Antibacterial potency of housefly larvae extract from sewage sludge through bioconversion

作     者：Chaocheng Zheng Lixiang Zhou 

作者机构：Department of Environmental Engineering College of Resources and Environmental Science Nanjing Agricultural University 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2013年第25卷第9期

页      面：1897-1905页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 

基　　金：jointly supported by the National Natural Scientific Foundation of China (No. 21177060) The High-Tech Program (863) of China (No. 2012AA063501) the Program of Scientific Innovation Research of College Graduate in Jiangsu Province (No. CXZZ12-0273) 

主　　题：sewage sludge larvae extract anti-bacterial membrane permeability 

摘      要：Use of the fly to convert sewage sludge into nutrient-rich soil conditioner and amendment is an attractive approach for sludge bioconversion. During this process, fecal coliforms, an indicating pathogen, in sludge were reduced to 5.3 × 102 most probable number /g dry solid from initial 3.32 × 106 MPN/g dry solid. It was also found that the extract of larvae grown in sludge during bioconversion have an observable inhibitory effect against bacteria compared to larvae grown in wheat bran as measured by minimum bacterial concentration tests. In vitro antimicrobial assay tests over time also showed that the extract had strong inhibitory efficiencies of ca. 99% against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Serratia marcescens, while the efficiency was 69% and 57% against Bacillus subtilis and Klebsiella pneumoniae, respectively. The observed pathogenic bacterial cell membrane damage was found to be responsible for the phenomenon mentioned above, with nuclear acids leaching out quickly and alkaline phosphatase increasing in the outer membrane, followed by an increase of β-galactosidase in the inner membrane. Clearly, housefly larvae extract from sewage sludge through bioconversion possesses antibacterial potency against pathogenic bacteria.