Pycnoporus cinnabarinus laccases: an interesting tool for food or non-food applications.
The effects of the addition of ferulic acid and ethanol in P. cinnabarinus ss3 culture medium in fermentor were compared in 15-L fermentor. In the presence of 30 g l(-1) ethanol, laccase activity (270,000 U/L1) was 3-fold higher as compared with ferulic acid-induced cultures, and 150-fold higher as compared with non-induced cultures, respectively. High-quality flax pulp was bleached in a totally-chlorine free (TCF) sequence using a laccase-mediator system constituted by laccase from Pycnoporus cinnabarinus and 1-hydroxybenzotriazole (HBT) as mediator. Up to 90% delignification and strong brightness increase were attained after the laccase-mediator treatment followed by H2O2 bleaching. This TCF sequence was further improved by applying H2O2 under pressurized O2. In this way, up to 82% ISO brightness was obtained (compared with 37% in the initial pulp and 60% in the peroxide-bleached control) as well as very low kappa number. A positive evaluation of the laccase has been also performed in a food application. The colour of a tea-based beverage was significantly improved by incubating an infusion of green tea with the Pycnoporus laccase.
Beldem S.A., Puratos Group, Rue Bourrie 12, ZI de Seilles, B-5300 Andenne, Belgium.
J
J
Georis
A
A
Lomascolo
S
S
Camarero
V
V
Dorgeo
I
I
Herpoël
M
M
Asther
A T
AT
Martinez
T
T
Dauvrin
D003373:Coumaric Acids / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation; D005505:Food Coloring Agents; D007700:Kinetics; D042845:Laccase / Q000378:metabolism*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D010636:Phenols / Q000378:metabolism; D011124:Polyporaceae / Q000201:enzymology* / Q000254:growth & development; D013662:Tea
D003373:Coumaric Acids; D005505:Food Coloring Agents; D010636:Phenols; D013662:Tea; D000431:Ethanol; C004999:ferulic acid; D042845:Laccase