Wood Of Coniferous Trees Research Articles

Two conifer GUX clades are responsible for distinct glucuronic acid patterns on xylan.

Wood of coniferous trees (softwood), is a globally significant carbon sink and an important source of biomass. Despite that, little is known about the genetic basis of softwood cell wall biosynthesis. Branching of xylan, one of the main hemicelluloses in softwood secondary cell walls, with glucuronic acid (GlcA) is critical for biomass recalcitrance. Here, we investigate the decoration patterns of xylan by conifer GlucUronic acid substitution of Xylan (GUX) enzymes. Through molecular phylogenetics we identify two distinct conifer GUX clades. Using transcriptional profiling we show that the genes are preferentially expressed in secondary cell wall forming tissues. With invitro and in planta assays we demonstrate that conifer GUX enzymes from both clades are active glucuronyltransferases. Conifer GUX enzymes from each clade have different specific activities. While members of clade one add evenly spaced GlcA branches, the members of clade two are also capable of glucuronidating two consecutive xyloses. Importantly, these types of xylan patterning are present in softwood. As xylan patterning might modulate xylan-cellulose and xylan-lignin interactions, our results further the understanding of softwood cell wall biosynthesis and provide breeding or genetic engineering targets that can be used to modify softwood properties.

Galactoglucomannan-rich hemicellulose extract from Norway spruce (Picea abies) exerts beneficial effects on chronic prostatic inflammation and lower urinary tract symptoms in vivo

Galactoglucomannan (GGM) is the main hemicellulose class in wood of coniferous trees and could be potentially utilized as a possible health-promoting substance for food and pharmaceutical industry. Our aim was to evaluate effects of orally administered GGM-rich extract from Norway spruce in a rat model of chronic prostatitis associated with lower urinary tract symptoms (LUTS). Prostatic inflammation and LUTS was induced in male rats using testosterone and 17β-estradiol exposure for 18 weeks. Rats were treated with 2% GGM dissolved in drinking water during weeks 13–18. Pelvic pain response, LUT function and histopathological evaluation of the prostate were assessed. The results show that hormonal exposure induced LUTS seen as decreased urine flow rate, increased bladder pressure, voiding times, bladder capacity and residual urine volumes. GGM had positive effects on urodynamical parameters by decreasing the basal bladder pressure, increasing the urine flow rate and volume, reducing the residual volume and increasing micturition intervals. GGM reduced the extent of the hormone exposure-induced prostatic inflammation. Increase of pelvic pain induced by hormone exposure was only slightly affected by GGM treatment. The results suggest that orally administered GGM may have potential usage for improving lower urinary tract function associated with chronic prostatic inflammation.

NEW SPECIES OF THE GENUS CERATOCYSTIS

A study of the species of Ceratocystis found in Ontario on decaying slash has been made and most of the species grown in pure culture. The characteristics of the genus and the separation of species are discussed. Four species found on wood of coniferous trees are described as new. Illustrations are included for all of these. Ceratocystis brunneocrinita Wright and Cain is described from several collections of Abies balsamea. The perithecia have brown ostiolar hyphae and the ascospores appear rectangular. Ceratocystis europhioides Wright and Cain, on Pinus and Picea, has ascospores similar to but larger than the nonostiolate Europhium trinacriforme Parker. Ceratocystis falcata Wright and Cain, on Pinus, resembles Ceratocystis minuta (Siem.) Hunt but is distinguished by the longer, septate ascospores. Ceratocystis sagmatospora Wright and Cain, on Pinus and Picea, has saddle-shaped ascospores with elaborate gelatinous sheaths.

The Staff-Tree, Celastrus scandens, as a Former Food Supply of Starving Indians

IN many kinds of hard and horny seeds there is present, as a reserve material, a carbohydrate which upon hydrolysis yields mannose (a simple sugar closely related to glucose). This carbohydrate has been named mannan. It is one of the hemi-celluloses, a group of substances closely resembling in appearance the true celluloses, but easily resolved into simpler carbohydrates by the hydrolytic action of enzymes or of dilute acids. There is no lack of evidence that mannan which occurs abundantly in the so-called vegetable ivory, Phytelephas macrocarpa, and in the seeds of many other palms, as well as in the wood of coniferous trees, is in spite of its hardness, fit food for camels, neat cattle, sheep, and various rodents. This is illustrated in the girdling of pine trees by mice, as recorded by Thoreau in Walden. ' He says:There were scores of pitch-pines around my house, from one to four inches in diameter, which had been gnawed by mice the previous winter,a Norwegian winter for them, for the snow lay long and deep, and they were obliged to mix a large proportion of pine bark with their other diet. These trees were alive and apparently flourishing at mid-summer, and many of them had grown a foot, though completely girdled; but after another winter such were without exception dead. It is remarkable that a single mouse should thus be allowed a whole pine tree for its dinner, gnawing round instead of up and down it; but perhaps it is necessary in order to thin these trees, which are wont to grow up densely. It is known that the root of a Japanese plant, Conophallus konnjaku, rich in mannan is used as human food, and the question may fairly be asked whether the former use of bark bread by the inhabitants of Scandinavia might not have been dependent upon the mannan in the bark. After discussing this matter in the

The Diameter-Increment of the Wood of Coniferous Trees at Braemar in Relation to climatic Conditions

The Diameter-Increment of the Wood of Coniferous Trees at Braemar in Relation to climatic Conditions