KARAKTERISASI FTIR DAN AKTIVITAS ANTI BAKTERI NANOCHITO (CHITOSAN/MgO/AC) BERBASIS SHRIMP SHELL DAN COCONUT CARBON SEBAGAI INOVASI TOXIC METABOLITES REMOVER LIMBAH TAMBAK UDANG

Intensive shrimp aquaculture plays a significant role in national economic growth but generates wastewater rich in nitrogen, phosphorus, and pathogenic bacteria, causing serious environmental impacts on coastal ecosystems. This study aimed to develop and evaluate NanoChito, a nanocomposite based on chitosan derived from shrimp shells, magnesium oxide (MgO), and activated carbon from coconut shells, as an environmentally friendly innovation for shrimp pond wastewater treatment. Material characterization was conducted using Fourier Transform Infrared Spectroscopy (FTIR) to identify functional groups, while antibacterial activity was assessed using the disc diffusion method against pathogenic bacteria. FTIR analysis revealed characteristic absorption bands of Mg–O at 624 cm⁻¹, aromatic C–H at 873 cm⁻¹, and C–O–C, C–N, and C–O vibrations within the range of 1037–1261 cm⁻¹, confirming the successful formation of the chitosan/MgO/activated carbon nanocomposite. A broad band at 3697 cm⁻¹ indicated the presence of hydroxyl (–OH) groups, suggesting hydrogen bonding interactions among the composite components that contribute to material stability. Antibacterial testing showed that NanoChito exhibited an inhibition zone of 11.87 mm, higher than that of chitosan alone (8.37 mm) and activated carbon (7.24 mm), although lower than the positive control ampicillin (17.02 mm). These results indicate a synergistic effect among chitosan, MgO, and activated carbon in enhancing antibacterial activity. Overall, NanoChito demonstrates strong potential as an effective, sustainable, and eco-friendly material for controlling toxic metabolites and pathogenic bacteria in shrimp pond wastewater.