Bioresources and Environment

Sustainable Bioproduction of Xanthan Gum by Xanthomonas campestris Using Fructose and Black Soldier Fly Larvae as a Novel Nitrogen Source

Muhammad Safiy Hafiz Sharif — 2025-10-28

Xanthan gum is a microbial exopolysaccharide produced commercially through the fermentation of Xanthomonas campestris using carbon sources. It is widely used in industries such as food, medicine, textile, and oil due to its properties as a stabilizer, thickener, and emulsifier. However, the high cost of xanthan production and its environmental impact, particularly when relying on traditional carbon sources like glucose, pose significant challenges. This study explores the use of agricultural waste as a cost-effective carbon source and investigates the potential of Black Soldier Fly Larvae (BSFL) as an alternative nitrogen source for xanthan production. Xanthomonas campestris ATCC 13951 was cultivated in media containing fructose (40 g/L) as the carbon source and varying concentrations of BSFL (2, 4, 6, 8, and 10 g/L) as the nitrogen source. The results demonstrated that the medium containing 2 g/L of BSFL yielded the highest xanthan production at 5.29 g/L, indicating the potential of BSFL as a sustainable nitrogen source for xanthan synthesis. This study highlights the feasibility of using alternative, low-cost substrates to improve the economic and environmental sustainability of xanthan production.

A Preliminary Review on the Morphological and Phytochemical Characteristics of Rambutan (Nephelium lappaceum L.)

Liliwirianis Nawi — 2025-10-28

Rambutan (Nephelium lappaceum L.), a member of the family Sapindaceae, is a tropical fruit species native to Southeast Asia and recognised for its nutritional and medicinal potential. This preliminary review aims to summarise the basic morphological characteristics of N. lappaceum, including its leaves, flowers, and fruits. Besides compiling available information on its phytochemical composition and biological activities. A systematic literature search was conducted using books and databases such as Scopus, PubMed, and ScienceDirect, applying defined inclusion and exclusion criteria. The findings show clear morphological differences among the plants, highlighting the need for more detailed comparisons and consistent taxonomic descriptions. Taxonomic uncertainties also persist due to overlapping morphological traits and limited molecular phylogenetic data. Although phytochemical studies have shown strong antioxidant, antimicrobial, and anti-inflammatory effects, standardized testing and in vivo verification are still limited. This preliminary synthesis provides a foundational reference for future, in-depth studies on the taxonomy, morphology, and pharmacological potential of N. lappaceum.

Assessment of Surface Finishing Quality of Kelempayan (Neolamarckia cadamba) Wood for Furniture Components

Nur Hannani Abdul Latif — 2025-10-28

Kelempayan (Neolamarckia cadamba) is a fast-growing plantation species with increasing potential for Malaysia’s furniture sector. Despite its advantages of rapid growth and light colour, its relatively may challenge finishing processes, especially in achieving high-quality coated surfaces due to low density and coarse texture. This study examines the influence of different abrasive papers and finishing systems on the surface quality of Kelempayan wood (Neolamarckia cadamba). The sawn timbers were conventionally kiln dried to 12% moisture content before being cut to end size. Then, the samples were sanded using two different types of abrasive papers which are silicon carbide and aluminum oxide. Two finishing systems were then applied which involved System 1 (applying a single coat of varnish following sanding) and System 2 (two cycles of sanding and varnishing). After that, three types of finishing testing were conducted to assess the surface finishing quality of the samples. The finishing tests were the pencil hardness test, adhesion tape (cross-cut test) and surface roughness test. Sixty samples in all were prepared and tested. The results indicated that both abrasive paper and the finishing system variables highly influenced the surface quality of samples. The application of aluminum oxide paper resulted in better performance of pencil hardness and surface roughness tests than those sanded with silicon carbide. Finishing System 2 also provided a similar pattern of results, which improved the toughness, and the surface roughness was reduced to 0.38 μm compared to System 1. In the cross-cut adhesion test, both variables provided good coat adhesion, with less than 5% to no flaking. Overall, it can be concluded that the combination of aluminum oxide abrasive paper and multicoat finishing can greatly improve the durability and surface appearance of Kelempayan for furniture components.

Eco-Friendly Synthesis of Iron Oxide Nanoparticles Using Mulberry Leaves Extract for Heavy Metal Removal from Water

Nur Shafieza Azizan — 2025-10-28

Various natural and anthropogenic factors, including inadequate water treatment, urbanisation, industrialisation, and the intensification of agricultural output, can result in the presence of heavy metals in water, the atmosphere, and sediments. Heavy metal pollution poses a severe threat to aquatic ecosystems and human health due to its persistence, bioaccumulation, and toxicity. Zinc ions (Zn²⁺), though essential in trace amounts, becomes hazardous at elevated concentrations. This study reports the green synthesis of magnetite iron oxide nanoparticles (Fe₃O₄-NPs) using mulberry leaf (Morus alba) extract as a natural reducing and stabilizing agent. The nanoparticles were tested for Zn²⁺removal efficiency under varying conditions of initial concentration (0.5–3.0 mg/L), pH (4–9), contact time (15–90 min), and adsorbent dosage (0.4–1.4 g). Optimal conditions were observed at 1.0 mg/L Zn²⁺, pH 9, 75 minutes contact time, and 1.0 g adsorbent dosage, achieving a removal efficiency of 98%. Adsorption data fitted well to the Langmuir isotherm (R² = 0.86), indicating monolayer adsorption on a homogeneous surface, while kinetics followed the pseudo-second-order model (R² = 0.95), suggesting chemisorption. These findings highlight the potential of mulberry leaf-derived Fe₃O₄-NPs as an eco-friendly, cost-effective adsorbent for heavy metal remediation, supporting sustainable water treatment strategies.

Maximising pitaya (Hylocereus polyrhizus) peel pectin yield through cellulase-assisted extraction: A study on enzyme optimisation

Majida Al-Ezzi — 2025-10-28

Red-purple pitaya (Hylocereus polyrhizus) peel is a rich source of plant pigment betacyanins and dietary fibre specifically pectin. Pectin's multifunctional properties enable its use in the healthcare industry. This study investigated the optimum conditions for cellulase enzyme to release maximum pectin from pitaya peel puree. Parameters such as cellulase concentration (50 - 300 μL/100 g of puree), pH (3 - 5.4), time (30 - 180 min) and temperature (25 - 50 °C) were varied for cellulase optimisation followed by pectin extraction using water extraction method and pectin yield determination. The optimal conditions for maximising pectin extraction from pitaya peel were a cellulase concentration of 100 μL per 100 g of puree, a pH of 5.40, a temperature of 37 °C, and a pre-treatment time of 120 minutes. At these optimum conditions for pre-treatment of puree with cellulase, 22.30% of pectin was extracted from pitaya peel pectin using distilled water at pectin extraction conditions reported in our previous study (temperature: 73 °C, time: 67 min, sample to solvent ratio: 1:4). When extraction was performed using varying concentrations of citric acid (0.5 - 2.0%) solutions, a maximum pectin yield (24.63%) at 1.5% citric acid concentration was noted. Based on the proximate composition, functional groups and degree of esterification findings, cellulase-assisted extraction demonstrates strong potential to convert fruit peels into valuable pectin.

Informal Land Delivery System and Access to Land for Urban Agriculture in Ilorin, Nigeria

Ola Akeem Bayonle — 2025-10-28

Most studies on land delivery systems have focused on the role of informal mechanisms in facilitating residential land access, while their influence on agricultural land delivery has received limited attention. This study examines the role of informal land agents in supporting urban agriculture in Ilorin, Nigeria. Using a cross-sectional survey design, primary data were collected through structured questionnaires administered to 73 randomly selected informal land agents and 303 urban farmers across the three Local Government Areas of Ilorin. Data was analysed using descriptive statistics and inferential techniques, including the Respondents’ Agreement Index (RAI) and Pearson correlation analysis. Results revealed that most informal agents were male, aged between 20 and 39 years. Land was mainly acquired through direct contact with owners (72.6%), and location was the primary factor determining price (78.2%). Informal agents serve as key intermediaries in supplying land for urban agriculture, bridging gaps in the formal land administration system. A strong positive correlation was found between the existence of informal land delivery systems and access to agricultural land. The study recommends formal recognition of these agents and regular training on urban land use priorities.

Comparative Corrosion Behaviour of Mild Steel and Stainless Steel in Hydrochloric and Nitric Acid Environments: Implications for Sustainable Material Use

Muhammad Syakir Zukfli — 2025-10-28

Corrosion of structural metals in acidic environments remains a critical concern for both industrial efficiency and environmental sustainability. This study comparatively investigates the corrosion behaviour of mild steel and stainless steel in hydrochloric acid (HCl) and nitric acid (HNO₃) media at varying concentrations and immersion periods. Weight loss measurements were used to evaluate corrosion rates, supported by comparative analysis over a five-day exposure. The results revealed that corrosion rates increased with acid concentration and exposure time where HNO₃ showing stronger corrosive aggressiveness than HCl due to its oxidizing properties. Mild steel experienced significantly higher mass loss than stainless steel due to the absence of a stable passive oxide layer. A gradual reduction in corrosion rate after prolonged exposure indicated the formation of protective corrosion products that limit further dissolution. Overall, stainless steel demonstrated superior corrosion resistance under all conditions. These findings are vital for material selection in chemical and process industries, particularly where equipment is exposed to acidic effluents. Minimizing corrosion-related failures not only extends the service life of metallic components but also reduces environmental contamination and conserves metallic bioresources through more sustainable industrial practices.

A Preliminary Study on Floristic Composition of Trees in Pelangai Forest Reserve, Kuala Pilah, Negeri Sembilan

Ahmad Fitri Zohari — 2025-10-28

A preliminary study was conducted to determine the floristic composition and community structure of trees in Pelangai Forest Reserve, Kuala Pilah, Negeri Sembilan. Two temporary ecological plots with the dimension of 25 m x 20 m (0.1 ha in total) had been established. The census was carried out for all trees with a diameter at breast height (DBH) of 5.0 cm and above. The floristic composition consisted of 135 individuals from 78 species, 67 genera, and 28 families. The most speciose family was Dipterocarpaceae with eight species, followed by Fabaceae with seven species. The main canopy and understorey species groups recorded the highest number of species and individuals, with 28 and 22 species and 51 and 44 individuals, respectively. Pentace strychnoidea represented the highest total number of individuals for DBH classes of ≥ 5.0 cm, ≥ 10.0 cm and ≥ 15.0 cm. This preliminary study contributed the additional data for logged-over forests in Negeri Sembilan. A detailed study needs to be carried out in the future to obtain more information on tree species in this forest with a large-sized plot and lower measurement of diameter.

Species Composition of Saplings in Pelangai Forest Reserve, Kuala Pilah, Negeri Sembilan

Ahmad Fitri Zohari — 2025-10-28

A study on the species composition and diversity of saplings (diameter at breast height ≥ 1.0–4.9 cm) was conducted in a regenerating lowland dipterocarp forest at Pelangai Forest Reserve, Kuala Pilah, Negeri Sembilan. The aim of this preliminary study is to know how good the regeneration process is in this forest, as no research has ever been conducted in this forest, either for big trees or saplings. Four quadrats of 5 m x 5 m (0.01 ha) were established in the big tree plot (25 m x 20 m). The floristic composition of saplings was represented by 48 individuals consisting of 34 species, 30 genera, and 20 families. Phyllanthaceae was the largest family in terms of the number of species, with five taxa. Diospyros has recorded the highest total number of species with three taxa. Only one endemic species to Peninsular Malaysia was recorded, namely Diospyros singaporensis. The total basal area for all trees was 3.03 m²/ha. At the family level, Ebenaceae contributed the highest basal area of 0.67 m²/ha, and at the species level, Diospyros singaporensis (Ebenaceae) contributed the highest basal area of 0.53 m²/ha (17.37%). Sapling density in the study plot was 4,800 individuals/ha, with Ebenaceae the densest family, with 900 ind/ha, while Diospyros singaporensis (Ebenaceae) represents the densest species, with 700 individuals per hectare. Despite the time constraints and the establishment of relatively small quadrats, this study provided preliminary data on the floristic composition and abundance of saplings in the remaining regenerating lowland dipterocarp forest in Negeri Sembilan. At present, the biodiversity of the flora is still preserved, as the forest was handed to UiTM and is free from any development.

From pots to soil-a first verified record of outdoor Leucocoprinus birnbaumii (Corda) Singer in Pahang, Malaysia

Amir Malik Halit — 2025-10-28

Leucocoprinus birnbaumii, commonly known as the Flowerpot Parasol, is a saprophytic fungus that typically grows in pots and greenhouses. Although this striking yellow species is cosmopolitan, it is uncommon to encounter the species in soil or in non-cultivated environments. In Malaysia, the outdoor occurrence of this species is recorded from unverified citizen science observations. But many of these public observations are based on immature fruiting bodies, which are easily confused with other yellow fungal species and carry a possible risk of misidentification. This study provides the first verified record of outdoor L. birnbaumii fruiting in the soil, a habitat rarely reported for the species. Although it expands the knowledge of its ecological range, its absence in the current survey suggests that the species does prefer humus rich and composted soil in plant pots rather than open ground. Detailed macro- and micromorphological characteristics of the species are also presented to provide reliable reference material for citizen scientists and emphasizes the importance of specimen-based documentation in fungal biodiversity studies. Species monitoring and conservation strategies are also highlighted to ensure this attractive fungal species is protected against extinction risk.

Species composition and diversity of understorey vegetation at Pelagat Forest Reserve, Besut, Terengganu, Peninsular Malaysia

Nik Hazlan Nik Hashim — 2025-10-28

This study was conducted to determine the species composition and diversity of understorey vegetation in the Pelagat Forest Reserve, Besut, Terengganu. A total of 10 quadrats, each measuring 2 m × 2 m (0.004 ha), were established to assess seedlings with heights ≥ 15 cm up to 1.5 m, and quadrats of 5 m × 5 m (0.025 ha) were set up to assess saplings with a diameter at breast height (DBH) < 5 cm but with a height ≥ 1.5 m. The results showed that a total of 116 individual trees were identified, consisting of 49 individuals belonging to 20 families, 29 genera, and 33 species for the seedling category, while 67 individuals comprising 26 families, 43 genera, and 51 species were recorded for the sapling category. The total density of seedlings and saplings was 12,225 individuals/ha and 2,680 individuals/ha, respectively, with Myrsinaceae contributing the highest seedling family density at 2,250 individuals/ha, while Rubiaceae contributed the highest sapling family density at 440 individuals/ha. At the species level, Ardisia sp. 1 recorded the highest seedling density with 1,750 individuals/ha, while Pentace curtisii, Rubroshorea ovalis, and Saprosma glomerulata were the highest contributors to sapling density, with 120 individuals/ha each. The Shannon Index (H) values were 3.30 and 3.85 for seedlings and saplings, respectively, while the Shannon Evenness Index (E) values were 0.94 and 0.98 for seedlings and saplings, respectively. The Margalef Richness Index (D_MG) values were 8.22 and 11.89 for seedlings and saplings, respectively. A total of eight species endemic to Peninsular Malaysia were recorded in this study, comprising eight families, eight genera, and 10 individuals.