[P004] Poster

1:00 PM - 1:50 PM JST(4:00 AM - 4:50 AM UTC)

[P02-208] Co-Fermented Microalgal Residues as a Multifunctional Bio-Amendment for Sustainable Cherry Tomato Production: Implications for Circular Bioeconomy and Carbon Footprint Reduction

○Hsien-Yin Huang¹, Wei-Chun Chen², Chun-Yen Chen¹ (1. University Center for Bioscience and Biotechnology, NCKU, Tainan, Taiwan (Taiwan), 2. Tainan Tzu-Chi High School, Tainan, Taiwan (Taiwan))

Keywords:

Environmental biotechnology,Sustainable agriculture,Circular nutrient utilization,Climate-smart agriculture,Organic waste valorization

The sustainable aviation fuel (SAF) industry generates large quantities of microalgal residues after lipid extraction. Reutilization of these nutrient-rich by-products offers a promising pathway to reduce environmental burdens while supporting sustainable agriculture. The residues contained 51.5% protein as an organic nitrogen source, 19.38% carbohydrates mainly in the form of polysaccharides and cellulose providing slow-release carbon, and 3.17% mineral-rich ash supplying essential nutrients. This study evaluated the co-fermentation of microalgal residues with Bacillus licheniformis and the application of the resulting fermentation broth in cherry tomato cultivation. Field application using a 150-fold dilution replaced more than 72.3% of chemical fertilizers while maintaining healthy plant growth. Treated plants showed a 15.32% increase in yield, and fruit soluble solids reached 8.4 °Brix, indicating improved sweetness and market quality. Leaf chlorophyll content remained stable (SPAD 54), suggesting efficient nitrogen utilization under reduced fertilizer input. Soil health improved significantly, with soil organic matter increasing to 2.6%, pH rising from 6.2 to 6.7, and electrical conductivity increasing from 0.10 to 0.24 dS/m, indicating enhanced fertility, buffering capacity, and nutrient availability. The substantial reduction in synthetic fertilizer use implies lower carbon emissions and decreased risk of nutrient runoff. Overall, co-fermented microalgal residues function as a multifunctional bio-amendment that enhances crop productivity, improves soil health, and supports circular bioeconomy development. This approach provides a sustainable and climate-smart strategy for integrating biofuel by-product valorization with environmentally responsible agricultural production.