Interactive Effects of pH and Temperature on Cell Growth and Polymer Production by Xanthomonas campestris

Optimisation of xanthan gum production by palm date (Phoenix dactylifera L.) juice by-products using response surface methodology

“…It is associated with the activation of enzymes that act in the polymerisation process of xanthan. These results are in agreement with other previously reported findings in the literature (Esgalhado, Roseiro, & Amaral, 1995) showing that the carbon source has a positive effect on xanthan production, which also increases upon decreasing temperature.…”

“…Similarly, Esgalhado et al (1995) previously referred to an optimum temperature ranging from 30 to 32°C.…”

Production, recovery and applications of xanthan gum by Xanthomonas campestris

“…Psomas et al (2007) observed that the pH values of the broth after 24 h fermentation were ranged from 7 to 8, after 48 h fermentation broth from 8 to 9.5 and after 72 h fermentation from 8 to 10 depending on the chosen combination of agitation and temperature. Esgalhado et al (1995) showed that the optimum pH for culture growth was 6-7.5 and optimum pH for the xanthan production was 7-8. Garcia-Ochoa et al (1996) suggested that the Xanthomonas can be cultured at a neutral pH.…”

“…In addition, Yang (1990, 1991) concluded that the optimal temperature for xanthan production depended on the production medium used. Esgalhado et al (1995) reported that the optimal temperature for X. campestris growth was 25-27°C and optimal temperature for xanthan gum production was 25-30°C. Xanthan presents a confirmational transition depending upon a temperature (Milas and Rinaudo, 1979;Morris et al, 1977).…”

Tourmaline ceramic balls stimulate growth and metabolism of three fermentation microorganisms

“…However, medium carbohydrate was decreased by 83% over the controls, while the change of medium pH value, as a result of production of organic acids, was relatively less, being only 0.3 lower than its control. It was reported that tourmaline had a function of self-control and stabilization of pH value and intended to maintain or shift to an alkaline environment (Esgalhado et al 1995;Yoshitake et al 1996;Ji et al 2002;Xia et al 2006). Based on this, it was considered that the change of medium pH in tourmaline treatment in L. acidophilus might not reflect the real level of the increased production of organic acids.…”