Analysis of leaf essential oils from the indigenous ve conifers of Taiwan

Cloning and functional characterization of three sesquiterpene synthase genes from Chamaecyparis formosensis Matsumura

Terpene synthase (TPS) analysis may contribute to a better understanding of terpenoids biosynthesis and the evolution of phylogenetic taxonomy. Chamaecyparis formosensis Matsumura is an endemic and valuable conifer of Taiwan. Its excellent wood quality, fragrance, and durability make it become the five precious conifers in Taiwan. In this study, three sesquiterpene synthase genes that belong to the TPS-d2 clade were isolated and characterized through in vitro reaction of recombinant protein and in vivo reaction of Escherichia coli heterologous expression system. The main product of Cf-GerA was germacrene A using GC/MS analysis, while the product of Cf-Aco and Cf-Gor were identified as acora-4(14),8-diene and (5R,6R,10S)-α-gorgonene by using NMR analysis. These are the first reported enzymes that biosynthesize acora-4(14),8-diene and (5 R,6 R,10 S)-α-gorgonene. Both sesquiterpene synthases may isomerize the farnesyl pyrophosphate substrate to nerolidyl pyrophosphate for further cyclization. Cf-Aco may catalyze 1,6-cyclization of nerolidyl cation while Cf-Gor may catalyze through an uncharged intermediate, isogermacrene A.

Consumer Acceptability and Sensory Profile of Three New Celery (Apium graveolens) Hybrids and Their Parental Genotypes

Celery is a stalky green vegetable that is grown and consumed globally and used in many cuisines for its distinctive taste and flavour. Previous investigations identified the aroma composition of celery and profiled its sensory characteristics using a trained panel; however, evaluation of the sensory characteristics of celery combined with a consumer panel, where consumer preferences and acceptability are determined, is novel. In this study, three parental genotypes (12, 22 and 25) and three new hybrids (12x22, 22x12 and 25x12) were presented to a trained sensory panel (n = 12) for profiling and a consumer panel (n = 118), where liking and preference were assessed. Celery samples were analysed by SPME GC–MS and significant differences in aroma composition between all samples were identified, causing significant differences in the sensory profile. Furthermore, significant differences in attributes assessed for liking (appearance, aroma, texture and overall) were identified. Consumer segmentation identified three groups of consumers exhibiting differences in the hedonic reaction to the samples. Sweet and bitter taste along with overall flavour were identified as drivers of liking. Hybrid 25x12 was found to be the hybrid that exhibited high intensities for most of the attributes assessed.

Unveiling Monoterpene Biosynthesis in Taiwania cryptomerioides via Functional Characterization

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.

Interpopulation Variability in the Essential Oil Composition of Cistus creticus subsp. eriocephalus from Sardinia

Cistus genus is widespread in the Mediterranean regions with several species and is traditionally known as a natural remedy, but few previous phytochemical researches have been reported on Cistus species growing in Sardinia. The aim of this work was to study the interpopulation variability of the volatiles of C. creticus subsp. eriocephalus to find out the natural chemotypes of this taxon for chemotaxonomic purposes. Plant material was collected from seven wild populations in Sardinia. The oils from aerial part were obtained by hydrodistillation and analyzed by GC/MS enabling to identify 185 compounds. The seven samples showed appreciable variations in their chemical composition. MA was found almost exclusively linear hydrocarbons (85%) and MN presented fatty acids (36.97%) as major fraction. CP and MN had high quantity of non-terpenic carbonylic compounds (63% and 69%, respectively) and in CP was found also sclareol, a well-known antimicrobial compound. PCA analysis showed the existence of a high interpopulation variability within the essential oils of C. creticus subsp. eriocephalus growing in Sardinia. For example, MN and CP are very close to each other as CG is close to PM. BN is isolated from the others Cistus populations due to lacking essential oil. These data suggest that the basis of variation in the volatile composition of seven C. creticus subsp. eriocephalus populations depends on hybridization and that the sample without essential oil is the only one no-hybridized.

Composition, in vitro Cytotoxicity, Anti-mildew and Anti-wood-decay Fungal Activities of the Bark Essential Oil of Cunninghamia lanceolata var. konishii from Taiwan

In this study, cytotoxicity, anti-mildew and anti-wood-decay fungal activities of the bark essential oil and its constituents from Cunninghamia lanceolata var. konishii were evaluated in vitro against three human cancer cell lines, seven mildew fungi, and four wood decay fungi, respectively. The main compounds responsible for the cytotoxicity, anti-mildew, and anti-wood decay fungal activities were also identified. The essential oil from the barks of C. lanceolata var. konishii was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS, respectively. The bark oil mainly consisted of ferruginol (15.1%), β-caryophyllene (11.2%), α-cadinol (10.9%) and cedrol (10.1%). The essential oil exhibited cytotoxic activity against human oral, liver, and lung cancer cells. The active source compounds were α-cadinol, cedrol, β-caryophyllene, and ferruginol. The bark oil was shown to have excellent anti-mildew and anti-wood-decay fungal activities, the active compounds being evaluated as α-cadinol, cedrol, and ferruginol.

Antifungal activity of lemon, eucalyptus, thyme, oregano, sage and lavender essential oils against Aspergillus niger and Aspergillus tubingensis isolated from grapes

Today, it is very important to find out the protection of products of natural origin as an alternative to synthetic fungicides. The promising alternative is the use of the essential oils (EOs). Essential oils from plants have great potential as a new source of fungicide to control the pathogenic fungi.The main objective of this study was evaluation of the antifungal activity of lemon (Citrus lemon L.), eucalyptus (Eucalyptus globulus LABILL.), thyme (Thymus vulgaris L.), oregano (Origanum vulgare L.) sage (Salvia officinalis L.) and lavender (Lavandula angustifolia MILLER.) EOs against Aspergillus niger and Aspergillus tubingensis isolated from grapes and their ability to affect the growth. It was tested by using the vapor contact with them. At first both tested isolates were identified by using PCR method. Sequence data of 18S rRNA supported the assignment of these isolates to the genus Aspergillus and species A. niger (ITS region: KT824061; RPB2: KT824060) and A. tubingensis (ITS region: KT824062; RPB2: KT824059). Second, EO antifungal activity was evaluated. The effect of the EO volatile phase was confirmed to inhibit growth of A. niger and A tubingensis. EOs were diluted in DMSO (dimethyl sulfoxide) final volume of 100 μL. Only 50 μL this solution was distributed on a round sterile filter paper (1 x 1 cm) by micropipette, and the paper was placed in the center of the lid of Petri dishes. Dishes were kept in an inverted position. The essential oils with the most significant activity were determined by method of graded concentration of oils - minimum inhibitory doses (MIDs). The most effective tested EOs were oregano and thyme oils, which totally inhibited growth of tested isolates for all days of incubation at 0.625 μL.cm-3 (in air) with MFDs 0.125 μL.cm-3 (in air). Lavender EO was less active aginst tested strains (MIDs 0.313 μL.cm-3). The results showed that the tested EOs had antifungal activity, except lemon and eucalyptus. Sage EO was the only one which decelerated the radial growth of colony of both tested strains after all days of cultivation in comparison with a control sets. Our study provides the support that essential oils can be used to control plant pathogens such as A. niger and A. tubingensis.

Chemical Composition and Anti-mildew Activities of Essential Oils from Different Parts of Michelia compressa var. formosana

In this study, anti-mildew activities of the essential oils of the leaves, wood, twigs, flowers, and their constituents from Michelia compressa var. formosana were evaluated in vitro against 7 mildew fungi. The main compounds responsible for the anti-mildew activities were isolated and identified. The essential oils from the fresh leaves, wood, twigs, and flowers of M. compressa var. formosana were isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. The essential oil yield from the flowers was the highest, and the oils obtained from the 4 parts of the tree were composed mainly of sesquiterpenoids. The leaf oil consisted primarily of α-cadinol (18.9%) and germacrene D (18.5%); the twig oil's main constituent was α-cadinol (19.1%); the wood oil's major components were α-cadinol (25.7%) and β-eudesmol (20.2%); and the flower oil contained α-cadinol (11.4%). Comparing the anti-mildew activities of the oils suggested that wood oil was the most effective. Further fractionation of the wood oil produced α-cadinol, β-eudesmol, τ-cadinol, and elemol. The 4 compounds exhibit very strong anti-mildew activities, and these in descending order are α-cadinol, elemol, β-eudesmol, and τ-cadinol. For the anti-mildew activities of the wood oil, the active source compounds were determined to be α-cadinol, elemol, β-eudesmol, and τ-cadinol.

Essential Oil from the Heartwood of Taiwan fir Ameliorates LPS-induced Inflammatory Response by Inhibiting the Activation of Mitogen-activated Protein Kinase

The essential oil from the heartwood of Taiwan fir (EOTC) was demonstrated to exhibit anti-inflammatory activity in lipopolysaccharide (LPS)-activated mouse macrophages. EOTC reduced nitrite oxide levels and inducible nitrite oxide synthase expression in, and tumor necrosis factor-α and interleukin-6 secretion by, LPS-activated macrophages without affecting cyclooxygenase-2 expression. EOTC reduced the levels of interleukin-1β precursor induced by LPS and decreased the NLRP3 inflammasome-derived interleukin-1β secretion induced by LPS and adenosine triphosphate. In addition, the phosphorylation levels of ERK1/2, JNK1/2, and p38 in LPS-activated macrophages were reduced by EOTC. Furthermore, EOTC was composed of oxygenated sesquiterpenes (68.4%), sesquiterpene hydrocarbons (28.9%) and diterpenes (0.9%). The major compounds of the oxygenated sesquiterpenes were τ-cadinol (23.9%), α-cadinol (21.1%) and cedrol (16.9%). These findings suggest that EOTC may be a candidate for the development of anti-inflammatory agents for preventing and ameliorating inflammation-related diseases.

Insecticidal activities of Cunninghamia konishii Hayata against Formosan subterranean termite, Coptotermes formosanus (Isoptera: Rhinotermitidae)

BACKGROUND

Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), is a major urban pests in many countries throughout the world. In an attempt to find natural products that could be employed in the effective and environmentally friendly control of the termite, this study investigates, for the first time, the insecticidal activities of the wood and leaf essential oils and ethanolic extracts from Cunninghamia konishii Hayata against C. formosanus according to direct contact application.

RESULTS

Wood and leaf essential oils and wood ethanolic extract showed the excellent antitermitic activities. Among the four fractions of wood ethanolic extract, the hexane-soluble fraction showed the strongest antitermitic activities. In addition, β-elemol and α-cadinol showed excellent inhibitory action against C. formosanus.

CONCLUSION

The results clearly reveal that the wood and leaf essential oils and ethanolic extract from C. konishii, and their effective constituents, served as potential, eco-friendly termite-control agents.

Chemical Composition and Anti-inflammatory Activity of Chamaecyparis obtusa f. formosana Wood Essential Oil from Taiwan

Chamaecyparis obtusa Siebold & Zucc. f. formosana Hayata (Cupressaceae) is one of the treasured conifers in Taiwan. In this study, the wood essential oil of the species was extracted and its anti-inflammatory bioactivities analyzed. The composition analysis of the essential oil yielded a total of 57 compounds with α-terpineol (19.4%), τ-muurolol (16.9%), borneol (16%), and α-cadinol (10.9%) predominating. The anti-inflammatory assays of the essential oil suggest that C. obtusa f. formosana wood oil has no cytotoxicity, and was capable of inhibiting the expressions of tumor necrosis factor (TNF-α), IL-6, IL-1, pro IL-1β, NO, iNOS, and NLRP3 in murine macrophage cells. It was unable, however, to inhibit the expression of COX-2. Further investigation of the effect of the essential oil on the cellular signal transduction indicated that it was capable of inhibiting ERK1/2, JNK1/2 and p38; it also showed excellent inhibition against ROS. Thus, the overall results indicated that C. obtusa f. formosana wood oil had very good anti-inflammatory efficacies.

Chemical and biological characterization of novel essential oils from Eremophila bignoniiflora (F. Muell) (Myoporaceae): a traditional Aboriginal Australian bush medicine

Essential oils were extracted by hydrodistillation from the traditional Australian medicinal plant Eremophila bignoniiflora, characterized chemically and then screened for bioactivity. Characterization and quantification were completed using gas chromatography-mass spectrometry (GC-MS) and GC-flame ionization detection, respectively. Antimicrobial capacity was assessed using disc diffusion and micro-titre plate broth dilution and further characterized using thin layer chromatography followed by bioautography to assign activity to separated individual active components. Antifungal capacity was investigated using micro-titre plate broth dilution against pathogenic Trichophyton species. Free radical scavenging ability was assessed using the diphenylpicrylhydradyl reaction in methanol. The predominant components of the essential oil were fenchyl-acetate and bornyl-acetate. However, bioautography indicated antimicrobial ability to be largely linked to the less abundant, more polar constituents. Oils displayed only modest antifungal ability against pathogenic Trichophyton species associated with dermatophytosis, but moderate to high antimicrobial activity, particularly against the yeast Candida albicans and the bacteria Staphylococcus epidermidis. Essential oils exhibited relatively low free radical scavenging ability. Speculation over the role of essential oils in the traditional medicinal applications of E. bignoniiflora follows, exploring correlations between traditional use and investigated bioactivities.

Composition, Anticancer, and Antimicrobial Activities in vitro of the Heartwood Essential Oil of Cunninghamia lanceolata var. konishii from Taiwan

This study investigated the chemical composition, anticancer, and antimicrobial activities in vitro of the essential oil isolated from the heartwood of Cunninghamia lanceolata var. konishii from Taiwan. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Thirty-seven compounds were identified, representing 100% of the oil. The main components identified were cedrol (58.3%), α-cedrene (11.8%), α-terpineol (4.2%) and β-cedrene (3.5%). The oil exhibited cytotoxic activity against human lung, liver and oral cancer cells. The active source compound was cedrol. The antimicrobial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against ten microbial species. The oil exhibited strong growth suppression against Gram-positive bacteria and yeast with inhibition zones of 42~50 mm to MIC values of 31.25~62.5 μg/mL, respectively. For the antimicrobial activities of the oil, the active compound was determined to be cedrol.

Composition, Antioxidant, Antimicrobial and Anti-wood-decay Fungal Activities of the Twig Essential Oil of Taiwania cryptomerioides from Taiwan

This study investigated the chemical composition, antioxidant, antimicrobial and anti-wood-decay fungal activities of the essential oil isolated from the twigs of Taiwania cryptomerioides from Taiwan. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of 35 compounds were identified, representing 100% of the oil. The main components identified were α-cadinol (45.9%), ferruginol (18.9%) and β-eudesmol (10.8%). The antioxidant activity of the oil was tested by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging capability test. The results showed an IC50 of 90.8 ± 0.2 μg/mL. The active source compound was ferruginol. The antimicrobial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against ten microbial species. The oil exhibited strong growth suppression against Gram-positive bacteria and yeast with inhibition zones of 45~52 mm and MIC values of 31.25~62.5 μg/mL, respectively. The anti-wood-decay fungal activity of the oil was also evaluated. The oil demonstrated excellent activity against four wood-decay-fungal species. For the antimicrobial and anti-wood-decay fungal activities of the oil, the active source compounds were determined to be α-cadinol, β-eudesmol and ferruginol.

Phytochemicals from Cunninghamia konishii Hayata act as antifungal agents

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.

Rapid differentiation of three Chamaecyparis species (Cupressaceae) grown in Taiwan using solid-phase microextraction-gas chromatography/mass spectrometry, cluster analysis, and principal component analysis

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.

Phylogenetic relationships of the genus Chamaecyparis inferred from leaf essential oil

The species differentiation between Chamaecyparis formosensis, C. obtusa var. formosana, and C. obtusa, based on the composition of the leaf essential oils, was studied. The characterization of the oils by GC-FID and GC/MS analyses showed remarkable differences between these three essential oils. Cluster analysis (CA) and principal-component analysis (PCA) distinguished three groups of essential oils. The C. formosensis oil was dominated by α-pinene while those isolated from C. obtusa var. formosana and C. obtusa were characterized by high levels of (-)-thujopsene and α-terpinyl acetate, respectively. Moreover, the phylogenetic relationships of the genus Chamaecyparis were in agreement with previous findings based on morphological and molecular evidence. In addition, the essential oils from C. obtusa var. formosana could be classified into three chemical types, according to their different characteristic main compounds (β-elemol, (-)-thujopsene, and cis-thujopsenal). The biochemical correlations between the major constituents of the Chamaecyparis species were examined and their relationship is discussed.

Composition and Anti-Wood-Decay Fungal Activities of the Leaf Essential oil of Machilus philippinensis from Taiwan

The hydrodistilled leaf essential oil of Machilus philippinensis was analyzed to determine its composition and yield. Seventy compounds were identified, the main ones being β-caryophyllene (13.6%), α-pinene (12.0%), α-cadinol (7.4%), cis-ocimene (7.0%), spathulenol (5.6%), (E)-nerolidol (5.3%), tau-cadinol (4.8%) and β-pinene (4.5%). Monoterpene hydrocarbons (36.1%) and oxygenated sesquiterpenes (33.0%) were the predominant groups of compounds. The leaf oil exhibited excellent anti-wood-decay fungal activities.

Composition and Antimicrobial Activity of the Leaf Essential oil of Litsea kostermansii from Taiwan

The hydrodistillated leaf essential oil of Litsea kostermansii was analyzed to determine its composition and yield. Seventy-three compounds were identified, the main components being β-eudesmol (22.5%), γ-eudesmol (18.6%), δ-selinene (8.5%), α-eudesmol (6.0%), and γ-muurolene (4.7%). Oxygenated sesquiterpenes (66.2%) and sesquiterpene hydrocarbons (32.8%) were the predominant groups of compounds. The leaf oil exhibited excellent antimicrobial activities.

Composition and Antimicrobial Activity of the Leaf Essential Oil of Litsea Nakaii from Taiwan

The leaf essential oil of Litsea nakaii was isolated by hydrodistillation and analyzed to determine its composition and yield. Fifty-five compounds were identified, the main components being α-humulene (15.5%), δ-cadinene (9.2%), ( E)-β-ocimene (8.1%), and δ-selinene (7.1%). The leaf oil exhibited excellent antimicrobial activities.