In vitro reduction of manganese dioxide by a ferrireductase system from the white-rot fungus <Emphasis Type="Italic">Phanerochaete sordida</Emphasis> YK-624

Reduction of manganese dioxide is demonstrated for an in vitro ferrireductase system that includes NADPH-dependent ferrireductase and the iron-binding compound (IBC) isolated from the white-rot fungus Phanerochaete sordida YK-624. The Fe(II)–IBC complex was more effective in reducing manganese dioxide to Mn(II) than were complexes of Fe(II) and organic acids of low molecular weight such as nitrilotriacetate, although IBC also reduced manganese dioxide to Mn(II) in the absence of Fe(II). The generated Fe(III)–IBC complex was a better substrate for NADPH-dependent ferrireductase than were other ferric chelates, suggesting that the Fe(III)–IBC complex is reduced to an Fe(II) complex by NADPH-dependent ferrireductase. Moreover, production of the Fe(III)–IBC complex by the reduction of manganese dioxide in a reaction system containing Fe(II) and IBC was observed to be coupled to reduction of the Fe(III)–IBC complex by NADPH-dependent ferrireductase. These results indicate that the ferrireductase system of P. sordida YK-624 plays an important role in the reduction of manganese dioxide, which is necessary for the production and function of manganese peroxidase.     

Change in oxidation state of manganese atoms in kraft pulp during biological bleaching with white-rot fungusPhanerochaete sordida YK-624

Change in the oxidation state of manganese atoms in unbleached hardwood kraft pulp (UKP) during the biological bleaching of UKP withPhanerochaete sordida YK-624 was determined by the electron spin resonance (ESR) method. The spectrum of Mn(II), which reveals hyperfine splitting, was not observed in the ESR analysis of UKP, but the spectrum for manganese dioxide was observed. After fungal treatment of UKP withP. sordida YK-624, the spectrum of Mn(II) was detected. The reduction of manganese dioxide was triggered by the increase in NADPH-dependent ferrireductase activity. It is concluded that the manganese dioxide dominant in UKP was reduced byP. sordida YK-624 to Mn(II), which stimulates the production and function of manganese peroxidase.     

NADPH-dependent ferrireductase produced by white-rot fungusPhanerochaete sordida YK-624

An intracellular, soluble ferrireductase thought to be involved in the reduction of manganese dioxide by white-rot fungusPhanerochaete sordida YK-624 was purified for the first time. Two isoenzymes, NAD(P)H-dependent and NADPH-dependent, respectively, were detected by hydrophobic chromatography. The NADPH-dependent ferrireductase was purified to homogeneity by ammonium sulfate fractionation, hydrophobic interaction, gel permeation, and anion-exchange chromatography. The purified protein, which is monomeric, has a molecular mass of 35 kDa (determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) and pl 5.1 (determined by isoelectric focusing). The purified protein did not use cellobiose as an electron donor. The purified protein reduced Fe(III)-nitrilotriacetate complex, Mn(III)-malonate complex, methoxy-p-benzoquinone, and cytochrome c; veratraldehyde, 2-hydroxy-1,4-naphthoquinone, phenazine methosulfate, and plumbagin could not be reduced. Particularly, the protein showed the highest reducing rate for Fe(III)-organic acid complexes, such as Fe(III)-nitrilotriacetate, among these electron acceptors.     

A new norlignan from Taxodium ascendens

A new norlignan, (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (1), together with 9 known compounds were isolated from the branches and leaves of Taxodium ascendens. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidences. Methanol extract showed inhibitory activity on carbonic anhydrase II with an IC₅₀ value of 4.27 µg/ml, acetone extract and methanol extract inhibited activity of cathepsin B with IC₅₀ values of 2.12 and 3.71 µg/ml, respectively.     

Manufacture of wood-cement boards VII: cement-hardening inhibitory compounds of hannoki (Japanese alder,Alnus japonica Steud.)

To identify the cement-hardening inhibitory components of hannoki (Japanese alder,Alnus japonica Steud.), methanol extractives were fractionated by successive organic solvent extraction and column chromatography. Chromatographie analysis and inhibitory indices of the solvent-soluble fractions suggested that glucose and sucrose seem to be the main cement-hardening inhibitory components of Japanese alder. As these compounds are metabolized in vivo even after cutting, the particles after withering are desirable as raw material for wood-cement board.     

Volatile composition analysis by solid-phase microextraction applied to oak wood used in cooperage (Quercus pyrenaica and Quercus petraea): effect of botanical species and toasting process

The purpose of this study was to investigate the sorption of selected volatile substances from oak wood-chip samples (Quercus pyrenaica Willd. and Quercus petraea L.) subjected to different toasting levels, namely, without toasting, with medium toasting, and with strong toasting, through the use of solid-phase microextraction (SPME). The main volatile compounds identified as a function of the toasting level and botanical species were furfural, hexanal, α-pinene, d-limonene, decanal, vitispirane, ethyl hexanoate, cis-3-methyl-γ-octalactone (“oak lactone” or “whisky lactone”), α-terpineol, p-xylene, and nonanal. Considering the data obtained from the toasted woods (medium and strong intensity) in comparison with those of nontoasted woods, it can be pointed out that the average peak area and the number of compounds identified in the gas chromatogram decreased during the toasting process. In general, regarding the compounds analyzed, quantitative differences were found between the two oak wood species under study. High values of volatile compounds were found in Quercus pyrenaica oak wood chips. In addition, for the number of compounds identified in oak wood extracts and directly extracted from solid oak wood chips by SPME, it is concluded that the best extraction process for volatile compounds from oak wood is the use of oak wood-chip liquid extracts.     

Formylated phloroglucinols from Eucalyptus loxophleba foliage

Two new naturally occurring formylated phloroglucinol compounds (FPCs), a dimer, loxophlebal B (10) and a cyclized FPC, loxophlebene (8) together with eight other formylated phloroglucinols (1–7 and 9) were isolated from the chloroform-methanol (8:2) extract of the leaves of Eucalyptus loxophleba ssp. lissophloia. The structures of new compounds were established by comprehensive spectral analysis and by comparison of their NMR data with those of related compounds in the literature. All the isolated compounds were evaluated for anti-leishmanial activity against promastigotes of Leishmania donovani.     

Allelopathy assessments for the environmental biosafety of the salt-tolerant transgenic Eucalyptus camaldulensis, genotypes codA12-5B, codA 12-5C, and codA 20C

Allelopathy tests were conducted on salt-tolerant transgenic eucalyptus trees conferring bacterial codA gene in the designated net-house conditions under Type II use (contained use) of the Japanese law on environmental biosafety aiming for Type I (field use) application. Three transgenic and corresponding nontransgenic genotypes were employed for four different tests: (1) sandwich bioassay; (2) soil germination method; (3) gas chromatography (GC) for volatile substances from the plants; and (4) high-performance liquid chromatography (HPLC) on phenolic compounds from fresh leaves, which are the primary allelopathic substances on the species. The simple approaches, the bioassays, indicated no significant difference between the transgenic and nongenetically modified genotypes. There was no qualitative difference between the transgenic and nontransgenic lines by GC or HPLC. Absence of any quantitative difference was suggested by repetitive examination and subsequent analysis of variance assessments with the chromatographic methods and bioassays. Moreover, it was also indicated that bioassays should be the primary assessment method for allelopathy in considering the simplicity, speed, low cost, and reproducibility of these methods. Overall, substantial equivalence was considered on the three transgenic genotypes with codA gene when compared with the nontransgenic Eucalyptus camaldulensis lines. The experiments supported the application to isolated field testing of the transgenic Eucalyptus camaldulensis genotypes as the first case and experience in Japanese regulatory approval processes Type I Use for the deliberate release to the environment.     

Effects of <Emphasis Type="Italic">Ips typographus</Emphasis> (L.) damage on litter quality and decomposition rates of Oriental Spruce [<Emphasis Type="Italic">Picea Orientalis</Emphasis> (L.) Link.] in Hatila Valley National Park,Turkey

This study investigated the effects of Ips typographus (L.) damage on initial litter quality parameters and subsequent decomposition rates of oriental spruce tree species [Picea orientalis (L.) Link]. The needle litter was collected from highly damaged, moderately damaged and control stands on two aspects (north and south) and two slope position (top and bottom) on each aspect. The litter was analyzed for initial total carbon, lignin and nutrient (nitrogen, phosphorus, potassium, calcium, magnesium and manganese) concentrations. The variability in nitrogen and calcium concentrations and ratios of C:N, lignin:N and lignin:Ca was significantly affected by the insect damaged levels. While nitrogen concentrations in needle litter increased with increasing insect damage (and consequently the ratios of C:N and lignin:N decreased), calcium concentrations decreased (and consequently the ratio of lignin:Ca increased). Aspect and slope positions explained most of the variability in carbon, lignin, phosphorus, potassium, magnesium and manganese concentrations and lignin:P ratio between all studied stands. Litter decomposition was studied in the field using the litterbag technique. The litter from highly damaged stands showed highest decomposition rates followed by moderately damaged and control stands. The mass loss rates were significantly positively correlated with initial nitrogen concentration and negatively with C:N and lignin:N ratios. The effects of microclimate resulting from canopy damage on litter decomposition was also examined at the same time using standard litter with the same litter quality parameters, but they showed no significant differences among the insect damage levels indicating that alteration of the litter quality parameters produced by I. typographus damage played a more important role than altered microclimate in controlling needle litter decomposition rates. However, changes in microclimate factors due to topography influenced decomposition rates.     

Heartwood extractives from the Amazonian trees <Emphasis Type="Italic">Dipteryx odorata,Hymenaea courbaril</Emphasis>, and <Emphasis Type="Italic">Astronium lecointei</Emphasis> and their antioxidant activities

Heartwood extracts from Amazonian trees cumaru-ferro (Dipteryx odorata), jatoba (Hymenaea courbaril), and guarita (Astronium lecointei) exhibit antioxidant activities comparable with that of α-tocopherol, a well-known antioxidant. This article reports the characterization of the antioxidant compounds in the extracts of the three heartwoods. Silica gel column chromatography of the cumaru-ferro EtOAc extract yielded (−)-(3R)-7,2′,3′-trihydroxy-4′-methoxyisoflavan and (+)-(3R)-8,2′,3′-trihydroxy-7,4′-dimethoxyisoflavan. Silica gel column chromatography followed by preparative high-performance liquid chromatography of the jatoba EtOAc extract yielded (−)-fisetinidol and (+)-trans-taxifolin. Chemical structures were assigned using electron-ionization mass spectrometry, ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy including nuclear Overhauser effect spectroscopy (NOESY), as well as optical rotation and circular dichroism. Gas chromatography-mass spectrometry demonstrated that the isolated compounds were predominant in the EtOAc extracts. In the guarita EtOAc extract, catechin and gallic acid were identified by comparing their retention times and mass fragmentation patterns with those of authentic samples. Antioxidant activity determined by the 1,1-diphenyl-2-picrylhydrazyl assay demonstrated that all these compounds had activities comparable with that of α-tocopherol. Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007     

Chemical constituents of Tolpis species

Phytochemical research of two Tolpis species, T. webbii and T. sp., led to the isolation of three new compounds: 2,4′-dihydroxy-4-methoxybenzophenone (1) and the triterpenes 21α, 22α-epoxy-20α-hydroxy-20(30)-dihydrotaraxasterol (2) and 3β-hydroxytaraxaster-20-en-30-oic acid (3) together with 16 known compounds. The structures of the new compounds were elucidated by means of extensive IR, NMR, MS and X-ray analysis and by comparison of data reported in the literature.     

A new belamcandaquinone from the seeds of Iris bungei Maxim

A novel dimeric 1,4-benzoquinone and resorcinol derivative, Belamcandaquinone N (1), and two known compounds, 3-hydroxyirisquinone (2) and 5-[(Z)-10-heptadecenyl] resorcinol (3), were isolated from the seeds of Iris bungei Maxim. Their structures were elucidated by spectroscopic methods and comparing with literature data of known compounds. These compounds showed remarkable cytotoxic activity against RM-1 cell lines.     

Extracellular peroxidase activity at the hyphal tips of the white-rot fungus Phanerochaete crassa WD1694

The white-rot fungus Phanerochaete crassa WD1694 was cultivated and peroxidase activity staining was performed to determine the sites at which the extracellular peroxidase reaction actually occurs in vivo. Although the ligninolytic peroxidases were found in the culture filtrates, the culture medium did not show a color reaction. However, a particularly strong color reaction was observed on the hyphal tips. Visible spectra and absorbance of the staining were analyzed by microspectrophotometry, and the catalytic rates of the peroxidase reaction at the hyphal tips were calculated. The estimated catalytic rate of the peroxidase reaction at the hyphal tips peaked at 794 μM/min, expressed as the consumption rate of H₂O₂, on day 3 of the cultivation. Analysis of the extracellular enzyme eluted with 0.1% Tween 80 from the mycelium revealed that manganese peroxidase accounted for 89% of all the peroxidase activity measured. The results clearly showed the existence of the concentrated manganese peroxidase reaction around the hyphal tips of the organism.     

Formation and chemical structures of acid-soluble lignin II: reaction of aromatic nuclei model compounds with xylan in the presence of a counterpart for condensation,and behavior of lignin model compounds with guaiacyl and syringyl nuclei in 72% sulfuric acid

To elucidate the formation and chemical structures of water-soluble material in acid-soluble lignin (ASL), lignin aromatic nuclei model compounds of creosol (I) and 5-methoxycreosol (II) were reacted with xylose or xylan in the presence of apocynol as a counterpart for condensation in 72% sulfuric acid (SA). The reaction of I gave mainly condensation product. However, the condensation reaction of II with apocynol was suppressed because of steric hindrance from the methoxyl group, and II yielded a C-xyloside after refluxing in 3% SA together with condensation products. To obtain information on CHCl₃-soluble material in ASL, model compounds of arylglycerol--aryl ethers with guaiacyl (VIII) and syringyl (X) nuclei were treated by the Klason procedure. VIII gave only insoluble polymerized product, while X gave insoluble polymerized product and CHCl₃-soluble low molecular weight products, which were dissolved in 3% SA. These results prove earlier views that water-soluble material in ASL consists of condensation products formed from syringyl lignin and monosaccharide units in hemicellulose. In addition, the CHCl₃-soluble material in ASL appears to be composed of low molecular weight degradation products from SA treatment of Klason lignin with the syringyl nucleus.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 and at the 47th Lignin Symposium, Fukuoka, October 2002, and was reviewed in Mokuzai Gakkaishi (2002) 48:55–62     

Abietane-type and labdane-type diterpenoids from the cones of Chamaecyparis obtusa

A novel compound, 8(17),12E,14-labdatrien-19-al (trans-communal), was isolated from ethyl acetate extract of young cones of hinoki (Chamaecyparis obtusa Endl.). The chemical structure of the compound was determined mainly with various nuclear magnetic resonance spectral techniques. Its stereochemistry was determined by derivation to a known compound,trans-communol. In addition to this compound, four known compounds — ferruginol, chamaecydin, 12-hydroxy-6,7-seco-abieta-8,l 1,13-triene-6,7-dial, and frans-communic acid — were isolated. All isolated compounds were subjected to an antifeedant bioassay against the pest insectSpodoptera litura. Results of the bioassay showed that chamaecydin and 12-hydroxy-6,7-seco-abieta-8,11,13-triene-6,7-dial had antifeedant activity.Part of this report was presented at 45th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1995     

Polyethylene degradation by lignin-degrading fungi and manganese peroxidase

Degradation of high-molecular-weight polyethylene membrane by lignin-degrading fungi, IZU-154, Phanerochaete chrysosporium, and Trametes versicolor, was investigated under various nutritional conditions. IZU-154 showed the most significant polyethylene degradation among the three lignin-degrading fungi under nitrogen- or carbon-limited culture conditions. Furthermore, for T. versicolor and P. chrysosporium, the addition of Mn(II) into nitrogen- or carbon-limited culture medium enhanced polyethylene degradation. These results suggest that polyethylene degradation is related to ligninolytic activity of lignin-degrading fungi. Treatment of polyethylene membrane with partially purified manganese peroxidase (MnP) caused significant degradation in the presence of Tween 80, Mn(II), and Mn(III) chelator. This result demonstrates that MnP is the key enzyme in polyethylene degradation by lignin-degrading fungi.This study was presented in part at the 9th International Symposium on Wood and Pulping Chemistry, Montreal, Canada, June 9–12, 1997     

Decolorization of kraft pulp bleaching effluent by a newly isolated fungus, Geotrichum candidum Dec 1

Kraft pulp bleaching effluent supplemented with glucose was decolorized by a newly isolated fungusGeotrichum candidum Dec 1 (Dec 1) that showed a wide decolorizing spectrum to synthetic dyes. When the glucose concentration in the effluent was 30 g/l, the color removal and the reduction of absorbable organic halogens were 78% and 43% after 7 days culture, respectively. The average molecular weight of colored substances measured by gel filtration chromatography was lowered to less than 3000 from 5600 after 7 days culture. As the contribution of extracellular enzymes such as peroxidase (DyP), manganese peroxidase, and laccase to the decolorization of the kraft pulp bleaching effluent was small, Dec 1 appears to have a different mechanism of decolorizing kraft pulp bleaching effluent when compared with enzymes used to decolorize synthetic dyes.     

Biobleaching of unbleached and oxygen-bleached hardwood kraft pulp by culture filtrate containing manganese peroxidase and lignin peroxidase fromPhanerochaete chrysosporium

Unbleached and oxygen-bleached hardwood kraft pulp (UKP and OKP), respectively, were bleached with a culture filtrate containing manganese peroxidase (MnP) and lignin peroxidase (LiP) fromPhanerochaete chrysosporium Burds. The brightness increases of UKP upon biobleaching with the culture filtrate with and without MnSO₄ were the same. The brightness increase of OKP with MnSO₄ decreased to about half that seen without MnSO₄. Changes in the brightness of UKP and OKP by treatment with the culture filtrate were determined. The brightness increased sharply by about eight points during the first 3h. The 3-h treatment was repeated seven times. The brightness increased linearly with the bleaching of UKP. On bleaching of OKP, the brightness increased slowly and stopped at about 78%.Part of this report was presented at the 62nd Pulp and Paper Research Conference of the Japan Tappi, Tokyo, June 1995     

Antimicrobial activity against <Emphasis Type="Italic">Streptococcus sobrinus</Emphasis> and glucosyltransferase inhibitory activity of taxifolin and some flavanonol rhamnosides from kempas (<Emphasis Type="Italic">Koompassia malaccensis</Emphasis>) extracts

Twenty plant materials collected from the islands of Java and Kalimantan in Indonesia were extracted with 50% aqueous ethanol (crude extract). The crude extracts were assayed for antimicrobial activities against Streptococcus sobrinus and for glucosyltransferase (GTase) inhibition. Fourteen extracts inhibited the growth of S. sobrinus by more than 50% and six extracts inhibited GTase activity by more than 50% at a concentration of 100 μg/ml. Koompassia malaccensis (kempas) extracts showed 90% depression of S. sobrinus growth and 80% inhibition of GTase activity at a concentration of 100 μg/ml. Kempas crude extracts were subjected to column chromatography using Sephadex LH-20 and then preparative high-performance liquid chromatography to isolate four compounds A, B, C, and D. These compounds were identified as taxifolin and the flavanonol rhamnoside isomers neoastilbin, astilbin, and isoastilbin, respectively, from ¹H and ¹³C nuclear magnetic resonance (NMR) spectra and other two-dimensional NMR techniques (COSY, HMBC, and HMQC). Each compound depressed the growth of S. sobrinus over a concentration range of 9.3242.7 μg/ml and showed GTase inhibitory activity with IC₅₀ values in the range 27.4–57.3 μg/ml. Taxifolin and flavanonol rhamnoside isomers isolated for the first time from kempas could be potent compounds for preventing dental caries. Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society Conference, Hiroshima, 2007     

Performance of two <Emphasis Type="Italic">Trichogramma</Emphasis><Emphasis Type="Italic">brassicae</Emphasis> strains under greenhouse and field conditions for biocontrol of the silver Y moth in spinach cultures

The suitability of Trichogramma brassicae Bezd. (Hymenoptera: Trichogrammatidae) to control the silver Y moth, Autographa gamma (L.) (Lepidoptera: Noctuidae) in spinach was investigated under greenhouse and field conditions. Two strains of T. brassicae were selected to study host searching efficiency and dispersal ability of the wasps on spinach. The experiments were conducted with defined release densities. The results show that T. brassicae strain I failed to locate host eggs in all experiments. In contrast, T. brassicae strain II females were able to locate 37% of the exposed egg clusters in the greenhouse within 48 h. Individuals colonised rapidly at least an area of 0.25 m². At distances up to 26 cm to the release point of the T. brassicae females, parasitization rate was 100%. Moreover, under field conditions silver Y moth eggs were exposed two times for 48 h on 12 experimental plots of 100 m² in two spinach fields. During the first exposure interval, i.e. 4 days after mass release of T. brassicae strain II, overall parasitization rates reached 20% on both fields. Furthermore parasitization rates still reached 16 and 19% during the second exposure interval, i.e. 9 days after natural enemy release, indicating a constant Trichogramma activity over time. Parasitization rates were highest in the close vicinity of the release point, i.e. 86%, whereas 6.5 m away the mean parasitization rate decreased to 3%. In conclusion results indicate a high potential of T. brassicae strain II as antagonist of A. gamma. Nevertheless the dispersal ability of T. brassicae strain II was limited, but adjustment of release densities and techniques might compensate this disadvantage.