Effect of dirhamnolipid on the removal of phenol catalyzed by laccase in aqueous solution

Abstract

In this study, the effects of three surfactants, i.e. the anionic biosurfactant dirhamnolipid (diRL), the cationic surfactant hexadecyltrimethyl ammonium bromide (CTAB), and the anionic surfactant sodium dodecyl sulfate (SDS), on the removal of phenol catalyzed by laccase were studied first. CTAB and SDS were detrimental, while diRL improved phenol removal and was selected for detailed research. The biosurfactant increased the activity of laccase and the removal of phenol with the increase of diRL concentrations from 10.6 to 318 μM. DiRL at 318 μM improved the removal when the initial concentrations of phenol were from 50 to 400 mg/l. In particular, the removal of phenol with 318 μM diRL was 4.3-6.4 folds that of the controls within 24 h when the initial concentration of phenol was 400 mg/l. The presence of diRL at 318 μM also caused the complete removal (above 98%) of phenol at concentrations from 50 to 400 mg/l after 24 h. The enhancement of phenol removal was over a wide range of pH and temperatures, and the highest removal efficiency was obtained at pH 6.0 and 50°C. The results suggest that diRL had potential application in the enhancement of phenols removal catalyzed by laccase in water treatment or remediation.

Improvement of methyl orange dye biotreatment by a novel isolated strain, Aeromonas veronii GRI, by SPB1 biosurfactant addition

“…When added at a concentration of 0.025 %, results showed a drastic decrease and a total inhibition of orange methyl decolorization by CTAB and SDS additions. These results remembered those published by Abadulla et al (2000) and Liu et al (2012) reporting dye biodecolorization inhibition by synthetic surfactants. In fact, CTAB and SDS were used to increase the solubility of methyl orange in order to increase its availability to the bacterial strain.…”

“…Raw wastewaters are highly loaded with organic matter up to several grams per liter of organic carbon that may consist of welland poorly degradable biogenic and synthetic organic compounds (such as dyes, polyphenols, pharmaceutical drugs, antibiotic, heavy metals, etc.) (Ben Mansour et al 2011a, b, 2012. Especially, textile and dye manufacturing industries are the major contribution to the disposal of toxic dyes into the water.…”

Removal of phenol and bisphenol-A catalyzed by laccase in aqueous solution

“…Majority of the fungal laccases optimally act in acidic pH [36]. In the study of Chhaya and Gupte [5], who evaluated the activity of laccase from Fusarium incarnatum UC-14 toward BPA, the pH value of 6 was introduced as optimal pH for removal of bisphenol A. study of Liu et al [37] showed that acidic environment (pH 6) was the best condition for phenol removal using the recombinant laccase of T. versicolor .…”

Modeling and Optimization of Removal of Cefalexin From Aquatic Solutions by Enzymatic Oxidation Using Experimental Design

“…In the study of Forootanfar et al (2016), it was observed that an increase in enzyme activity up to 2 U/mL increased the removal rate of stain, but an increase in enzyme activity did not have much effect on stain removal. In addition, in the study by Liu et al (2012), it was found that increased enzyme activity increases the amount of phenol removal. This is consistent with the present study.…”