CURRENT APPLIED SCIENCE AND TECHNOLOGY

Activated Carbon-Supported Lipase as Biocatalyst for Biodiesel Synthesis from Crude Palm Oil

Nova Rachmadona — 2025-09-01

Biodiesel is a renewable energy source with significant potential to reduce reliance on fossil fuels. In its production, crude palm oil (CPO) is commonly processed through transesterification, a reaction often catalyzed by lipase enzymes. While these enzymes are effective, their single-use nature results in high production costs. To address this issue, immobilizing lipase enzymes on activated carbon offers a promising solution, enabling the reuse of the enzyme and reducing costs. This study aimed to evaluate the effectiveness of activated carbon as a support for lipase immobilization in biodiesel production from CPO. The immobilization process involved incubating 1 g of activated carbon with 1 mL of lipase and 9 mL of 0.01 M Tris HCl buffer at 30°C for 6 h. The morphology of the immobilized lipase on activated carbon was analyzed using transmission electron microscopy (TEM) and the immobilized lipase exhibited a catalytic activity of 2.95 U/mg. Biodiesel synthesis was carried out with 50 g of CPO and 3 g of immobilized lipase as a catalyst, at 30°C for 24 h, with gradual methanol addition. The biodiesel was then analyzed, showing an acid value of 1.94 mg-NaOH/g, a saponification value of 143.61 mg-KOH/g, a free glycerol content of 0.06%-mass, a total glycerol content of 0.23%-mass, an ester content of 95.70%, a density of 872.09 kg/m³ at 40°C, and a kinematic viscosity of 6 mm²/s at 40°C. This study offers a more sustainable and cost-effective method for biodiesel production, highlighting the potential of immobilized enzymes to enhance renewable energy practices.

Thermodynamic and Structural Analysis of Proximity-Induced Transitions in Surface-Grafted Polymer Pairs

Porpieng Kullohamongkol — 2025-09-01

This study aims to investigate structural transitions in grafted polymers by varying interpolymeric distance and surface interaction strength using coarse-grained modeling and parallel tempering simulations. We examine the behavior of two grafted polymers on a smooth surface, utilizing the flexible homopolymer model and parallel tempering simulations. Focusing on the interplay between distance separating the polymer chains and the strength of their interaction with the surface, we analyze thermodynamic quantities and structural parameters. Our results demonstrate that at larger interpolymeric distances, adsorption transitions from desorbed to adsorbed expand states are observed, followed by collapse and freezing transitions at lower temperatures. Increasing surface interaction strength shifts these transitions to higher temperatures. At smaller interpolymeric distances, the polymers remain entangled, preventing the observation of collapse transitions and resulting in only adsorption transitions at higher temperatures and freezing transitions at lower temperatures. Without surface attraction, only collapse and freezing transitions are observed. These findings emphasize the importance of structural thermodynamic quantities in identifying these transitions and highlight the significant role of interpolymeric distance and surface interaction strength in the behavior of grafted polymers. This study provides valuable insights for designing and optimizing polymer-grafted surfaces, contributing to advancements in materials science and engineering.

Evaluation of the Antioxidant and Antihyperglycemic Activity: A Comparative Study of Shallot (Allium ascalonicum L.) Peel and Bulb Ethanol Extracts

M. Rifqi Efendi — 2025-09-01

Diabetes Mellitus (DM), known as hyperglycemia, is a growing global health concern. Among medicinal plants explored for their potential in diabetes treatment, Allium ascalonicum L. (shallot) has gained significant attention. This study investigated the effectiveness of shallot peel and bulb extracts as antihyperglycemia activity in alloxan-induced diabetic rats. The total phenolic and flavonoid contents, and antioxidant activity of the extracts were also assessed. Shallot peel and bulb were extracted using ethanol-based maceration, followed by total phenolic content (TPC) and total flavonoid content (TFC) evaluation using the Folin–Ciocalteu and aluminium chloride methods, respectively. Antioxidant activity was determined by the DPPH radical scavenging assay. Diabetic rats were divided into four groups: negative control, positive control (metformin), and two treatment groups receiving 150 mg/kg of shallot peel or bulb extract for 10 days. Parameters such as fasting blood glucose, body weight, urine volume, food, and water intake were also monitored. The results showed significantly higher TPC in peel (347.6±1.7 mg GAE/g) than bulb (78.7±1.90 mg GAE/g), with p = 0.001 (p < 0.05). Peel also had higher TFC (56.60±1.63 mg QE/g vs. 30.4±0.81 mg QE/g in bulb), with p = 0.001 (p < 0.05) and superior DPPH scavenging capacity (IC₅₀ of 124.814 μg/mL compared to 1,712 μg/mL in bulb extract). Both extracts significantly reduced fasting blood glucose levels, with the peel extract being the most effective in glycemic control, while the bulb extract showed greater improvement in diabetic symptoms. These findings suggest that ethanol extracts of shallot peels and bulbs are promising natural antioxidants with antihyperglycemic properties. Their phenolic and flavonoid richness supports their potential in diabetes management.

Transitioning Science and Technology Parks in Indonesia Towards a Low-Carbon Economy: An Emissions Accounting Framework and Recommendation

Arie Rakhman Hakim — 2025-09-02

Science and technology parks (STPs) are primarily intended to foster innovation and support a knowledge-based economy. However, activities within STPs also contribute to greenhouse gas (GHG) emissions, which necessitate strategic mitigation efforts. This study aimed to develop a framework for calculating GHG emissions in STPs in Indonesia and to explore implementable low-carbon strategies. In this study, it was found that the main source of emissions in STPs was electricity consumption (68%), followed by emissions from refrigerants and other fugitive emissions (84% of direct emissions). The results led to the identification of four main pillars to support low-carbon strategies in STPs based on environmental initiatives: targeted environmental policies, technology and infrastructure governance, education and collaboration, and revenue streams. This study highlights the importance of a holistic approach to emissions management in STPs to support the transition to a low-carbon economy and ensure long-term sustainability.

Morphological Variability, Seed Germination and Vulnerability in Sapote (Colicodendron scabridum [Kunth] Seem.)

Guillermo Delgado Paredes — 2025-09-02

The “sapote” Colicodendrum scabridum (Kunth) Seem. is an emblematic coastal species in the seasonally dry tropical forest; however, it is highly vulnerable due to indiscriminate logging and habitat destruction resulting from agro-industrial expansion. This study aimed to characterize specially the morphological variability of fruits and seeds, evaluate seed germination percentage, and analyze the vulnerability status of C. scabridum collected from a 60-hectare area in the Salas District (Lambayeque, Peru). We collected fruits, seeds, and leaves from 12 accessions and assessed their morphological traits. The analysis revealed significant variations in fruit size and shape, leaf dimensions, fruit weight, and seed count. Additionally, germination rates exhibited considerable variability among the fruit samples. The species' vulnerability is underscored by the ongoing destruction of its natural habitat. This study highlights the urgent need for conservation efforts by rural communities, government and academic authorities.

Development of Quantitative PCR Method for Quantifying Streptococcus thermophilus Growth During Batch Culture

Lin Yunyi — 2025-09-02

Streptococcus thermophilus is a thermophilic lactic acid bacterium that is commonly used in food fermentation. However, quantifying bacterial populations using conventional culture-dependent assays is laborious. The genome-based method has been recognized as an alternative rapid method. In this study, we developed a method to use a specific gene of S. thermophilus, the glucokinase gene (GlcK), by quantitative PCR (qPCR). A 139-bp PCR product was successfully cloned and used to generate a DNA standard curve by plotting the threshold cycle (Cq) versus log DNA concentration of plasmid DNA, with an amplification efficiency of 97.2%. Coefficient of variation was calculated by considering both Cq and bacterial cells enumerated by plate counts, which indicated a log CFU/mL (1.69-6.56) and log DNA copies (2.07-6.03). This linear relationship revealed a quantitative curve (R² = 0.989) with a detection limit of range from 2.07 to 6.03 log copies per reaction. In terms of efficiency and repeatability, the relative standard deviations (RSDs) were in the range of 92-110% and 0.01%, respectively. Lastly, we used the developed qPCR method to determine the growth curves of bacterial cells and the specific growth rate (m) during batch culture for 24 h. The established method facilitated the determination of specific growth rates, showing a specific growth rate of 0.57 h^-1 with lactose supplementation and 0.30 h^-1 in the absence of lactose. Hence, qPCR-based methods facilitated reliable quantification of S. thermophilus during fermentation.

Optimization of White Popinac Substrate Composition for Milky Mushroom Cultivation

Eakaphun Bangyeekhun — 2025-09-02

This study was aimed at optimizing the substrate composition of white popinac wood chips for milky mushroom cultivation. Response surface methodology and central composite design were used to evaluate the effects of rice bran, dolomite, and phosphate rock concentrations. The optimized substrate composition, which was determined to maximize biological efficiency, consisted of 5% rice bran, 2.5% dolomite, and 2.5% phosphate rock, which yielded a biological efficiency of 89.72%. Proximate analysis of the cultivated mushrooms revealed 82.15% moisture, 20.14% protein, 1.60% fat, 64.87% carbohydrate, and 8.29% ash content. The glutathione concentration was 58.46±6.14 μM. The DPPH and ABTS radical scavenging assays showed IC50 values of 93.20±8.90 and 67.08±9.61 mg/mL, respectively. The results of this study underscore the potential of organic milky mushroom cultivation and highlight the suitability of white popinac wood chips as a sustainable substrate.

Effects of Incorporation of Aloe vera Leaf Extract on the Synthesis and Characteristics of Bacterial Cellulose Produced by Komagataeibacter xylinus

Nuratiqah Ismail — 2025-09-02

Bacterial cellulose (BC) is a non-toxic, high-purity, and biocompatible polymer that is abundant in various bacteria and does not contain lignin, hemicellulose and pectin found in plant cellulose. High concentrations of carbon sources can limit yields of BC. One potential solution to enhance BC production is the use of elicitors like plant extracts; however, the use of plant extracts such as Aloe vera leaf extract remains limited. Therefore, the current study aimed to investigate the effects of Aloe vera leaves on BC properties, glucose consumption, and synthesis rate by Komagataeibacter xylinus to increase BC volumetric production. Aloe vera extract was incorporated into the culture medium (given the conditions used), and BC was analyzed after 5 to 7 days of fermentation. The fermentation process at 30°C showed that increasing Aloe vera extract volume to 30% (v/v) improved glucose consumption, resulting in 3.35 g/L of BC accumulated in culture flasks. Adding different amounts of Aloe vera leaf extracts to the bacteria culture altered the morphology of the BC film and trapped Aloe vera extract inside the BC fibers. The treatment with 30% (v/v) Aloe vera leaf extract also resulted in a less homogeneous Aloe-BC morphological surface structure. The X-ray diffractometer (XRD) crystallinity index of control BC improved from 83.70% to 93.70% compared to the 30% Aloe-BC. According to the IR spectral analysis, the presence of amine groups in dried BC samples is confirmed by the detected absorption in the 1536-1635 cm⁻¹ range, which indicates N–H bending vibrations. In conclusion, including Aloe vera leaf increased glucose intake, enhanced BC biomass, and altered the shape of the BC.

Enhanced Enzyme-assisted Aqueous Extraction of Polyphenols from Ficus auriculata Fruits: Optimization and Assessment of Bioactive Properties

Pham Thi My Tien — 2025-09-02

The Ficus auriculata fruit is not only a nutritionally valuable food but also a rich source of polyphenols, which contribute to cardiovascular health, cancer prevention, blood sugar regulation, and cholesterol reduction. This study aimed to optimize the extraction conditions for polyphenol-rich extracts from fig fruit using response surface methodology (RSM). The effects of enzyme concentration, solvent-to-solid ratio, and extraction time on total polyphenol content (TPC) were evaluated. The optimized conditions were determined to be an enzyme concentration of 0.74%, a solvent-to-solid ratio of 23:1 (mL/g), and an extraction time of 65 min. Under these conditions, the TPC in the extract reached 2.65 g GAE/100 g dry matter, closely aligning with the predicted value of 2.70 g GAE/100 g dry matter. Scanning electron microscopy (SEM) analysis confirmed significant structural modifications in enzyme-treated samples, indicating enhanced extraction efficiency. Furthermore, GC-MS profiling identified 13 bioactive compounds in the optimized extract, suggesting their potential role in antioxidant activity. These findings highlight the potential of F. auriculata fruit as a valuable source of natural polyphenols, supporting its application in functional foods and pharmaceutical formulations.

Enzymes Involved in Lignocellulose Decomposition and Effects of Fungal Pretreatment During Solid-state Fermentation of Lignocellulosic Agricultural Residues: The Case of Trametes versicolor

Hieu Linh Duong — 2025-09-02

Ligninolytic fungi are considered useful for different biotechnological uses such as lignocellulose pretreatment for biorefinery applications, composting, mushroom production, or bioremediation purposes. Enzymes contributing to lignocellulose breakdown represent valuable biocatalysts. Trametes versicolor is a well-known ligninolytic white-rot basidiomycete capable of growing on different lignocellulosic materials. In the present study, the use of T. versicolor, which secretes several enzymes capable of degrading lignocellulosic biomass, was evaluated from two biotechnological aspects including fungal crude extracts and effects on enzymatic saccharification of wheat straw. We used 20-day-old wheat straw cultures of this fungus to characterize its lignocellulose-decomposing multi-enzyme complex. At the end of the cultivation period, losses of approximately 41% in lignin and 30% in total dry mass were observed relative to their initial values. A total of 17 enzyme activities, each acting differently on the polysaccharide components of the lignocellulosic substrate, and lignin-modifying enzyme activities (laccase, peroxidases) were investigated in aqueous extracts of fungal cultures. The activities of carboxylesterase (substrate: 4-nitrophenyl valerate), endo-1,4-β-D-glucanase (substrate: 2-hydroxyethylcellulose), and laccase were found to predominate. In summary, fungal crude extracts containing different enzyme activities may be promising for various biotechnological purposes. Trametes versicolor effectively pretreated wheat straw, significantly increasing reducing sugar levels compared to controls.

Study of the Potential Application of Hydroxyapatite (HAPt) from Cattle Bone in the Tooth Demineralization Process

Muhammad Irfan Said — 2025-09-02

One of the animal by-products that includes most inorganic compounds, specifically calcium and phosphorus, is cattle bone. In this study, the possible use of HAPt derived from cattle bone waste to counter tooth demineralization was assessed. A 5x5 unidirectional pattern and a completely randomized design were used in the experimental design of the investigation. Five different types of soaking material treatments were used: S0 = acetate buffer (AB) (control); S₁ = AB+NaF 10 mg/L (w/v); S₂ = AB+HAPt 25 mg/L (w/v); S₃ = AB+HAPt 50 mg/L (w/v); and S₄ = AB+HAPt 100 mg/L (w/v). The following periods were observed: 3, 6, 9, 24, and 48 h. The findings demonstrated that the percentage of tooth mass loss during the soaking process was significantly (p<0.01) impacted by variations in the kind of material and HAPt level. Compared to other treatments, HAPt at 50 and 100 mg/L had the best ability to slow down the rate at which teeth were demineralizing. The tooth wall segment was considerably protected from fracture during the demineralization process in AB solution pH 5, 1 M, by the application of HAPt from cattle bone at 100 mg/L. The study's overall findings demonstrated that HAPt, which is made from cattle bone waste from the foreleg (Os metacarpus), may be used in dental treatment to slow down the rate of tooth demineralization.

OptISNV2: An Effective Deep Learning-Based Approach to Content-Based Image Retrieval Systems

Rajasekharam Gulla — 2025-09-02

There has been a significant increase in the production of images on the internet in recent years, necessitating the development of automated content management systems. The content-based image retrieval (CBIR) model has been developed to lessen reliance on the textual annotations-based picture retrieval model. A range of features-classifier combinations-based CBIR techniques are available for analyzing query image content and retrieving appropriate images. While these techniques improve retrieval performance in single-class scenarios, semantic similarity between images of various classes causes a considerable loss in performance in multi-class search contexts. This research proposes a novel deep learning-based technique for a content-based image retrieval system. Initially, the input/query images were taken from three publicly available datasets: Kvasir, CIFAR-10, and Corel-1k. Then, noise reduction contrast enhancement and normalization in pre-processing were performed to better understand the image features. After that, the picture's image texture, color, and shape attributes were retrieved for classification and similarity matching using the SE-ResNeXt-101 technique. Then, from the query picture and database pictures, these attribute vectors were utilized to categorize the dataset pictures using the Improved ShuffleNetV2 method; this method measures the similarities between pictures to retrieve the most alike DB pictures given as the query. The Improved Mayfly Optimization Algorithm (IMOA) was used to increase retrieval performance. The outcomes of the experiments show that the approach performed better in terms of picture retrieval than the most advanced CBIR techniques currently in use.

Effects of Fresh Ivy Gourd Leaves (Coccinia grandis (L.) Voigt) Added to Concentrate Diets on Production and Egg Quality of Kabinburi Egg Duck of 21–32 Weeks Old

Wiwat Waramit — 2025-09-02

This study aimed to investigate the effects of the addition of fresh ivy gourd leaves in the diet on the production and egg quality of Kabinburi egg ducks that were 21-32 weeks old and weighed 1,476.30±25.80 g. A total of 120 female Kabinburi egg ducks were maintained in litter cages; each measuring 1×1 duck. The treatment included the addition of fresh ivy gourd leaves at 0, 5 and 10% in concentrate diets. A completely randomized design was used in this study. The production performance and egg quality of the Kabinburi egg ducks of 21-32 weeks old were evaluated. The addition of fresh ivy gourd leaves to the diet had no significant impact on the production performance and quality of the eggs (p>0.05), except for the egg mass (g) and yolk color. The egg mass (g) tended to show significant differences (p=0.08) between the treatment groups when compared with the control group, while a significant increase (p<0.05) in yolk color was observed when 10% fresh ivy gourd leaves were added. An increase in the level of the fresh ivy gourd leaves resulted in a linear increase in egg mass (g) and yolk color (p<0.05). The addition of 10% of fresh ivy gourd leaves increased the egg mass (g) and yolk color but did not improve the production performance, production, physical appearance, and quality of Kabinburi egg duck.

Interconnections of Oral Microbiota and Systemic Health: Insights from Recent Research on Periodontal Diseases

Abirami Gunasekaran — 2025-09-02

This review explores the intricate relationships between oral microbiota, periodontal diseases, and systemic health. Recent studies have revealed that alterations in the oral microbiome can significantly impact systemic conditions such as cardiovascular disease, diabetes, and rheumatoid arthritis. Pathogens such as Porphyromonas gingivalis and Tannerella forsythia are frequently implicated in these associations, contributing to systemic inflammation and disease progression. The review also examines how behavioral factors, particularly smoking and dietary habits, influence the composition of the oral microbiome and exacerbate periodontal conditions. Technological advancements in diagnostic methods, including multiplex real-time PCR and next-generation sequencing, have enhanced our understanding of microbial dysbiosis and its implications for disease severity. Furthermore, innovative therapeutic strategies such as Oral Microbial Transplantation (OMT) are being investigated to improve oral health outcomes. By elucidating these complex interactions, this review aims to inform healthcare professionals on effective strategies for the prevention and management of both periodontal diseases and their systemic implications.

Terahertz Wave Technology for Medical Treatment and Diagnosis

Ornnicha Kongwut — 2025-09-02

This article provides an overview of the principles, properties, and medical applications of terahertz waves. Terahertz (THz) waves are electromagnetic waves with frequencies ranging from 0.1 to 10 THz, lying between the microwave and infrared regions of the spectrum. They possess unique properties such as the ability to penetrate various materials, a non-ionizing nature, and specific spectral responses to certain biological substances. The working principle of terahertz imaging relies on measuring the absorption, reflection, and scattering of terahertz waves as they pass through biological tissues. Terahertz imaging offers a number of advantages over conventional medical imaging techniques, including higher resolution, better differentiation of soft tissues, and the ability to provide both structural and functional information. Applications discussed in the article include skin cancer detection, dentistry, surgery, and drug monitoring. However, there are challenges and limitations to overcome, such as the need for higher image resolution, miniaturization and improvement of devices, and evaluation of long-term safety. Future opportunities lie in integrating terahertz imaging with artificial intelligence to enhance diagnostic accuracy and efficiency. In conclusion, terahertz waves demonstrate significant potential for various medical applications, offering a safe, non-invasive, and high-resolution imaging modality. While further research and development are necessary to address current limitations, translating this technology into clinical practice could ultimately lead to improved patient care and outcomes.