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Lignans are major bioactive secondary metabolites, which are also formed in the heartwood (hW) of Taiwania (Taiwania cryptomerioides). Their biosynthesis pathways are complex and involve many enzymes and intermediates. To evaluate the extent of the genetic components leading to the variety of lignans in Taiwania hW, 35 Taiwania genotypes of four provenances were surveyed using the proton nuclear magnetic resonance (1H-NMR) and liquid chromatography-mass spectrometry (LC-MS) analyses. The metabolite profiles were statistically evaluated by principal component analysis (PCA) and the general linear model (GLM). The broad-sense heritability (H 2) was further evaluated by linear mixed model (LMM) analysis. It was demonstrated that the genetic factor is the major contributor to the abundance of lignans, though the environmental factor also has some effect on it. Among the metabolites detected by 1H-NMR, lignans were the major compounds that exhibited high a H 2 (0.52–0.82), which was further verified by LC-MS. The conclusion is that 1H-NMR spectroscopy is suitable for quick screenings, predictions and semi-quantitation of lignans. The high H 2 is also indicative of the lignan abundances as traits that can be genetically modified to achieve a significant wood quality improvement.

The objective of the present study is to evaluate the cytotoxicity of Taiwania cryptomerioides essential oil and its phytochemical on the Hep G2 cell line (human hepatocellular carcinoma). Bark essential oil has significant cytotoxicity to Hep G2 cells, and S3 fraction is the most active fraction in cytotoxicity to Hep G2 cells among the six fractions. The diterpenoid quinone, 6,7-dehydroroyleanone, was isolated from the active S3 fraction by bioassay-guided isolation. 6,7-Dehydroroyleanone exhibited significant cytotoxicity in Hep G2 cells, and the efficacy of 6,7-dehydroroyleanone was better than the positive control, etoposide. Apoptosis analysis of Hep G2 cells with different treatments was characterized via flow cytometry to confirm the cell death situation. Etoposide and 6,7-dehydroroyleanone could induce the apoptosis in Hep G2 cells using flow cytometric assay. Results revealed 6,7-dehydroroyleanone from T. cryptomerioides bark essential oil can be a potential phytochemical to develop the anticancer chemotherapeutic agent for the treatment of the human hepatocellular carcinoma.

Taiwania (Taiwania cryptomerioides Hayata) is an indigenous conifer species of Taiwan. Various secondary metabolites of Taiwania with diverse bioactivities have been identified, and lignans are especially abundant in the heartwood (hW). In the present study, the wood of this species was separated to cambium (Cam), sapwood (sW), transition zone (TZ) and hW and their transcriptomes were sequenced. Three pinoresinol-lariciresinol reductases (PLRs; designated TcPLR1, TcPLR2.2 and TcPLR3), which are responsible for lignan biosynthesis, were cloned and their expressions in wood tissues were detected. TcPLRs had higher expression levels in Cam and sW in RNA-seq and reverse transcriptase-polymerase chain reaction (RT-PCR) results. Liquid chromatography-mass spectrometry (LC-MS) analysis of the reaction products of TcPLRs revealed that TcPLR1 can reduce (+)-pinoresinol to lariciresinol, and both TcPLR2.2 and TcPLR3 could reduce (+)-pinoresinol to lariciresinol and secoisolariciresinol.

The heartwood of Taiwania (Taiwania cryptomerioides Hayata) has the excellent decay resistance and fascinating color qualities due to the accumulation of bioactive compounds. However, limited infor...

Biogenesis-inspired chemical research of the leaves of Taiwania cryptomerioides afforded four unprecedented dimeric diterpenes, featuring a tetracyclic [7. 75, 9. 4. 05, 10. 08, 9] octodecane core: taiwanoids A-D (1-4). The structures of these compounds were determined on the basis of comprehensive spectral analysis, chemical conversions and X-ray crystallography. A possible biosynthetic pathway for compounds 1-4 was proposed. Compounds 2 and 3 exerted a 5.37 and 6.26-fold potentiation effect on bortezmib (BTZ) susceptibility at a tested concentration of 20 μM, respectively.

Taiwania cryptomerioides is a monotypic species, and its terpenoid-rich property has been reported in recent years. To uncover monoterpene biosynthesis in T. cryptomerioides, this study used transcriptome mining to identify candidates with tentative monoterpene synthase activity. Along with the phylogenetic analysis and in vitro assay, two geraniol synthases (TcTPS13 and TcTPS14), a linalool synthase (TcTPS15), and a β-pinene synthase (TcTPS16), were functionally characterized. Via the comparison of catalytic residues, the Cys/Ser at region 1 might be crucial in determining the formation of α-pinene or β-pinene. In addition, the Cupressaceae monoterpene synthases were phylogenetically clustered together, they are unique and different from those of published conifer species. In summary, this study aimed to uncover the ambiguous monoterpenoid network in T. cryptomerioide, which would expand the landscape of monoterpene biosynthesis in Cupressaceae species.

Taiwania (Taiwania cryptomerioides Hayata) is one of the economically important tree species indigenous to Taiwan. Hundreds of secondary metabolites have been identified from its wood, bark, root, and needles with lignans as the dominant ones. This substance group contributes a lot to the color, durability, and bioactivities of Taiwaniana. The present paper is dedicated to the quantification of radial and longitudinal lignan distribution. The extractives begin to accumulate largely in the transition zone (TZ), and reach a maximum after finishing the heartwood (hW) formation. Both dibenzyl-γ-butyrolactone type and arylnaphthalide type lignans were found in sapwood (sW) except for the compound taiwanin A. Clearly, the heartwood formation of Taiwania differs from the hitherto known hW formation types and it is suggested to be denominated as Taiwania-type hW formation, where the biosynthesis of extractives begins in the sW and where their accumulation is clearly elevated in the TZ. A generalized biosynthesis scheme of Taiwanin is presented showing the putative relationships among the most important dimeric lignans that lead to the formation of taiwanin type lignans.

Background Hinokiol is a naturally occurring diterpenoid compound isolated from plants such as Taiwania cryptomerioides . Anti-oxidation, anti-cancer, and anti-inflammation effects of this compound have been reported. It is not yet known if hinokiol affects neurons or neuronal ion channel activities. We reported here that hinokiol inhibited voltage-gated Na + channels (VGSC) in neuronal cells and we characterized the mechanisms of block. Methods The effects of hinokiol on Na + channels were examined using the voltage-clamp (whole-cell mode) technique. Results VGSC was blocked by hinokiol in a concentration-dependent and state-dependent manner in neuroblastoma N2A cells: IC 50 are 11.3 and 37.4 μM in holding potentials of −70 and −100 mV, respectively. In the presence of hinokiol there was a 13-mV left shift in steady-state inactivation curves; however, activation gating was not altered. VGSC inhibition by hinokiol did not require channel opening and was thus considered to be closed-channel block. In the presence of hinokiol, since the degree of block did not enhance with stimulation frequency, block by hinokiol thus did not exhibit use-dependence. Recovery from channel inactivation was not significantly affected in the presence of hinokiol. In addition, hinokiol also inhibited VGSC of differentiated neuronal NG108-15 cells and rat hippocampal CA1 neurons. Conclusion Our results therefore suggest hinokiol inhibited VGSC in a closed-channel block manner and such inhibition involved intensification of channel inactivation.

We studied forests containing Taiwania cryptomerioides of various ages and habitats on the eastern slopes of the Gaoligong Mountains in terms of forest structure and composition, population structure (size, age), regeneration patterns, and persistence of the species in relation to their favored habitats. Taiwania thrives in unstable habitats on riverbanks in deep valleys, on steep slopes, on cliffs, on roadsides and by mountain paths at the altitudes of 1175-2500 m a.s.l. All these locations were subject to frequent landslides, whereas Taiwania was very rare at similar altitudes on stable gentle slopes or on mountain ridges free of major disturbances. The maximum age of Taiwania was calculated to be c. 1,872 yr, with 358 cm DBH (diameter at a height of 1.3 m) and 70 m high. The size and age classes of Taiwania in old-growth forests were multimodal, indicating that the regeneration varied by chance, depending on disturbances. In the old-growth forests where above-ground competition for light was intense, shade-intolerant and long-lived coniferous Taiwania became emergent (40–70 m), rising above a forest canopy comprised of more shade-tolerant evergreen broad-leaved trees. The reproduction of the species was mainly by means of minute wind-dispersed seeds falling into rock crevices on cliffs or a rocky forest floor, or on disturbed sites. These populations depended on disturbances or gap regeneration to survive. Taiwania gave way to evergreen broad-leaved tree species of Lithocarpus, Cyclobalanopsis, and Manglietia, and to other conifers such as Tsuga dumosa, where landslides were infrequent. Our results provide insights into the ecological characteristics and survival mechanisms of this East Asian paleoendemic conifer, and contribute to our understanding of the differentiation of forests.

The genetic variation in wood property and growth of Taiwania (Taiwania cryptomerioides) was investigated at two test sites in the same general location, but one at 1200 m (LK20) and another at 1900 m (LK24). A rangewide sample of 48 open-pollinated families in Taiwan was involved. The test plantations were 16 years old when the wood property data were collected. Traits studied include wood specific gravity, tracheid length, ring width. DBH at ages13, 16, and 22 and height at age 13 were also analyzed. Site environment had a dominant effect on growth and wood density, but showed little interaction with family. The site effect was evident in large between-site differences in means, range of family means, and size of family variance components and heritability estimates. These differences are attributable to the site characteristics of LK24 (high elevation, upper slope near a mountain crest) and an unfavourable local climate. Taiwania is fast growing and produces quality wood, and is also an interesting species from the perspective of evolutionary biology. Protection of its genetic variability should be a priority to be managed. We propose that the existing five progeny tests be protected since these tests well-represent the genetic variability of the species in Taiwan.

The first asymmetric total synthesis of (+)-taiwaniaquinol D and (−)-taiwaniaquinone D isolated from Taiwania cryptomerioides was attained by using the intramolecular asymmetric Heck reaction. The reaction provided a tricyclic intermediate that would be available for the asymmetric total synthesis of various abeo-abietane-type diterpenoids.

Summary Taiwania (Taiwania cryptomerioides), which grows mostly in Taiwan, is a highly valued species and consequently requires intensive management. We developed diameter distribution models that incorporate the effects of thinning at different intensities at different ages to assist forest managers to meet their management objectives. Our data consist of tree diameter at breast height measurements from four thinning treatments (control, light, medium, and heavy thinning) at ages 6, 11, 17, 25, 31 and 40 y. We entertained four potential functions for our distribution model: a truncated normal, a generalised Weibull, a four-parameter logit-logistic (LL), and a two-parameter logit-logistic. The four-parameter LL fonction resulted in the best diameter distribution model for our data. We then modelled the parameters of the fitted LL diameter distribution models as a function of time and thinning regime. This allows the diameter distribution to be reconstructed for various combinations of ages and thinning re...

The genetic diversity and differentiation of five populations of Taiwania cryptomerioides Hayata in mainland China were investigated using inter-simple sequence repeats (ISSR). In comparison with other coniferous species, T. cryptomerioides from mainland China possesses little genetic variation, particularly at the level of individual populations (the percentage of polymorphic loci, Nei’s gene diversity and Shannon’s indices of diversity at the species and population levels are 38.02%, 0.1326, 0.1986 and 9.27%, 0.035, 0.0518 respectively). In contrast, the level of population differentiation is much higher (GST: 0.7269; Shannon’s genetic differentiation: 0.7392; Hickory è B: 0.668; AMOVA genetic differentiation: 72.37%). The genetic divergence of pairs of populations was not significantly correlated with the geographical distance separating them. Current patterns of genetic variation were related to biogeographic history and the small population size. On the basis of these findings, we discuss the development of conservation strategies for this endangered species.

Four new podocarpane-type trinorditerpenenes, (5 beta,10 alpha)-12,13-dihydroxypodocarpa-8,11,13-trien-3-one (1), (5 beta,10 alpha)-12-hydroxy-13-methoxypodocarpa-8,11,13-trien-3-one (2), (5 beta,10 alpha)-13-hydroxy-12-methoxypodocarpa-8,11,13-trien-3-one (3), and (3 alpha,5 beta,10 alpha)-13-methoxypodocarpa-8,11,13-triene-3,12-diol (4), together with four known diterpenes, 12-hydroxy-13-methylpodocarpa-8,11,13-trien-3-one (5), spruceanol (6), ent-3 alpha-hydroxypimara-8(14),15-dien-12-one (7), and ent-3 beta,14 alpha-hydroxypimara-7,9(11),15-triene-12-one (8), were isolated from the twigs and leaves of Aleurites moluccana. Their structures were elucidated by means of comprehensive spectroscopic analyses, including NMR and MS. Except 8, all compounds were evaluated for their cytotoxicity; compound 4 exhibited moderate inhibitory activity against Raji cells with an IC50 value of 4.24 mu g/ml.

Six new cadinane-type sesquiterpenes, (1β,4β,5α,10α)-1,4-epoxymuurolan-5-ol (1), (4α,10β)-4,10-dihydroxycadin-1(6)-en-5-one (2), (2β,3α,4β,6β)-2,3-dihydroxycadin-1(10)-en-5-one (3), (2β,3α)-α-corocalene-2,3-diol (4), (7S)-α-calacoren-14-ol (5), and (8β,9β,10β)-8,9-epoxycalamenene-3,10-diol (6) together with one known compound, (8β,9β,10β)-8,9-epoxycalamenen-10-ol (7), were isolated from the roots of Taiwania cryptomerioides. The structures of the new constituents were essentially elucidated by spectral evidence.

Taiwania (Taiwania cryptomerioides Hay) is an important timber species in Taiwan. Growth in generally improved trees under intense silvicultural practice is so rapid that rotations or the practice of thinning trees may be as short as 20–30 years. Thus, the wood properties of young plantation trees need to be characterized to effectively use this resource. The effects of different thinning and pruning methods on the compressive strength parallel to grain of young Taiwania trees were explored. Average compressive strengths with various thinning treatments revealed the trend of no thinning > medium thinning > heavy thinning and in the pruning treatments showed the trend of medium pruning > no pruning > heavy pruning. However, most results showed no statistically significant differences among thinning and pruning treatments.

The fractometer is a device that breaks a radial increment core along the fiber for the measurement of crushing strength, which is a direct wood quality indicator for structural lumber. In this study, the crushing strength of Taiwania (Taiwania cryptomerioides Hay) trees using the fractometer was investigated and the data were used to determine the position of demarcation between juvenile and mature wood. Segmented regression and variance component analysis were used to estimate the demarcation position. With increasing cambium age, the core wood improves the crushing strength in the outer wood area. Within-tree variations in wood properties were greater than between-tree variations. In this experiment, the position of demarcation between juvenile and mature wood occurred at an approximate distance of 10.8cm to 13.2cm from the pith at about 18–20 years of cambium age.

Six new norlignans, named sequosempervirins B-G (1-6), together with three known norlignans, agatharesinol (7), agatharesinol acetonide (8), and sugiresinol (9), were isolated from the branches and leaves of Sequoia sempervirens. Their structures were determined mainly by high-resolution mass spectroscopy (HR-MS), and various 1D- and 2D-NMR methods, as well as, in the case of 1, by means of X-ray diffraction. Compound 8 showed anticancer activity towards the A549 non-small-cell lung-cancer cell line (IC50 = 27.1 microM). The acetone extract of S. sempervirens was found to be antifungal towards Candida glabrata (IC50 = 15.98 microg/ml), and both the acetone and MeOH extracts inhibited the proteolytic activity of cathepsin B (IC50 = 4.58 and 5.49 microg/ml, resp.).

Four new diterpenes, 3-oxosaprorthoquinone (1), 3-oxomicrostegiol (2), 3-oxoisotaxodione (3), and taiwaninal (4), together with two known compounds, 3-oxosapriparaquinone (5) and 6-dehydrohinokiol (6), were isolated from the roots of Taiwania cryptomerioides. The structures of 1-4 were principle elucidated based on spectral evidence.

This study investigated the effects of various thinning and pruning methods on the knots (number and size) and lumber recovery from Taiwania (Taiwania cryptomerioides Hay.) plantation trees. The results showed that heavy thinning caused more knots and larger-diameter knots than medium or no thinning; moreover, pruning caused fewer numbers of knots and smaller-diameter knots than no pruning. Better-quality Taiwania trees occurred with the no-thinning/no-pruning treatments, as shown by analyzing the knots, although the results also showed that the healing process seemed to have produced not completely clear wood during the 9 years after the pruning treatment. The thinning intensity slightly enhanced the lumber recovery of logs. Pruning did not affect lumber recovery from taiwania trees and logs. Thinning increased the lumber recovery per tree due to an increase in the diameter at breast height.

The effects of various thinning and pruning methods on the density profile and annual ring characteristics of Taiwania (Taiwania cryptomerioides Hay.) using the drilling resistance technique were investigated. The results showed that thinning caused wider annual rings than medium thinning or no thinning, and pruning caused narrower annual rings than no pruning. Moreover, the thinning treatment affected annual rings more effectively than the pruning treatment. The average ring density after the thinning treatments showed a trend as follows: no thinning > medium > heavy. This indicates that thinning reduces the average ring density. The average ring density after the pruning treatments showed a trend as follows: medium > no pruning > heavy. However, the differences between thinning and no thinning were not statistically significant. The percentage of latewood in Taiwania after these three thinning and pruning treatments are shown. The results with silvicultural treatments have the order: medium > not treated > heavy, but there are no statistically significant differences among thinning, pruning, and thinning where pruning interactions were observed. Moreover, there were highly significant negative relations between the average ring width and the various ring densities for Taiwania, but the determination coefficients were small. In addition, there was a highly positively significant relation between the latewood percentage and latewood width.

Taiwania (Taiwania cryptomerioides Hayata), native to Taiwan, is one of the most economically important tree species grown there. In this article we summarize the current results of phytochemistry and bioactivity of Taiwania extracts, including antifungal, antitermite, antibacterial, and antimite activities as well as cytotoxicity against three tumor cells. The resources of Taiwania are also addressed.

Summary Nine abietane-type diterpenes were isolated from the heartwood of Taiwania cryptomerioides and their structures identified by spectral analyses. Among these nine compounds, six diterpenes were isolated for the first time from T. cryptomerioides, including 6,7-dehydroferruginol, 6α-hydroxysugiol, 5,6-dehydro-6-hydroxysugiol, 11-hydroxyferruginol, secoabietane dialdehyde and isohinokiol. We suggest that abietane-type diterpenes are the dominant diterpenes in the heartwood of T. cryptomerioides. A possible biosynthesis pathway is proposed. In addition, a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was performed to evaluate the antioxidant activity of these diterpenes. This study demonstrates that ferruginol exhibits the strongest antioxidant activity among the diterpenes isolated from T. cryptomerioides heartwood.

Antitermitic activity of Taiwania (Taiwania cryptomerioides Hayata) against Coptotermes formosanus Shiraki was demonstrated in laboratory tests. Blocks of sapwood and heartwood from T. cryptomerioides exhibited antitermitic activity. Bioassays revealed that heartwood essential oil exhibited the highest antitermitic activity, followed by sapwood essential oil and then the n-C6H14soluble fraction when tested at 10 mg/g. The order of termite mortality of three compounds purified from n-C6H14soluble extracts of heartwood was cedrol > α-cadinol > ferruginol. The termite resistance of T. cryptomerioides wood can be attributed to the termiticidal activity of cedrol and α-cadinol.

Summary The antifungal activity of cadinane skeletal sesquiterpenoids from Taiwania (Taiwania cryptomerioides Hayata) heartwood is demonstrated. Using spectral analyses, the absolute structures of three main cadinanes, T-cadinol, T-muurolol, and α-cadinol, all isolated from Taiwania with HPLC, were identified. The amount of these cadinanes was also quantified using GC. The results showed that the total amount of cadinanes extracted from heartwood with n-C6H14 was 6.49 mg per kg of wood. This was much more than the essential oils collected by water distillation from leaves (0.04 mg/kg), sapwood (0.36 mg/kg), or heartwood (1.77 mg/kg). Moreover, results obtained from the antifungal assays demonstrated that αcadinol exhibited the highest antifungal index for both Coriolus versicolor and Laetiporus sulphureus, followed by T-cadinol and T-muurolol. As a matter of fact, α-cadinol completely inhibited the growth of C. versicolor and L. sulphureus at the level as low as 100 ppm. Further comparison of the molecular configuration of these cadinanes reveals that cadinane skeletal sesquiterpenoids with an equatorial hydroxyl group at C-9 and a trans configuration at the ring junction, such as the case for α-cadinol, exhibited the strongest antifungal activity.

Summary One of the color substances, taiwanin A, was isolated from Taiwania (Taiwania cryptomerioides Hayata) heartwood. According to the 13C-NMR, 1H-NMR, HSQC, HMBC, and NOE difference spectroscopy analyses, the diene structure of taiwanin A was reconfirmed to be the trans-trans formulation. In addition, it was proven that deep orange crystalline taiwanin A changed to white and pale yellow compounds, taiwanin C and taiwanin E, after light irradiation. The conversion mechanism of taiwanin A into taiwanin C and taiwanin E is also proposed and discussed in this study.

In addition to eleven known lignans, eight new compounds including 8-hydroxypluviatolide, 5,8-dihydroxypluviatolide, two benzofuran-type neolignans, three lignans bearing oxy substituents at the C-2 positions and a γ-piperonylmethyl-γ-butenolide were isolated from the leaves of Taiwania cryptomerioides Hayata. Their structures were determined by spectroscopic methods.

Five new diterpenes and four uncommon sterols were isolated from the leaves of Taiwania cryptomerioides. Their structures were determined by chemical, spectroscopic and X-ray diffraction methods. The terpenes are 8,9-epoxy-7-oxoroyleanone methyl ether, 1,13,14-trihydroxypodocarpa-8,11,13-trien-7-one, 7α,8α-dihydroxylabda-13(16),14-dien-19-yl cis-4-hydroxycinnamate, 7α,8α-dihydroxylabda-13(16),14-dien-19-yl trans-4-hydroxycinnamate and beyer-15-en-18-carboxy β- d -glucopyranoside pentaacetate. The sterols, namely taiwaniasterols A-D, exhibit an uncommon skeleton of 6-5-6-5 fused rings.

Four [4+2] or [5+2] cycloadducts formed from trans -ozic acid and a diterpene or norditerpene quinone were isolated from the leaves of Taiwania cryptomerioides . Among them, the [4+2] cycloadduct (taiwaniadduct I) formed from trans -ozic acid and a norditerpene quinone underwent an intramolecular [2+2] cycloaddition on standing at room temperature. The structures of these cycloadducts were determined by spectral analyses and of one by X-ray crystallography. © 1997 Elsevier Science Ltd. All rights reserved

Seven new compounds were isolated from the leaves of Taiwania crypomerioides. Taiwaniaquinone D and taiwaniaquinone E are diterpenes having a six-five-six fused ring skeleton. Taiwaniadduct A is a [4 + 2] cycloaddition product of β-myrcene and taiwaniaquinone A. Taiwaniadduct B and taiwaniadduct C are isomers derived from [4 + 2] cycloadditions of trans-ozic acid and taiwaniaquinone A. Taiwaniadduct D is formally an ene reaction product of taiwaniadduct B. Taiwaniadduct E is a [5 + 2] cycloaddition product of taiwaniaquinone A and trans-ozic acid. The structure determination of these new compounds was based on spectral analyses and chemical transformation. A crystalline compound, prepared by bismethylation of taiwaniadduct D, was analysed by X-ray diffraction to establish the stereochemistry.

Two novel 3,4-secocadinane and 4,5-seco-8(7→6)-abeoguaiane skeletons, namely taiwaninones A ( 1 ) and B ( 2 ), together with khusinodiol ( 3 ) and 4β,6β-dihydroxy-1α,5β( H )-guai-9-ene ( 4 ) were isolated from the roots of Taiwania cryptomerioides . Their structures were elucidated by the spectral methods. The biotransformations of 1 and 2 were proposed from 3 and 4 , respectively.

Three new 5(6--7)abeoabietane diterpenes with the uncommon skeleton of fused 6-5-6 rings were isolated from the bark of Taiwania cryptomerioides designated as taiwaniaquinone F (8), taiwaniaquinol C (9) and taiwaniaquinol D (10). Meanwhile, two known compounds, taiwaniaquinones A (1) and D (4), were also obtained. Their structures were determined principally from spectral evidence.

The proportions of sapwood and heartwood of trees have significant impacts on various uses. Electric resistivity tomography (ERT) and corresponding electrical resistance (ER) value maps were examined in Japanese cedar (Cryptomeria japonica D. Don), Taiwania (Taiwania cryptomerioides Hayata), and Luanta fir (Cunninghamia konishii Hayata) trees. The position of the sapwood-heartwood demarcation was measured on incremental cores from living trees and the corresponding ER of the sapwood-heartwood boundary was acquired from the ER map. A positive significant relationship was found between the maximum ER plus minimum ER values (ERmax + ERmin) and ER of the sapwood-heartwood demarcation from the tomographic data. The position of the sapwood-heartwood demarcation was determined by corresponding ER, and the critical ER can be established by the ERmax + ERmin value of the tomographic data. The results from this study indicate that ERT technique can be used to determine the position of the sapwood-heartwood boundary and can serve as a methodology in undamaged living trees of Gymnosperm species.

Three quinone-type podocarpanes, 3β-hydroxy-13-methoxy-8, 12-podocarpadiene-11, 14-dione (1), 18-hydroxy-13-methoxy-8, 12-podocarpadiene-11, 14-dione (2), and 13-methoxy-8, 12-podocarpadiene-2, 11, 14-trione (3) were isolated from the bark of Taiwania cryptomerioides. Their structures were elucidated using spectral methods.

Four diterpenoid aldehydes and one norditerpenoid ketone having the uncommon skeleton of six-five-six fused-rings were isolated from the leaves of Taiwania crytomerioides .

Five new diterpenes and four uncommon sterols were isolated from the leaves of Taiwania cryptomerioides. Their structures were determined by chemical, spectroscopic and X-ray diffraction methods. The terpenes are 8,9-epoxy-7-oxoroyleanone methyl ether, 1,13,14-trihydroxypodocarpa-8,11,13-trien-7-one, 7α,8α-dihydroxylabda-13(16),14-dien-19-yl cis-4-hydroxycinnamate, 7α,8α-dihydroxylabda-13(16),14-dien-19-yl trans-4-hydroxycinnamate and beyer-15-en-18-carboxy β- d -glucopyranoside pentaacetate. The sterols, namely taiwaniasterols A-D, exhibit an uncommon skeleton of 6-5-6-5 fused rings.

Two novel 9,11- seco -11-norabietanes, namely taiwanlactones A ( 1 ) and B ( 2 ), together with 3β-hydroxysugiol ( 3 ) and 6α-hydroxysugiol ( 4 ), were isolated from the roots of Taiwania cryptomerioides . Their structures were elucidated through spectral studies. The absolute configuration of 1 was elucidated by a modified Mosher’s method. The biotransformation mechanisms of 1 and 2 were proposed.

Four diterpenoid aldehydes and one norditerpenoid ketone having the uncommon skeleton of six-five-six fused-rings were isolated from the leaves of Taiwania crytomerioides .

Five new cadinane-type sesquiterpenes, 15-acetoxy-T-muurolol (1), isokhusinodiol (2), cadin-10(14)-ene-4beta,5alpha-diol (3), cadinane-4beta,5alpha,10beta-triol (4), and muurolane-4beta,5beta,10beta-triol (5), together with five known compounds, T-cadinol (6), T-muurolol (7), alpha-cadinol (8), delta-cadinol (9), and khusinodiol (10), were isolated from the roots of Taiwania cryptomerioides. The structure of the new constituents were elucidated through chemical and spectral studies.

Five new 7-oxopodocarpane-type trinorditerpenes together with 1beta,13,14-trihydroxy-8,11,13-podocarpatrien-7-one ( 1) were isolated from the bark of Taiwania cryptomerioides. By using NMR and other spectral methods, the structures of five new compounds, 14-hydroxy-13-methoxy-8,11,13-podocarpatriene-3,7-dione ( 2), 1beta,14-dihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one ( 3), 13,14-dihydroxy-8,11,13-podocarpatriene-3,7-dione ( 4), 3beta,13,14-trihydroxy-8,11,13-podocarpatrien-7-one ( 5), and 1beta,13,14-trihydroxy-8,11,13-podocarpatriene-2,7-dione ( 6), were elucidated. Compounds 1, 4, 5, and 6 exhibited strong antioxidative activity.

Five new podocarpane-type trinorditerpenes were isolated from the bark of Taiwania cryptomerioides. Structures of 1beta, 14-dihydroxy-13-methoxy-6,8,11,13-podocarpatetraene (1), 1beta, 14-dihydroxy-13-methoxy-8,11,13-podocarpatriene (2), 13-hydroxy-12-methoxy-8,11,13-podocarpatrien-3-one (3), 14-hydroxy-13-methoxy-1,8,11,13-podocarpatetraen-3-one (4), and 13-methoxy-8,12-podocarpatriene-11,14-dione (5) were determined by NMR, MS, and other spectral and chemical evidence.

Further studies on the bark of Taiwania cryptomerioides found four new podocarpane derivatives, 1β,13-dihydroxy-8,11,13-podocarpatriene (1), 14,18-dihydroxy-13-methoxy-8,11,13-podocarpatriene (2), 1β,14-dihydroxy-13-methoxy-8,11,13-podocarpatriene-2,7-dione (3), and 3β,14-dihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (4), together with a known 1β,13,14-trihydroxy-8,11,13-podocarpatrien-7-one (5). Those structures were elucidated principally from spectral evidence.

Reinvestigation of the nonvolatile fraction of the acetone extractive from the heartwood of Taiwania cryptomerioides Hayata afforded taiwanin F which was established as 11-hydroxy-7-oxohinokiol on the basis of spectral data and its synthesis from hinokiol. In addition, six known compounds, taiwanin A, savinin, taiwanin C, hinokiol, taiwanin E and diphyllin were also isolated from the same fraction.

Karyotype analyses were conducted onCunninghamia konishii, Cunninghamia lanceolata, andTaiwania cryptomerioides, all members ofTaxodiaceae. The somatic chromosome number was found to be 2n = 2x = 22 in all species which concurrs with previous reports. The karyotypes are generally asymmetrical with the smaller chromosomes being more submedian than the larger ones. Chromosomes with unusual or specific structures, thought to be associated with the nucleolar organizing region, were found in each species.Cunninghamia species have a marker chromosome pair with an unusually long secondary constriction.Taiwania has an unusually long kinetochore region present in a submedian chromosome pair.

From the wood of Taiwania cryptomerioides Hayata, two new sesquiterpenes, cadinan-3β, 9β-diol and cadinan-3β, 9α-diol were isolated as minor components. Their structures were elucidated as (I) and (II), respectively.

Four crystalline components, Taiwanin A, B, C and D were isolated from the acetone extract of the heartwood of Taiwania Cryptomerioides Hayata by chromatographic method.