air liur berbanding bahan kumuran komersial. Selain itu, cadangan aktiviti pengurangan bilangan bakteria dikenalpasti menggunakan pendekatan secara in siliko. Bilangan bakteria dibandingkan berdasarkan unit pembentukan koloni dalam air liur sebelum dan selepas 30 minit kunyahan dengan cengkih atau bahan kumur komersial sebagai kawalan. Hasil menunjukkan purata unit pembentukan koloni (upk) sebelum kunyahan cengkih adalah sebanyak 2.86×106 upk/mL dan menurun kepada 2.16×106 upk/mL selepas kunyahan dengan cengkih. Penurunan bilangan koloni bakteria sebelum dan selepas kunyahan cengkih adalah signifikan (p<0.05) dengan nilai p=0.030. Bilangan purata koloni sebelum menggunakan ubat kumur pula adalah 2.13 ×106 upk/mL dan selepas menggunakan ubat kumur adalah 1.22 ×106 upk/mL dengan nilai p=0.001 (p<0.05). Penurunan bilangan koloni bakteria adalah juga signifikan selepas penggunaan ubat kumur. Bakteria yang berjaya dipencilkan terdiri kebanyakannya daripada Streptococcus sp. dan Staphylococcus sp., yang sering ditemui dalam mulut manusia. Interaksi fitokimia terhadap enzim lisozim serta protein bakteria serta kesan juga dilaksanakan. Sebatian fitokimia utama cengkih iaitu eugenol dilakukan pendokan dengan lisozim menunjukkan terdapat interaksi dengan skor afiniti sebanyak -5.4 kCal/mol yang mencadangkan kemampuannya meningkatkan aktiviti enzim lisozim yang membantu membunuh bakteria mulut. Selain itu terdapat dua tapak pelekatan yang berbeza antara protein adhesin P1 Streptococcus mutans dengan eugenol dengan afiniti pelekatan -5.1 kCal/mol dan -3.89 kCal/mol. Kesan pengikatan ini boleh mengganggu kestabilan protein-ligan yang terbentuk yang boleh menjejaskan fungsi pelekatan bakteria. Clove (Syzygium aromaticum) is a spice that is often used in cooking but has phytochemicals that inhibit bacterial growth. This study was conducted to prove the ability of cloves to reduce the number of bacteria in saliva samples compared to commercial mouthwashes. In addition, the proposed activity of reducing the number of bacteria was identified using an in silico approach. The number of bacteria was compared based on colony forming units in saliva before and after 30 minutes of chewing with cloves or commercial mouthwash as a control. The results showed that the average colony forming units (CFU) before chewing cloves was 2.86×106 CFU/mL and decreased to 2.16×106 CFU/mL after chewing cloves. The decrease in the number of bacterial colonies before and after chewing cloves was significant (p<0.05) with a p value of 0.030. The average number of colonies before using the mouthwash was 2.13 ×106 cfu/mL and after using the mouthwash was 1.22 ×106 cfu/mL with a p value of 0.001 (p<0.05). The decrease in the number of bacterial colonies was also significant after using the mouthwash. The bacteria that were successfully isolated consisted mostly of Streptococcus sp. and Staphylococcus sp., which are often found in the human mouth. Phytochemical interactions with lysozyme enzymes and bacterial proteins and effects were also carried out. The main phytochemical compound of cloves, eugenol, was docked with lysozyme showing an interaction with an affinity score of -5.4 kCal/mol which suggests its ability to increase the activity of the lysozyme enzyme which helps kill oral bacteria. In addition, there are two different adhesion sites between the adhesin protein P1 of Streptococcus mutans with eugenol with an adhesion affinity of -5.1 kCal/mol and -3.89 kCal/mol. This binding effect can disrupt the stability of the formed protein-ligands which can affect the adhesion function of bacteria.
Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction Genotyping of Extended-Spectrum Beta-Lactamase - Producing Klebsiella pneumoniae Strains from A Malaysian Teaching Hospital
Klebsiella pneumoniae (KP) is a major cause of hospital-acquired infections (HAIs). The bacteria can acquire plasmids encoding Extended-Spectrum Beta-Lactamases (ESBL) that confer resistance to many antibiotics and lead to treatment failure. This study aimed to determine the prevalence of five ESBL genes (blaTEM + blaCTX-M-1 + blaCTX-M-9 + blaSHV + blaOXA-1) and the genetic relatedness of ESBLKP strains isolated from Hospital Canselor Tuanku Muhriz (HCTM), the teaching hospital of Universiti Kebangsaan Malaysia. From December 2023 to May 2024, 31 ESBLKP strains and their antibiotic susceptibility testing (AST) results were obtained from the Department of Diagnostic Laboratory Services. ESBL genotyping was performed using the Polymerase Chain Reaction (PCR), and Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR) was carried out on strains exhibiting the three most common AST profiles. Tested strains were resistant to 3rd -generation cephalosporins, with notable resistance to cefepime (90.3%), amoxicillin-clavulanate (83.9%), ampicillin-sulbactam (67.7%), and ciprofloxacin (51.6%). Worryingly, three strains were carbapenem-resistant. The most prevalent ESBL genes were blaSHV (100%) and blaCTX-M-1 (90.3%), while 54.8% of the strains carried the combination blaTEM + blaCTX-M-1 + blaSHV . ERIC-PCR revealed four main clusters with 70% similarity. Our findings demonstrate a high prevalence of blaSHV and blaCTX-M-1 also highlight the genetic diversity of ESBLKP strains isolated from HCTM patients. In addition to monitoring AST trends, continuous genetic surveillance of ESBLKP will be important.
Microbial Contamination of Airborne Particulate Matter (PM2.5 and PM10) In Kuala Lumpur’s Ambient Air
Regional haze episodes frequently affect developing countries, causing severe air pollution and potential health risks. However, conventional air quality monitoring often overlooks the biological components of airborne particulate matter (PM). This study investigates microbial contamination associated with fine (PM₂.₅) and coarse (PM₁₀) particulates in Kuala Lumpur during the Southwest Monsoon and Inter-monsoon II periods. Samples were collected using High Volume (HVS) and Low Volume Samplers (LVS) equipped with glass microfibre filters. Culture-based enumeration on Tryptone Soy Agar (TSA) and shotgun metagenomic sequencing were performed to quantify bacterial loads and characterize community composition. The highest bacterial counts in PM10 were recorded during the Southwest Monsoon and Inter-monsoon II, at 5.42 ± 0.49 and 5.40 ± 0.73 log CFU/g, respectively. No significant differences were observed between monsoon periods (p > 0.05), and bacterial abundance was not correlated with PM concentration. Metagenomic analysis revealed greater bacterial diversity during the Southwest Monsoon, dominated by Firmicutes and Pseudomonadota, including potentially pathogenic genera such as Staphylococcus, Bacillus and Burkholderia. In contrast, Bacillusand Clostridium predominated during Inter-monsoon II. These findings highlight seasonal variations in airborne bacterial communities and emphasize the need to incorporate microbial assessment into air quality monitoring frameworks.
Genetic Diversity of Pineapple (Ananas comosus) Accessions Using ISSR Markers
Pineapple is a member of Bromeliaceae family and a major tropical fruit crop with significant economic and nutritional importance globally. It contains high levels of vitamin C, sufficient to meet daily human requirements, making it is a highly nutritious fruit commonly consumed worldwide. However, the genetic diversity of pineapple accessions is not well-documented, hampering efforts to improve the crop through breeding programmes. Inter simple sequence repeat (ISSR) markers were used to assess the genetic diversity of 22 pineapple accessions obtained from MARDI Pontian. Five ISSR primers (IS21, IS34/1, UBC 822, UBC 824, UBC 827) amplified a total of 27 bands, of which 22 (81.5%) were polymorphic, with a mean Polymorphism Information Content of 1.236. ISSR primer IS21 and UBC 824 exhibited 100% polymorphism, whereas UBC 822 showed 60%. Jaccard’s similarity coefficient ranged from 0.333 to 0.850, indicating extremely high genetic diversity among pineapple accessions. Cluster analysis was conducted using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) to generate a dendrogram in NTSYS-pc software. The dendrogram based on UPGMA analysis grouped the 22 pineapple accessions into two main clusters. Cluster I comprised 21 accessions subdivided into two smaller clusters, whereas Cluster II contained a single accession. This study provides valuable data for utilizing genetic diversity in pineapple breeding and estimating heterosis. ISSR analysis proved to be an efficient method for assessing genetic variation, supporting both germplasm conservation, and breeding improvements.
Unravelling Microbial Communities in the Rhizosphere Soil of Selected Dipterocarpaceae species through Amplicon Sequencing
The Dipterocarpaceae family, comprising nearly 700 species, is a dominant component of Southeast Asian tropical rainforest. In Malaysia, dipterocarps are widely distributed and serve as one of the essential tree families in the forest ecosystems. Their rhizosphere represents a unique microhabitat where complex interactions between roots, soils, and microbial communities occur. However, there are limited datasets on microbial diversity of Malaysian dipterocarp rhizosphere soil. This study aimed to unravel the microbial diversity of selected dipterocarp species (Dipterocarpus oblongifolius, Neobalanocarpus heimii, Shorea sumatrana, and Dryobalanops aromatica) across three environmentally different sites: the FRIM Dipterocarp Arboretum, Valencia (township), and Wetland Arboretum Centre (WAC) (nursery), using amplicon sequencing. Bacterial communities were dominated by Proteobacteria across all sites, with WAC showing significantly higher bacterial diversity (Shannon index). Eukaryotic communities were primarily fungal, dominated by Basidiomycota and Ascomycota, with WAC showing significantly higher eukaryotic diversity (Shannon index). Beta diversity analysis revealed distinct clustering patterns, with WAC harboring the most unique community structures for both bacteria and eukaryotes. This study reveals that site-specific conditions drive the microbial diversity and composition of dipterocarp rhizosphere soil.
Isolation and Characterisation of High Value Microbes from Rhizosphere Soil of Dipterocapaceae Plants
The rhizosphere soil of Dipterocapacea supports diverse microbial communities with functional potentials relevant to forest conservation, agriculture and environmental sustainability. This study investigated the microbial functional capabilities of rhizosphere soil from four selected dipterocarp species (Dipterocarpus oblongifolius, Neobalanocarpus heimii, Shorea sumatrana and Dryobalanops aromatica) from FRIM Dipterocarp Arboretum, Gamuda Valencia (Township) and Wetland Arboretum Centre (WAC) (Nursery). Culture-dependent approaches successfully isolated diverse functional isolates. 62 cellulose-degrading bacteria were isolated using three selective media, with carboxymethyl cellulose (CMC) agar proving most effective (28 isolates). Four Actinomycetes isolates displaying characteristics of filamentous morphology and pigments diffusion were recovered, with Actinomycetes Isolation Agar (AIA) yielding optimal results. Plant growth-promoting bacteria (PGPB) demonstrated significant capabilities in indole-3-acetic acid synthesis, phosphate solubilization and zinc solubilization, with combined PGPB-fertiliser treatments producing better growth outcomes for Brassica juncea seedlings. Heavy metal resistance screening identified 20 bacterial isolates capable of tolerating elevated concentrations of Ni (4000 mg/L), Pb (1500 mg/L), Cr (1500 mg/L), Cd (550 mg/L) and As (600 mg/L). These findings demonstrate the rich functional diversity of dipterocarp rhizosphere soil microbiomes and their potential for sustainable agriculture, bioremediation and pharmaceutical applications.
Taburan Flora pada Mikrohabitat Berbeza di Bukit Gua Madu, Kelantan
Kajian telah dijalankan di Bukit Gua Madu, Kampung Batu Papan, Kelantan. Ia adalah kawasan rekreasi bagi penduduk setempat dan juga pengunjung luar kawasan. Bukit ini dikelaskan sebagai hutan jenis batu kapur dan terletak di pantai timur Semenanjung Malaysia. Persampelan telah dilakukan di beberapa kawasan geomorfologi bukit batu kapur seperti longgokan jatuhan batu, tebing curam, gua dan binaan gua, lembah, dataran aluvium dan puncak. Objektif kajian ini adalah untuk mendokumentasikan kepelbagaian flora mengikut mikrohabitat berbeza di kawasan batu kapur. Plot berukuran 5 m x 5 m (25 m2) dibina di mikrohabitat yang terdapat pada setiap pembentukan geomorfologi bukit. Pemerhatian mikrohabitat dan spesies tumbuhan telah direkodkan. Spesies Streblus ilicifolius, Saraca thaipingensis, Anaxagorea javanica dan Peliosanthes teta var. teta mudah dijumpai di dataran aluvium. Microchirita caliginosa dan Begonia nurii di dinding gua, Gnetum sp. dan Chloranthus sp. di lereng bukit, serta Cycas sp. dan Pandanus irregularis di puncak. Selain itu, Impatiens foxworthyi dan Begonia kingiana direkodkan di atas permukaan batu yang merekah, Epithema sp. pada bongkah batu, manakala Aglaonema sp. di kawasan lembah. Hasil kajian mendapati setiap mikrohabitat batu kapur mempunyai taburan flora yang berlainan, sekali gus memperlihatkan kepentingannya sebagai habitat khusus yang wajar diberi perhatian dalam usaha pemeliharaan kepelbagaian biologi.
Komposisi Flora Hutan Batu Kapur Pada Mikrohabitat di Bukit Kurau, Perak dan Gua Ikan, Kelantan
Hutan batu kapur merupakan salah satu jenis hutan yang terdapat di Semenanjung Malaysia. Kajian komposisi flora pada mikrohabitat berbeza telah berjaya dijalankan di Bukit Kurau, Perak dan Gua Ikan, Kelantan. Pensampelan flora dijalankan pada geomorfologi hutan batu kapur yang memiliki ciri mikrohabitat seperti puncak, lembah, tebing curam, permukaan gua, longgokan jatuhan batu dan dataran aluvium. Plot berukuran 5 m x 5 m telah ditubuhkan pada setiap mikrohabitat berbeza. Sejumlah 187 sampel tumbuhan telah direkodkan di Bukit Kurau manakala, 141 individu direkodkan di Gua Ikan. Spesies Amischotolype griffithii direkodkan dominan di dataran aluvium, Microchirita caliginosa, Monophyllaea hirticalyx dan Monophyllaea horsfieldii di permukaan gua manakala, Begonia kingiana, Hoya coronaria dan Rhynchoglossum obliquum di tebing curam. Bagi longgokan jatuhan batu, spesies yang mendominasi kawasan tersebut ialah Peliosanthes teta var. teta manakala, di lembah terdapat Impatiens glaricola, Alocasia farisii dan Hapaline brownii yang mendominasi kawasan ini. Hasil kajian bagi dua lokasi ini membuktikan komposisi flora amat berbeza pada mikrohabitat hutan batu kapur.
Protokol Pensterilan Optimum Thuidium cymbifolium dan Thuidium pristocalyx var. samoanum: Lumut berkualiti tinggi
Lumut memainkan peranan ekologi kritikal dalam penyerapan air, pengurangan hakisan tanah dan pengawalan banjir serta berfungsi sebagai bioindikator sensitif terhadap perubahan kualiti udara dan air di persekitaran. Namun, permintaan pasaran yang meningkat dalam industri hortikultur terutamanya dalam penghasilan terarium, berpotensi mengancam kelestarian spesies ini memandangkan kadar pertumbuhan semula yang perlahan di habitat asal. Kultur in vitro muncul sebagai strategi efektif bagi pemeliharaan biodiversiti di samping membolehkan pengeluaran lumut pada skala yang besar dalam tempoh singkat tanpa eksploitasi berlebihan sumber semula jadi. Kajian ini memberi tumpuan kepada pengoptimuman protokol pensterilan permukaan eksplan bagi Thuidium cymbifolium (Dozy & Molk.) Dozy & Molk. dan Thuidium pristocalyx var. samoanum (Mitt.) Touw memandangkan kontaminasi merupakan faktor penghalang utama yang sering terjadi dalam kejayaan kultur in vitro. Hasil menunjukkan bahawa protokol optimum bagi T. cymbifolium adalah menggunakan 80% etanol (EtOH) selama 30 saat diikuti 5% sodium hipoklorit (NaOCl) selama 80 saat, manakala bagi T. pristocalyx var. samoanum adalah menggunakan 80% EtOH selama 30 saat diikuti 5% NaOCl selama 120 saat. Kedua-dua protokol pensterilan ini berjaya menghasilkan 100% kultur bersih tanpa kontaminasi selepas 30 hari pengkulturan. Penemuan ini membuktikan bahawa protokol pensterilan yang berbeza diperlukan antara spesies, berkemungkinan disebabkan oleh fungsi lumut sebagai mikrohabitat kepada pelbagai invertebrata yang mana meningkatkan risiko kontaminasi. Selain itu, protokol sterilasi yang optimum ini juga digunakan dalam pengaruhan pucuk dan akar eksplan, seterusnya membuka peluang kepada pembiakan berskala besar. Secara keseluruhan, hasil kajian ini menyumbang kepada pemuliharaan ex-situ serta menawarkan asas saintifik yang kukuh untuk menyokong komersialisasi lestari Thuidiaceae tanpa menjejaskan populasi liar.
Lumut Jati Sebagai Bioindikator Pemendapan Logam Berat di Sekitar Stesen Janakuasa Elektrik Sultan Salahuddin Abdul Aziz, Kapar, Klang, Selangor
Stesen Janakuasa Elektrik berasaskan arang batu merupakan antara penyumbang utama peningkatan indeks pencemaran udara, yang memberi kesan buruk kepada manusia dan ekosistem. Namun, peralatan konvensional sedia ada memerlukan kepakaran tinggi serta kos yang mahal. Justeru, kajian ini dijalankan untuk menilai potensi lumut jati sebagai bioindikator dalam pemantauan pencemaran logam berat di kawasan perindustrian. Ini kerana lumut jati berupaya menyerap logam berat daripada atmosfera melalui permukaan yang luas dan mempunyai kadar metabolisme yang rendah. Lokasi pensampelan adalah di sekitar Stesen Janakuasa Elektrik Sultan Salahuddin Abdul Aziz, Kapar, Klang, Selangor (kawasan tercemar), manakala Bukit Fraser, Pahang dipilih sebagai lokasi kawalan (kurang tercemar). Sampel lumut jati dikutip, dikeringkan dan diayak dengan penapis 100 µm, kemudian diproses menjadi pelet menggunakan asid borik sebelum dianalisis melalui kaedah Sinar-X Pendarfluor (XRF). Enam unsur logam berat yang dianalisis ialah natrium (Na), ferum (Fe), kuprum (Cu), kalium (K), zink (Zn) dan mangan (Mn). Data kepekatan logam berat dibandingkan menggunakan Ujian-t Sampel Tidak Bersandar untuk menentukan perbezaan signifikan, manakala ANOVA sehala digunakan untuk menilai sama ada jarak dari sumber pencemaran memberi kesan terhadap kepekatan logam dalam sampel. Hasil menunjukkan tiada perbezaan signifikan (p > 0.05) antara kepekatan logam berat di Klang dan Bukit Fraser. ANOVA juga menunjukkan jarak dari sumber pencemaran tidak mempengaruhi taburan logam dalam lumut jati. Namun, sisihan piawai besar dan variasi lokasi ketara menunjukkan faktor persekitaran seperti kelembapan, kedudukan berhampiran sistem saliran dan variasi spesies boleh mempengaruhi corak bioakumulasi. Oleh itu, penggunaan lumut jati sesuai dijadikan sebagai bioindikator pencemaran logam berat secara saintifik dan mampan. Coal-fired power stations are among the main contributors to the increase in air pollution indices, which have adverse effects on humans and ecosystems. However, existing conventional equipment requires high expertise and is expensive. Therefore, this study was conducted to evaluate the potential of moss as a bioindicator in monitoring heavy metal pollution in industrial areas. This is because moss is able to absorb heavy metals from the atmosphere through a large surface area and has a low metabolic rate. The sampling location was around the Sultan Salahuddin Abdul Aziz Power Station, Kapar, Klang, Selangor (polluted area), while Bukit Fraser, Pahang was chosen as the control location (less polluted). Moss samples were collected, dried and sieved with a 100 µm filter, then processed into pellets using boric acid before being analyzed using the X-ray Fluorescence (XRF) method. The six heavy metal elements analyzed were sodium (Na), iron (Fe), copper (Cu), potassium (K), zinc (Zn) and manganese (Mn). Heavy metal concentration data were compared using Unpaired Samples t-Test to determine significant differences, while one-way ANOVA was used to assess whether distance from the pollution source affected the metal concentration in the sample. The results showed that there was no significant difference (p > 0.05) between heavy metal concentrations in Klang and Bukit Fraser. ANOVA also showed that distance from the pollution source did not affect the distribution of metals in moss. However, the large standard deviation and significant location variation indicate that environmental factors such as humidity, proximity to drainage systems and species variation can affect the bioaccumulation pattern. Therefore, the use of moss is suitable as a bioindicator of heavy metal pollution in a scientific and sustainable manner.
Bacteriocin-like inhibitory Substance (BLIS) Produced by Lactococcus lactis strain FA4 with Potential for Use in Aquaculture
Lactococcus lactis is a lactic acid bacteria isolated from dairy environment which is considered as generally regarded as safe (GRAS). A L. lactis strain FA4 was previously isolated from Black tip shark have shown antagonistic properties against Vibrio parahaemolyticus, a shrimp and fish pathogen. In this study, cell free supernatant (CFS) from L. lactis FA4 has shown active antagonism against the growth of indicator strain V. parahaemolyticus, but not against V. alginolyticus. With V. parahaemolyticus, the minimum inhibitory concentration (MIC) recorded around 0.125AU/ml. The CFS component was found to be rather stable during brief heat treatment, retaining ~86% of residual activity, and alkaline treatment had retained ~60.8% of residual activity. SDS page analysis and zymogram studies revealed that the CFS contains proteinaceous substance that have molecular weight of approximately ~3-5kDa. Based on several previous studies, L. lactis strain FA4 produces a bacteriocin like substance (BLIS) that highly resembles to that of nisin. Therefore, the BLIS has future potential to be utilized as antimicrobial agent suitable to be used in aquaculture treatment.
Population Census and Ranging Pattern of The Long-Tailed Macaques (Macaca fascicularis) at Human-Altered Environment
The Universiti Kebangsaan Malaysia (UKM), Bangi campus is located within the natural habitat of the long-tailed macaque (Macaca fascicularis). Its proximity to surrounding forested areas has resulted in a high degree of habituation among the macaques toward human presence. However, data on their population size and ranging patterns remain limited. This study aimed to determine the population size and ranging areas of habituated long-tailed macaques within the UKM main campus. Systematic field surveys were conducted from October 2021 to October 2022, involving group identification, population census, and GPS-based location mapping. Ranging areas were calculated using the Minimum Convex Polygon (MCP) and 95% Kernel Density Estimation (KDE) methods. Core areas and disturbance zones were further delineated for each identified group. A total of 10 macaque groups comprising 581 individuals were recorded across the campus. Based on 965 GPS location points, the groups’ areas ranged from 7.99 ha to 39.54 ha (mean ± SD: 19.30 ± 8.85 to 23.52± 12.45 ha). Twelve overlapping zones were detected, seven identified as core areas shared among multiple groups. These findings provide updated insights into the population dynamics and spatial ecology of long-tailed macaques at UKM. The information obtained serves as a critical reference for developing effective management and mitigation strategies to reduce human–macaque conflicts within the campus environment.
Corak Aktiviti Temporal Mamalia di Landskap Ladang Sawit Berbeza di Semenanjung Malaysia
Penanaman kelapa sawit di Semenanjung Malaysia telah mengubah mozek hutan–pertanian, sekali gus menimbulkan persoalan tentang cara mamalia menyesuaikan corak aktiviti harian mereka dalam landskap yang didominasi manusia. Kajian ini menggunakan perangkap kamera bagi menilai aktiviti diel dan pertindihan temporal (Δ) mamalia terrestrial, merentasi tiga jenis guna tanah iaitu ladang monokultur, ladang dengan tompok hutan, dan ladang bersebelahan hutan. Sebanyak 2,567 pengesanan bebas diperoleh meliputi 28 spesies. Analisis temporal terhadap 11 taksa tumpuan menunjukkan bahawa spesies nokturnal tegar (contohnya, Malayan civet; ≥0.70) mengekalkan rutin yang sama tanpa mengira konteks landskap. Sebaliknya, spesies umum diurnal (contohnya kera ekor panjang, long-tailed macaque) mempamerkan keanjalan tingkah laku dengan mengubah tempoh aktif berdasarkan jarak kepada hutan. Analisis pertindihan dengan kehadiran manusia menunjukkan kecerunan toleransi yang jelas. Spesies umum (beruk, babi hutan, kijang) menunjukkan persamaan temporal yang tinggi (Δ≥0.60) dengan aktiviti antropogenik pada siang hari, menandakan kewujudan bersama atau penghabituatan. Sebaliknya, karnivor kecil nokturnal dan spesies sensitif (contohnya musang pulut, common palm civet; Δ≤0.27) jelas mengelakkan waktu manusia, dengan mengalih aktiviti sepenuhnya pada waktu malam. Kajian ini merumuskan bahawa gangguan manusia merupakan penapis ekologi utama yang mendorong perubahan temporal dalam taksa mamalia, manakala pengekalan penampan hutan membolehkan penyesuaian tingkah laku serta kewujudan bersama bagi spesies umum.
From Natural to Anthropogenic: Comparative Analysis of House Crow Nesting Strategies in Urban and Rural Penang Environments
The House Crow (Corvus splendens) exhibits exceptional generalist traits that enable its survival across diverse anthropogenic landscapes. Understanding how urbanization influences nesting behavior is crucial for managing this invasive species in Southeast Asia. This study investigates nest composition and identifies key factors influencing nest-site selection across an urbanization gradient in mainland Penang, Malaysia. Two contrasting sites were examined: Seberang Perai Tengah (SPT, urban site) and Seberang Perai Utara (SPU, rural/agricultural site). Forty-seven nests (30 from SPT, 17 from SPU) were systematically collected and analyzed for construction materials. Results revealed dramatic site-specific differences in material selection. Urban nests were dominated by metal wires (52.49% by count, 58.44% by weight), while rural nests primarily utilized natural materials—twigs (46.81% by count) and small branches (41.00% by weight). Both sites demonstrated heavy reliance on anthropogenic resources, with artificial nest materials (waste bins, construction sites, recycling centers, residential areas) more abundant than natural alternatives (95% urban, 73% rural). Nest-site preferences also differed between habitats. Urban crows selected trees with 70-100% canopy cover near food resources (mean distance = 300.35 ± 161.28 m), while rural crows preferred trees 4-9 m tall with canopies <15 m wide near water resources (mean distance = 402.13 ± 233.91 m). These findings highlight the House Crow's remarkable behavioral plasticity in response to urbanization, with nesting strategies shaped by local resource availability and tree architecture, providing insights for urban wildlife management.
Cave-Roosting Bat Ecology in Malaysian Agroecosystems: The Gunung Keriang Study
Malaysia is home to remarkable biodiversity, with bats comprising nearly one-fifth of all mammal species globally. This study investigated the diversity and breeding patterns of bats at Gunung Keriang, which is surrounded by rice field areas. A total of 1,250 individuals representing 22 species were recorded between April 2021 and April 2022, primarily from the families Rhinolophidae, Hipposideridae, and Vespertilionidae. The most abundant species was Rhinolophus pusillus (n=857). Several species face extinction risks based on the IUCN Red List, including Myotis ridleyi (Near Threatened), H. lekaguli (Near Threatened), and H. halophyllus (Vulnerable). Regardless of family, the three studied bat species in Gunung Keriang exhibited a unimodal breeding pattern throughout the year. This indicates that cave-roosting bats reproduce only once annually, with active breeding stages (pregnancy and lactation) concentrated in April and May. Based on species-specific observations, pregnancy was recorded two months later in Myotis ridleyi (April, early dry season) than in Rhinolophus pusillus and Hipposideros larvatus (February, end of wet season). The percentage of non-reproductive Hipposideros larvatus began to increase in August, approximately three months after the first juvenile/pup was recorded. Lactating females of Rhinolophus pusillus were recorded in April, with peak lactation occurring in May. These findings emphasise Gunung Keriang's importance as a vital natural refuge for Malaysia's bat conservation. The breeding pattern of cave-roosting bats in Gunung Keriang showed synchronised maternity with the availability of insects (food resources) in agricultural areas.
Chiropteran Diversity in Teluk Bahang Forest Eco Park: Additional Bat Species Records and Conservation Status
Bats, which serve as crucial biological seed dispersers and pest controllers, have largely lost their main habitat due to human development and deforestation. Rapid population growth has resulted in increasing demand for human settlements and it has become particularly critical for small states, such as Penang. Hence, a study was conducted to update bat species records in Teluk Bahang Forest Eco Park, Penang. A total of 45 individuals were caught, consisting of two families and six species of bats. Compared to previous study, two additional bats species were recorded during this expedition; Hipposideros armiger and Rhinolophus pusillus. Rhinolophus affinis is the highest captured species in this study compared to others. In terms of conservation status, there are differences between global and national categorizations. Rhinolophus pusillus is listed as Least Concern on IUCN Red List however it is classified as Data Deficient (DD) at national level. Meanwhile, Rhinolophus refulgens is listed as Not Evaluated (NE) on the IUCN Red List and listed as Data Deficient (DD) nationally. Additionally, Hipposideros kunzi is categorized as Not Evaluated (NE) on IUCN Red List and Data Deficient (DD) at national level. The increased number of bat species at new localities demonstrates the need to conserve various habitat types in Penang.
Multifunctional PNSB as a Live Feed Enhancer: Improving Artemia Performance and Disease Resistance
The application of Artemia as a live feed in aquaculture is often limited by the high cost and variable quality of commercial cysts. This study explores the potential of two mangrove-associated purple non-sulfur bacteria (PNSB) strains - Rhodopseudomonas palustris AZR1 and Rhodopseudomonas faecalis AZW1 - as probiotic feed supplements to enhance the nutritional and health status of Artemia. The Artemia-fed treatments (AFT) received yeast and Artemia twice daily at 3.0 x 107 cells/mL for 14 days, whereas the PKC Nutri+ treatment was maintained at an OD600 of 0.3. Flavonoid contents in the PNSB strains and Artemia-fed treatments (AFT) were measured by spectrophotometry and HPLC. Nutritional contents were assessed using proximate analysis, and fatty acid contents were quantified via GC-MS. Twenty AFT were challenge with 1 × 10⁸ CFU/mL of Vibrio campbellii and survival were observed after 72hr. Strain characterization revealed that R. palustris AZR1 exhibited superior carotenoid production, with significantly higher astaxanthin (0.324 μg/mL) and β-carotene (0.228 μg/mL) levels compared to R. faecalis AZW1 (0.254 and 0.160 μg/mL, respectively; p < 0.05). Additionally, R. palustris AZR1 showed a significantly greater total lipid content (7.77%) than R. faecalis AZW1 (6.76%; p < 0.05), despite overall comparable nutritional profiles. When used as a live feed, R. palustris AZR1 significantly enhanced Artemia growth, with differences becoming statistically significant from Day 4 onward (p < 0.05). Under gnotobiotic conditions, Artemia fed R. palustris AZR1 reached a mean length of 9.6 ± 0.32 mm by Day 14, outperforming those fed PKC Nutri+ (7.6 ± 0.43 mm) and yeast (7.5 ± 0.25 mm). A similar growth advantage was observed under hatchery conditions, where R. palustris AZR1-fed Artemia attained the highest length (10.1 ± 0.08 mm), surpassing both PKC Nutri+ (9.7 ± 0.55 mm) and yeast (8.5 ± 0.36 mm). Moreover, Artemia supplemented with R. palustris AZR1 demonstrated enhanced resistance to Vibrio campbellii challenge, which correlated with the upregulation of key immune-related genes, including Hsp70, Hsp90, and proPO. Nutritional analysis confirmed effective transfer of beneficial biomolecules, including carotenoids and lipids, from the PNSB to Artemia. While PKC Nutri+ was richer in polyunsaturated fatty acids (PUFAs), R. palustris AZR1 offers a safer, toxin-free alternative. In conclusion, this study highlights the potential of the mangrove-derived R. palustris AZR1 as a sustainable, multifunctional single-cell protein source with strong probiotic properties, capable of improving Artemia growth, immune competence, and nutritional quality in aquaculture systems.
Species Composition and Diversity of Birds for Potential Environmental and Biological Sensitive Areas in Langkawi, Kedah
Langkawi which was recognised in 2007 as Southeast Asia’s first UNESCO Global Geopark for its exceptional Palaeozoic geological record, is also a major tourist destination in Malaysia. Rapid coastal development for tourism, however, is altering critical habitats for coastal birds. To address the absence of baseline data, this study conducted a comprehensive, three-day survey of coastal bird populations across Langkawi. Bird observations and photographic documentation were conducted during peak activity periods (morning and evening), recording 1,055 individuals from 66 species in 30 families. Ardeidae was the most species-rich family (eight species), while the Brahminy Kite (Haliastur indus) was the most abundant (149 sightings). The survey documented two threatened species on the IUCN Red List namely the Great Hornbill (Buceros bicornis) and the near threatened Brown-winged Kingfisher (Pelargopsis amauroptera). Overall, coastal bird biodiversity was high (Shannon Index, H'=3.45; Simpson Index, 1-D=0.95). The western coastal area near Cenang exhibited the highest diversity (H'=3.27, 44 species), followed by the northern region encompassing Tanjung Rhu and Kilim Karst Geoforest Park (H'=3.24, 34 species). These results underscore Langkawi’s important role as a habitat for coastal and threatened birds and provide a crucial baseline for identifying Environmental and Biological Sensitive Areas (EBSAs) and may contribute toward sustainable coastal management strategies.
Revealing the Bacterial Community Structure of Aerobic Granular Sludge for Agro-based Wastewater Treatment
This study examined the development and composition of bacterial communities in an aerobic granular sludge bioreactor using Illumina high-throughput sequencing. Mature granules with a compact structure were obtained after 90 days of bioreactor operation, with the organic loading rate varying between 2.5 and 3.3 kg COD m-3 d-1. Cocci-shaped microbes were observed to cover the outer surface of granules. Reliable COD and simultaneous nitrogen and phosphorus removal efficiencies were achieved during the steady-state period. Metagenomic sequencing analysis revealed that Pseudomonas (34.05%) was the most dominant genus, followed by Bacteroides (10.27%) and Clostridium (2.68%). Several microorganisms were identified as functional bacterial groups responsible for pollutant removal, contributing to organic and nutrients biodegradation. Exopolysaccharide-producing bacteria, accounting for 70.71% of the total abundance, appeared to be responsible for the formation of granules, and the stability of the microbial granulation reactor.
Epicuticular Wax Content on Leaf Epidermis of Selected Brassica L. Taxa in Relation to Feeding Behaviour Against Diamondback Moth, Plutella xylostella L. (Lepidoptera: Plutellidae) Larvae
Many aspects of epicuticular waxes have been studied over the years. In plants, the epicuticular wax layer provides a protective barrier, which consists predominantly of long-chain hydrocarbon compounds, including alkanes, primary alcohols, aldehydes, secondary alcohols, ketones, esters, and other derived compounds. However, there is a limited understanding of the relationship between animal or insect-eating habits and plant micromorphological characteristics. This study investigated the impact of epicuticular wax content in five selected taxa of Brassica L. on the feeding behaviour of diamondback moth (DBM), Plutella xylostella L., using observation under the scanning electron microscope (SEM). The findings have revealed that the epicuticular waxes' morphology content was composed primarily of rodlets, flakes, thread-like, granular, and smooth film coating. The analysis was conducted using a one-way analysis of variance (ANOVA). Findings have shown that there was a significant difference regarding the time spent on feeding by the larvae of the 3rd instar of the DBM both in choice (F = 510.58, df = 5 & 54, P < 0.05) and no-choice tests (F = 38.92, df = 5 & 54, P < 0.05) to the epicuticular wax content in Brassica leaves. These insect pests showed a weak preference for leaves with high epicuticular wax. It was concluded that the variation in waxes present in the Brassica taxa studied has great significance as a mechanical barrier to the DBM larvae.
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