Effects of heartwood extractive fractions of Thuja plicata and Chamaecyparis nootkatensis on wood degradation by termites or fungi

The effect of selective removal of extractives on termite or decay resistance was assessed with matched samples of Thuja plicata Donn ex D. Don and Chamaecyparis nootkatensis (D.Don) Spach heartwood. Samples were extracted using a variety of solvents and then exposed to the subterranean termite Coptotermes formosanus Shiraki in a no-choice feeding test or to the brown-rot fungus Postia placenta (Fr.) M. Larsen & Lombard in a soil bottle test. At the same time, the effect of naturally occurring variations in heartwood extractives on termite or decay resistance was evaluated by testing samples from the inner and outer heartwood of five trees of each species against C. formosanus and P. placenta and analyzing matched wood samples for their extractive content. The results suggest that the methanol-soluble extractives in T. plicata and C. nootkatensis play an important role in heartwood resistance to attack by C. formosanus and P. placenta. Total methanol-soluble extractive content of the heartwood was positively correlated with both termite and decay resistance; however, there was much unexplained variation and levels of individual extractive components were only weakly correlated with one another. Further studies are under way to develop a better understanding of the relationships between individual extractive levels and performance.     

Effects of plantation location and population on the seasonal freezing tolerance of yellow-cedar (Chamaecyparis nootkatensis) stecklings

Two years after planting, five populations of yellow-cedar (Chamaecyparis nootkatensis (D.Don) Spach) stecklings (rooted cuttings) at two latitudes and two elevations were tested for freezing tolerance through the winter by the freeze-induced electrolyte leakage method. There were few significant differences in freezing damage among the five populations. Freezing tolerance closely followed trends in daily mean temperature. At the southern latitude sites, high elevation stecklings were less damaged by freezing than low elevation stecklings in the autumn and late spring. No consistent elevational differences in freezing tolerance of stecklings were observed at the northern latitude sites.     

Seedling growth and establishment in natural stands of yellow-cedar (Chamaecyparis nootkatensis) seedlings derived from the use of modified seed dormancy-breaking treatments

Following dispersal from the parent tree, seeds of yellow-cedar (Chamaecyparis nootkatensis[D. Don] Spach) exhibit low germination, primarily as a result of coat-imposed dormancy. Dormancy of the mature (intact) seed is effectively terminated by traditional warm/cold treatments. A chemical treatment using the anaesthetic 1-propanol combined with a three day warm water soak (30 °C), a two day GA₃ treatment and 60 d of moist chilling not only promotes high germinability of yellow-cedar seeds, but also elicits vigorous post-germinative growth following seedling emergence under nursery greenhouse conditions. Here we compare the effectiveness of the more traditional warm/cold treatments with the chemical treatment in terms of their capacity to elicit vigorous growth and establishment in natural stands following transplant of seedlings from a nursery greenhouse environment. Two seed lots (42313 and 43697) and open-pollinated seed from parent trees 13-6 and 19-8 showed equivalent seedling growth in natural stands following the chemical treatment and two traditional warm/cold treatments typically used for dormancy breakage by the forest industry and by the Ministry of Forests in British Columbia. The chemical protocol offers the advantage of reducing the time required to break seed dormancy. We have now demonstrated that it yields seedlings that exhibit vigorous growth and are capable of withstanding the vagaries of the environment.     

Anti-inflammatory activity of (+)-usnic acid.

(+)-Usnic acid, isolated from the lichen Roccella montagnei, showed a dose-dependent anti-inflammatory activity when tested on rats, employing acute and chronic models.     

Chemical composition and antimicrobial activity of Chamaecyparis obtusa leaf essential oil

The essential oil obtained from the leaves of Chamaecyparis obtusa was analyzed by GC and GC-MS. alpha-Terpinyl acetate, sabinene, isobornyl acetate and limonene were found to be the major components. The oil showed relatively strong antibacterial activities against Gram (+) bacteria and some fungi.     

In vitro antifungal activity of phenylheptatriyne from Bidens cernua L. against yeasts

In vitro antifungal activity of phenylheptatriyne from Bidens cernua L. (Asteraceae) was studied using broth macrodilution method against 125 strains of yeasts including 104 clinical and other isolates of Candida spp. (C. albicans, C. krusei, C. tropicalis, C. guilliermondii, C. parapsilosis, C. glabrata, C. inconspicua), 16 strains of basidiomycetous yeasts (Cryptococcus neoformans, C. albidus, Trichosporon cutaneum, Rhodotorula glutinis) and five standard reference strains of Candida species. Phenylheptatriyne has shown significant activity against investigated strains, and the Minimal Inhibitory Concentrations for Candida spp. were determined as 12.5–50 µg/ml and for basidiomycetous yeasts as 12.5–100 µg/ml.     

Sesquiterpene lactones from Sonchus arvensis L. and their antibacterial activity against Streptococcus mutans ATCC 25175

Two new sesquiterpene lactones, 1β-sulfate-5α, 6βH-eudesma-3-en-12, 6α-olide (1) and 1β-(p-hydroxyphenyl acetyl)-15-O-β-d-glucopyranosyl-5α, 6βH-eudesma-3-en-12, 6α-olide (2) were isolated from Sonchus arvensis L. (Asteraceae), together with eight known compounds. Their structures were elucidated through spectroscopic and chemical methods. They were evaluated for antibacterial activity. Among them, compounds 1 and 7 exhibited antibacterial activity against oral pathogen Streptococcus mutans ATCC 25175 with MIC values of 15.6 and 62.5 µg/ml, respectively.     

Antifungal compounds from turmeric and nutmeg with activity against plant pathogens

The antifungal activity of twenty-two common spices was evaluated against plant pathogens using direct-bioautography coupled Colletotrichum bioassays. Turmeric, nutmeg, ginger, clove, oregano, cinnamon, anise, fennel, basil, black cumin, and black pepper showed antifungal activity against the plant pathogens Colletotrichum acutatum, Colletotrichum fragariae, and Colletotrichum gloeosporioides. Among the active extracts, turmeric and nutmeg were the most active and were chosen for further investigation. The bioassay-guided fractionation led to the isolation of three compounds from turmeric (1–3) and three compounds from nutmeg (4–6). Their chemical structures were elucidated by spectroscopic analysis including HR-MS, 1D, and 2D NMR as curcumin (1), demethoxycurcumin (2) and bisdemethoxy-curcumin (3), erythro-(7R,8R)-Δ^8′-4,7-dihydroxy-3,3′,5′-trimethoxy-8-O-4′-neolignan (4), erythro-(7R,8R)-Δ8′-7-acetoxy-3,4,3′,5′-tetra-methoxy-8-O-4′-neolignan (5), and 5-hydroxy-eugenol (6). The isolated compounds were subsequently evaluated using a 96-well microbioassay against plant pathogens. At 30 μM, compounds 2 and 3 possessed the most antifungal activity against Phomopsis obscurans and Phomopsis viticola, respectively.     

Tree-to-tree and clone-to-clone variations of monoterpenes emitted from needles of hinoki (Chamaecyparis obtusa)

Variations in the composition of low boiling point (LBP) monoterpenes emitted from needle samples of 150 hinoki (Chamaecyparis obtuse) trees (30 strains, each with five clones) native to Shimane Prefecture, Japan, were investigated using a headspace technique. The assays revealed considerable proportional variations especially in the amount of sabinene, which ranged from 24% to 78% of the total LBP monoterpenes. The proportions of α-pinene, myrcene, and limonene negatively correlated with that of sabinene overall. In particular, the proportion of limonene showed clear negative correlation with that of sabinene (r = −0.98). Differences in the proportion of sabinene among five clones in each strain were less than 15% in 22 out of 30 strains, indicating that monoterpene composition is constitutively steady in most strains. In a few strains, however, considerable variation in the composition was observed among clones.     

Inhibitory activity of homoisoflavonoids from Caesalpinia sappan against Beauveria bassiana

Four homoisoflavonoids, 4-O-methylsappanol (1), protosappanin A (2), brazilin (3) and caeasalpin J (4), isolated from Caesalpinia sappan, were tested for inhibitory activity against Beauveria bassiana. Compound 1 showed activity against this fungus.     

Xanthone isolated from Securidaca longependunculata with activity against erectile dysfunction

1,7-Dimethoxy-2-hydroxy-xanthone and 1,4-dihydroxy-7-methoxy-xanthone isolated from Securidaca longependunculata were tested for their activity on rabbit corpus cavernosum in vitro. Only the former relaxed the corpus cavernosum by 63% at 1.8 x 10(-5) mg/ml.     

Antibacterial activity of xanthorrhizol from Curcuma xanthorrhiza against oral pathogens

The antibacterial activity of xanthorrhizol, isolated from the methanol extract of Curcuma xanthorrhiza roots, was evaluated against oral microorganisms in comparison with chlorhexidine.     

Ethyl p-methoxycinnamate isolated from a traditional anti-tuberculosis medicinal herb inhibits drug resistant strains of Mycobacterium tuberculosis in vitro

Many plants are used in Ayurveda for the treatment of tuberculosis. Our aim was to examine if these plants possess any specific molecule that inhibits Mycobacterium tuberculosis. One of them, Kaempferia galanga, yielded an anti-TB molecule, ethyl p-methoxycinnamate (EPMC). By resazurin microtitre assay (REMA), EPMC was shown to inhibit M. tuberculosis H37Ra, H37Rv, drug susceptible and multidrug resistant (MDR) clinical isolates (MIC 0.242-0.485 mM). No cross resistance was observed to any standard anti-TB drugs in the MDR strains. The compound did not inhibit any prototype bacteria tested. EPMC seems to be a potential anti-TB lead molecule.     

引种台湾用材树种红桧、光蜡树苗木繁育试验研究

通过研究扦插育苗、种子育苗等一系列指标,比较了台湾红桧与福建柏、台湾光蜡树与白蜡树的育苗效果,结果表明:当用ABT处理时,引进树种红桧的扦插成活率均高于福建柏;光蜡树的成活率均高于白蜡树,3种浓度下,台湾红桧和福建柏的成活率间差异均达到极显著水平;浓度为40×10-6mol·L-1和80×10-6mol·L-1时,光蜡树和白蜡树的成活率间差异达到极显著水平,浓度为120×10-6mol·L-1时,这种差异只能达到显著水平。用NAA处理时,红桧的扦插成活率亦高于福建柏,80×10-6mol·L-1浓度时,二者的差异可达到极显著水平,40×10-6mol·L-1和120×10-6mol·L-1浓度时,二者的差异只能达到显著水平;光蜡树和白蜡树的成活率均有不同程度的提高,80×10-6mol·L-1浓度时,二者的差异可达到极显著水平,40×10-6mol·L-1浓度时,二者的差异只能达到显著水平,而120×10-6mol·L-1浓度时,2树种间无显著性差异。红桧和福建柏的发芽率和苗高的差异均达到极显著水平,而成苗率的差异达到显著水平,苗径的差异不能达到显著性水平。光蜡树与白蜡树的成苗率和苗高的差异均可达到极显著水平,而发芽率和苗径的差异不能达到显著水平。     

Liquid culture and transformation of hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.)

Hinoki cypress (Chamaecyparis obtusa) is one of the most important timber resource forest trees in Japan. Because seed production from a seed orchard of hinoki cypress is not constant every year, micropropagation from a limited amount of material is useful. Up to now, the conventional tissue culture method using solid medium has been used. Here a new method using liquid culture in tubes rotated vertically is described. Shoot primordium of hinoki cypress was inoculated in Campbell and Durzan’s (CD) liquid medium containing different cytokinins (6-benzylaminopurine (BAP), Zeatin, thidiazurone (TDZ)), and the container tubes were rotated vertically around the axis at 2 times / min. Culture room temperature was 25°C and light condition was 16 h photoperiod per day of fluorescent lamps. Zeatin at 1μM concentration was the best for maintaining the shoot primordium production and TDZ induced callus on the surface of the shoot primordia. After shoot primordium multiplication in the liquid culture, they were transplanted to agar medium for shoot elongation. A high concentration of agar (up to 16 g/L) or AVF (anti vitrification factor from Dr. Nairn, 1995) was effective to prevent vitrification of the shoots. Transformation of shoot primordium was done using particle bombardment with vectors containingβ-glucuronidase (GUS) gene or herbicide resistance gene (bar). Positive result for transient transformation was observed with the histo-chemical study for transformation with GUS. Integration of a useful herbicidebar gene into the shoot primordium culture system was also tried and stably transformed plants were obtained. This is the first report of stable transformation of Japanese conifer using practically useful gene. The generous supply of AVF-B from Dr. B.J. Nairn, Tasman Forestry, NZ is also appreciated.     

Antifungal activity of Liriodenine from Michelia formosana heartwood against wood-rotting fungi

Wood-rotting fungi lead to great economic losses of lignocellulosic materials. The influence of extractives on the decay resistance of Michelia formosana wood and the antifungal activities of heartwood extract and its constituent against wood-rotting fungi were evaluated. Results revealed that extractives had a strong influence on the decay resistance of M. formosana heartwood. The unextracted heartwood block was resistant to fungi, while the extracted heartwood block was not. Antifungal activities of ethanolic extract from heartwood were assessed; results revealed that the ethanolic extract possessed good antifungal activity against wood-rotting fungi. The ethanolic extract was further separated into four fractions including n-hexane-soluble fraction, ethyl acetate-soluble fraction, n-butanol-soluble fraction, and water-soluble fraction. Among these fractions, the n-hexane-soluble fraction exhibited the best antifungal ability. An alkaloid, liriodenine, was isolated from the active n-hexane-soluble fraction. IC₅₀ values of liriodenine against the white-rot fungi Lenzites betulina and Trametes versicolor were 0.76 and 3.50?μg/mL, respectively. IC₅₀ values of liriodenine against the brown-rot fungi Laetiporus sulphureus, Gloeophyllum trabeum, and Fomitopsis pinicola were all lower than 2.0?μg/mL. Results indicated that liriodenine exhibited a broad spectrum of antifungal activity and great potential to develop as an environmentally benign fungicide for the preservation of lignocellulosic materials.     

Antimicrobial activity of 2-arylbenzofurans from Morus species against methicillin-resistant Staphylococcus aureus

Nine 2-arylbenzofurans isolated from Morus species were tested for their antimicrobial activities against methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), Micrococcus luteus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. Among these compounds, chalcomoracin (a leaf phytoalexine of mulberry tree) exhibited considerable antibacterial activity against MRSAs (MICs 0.78 μg/ml).     

Antifungal activity of essential oils isolated from Egyptian plants against wood decay fungi

The essential oils of eighteen Egyptian plants were extracted by hydrodistillation and their chemical compositions were analyzed by GC-MS. The antifungal activity of the isolated oils was evaluated against two wood decay fungi Hexagonia apiaria and Ganoderma lucidum in vitro. The essential oil of Artemisia monosperma showed the highest inhibitory effect against H. apiaria (EC₅₀ = 31 mg L^?1) and G. lucidum (EC₅₀ = 53 mg L^?1). The results of in vitro tests indicated that the essential oils of Cupressus sempervirens, Citrus limon, Thuja occidentalis, Schinus molle, A. monosperma and Pelargonium graveolens were the most potent inhibitors against both fungi. These six oils caused significant reduction of wood mass loss of Scots pine sapwood after 6 weeks of fungal exposure. The oil of C. limon revealed the highest reduction of wood mass loss caused by H. apiaria, while A. monosperma oil displayed the highest reduction of wood loss caused by G. lucidum. These results support the potential use of essential oils for wood protection against decay fungi.