Effects of organoclays on soil eubacterial community assessed by molecular approaches

Effect of formulation and repeated applications on the enantioselectivity of metalaxyl dissipation and leaching in soil

“…In addition, the supports (HT‐OLE and HT‐ELA) could have positively affected the number and/or the activity of metalaxyl‐degrading microorganisms or enzymes, for instance by stimulating microbial growth, by adsorbing the degrader microorganisms or by avoiding too high concentrations of the fungicide in the aqueous phase that could exert an adverse (toxic) effect on the soil microbial population . The interactions of organoclays with microbial growth and activity in soil are poorly documented, so that additional information is needed on this subject to gain a better understanding of the soil functioning in the presence of this kind of exogenous material …”

“…29,50 The interactions of organoclays with microbial growth and activity in soil are poorly documented, so that additional information is needed on this subject to gain a better understanding of the soil functioning in the presence of this kind of exogenous material. 48,51 Figures 4 and 5 show the breakthrough curves (BTCs) for Sand R-metalaxyl obtained in the column leaching experiment. During the experiment, rac-metalaxyl was successively applied to soil columns 3 times at a rate of 2 kg ha −1 , either as free (water-dissolved) fungicide or as the clay (HT-OLE/HT-ELA)-based formulations.…”

Modified clays alter diversity and respiration profile of microorganisms in long‐term hydrocarbon and metal co‐contaminated soil

“…Whilst changes in microbial community profiles as a result of organoclay amendments has rarely been studied (Abbate et al , ; Abbate et al , ), there is a desire to study potential ecotoxicity caused by these materials due to their potential application for remediation purposes (Lazzara et al , ). In our previous studies, the synthesized modified organoclay product (ABP) was identified as growth supportive for native heterotrophic bacteria in uncontaminated soil (Biswas et al , ) and for Mycobacterium gilvum in an aqueous suspension containing phenanthrene (Mandal et al , ).…”

“…bacteria and archaea) community profile or (ii) the ratio of respiration-active and inactive microbial groups, which resulted in the observed biodegradation outcomes. The effect of organoclays on soil microbial communities is also unclear with either stimulating or inhibitory effects depending on the type of organoclays and microorganisms assessed, for example that was reported by Abbate et al (2009). The presence of organoclays may reduce the metabolic activity of particular microbial groups, whilst stimulating the growth of others that are more adaptable to material supplements (Abbate et al, 2013).…”

Bioremediation of PAHs and VOCs: Advances in clay mineral–microbial interaction

“…The type of surfactants, their application rates and soil native characteristics (e.g., pH, moisture content, clay content, etc.) can largely govern the level of toxicity to soil microflora and fauna (Abbate et al, 2009). For example, Arquad® 2HT-75 modified bentonite is significantly less toxic than HDTMA and ODTMA modified bentonite (Sarkar et al, 2013).…”