fulltext.study @t Gmail

Studies on intracellular degradation of polyhydroxyalkanoic acid–polyethylene glycol copolymer accumulated by Azotobacter chroococcum MAL-201

Paper ID Volume ID Publish Year Pages File Format Full-Text
24908 43544 2007 6 PDF Available
Title
Studies on intracellular degradation of polyhydroxyalkanoic acid–polyethylene glycol copolymer accumulated by Azotobacter chroococcum MAL-201
Abstract

Azotobacter chroococcum MAL-201 accumulates poly(3-hydroxybutyric acid) [PHB] when grown in glucose containing nitrogen-free Stockdale medium. The same medium supplemented with valerate alone and valerate plus polyethylene glycol (PEG) leads to the accumulation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [PHBV] and PEG containing PHBV–PEG polymers, respectively. The intracellular degradation of these polymers as studied in carbon-free Stockdale medium showed a rapid degradation of PHB followed by PHBV, while it was least in case of PHBV–PEG. The rate of such degradation was 44.16, 26.4 and 17.0 mg h−1 l−1 for PHB, PHBV and PHBV–PEG, respectively. During the course of such of PHBV and PHBV–PEG degradation the 3HB mol% of polymers decreased significantly with increase of 3HV mol fraction, the EG mol% in PHBV–PEG, however, remained constant. After 50 h of degradation the decrease in intrinsic viscosity and molecular mass of PHBV–PEG were 37.5 and 43.6%, respectively. These values appeared low compared to PHB and PHBV. Moreover, the increasing EG content of polymer retarded their extent of degradation. Presence of PEG, particularly of low molecular weight PEG was inhibitory to intracellular PHA depolymerise (i-PHA depolymerase) activity and the relative substrate specificity of the i-PHA depolymerase of MAL-201 appeared to be PHB > PHBV > PHBV–PEG.

Keywords
Polyhydroxyalkanoic acid; Poly(3-hydroxybutyric acid); Poly(3-hydroxybutyrate-co-3-hydroxyvalerate); Polyethylene glycol; PHBV–PEG copolymer; Intracellular PHA degradation
First Page Preview
Studies on intracellular degradation of polyhydroxyalkanoic acid–polyethylene glycol copolymer accumulated by Azotobacter chroococcum MAL-201
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Journal of Biotechnology - Volume 132, Issue 3, 1 November 2007, Pages 325–330
Authors
, , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us