Characterization of Clostridium Perfringens Isolates Collected from Three Agricultural Biogas Plants over a One-Year Period

Abstract

Digestate produced by agricultural biogas plants (BGPs) may contain pathogenic bacteria. Among them, Clostridium perfringens deserves particular attention due to its ability to grow under anaerobic conditions and persist in amended soil. The aim of this study was to examine the potential pathogenicity and the antimicrobial resistance of C. perfringens in manure and digestate collected from three agricultural biogas plants (BGPs). A total of 157 isolates (92 from manure, 65 from digestate) were screened for genes encoding seven toxins (cpa, cpb, etx, iapcpe, netB, and cpb2). The 138 cpa positive isolates were then screened for tetA(P), tetB(P), tet(M), and erm(Q) genes and tested for antimicrobial susceptibility. The toxinotypes identified in both manure and digestate were type A (78.3% of the isolates), type G (16.7%), type C (3.6%), and type D (1.4%), whereas none of the isolates were type F. Moreover, half of the isolates carried the cpb2 gene. The overall prevalence of tetA(P) gene alone, tetA(P)-tetB(P) genes, and erm(Q) gene was 31.9, 34.8, and 6.5%, respectively. None of the isolates harbored the tet(M) gene. Multiple antimicrobial resistant isolates were found in samples that were collected from all the manure and digestates. Among them, 12.3% were highly resistant to some of the antibiotics tested, especially to clindamycin (MIC ≥ 16 µg/mL) and tilmicosin (MIC > 64 µg/mL). Some isolates were highly resistant to antibiotics used in human medicine, including vancomycin (MIC > 8 µg/mL) and imipenem (MIC > 64 µg/mL). These results suggest that digestate may be a carrier of the virulent and multidrug resistant C. perfringens.

Chlorogenic acid protects against intestinal inflammation and injury by inactivating the mtDNA–cGAS–STING signaling pathway in broilers under necrotic enteritis challenge

“…Currently, some antibiotics are allowed for treating NE in poultry production. However, the improper use of antibiotics results in drug resistance in C. perfringens and increases public concerns regarding residual drugs in animal products ( Derongs et al, 2020 ). This situation underscores an urgent need for a natural alternative in poultry production ( Lu et al, 2022 ).…”

Prevalence and Genetic Diversity of Clostridium perfringens Isolates in Hospitalized Diarrheal Patients from Central China

“…7,8 Apart from CPE, beta2 toxin encoded by the cpb2 gene has been associated with enteric disease in humans and necrotic enteritis in chickens and many other animal species. 7,9,10 A recent study suggested that beta2 toxin was significantly associated with children suffering from autism spectrum disorders (ASD). 11 Multi-locus sequence typing (MLST) is a commonly used technique for the typing of human, animal and foodborne pathogens.…”

Effect of the Inoculum-to-Substrate Ratio on Putative Pathogens and Microbial Kinetics during the Batch Anaerobic Digestion of Simulated Food Waste

“…Although Clostridium species are acclimatised to biogas environments [ 10 , 34 , 35 , 36 ] and are known to be involved in the hydrolytic and acidogenic stages of the AD process [ 4 ], ISRs 0.25 and 0.50 achieved 2 log 10 and 1.5 log 10 decrease in counts, respectively. This also agrees with the work of Fontana et al [ 21 ], who observed a slight decrease in the number of culturable Clostridium spores in the digestate compared with the inoculum during continuous mesophilic AD.…”