Storage-induced emissions from different wood species

In this study, the extractive contents and the storage-induced emissions from chips of Salix alba, Betula pendula, Populus tremula, and Alnus glutinosa are compared with emissions from Pinus sylvestris chips. Soxhlet extraction was performed, and carbon monoxide (CO) and O2 concentration in the gas phase as well as gas chromatography-mass spectrometry analysis of volatile organic compounds were analyzed. Pinus sylvestris showed the highest extractive content in the petrol ether fraction and emitted CO in the highest concentration. Salix alba, B. pendula, P. tremula, and A. glutinosa have lower extractive contents in the petrol ether fraction and the CO concentrations decreased in the headspace accordingly. The emission of aldehydes was lower in the case of woods with lower petrol ether contents (P. sylvestris, S. alba, and B. pendula), but the situation was not as clear for P. tremula and A. glutinosa. The origin of CO and aldehyde emissions is discussed in view of the possible oxidative degradation processes of lipids and terpenes.

Biological and chemical characteristics of "included sapwood" of Juniperus virginiana L.

The reddish-violet heartwood of Juniperus virginiana L. contains irregularly distributed and longitudinally oriented streaks of light-coloured wood, described as “included sapwood”. A histological study revealed that a blockage of the rays, which is caused by wounds often associated with tiny shakes, branch stubs and included bark, may lead to this anomaly. A study of fresh wood immediately after felling of the trees showed that “included sapwood” lacks physiological activity similar to the adjacent normal heartwood. Cellular UV-spectroscopic analysis revealed a secondary metabolism particularly of phenolic compounds in the pit membranes of tracheids during “included sapwood” formation, whereas the reddish-violet flavonoid compounds do not develop in this anomalous wood. Chemical analyses of petrol ether, diethyl ether, acetone and ethanol/water extracts of sapwood, “included sapwood” and heartwood showed that the accessory compounds cedrol, α-cedrene, widdrol, thujopsene and cuparene increased in “included sapwood” compared to sapwood. As opposed to the reddish-violet heartwood compounds, these sesquiterpenes turned out to be highly toxic against a brown-rot fungus in a bioassay. These findings justify defining “included sapwood” as a heartwood anomaly, since the important wood characteristics of this tissue obey the definition of heartwood rather than sapwood. This anomaly should no longer be a reason to exclude this type of wood from commercial utilisation.

Studies on Tissue Thromboplastin II. Species Specificity*)

Summary1. Purified brain tissue thromboplastins of human, bovine and chicken origin have been tested on homologous and heterologous plasmas.2. Purified brain tissue thromboplastin is species specific.3. Lipid extracts from purified brain tissue thromboplastin prepared with pyridin show a negligable residual species specificity, probably caused by a slight contamination with brain tissue thromboplastin.4. The activity curves of our lipid extracts differ from typical curves expected for lipid activators by a less distinct inhibition in high concentrations probably caused by a different composition of petrol-ether and pyridin extracts.5. The protein part of tissue thromboplastin does not activate prothrombin in any system.6. The protein part of tissue thromboplastin of one species could be combined with the lipid part of another species to form an active tissue thromboplastin.7. The species specificity of these combinations was determined by the source of protein used.

Graded levels of herringmeal to bacon pigs, effect on growth rate, feed efficiency and bacon quality

1. The relationship between the level of feeding herringmeal and its effect on growth rate, feed efficiency and bacon quality has been examined in nine experiments, each consisting of three groups of seven (in one series six pigs). All experiments concerned herringmeal with about 7% petrol ether extracted fat, fed in combination with ground cereal grains and concentrates (Table 2).2. Seven levels of feeding were tried. In the live weight period 20–30 kg they amounted to 3, 4, 5, 6, 8, 10 and 12%, herringmeal respectively. Later the percentages were successively reduced as follows: in the period 30–50 kg live weight 3/4, in the period 50–65 kg 1/2 and in the period 65–80 1/4 of the original amounts. No herringmeal was fed from 80 to 90 kg when the pigs were slaughtered (Table 1).3. Increased levels of herringmeal produced increased growth rate and also brought about an increased feed efficiency. Most of the response was obtained with moderate levels, i.e. additions starting with 6–8%. Higher levels exerted more total effect, but these further accelerations progressively lessened. For initial additions of 6% herringmeal the growth rate improved on an average estimated at 8% and the feed efficiency by 5% compared with the performances of the pigs on an all-vegetable control diet, whereas corresponding figures for initial additions of 12% were about 13 and 7, respectively. Lower levels proved of little benefit (Tables 3 and 4 and Figs. 1 and 2). Growth-promoting effect of levels of 6% or more proved significant.