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This study aimed to develop a rapid and accurate analytical method for discriminating three Chamaecyparis species (C. formosensis, C. obtusa, and C. obtusa var. formosana) that could not be easily distinguished by volatile compounds. A total of 23 leaf samples from three species were analyzed by static-headspace (static-HS) coupled with gas chromatography-mass spectrometry (GC-MS). The static-HS procedure, whose experimental parameters were properly optimized, yielded a high Pearson correlation-based similarity between essential oil and VOC composition (r = 0.555-0.999). Thirty-six major constituents were identified; along with the results of cluster analysis (CA), a large variation in contents among the three different species was observed. Principal component analysis (PCA) methods illustrated graphically the relationships between characteristic components and tree species. It was clearly demonstrated that the static-HS-based procedure enhanced greatly the speed of precise analysis of chemical fingerprint in small sample amounts, thus providing a fast and reliable tool for the prediction of constituent characteristics in essential oil, and also offering good opportunities for studying the role of these feature compounds in chemotaxonomy or ecophysiology.

Ferruginol has antifungal activity against wood-rot fungi (basidiomycetes). However, specific research on the antifungal mechanisms of ferruginol is scarce. Two-dimensional gel electrophoresis and fluorescent image analysis were employed to evaluate the differential protein expression of wood-rot fungus Trametes versicolor treated with or without ferruginol. Results from protein identification of tryptic peptides via liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI-MS/MS) analyses revealed 17 protein assignments with differential expression. Downregulation of cytoskeleton β-tubulin 3 indicates that ferruginol has potential to be used as a microtubule-disrupting agent. Downregulation of major facilitator superfamily (MFS)–multiple drug resistance (MDR) transporter and peroxiredoxin TSA1 were observed, suggesting reduction in self-defensive capabilities of T. versicolor. In addition, the proteins involved in polypeptide sorting and DNA repair were also downregulated, while heat shock proteins and autophagy-related protein 7 were upregulated. These observations reveal that such cellular dysfunction and damage caused by ferruginol lead to growth inhibition and autophagic cell death of fungi.

There is a growing interest in the exploitation of the residues generated by plants. This study explored the potential beneficial health effects from the main biowaste, tea seed pomace, produced when tea seed is processed. DPPH radical scavenging and total phenolic content assays were performed to evaluate the in vitro activities of the extracts. Caenorhabditis elegans was used as in vivo model to evaluate the beneficial health effects, including antioxidant activity, delayed aging, and reduced amyloid-β toxicity. Among all soluble fractions obtained from the extracts of tea seed pomace from Camellia tenuifolia, the methanol (MeOH)-soluble fraction has the best in vivo antioxidant activities. The MeOH-soluble extraction was further divided into six fractions by chromatography with a Diaion HP-20 column eluted with water/MeOH, and fraction 3 showed the best in vitro and in vivo antioxidant activities. Further analysis in C. elegans showed that the MeOH extract (fraction 3) of tea seed pomace significantly decreased intracellular reactive oxygen species, prolonged C. elegans lifespan, and reduced amyloid-β (Aβ) toxicity in transgenic C. elegans expressing human Aβ. Moreover, bioactivity-guided fractionation yielded two potent constituents from fraction 3 of the MeOH extract, namely, kaempferol 3-O-(2″-glucopyranosyl)-rutinoside and kaempferol 3-O-(2″-xylopyranosyl)-rutinoside, and both compounds exhibited excellent in vivo antioxidant activity. Taken together, MeOH extracts of tea seed pomace from C. tenuifolia have multiple beneficial health effects, suggesting that biowaste might be valuable to be explored for further development as nutraceutical products. Furthermore, the reuse of agricultural byproduct tea seed pomace also fulfills the environmental perspective.

Cinnamomum osmophloeum Kaneh. is an indigenous tree species in Taiwan. The present study investigates phytochemical characteristics, antioxidant activities, and longevity of the essential oils from the leaves of the mixed-type C. osmophloeum tree. We demonstrate that the essential oils from leaves of mixed-type C. osmophloeum exerted in vivo antioxidant activities on Caenorhabditis elegans. In addition, minor (alloaromadendrene, 5.0%) but not major chemical components from the leaves of mixed-type C. osmophloeum have a key role against juglone-induced oxidative stress in C. elegans. Additionally, alloaromadendrene not only acts protective against oxidative stress but also prolongs the lifespan of C. elegans. Moreover, mechanistic studies show that DAF-16 is required for alloaromadendrene-mediated oxidative stress resistance and longevity in C. elegans. The results in the present study indicate that the leaves of mixed-type C. osmophloeum and essential oil alloaromadendrene have the potential for use as a source for antioxidants or treatments to delay aging.

The antioxidant activity and delayed aging effects of hot water extracts from leaves of Chamaecyparis obtusa var. formosana were investigated. Free radical, superoxide radical scavenging, and total phenolic content assays were employed to evaluate the in vitro activities of the extracts. In addition, in vivo assays using the nematode Caenorhabditis elegans were also performed in this study. The results showed that among all soluble fractions obtained from the extracts, the ethyl acetate-soluble fraction has the best in vitro and in vivo antioxidant activities. Moreover, it decreased significantly the deposition of lipofuscin (aging pigment) and extended the lifespan of C. elegans. Bioactivity-guided fractionation yielded six potent antioxidant constituents from the ethyl acetate-soluble fraction, namely, catechin, quercetin, quercetin-3-O-α-rhamnoyranoside, myricetin-3-O-α-rhamnoyranoside, vanillic acid, and 4-hydroxybenzoic acid. Quercetin-3-O-α-rhamnoyranoside pretreatment showed the highest survival of C. elegans upon juglone exposure. Taken together, the results revealed that hot water extracts from C. obtusa var. formosana leaves have the potential to be used as a source for antioxidant or delayed aging health food.

The essential oils from leaves of Taiwan's indigenous cinnamon (Cinnamomum osmophloeum ct. cinnamaldehyde) have similar constituents as compared to that from commercial bark cinnamons. This indigenous cinnamon has been proven to have excellent bioactivities. To understand whether this indigenous cinnamon contains a high level of the hepatotoxic compound, coumarin, as often seen in Cassia cinnamons, current research focused on determining the coumarin content in this indigenous cinnamon and screening the low-coumarin clones. The results demonstrated that the coumarin contents in all tested indigenous cinnamon clones were much lower than that found in Cassia cinnamons. In addition, this indigenous cinnamon contains about 80% (w/w) of cinnamaldehyde and 0.4-2.7% (w/w) of eugenol in its leaf essential oils. This combination could provide this indigenous cinnamon a better shelf life compared to that of regular commercial cinnamons. These results suggested that leaves of this indigenous cinnamon could be a potential resource for a safer cinnamon substitute.

Barringtonia racemosa is a nocturnal flowering plant. Information on its floral volatiles and the dynamic emission profiles was very limited. In this study, the floral volatiles of B. racemosa were monitored hourly during its florescence via detached and in situ collection for the first time. The dynamic odor activity value (OAV) was calculated to elucidate the active aroma components of floral scent. Results of compositional analyses showed that the predominant floral volatiles were linalool and phenylacetaldehyde. Their emission started around 8:00 p.m., and the peak emissions were 20541 and 18234 ng h(-1) flower(-1), respectively, during 10:00 p.m.-2:00 a.m. Results from dynamic OAV profiling revealed that linalool (409 min(-1)) and phenylacetaldehyde (547 min(-1)) had higher OAVs than other components (<10 min(-1)), indicating that linalool and phenylacetaldehyde contributed mainly to the floral scent with a strong, sweet, and pleasant aroma.

The thermal stability of leaf essential oils from various Cinnamomum osmophloeum and their constituents was investigated for the first time. The results indicated that trans-cinnamaldehyde (Cin) content in eugenol-free essential oil from C. osmophloeum was affected by high temperatures. The retention of Cin (RC) decreased to 17.4% after the essential oil was incubated for 8 h at 100 °C. In contrast, essential oils containing eugenol showed greater thermal stability. Seven kinds of antioxidants were added to Cin to improve its thermal stability. Among them, eugenol endowed Cin with the best thermal stability. We also investigated the influence of various amounts of eugenol on the thermal stability of both essential oil and Cin. Both essential oil and Cin showed excellent thermal stability when 0.62 and 2.60% (v/v) eugenol were added. In short, the thermal stability of essential oil and Cin could be effectively improved by adding appropriate amounts of eugenol.

Cinnamomum osmophloeum ct. linalool is one of the chemotypes of the indigenous cinnamon in Taiwan. In this study, hydrodistillation was used for extracting the essential oils (EOs) of C. osmophloeum ct. linalool leaves collected from various plants and seasons, and GC-MS and GC-FID were used to examine variations and contents of the chemical composition in EOs. Moreover, the absolute configuration of the main constituent and its EO content were illustrated by GC-FID with a chiral column. In addition, we also investigated the effect of the extraction time (1, 2, 6, and 10 h) on the yield of EO and the contents of the main constituents. Results from this study revealed that the average EO yield of 12 plants was 3.7%, and linalool accounted for more than 90%. The linalool in the EO was proved to be pure S-(+)-linalool, and its content in the leaves ranged from 28.8 ± 0.3 to 35.1 ± 0.2 mg/g. Furthermore, there were no obvious differences in EO yield and S-(+)-linalool content from various plants and seasons. On the other hand, we also demonstrated that EO and S-(+)-linalool from C. osmophloeum ct. linalool leaves can be completely extracted out by 1 h of hydrodistillation.

Cinnamomum osmophloeum Kaneh is an indigenous tree species in Taiwan. In this study, phytochemical characteristics and antioxidant activities of the essential oils and key constituents from the leaves of two C. osmophloeum clones were investigated. The two trees possess two chemotypes, which were classified as the cinnamaldehyde type and camphor type. We demonstrated that the essential oils from C. osmophloeum leaves exerted in vivo antioxidant activities in Caenorhabditis elegans. In addition, trans-cinnamaldehyde and D-(+)-camphor, which respectively represent the major compounds in the cinnamaldehyde-type and camphor-type trees, exerted significant in vivo antioxidant activities against juglone-induced oxidative stress in C. elegans. Moreover, expressions of antioxidative-related genes, including superoxide dismutase (SOD) and glutathione S-transferase (GST), were significantly induced by trans-cinnamaldehyde and D-(+)-camphor from C. osmophloeum leaves. Our results showed that the essential oils from C. osmophloeum leaves and their major compounds might have good potential for further development as nutraceuticals or antioxidant remedies.

The aims of the present study were to isolate and identify the antifungal compounds from the ethanolic extract of Cunninghamia konishii wood and to evaluate their antifungal activities against wood decay fungi. The results showed that the n-Hex soluble fraction of the ethanolic extract from C. konishii wood had an excellent inhibitory effect against Lenzites betulina, Trametes versicolor, Laetiporus sulphureus, and Gloeophyllum trabeum, with IC(50) values of 33, 46, 62, and 49 μg/mL, respectively. By following the bioactivity-guided fractionation procedure, four sesquiterpenes, T-cadinol, cedrol, T-muurolol, and (-)-epi-cedrol, and three diterpenes, 13-epi-manool, cis-abienol, and isoabienol, were identified from the active subfractions. Among the main constituents of the ethanolic extract from C. konishii, T-cadinol, cedrol, and T-muurolol efficiently inhibited the growth of four wood-rot fungi at the concentration of 100 μg/mL, with antifungal indices of 51.4-100.0%, 68.3-100.0%, and 39.5-100.0%, respectively. Results of this study show that the ethanolic extract of C. konishii wood may be considered as a potent source of T-cadinol, cedrol, and T-muurolol as new natural antifungal agents.

Three Chamaecyparis species (C. formosensis, C. obtusa, and C. obtusa var. formosana) are difficult to distinguish by the naked eye. Therefore, from the chemotaxonomic point of view, it would be valuable to find a simple and rapid method to differentiate these three Chamaecyparis species. In this study, the chemical compositions of biogenic volatile organic compounds (BVOCs) from mature leaves were analyzed using solid-phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS). Then cluster analysis (CA) and principal component analysis (PCA) were conducted for the BVOC constituents to reveal the differences among these three species. Results from SPME-GC/MS showed that the compositions of BVOCs from the three species were distinctly different. Moreover, these species were clearly differentiated according to the results of CA and PCA. In conclusion, the findings of this study suggest that SPME-GC/MS coupled with CA and PCA is a feasible and rapid technique to differentiate Chamaecyparis species with similar morphological characteristics.

An insecticidal toxin gene, tccC, was cloned from the recently discovered novel species Pseudomonas taiwanensis using degenerate PCR and genomic walking. The DNA sequence of the tccC gene (2,940 bp) has an open reading frame encoding 980 amino acids with a calculated molecular weight of 107.93 kDa. The amino acid sequence alignment showed the highest sequence identity (41.2%) with the insecticidal toxin from Pseudomonas entomophila. To examine the insecticidal functionality of the tccC gene product, TccC was heterologously expressed in Escherichia coli as a recombinant His6 fusion protein and purified by immobilized metal ion-affinity chromatography. The recombinant TccC was fed to Drosophila larvae at a concentration of 350 ppm, which induced about 60% mortality within 72 h. The recombinant TccC was stable at pH 7.0 and at 37 °C. When the pH was less than 5.0 or greater than 9.0, or temperature was greater than 55 °C, less than 20% Drosophila larvae mortality was observed. These results prove that Pseudomonas taiwanensis could be used as a source for developing novel biopesticides.

In this study, the antihyperuricemic effect of Acacia confusa heartwood extracts and their phytochemicals on potassium oxonate (PO)-induced acute hyperuricemia was investigated for the first time. All treatments at the same dosage (100 mmol/kg) were administered to the abdominal cavity of PO-induced hyperuricemic mice, and serum uric acid level was measured at 3 h after administration. In experimental mice, serum uric acid level was significantly suppressed by the administration of A. confusa heartwood extracts and their major phytochemicals, (-)-2,3-cis-3,4-cis-3,3',4,4',7,8-hexahydroxyflavan, (-)-2,3-cis-3,4-cis-4'-methoxy-3,3',4,7,8-pentahydroxyflavan, melanoxetin, transilitin, and okanin, relative to the PO group. The direct inhibitory effect of these five compounds on xanthine oxidase (XOD) activity was examined using isothermal titration calorimetry (ITC). Among them, melanoxetin showed a more remarkable inhibitory effect on XOD activity than allopurinol, a clinical drug used for XOD inhibitor. To further understand the stereochemistry between XOD and melanoxetin (or allopurinol), structure-based molecular modeling was performed. Melanoxetin undergoes extended interactions in the hydrophobic region via the 3',4'-dihydroxyphenyl moiety, thus accounting for its higher binding affinity to XOD than allopurinol. These results indicate that A. confusa heartwood extracts and their major phytochemicals exhibit strong XOD inhibitory effects, which reduce serum uric acid levels while inhibiting uric acid generation in purine metabolism.

The fungus Taiwanofungus camphoratus is commonly used for medicinal purposes in Taiwan. It is used as a detoxicant for food poisoning and considered to be a precious folk medicine for hepatoprotection and anti-inflammation. In this study, a lipopolysaccaride (LPS)-challenged ICR mouse acute inflammation model and a LPS-induced macrophage model were used to evaluate the anti-inflammatory activity of T. camphoratus. Ethanol extract of T. camphoratus significantly inhibited expression of iNOS and COX-2 in the liver of LPS-challenged acute inflammatory mice. The ethyl acetate fraction and its isolated compound, antrocamphin A, significantly suppressed nitrite/nitrate concentration in LPS-challenged RAW 264.7 cells. Antrocamphin A showed potent anti-inflammatory activity by suppressing pro-inflammatory molecule release via the down-regulation of iNOS and COX-2 expression through the NF-kappaB pathway. This study, therefore, first demonstrates the bioactive compound of T. camphoratus and illustrates the mechanism by which it confers its anti-inflammatory activity.

This study investigates bioactivities and active phytochemicals of the extracts of twigs and branches from the indigenous Taiwanese tree Acacia confusa Merr. The bioassay-guided fractionation yielded 8 potent antioxidative phytochemicals. Catechins are the major components in the extract of 5 cm branch bark, including catechin, catechin-3-O-rhamnopyranoside, epi-catechin, and quercetin-3-O-rhamnopyranoside, while flavonol glycosides are the major components in twig extract, namely, myricetin-3-O-glucopyranoside, myricetin-3-O-rhamnopyranoside, quercetin-3-O-rhamnopyranoside, myricetin-3-O-(2''-O-galloyl)-alpha-rhamnopyranoside, and luteolin. Of the test compounds, myricetin-3-O-(2''-O-galloyl)-alpha-rhamnopyranoside exhibited the highest antioxidant activity against DPPH radicals, showing a 2.8-fold lower IC(50) value of 5.3 microM related to that of quercetin. On the other hand, catechins apparently had no XOD inhibitory effect apart from their good antioxidant activities, while luteolin exhibited excellent activity against XOD with an IC(50) value of 11.6 microM. These results may provide useful information for future studies on the applications of A. confusa to be used as a source for natural health products.

Acacia confusa Merr. (Leguminosae) is traditionally used as a medicinal plant in Taiwan. In the present study, the XOD-inhibitory activity of ethanolic extracts from A. confusa was investigated for the first time. Results demonstrated that the ethanolic extract of A. confusa heartwood had a strong XOD-inhibitory activity. Among all fractions derived from heartwood extracts, the EtOAc fraction exhibited the best inhibitory activity. Following column chromatography and reverse-phase high-performance liquid chromatography, eight specific phytochemicals including melanoxetin, 7,8,3',4'-tetrahydroxyflavone, transilitin, okanin, 3,7,8,3'-tetrahydroxy-4'-methoxyflavone, 7,8,3'-trihydroxy-3,4'-dimethoxyflavone, 7,3',4'-trihydroxyflavone, and 7,3',4'-trihydroxy-3-methoxyflavone were isolated and identified from the EtOAc fraction. In addition, the IC(50) values indicated that okanin showed the strongest XOD-inhibitory effect (IC(50) value of 0.076 microM), followed by melanoxetin (0.274 microM) and allopurinol (4.784 microM). The present study revealed that okanin and melanoxetin showed excellent inhibition on XOD in noncompetitive and competitive mode, respectively, and their inhibitory activity is better than that of allopurinol. This is the first study that demonstrates the XOD-inhibitory performance of okanin and melanoxetin.

The purpose of this study was to investigate the repellent activities of essential oils from Cryptomeria japonica (sugi) against adults of mosquitoes Aedes aegypti and Aedes albopictus . Comparison of essential oils from four different plant parts of C. japonica revealed that essential oil from its leaf exhibited the best repellent activity against mosquitoes. To understand the relationship between volatile organic compounds and repellent activity, the solid-phase microextraction (SPME) method was employed to analyze volatile organic compounds of leaf essential oil. The SPME fiber was coated with divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS). The major volatile organic compounds in the cage were 3-carene, alpha-terpinene, limonene, gamma-terpinene, and terpinolene at 0 min. Results demonstrated that (-)-terpinen-4-ol was the major volatile organic compound adsorbed by SPME fiber during repellent assays. Furthermore, the repellent activities of six compounds against adults of the mosquitoes were evaluated, and the results revealed that (-)-terpinen-4-ol exhibited the best repellent activity against A. aegypti and A. albopictus.

Acacia confusa Merr. (Leguminosae) is traditionally used as a medicinal plant in Taiwan. In the present study, anti-inflammatory activity of extracts from the heartwood of A. confusa were investigated for the first time. Results demonstrated that ethanolic extracts of A. confusa heartwood strongly suppressed NO production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. Among all fractions derived from ethanolic extracts, the EtOAc fraction exhibited the best inhibitory activity. Following column chromatography and reverse-phase high-performance liquid chromatography, 13 specific phytocompounds including 5 new flavonoids (i.e., 7,8,3',4'-tetrahydroxy-4-methoxyflavan-3-ol, 7,8,3',4'-tetrahydroxyflavone, 7,8,3'-trihydroxy-3,4'-dimethoxyflavone, 7,3',4'-trihydroxyflavone, and 7,3',4'-trihydroxy-3-methoxyflavone) were isolated and identified from the EtOAc fraction. In addition, melanoxetin (3,7,8,3',4'-pentahydroxyflavone), a major compound in the EtOAc fraction, markedly suppressed LPS-induced NO and prostaglandin E 2 (PGE 2) production. Moreover, melanoxetin completely suppressed gene expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) at 50 and 100 microM, respectively. This is the first report to identify the inhibitory bioactivities of melanoxetin on iNOS and COX-2.

Acacia confusa is traditionally used as a medicinal plant in Taiwan. In this study, phytochemicals and antioxidant activities of extracts from flowers of A. confusa were investigated for the first time. In addition, a rapid screening method, online RP-HPLC-DPPH system, for individual antioxidants in complex matrices was developed. Accordingly, six antioxidants including gallic acid ( 1), myricetin 3-rhamnoside ( 2), quercetin 3-rhamnoside ( 3), kaempferol 3-rhamnoside ( 4), europetin 3-rhamnoside ( 5), and rhamnetin 3-rhamnoside ( 6) were detected using the developed screening method. Of these, compounds 2, 3, and 5 were found to be major bioactive phytochemicals, and their contents were determined as 11.3, 6.7, and 8.7 mg/g of crude extract, respectively. By comparison with quercetin, a well-known antioxidant, these compounds had the order of compound 2 > compound 5 > quercetin > compound 3 for DPPH radical-scavenging activity. Their IC 50 values were 3.0, 3.2, 4.5, and 7.4 microM, respectively. Moreover, the same order was observed for superoxide radical-scavenging activity, and their IC50 values were 2.6, 2.7, 4.3, and 5.3 microM, respectively. However, for lipid peroxidation, quercetin, an aglycon, showed the best inhibitory activity. The IC50 values of quercetin, compound 2, compound 5, and compound 3 were 46.7, 88.5, 90.7, and 124.6 microM, respectively. These results indicated that a rhamnoside at the C3 position of flavonoids had a negative effect on radical-scavenging activity and antilipid peroxidation. In contrast, the number of hydroxyl groups on the B-ring exhibited a positive relationship with their inhibitory activities.

The leaf essential oil from indigenous cinnamon (Cinnamomum osmophloeum Kaneh.) was investigated by gas chromatography-mass spectrometry, and 21 compounds were identified. The major constituents of leaf essential oil were the monoterpenes 1,8-cineole (17.0%) and santolina triene (14.2%) and the sesquiterpenes spathulenol (15.7%) and caryophyllene oxide (11.2%). In the antiinflammatory activity assay, we demonstrated that the essential oil has a higher capacity to inhibit proIL-1beta protein expression induced by LPS-treated J774A.1 murine macrophage. At dosages of 60 microg/mL, essential oil clearly inhibited proIL-1beta protein expression. Furthermore, a dose of 60 microg/mL of essential oil was effectively inhibitory for IL-1beta and IL-6 production but not for TNF-alpha, suggesting that essential oil was bioactive in antiinflammation in vitro. This study is the first to report antiinflammatory activity of extracts obtained from the leaf essential oil of C. osmophloeum.

In the present study, the ethanolic extracts from the heartwood of Acacia confusa, a species indigenous to Taiwan, exhibit strong antioxidant effects. Among all the fractions from ethanolic extracts of heartwood, the EtOAc soluble fraction exhibits the best antioxidant activity. The 80% 1,1-diphenyl-2-picrylhydrazyl radical inhibitory activity by the EtOAc extract was observed at a concentration of 5 mug/mL, and at the same dosage there was a similar free radical scavenging activity for (-)-ascorbic acid and (+)-catechin, both of which are well-known antioxidants. In addition, the EtOAc extract also protects PhiX174 supercoiled DNA against strand scission induced by hydroxyl radical. Furthermore, following by column chromatography and reverse-phase high-performance liquid chromatorgrapy, 10 pure phenolic compounds, including three major antioxidants (3,7,8,3',4'-pentahydroxyflavone, 7,8,3',4'-tetrahydroxy-3-methoxyflavone, and 3,4,2',3',4'-pentahydroxy-trans-chalcone) and a new flavonoid (3,7,8,3'-tetrahydroxy-4'-methoxyflavone), were isolated from the ethanolic extracts of A. confusa heartwood.

In this study antifungal activities of essential oils from different tissues of Japanese cedar (Cryptomeria japonica D. Don) against four wood decay fungi and six tree pathogenic fungi were investigated. In addition, the yields of essential oils obtained by water distillation were compared and their constituents determined by GC-MS analyses. The yield of essential oils from four tissues of Japanese cedar is in the decreasing order of leaf (27.38 mL/kg) > bark (6.31 mL/kg) > heartwood (3.80 mL/kg) > sapwood (1.27 mL/kg). Results obtained from the antifungal tests demonstrate that the essential oil of Japanese cedar heartwood used against Laetiporus sulphureus and Trametes versicolor and sapwood essential oil used against L. sulphureus had strong antifungal activities at 500 mug/mL, with IC(50) values of 39, 91, and 94 microg/mL, respectively. Besides, the essential oils of Japanese cedar heartwood used against Rhizoctonia solani, Collectotrichum gloeosporioides, Fusarium solani, and Ganoderma australe had strong antifungal activities at 500 microg/mL, with IC(50) values of 65, 80, 80, and 110 microg/mL, respectively. GC-MS analyses showed that the sesquiterpene hydrocarbon compounds dominate in the essential oil from Japanese cedar heartwood, amounting to a total percentage of 82.56%, with the major compounds of delta-cadinene (18.60%), isoledene (12.41%), and gamma-muurolene (11.82%). It is proposed that the excellent antifungal activities of Japanese cedar heartwood essential oils might correlate with the presence of these compounds.

Chemical compositions of leaf essential oils from eight provenances of indigenous cinnamon (Cinnamomum osmophloeum Kaneh.) were compared. According to GC-MS and cluster analyses, the leaf essential oils of the eight provenances and their relative contents were classified into five chemotypes-cinnamaldehyde type, linalool type, camphor type, cinnamaldehyde/cinnamyl acetate type, and mixed type. The larvicidal activities of leaf essential oils and their constituents from the five chemotypes of indigenous cinnamon trees were evaluated by mosquito larvicidal assay. Results of larvicidal tests demonstrated that the leaf essential oils of cinnamaldehyde type and cinnamaldehyde/cinnamyl acetate type had an excellent inhibitory effect against the fourth-instar larvae of Aedes aegypti. The LC(50) values for cinnamaldehyde type and cinnamaldehyde/cinnamyl acetate type against A. aegypti larvae in 24 h were 36 ppm (LC(90) = 79 ppm) and 44 ppm (LC(90) = 85 ppm), respectively. Results of the 24-h mosquito larvicidal assays also showed that the effective constituents in leaf essential oils were cinnamaldehyde, eugenol, anethole, and cinnamyl acetate and that the LC(50) values of these constituents against A. aegypti larvae were <50 ppm. Cinnamaldehyde had the best mosquito larvicidal activity, with an LC(50) of 29 ppm (LC(90) = 48 ppm) against A. aegypti. Comparisons of mosquito larvicidal activity of cinnamaldehyde congeners revealed that cinnamaldehyde exhibited the strongest mosquito larvicidal activity.

The antitermitic activities of the essential oils from the leaves of two Cinnamomum osmophloeumclones (A and B) and their chemical ingredients against Coptotermes formosanus Shiraki were investigated according to direct contact application. Results from this experiment have demonstrated that the indigenous cinnamon B leaf essential oil has a more effective antitermitic activity than indigenous cinnamon A leaf essential oil. Furthermore, when cinnamaldehyde, eugenol, and alpha-terpineol are extracted from indigenous cinnamon leaf essential oil and used at the strength of 1 mg/g, their antitermitic effectiveness is much higher than that using indigenous cinnamon leaf essential oil. Among the congeners of cinnamaldehyde examined, cinnamaldehyde has exhibited the strongest termiticidal property.

The antioxidant activity of extracts from bark and heartwood of Acacia confusa was evaluated by various antioxidant assays, including free radical and superoxide radical scavenging assays and lipid peroxidation assay as well as hydroxyl radical-induced DNA strand scission assay. In addition, an ex vivo antioxidant assay using a flow cytometric technique was also employed in this study. The results indicate that both bark and heartwood extracts clearly have strong antioxidant effects. Similar inhibitory activities for each test sample were found for both 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical generation and lipid peroxidation. As for the superoxide radical scavenging activity, the heartwood extract was more effective than the bark extract. Furthermore, the heartwood extract protected PhiX174 supercoiled DNA against strand scission induced by ultraviolet photolysis of H2O2, and it reduced the amounts of intracellular hydrogen peroxide, a reactive oxygen species, when it was co-incubated with human promyelocytic leukemia (HL-60) cells under oxidative stress.

A novel single-chained ribosome-inactivating protein (RIP) with a molecular weight of approximately 29 000 was purified from fruiting bodies of the edible mushroom Volvariellavolvacea with a procedure involving ammonium sulfate precipitation, ion-exchange chromatography on DEAE-cellulose, and gel filtration on Superdex 75. The mushroom RIP, designated volvarin, exhibited a potent inhibitory action on protein synthesis in the rabbit reticulocyte lysate system with an IC(50) value of 0.5 nM. Like most plant RIPs, volvarin acted as an N-glycosidase that depurinated rRNA from rabbit reticulocyte lysate, releasing a characteristic RNA fragment after treatment with aniline. It also exerted a deoxyribonuclease activity on supercoiled SV-40 DNA and demonstrated a strong abortifacient effect in mice.