Biosurfactins production by Bacillus amyloliquefaciens R3 and their antibacterial activity against multi-drug resistant pathogenic E. coli

Abstract

In this work, the anti-Escherichia coli activity of the bioactive substances produced by Bacillus amyloliquefaciens R3 was examined. A new and cheap medium for production of the anti-E. coli substances which contained 20.0 g L(-1) soybean powder, 20.0 g L(-1) wheat flour, pH 6.0 was developed. A crude surfactant concentration of 0.48 mg mL(-1) was obtained after 27 h of 10-L fermentation, and the diameter of the clear zone on the plate seeded with the pathogenic E. coli 2# was 23.3 mm. A preliminary characterization suggested that the anti-E. coli substances produced by B. amyloliquefaciens R3 were the biosurfactins (F1, F2, F3, F4, and F5) with amino acids (GLLVDLL) and hydroxy fatty acids (of 12-15 carbons in length). It was found that all the strains of the pathogenic E. coli showed resistance to several different antibiotics, suggesting that they were the multi-drug resistance and all the strains of the pathogenic E. coli were sensitive to the biosurfactins, indicating that the biosurfactins produced by B. amyloliquefaciens R3 had a broad spectrum of antibacterial activity against the pathogenic E. coli with multi-drug resistant profiles. After the treatment with the purified biosurfactin (F1), the cell membrane of both the whole cells and protoplasts of the E. coli 2# was damaged and the whole cells of the bacterium were broken.

Isolation of bacteria from fermented food and grass carp intestine and their efficiencies in improving nutrient value of soybean meal in solid state fermentation

“…Fermented soybean meal has also been shown to improve animal performance. A previous study performed using the spores of B. amyloliquefaciens to ferment whole soybean as a target dietary supplement for use in poultry feeds was able to increase growth rate and feed efficiency by 8% and 8.8%, respectively [ 54 ]. Also, this species of bacteria has been found to have anti-bacteria activity [ 55 ] and antioxidative activity [ 46 , 55 ], which may be able to improve growth performance for weaned piglets.…”

Isolation and Characterization of Fengycins Produced by Bacillus amyloliquefaciens JFL21 and Its Broad-Spectrum Antimicrobial Potential Against Multidrug-Resistant Foodborne Pathogens

“…In recent years, many studies have shown that the cyclic lipopeptides (CLPs) produced by Bacillus spp. have potent antimicrobial activity against antibiotic-resistant strains and can be generally divided into three main families: surfactin, fengycin, and iturin (Chi et al, 2015;Jemil et al, 2017;Perez et al, 2017;Piewngam et al, 2018). Due to their specific amphiphilic structure, CLPs primarily destroy target organisms by directly disrupting the integrity of the plasma membrane or cell wall in a detergent-like manner, and thus display a lower propensity to develop resistance than do conventional antibiotics (Banat et al, 2010;Mandal et al, 2013;Singh and Abraham, 2014;Patel et al, 2015;Ndlovu et al, 2017).…”

Effects of Dietary Bacillus amyloliquefaciens SCAU-070 (Based on a Woody Plant-Based Diet) on Antioxidation, Immune and Intestinal Microbiota of Tilapia (Oreochromis niloticus)

“…In recent years, the genus Bacillus has been widely used in aquaculture [ 12 , 13 ], and it may produce a variety of secondary metabolites with antibacterial and antifungal activities, including small peptides and proteins, polyketones, and lipopeptides [ 14 , 15 , 16 ]. For example, Bacillus licheniformis and B. flexus can effectively enhance the growth, digestive enzyme activities, innate immune enzyme activities, stress tolerance, and disease resistance of Litopenaeus vannamei [ 17 ].…”