TOXICITY TESTS OF A WATER-SOLUBLE PHENOLIC FRACTION (THUJAPLICIN-FREE) OF WESTERN RED CEDAR

1954 ◽  
Vol 32 (1) ◽  
pp. 308-309 ◽  
Author(s):  
J. W. Roff ◽  
J. M. Atkinson
1969 ◽  
Vol 47 (23) ◽  
pp. 4495-4498 ◽  
Author(s):  
Harold MacLean ◽  
B. F. MacDonald

The last of nine lignans detectable by thin-layer chromatography in the hot-water soluble extractives of western red cedar (Thujaplicata Donn) heartwood has been determined as 6-hydroxy-2(hydroxy-methyl)-7-methoxy-4-(3′,4′-dihydroxy-5′-methoxyphenyl)-3-naphthoic acid lactone (plicatinaphthalene 2) by spectrometric methods, by degradation studies of derivatives, and by preparation of its trimethyl ether derivative 3 from dehydroanhydropicropodophyllin by opening of the methylenedioxy group with boron trichloride.


1976 ◽  
Vol 33 (12) ◽  
pp. 2703-2709 ◽  
Author(s):  
G. B. Peters ◽  
H. J. Dawson ◽  
B. F. Hrutfiord ◽  
R. R. Whitney

Water-soluble extractives from western red cedar heartwood, bark, and foliage were investigated for their toxicity to aquatic organisms. The heartwood lignans and bark extractives were found to be moderately toxic, but the foliage terpenes and heartwood tropolones were more toxic, causing 50% mortality to coho salmon (Oncorhynchus kisutch) fry at 0.33 and 2.7 mg/liter, respectively. Tropolones were significantly less toxic to invertebrates than to free-swimming stages of the fish tested. Fry were found to be the stage of development of coho salmon (O. kisutch) most sensitive to the tropolones, and eyed eggs the least sensitive. Sensitivity of the coho fry to tropolones was moderated by previous sublethal exposure or the presence of a chelatable cation. Results from field studies and a leaching study indicate that directly releasing cedar leachate from landfills or allowing logging debris to enter streams should be avoided.


1993 ◽  
Vol 23 (6) ◽  
pp. 1052-1059 ◽  
Author(s):  
Rodney J. Keenan ◽  
Cindy E. Prescott ◽  
J.P. Hamish Kimmins

Biomass and C, N, P, and K contents of woody debris and the forest floor were surveyed in adjacent stands of old-growth western red cedar (Thujaplicata Donn)–western hemlock (Tsugaheterophylla (Raf.) Sarg.) (CH type), and 85-year-old, windstorm-derived, second-growth western hemlock–amabilis fir (Abiesamabilis (Dougl.) Forbes) (HA type) at three sites on northern Vancouver Island. Carbon concentrations were relatively constant across all detrital categories (mean = 556.8 mg/g); concentrations of N and P generally increased, and K generally decreased, with increasing degree of decomposition. The mean mass of woody debris was 363 Mg/ha in the CH and 226 Mg/ha in the HA type. The mean forest floor mass was 280 Mg/ha in the CH and 211 Mg/ha in the HA stands. Approximately 60% of the forest floor mass in each forest type was decaying wood. Dead woody material above and within the forest floor represented a significant store of biomass and nutrients in both forest types, containing 82% of the aboveground detrital biomass, 51–59% of the N, and 58–61% of the detrital P. Forest floors in the CH and HA types contained similar total quantities of N, suggesting that the lower N availability in CH forests is not caused by greater immobilization in detritus. The large accumulation of forest floor and woody debris in this region is attributed to slow decomposition in the cool, wet climate, high rates of detrital input following windstorms, and the large size and decay resistance of western red cedar boles.


New Forests ◽  
1994 ◽  
Vol 8 (3) ◽  
pp. 231-247 ◽  
Author(s):  
Raymund S. Folk ◽  
Steven C. Grossnickle ◽  
John E. Major ◽  
James T. Arnott

2017 ◽  
Vol 11 (1) ◽  
pp. 79-81
Author(s):  
Kole F. Adelalu ◽  
Xiao-Jian Qu ◽  
Yan-Xia Sun ◽  
Tao Deng ◽  
Hang Sun ◽  
...  

IAWA Journal ◽  
2002 ◽  
Vol 23 (2) ◽  
pp. 201-211 ◽  
Author(s):  
Simon Ellis ◽  
Paul Steiner

Five wood species, Oregon ash (Fraxinus latifolia Benth.), Balau (Shorea spp.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), Western red cedar (Thuja plicata Donn ex D. Don), and Trembling aspen (Populus tremuloides Michx.) were loaded in compression longitudinally, radially and tangentially. The wood cubes were conditioned to one of four moisture contents prior to loading. Small cubes were loaded until no void space remained after which samples were released and soaked in water. Stress /strain curves were recorded over the whole range of strain and cube thicknesses were recorded at the end of the compression, after release from the testing apparatus, and after soaking in water. Denser woods resulted in a greater Young’s modulus, higher levels of stress and shorter time to densification than did less dense woods. Higher initial moisture contents apparently increased the plasticity of the wood leading to a lower Young’s modulus and lower levels of stress during compression, greater springback after release of stress and greater recovery after swelling in water. Differences observed in the radial and tangential behaviours were believed to be due to the supporting action of the rays when the wood was compressed in the radial direction in balau and trembling aspen and to the relative difference between the lower density earlywood and higher density latewood regions in ash, Douglas-fir and western red cedar.


Holzforschung ◽  
2002 ◽  
Vol 56 (2) ◽  
pp. 185-190 ◽  
Author(s):  
Anastasios Koumoutsakos ◽  
Stavros Avramidis

2020 ◽  
Author(s):  
Subhodeep Bhattacharya ◽  
Gokul Rajan ◽  
Kiranam Chatti ◽  
Joby Joseph

Immersion of a ubiquitously used brand of translucent pressure sensitive adhesive tape (TLPSAT), in normal water was found to confer anaesthetic-like effects to the resultant solution (TLPSAT A). We characterised this anaesthetic-like property by assessing its dose-dependence, behavioural effects and toxicity in zebrafish (Danio rerio) in comparison to other commonly used anaesthetics, namely 2-phenoxyethanol (2-PE) and tricaine methanesulfonate (TMS). Toxicity tests showed that it is comparable to TMS and safer than 2-PE in terms of mortality. We also observed differences in the nature of opercular movement due to the three compounds with differences in the power spectrum. Electrophysiological investigations using grasshopper (Hieroglyphus banian) as a model system led us to conclude that nicotinic acetylcholine (nACh), γ-aminobutyric acid (GABAergic) mechanisms, or voltage gated calcium (Ca2+), sodium (Na+) and potassium (K+) channels in insects are not affected by this anaesthetic at the concentrations effective in fish. Electroretinography (ERG) measurement from honeybees (Apis mellifera) in the presence of the different compounds yielded abolishment of the receptor potential under TMS or 2-PE perfusion whereas all ERG components were preserved under TLPSAT A perfusion, indicating that the Ca2+ dependent channels and photo-transduction machinery in bees are not potentially affected by TLPSAT A. Thus, the unknown compound(s) in the TLPSAT aqueous extract likely induce(s) anaesthesia in zebrafish via a mechanism unlike that of TMS and 2-PE.


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