Bioactivity of a Novel Glycolipid Produced by a Halophilic Buttiauxella sp. and Improving Submerged Fermentation Using a Response Surface Method

Abstract

An antimicrobial glycolipid biosurfactant (GBS), extracted and identified from a marine bacterium, was studied to inhibit pathogenic microorganisms. Production of the GBS was optimized using a statistical method, a response surface method (RSM) with a central composite design (CCD) for obtaining maximum yields on a cost-effective substrate, molasses. The GBS-producing bacterium was identified as Buttiauxella Species in terms of biochemical and molecular characteristics. This compound showed a desirable antimicrobial activity against some pathogens such as E. coli, Bacillus subtilis, Bacillus cereus, Candida albicans, Aspergilus niger, Salmonella enterica. The rheological studies described the stability of the GBS at high values in a range of pH (7-8), temperature (20-60) and salinity (0%-3%). The statistical optimization of GBS fermentation was found to be pH 7, temperature 33 • C, Peptone 1%, NaCl 1% and molasses 1%. The potency of the GBS as an effective antimicrobial agent provides evidence for its use against food and human pathogens. Moreover, favorable production of the GBS in the presence of molasses as a cheap substrate and the feasibility of pilot scale fermentation using an RSM method could expand its uses in food, pharmaceutical products and oil industries.

Evaluation of antimicrobial activity of synthesised silver nanoparticles using Thymus kotschyanus aqueous extract

“…As shown in Fig. 4 a , which presents the FTIR spectrum of crude extract, a broad signal was observed about 3377 cm −1 can be attributed to O–H or C–N stretching vibration modes in primary amines of aromatic compounds [22]. The others peaks, 2941.54, 1452.09 and 669.32 cm −1 observed can be associated with C–H bond in alcohols and phenols, carbonyl present in the plant extract.…”

Recovery of Biosurfactant Using Different Extraction Solvent by Rhizospheric Bacteria Isolated from Rice-husk and Poultry Waste Biochar Amended Soil

“…This test was chosen because it is accurate, quick, reliable and easy to carry out compared to the surface tension measurement which is time consuming and tedious which makes it inconvenient to screen large number of isolates [51]. The findings of the emulsification activity disagrees with the work of [52] who reported lower values of 54.8% which could be as a result of the alterations of the pH, temperature and salinity of the medium. This work, however agrees with the report of some researchers such as [49,53] who have also reported Pseudomonas sp.…”

Marine Biosurfactants: Biosynthesis, Structural Diversity and Biotechnological Applications

“…and a coral isolate identified as Serratia marcescens. Here, glucose moieties are esterified with middle and long chain length fatty acids (C14 to C18), respectively, to form, for example, glycosyl palmitate ( 7 ) [95,96]. For proteobacterial glycolipids, ester-linked fatty acids are very uncommon.…”