ASEAN Journal of Scientific and Technological Reports

Enhancing Methane Production from Empty Fruit Bunches by Augmented Thermoanaerobacterium thermosaccharolyticum PSU-2

2024-04-29T10:02:38+07:00

The recalcitrant nature of the substrate often limits the anaerobic digestion of Empty Fruit Bunches (EFB). This study investigates the effectiveness of augmenting Thermoanaerobacterium thermosaccharolyticum PSU-2 for the pretreatment of EFB in mono-digestion and co-digestion with Palm Oil Mill Effluent (POME) to enhance biogas production. The augmented T. thermosaccharolyticum PSU-2 demonstrated enhanced cellulolytic and hemicellulolytic capabilities, resulting in improved biogas yield, methane content, and substrate degradation efficiency compared to the control without augmentation. Mono-digestion of EFB with the augmented strain at an S:I ratio of 15:1 achieved a methane yield of 35.13 ± 1.05 m³ CH₄/tonne, representing a 64.31 ± 1.17% improvement over the control. Co-digestion of EFB with POME using the augmented strain further enhanced the methane yield to 46.67 ± 1.40 m³ CH₄/tonne at an S:I ratio of 15:1, representing a 103.00 ± 2.81% improvement over the control. Kinetic analysis revealed improved hydrolysis rates and reduced lag phases in mono-digestion and co-digestion processes. Comparison with other pretreatment methods and energy balance and economic analysis indicated that co-digestion of EFB with POME using the augmented T. thermosaccharolyticum PSU-2 pretreatment is a promising, energy-efficient, and profitable approach for enhancing biogas production from EFB. This study highlights the potential of biological pretreatment using augmented bacterial strains to improve the valorization of agricultural waste streams through anaerobic digestion.

Effects of Rearing Black Soldier Fly Larvae (Hermetia Illucens) from Organic Wastes

2024-04-27T20:11:53+07:00

Organic waste is one of the major environmental problems, and the black soldier fly (Hermetia illucens) larvae can help decompose organic waste. Therefore, this research is interested in studying organic fertilizers' growth, nutritional value, and nutrient contents from the residue of black soldier fly larvae. Four experimental sets of plastic buckets containing organic wastes, i.e., pineapple peels, banana peels, durian peels, and vegetable scraps, were used to trap the black soldier flies and observe the spawning and the number of egg clusters. After that, the 4-day-old black soldier fly larvae were incubated in plastic boxes using different foods for the same duration. Three replicates of the experiment were performed, recording the growth period and size of the soldier fly larvae. The study found that the life cycle of the black soldier fly was divided into 5 stages: egg, larval, prepupal, pupal, and adult stages, in 47–67 days. The black soldier fly larvae fed pineapple peels both in the larval and prepupal stages were the largest, while the larvae fed with durian peels entered the larval stage the fastest. Subsequently, 100 g of fresh black soldier fly larvae samples from four experimental sets were analyzed for nutritional value. It was found that fresh black soldier fly larvae had protein contents of 9.25–10.69 g/100 g and a fat content of 3.29–15.90 g/100 g, which were suitable for use as an ingredient in animal feed to reduce production costs. Then, 100 g of the frass of the black soldier fly larvae fed with durian peels was collected for analysis of the essential nutrients for plants, i.e., nitrogen, phosphorus, and potassium, at about 2.46%, 2.77%, and 3.14%, respectively, which are suitable for use as organic fertilizers for soil amendments.

Thailand’s Maize Prices Forecasting using Ensemble Technique

2024-05-13T18:51:39+07:00

Crop prices forecasting is crucial for farmers, policymakers, and investors. This paper aims to propose suitable machine learning models for forecasting Thailand’s maize prices by implementing and comparing various machine learning algorithms, including regression trees (RT), support vector regression (SVR), ensemble bagging with RT and SVR as the base learner (Bag-RT and Bag-SVR), and random forest (RF). The dataset used in this study is collected from two main sources: the Office of Agricultural Economics in Thailand (OAE) and the investing.com website for the period from January 2002 to August 2023 consist of 260 records and 53 features. Given the dataset numerous independent variables, we applied the recursive feature elimination combined with Pearson correlation feature selection method to reduce feature dimensions by focusing on the most relevant features. The prediction models were trained using 10-folds cross validation and evaluated using three metrics: R-squared (R²), mean absolute error (MAE), and root mean square error (RMSE). The top-performing model, Bag-SVR, achieved the best R² value of 0.961, MAE of 0.234, and RMSE of 0.315 follow by SVR model with R² value of 0.959, MAE of 0.251, and RMSE of 0.333. In contrast, the RT model demonstrated the lowest performance scores with R² value of 0.846, MAE of 0.44, and RMSE of 0.617. In conclusion, our study emphasizes the influence of feature selection on model performance and showcases the potential of machine learning models for accurate maize prices forecasting in Thailand.

Histological Structure and Histochemistry of the Digestive Tract of the StripedTiger NandidFish, Pristolepis fasciata

2024-05-21T10:50:56+07:00

The striped tiger nandid fish, Pristolepis fasciata, is widely distributed in Thailand. However, its diet composition has intensively investigated, the histological profile remains interesting and challenging issues. Therefore, the objectives of this study are to describe the histological structure and histochemistry of the digestive tract of the striped tiger nandid fish. Fifteen adult fish were collected from Songkhla province, Thailand. The digestive tract was fixed in Bouin’s solution, and followed by basic paraffin techniques. The 5 µm sections were stained with hematoxylin and eosin (H&E), periodic acid Schiff’s (PAS), alcian blue (AB) pH 2.5 and pH 1.0, and Masson's trichrome (MT). The results revealed that the wall of the digestive tract comprised of four layers: mucosa, submucosa, muscularis, and serosa. The mucous and goblet cells in the esophagus exhibited positive staining with PAS, AB pH 2.5, and pH 1.0. The stomach was divided into three parts: cardiac, fundic, and pyloric stomach. The epithelium of the cardiac stomach showed positive staining with PAS and weak staining with AB pH 1.0. The fundic cells showed strong positive staining with PAS but weak staining with AB pH 2.5 and pH 1.0. Whereas the cells lining the fundic and cardiac glands showed positive staining with PAS. The pyloric epithelium revealed positive staining with PAS but did not contain gland. In the anterior, middle, and posterior intestines, glands were absent. Goblet cells in each portion exhibited intense labeling with both PAS and AB pH 2.5 and pH 1.0. The intestinal coefficient was 0.62±0.01, indicating an omnivorous fish.

Pharmacognostic Investigation, Optimization of Extraction Condition and Determination of Piperine in Black Pepper Fruit

2024-05-17T09:50:19+07:00

This study aimed to investigate the standardization parameters through qualitative analyses of black pepper fruit. Microscopic characteristics of the crude drug were demonstrated. The study determined various parameters including loss on drying, total ash, acid-insoluble ash, water-soluble extractives, ethanol-soluble extractives, and volatile oil content. Additionally, piperine content in ethanol extract was evaluated using Thin Layer Chromatography (TLC) fingerprint analysis and High-Performance Liquid Chromatography (HPLC) analysis. The optimal conditions for piperine extraction were determined through experimental design. The study provides pharmacognostic specifications towards the fundamental standardization of Piper nigrum Linn. fruit.

Bacillus vietnamensis SF-1, a Promising Heterotrophic Nitrifier for Saline Wastewater Treatment

2024-06-11T13:02:33+07:00

Shrimp farming wastewater regularly contains significant quantities of organic matter and inorganic nitrogen. Additionally, shrimp are extremely toxic to inorganic nitrogen, such as nitrite and ammonia. Ammonia removal is necessary for shrimp culture to improve water quality. Heterotrophic-nitrifying bacteria, genus Bacillus, are a kind of bacteria that effectively eliminate ammonia during the nitrification and aerobic denitrification processes. In a high ammonium medium, Bacillus vietnamensis SF-1 demonstrated 69.44% ammonium removal efficiency. The production of nitrite was 0.24 mg-N/L and nitrate concentration was 0.14 mg-N/L. The suitable carbon source of B. vietnamensis SF-1 was sucrose which had ammonium removal at 57.39%, while, suitable nitrogen source was ammonium sulfate which had ammonium removal at 46.15%. C/N ratio at 8 shown higest ammonium removal of 71.15%. An optimal salinity range for strain SF-1 growth was 2.0 to 4.0% NaCl (w/v). To improve wastewater, B. vietnamensis SF-1 was added to synthesis wastewater for 14 days. The study founded that the efficacy of ammonium removal of B. vietnamensis SF-1 was 94.77%. Nitrite and nitrate increased from 0.02-0.09 and 0.01-0.27 mg-N/L, respectively. The result showed that there is considerable potential for the salt-tolerant B. vietnamensis SF-1 to improve water quality in coastal aquaculture.

Film Development of Chitosan from Mussel Shells and Pacific White Shrimp Shells

2024-05-29T12:02:30+07:00

The rapid expansion of Thailand's aquatic food processing industry has generated significant waste, prompting environmental concerns. This research aims to repurpose waste, specifically mussel and shrimp shells, to extract chitosan, a natural alternative to harmful chemicals. The primary goal is to create compostable packaging materials and preservation techniques while adding value to industry waste. The study investigated the properties of the extracted chitosan, optimized the chitosan films, and explored their use as paper coatings. The study thoroughly investigates mussel and shrimp shell-derived chitosan properties, including color value, pH, moisture, ash, and nitrogen content. Chitosan yield is 35% for mussel shells and 13.3% for shrimp shells, with a bright color and pH values of 7.32 and 7.26, respectively. Mussel shells have lower moisture (0.38%) and higher ash content (96.50%) compared to shrimp shells (4.07% moisture, 10.67% ash). Nitrogen content is 6.40% for mussel shells and 7.99% for shrimp shells. Regarding chitosan films, Method 4, a mixture of cassava starch and chitosan at a 1:0.6 ratio with 40% glycerol by weight, is identified as the optimal production method. The resulting chitosan-coated paper exhibits similar properties, making it suitable for sustainable packaging. Therefore, this research emphasizes repurposing waste from the aquatic food processing industry to promote sustainability and create livelihoods for farmers while addressing environmental challenges. Mussel shells are recommended as the primary raw material due to their larger volume and lower cost than shrimp shells. This research highlights chitosan's potential to address environmental issues and foster sustainable practices in the food processing industry.

Valorization of Agro-industrial Solid Waste by Two-stage Anaerobic Digestion for Biohythane Production

2024-05-29T13:55:50+07:00

This study investigated the valorization of agro-industrial solid waste for biohythane production through a two-stage anaerobic digestion process. Seventeen waste samples were characterized, revealing diverse physico-chemical properties suitable for anaerobic digestion. The highest biohythane yields were obtained from waste-activated sludge (WAS) from a frozen convenience food wastewater treatment plant (895.63 mL/g VS), WAS from a processed chicken wastewater treatment plant (835.73 mL/g VS), and WAS from a municipal wastewater treatment plant (830.79 mL/g VS). Kinetic analysis using the modified Gompertz model provided insights into the biohythane production potential, with predicted yields ranging from 0 to 111.85 mL/g VS and production rates from 0 to 21.37 mL/d. The comparative analysis highlighted the superior biohythane production potential of the studied waste materials compared to other substrates, such as food waste (180.5 mL/g VS) and sugarcane bagasse (165.2 mL/g VS). The highest hydrogen and methane contents in the produced biohythane were 26.57% and 67.85%, respectively. The techno-economic assessment of scaled-up biohythane production demonstrated the economic feasibility, with a payback period of 2.05 years for a plant capacity of 100 ton waste/day, a biohythane yield of 500 m³/ton waste, and a biohythane production of 50,000 m³/day. The capital cost was estimated at 15 million USD, with an operating cost of 0.2 USD/m³ biohythane and a revenue of 0.6 USD/m³ from biohythane sales. The results of this study demonstrate the high potential of agro-industrial solid waste valorization for biohythane production and its contribution to sustainable waste management and renewable energy production.