Endoglucanase enzymatic modification of kraft pulp during recycling.

Abstract

OBJECTIVE:

To investigate the cellulose modification process on kraft pulp during recycling by mono-endoglucanase.

RESULTS:

Pichia pastoris expressing endoglucanase, EG1, was grown in a 10 l fermenter yielding a high carboxymethyl cellulase (CMCase) activity of 340 U mg(-1). EG1-mediated modification of kraft pulp resulted in a paper sheet with the tensile index and burst index increased by 10 and 6.5 %, respectively. The kink index (indicating abrupt bends in fibres) of the enzyme-treated group decreased sharply by 45 % after the first recycling, compared with a reduction of only 1 % in the control group. Furthermore, EG1 treatment decreased the growth of crystallinity from 73.5 to 73.2 % and crystal size from 7.45 to 7.21 nm, which alleviated paper aging.

CONCLUSION:

Endoglucanase EG1 modifies the interfacial properties of fibers, which affects fibre morphology during the recycling process and improves the technical properties of the resulting pulp and paper.

• Authors: Tao Deng, Liuliu Lu, Shipeng Gao, Ying Lin, Shuangyan Han
• Journal: Biotechnology letters (Biotechnol Lett) Vol. 38 Issue 7 Pg. 1139-45 (Jul 2016) ISSN: 1573-6776 [Electronic] Netherlands
• PMID: 27060009 (Publication Type: Journal Article)

Chemical References

• Cellulase
• carboxymethylcellulase

Topics

• Cellulase (metabolism)
• Paper
• Pichia (enzymology)