Concentration-Dependent Antimicrobial Activity of Neem and Bitter Gourd Extracts: A Sustainable Approach to Mitigate Pollution in Dhaka

Abstract

Air pollution in Dhaka city is increasingly severe, surpassing levels observed in many comparable urban areas. As lifestyle and dietary patterns shift, the selection of health-promoting vegetables and natural food components has become particularly important. Bitter gourd and neem extracts possess well documented antibacterial properties and are associated with improved liver and kidney function. Chronic exposure to polluted air heightens the risk of respiratory complications, a vulnerability further intensified by smoking. Therefore, avoiding tobacco use and incorporating natural protective foods into the daily diet may help strengthen immunity and mitigate the adverse health effects of rising air pollution.Aqueous leaf extracts of Azadirachta indica (neem) and Momordica charantia (bitter gourd) were tested against road dust particles collected from Dhaka city. Both extracts showed strong antimicrobial and antifungal activity and Gram staining confirmed the presence of mixed microbial species in Dhaka air pollution. A biochemical study involving 20 people from Rajshahi and 20 long term Dhaka residents indicted that the extract alone or combined, may help improve kidney, liver and lipid parameters. Chest X rays of six Dhaka residents also showed signs of respiratory effects linked to polluted air. These findings highlight the antimicrobial potential of the extracts and health risks associated with microbially contaminated urban air. The aim of this study is to evaluate the antibacterial and antifungal activities of aqueous extracts of Azadirachta indica (neem) and Momordica charantia (bitter gourd) and to assess their potential as dietary options for people in living Dhaka city to help counter pollution related health effects and support lung, liver and kidney function.