PMID- 15002992
OWN - NLM
STAT- MEDLINE
DCOM- 20041102
LR  - 20181130
IS  - 1525-7797 (Print)
IS  - 1525-7797 (Linking)
VI  - 5
IP  - 2
DP  - 2004 Mar-Apr
TI  - Nanostructure of native pectin sugar acid gels visualized by atomic force 
      microscopy.
PG  - 334-41
AB  - Height and phase shift images of high methoxyl sugar acid gels (HMSAG) of pectin 
      were obtained by atomic force microscopy in the tapping mode. Images revealed 
      that pores in these gels were fluid and flattened out when measured as a function 
      of time. These images revealed for the first time the structure of adsorbed sugar 
      on pectin in the hydrated native gels and how the pectin framework is organized 
      within these gels. Segmentation of images revealed that the underlying pectin 
      framework contained combinations of rods, segmented rods, and kinked rods 
      connected end to end and laterally. The open network of strands was similar to 
      pectin aggregates from 5 mM NaCl solution imaged earlier by electron microscopy 
      (Fishman et al., Arch. Biochem. Biophys. 1992, 294, 253). Area measurements 
      revealed that the ratio of bound sugar to pectin was in excess of 100 to 1 (w/w). 
      Furthermore, images indicated relatively small differences in the organization of 
      native commercial citrus pectin, orange albedo pectin, and lime albedo pectin 
      gels at optimal pH as determined in this study. The findings are consistent with 
      earlier gel strength measurements of these gels. In addition, values of gel 
      strength were consistent with values of molar mass and viscosity of the 
      constituent pectins in that they increased in the same order. Finally, we 
      demonstrated the advantage of simultaneous visualization of height and phase 
      shift images for observing and quantitating the nanostructure of relatively soft 
      gels which are fully hydrated with a buffer.
FAU - Fishman, Marshall L
AU  - Fishman ML
AD  - Crop Conversion Science and Engineering Research Unit, Eastern Regional Research 
      Center, Agricultural Research Service, US Department of Agriculture, Wyndmoor, 
      Pennsylvania 19038, USA. mfishman@errc.ars.usda.gov
FAU - Cooke, Peter H
AU  - Cooke PH
FAU - Coffin, David R
AU  - Coffin DR
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PL  - United States
TA  - Biomacromolecules
JT  - Biomacromolecules
JID - 100892849
RN  - 0 (Gels)
RN  - 0 (Plant Extracts)
RN  - 0 (Sugar Acids)
RN  - 89NA02M4RX (Pectins)
SB  - IM
MH  - Citrus aurantiifolia/chemistry/ultrastructure
MH  - Citrus sinensis/chemistry/ultrastructure
MH  - Gels
MH  - Microscopy, Atomic Force/*methods
MH  - Nanotechnology/*methods
MH  - Pectins/*chemistry/isolation & purification/ultrastructure
MH  - Plant Extracts/chemistry/isolation & purification
MH  - Sugar Acids/*chemistry/isolation & purification
EDAT- 2004/03/09 05:00
MHDA- 2004/11/04 09:00
CRDT- 2004/03/09 05:00
PHST- 2004/03/09 05:00 [pubmed]
PHST- 2004/11/04 09:00 [medline]
PHST- 2004/03/09 05:00 [entrez]
AID - 10.1021/bm0300655 [doi]
PST - ppublish
SO  - Biomacromolecules. 2004 Mar-Apr;5(2):334-41. doi: 10.1021/bm0300655.