Effects of Nonionic Surfactants on Xanthan Gum Production: a Survey on Cellular Interactions

Abstract

BackgroundXanthomonas campestris is a biopolymer producing gram negative bacterium. Production of xanthan biopolymer can be affected by different extrinsic factors as well as surfactants. Hitherto, effects of nonionic surfactants on xanthan production have been studied in a limited number of articles.ObjectiveIn the present study, nonionic surfactants were used to pursue their effects on improvement of xanthan production. Moreover, a number of cellular consequences upon the treatment were investigated with impacts on gum production.Materials and MethodsEffects of different nonionic surfactants (Tween 20, Tween 80 and Triton X100) on xanthan production and Xanthomonas campestris cells were assessed by ultramicroscopy (SEM), changes in culture turbidity, leakage of sugars and ATP, and quality of xanthan (i.e. pyruvate content and determination of polymer molecular weight).ResultsThe nonionic surfactant Tween 20 increased ATP (3.2 folds) and sugar leakage (3.1 folds). Furthermore, they caused cell shape alteration. Tween 80 improved both xanthan production (11 g.L-1) and viscosity of the product (1368 cP), while the total biomass remained unchanged (2.2 g.L-1). Molecular weight of xanthan was enhanced (from 23 to 59 million Da). Toxic effect of 5% (v/v) Triton X 100 decreased the turbidity of culture to 120 NTU and total biomass was diminished to 1 g.L-1. Tween 20 caused the loss of ATP and sugar leakage and led to lower xanthan production. It had no effect on biomass content.ConclusionsIn general, amounts of surfactants that bacterial cells can tolerate seem to be helpful in substrate and metabolite transportation, and enzyme activities involved in xanthan biosynthesis and release. Surfactants induce harsh damages to cell barriers, preventing the growth and adversely affecting quantity and quality of xanthan gum.

Inhibiting Desertification Using Aquatic Cyanobacteria Assisted by a Nanocomposite

“…The mass loss (12.61%) between 100.9 and 441.9 °C corresponded to the removal of −OH 2 of ATP and the decomposition of SP into acrylic acid. 34 The mass loss (15.46%) between 441.9 and 507.5 °C was ascribed to the pyrolysis of the acrylic acid. 33 The mass loss (8.35%) between 507.5 and 807.5 °C probably originated from the pyrolysis of XG.…”

“…33 The mass loss (8.35%) between 507.5 and 807.5 °C probably originated from the pyrolysis of XG. 34,35 Generally, the temperature in deserts is below 100 °C. SXA was demonstrated to have high thermal stability and can be used in deserts.…”

“…As shown in Figure C, the mass loss (6.59%) between 13.8 and 100.9 °C was attributed to the removal of free water. The mass loss (12.61%) between 100.9 and 441.9 °C corresponded to the removal of −OH 2 of ATP and the decomposition of SP into acrylic acid . The mass loss (15.46%) between 441.9 and 507.5 °C was ascribed to the pyrolysis of the acrylic acid .…”

Origanum vulgare Terpenoids Induce Oxidative Stress and Reduce the Feeding Activity of Spodoptera littoralis

“…However, the contrasting results between the modulation exerted by feeding on leaves does not exclude the possibility that the regulation of this genes could be associated to other O. vulgare constituents such as phenolics [ 64 , 65 , 66 ]. It is known that some surfactants may interfere with enzyme activities [ 67 ]. Interestingly, the use of Tween-20 (which was essential for terpenoid solubilization) affected the enzyme activities of all tested enzymes.…”

The biotechnological production of xanthan on vegetable oil industry wastewaters (part II): Kinetic modelling and process simulation

“…With the goal of reducing production costs and increasing the competitiveness of xanthan on the market, it is necessary to improve the productivity of the process by developing a more efficient production process, optimizing cultivation media content or isolating new strains of X. campestris which have better production capabilities in the given experimental conditions [31]. Since the improvement of the amount of the desired product can be realized by using a suitable cultivation media for its production, it is significant to choose and optimize cultivation media content regarding the most important micro and macronutrients for its production [13,[32][33][34][35]. Additionally, it is important to choose and optimize suitable process parameters such as agitation, aeration rate, cultivation time and bioreactor geometry [36][37][38].…”