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Yu-chang Su - One of the best experts on this subject based on the ideXlab platform.

  • Composition and antifungal activities of the leaf essential oil of Neolitsea parvigemma from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Pei-chun Liao, Eugene I-chen Wang, Yu-chang Su
    Abstract:

    : 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 activity of the leaf and twig oils of Litsea mushaensis and L. linii from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Pei-chun Liao, Eugene I-chen Wang, Yen-hsueh Tseng, Ju-ching Chou, Yu-chang Su
    Abstract:

    : 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 and antimicrobial activity of the leaf essential oil of Litsea kostermansii from Taiwan.
    Natural product communications, 2020
    Co-Authors: Chen-lung Ho, Eugene I-chen Wang, Yu-chang Su
    Abstract:

    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 Beta-Eudesmol (22.5%), gamma-Eudesmol (18.6%), delta-selinene (8.5%), alpha-Eudesmol (6.0%), and gamma-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 activities of the leaf essential oil of Machilus kusanoi from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Pei-chun Liao, Eugene I-chen Wang, Yen-hsueh Tseng, Ju-ching Chou, Yu-chang Su
    Abstract:

    : 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, antioxidant, antimicrobial and anti-wood-decay fungal activities of the twig essential oil of Taiwania cryptomerioides from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Su Sing Yang, Tsong-min Chang, Yu-chang Su
    Abstract:

    : 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.

Masayasu Kimura - One of the best experts on this subject based on the ideXlab platform.

  • Noncontractile acetylcholine receptor-operated Ca++ mobilization: suppression of activation by open channel blockers and acceleration of desensitization by closed channel blockers in mouse diaphragm muscle.
    Journal of Pharmacology and Experimental Therapeutics, 1991
    Co-Authors: Masayasu Kimura, I Kimura, T Kondoh, H Tsuneki
    Abstract:

    The effects of various blockers of the nicotinic acetylcholine receptor-activated ionic channel on noncontractile slow Ca++ mobilization were investigated at the neuromuscular synapse of aequorin-injected diaphragm muscles of mice. Intracellular Ca++ mobilization (Ca++ transients) was evoked in the presence of neostigmine (0.3 microM) by nerve stimulation. Bupivacaine, an open channel blocker, decreased the peak amplitude, whereas chlorpromazine, a closed channel blocker, shortened the duration. Phencyclidine, an open and closed channel blocker, decreased both peak amplitude and duration. Beta-Eudesmol, a compound of Atractylodes lancea, clearly and specifically shortened the duration but had little effect on peak amplitude. All the above channel blockers, when given in the same concentration ranges, also blocked the total amount of contractile Ca++ transients. The effects of bupivacaine, chlorpromazine and phencyclidine on noncontractile Ca++ transients were not affected by 5 mM [Ca++]o, whereas the effect of Beta-Eudesmol was enhanced. Geographutoxin II (0.3 microM), a skeletal muscle Na+ channel blocker, selectively and partly reversibly blocked contractile Ca++ transients without affecting noncontractile ones. These results suggest that: 1) the activation of noncontractile Ca++ mobilization is suppressed by open channel blockers, whereas its desensitization is accelerated by closed channel blockers and 2) activation of the muscle Na+ channel and subsequent release of Ca++ from sarcoplasmic reticulum is not involved in the mechanism of noncontractile Ca++ mobilization. It may reflect the steps of the desensitization process.

  • enhancing effect by nicotinic acetylcholine receptor channel blockers including Beta Eudesmol on succinylcholine induced inhibition of twitch tension and intracellular ca in mouse diaphragm muscle
    Journal of Pharmacology and Experimental Therapeutics, 1991
    Co-Authors: I Kimura, H Tsuneki, T Kondoh, Masayasu Kimura
    Abstract:

    To elucidate the mechanism of neuromuscular block by succinylcholine, nerve-evoked changes in intracellular Ca(++)-aequorin luminescence and twitch tension were measured simultaneously in the presence of several different types of blockers for the nicotinic acetylcholine receptor channel. Mouse diaphragm muscles were pretreated for 30 to 60 min with 3 to 40 microM bupivacaine, chlorpromazine, phencyclidine and Beta-Eudesmol. The effects of these noncompetitive blockers on the succinylcholine-induced response were also compared with those for pancuronium. These channel blockers potentiated (2- to 10-fold) both the blocking effects on intracellular Ca++ and twitch tension of succinylcholine (13-100 microM), but not the pancuronium (0.3-1.1 microM)-induced block. These channel blockers also suppressed succinylcholine (1.3-5 microM)-induced enhancement of evoked Ca++ transients. On the other hand, the channel blockers inhibited the succinylcholine (2.5-100 microM)-induced increase in basal Ca++ transients. These results suggest that neuromuscular block induced by succinylcholine is mainly due to desensitization of the nicotinic acetylcholine receptor.

Chen-lung Ho - One of the best experts on this subject based on the ideXlab platform.

  • Composition and antifungal activities of the leaf essential oil of Neolitsea parvigemma from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Pei-chun Liao, Eugene I-chen Wang, Yu-chang Su
    Abstract:

    : 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 activity of the leaf and twig oils of Litsea mushaensis and L. linii from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Pei-chun Liao, Eugene I-chen Wang, Yen-hsueh Tseng, Ju-ching Chou, Yu-chang Su
    Abstract:

    : 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 and antimicrobial activity of the leaf essential oil of Litsea kostermansii from Taiwan.
    Natural product communications, 2020
    Co-Authors: Chen-lung Ho, Eugene I-chen Wang, Yu-chang Su
    Abstract:

    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 Beta-Eudesmol (22.5%), gamma-Eudesmol (18.6%), delta-selinene (8.5%), alpha-Eudesmol (6.0%), and gamma-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 activities of the leaf essential oil of Machilus kusanoi from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Pei-chun Liao, Eugene I-chen Wang, Yen-hsueh Tseng, Ju-ching Chou, Yu-chang Su
    Abstract:

    : 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, antioxidant, antimicrobial and anti-wood-decay fungal activities of the twig essential oil of Taiwania cryptomerioides from Taiwan.
    Natural Product Communications, 2020
    Co-Authors: Chen-lung Ho, Su Sing Yang, Tsong-min Chang, Yu-chang Su
    Abstract:

    : 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.

I Kimura - One of the best experts on this subject based on the ideXlab platform.

  • Noncontractile acetylcholine receptor-operated Ca++ mobilization: suppression of activation by open channel blockers and acceleration of desensitization by closed channel blockers in mouse diaphragm muscle.
    Journal of Pharmacology and Experimental Therapeutics, 1991
    Co-Authors: Masayasu Kimura, I Kimura, T Kondoh, H Tsuneki
    Abstract:

    The effects of various blockers of the nicotinic acetylcholine receptor-activated ionic channel on noncontractile slow Ca++ mobilization were investigated at the neuromuscular synapse of aequorin-injected diaphragm muscles of mice. Intracellular Ca++ mobilization (Ca++ transients) was evoked in the presence of neostigmine (0.3 microM) by nerve stimulation. Bupivacaine, an open channel blocker, decreased the peak amplitude, whereas chlorpromazine, a closed channel blocker, shortened the duration. Phencyclidine, an open and closed channel blocker, decreased both peak amplitude and duration. Beta-Eudesmol, a compound of Atractylodes lancea, clearly and specifically shortened the duration but had little effect on peak amplitude. All the above channel blockers, when given in the same concentration ranges, also blocked the total amount of contractile Ca++ transients. The effects of bupivacaine, chlorpromazine and phencyclidine on noncontractile Ca++ transients were not affected by 5 mM [Ca++]o, whereas the effect of Beta-Eudesmol was enhanced. Geographutoxin II (0.3 microM), a skeletal muscle Na+ channel blocker, selectively and partly reversibly blocked contractile Ca++ transients without affecting noncontractile ones. These results suggest that: 1) the activation of noncontractile Ca++ mobilization is suppressed by open channel blockers, whereas its desensitization is accelerated by closed channel blockers and 2) activation of the muscle Na+ channel and subsequent release of Ca++ from sarcoplasmic reticulum is not involved in the mechanism of noncontractile Ca++ mobilization. It may reflect the steps of the desensitization process.

  • enhancing effect by nicotinic acetylcholine receptor channel blockers including Beta Eudesmol on succinylcholine induced inhibition of twitch tension and intracellular ca in mouse diaphragm muscle
    Journal of Pharmacology and Experimental Therapeutics, 1991
    Co-Authors: I Kimura, H Tsuneki, T Kondoh, Masayasu Kimura
    Abstract:

    To elucidate the mechanism of neuromuscular block by succinylcholine, nerve-evoked changes in intracellular Ca(++)-aequorin luminescence and twitch tension were measured simultaneously in the presence of several different types of blockers for the nicotinic acetylcholine receptor channel. Mouse diaphragm muscles were pretreated for 30 to 60 min with 3 to 40 microM bupivacaine, chlorpromazine, phencyclidine and Beta-Eudesmol. The effects of these noncompetitive blockers on the succinylcholine-induced response were also compared with those for pancuronium. These channel blockers potentiated (2- to 10-fold) both the blocking effects on intracellular Ca++ and twitch tension of succinylcholine (13-100 microM), but not the pancuronium (0.3-1.1 microM)-induced block. These channel blockers also suppressed succinylcholine (1.3-5 microM)-induced enhancement of evoked Ca++ transients. On the other hand, the channel blockers inhibited the succinylcholine (2.5-100 microM)-induced increase in basal Ca++ transients. These results suggest that neuromuscular block induced by succinylcholine is mainly due to desensitization of the nicotinic acetylcholine receptor.

Ekaterina Jeliazkova - One of the best experts on this subject based on the ideXlab platform.

  • Year-round Variations in Essential Oil Content and Composition of Male and
    2020
    Co-Authors: Valtcho D. Zheljazkov, Tess Astatkie, Nova Scotia, Ekaterina Jeliazkova
    Abstract:

    Rocky Mountain juniper (Juniperus scopulorum Sarg.) is an evergreen dioecious tree(producesmaleandfemaleplants).Thepleasantaromaandthemedicinalvalueofthis species are the result of the essential oil. The hypothesis of this study was that the essential oil content and composition may be different in male and in female trees and also may be affected with seasonal changes throughout the year. The objective was to evaluate year- roundvariationsinessentialoilcompositionofRockyMountainjuniperwithinsingle male and female trees. The concentration of essential oil in fresh leaves varied from 0.335% to 0.799%, and at most sampling points, the oil content in the biomass of the male tree was greater than that in the biomass of the female tree. There was a trend toward increased essential oil content in male juniper in 220 to 342 days after the first sampling (DAFS), compared withthe onein35 to184DAFS. The concentrationsofthe oilconstituentsalpha- pinene, alpha-terpinene, gamma-terpinene, terpinolene, pregeijerene B, elemol, Beta- Eudesmol/alpha-Eudesmol, and 8-alpha-acetoxyelemol were greater in the oil of the female tree than in the oil of the male tree. Conversely, the concentrations of alpha thujene, sabinene, myrcene, limonene, and delta-cadinene were greater in the oil of the male tree than in the oil of the female tree. However, the concentration gradient trends for both female and male trees were similar for myrcene and sabinene, for alpha-terpinene and terpinolene, for pereijerene B and elemol, and for Beta-Eudesmol/alpha-Eudesmol and 8-alpha-acetoxyelemol. Overall, lower concentrations in the oils at 101 to 132 or 163 DAFS were found for myrcene and alpha-pinene sabinene, whereas the concentrations of gamma-terpinene, elemol (female tree), Beta-Eudesmol/alpha-Eudesmol (female tree), and 8- alpha-acetoxyelemol (female tree) were greater during this period. This study demon- strated that the content and composition of the essential oil from Rocky Mountain juniper are subject to seasonal changes and also depend on the sex of the tree.

  • Year-round Variations in Essential Oil Content and Composition of Male and Female Juniper
    Hortscience, 2013
    Co-Authors: Valtcho D. Zheljazkov, Tess Astatkie, Ekaterina Jeliazkova
    Abstract:

    Rocky Mountain juniper (Juniperus scopulorum Sarg.) is an evergreen dioecious tree (produces male and female plants). The pleasant aroma and the medicinal value of this species are the result of the essential oil. The hypothesis of this study was that the essential oil content and composition may be different in male and in female trees and also may be affected with seasonal changes throughout the year. The objective was to evaluate yearround variations in essential oil composition of Rocky Mountain juniper within single male and female trees. The concentration of essential oil in fresh leaves varied from 0.335% to 0.799%, and at most sampling points, the oil content in the biomass of the male tree was greater than that in the biomass of the female tree. There was a trend toward increased essential oil content in male juniper in 220 to 342 days after the first sampling (DAFS), compared with the one in 35 to 184 DAFS. The concentrations of the oil constituents alphapinene, alpha-terpinene, gamma-terpinene, terpinolene, pregeijerene B, elemol, BetaEudesmol/alpha-Eudesmol, and 8-alpha-acetoxyelemol were greater in the oil of the female tree than in the oil of the male tree. Conversely, the concentrations of alpha thujene, sabinene, myrcene, limonene, and delta-cadinene were greater in the oil of the male tree than in the oil of the female tree. However, the concentration gradient trends for both female and male trees were similar for myrcene and sabinene, for alpha-terpinene and terpinolene, for pereijerene B and elemol, and for Beta-Eudesmol/alpha-Eudesmol and 8-alpha-acetoxyelemol. Overall, lower concentrations in the oils at 101 to 132 or 163 DAFS were found for myrcene and alpha-pinene sabinene, whereas the concentrations of gamma-terpinene, elemol (female tree), Beta-Eudesmol/alpha-Eudesmol (female tree), and 8alpha-acetoxyelemol (female tree) were greater during this period. This study demonstrated that the content and composition of the essential oil from Rocky Mountain juniper are subject to seasonal changes and also depend on the sex of the tree. Rocky Mountain juniper (Juniperus scopulorum Sarg.), an evergreen dioecious gymnosperm, is a widespread species in the western United States (Arizona, Colorado, Idaho, Montana, North Dakota, Nebraska, New Mexico, Nevada, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, and Wyoming) and is found in Canada and in Mexico (Adams, 2004; Scher, 2002; USDA, 2011). Despite the wide ecological adaption, Rocky Mountain juniper is not a primary source for lumber because of relatively slow growth. However, Rocky Mountain juniper wood is highly valued for its durability, rich color, pleasant aroma, antioxidant activity, and is extensively used for interior paneling, furniture, various novelties, and fence posts. The species has been used extensively in the ethnobotany of native people of North America to treat a number of medical conditions. Native people of North America have been using the leaves as medicine and the wood for preparation of bows, lances, flutes, and other important items (Hart, 1976; Kroeber, 1908). Rocky Mountain juniper is also an important species in the arid and semiarid regions of North America for a number of wildlife species such as deer, elk, small mammals, and birds, which use it for cover and a food source (Rumble and Gobeille, 2013; Scher, 2002). These animals play a major role in seed dispersal. Rocky Mountain juniper leaves contain a significant amount of strongly aromatic essential oil, which has been subject to some previous studies (Adams and Hagerman, 1977; Adams and Powell, 1976; Cantrell et al., 2013; Zheljazkov et al., 2012a, 2012b). Previous investigations have found that sexual differences (Adams and Powell, 1976), seasonal changes (Powell and Adams, 1973), diurnal variations (Adams, 1979), and duration of distillation time (Zheljazkov et al., 2012a, 2012b) can affect Rocky Mountain juniper essential oil composition. However, there are no reports on variations of Rocky Mountain juniper essential oil yearround, from within a single tree, and on whether there are any seasonal differences between the composition of essential oil obtained from male and female trees grown side by side. Therefore, the objective of this study was to evaluate year-round variations in essential oil composition of Rocky Mountain juniper within one male and one female trees. Materials and Methods Plant material and essential oil steam distillation. All samples used in this study were generated from two adjacent large Rocky Mountain junipers (tree #470 male and tree #471 female) situated at the University of Wyoming Sheridan Research and Extension Center (ShREC) (lat. 44 50.373# N, long. 106 50.396# W, elevation 1140 m above sea level). Both trees were planted as part of a windbreak project at ShREC initiated by the U.S. Department of Agriculture in 1915 to 1917. Samples from the two trees were identified as specimens of Rocky Mountain juniper by Ms. Bonnie Heidel, botanist at the Wyoming Natural Diversity Database. All samples for distillation were generated in early morning ( 0800 HR) and distilled fresh. Sample size for each distillation was 500 g of fresh material in all three replicates. Rocky Mountain junipers (both male and the female trees) were sampled each month starting 12 Apr. 2011 and finishing on 19 Mar. 2012; there were 12 sampling points at the following DAFS: 1, 35, 62, 80, 101, 132, 163, 184, 220, 246, 286, 314, and 342. These DAFS correspond to 12 Apr. 2011, 17 May 2011, 13 June 2011, 1 July 2011, 22 July 2011, 22 Aug. 2011, 22 Sept. 2011, 13 Oct. 2011, 18 Nov. 2011, 14 Dec. 2011, 23 Jan. 2012, 20 Feb. 2012, and 19 Mar. 2012, respectively. The steam distillations were conducted as described previously (Zheljazkov et al., 2012a). Briefly, 500 g of fresh samples (collected at different heights and from different sides of the tree) were chopped into 2.5-cm pieces and immediately distilled in 2-L steam Received for publication 30 Apr. 2013. Accepted for publication 29 May 2013. This research was funded by the University of Wyoming startup funding and the Department of Plant Science allocation awarded to Dr. V. Zheljazkov. We thank Mrs. Adrienne Tatman, Mrs. Burnnie Foulke, Ms. Berva Brock, and Mrs. Leanne Roadifer for their help with the harvesting of the biomass and the extraction of the essential oil in the laboratory. We thank Dr. Mason MacDonald of Dalhousie University and Mrs. Rochelle Koltiska of the University of Wyoming for proof reading the manuscript internally and offering many suggestions. To whom reprint requests should be addressed; e-mail vjeliazk@uwyo.edu, Valtcho.pubs@gmail. com. HORTSCIENCE VOL. 48(7) JULY 2013 883 | POSTHARVEST BIOLOGY AND TECHNOLOGY

  • Distillation time alters essential oil yield, composition and antioxidant activity of female Juniperus scopulorum trees
    Journal of Essential Oil Research, 2013
    Co-Authors: Valtcho D. Zheljazkov, Tess Astatkie, Ekaterina Jeliazkova, Adrienne O. Tatman, Vicki Schlegel
    Abstract:

    The objective of this study was to evaluate the effect of distillation time (DT) (1.25, 2.5, 5, 10, 20, 40, 80, 160, 240, 360, 480 minutes) on yield, oil profile and antioxidant capacity of female Juniperus scopulorum trees. Analysis of the data revealed that essential oil yields reached a maximum of 0.77% at 240 minutes DT; the concentrations of alpha-thujene, alpha-pinene, camphene, myrcene and para-cymene decreased with longer DT; and the concentrations of cis-sabinene hydrate and linalool/trans-sabinene hydrate reached maximum at 40 minutes DT, whereas that of pregeijerene-B, delta-carene reached maximum at 240 minutes DT. The concentrations of alpha-terpinene, limonene, gamma-terpinene and 4-terpineol reached their maximum at 360 minutes DT, whereas terpinolene, alpha-Eudesmol/Beta-Eudesmol and 8-alpha acetoxyelemol reached maximum at 480 minutes DT. The yield of various essential oil constituents increased with increasing DT and reached maximum at 240 minutes or longer. The antioxidant capacity of J...