Bacillus subtilis extracellular polymeric substances conditioning layers inhibit Escherichia coli adhesion to silicon surfaces: A potential candidate for interfacial antifouling additives

Abstract

Biofouling on material surfaces is a ubiquitous problem in a variety of fields. In aqueous environments, the process of biofouling initiates with the formation of a layer of macromolecules called the conditioning layer on the solid-liquid interface, followed by the adhesion and colonization of planktonic bacteria and the subsequent biofilm development and maturation. In this study, the extracellular polymeric substances (EPS) secreted by Bacillus subtilis were collected and used to prepare conditioning layers on inert surfaces. The morphologies and antifouling performances of the EPS conditioning layers were investigated. It was found that the initial adhesion of Escherichia coli was inhibited on the surfaces precoated with EPS conditioning layers. To further explore the underlying antifouling mechanisms of the EPS conditioning layers, the respective roles of two constituents of B. subtilis EPS (γ-polyglutamic acid and surfactin) were investigated. This study has provided the possibility of developing a novel interfacial antifouling additive with the advantages of easy preparation, nontoxicity, and environmental friendliness.

ESKAPEE Pathogen Biofilm Control on Surfaces with Probiotic Lactobacillaceae and Bacillus species

“…Lactobacillus agilis [122], Lactobacillus caucasicus [19], Lactobacillus gallinarum [31], Lactobacillus gastricus [90], Lactobacillus johnsonii [24], Lactobacillus kunkeei [123], Lactobacillus murinus [124], Latilactobacillus sakei [102], Lactobacillus vaginalis [106] and Lacticaseibacillus zeae [58] were each only reported once. Among Bacilli, Bacillus subtilis was the most frequently reported species (five times) [125][126][127][128][129], followed by Bacillus velezensis (two times) [130,131]. Bacillus thuringiensis [46], Bacillus amyloliquefaciens [126], Bacillus cereus [132] and Bacillus pumilus [133] were each reported once.…”

“…The latter included Caco-2 [44,50,89,103], HT29 [24,89,101], HeLa 229 [65,83], vaginal epithelial cells [71], and uroepithelial cells [143]. Some of the in vitro experiments tested the antibiofilm properties of the probiotic bacteria on inert surfaces [81,93,125], most importantly on metals such as stainless steel [120] or titanium [28]. Other surfaces included those made of silicon [32], ceramics, and linoleum [144].…”

“…Nine reports described pathogen inhibition to be caused by direct competition between probiotic and pathogenic bacterial cells [24,29,32,40,102,108,135,143,148]. Nineteen studies pinned the bactericidal properties down on one or more specific cell products [46,49,51,56,57,59,73,76,99,100,117,125,127,129,133,136,[149][150][151]. Eleven studies ascribed the suppression of pathogens to be attributable to both, direct competition and cell products [27,55,61,64,72,75,77,104,116,126,152].…”

The Application of Bacillus subtilis for Adhesion Inhibition of Pseudomonas and Preservation of Fresh Fish

“…in the supplemented feed group decreased after eight days of storage (Figure 4). Therefore, B. subtilis plays an important role in inhibiting the initial adhesion, growth, and reproduction of spoilage bacteria, as well as in maintaining the balance of intestinal flora in fish [30].…”