Improvement of formaldehyde-scavenging ability of condensed tannins by ammonia treatment

Holzforschung ◽  
2006 ◽  
Vol 60 (2) ◽  
pp. 178-183 ◽  
Author(s):  
Koh Hashida ◽  
Seiji Ohara ◽  
Rei Makino
Keyword(s):  
Condensed Tannins ◽  
Type A ◽  
High Ratio ◽  
Gas Chromatography Mass Spectrometry ◽  
Type B ◽  
Ammonia Treatment ◽  
Pyrolysis Gas ◽  
Factors Affecting ◽  
Line Methylation ◽  
On Line

Abstract Condensed tannins have formaldehyde gas-scavenging ability. Tannins consisting of phloroglucinol-type A-rings, such as prodelphinidin and procyanidin, had higher formaldehyde-scavenging ability than those consisting of resorcinol-type A-rings, such as prorobietinidin and profisetinidin. This ability was markedly improved by ammonia treatment. The increase in formaldehyde-scavenging ability was especially notable in the case of condensed tannins with a high ratio of pyrogallol-type B-rings, such as prorobietinidin and prodelphinidin. To clarify the factors affecting improvement of the formaldehyde-scavenging ability by ammonia treatment, the reaction behavior of condensed tannins during ammonia treatment was studied. Analyses using 13C-NMR and on-line methylation pyrolysis/gas chromatography/mass spectrometry revealed that on treatment of condensed tannins with ammonia, amino-substitution at C-4′ of the pyrogallol-type B-ring occurred to form a 4′-amino-3′,5′-dihydroxybenzene-type B-ring. It can be assumed that the introduction of a 4′-amino-3′,5′-dihydroxybenzene-type B-ring into the tannin molecule results in improved formaldehyde-scavenging ability.

Radical scavenging characteristics of condensed tannins from barks of various tree species compared with quebracho wood tannin

Holzforschung ◽  
2011 ◽  
Vol 65 (5) ◽  
Author(s):  
Rei Makino ◽  
Seiji Ohara ◽  
Koh Hashida
Keyword(s):  
Tree Species ◽  
Time Course ◽  
Condensed Tannin ◽  
Radical Scavenging ◽  
Reaction Times ◽  
Gas Chromatography Mass Spectrometry ◽  
Type B ◽  
Pyrolysis Gas ◽  
Nmr Spectrometry ◽  
In The Beginning

Abstract The object of this study was to elucidate the relationship between the chemical structure of purified condensed tannin polymers from tree species and their radical scavenging characteristics. By means of 13C-NMR spectrometry and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), four kinds of proanthocyanidins were identified: prorobinetinidins, profisetinidins, procyanidins, and prodelphinidins. The tannins were submitted to radical scavenging assays with DPPH and galvinoxyl radicals and from the time-course of the reactions was concluded: 1) Tannins with pyrogallol type B-ring scavenge radicals in the beginning faster than those with catechol type B-ring. 2) Tannins with catechol type B-ring needs more time to scavenge the same amount of radicals as those with pyrogallol type B-ring. 3) The IC50 values of tannins with catechol type B-ring decrease after longer reaction times with the galvinoxyl radical. 4) Radical scavenging with DPPH radical proceeds faster than that for the galvinoxyl radical.

Discriminative analysis of zooplankton individuals by pyrolysis–gas chromatography combined with on-line methylation

The Analyst ◽  
1996 ◽  
Vol 121 (6) ◽  
pp. 853-856 ◽  
Author(s):  
Yasuyuki Ishida ◽  
Shinichi Isomura ◽  
Shin Tsuge ◽  
Hajime Ohtani ◽  
Tatsuki Sekino ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Pyrolysis Gas ◽  
Pyrolysis Gas Chromatography ◽  
Line Methylation ◽  
On Line ◽  
Discriminative Analysis

Identification of Tackifying Resins and Reinforcing Resins in Cured Rubber

1999 ◽  
Vol 72 (1) ◽  
pp. 181-198 ◽  
Author(s):  
Seung Wook Kim ◽  
Gae Ho Lee ◽  
Gwi Suk Heo
Keyword(s):  
Mass Spectra ◽  
Structural Information ◽  
Direct Analysis ◽  
Gas Chromatography Mass Spectrometry ◽  
Pyrolysis Gas ◽  
On Line ◽  
Ft Ir ◽  
Characteristic Fragmentation ◽  
Fragmentation Patterns ◽  
Modified Wood

Abstract On-line thermogravimetic analysis/Fourier transform-infrared spectroscopy (TGA/FT-IR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) were employed to identify the tackifying resins and reinforcing resins in cured rubber. Py-GC/MS gave better results in the identification of the resins than the on- line TGA/FT-IR method. The mass spectra of resins in cured rubber were characterized by comparing the mass spectra of the pyrolyzates of raw resins and those of cured rubber containing the resins. t-Butylphenol acetylene condensed resin, coumarone-indene, C5-oligomeric Escorez 1102, modified wood rosin, and reinforcing modified cashew resin were studied. The results show that on-line Py-GC/MS is powerful tool in the analysis of the resins in cured rubber. The diagnostic m/z values of the resins for direct analysis in cured rubber were summarized. Reasonable structural information for resins could be acquired by the characteristic fragmentation patterns.

Biological and Morphological Studies on Low-Leukemia-Strain Mice with Hodgkin's-Like Neoplasia Induced by Serial Cell-Free Transmission of Leukemic Organs of SJL/J Strain Mice

1968 ◽  
Vol 26 ◽  
pp. 210-211
Author(s):  
S. Fujinaga ◽  
K. Maruyama ◽  
C.W. Williams ◽  
K. Sekhri ◽  
L. Dmochowski
Keyword(s):  
Tissue Culture ◽  
Type A ◽  
Reticulum Cell ◽  
Type B ◽  
Viral Origin ◽  
Serial Transfer ◽  
Strain Mouse ◽  
Morphological Studies ◽  
Cell Neoplasm ◽  
Free Material

Yumoto and Dmochowski (Cancer Res.27, 2098 (1967)) reported the presence of mature and immature type C leukemia virus particles in leukemic organs and tissues such as lymph nodes, spleen, thymus, liver, and kidneys of SJL/J strain mice with Hodgki's-like disease or reticulum cell neoplasm (type B). In an attempt to ascertain the possibility that this neoplasia may be of viral origin, experiments with induction and transmission of this neoplasm were carried out using cell-free extracts of leukemic organs from an SJL/J strain mouse with spontaneous disease.It has been possible to induce the disease in low-leukemia BALB/c and C3HZB strain mice and serially transfer the neoplasia by cell-free extracts of leukemic organs of these mice. Histological examination revealed the neoplasia to be of either reticulum cell-type A or type B. Serial transfer is now in its fifth passage. In addition leukemic spleen from another SJL/J strain mouse with spontaneous reticulum cell neoplasm (type A) was set up in tissue culture and is now in its 141st serial passage in vitro. Preliminary results indicate that cell-free material of 39th tissue culture passage can reproduce neoplasia in BALB/c mice.

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