Composition and antimicrobial activity of the leaf and twig oils of Litsea mushaensis and L. linii from Taiwan

The hydrodistilled essential oils of the leaves and twigs of Litsea mushaensis and L. linii were analyzed. Sixty-nine and ninety compounds were identified in the leaf and twig oils, respectively, of L. mushaensis. The main components of the leaf oil were beta-eudesmol (24.2%), tau-cadinol (10.2%), alpha-humulene (10.1%), alpha-pinene (9.7%), and trans-beta-ocimene (6.5%), whereas the main components of the twig oil were trans-beta-ocimene (19.5%), alpha-pinene (12.8%) and cis-beta-ocimene (7.7%). With L. linii, 72 and 78 compounds were respectively identified in the leaf and twig oils. The main components of the leaf oil were beta-selinene (15.7%), alpha-selinene (15.5%), beta-caryophyllene (12.2%), alpha-humulene (7.2%), and delta-cadinene (5.6%), and of the twig oil trans-beta-ocimene (20.8%), beta-selinene (11.4%), alpha-cadinol (6.0%), delta-cadinene (5.8%), tau-cadinol (5.4%) and beta-eudesmol (5.2%). L. mushaensis leaf oil was shown to have excellent antimicrobial and anti-wood-decay fungal activity, superior to the other oils.     

Composition, antioxidant and antimicrobial activities of leaf and twig essential oils of Litsea akoensis from Taiwan

This study analyzed the hydrodistilled essential oils in the leaves and twigs of Litsea akoensis to determine composition and yield. Seventy-one and 40 compounds were identified in the leaf and twig oils, respectively. The main components of leaf oil were limonene (18.5%), thymol (10.1%), p-cymene (9.6%), beta-caryophyllene (8.9%), and carvacrol (8.2%). The main components of twig oil were beta-phellandrene (43.7%) and trans-beta-ocimene (10.4%). The results demonstrated that leaf oil had excellent antioxidant and antimicrobial activities, superior to those of twig oil.     

Composition and antifungal activities of the leaf essential oil of Litsea coreana from Taiwan

The hydrodistilled leaf essential oil of Litsea coreana was analyzed by GC/FID and GC/MS. Fifty-two compounds were identified, the main components being n-decanal (27.5%), 2E,6E-farnesol (25.8%), beta-eudesmol (10.3%), ethyl n-dodecanoate (8.0%) and tau-cadinol (6.6%). Oxygenated sesquiterpenes (56.8%) and non-terpenoids (37.0%) were the predominant groups of compounds. The leaf oil exhibited excellent antifungal and anti-wood-decay fungal activities.     

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 alpha-cadinol (45.9%), ferruginol (18.9%) and beta-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 microg/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 microg/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 alpha-cadinol, beta-eudesmol and ferruginol.     

Composition and antifungal activities of the leaf essential oil of Neolitsea parvigemma from Taiwan

The hydrodistillated leaf essential oil of Neolitsea parvigemma was analyzed to determine its composition and yield. Sixty-two compounds were identified, the main components being beta-caryophyllene (14.2%), beta-eudesmol (12.9%), alpha-cadinol (10.2%) and tau-cadinol (8.8%). Oxygenated sesquiterpenes (48.9%) and sesquiterpene hydrocarbons (48.8%) were the predominant groups of compounds. The antifungal indexes of the leaf oil against the 7 fungi, Aspergillus clavatus, A. niger, Chaetomium globosum, Cladosporium cladosporioides, Myrothecium verrucaria, Penicillium citrinum and Trichoderma viride, were 100.0, 72.3, 100.0, 100.0, 100.0, 75.8 and 88.6% at a 1 mg/mL concentration, respectively. The oil also exhibited anti-wood-decay-fungi activity against Trametes versicolor, Phaneochaete chrysosporium, Phaeolus schweintizii, and Lenzites sulphureu with MIC values of 50, 50, 25 and 25 microg/mL, respectively. For the antifungal and anti-wood-decay fungal activities of the oil, the active source compounds were determined to be alpha-cadinol, beta-eudesmol and tau-cadinol.     

Composition and antimicrobial activities of the leaf essential oil of Machilus kusanoi from Taiwan

The hydrodistillated leaf essential oil of Machilus kusanoi was analyzed to determine its composition and yield. Twenty-three compounds were identified, the main components being beta-caryophyllene (23.3%), beta-eudesmol (17.1%), alpha-terpineol (16.0%), n-dodecanal (14.2%), and n-decanal (10.4%). Sesquiterpene hydrocarbons (28.1%) and non-terpenoids (25.0%) were the predominant groups of compounds. The leaf oil exhibited excellent antimicrobial and anti-wood-decay fungal activities.     

Composition and antipathogenic activities of the twig essential oil of Chamaecyparis formosensis from Taiwan

In this study, antipathogenic activities of the twig essential oil and its constituents from Chamaecyparis formosensis Matsum were evaluated in vitro against six plant pathogenic fungi. The essential oil from the fresh twigs was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Twenty-five compounds were identified, representing 98.9% of the oil. The main components were beta-eudesmol (25.1%), tau-muurolol (21.6%), elemol (15.0%), totarol (14.9%), and alpha-cadinol (12.4%). The twig oil (500 mcirog/mL) showed growth inhibitory activity against the phytopathogenic fungi, Fusarium oxysporum, Pestalotiopsis funereal, and Ganoderma austral, with antifungal indices of 92.7%, 71.1%, and 87.7%, respectively. In addition, the oil suppressed totally the growth of Rhizoctonia solani, Colletotrichum gloeosporioides, and Fusarium solani. In order to ascertain the source compounds of these antipathogenic activities, the main components were individually evaluated. Tau-Muurolol and alpha-cadinol exhibited excellent activity against F. oxysporum, R. solani, C. gloeosporioides, and F. solani, with IC50 < 50 microg/mL. These compounds also efficiently inhibited the mycelial growths of P. funereal and G. austral. Thus, alpha-cadinol and tau-muurolol could be considered as potential natural fungicides for controlling fungal pathogens and worth.     

Composition, antioxidant and antimicrobial activities of the seed essential oil of Calocedrus formosana from Taiwan

The hydrodistillated seed essential oil of Calocedrus formosana was analyzed to determine its composition and yield. Twenty-seven compounds were identified, the main ones being alpha-pinene (63.8%), totarol (9.9%) and ferruginol (8.9%). Monoterpene hydrocarbons (73.5%) and oxygenated diterpenes (18.8%) were the predominant groups of compounds. The seed essential oil exhibited excellent antioxidant, antimicrobial and anti-wood-decay fungal activities.     

GC/MS analysis and antimicrobial activity of the essential oil of fresh leaves of Eucalytus globulus, and leaves and stems of Smyrnium olusatrum from Constantine (Algeria)

The essential oils of fresh leaves of Eucalyptus globulus L. (Myrtaceae), and leaves and stems of Smyrnium olusatrum L. (Apiaceae), obtained by hydrodistillation in a Clevenger-type apparatus, were analyzed by GC/MS. Twenty compounds were characterized, representing 98.3% of the essential oil of E. globulus, with 1,8-cineole (48.6%), globulol (10.9%), trans-pinocarveol (10.7%), and alpha-terpineol (6.6%) as main components, while thirty-three compounds were characterized, representing 94.3% of the essential oil of S. olusatrum, with sabinene (27.1%), curzerene (13.7%), methyl-1-benzyl-2-oxocyclooctane carboxylate (12.3%), alpha-pinene (7.2%), cryptone (7.1%) and beta-pinene (5.7%) as the major components. The essential oils of E. globulus and S. olusatrum were tested against a wide range of fungal and bacterial strains. Both oils showed significant antimicrobial activity.     

Chemical composition and antimicrobial activity of the essential oils of Onychopetalum amazonicum R.E.Fr.

The essential oils from leaves, twigs and trunk bark of Onychopetalum amazonicum R.E. Fr. (Annonaceae), obtained by hydrodistillation, were analysed by GC and GC–MS, and also were evaluated for in vitro antimicrobial activity. Forty-one compounds, which correspond to 75.0–92.2% of the oil components, were identified. Major compounds were sesquiterpenes, including (E)-caryophyllene, caryophyllene oxide, spathulenol, α-gurjunene, allo-aromadendrene and α-epi-cadinol. The oils were evaluated for antimicrobial activities against four bacteria strains and five pathogenic fungi. The oil of the trunk bark exhibited good activity against Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 10538 and Kocuria rhizophila ATCC 9341, with a minimal inhibitory concentration of 62.5 μg/mL. The essential oil composition and the antimicrobial evaluation are reported for the first time for the genus Onychopetalum.     

Chemical composition and antimicrobial evaluation of the essential oils of Bocageopsis pleiosperma Maas

Essential oils from the leaves, twigs and barks of Bocageopsis pleiosperma Maas were obtained by using hydrodistillation and analysed by using gas chromatography coupled to mass spectrometry. Several compounds (51) were detected and identified, being β-bisabolene the main component in all aerial parts of the plant, with higher concentration in the leaves (55.77%), followed by barks (38.53%) and twigs (34.37%). In order to increase the biological knowledge about the essential oil of Bocageopsis species, antimicrobial activities were evaluated against the microorganisms Escherichia coli, Staphylococcus epidermidis, Enterobacter aerogenes, Candida tropicalis, Candida dubliniensis, Candida glabrata and Candida albicans. The essential oil obtained from the barks exhibited a moderate effect against S. epidermidis ATCC 1228 (MIC = 250 μg/mL), while the other oils did not exhibit antimicrobial activity. These results represent the first report about the chemical composition of B. pleiosperma and the first antimicrobial evaluation with a Bocageopsis species.     

Composition, antioxidant and antimicrobial activities of the leaf essential oil of Machilus japonica from Taiwan

The chemical composition, and antioxidant and antimicrobial activities of the essential oil isolated from the leaf of Machilus japonica from Taiwan have been investigated. The essential oil from the fresh leaves was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of 97 compounds were identified, representing 100% of the oil. The main components identified were alpha-phellandrene (14.5%), alpha-pinene (12.8%), thymol (12.6%), beta-pinene (8.3%), alpha-terpineol (6.5%) and carvacrol (6.0%). The antioxidant activity of the oil was tested by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging capability test. The results showed that the IC50 was 51.8 microg/mL. 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 48-54 mm and MIC values of 16.12-32.25 microg/mL, respectively. For the antioxidant and antimicrobial activities of the oil, the active source compounds were determined to be thymol and carvacrol.     

Chemical constituents and larvicidal activity of Hymenaea courbaril fruit peel

The chemical compositions of the essential oils from the peel of ripe and unripe fruits of Hymenaea courbaril L., obtained by hydrodistillation, were analyzed by GC and GC-MS. The main constituents of the essential oil from the peel of the ripe fruits were the sesquiterpenes alpha-copaene (11.1%), spathulenol (10.1%) and beta-selinene (8.2%), while germacrene-D (31.9%), beta-caryophyllene (27.1%) and bicyclogermacrene (6.5%) were the major compounds in the oil from unripe fruits. The essential oils were tested against Aedes aegypti larvae and showed LC50 values of 14.8 +/- 0.4 microg/mL and 28.4 +/- 0.3 microg/mL for the ripe and unripe fruit peel oils, respectively. From the peel of the ripe fruits, the diterpenes zanzibaric acid and isoozic acid were isolated, along with the sesquiterpene caryolane-1,9beta-diol. To the best of our knowledge, this is the first report of this sesquiterpene in the genus. The structures of all compounds isolated were identified on the basis of their spectral data (IR, MS, 1D- and 2D-NMR) and by comparison with literature spectral data.     

Chemical composition, antimicrobial, antiradical and anticholinesterase activity of the essential oil of Pulicaria stephanocarpa from Soqotra

The chemical composition of the hydrodistilled leaf essential oil from Pulicaria stephanocarpa Balf. Fil was determined by GC-MS analysis, and its antimicrobial, antioxidant and anticholinesterase (AChE) activities were evaluated. Eighty-three compounds were identified representing 97.2% of the total oil. (E)-Caryophyllene 13.4%, (E)-nerolidol 8.5%, caryophyllene oxide 8.5%, alpha-cadinol 8.2% spathulenol 6.8% and tau-cadinol 4.7%, were the main components. Antimicrobial activity of the oil, evaluated using the disc diffusion and broth dilution methods, demonstrated the highest susceptibility on Gram-positive bacteria and Candida albicans. The free radical scavenging ability of the oil was assessed by the DPPH assay to show antiradical activity with IC50 of 330 microg/mL. Moreover, the oil revealed an AChE inhibitory activity of 47% at a concentration of 200 microg/mL using Ellman's method.     

Antimicrobial,Mosquito Larvicidal and Antioxidant Properties of the Leaf and Rhizome of Hedychium coronarium

The essential oil, methanolic and aqueous extracts of the leaves and rhizomes of Hedychium coronarium Koen. (Zingiberaceae) were assayed for their antimicrobial, mosquito larvicidal and antioxidant properties. The chemical composition of the essential oil of two organs was analyzed by GC/MS analysis. β‐Pinene (33.9%), α‐pinene (14.7%), 1,8‐cineole (13.3%), r‐elemene (11.0%) and carotol (9.1%) were the main components in the leaf oil, including 82.0% terpenoid compounds. The major constituents of the rhizome oil were 1,8‐cineole (37.3%), β‐pinene (23.0%), α‐terpineol (10.4%) and α‐pinene (9.9%), comprising 80.6% of the oil. The leaf and rhizome essential oil displayed significant antimicrobial activity, as determined by the disc‐diffusion method, inhibiting the growth of all five fungal and four bacterial strains tested. The antimicrobial nature of the essential oil is related to high terpenoid contents. The leaf oil exhibited the mosquito larvicidal activity with 2 h and 24 h LC₅₀ values of 111 and 90 ppm, respectively, while the rhizome oil showed the larvicidal activity with 2 h and 24 h LC₅₀ values of 86 and 47 ppm, respectively. β‐Pinene, α‐pinene and 1,8‐cineol in H. coronarium serve as the principal larvicidal components of both oils. The individual antioxidant assays such as DPPH scavenging activity, chelating effect of ferrous ions and reducing power have been used. The present study demonstrated that the polar extracts of H. coronarium possessed anti‐oxidant. Appreciable total phenolic content (18.5‐26.3 mg/g) was also detected by Folin‐Ciocalteu test.     

Chemical composition, and antioxidant and antimicrobial activities of essential Oil of Phyllostachys heterocycla cv. Pubescens varieties from China

The essential oils of Phyllostachys heterocycla cv. Pubescens, Phyllostachys heterocycla cv. Gracilis, Phyllostachys heterocycla cv. Heterocycla and Phyllostachys kwangsiensis leaves were obtained by steam distillation. Their chemical components were separated and identified by gas chromatography/mass spectrometry (GC/MS). Meanwhile, the effect of scavenging free radicals of essential oil was assayed by using the DPPH·method with Trolox? as control to evaluate their antioxidant capacities. Gram-positive (Staphyloccocus aureus) and Gram-negative (Escherichia coli) were selected as the indicator microorganisms to evaluate the antimicrobial activity. Antimicrobial properties were estimated by the agar diffusion method. The results show that 63 components were separated and identified by GC/MS from these varieties of bamboo leaves. cis-3-Hexenol, whose content in cv. Pubescens, Gracilis, Heterocycla and Ph. kwangsiensis was 27.11%, 24.62%, 30.51% and 34.65%, respectively, was the main constituent. The relative content of alcohol compounds in these varieties of essential oils ranged from 39.8% to 46.64%. All of the bamboo leaf essential oils possessed certain antioxidant capacity; the corresponding IC?? values were 3.1622, 4.9353, 4.2473, and 5.4746 μL/mL, respectively. Essential oils of all tested bamboo spp. were active against Staphylococcus epidermidis and E. coli, showing a positive correlation with the essential oil concentration of 50.42-300 μL/mL. The results indicated there were no significant differences among three varieties and the related species with respect to their antioxidant and antimicrobial activities. This paper provides evidence for studying the essential composition from different varieties of bamboo leaves.     

Comparative analysis by gas chromatography-mass spectrometry of the essential oils from bark and leaves of Cedrelopsis grevei Baill, an aromatic and medicinal plant from Madagascar

The essential oils from bark and leaves of Cedrelopsis grevei Baill (Ptaeroxylaceae), an aromatic and medicinal plant from Madagascar, are widely used in folk medicine. These two commercially available oils have been examined separately by means of GC-MS. The oil constituents were identified according to their mass spectra and their relative retention indices determined on both polar and non-polar stationary phase capillary columns. A total of 55 compounds have been identified constituting 76.7% (bark) and 91.6% (leaves) of the volatile constituents. Both oils were found to have a similar composition; however the relative percentages of some compounds notably differed. The bark essential oil contained beta-pinene (17.1%), cis-sesquisabinene hydrate (12.8%) and caryophyllene oxide (7.0%) as the main components whereas the leaf essential oil was largely dominated by trans-beta-farnesene (35.6%); beta-pinene (12.8%), cis-sesquisabinene hydrate (9.8%) and ar-curcumene (8.6%) were also present as major components. As far as we know, this is the first report on the Cedrelopsis grevei bark and leaf essential oils which therapeutic properties may be attractive for aromatherapy.     

Chemical composition and antimicrobial activity of essential oils from Centaurea pannonica and C. jacea

The chemical composition and antimicrobial activity of the essential oils obtained by hydrodistillation from Centaurea pannonica (Heufel) Simonkai and C. jacea L. (Asteraceae), were investigated. The essential oils were analyzed by GC and GC-MS. Forty five and twenty nine compounds were identified in the two oils, respectively. C. pannonica oil was rich in fatty acids (43.7%), with 9-octadecanoic acid (34.0%) and (Z,Z)-9,12-octadecadienoic acid (8.6%) as the major compounds. In contrast, the essential oil of C. jacea was dominated by oxygenated sesquiterpenes (43.2%), among which caryophyllene oxide (23.5%) and spathulenol (8.9%) were the major constituents. However, the oil was also characterized by an important fatty acid fraction (15.5%), with 9-octadecanoic acid (8.9%) and hexadecanoic acid (6.6%) being the main components. The antimicrobial activities of the essential oils were evaluated by the microdilution method against three Gram-positive and three Gram-negative bacteria, and one yeast. Both oils exhibited significant antimicrobial activity, especially against Gram-positive bacteria.     

The composition and antimicrobial activities of Cyperus conglomeratus, Desmos chinensis var. lawii and Cyathocalyx zeylanicus essential oils

The essential oil compositions of the rhizomes of Cyperus conglomeratus (Cyperaceae) collected from Oman and the leaves of two Annonaceae plants, Desmos chinensis var. lawii and Cyathocalyx zeylanicus collected from India were studied by GC, GC-MS and 13C NMR spectroscopy. Twenty-six compounds, representing 84.4% of the oil were identified in C. conglomeratus, where eugenol (31.3%), alpha-cyperone (10.5%) and cyperotundone (8.4%) were the major compounds. Twelve compounds, constituting 100%, were identified in D. lawii oil, of which benzyl benzoate (58.7%), beta-caryophyllene (23.2%), limonene (4.9%) and alpha-humulene (4.0%) were the major constituents. Thirty-two compounds, comprising 98.0%, were identified in C. zeylanicus oil, of which beta-caryophyllene (21.6%), alpha-pinene (20.4%) and E-beta-ocimene (11.8%) were the major components. The antibacterial and antifungal activities of the oils were tested against a panel of five bacterial and two fungal strains. The oils showed moderate activity against all the tested microbial strains. The minimum inhibitory concentrations of the oils were also determined.     

Chemical composition and antimicrobial activity of some oleogum resin essential oils from Boswellia spp. (Burseraceae)

The chemical composition of Boswellia carteri (Somalia), B. papyrifera (Ethiopia), B. serrata (India) and B. rivae (Ethiopia) oleogum resin essential oils was investigated using GC-MS to identify chemotaxonomy marker components. Total ion current peak areas gave good approximations to relative concentrations based on GC-MS peak areas. B. carteri and B. serrata oleogum resin oils showed similar chemical profiles, with isoincensole and isoincensole acetate as the main diterpenic components. Both n-octanol and n-octyl acetate, along with the diterpenic components incensole and incensole acetate, were the characteristic compounds of B. papyrifera oleogum resin oil. Hydrocarbon and oxygenated monoterpenes were the most abundant classes of compounds identified in the B. rivae oleogum resin oil. The antimicrobial activities of the essential oils were individually evaluated against different microorganisms including fungi, Gram-positive and Gram-negative bacteria strains. The essential oils with the best activity against fungal strains were those obtained from B. carteri and B. papyrifera with MIC values as low as 6.20 microg/ml. The essential oil of B. rivae resin showed the best activity against C. albicans with a MIC value of 2.65 microg/ml.