Enhanced control of sulfonamide resistance genes and host bacteria during thermophilic aerobic composting of cow manure. (15th April 2021)

• Record Type: Journal Article
• Authors: Sardar, Muhammad Fahad; Zhu, Changxiong; Geng, Bing; Huang, Yali; Abbasi, Bilawal; Zhang, Zhiguo; Song, Tingting; Li, Hongna
• Is Part Of: Environmental pollution. Volume 275(2021)
• Publication Date: 2021-04-15
• Subjects: Thermophilic temperature -- Sulfamethoxazole -- Sulfonamide resistance genes -- Rebounding -- Potential carriers; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.116587
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Traditional composting has already shown a certain effect in eliminating antibiotic residues, antibiotic-resistant bacteria (ARBs), and antibiotic resistance genes (ARGs). It is worth noting that the rebounding of ARGs and the succession of the bacterial community during conventional aerobic composting are still serious threats. Considering the probable risk, improved and adaptable technologies are urgently needed to control antibiotic resistance efficiently. This study monitored how thermophilic aerobic composting affected the ARGs, as well as the bacterial diversity during the composting of cow manure spiked with sulfamethoxazole (SMX) at different concentrations. Results showed that the degradation of SMX was enhanced during thermophilic aerobic composting (control > SMX25 > SMX50 > SMX100) and was no longer detected after 20 days of composting. High temperature or heat significantly stimulated the rebounding of certain genes. After 35 days, the abundance of detected genes ( sul2, sulA, dfrA7, and dfrA1 ) significantly decreased ( p < 0.05 ) in control and antibiotic-spiked treatments, except for sul1 . The addition of three concentrations of SMX elicited a sharp effect on bacterial diversity, and microbial structure in SMX25 led to significant differences with others ( p < 0.05 ). The network analysis revealed more rigorous interactions among ARGs and abundant genera, suggesting that the host of ARGs potentially increased at low concentrations of SMX. Especially, genera g_norank_f__Beggiatoaceae, Ruminiclostridium, Caldicoprobacter, g_norank_o_MBA03, Hydrogenispora, and Ruminiclostridium_1 were major potential hosts for sul1 . In conclusion, the rebounding of ARGs could be intermitted partially, and more efficient control of antibiotic resistance could be achieved in the thermophilic composting compared to conventional methods. Graphical abstract: Image 1 Highlights: The abundance of detected genes ( sul2, sulA, dfrA7 and dfrA1 ) significantly decreased. Primary microbial composition sustained and carriers of ARGs increased in SMX 25. Artificially induced thermophilic composting efficiently reduced ARGs rebounding. Ruminiclostridium, Caldicoprobacter and Hydrogenispora were carriers for sul1. Abstract : The artificially induced thermophilic temperature during aerobic composting of cow manure efficiently reduced the risk of rebounding of ARGs.