Investigation of Carbohydrate Compositions for Poplar I-214 and Chinese Fir

Carbohydrates are main compositions for wood (Menachem et al. 1991). The chemical components of poplar I-214 and Chinese fir have been reported (Huang Luohua et al. 2002; Qin Tefu et al. 2003). Through the studies of carbohydrate compositions of poplar I-214 and Chinese fir, different composition of monosaccharides can be found in both poplar I-214 and Chinese fir. 1 MATERIALS AND METHODS 1.1 Materials Wood samples of Chinese fir (Cunninghamia lancedata) and poplar I-214 (Populus…     

Metabolism of the herbicides chlorotoluron, diuron, linuron, simazine, and atrazine by CYP1A9 and CYP1C1 from Japanese eel (Anguilla japonica)

Through the use of a number of bioconversion experiments we demonstrated that P450 proteins (CYP1A9 and CYP1C1) from Japanese eel (Anguilla japonica) metabolized a number of herbicides and the drug phenacetin. We performed bioconversion experiments in which substrates were added directly to incubation medium. The resulting metabolites were extracted and analyzed by high-performance liquid chromatography. Proteins CYP1A9 and CYP1C1 metabolized 50 nmol of the drug phenacetin to yield 12.1 and 1.1 nmol of product (acetaminophen), respectively. Further incubation of CYP1A9 with 50 nmol of the herbicides chlorotoluron, diuron, linuron, simazine, or atrazine yielded 16.5, 18.5, 7.3, 1.6, or 0.8 nmol of product, respectively. CYP1C1 also metabolized linuron, diuron, and simazine yield 5.4, 4.6, or 0.7 nmol of product, respectively. Next, polyclonal antibody was isolated by immunizing with two conjugated-peptides (amino acid residues 272–290 and 294–310) of CYP1A9. This antibody did not recognize human CYP1A2 or CYP1C1. Western blotting using the antibody revealed one band in the livers of Japanese eel and tilapia (Oreochromis niloticus). Theses results suggest that CYP1A9 and CYP1C1 metabolize herbicides, and that CYP1A9 is an useful biomarker of contamination when detected with this antibody.     

Characterization of sp<Superscript>2</Superscript>- and sp<Superscript>3</Superscript>-bonded carbon in wood charcoal

Japanese cedar (Cryptomeria japonica) preheated at 700°C was subsequently heated to 1800°C and characterized by electron microscopy, X-ray diffraction, and micro-Raman spectroscopy. The degree of disorder of carbon crystallites and the amount of amorphous phase decreased considerably with an increase in heat treatment temperature to 1400°C, while carbon crystallites clearly developed above this temperature, showing that the microstructure of carbonized wood undergoes drastic changes around 1400°C. Besides showing the bands for sp²-bonded carbon, the Raman spectra showed a shoulder near 1100 cm⁻¹ assigned to sp³-bonded carbon. With an increase of heat treatment temperature, the peak position of the Raman sp³ band shifted to a lower frequency from 1190 to 1120 cm⁻¹, which is due to the transformation of sp³-bonded carbon from an amorphous phase to a nanocrystalline phase. These data showed that the microstructure of carbonized wood from 700° to 1800°C consisted of the combination of sp²- and sp³-bonded carbon, which is probably due to the disordered microstructure of carbonized wood. It is suggested that the sp³-bonded carbon is transformed from an amorphous structure to a nanocrystalline structure with the growth of polyaromatic stacks at temperatures above 1400°C.     

Characterization of moderate resistance to QoI fungicides in Pestalotiopsis longiseta and polymorphism in exon–intron structure of cytochrome b gene

Qo inhibitor (QoI) fungicides are used to control gray blight caused by Pestalotiopsis longiseta in Japanese tea cultivation. However, field isolates of P. longiseta highly resistant to QoI fungicides were found in 2008, resulting in failure of QoI fungicidal control. This resistance was attributed to a mutation in the cytochrome b gene (cytb) in which alanine was substituted for glycine at position 143 (G143A). In 2009–2010, we detected field isolates that had an intermediate reaction between sensitive and resistant isolates in a preliminary assay. These isolates showed intermediate sensitivity to azoxystrobin and kresoxim-methyl on PDA plates. The intermediate reaction to azoxystrobin was also confirmed on detached tea leaves. Consequently, they were considered moderately resistant to QoI fungicides. Nucleotide sequencing of cytb showed that moderate resistance correlated with a single point mutation; leucine was substituted for phenylalanine at amino acid position 129 (F129L). Sequence analysis also revealed two types of cytb, with or without an intron between codons 131 and 132, in P. longiseta. F129L and G143A mutations were detected in both types of cytb according to their QoI resistance. This result suggests that G143A and F129L mutations have each occurred at least twice in the P. longiseta population.     

Infectivity of a Japanese isolate of <Emphasis Type="Italic">Oidium neolycopersici</Emphasis> KTP-01 to a European tomato cultivar resistant to <Emphasis Type="Italic">O. lycopersici</Emphasis>

The infectivity of a Japanese isolate of tomato powdery mildew, Oidium neolycopersici KTP-01, to tomato cultivars was examined using a resistant cultivar Grace bred in The Netherlands to O. lycopersici, which was recently proposed to be renamed O. neolycopersici. Grace was severely infected with KTP-01, and its susceptibility was similar to that on susceptible tomato cultivars Moneymaker and Ponderosa, suggesting that KTP-01 differs in pathogenicity on tomatoes from those of European and American isolates.     

Sulfuric acid bleaching of kraft pulp 1: Bleaching of hardwood and softwood kraft pulps

To develop a new nonchlorine bleaching technology, hardwood and softwood kraft pulps, before and after oxygen-alkali predelignification, were treated with dilute sulfuric acid solutions (pH 1.0-1.8) at 100°C for 1 h and then extracted with aqueous sodium hydroxide at 70°C for l h. Hardwood kraft pulp was successfully bleached. The delignification selectivity was similar to that seen with oxygen-alkali bleaching; and it was greatly enhanced by the addition of sodium nitrate and sodium nitrite. The sulfuric acid bleaching can replace the presently adopted oxygen and chlorine stages if the additives are allowed. This bleaching process was also effective for oxygen-bleached hardwood kraft pulp, but it was less effective for softwood kraft pulp and oxygen-bleached softwood kraft pulp. The effectiveness of the addition of sodium nitrate and sodium nitrite was more apparent for softwood kraft pulp than for hardwood kraft pulp.Part of this report was presented at the 7th International Symposium on Wood and Pulping Chemistry, Beijing, July 1993