Creative Science

Enhancement of antifungal efficacy of Bacillus subtilis AS80 by cold plasma technology

2025-03-27T16:36:19+07:00

Pathogenic fungi represented in avocado and other fruit orchards rely predominantly on the application of fungicides. However, the employment of synthetic fungicides is increasingly restricted due to the harmful effects of pesticides on human health and the environment. Therefore, this research aimed to enhance the antifungal efficacy of antagonistic bacteria and to elucidate the enzyme activity underlying their inhibition of fungal development. The antagonistic bacteria, Bacillus subtilis AS80, were induced to mutate by cold plasma technology, and an assessment of antifungal activity was performed. It was found that three mutants named MT144, MT163, and MT165 exhibited significant antifungal activity, with mycelial growth inhibition of 86.3%, 85.2%, and 82.8%, respectively, while the wild type showed an inhibition of 76.4% at 14 days after inoculation. In addition, B. subtilis AS80 and antagonistic mutants exhibited chitinase, cellulase, and amylase activities. Interestingly, the MT123 mutant, which was deficient in antifungal activity, showed a contrasting phenotype, with high amylase activity but no detectable chitinase or cellulase activities. This study suggests that chitinase and cellulase are key enzymatic factors in B. subtilis AS80 and its mutants, mediating their ability to inhibit the growth of pathogenic fungi.

GRAPHICAL ABSTRACT

HIGHLIGHTS

Cold plasma technology is an effective technique to enhance antifungal activity in Bacillus subtilis AS80, which is beneficial to use as a biocontrol agent.
Chitinase and cellulase are key enzymatic factors in subtilis AS80 and its mutants, mediating their ability to inhibit the growth of pathogenic fungi.

Assessment of resistance spot welding parameters on the strength and reliability of AISI 316L stainless steel joints

2025-04-18T09:52:32+07:00

This study investigates how resistance spot welding parameters affect the joint strength and reliability of AISI 316L stainless steel, examining the effects of welding current, welding time, electrode pressure, and holding time. A 2ᵏ full factorial design combined with Weibull analysis was employed to systematically evaluate the influence of each parameter. Results indicate that the optimal welding conditions—4.0 kA welding current, 0.5 s welding time, 0.3 MPa electrode pressure, and 5.0 s holding time—lead to superior joint strength and reliability, achieving an average tensile shear force of 2376.02 N. Examination of the welded specimens revealed a pull-out failure mode and ductile fracture. Unlike previous studies that primarily focused on maximizing strength, this research integrates both strength and reliability assessments, providing a more comprehensive evaluation. The Weibull analysis not only validates findings from conventional analysis of variance, but also provides additional insights into joint reliability, demonstrating an effective alternative methodology for optimizing welding parameters.

GRAPHICAL ABSTRACT

HIGHLIGHTS

A full factorial design combined with Weibull analysis was utilized to evaluate the effects of resistance spot welding parameters on AISI 316L stainless steel joints.
High welding current, short welding time, low electrode pressure, and long holding time were identified as optimal conditions for achieving superior joint strength and reliability.
Weibull analysis provided additional insight beyond ANOVA, enabling simultaneous assessment of strength and reliability, and guiding improved parameter selection for reliable welding.

Antibiotics removal from water by adsorption activated carbon of bacterial cellulose source

2025-04-10T07:18:10+07:00

The overuse of antibiotics in developing countries has exacerbated antibiotic resistance, particularly due to contamination of water systems. This study addresses this challenge by synthesizing activated carbon derived from bacterial cellulose (AC-BC) for efficient adsorption of amoxicillin (AMOX) and cephalexin (CEX) from aqueous solutions. Bacterial cellulose (BC), produced sustainably by Komagataeibacter using waste coconut water, served as the precursor for AC-BC. The synthesized AC-BC exhibited a yield of 19.46±3.92% (dry weight basis) and met ASTM standards in proximate analysis, excluding ash content. Structural characterization revealed a hierarchical pore structure, supported by an iodine number of 1360.59 mg g^-1 and methylene blue adsorption of 240.10±1.04 mg g^-1, with SEM imaging confirming diverse pore sizes. BET analysis demonstrated a high specific surface area (204.68 m² g^-1), total pore volume (0.1475 cm³ g^-1), and average pore diameter (2.8825 nm). Functional groups (hydroxyl, carboxyl, ether) and a semi-crystalline structure were identified via FTIR and XRD, respectively. Optimal batch adsorption conditions (60 mg L^-1 initial concentration, 60-min contact time, 0.2 g adsorbent dosage, pH 7, 30°C) achieved maximum capacities of 4.578 mg g^-1 (AMOX) and 4.288 mg g^-1 (CEX). Adsorption isotherms aligned with the Langmuir model, indicating monolayer adsorption, while kinetics followed a pseudo-second-order model. Thermodynamic analysis revealed a spontaneous (ΔG° < 0), exothermic (ΔH° < 0), and entropy-driven (ΔS° > 0) process. These findings highlight AC-BC as a promising, low-cost adsorbent for antibiotic removal. The use of renewable BC from agro-industrial waste underscores its environmental and economic viability, offering a sustainable strategy to mitigate water contamination and combat antibiotic resistance.

GRAPHICAL ABSTRACT

HIGHLIGHTS

Activated carbon of bacterial cellulose sources (AC-BC) has been used as highly effective adsorbent for amoxicillin (AMOX) and cephalexin (CEX)
Bacterial cellulose source is a natural, renewable, environmentally friendly and low-cost.

Response surface methodology as a statistical model for nutrient optimization to enhance biomass and bioactive phycobiliproteins production in cyanobacterium Nostoc sp. SW02

2025-05-01T09:58:34+07:00

Phycobiliproteins (PBPs) are water-soluble pigments involved in the photosynthesis of cyanobacteria. They are valuable natural colorants for biotechnological applications due to their significant biological properties. This research was the first to study the impact of NaNO₃, Na₂CO₃, and K₂HPO₄ nutrient variations on the production of biomass and PBPs in the cyanobacterium Nostoc sp. SW02. The experiments utilized the response surface methodology with the Box-Behnken design for nutrient optimization. The quadratic equations showed that the models sufficiently aligned with the experimental data and could explain the combined influence of factors with statistical significance. The addition of NaNO₃, Na₂CO₃, and K₂HPO₄ at concentrations of 2.0, 0.02, and 0.035 g L^-1, respectively, provided the maximum biomass and PBPs production at 0.967 g L^-1 and 13.89% yield, representing increases of 30.67% and 8.86%, compared to normal culture medium. The validity of the predicted model was confirmed, indicating its potential application in both small and large-scale cultivations. This study developed a model that could be applied for the commercial production of natural cyanobacterial colorants for their potential use in food and cosmetics industries.

GRAPHICAL ABSTRACT

HIGHLIGHTS

Key nutrient factors (NaNO₃, Na₂CO₃, and K₂HPO₄) were analyzed for their impact on productions of biomass and phycobiliproteins.
Statistical modeling of response surface methodology used for nutrient optimization.
The quadratic equations could explain the combined influence of factors with statistical significance.

Development of beverage nutritional assessment application; sugar, fat and sodium for diabetes mellitus

2025-05-19T15:46:43+07:00

The purpose of this research was to the development of beverage nutritional value assessment application for diabetes mellitus risk group. The nutritional information was collected for 422 popular beverages in the THAT-Tambon Municipality, Chiang Khan District, Loei Province. This included 392 items from convenience stores with Guideline Daily Amounts (GDA) labels that an overview of the nutritional content as the percentage of energy and key nutrients like energy, fat, saturated fat, sugar, and salt/sodium as a percentage of what an average person should consume in a day, and 30 from local cafes, with nutritional content determined by food and nutrition experts through ingredient analysis. The beverages were categorized into 11 groups, including milk and dairy drinks, juices, carbonated drinks, grain-based drinks, coffee, tea, herbal drinks, and others (e.g., Oleang, Plum Lemon, Jelly Shake). The average sugar content was approximately 15.6g per serving, indicating high-moderate sugar levels that require cautious consumption. The application comprises three modules: (1) an administrator module for managing beverage and user data, (2) a general user module for searching beverages, viewing nutritional information, assessing dietary intake, and planning daily consumption, and (3) a member module with additional features for saving and retrieving personal beverage records. The application was developed using HTML5, CSS, JavaScript, PHP, and connected to the relational database using MySQL. Research tools included questionnaires and nutritional analysis based on standard methods. A preliminary evaluation by five software experts showed high effectiveness ( = 3.84, S.D. = 0.15), and user satisfaction from a group of 14 target users was also high ( = 4.10, S.D. = 0.37). The application is expected to support health awareness and help reduce the risk of diabetes by promoting informed beverage choices.

GRAPHICAL ABSTRACT

HIGHLIGHTS

Assess drink nutrition values.
Plan daily beverage intake.
Designed for diabetics.

Monitoring and evaluation of socioeconomic impacts under the project “Enhancing value addition to sugarcane products through BCG principles to create a prototype of self-sustainable, integrated sugarcane farmer community enterprises”

2025-04-22T12:43:45+07:00

This research aims to evaluating the success of a project within the framework of sustainable development, specifically through alignment with the Sustainable Development Goals (SDGs), Environmental, Social, and Governance (ESG) principles, and the Bio-Circular-Green Economy (BCG) model. The case study focuses on the project entitled "Enhancing the Value of Sugarcane Products through BCG Principles to Establish a Prototype of a Self-Sustaining, Integrated Sugarcane Farmers' Community Enterprise." The findings results that the project successfully addressed existing challenges and enhanced effectiveness in alignment with sustainability objectives. However, in the long term, the evaluation of the project's impact revealed a lack of efficiency, as evidenced by the Social Return on Investment (SROI) analysis, which yielded a ratio of only 0.64. This case study underscores the importance of selecting appropriate conceptual approaches for problem-solving and project development, as well as the need for comprehensive strategies for long-term impact monitoring and valuation.

GRAPHICAL ABSTRACT

HIGHLIGHTS

The project achieved short-term goals aligned with SDGs, ESG, and BCG, but some activities were not sustained post-implementation.
Social Return on Investment (SROI) was low at 0.64, indicating limited long-term efficiency relative to sustainability investments.
Emphasizes the need for contextualized development strategies and long-term impact evaluation to realize future value.

Enhancing the value of reclaimed asphaltic pavement as aggregate material in concrete work

2025-05-18T12:22:05+07:00

This study explores the use of reclaimed asphalt pavement (RAP) as a sustainable and cost-effective substitute for coarse natural aggregates in concrete. Concrete mixtures were prepared with RAP replacement levels of 0%, 15%, 30%, 50%, and 80% by weight, aiming for a minimum compressive strength of 240 ksc in 15x15x15 cm cube specimens after 28 days of curing. Key engineering properties including compressive strength, flexural strength, and modulus of elasticity were evaluated. The results show that increasing the RAP content leads to greater deviation from optimal aggregate gradation and a gradual decrease in both compressive and flexural strengths. Nevertheless, mixtures containing up to 30% RAP met the target compressive strength (exceeding 240 ksc) and achieved flexural strengths over 24.6 ksc 11% above the design specification. At a 50% RAP replacement, compressive strength remained above 180 ksc and flexural strength still exceeded 24.6 ksc. The modulus of elasticity decreased with higher RAP content, ranging from 5,000 to 25,000 MPa (53,986 to 254,930 ksc). Economically, using 30% RAP reduced the production cost by 6.89%, while a 50% RAP substitution resulted in a 12.03% cost reduction compared to conventional concrete. These findings highlight RAP’s potential as a viable alternative in concrete for applications with moderate strength requirements.

GRAPHICAL ABSTRACT

HIGHLIGHTS

A 30% RAP replacement in concrete achieved a compressive strength exceeding 240 ksc and a flexural strength greater than 24.6 ksc, which is 11% above the design specification.
With a 50% RAP replacement, the concrete maintained a compressive strength above 180 ksc and a flexural strength exceeding 24.6 ksc, although the modulus of elasticity decreased with higher RAP content.
Economically, a 30% RAP replacement reduced production costs by 6.89%, while a 50% replacement resulted in a 12.03% cost reduction compared to conventional concrete.

The type and composition of the main elements in the mud that influence the color shades of purple silk

2025-05-27T15:55:38+07:00

This research aimed to study the types and compositions of main elements in mud that influence the shades of purple silk. The population was purple silk threads, and the sample consisted of purple silk threads dyed with sappan heartwood and subsequently overdyed with mud. All samples were obtained from the Ban ta long silk weaving group, located in tung wang subdistrict, sa tuek district, buriram province. The analysis of the element composition in the mud was conducted using the x-ray fluorescence energy dispersive spectrometer (EDXRF) technique. The results revealed the presence of iron oxide ions in the mud solution at concentrations equivalent to ferrous sulfate ion solutions exceeding 300 ppm. When silk threads are dyed with an extract from sappan heartwood using alum as a mordant, they attain a red hue characterized by CIELAB color values of L* 60.81, a* 30.90, and b* 13.14. Subsequent overdyeing with a mud solution alters the silk's color to purple, with corresponding CIELAB values of L* 43.49, a* 7.90, and b* 0.17. This shift in color is attributed to the presence of iron ions in the mud solution, which interact with the dye, leading to a perceptible change in hue. Furthermore, the extract from sappan heartwood (Caesalpinia sappan) contains a red pigment known as brazilein, which can form an insoluble complex compound with iron ions. This compound exhibits a distinctive purple hue that binds effectively to silk fibers or protein fibers, resulting in uniquely colored natural-dyed silk fabric that reflects a distinctive cultural identity. The findings contribute to community-based knowledge that can be passed on to future generations or individuals interested in studying this valuable traditional wisdom. Moreover, this knowledge has the potential to generate sustainable household income, reduce urban migration, alleviate poverty, and promote environmentally friendly practices.

GRAPHICAL ABSTRACT

HIGHLIGHTS

“If silk threads dyed with sappan heartwood are then fermented in mud, the result may be a purple color.”
The color producing compounds in sappan heartwood are brazilin and brazilein.
The color in silk threads changes from reddish orange to purple after being fermented with mud.