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1.
The content of the glyceraldehyde-2-aryl ether-type structure in water-soluble lignin–carbohydrate complex (LCC) fractions, which were obtained from Japanese cedar and birch residual wood meal after milled wood lignin isolation, was determined by ozonation. Quite high amounts of the glyceraldehyde-2-aryl ether-type structure were found in water-soluble LCC fractions of both species; about 3–5 times higher than those of other fractions. This result, as well as the high content of the β-1 structure in these fractions shown in our previous reports, suggest that lignin in these fractions has the characteristics of endwise-type lignin, because the glyceraldehyde-2-aryl ether-type structure and β-1 structure are typical characteristics of this type of lignin fraction. These results are in good agreement with the generally accepted hypothesis that the glyceraldehyde-2-aryl ether-type structure and β-1 structure are generated at the same time by a radical coupling reaction. The results also indicated that these two structures are present in close proximity in the lignin.  相似文献   
2.
The formation of a complex with aluminum by low molecular weight compounds and saponified ozone-treated kraft lignins was evaluated based on the decrease in pH of their solutions on the addition of 0.1 M AlCl3. Decreases in pH were observed with the solutions containing compounds having adjacent carboxyl groups (oxalic acid), carboxyl/alcoholic hydroxyl groups (glycolic acid), carboxyl/formyl groups (glyoxylic acid), and phenolic hydroxyl groups (protocatechuic acid) on the addition of 0.1 M AlCl3. The malonic and phthalic acids, having two carboxyl groups, were also effective. These results show that the compounds were effective in forming complexes with aluminum. This finding corresponds to the fact that aluminum toxicity is reduced by formation of a complex with aluminum, except in phthalic acid. The chemical structures stated above in ozone-treated kraft lignins contribute, at least partly, to the complex with aluminum. The pH of solutions containing saponified ozone-treated kraft lignins and alkaline-treated kraft lignin decreased more than that without modified kraft lignins on the addition of 0.1 M AlCl3, showing that they were effective in forming a complex with aluminum. The high molecular weight part of saponified ozone-treated kraft lignin was effective in forming a complex with aluminum and in reducing its toxicity.  相似文献   
3.
New Forests - The forestry sector has been able to sustainably satisfy the increasing global demand for forest products, thereby positively impacting the economy, while mitigating climate change....  相似文献   
4.
The cladistic analysis of the V4 domain sequences, performed by UPGMA, the neighbor-joining, and parsimony methods, revealed that the 19 Pleurotus strains tested in this study evolved along three lineages, each corresponding to a separate biological species: the Pleurotus ostreatus complex, the Pleurotus pulmonarius complex, and Pleurotus eryngii. Moreover, the cladistic positions of the 3 biological species show that the P. ostreatus complex and P. eryngii were derived from a common ancestor at a later stage of evolution, and that the common ancestor had diverged from the lineage of the P. pulmonarius complex during an earlier evolutionary event. The sequences of the 5 portion of the mt SSU rDNA among the strains of the P. ostreatus complex had 99.2%–99.6% homology. All test strains in the P. pulmonarius complex had completely identical sequences. The homology of the strain sequences between the P. ostreatus complex and the P. pulmonarius complex ranged from 96.0% to 96.3%. The sequence of the strain of P. eryngii showed 97.8%–98.3% and 96.5% homologies with those of the strains in the P. ostreatus and the P. pulmonarius complexes, respectively.  相似文献   
5.
This study examined the feasibility of near infrared spectroscopy as a novel technique for log assessment on the basis of wood property. Near infrared (NIR) spectra were obtained from the transverse section of green log and multivariate regression analysis was carried out to predict the stiffness of veneer processed from the log. The stiffness of the veneer was dynamic modulus of elasticity measured using ultrasonic method. The calibrations of veneer stiffness had moderate relationships between measured and NIR-predicted values, with regression coefficients ranging from 0.84 to 0.88. The calibration equations were applied to the test set and it was found that predictions were also well fitted, with regression coefficients ranging from 0.67 to 0.89. The results indicate that the variation of wood stiffness within the logs could be assessed using the NIR spectra from the cross-section of logs. The spectra were obtained from green condition of the log and the stiffness of veneer was measured after kiln drying. Thus, the results imply that the wood stiffness in dry condition could be predicted using the spectra collected from green logs. If the models obtained in this study put into the imaging system, the two-dimensional map of the stiffness would be visualized on the cross-section of logs. The NIR spectroscopy coupled with imaging system could compensate the weak point of the traditional methods for log assessment.  相似文献   
6.
The exploitation of agro-industrial wastes is a strategy to add value to seedling production and reduce environmental problems.The production chain for processed peaches generates,approximately,21,000 tons of fruit worldwide,and the pits are used mainly to generate energy.The objective of the study was to investigate the use of different proportions of ground peach pits(GPP)as a substrate component for seedling growth of Eucalyptus dunnii in the nursery and field.Different proportions of GPP mixed with either commercial substrate(CS)or with brown peat(BP)were tested.The physical and chemical properties of the substrates,the morphological and physiological attributes of the seedlings and their correlation with substrate properties were evaluated.The GPP increased the density,aeration space and pH and reduced total porosity,liquid retention and electric conductivity of the substrate.The use of this component resulted in hormesis,a biphasic dose–response model in which low levels of exposure to this component stimulated biological performance of plants and high levels of exposure inhibited performance.For improved seedling growth in the nursery and adequate post-planting development of E.dunnii,GPP with CS is recommended at 20%of the total substrate and with BP between 15 and 30%.  相似文献   
7.
Real-time polymerase chain reaction (PCR) analysis of the 3′-portion of the mitochondrial 16S RNA gene (rDNA) coding sequence was used to determine flying fish paste in ago-noyaki. We quantified the amount of flying fish paste in ago-noyaki samples using flying fish-specific primers (Tobi16SF3/Tobi16SR) and universal primers (Univ16SF2/Univ16SR2). Using real-time PCR of standard ago-noyaki, a standard equation was obtained (y = 1.08x − 3.20; R 2 = 0.977). This equation was then used to estimate the relative flying fish paste contents of eight commercially available ago-noyaki and two similar products. These results verified that the ago-noyaki products that had already been labeled with the E-mark deserved this status.  相似文献   
8.
Nucleotide sequence and polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the 3′-portion of the mitochondrial 16S RNA gene (rDNA) coding sequence were used to differentiate between flying fishes and other fishes that are frequently used in ago-noyaki production. In this study, we successfully distinguished between flying fishes and the other fishes by combining amplified DNA fragments with universally designed primers and digesting the PCR products with AfaI and MfeI restriction endonucleases. PCR-RFLP of 15 ago-noyaki, 2 noyaki, and 8 other processed flying-fish products were analyzed to authenticate flying-fish content among processed seafood products. After digestion of the PCR products with both enzymes, we found that all ago-noyaki and processed flying fish products contained either two or three DNA fragments of ~200, 300, and 530 bp, and noyaki samples (which do not contain flying fish) contained only one fragment of ~530 bp. Here, we present a new procedure to confirm the content of flying-fish meal in ago-noyaki.  相似文献   
9.
Lignin prepared by a modified Klason method (KSL) was modified with ozone followed by alkaline treatments. The original and modified KSLs were subjected to a plant growth test with radish (Raphanus sativus L. var. radicula Pers.) in the presence of AlCl3 (37.5 μM) to assess their ability to reduce aluminum toxicity. The formation of an aluminum complex with these KSLs was also examined by potentiometry. Neither the original nor alkaline-treated KSLs had an effect on aluminum toxicity or the formation of a complex, except for the alkaline-treated KSL at a maximal dose of 250 mg/l, which reduced aluminum toxicity. However, all the KSLs modified with ozone and alkali were effective at forming a complex and reducing aluminum toxicity. The dose of saponified ozone-treated KSLs required to reduce aluminum toxicity became lower and their water solubility increased as the ozone treatment was prolonged. These findings clearly show that water solubility and the ability to form a complex with and reduce the toxicity of aluminum were improved by ozone treatment of KSL.  相似文献   
10.
The aim of the study was to investigate the location of motor neuron somata of geniohyoid muscle in rat. Nine Sprague‐Dawley rats were used in this study. Operations were performed under general anaesthesia. Nembutal sodium, 40 mg per kg intraperitoneally was used for anaesthesia. 0.02 to 0.05 ml of 30% horseradish peroxidase (Sigma Type VI) solution in normal saline was injected into the exposed right geniohyoid muscle. After 48 hr, the animals were fixed by perfusion through left ventricle of heart, first by 100 ml normal saline and then with 500 ml of 1.25% glutaraldehyde and 1% paraformaldehyde in 0.1 M phosphate buffer, pH 7.4, at room temperature, and finally with 500 ml of 10% sucrose in the same buffer at 4°C. The medulla oblongata and first cervical segment of spinal cord were removed, kept in 10% sucrose in above phosphate buffer at 4°C for 24 hr. Thereafter, their serial transverse sections were cut in a cryostat at a thickness of 60 μm. The sections were treated according to tetramethyl benzidine (TMB)‐horseradish peroxidase (HRP) method. HRP‐labelled neuron somata were observed at the following sites: (a) In ventral part of right main hypoglossal nucleus in upper two‐thirds of the closed part of medulla oblongata. (b) In ventrolateral subnucleus of hypoglossal nucleus in lower third of closed part of medulla oblongata. (c) At spinomedullary junction, they were located in dorsomedial part of right ventral grey column; a few were also seen here scattered on right side of central canal and among corticospinal fibres.  相似文献   
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