Journal of Applied Agricultural Science and Technology

Experimental Study on Soaked Corn Cobs as Feedstock for Biomass Gasification in an Open Downdraft Gasifier

Muhtar Kosim — 2025-05-25

Fossil fuels, which account for 83% of Indonesia's total energy supply, are depleting and environmentally unsustainable. Corn cob biomass, with an annual yield of 4.34 million metric tons, presents a viable alternative. Through gasification at temperatures of 700–1200°C, corn cobs can be converted into combustible gas or syngas. To enhance syngas yield, the corn cob gasification process can be optimized by increasing moisture content through soaking. However, experiments with soaked corn cobs have shown a significant decline in temperature and gasification zone performance. The gasification temperature decreased from 1024°C to 614°C, falling below the 700°C threshold. Additionally, the gasification zone shifted significantly downward in the reactor. This reduction is attributed to the high moisture content of the corn cobs, which exceeded 30%, reaching 56.78%, allowing the gasification process to last for 48 minutes. Before the gasifier ceased operation, syngas production achieved a promising average thermal power of 1.76 kW with an efficiency of 7.14%. These findings indicate that soaked corn cobs can serve as biomass gasification feedstock, provided the moisture content does not exceed 30%.

The Effect of Pesticide Residues on Environmental Quality in the Kromong II Watershed, Pacet District, Mojokerto Regency

Dimas Ganda Permana Putra — 2025-05-25

The river basin serves multiple ecological and socio-economic functions for the local community, particularly the Kromong II Watershed in Pacet District. A major issue in the upstream area of the watershed is the use of pesticides by local residents in agricultural land management. Excessive pesticide use leads to significant environmental residue accumulation. This study aimed to assess pesticide residue levels, evaluate the quality of irrigation water and soil fertility in rice fields, and map polluted locations using the ArcGIS 10.3 remote sensing application. The analysis was conducted at three designated research sites: Stations I, II, and III. Biochemical Oxygen Demand (BOD) was analyzed using the SNI 6989.72:2009 standard, while Chemical Oxygen Demand (COD) was measured following the SNI 6989.2029 method at the Mojokerto Regency Environmental Agency (DLH) Laboratory. Soil organic carbon (C-organic) was analyzed using the IKP-208 Organic Carbon Test, and total nitrogen (Total N) was determined through spectrophotometric analysis at the PT Graha Mutu Persada Laboratory. Metomil was analyzed using the Liquid Chromatography–Mass Spectrometry (LC-MS) method, while Profenofos was analyzed using Gas Chromatography–Mass Spectrometry (GC-MS). The study found that the highest levels of BOD and COD were recorded at Station III, with values of 11.4 mg/L and 28.6 mg/L, respectively. The highest total nitrogen (Total N) concentration was observed at Station I, measuring 0.14%, while the highest soil organic carbon (C-organic) content was found at Station III, at 7.87%. The LC-MS analysis of methomyl residues showed the highest concentration at Station III, with a value of 0.002 mg/L in irrigation water samples. Similarly, the GC-MS analysis of Profenofos residues indicated the highest concentration at Station II, measuring 8.25 ml/L. Based on these findings, it can be concluded that pesticide residue pollution, particularly from Profenofos, is most severe in the irrigation channel at Station II.

The Impact of Withering Pre-Processing and Distillation Durations on Yield and Quality of Citronella Oil

Usman Ahmad — 2025-05-25

The global essential oil market is expanding rapidly, driven by demand from the pharmaceutical, cosmetic, and food industries. This has positioned Indonesia as a key producer and exporter of citronella essential. However, inconsistent processing methods lead to variable quality and suboptimal oil yields. This study addresses this gap by investigating how withering duration (0-72 hours) and distillation time (2-4 hours) affect yield and quality of distilled oil from Cymbopogon nardus (Mahapengiri variety). The results show that the highest oil yield (1.14%) was achieved with 72 hours of withering followed by 4 hours of distillation, demonstrating that prolonged withering significantly enhances extraction efficiency by reducing moisture content and facilitating oil release from plant cells. Quality assessments revealed that extended processing improved key physical parameters, including density (0.8897 g/cm³) and refractive index (1.4694), which conformed to Indonesian export standards (SNI 06-3953-1995). Chemical analysis using gas chromatography-mass spectrometry (GC-MS) indicated that optimal processing conditions increased the concentrations of citronellal (43.24%) and geraniol (21.73%), critical compounds that enhance the oil’s market value. However, longer distillation times also intensified the oil’s color, shifting it from clear to a deep yellow, which may influence consumer preference despite meeting industry chromatic standards. The study highlights the trade-offs between yield, quality, and visual characteristics in citronella oil production. These findings provide actionable insights for Indonesian producers aiming to optimize post-harvest techniques and improve the competitiveness of citronella oil in global markets.

Thermal Properties and Cooling Simulation of Red Dragon Fruit Using the Finite Difference Method

Lailatul Maghfiroh — 2025-05-25

Red dragon fruit (Hylocereus polyrhizus) can be transformed into various processed products, such as chips, jam, and juice. However, thermal processing may significantly alter its physical and chemical properties. As the calorific properties vary among different fruits, this study aims to measure the thermal properties of red dragon fruit. By measuring its thermal properties, red dragon fruit can be processed with improved energy efficiency and optimized thermal management. This study aims to examine the thermal properties and perform a cooling simulation of red dragon fruit. The cooling simulation, based on one-dimensional radial thermal flow, was conducted using the spherical heat equation explicitly discretized by the Forward Time Central Space (FTCS) scheme within the Finite Difference Method (FDM). The specific heat, thermal diffusivity, and thermal conductivity of red dragon fruit were 3.827 kJ/kg ^oC, 9.18 x 10^-4 cm²/s, and 0.34 W/m ^oC, respectively. The overall average coefficient of determination (R²) from the validation test of the simulation results was 0.9654. Based on these findings, the one-dimensional (radial) discretized heat transfer equation model can be used to predict the temperature distribution in spherical fruit over time, based on its thermal diffusivity. However, this approach has limitations. Future research would benefit from measuring the thermal diffusivity of whole red dragon fruit and applying a three-dimensional discretized heat transfer equation to obtain more accurate results and minimize potential errors.

The Effect of Cultivation Media on Matriconditioning Technique and the Concentration of Onion Peel Waste PGR on the Viability and Yield Rice (Oryza sativa) Through the Metabolic Activity of the Seed

Alfiyyah Nur Amany — 2025-05-25

A major limiting factor for rice production in the tropics is the decline in seed quality due to storage duration and environmental conditions. Rice seeds are often stored for extended periods, making seed expiration unavoidable. Expired seeds frequently undergo quality deterioration. Therefore, an effective approach is needed to mitigate quality decline and sustain rice production. This study aims to evaluate the effectiveness of different matriconditioning techniques and various concentrations of onion peel waste-derived plant growth regulators (PGRs) in maintaining seed viability and rice yield. The research was conducted using a Completely Randomized Design (CDR) with a two-factor experimental setup and three replicates. The first factor was the matriconditioning medium, consisting of three levels: M₁ (soil), M₂ (soil + husk charcoal), and M₃ (soil + husk ash). The second factor was the concentration of onion peel waste-derived PGR, consisting of four levels: K₁ (0% – water), K₂ (25% – 250 mL onion peel waste PGR per 1000 mL), K₃ (50% – 500 mL onion peel waste PGR per 1000 mL), and K₄ (75% – 750 ml onion peel waste PGR per 1000 mL). The results showed that matriconditioning with soil and husk charcoal, along with 25% onion peel waste-derived PGR, enhanced rice seed viability. Additionally, a 75% concentration of onion peel waste PGR significantly influenced the weight of 1000 grains and the total harvested grain weight.

Deep Learning Approaches for Plant Disease Diagnosis Systems: A Review and Future Research Agendas

Verry Riyanto — 2025-05-25

To identify novel advancements in plant diseases detection and classification systems employing Machine Learning (ML), Deep Learning (DL), and Transfer Learning (TL), this research compiled 111 peer-reviewed papers published between 2019 and early 2023. The literature was sourced from databases such as Scopus and Web of Science using keywords related to deep learning and leaf disease. A structured analysis of various plant disease classification models is presented through tables and graphics. This paper systematically reviews the model approaches employed, datasets utilized, countries involved, and the validation and evaluation methods applied in plant disease identification. Each algorithm is annotated with suitable processing techniques, such as image segmentation and feature extraction, along with standard experimental metrics, including the total number of training/testing datasets utilized, the quantity of disease images considered, and the classifier type employed. The findings of this study serve as a valuable resource for researchers seeking to identify specific plant diseases through a literature-based approach. Additionally, the implementation of mobile-based applications using the DL approach is expected to enhance agricultural productivity.

Evaluation of the Characteristics and Controlled Release of Citronella Essential Oil in Aromatherapy Necklaces via Sensory Analysis

Alfi Asben — 2025-05-25

Essential oils, including those used in aromatherapy, are currently in high demand as consumers increasingly prefer products made from natural ingredients. Citronella oil, when used as aromatherapy, is intended to relieve headaches, enhance breathing, and produce a warming effect upon inhalation. Aromatherapy necklaces provide a convenient and portable method for delivering the benefits of essential oils. Encapsulation technology addresses the volatility of essential oils in aromatherapy gels by creating a controlled slow-release mechanism, enabling the gradual release of essential oils over a specified period. This study aims to evaluate the characteristics of aromatherapy necklaces and assess the aroma intensity of citronella oil through sensory analysis. Sensory analysis was conducted using semi-trained and trained panelists. The aromatherapy necklace comprises a mixture of gels and emulsions containing encapsulated essential oils, formulated for immediate use. The sensory analysis results indicated that the addition of 10% essential oils yielded the highest scores for color and texture assessments (4.08 and 3.96, respectively), while the addition of 7.5% essential oils produced the highest score for aroma assessment (4.16). The aroma intensity decreased from a score of 6.00 on day 1 to 3.17 on day 7. The gradual and controlled decline in aroma intensity aligns with the intended purpose of the essential oil encapsulation process.

Low Maternal Seafood Intake During Exclusive Lactation Does Not Significantly Affect Milk Protein Content

Ratna Nurmalita Sari — 2025-05-25

Human milk, which contains complex and highly variably biofluid that nourishes and protects the newborn, is the gold standard for infant nutrition. The biological activity of human milk is significantly influenced by proteins. However, the relationship between crude protein in human milk and the amount of milk consumed by mothers during the exclusive breastfeeding period has not been thoroughly investigated. In the current study, 194 healthy women who were exclusively breastfeeding participated in a cross-sectional study to collect human milk samples and complete a quantitative frequent food questionnaire (FFQ). The consumption of cereals, potatoes, sweet potatoes, leafy vegetables, fruits, other vegetables, legumes, nuts, eggs, meats, dairy products, and seafood was grouped based on the consumption of the mother the day before milk collection. The mid-infrared milk analyzer was used to analyze the samples and determine protein concentration. Using the t-test to analyze the impact of partial factors, and the F-test was employed to evaluate the influence of variables concurrently, at a 5% significance level. The statistical relationship between maternal diet and protein content was evaluated. Seafood consumption was categorized as low compared to other groups. Self-imposed maternal food restrictions may be the cause of the reduced seafood consumption. Human milk has an average protein level of 1.02 g/100 ml. According to the statistics, there was no significant correlation between the crude protein content of human milk and seafood consumption. However, a strong correlation was found between the consumption of eggs, legumes, and nuts, suggesting that these foods may impact on the protein content of human milk (p value <0.05). This finding would suggest that to improve the protein content composition of human milk, nursing mothers should consume more local, high-protein foods.

Acceleration of Organic Waste Decomposition: A Comparative Study of ASEM-7 Decomposer Efficiency on Several Organic Wastes

Ana Khalisha — 2025-05-25

Effective organic waste decomposition is vital for sustainable waste management and agricultural productivity. This study investigates the efficacy of ASEM-7—a newly developed decomposer comprising a consortium of seven microorganisms—in accelerating the composting process and enhancing compost quality across various types of organic waste. Five treatment groups were evaluated: paddy straw; animal manure; fruit and vegetable waste; a mixture of fruit and vegetable waste with straw; and a combination of fruit, vegetable waste, straw, and manure. During the decomposition process, key physicochemical parameters— including pH, temperature, moisture content, organic carbon (C-organic), total nitrogen (N-total), and the carbon-to-nitrogen (C/N) ratio—were systematically monitored. The results demonstrated that ASEM-7 significantly enhanced composting efficiency compared to both EM-4 and control (no-decomposer) treatments, achieving optimal pH stabilization (7–8) at a faster rate. Additionally, ASEM-7 reduced moisture content and C/N ratios more effectively, indicating a higher degree of compost maturity. Compost treated with ASEM-7 also exhibited the lowest levels of organic carbon, reflecting superior decomposition efficiency. Although temperature levels remained below the threshold required for effective pathogen elimination, microbial activity successfully facilitated nutrient recycling. The microbial consortium—comprising Bacillus sp., Lactobacillus sp., and Trichoderma sp.—demonstrated high efficacy in degrading recalcitrant organic materials such as straw and manure, thereby improving the compost's nutrient composition. By meeting key compost quality standards—organic carbon (≥15%), total nitrogen (≥0.5%), and a C/N ratio of 15–25—ASEM-7 effectively converts organic waste into high-quality compost. These findings underscore the importance of tailored microbial consortia in advancing sustainable waste management practices and enhancing soil fertility.

Esterified Illipe Butter-Based Fatty Amine as a Bio-Based Multifunctional Additive for NR/BR Blends Reinforced with a Silica/Silane System in Green Tire Tread Development

Mohamad Irfan Fathurrohman — 2025-05-25

The sustainable rubber industry, particularly in the tire sector, is supported by the use of biomaterials such as multifunctional additives. Fatty amine, derived from the esterification of illipe butter, is considered a promising bio-based multifunctional additive for the development of green tires. This research aimed to investigate the effect of varying dosage of fatty amine on the properties of green tire treads based on NR/BR blends reinforced with a silica/silane system. DPG and unmodified illipe butter were used as comparative references. The "magic triangle of tire performance" was employed as a benchmark for evaluating green tire tread performance. The result indicated that both unmodified illipe butter and fatty amine functioned as bio based multifunctional additives, specifically serving as a bio-plasticizer (filler dispersant) and fast-delayed bio-accelerator, respectively. Therefore, they have the potential to substitute DPG in rubber formulations. The combination of unmodified illipe butter and fatty amine at dosages of 2.5 and 1.25 phr, respectively, exhibited similar behavior by enhancing rubber-filler interaction. Consequently, they meet the desirable criteria outlined in the magic triangle of tire performance.

Green Tea Product Development: Integrating QFD with PLS-SEM, BMC, and AHP for Optimal Business Growth

Azrifirwan Azrifirwan — 2025-05-26

Green tea offers numerous health benefits; however, its market sales remain relatively low. PT Mitra Kerinci, the producer of the Likicha brand green tea, reported that only 38% of its annual production was absorbed by the market. This situation underscores the need for a strategic development plan to enhance sales performance. Therefore, an integrated approach combining PLS-SEM, BMC, QFD, and AHP methods was employed to formulate a strategy to increase the sales volume of Likicha green tea. This study aimed to identify consumer preferences for green tea products to develop a product strategy that enhances market absorption. The findings of this study indicate that consumer purchase intentions for green tea are influenced by health benefits, product packaging attributes, and price. A business mapping of the green tea industry was conducted to obtain a comprehensive internal and external analysis. The QFD data analysis identified technical requirements and prioritized component needs for improving green tea production. These results were then used to formulate criteria and strategic alternatives aimed at increasing green tea sales volume. The results indicate that product quality holds the highest priority among the criteria, with a weight of 64.3%. Among the strategic alternatives, sourcing high-quality tea leaves and optimizing processing methods emerged as the top priority, with a weight of 26.2%.

The Effect of Microwave Time and Power on the Tannin Extraction Process from Gambier (Uncaria gambir Roxb.) Using the Microwave Assisted Extraction (MAE) Method

Fakhruzy Fakhruzy — 2025-05-27

Dry gambier extract obtained from gambier plants contains tannins at relatively low levels. Tannins can be obtained by extracting dry gambier using water to achieve high yields within a relatively short processing time. This study aims to analyze the interaction between extraction time and microwave power in the tannin extraction process from gambier using the microwave-assisted extraction (MAE) method to maximize tannin yield. The research method employed was a factorial design (AxB). Factor A was extraction time, consisting of five treatments (1; 2; 3; 4; and 5 minutes) and factor B was microwave power, consisting of five variations (180W; 300W; 450W; 600W and 850W). The results showed that the gambier extraction process using MAE demonstrated an interaction between extraction time and microwave power on the yield produced, but not on the tannin content. The most optimal temperature and power that can be used is 4 minutes at 600W microwave power with a yield of 44.66%. The treatment of temperature and microwave power in the gambier extraction process showed a significant interaction with the extract yield.

Metagenomic Bioprospecting for Lignocellulosic Enzymes from Bacterial Communities of Humus Obtained from Natural and Man-Made Forests in Tomohon, North Sulawesi, Indonesia

Feky Recky Mantiri — 2025-05-29

Lignocellulosic biomass degradation is crucial for various industrial applications. Traditional enzyme discovery methods, limited by culturing constraints, fail to capture the vast enzymatic potential of uncultured microorganisms. Metagenomic bioprospecting provides a culture-independent avenue to explore this untapped genetic diversity. This research characterizes the microbial communities and their functional capabilities in a natural forest (Mahawu Mountain Forest, MMF) and a man-made forest (Tomohon City Forest, TCF) located in North Sulawesi, Indonesia, aiming to assess the influence of forest type on microbial ecological dynamics and lignocellulose degradation mechanisms. Comparative soil analysis revealed MMF had slightly alkaline pH (7.1), cooler temperature (21°C), and dark grayish-brown Andosol, while TCF exhibited a neutral pH (6.9), warmer temperature (23°C), and brown Andosol. High-throughput 16S rRNA sequencing demonstrated that TCF harbors greater bacterial richness (125 vs. 91 observed OTUs) and diversity (Shannon index 4.44 vs. 4.11), likely influenced by anthropogenic activities. Taxonomic profiling showed that Proteobacteria dominate both sites (MMF: 42.37%; TCF: 56.08%), with Actinobacteria significantly more abundant in MMF (34.08% vs. 5.84%). Functional prediction via PICRUSt analysis highlighted TCF’s enrichment in stress-responsive genes and ABC transporters, whereas MMF exhibited elevated lipid metabolism and specialized lignin-degradation pathways (e.g., 3-hydroxyphenylacetate degradation). These findings suggest that TCF's heterogeneous environment supports microbial versatility, while MMF's stable conditions promote specialization in decomposition. Both forests represent promising reservoirs for lignocellulolytic enzyme discovery, with implications for sustainable biotechnological applications. This study underscores the importance of forest management in shaping soil microbial communities and highlights the value of preserving natural ecosystems for future bioresource exploration.