Global Journal of Medical Research, K: Interdisciplinary, Volume 22 Issue 3

Dispersion of Multidrug Resistant Bacteria and Fecal Bacteria into Field Soils of Japan through Compost Application Dispersion of Hazardous Bacteria Katsuji Watanabe Abstract- As huge amount of organic fertilizer of fecal origin has annually been dispersed into field soils without checking included hazardous bacteria. In order to estimate their contamination level in Japanese field soils, MRB and fecal bacteria in nine composts, which had originated from cattle feces, pig feces, and chicken droppings andbeen applied on soils for organic farms in various regions of Japan, were evaluated by using an originally developed analysis method. The tested composts included higher number of general bacteria (from 7.08x109 MNP g-1 dry matter to 316.2x109 MNP g-1), where gram-positive bacterial groups, such as Actinobacteria, Bacillus sp., and Staphylococcus sp., and the other Firmicutes were the numerical dominant in most of them (22% to 98%). Six out of nine composts included over the detection limit of MRB, which proliferated under mixture of 25ppm each of streptomycin, chloramphenicol, and ampicillin(1x104 MPN g-1 dry matter to 84.9x104 MPN g-1), where gram-negative MBR were the numerically dominant(33.3% to 100%). As most of the composts included not only fecal bacteria and pathogenic bacteria but also MRB of fecal origin such as Bacteroides sp., B.coprocola, and Borrelia recurrent, large area of Japanese field soils were suggested to be contaminated with such the fecal bacteria through application of compost. Correlation analyses of each bacterial numbers suggested that most of MRBmight had survived against the thermophilic phase in the composting process and could had been eliminated by regulating thermophilic phase. Core ideas • Higher ratio of composts for organic farmers included multidrug resistant bacteria (MRB). • Higher ratio of composts for organic farmers included fecal bacteria and pathogenic bacteria. • Numbers of MRB and thermotolerant bacteria in composts varied in reverse trend. • MRB in composts might be eliminated by controlling an abiotic factor. • The used method was effective to evaluate MRB and fecal bacteria in compost. Author: Department of Life, Environment and Applied Chemistry, Graduate School of Engineering, Fukuoka Institute of Technology, Japan. e-mail: k-watanabe@fit.ac.jp I. I ntroduction t present, almost all farmers have been encouraged to spread organic fertilizer into field soil under a government policy to improve soil fertility and maintain field conditions (FAO 2018; Rayne and Aula 2020). The spreading of organic fertilizer into field soils has also been encouraged to reduce and to recycle organic wastes under social demand to construct sustainable societies in all over the world (Chatterjee et al., 2017, Sharma et al.,2019). As organic fertilizer originates from raw livestock feces which includes pathogenic bacteria (Gerba & Smith 2005) or multidrug resistant bacteria (MRB) (Agga et al., 2015; Loofta et al., 2012), organic fertilizer application has a possibility to enhance contamination of such the hazardous bacteria to various environments (Smith et al.,2019; Watanabe 2008, 2009;Watanabe et al.,2008; Watanabe and Koga 2009; Watanabe et al., 2015a) and foods (Hölzel et al., 2018; Marti et al., 2013; Zekar et al., 2017; Zhang et al., 2019). Although fecal bacteria might be reduced during composting process, huge amount of organic fertilizer, which is made from livestock feces by various ways and includes various amount of such the hazardous bacteria, has annually been dispersed onto field soils without checking. In order to reduce their contamination to various environments and food, an appropriate method to check such hazardous bacteria in organic fertilizer is required before their application on field soil (Watanabe 2008, 2009; Watanabe et al., 2008; Watanabe and Koga 2009). Whereas with respect to MBR, conventional surveillance method targeting specific nosocomial bacteria was not suitable, because the susceptibility tests and taxonomy determinations of isolates should be expanded broadly over various kinds of bacterial groups (Burgos et al., 2005; DebMandal et al., 2011; Ghosh. & LaPara 2007; Kilonzo-Nthenge et al., 2013; Oliver et al., 2020; Sawant et al., 2007, Yang et al., 2016; Young quist et al., 2016). Furthermore, un-culture-based molecular methods such as quantitative polymerase chain reaction (qPCR) and next generation sequencing (NGS) was also not suitable. Because the antibiotic resistant genes (ARGs) targeted by these methods were not intrinsic A 19 Year 2022 Global Journal of Medical Research Volume XXII Issue III Version I ( D ) K © 2022 Global Journals