Air contamination in confined environments can lead to severe health damage. Searching for effective and sustainable technologies that might bring quality to indoor air is necessary. Heterogeneous photocatalysis has been studied for its ability to oxidize, inactivating microorganisms in the air. In the present work, a reactor was assembled, where titanium dioxide (TiO2) P25 was incorporated into the inner face of polyvinyl chloride (PVC) tubes and vegetable sponges (Luffa sp.). Polyester Orthophthalic (PO) resin was used to fix the TiO2 onto the surfaces. Ultraviolet lamps (UVA) were used to activate the TiO2 catalyst to test the inactivation capacity of microorganisms, as they are economical and present high energy efficiency and long service life. The inactivation of microorganisms was evaluated in natural and artificially contaminated atmospheres. The photocatalytic reactor proved efficient in most tests in both atmospheres. In tests 1 and 2, no bacterial colony-forming units (CFUs) were found in the photocatalysis tube. In test 3, the average of 5 CFUs of fungi in the photocatalysis tube and 12.67 in the control tube was found, indicating inactivation. Therefore, this research is essential for presenting an alternative solution for indoor air treatment.