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Roger A. Laine - One of the best experts on this subject based on the ideXlab platform.
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Structural requirements for repellency: norsesquiterpenes and sesquiterpenoid derivatives of Nootkatone against the Formosan subterranean termite (Isoptera: Rhinotermitidae).
Pest management science, 2010Co-Authors: Betty C. R. Zhu, Gregg Henderson, Anne M. Sauer, William E. Crowe, Roger A. LaineAbstract:BACKGROUND: Research has shown that the family of grapefruit flavors called Nootkatones have significant repellant and toxic effects to Formosan subterranean termites (Coptotermes formosanus Shiraki). RESULTS: Nineteen synthetic Nootkatone derivatives, along with three commercially available Nootkatone derivatives, were tested for repellent activity against C. formosanus by a choice assay in a petri dish with a two-step triage procedure. Based on the repellency threshold value, the relationships between structure and activity are discussed. CONCLUSION: Four derivatives of Nootkatone have very high repellency and toxicity to C. formosanus, 9 times the potency of the primary compound Nootkatone. Four other compounds have between 2 and 3 times the repellency of Nootkatones, and three compounds are equal in their repellency to Nootkatone.
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An efficient and economic asymmetric synthesis of (+)-Nootkatone, tetrahydroNootkatone, and derivatives.
Organic letters, 2009Co-Authors: Anne M. Sauer, Gregg Henderson, William E. Crowe, Roger A. LaineAbstract:A facile route to enantiomerically pure (+)-Nootkatone and derivatives has been established through conjunctive stereoselective Grignard/anionic oxy-Cope (AOC) reactions.
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an efficient and economic asymmetric synthesis of Nootkatone tetrahydroNootkatone and derivatives
Organic Letters, 2009Co-Authors: Anne M. Sauer, Gregg Henderson, William E. Crowe, Roger A. LaineAbstract:A facile route to enantiomerically pure (+)-Nootkatone and derivatives has been established through conjunctive stereoselective Grignard/anionic oxy-Cope (AOC) reactions.
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Potential target site activity of Nootkatone and tetrahydroNootkatone on formosan subterranean termite (Isoptera: Rhinotermitidae).
2007Co-Authors: Sanaa A. Ibrahim, R. Cross, Sun Jianzhong, Roger A. Laine, Gregg Henderson, K. Z. AhmedAbstract:Nootkatone, an eudalenoid sesquiterpene ketone present in citrus oil, Alaskan yellow cedar, and vetiver oil, and a derivative, tetrahydroNootkatone, were toxic and caused behavioral lethargy (“lingering”) in Coptotermes formosanus Shiraki. Four biologically active doses of Nootkatone and tetrahydroNootkatone (LD25 (24 h lethal dose for 25% of workers), LD50, LD90 and 2-fold the LD90) were established with workers from two colonies and in vitro evaluated for their effects on workerand soldier-acetylcholinesterase activity (AChE). Significant interand intracolony variation in AChE activity and sensitivity toward the tested chemicals were observed. The stimulating effect of tetrahydroNootkatone on worker and soldier AChE activity was dose and colony dependent. The interference of Nootkatone with worker AChE fluctuated from slight inhibition to significant activation. Nootkatone did not significantly affect soldier enzyme activity even at the LD90*2. AChE stimulating effects were highly correlated with toxicity of tetrahydroNootkatone (R = 0.9856 and P = 0.0003), but not with Nootkatone toxicity (R = 0.5783, P = 0.2292). Increased AChE activity may explain the lingering behavior observed with Nootkatone and tetrahydroNootkatone treated termites.
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Vetiver oil and Nootkatone effects on the growth of pea and citrus
Industrial Crops and Products, 2006Co-Authors: Lixin Mao, Gregg Henderson, Wayne J. Bourgeois, J. Alan Vaughn, Roger A. LaineAbstract:Abstract Studies have indicated that vetiver oil and one of its components, Nootkatone, possess insecticidal and herbicidal activities. The compounds appear to be good candidates as novel pesticides for substrate (soil, wood, and mulch) treatments. Phytotoxicity is a concern for substrate treatment agents against soil dwelling organisms. Using treated potting media the phytotoxic effect of vetiver oil and Nootkatone was evaluated on the pea plants ( Pisum sativum L.; cv, “Kelvedon Wonder”) in the laboratory and on citrus trees ( Citrus unshiu Marcovitch) under field conditions. All the tested chemicals at various concentrations (20, 500, and 2000 μg/g soil) reduced the pea plant growth (plant height, root length, dry weight). Nootkatone treatments had the lowest inhibitory effect on growth, followed by vetiver oil and disodium octaborate tetrahydrate (Tim-bor ® ), a registered pesticide with known phytotoxicity. The most inhibitive and injurious effects occurred with Tim-bor ® at concentrations of 500 and 2000 μg/g soil, causing plant mortality of up to 38.9%. No pea plant mortality was observed in Nootkatone and vetiver oil treatments. Vetiver oil and Nootkatone treatments at the rates of 30 and 100 μg/g potting media had no adverse effect on the citrus plant growth rates. These results support the possible usage of the two chemicals around buildings and in nurseries for the management of termites, ants, and weeds; or in the nursery industry where quarantines may be in place to prevent the movement of invasive pests.
Gregg Henderson - One of the best experts on this subject based on the ideXlab platform.
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evaluation of potential use of Nootkatone against maize weevil sitophilus zeamais motschulsky and rice weevil s oryzae l coleoptera curculionidae
Journal of Stored Products Research, 2010Co-Authors: Gregg HendersonAbstract:Abstract Nootkatone is a natural sesquiterpene ketone that shows insecticidal activity against insects and ticks. Its contact toxicity and repellency against two major stored-product insect pests, maize weevil ( Sitophilus zeamais Motschulsky) and rice weevil [ Sitophilus oryzae (L.)], were investigated in the current study. Contact toxicity was evaluated using a no-choice test with treated filter paper, while repellency was evaluated using a choice test with treated corn (for maize weevils) or wheat (for rice weevils). Nootkatone showed low contact toxicity (ranging from 0 to 51%) against the two weevil species at the tested concentrations (ranging from 11.58 μg/cm 2 to 1158.08 μg/cm 2 ) on filter papers. In choice tests, corn treated with 0.10% or higher and wheat treated with 0.5% Nootkatone or higher had significantly fewer maize or rice weevils compared with the solvent only treated control, indicating a repellent effect. The repellency percentage ranged between 46.3 and 93.1% against maize weevils and 39.2–67.2% for rice weevils.
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Structural requirements for repellency: norsesquiterpenes and sesquiterpenoid derivatives of Nootkatone against the Formosan subterranean termite (Isoptera: Rhinotermitidae).
Pest management science, 2010Co-Authors: Betty C. R. Zhu, Gregg Henderson, Anne M. Sauer, William E. Crowe, Roger A. LaineAbstract:BACKGROUND: Research has shown that the family of grapefruit flavors called Nootkatones have significant repellant and toxic effects to Formosan subterranean termites (Coptotermes formosanus Shiraki). RESULTS: Nineteen synthetic Nootkatone derivatives, along with three commercially available Nootkatone derivatives, were tested for repellent activity against C. formosanus by a choice assay in a petri dish with a two-step triage procedure. Based on the repellency threshold value, the relationships between structure and activity are discussed. CONCLUSION: Four derivatives of Nootkatone have very high repellency and toxicity to C. formosanus, 9 times the potency of the primary compound Nootkatone. Four other compounds have between 2 and 3 times the repellency of Nootkatones, and three compounds are equal in their repellency to Nootkatone.
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An efficient and economic asymmetric synthesis of (+)-Nootkatone, tetrahydroNootkatone, and derivatives.
Organic letters, 2009Co-Authors: Anne M. Sauer, Gregg Henderson, William E. Crowe, Roger A. LaineAbstract:A facile route to enantiomerically pure (+)-Nootkatone and derivatives has been established through conjunctive stereoselective Grignard/anionic oxy-Cope (AOC) reactions.
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an efficient and economic asymmetric synthesis of Nootkatone tetrahydroNootkatone and derivatives
Organic Letters, 2009Co-Authors: Anne M. Sauer, Gregg Henderson, William E. Crowe, Roger A. LaineAbstract:A facile route to enantiomerically pure (+)-Nootkatone and derivatives has been established through conjunctive stereoselective Grignard/anionic oxy-Cope (AOC) reactions.
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Potential target site activity of Nootkatone and tetrahydroNootkatone on formosan subterranean termite (Isoptera: Rhinotermitidae).
2007Co-Authors: Sanaa A. Ibrahim, R. Cross, Sun Jianzhong, Roger A. Laine, Gregg Henderson, K. Z. AhmedAbstract:Nootkatone, an eudalenoid sesquiterpene ketone present in citrus oil, Alaskan yellow cedar, and vetiver oil, and a derivative, tetrahydroNootkatone, were toxic and caused behavioral lethargy (“lingering”) in Coptotermes formosanus Shiraki. Four biologically active doses of Nootkatone and tetrahydroNootkatone (LD25 (24 h lethal dose for 25% of workers), LD50, LD90 and 2-fold the LD90) were established with workers from two colonies and in vitro evaluated for their effects on workerand soldier-acetylcholinesterase activity (AChE). Significant interand intracolony variation in AChE activity and sensitivity toward the tested chemicals were observed. The stimulating effect of tetrahydroNootkatone on worker and soldier AChE activity was dose and colony dependent. The interference of Nootkatone with worker AChE fluctuated from slight inhibition to significant activation. Nootkatone did not significantly affect soldier enzyme activity even at the LD90*2. AChE stimulating effects were highly correlated with toxicity of tetrahydroNootkatone (R = 0.9856 and P = 0.0003), but not with Nootkatone toxicity (R = 0.5783, P = 0.2292). Increased AChE activity may explain the lingering behavior observed with Nootkatone and tetrahydroNootkatone treated termites.
Jie Sun - One of the best experts on this subject based on the ideXlab platform.
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heterologous biosynthesis of Nootkatone in unconventional yeast yarrowia lipolytica
Biochemical Engineering Journal, 2018Co-Authors: Xiaoyan Guo, Jie SunAbstract:Abstract Yarrowia lipolytica is an unconventional yeast that is regarded as safe. It is the potential platform for terpenoids production because it possesses the endogenous MVA pathway which can provide precursors for terpenoids synthesis. Herein, we constructed (+)-Nootkatone, a sesquiterpenoid which is highly demanded in cosmetics and fragrance industries, synthetic pathway in Yarrowia lipolytica ATCC 201249. Heterologous production of (+)-Nootkatone was achieved by co-expressing (+)-valencene synthase CnVS, codon-optimized (+)-Nootkatone synthase opCYP706M1 and codon-optimized NADPH-cytochrome P450 reductase opAtCPR1. The initial (+)-Nootkatone production was 45.6 μg/L. Fusion of opCYP706M1 and opt46AtCPR1 (opAtCPR1 with 46 amino acids truncated at N-terminal) increased (+)-valencene conversion efficiency to (+)-Nootkatone and (+)-Nootkatone production increased to 312.2 μg/L, nearly six times higher than the initial. Overexpression of the MVA pathway rate limiting enzymes 3-hydroxy-3-methylglutaryl-coenzyme A reductase tHMG1 and FPP synthase ERG20 improved the (+)-Nootkatone production furtherly. The final engineered strain achieved a (+)-Nootkatone titer of 978.2 μg/L, which was a 20.5-fold increase compared to those simply coexpressed CnVS, opCYP706M1 and opAtCPR1. This is the first report of heterologous biosynthesis of (+)-Nootkatone in Y. lipolytica, which will provide a favorable reference for studies on heterologous production of other sesquiterpenoids and high-efficiency expression of P450 enzymes in Y. lipolytica.
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Heterologous biosynthesis of (+)-Nootkatone in unconventional yeast Yarrowia lipolytica
Biochemical Engineering Journal, 2018Co-Authors: Xiaoyan Guo, Jie SunAbstract:Abstract Yarrowia lipolytica is an unconventional yeast that is regarded as safe. It is the potential platform for terpenoids production because it possesses the endogenous MVA pathway which can provide precursors for terpenoids synthesis. Herein, we constructed (+)-Nootkatone, a sesquiterpenoid which is highly demanded in cosmetics and fragrance industries, synthetic pathway in Yarrowia lipolytica ATCC 201249. Heterologous production of (+)-Nootkatone was achieved by co-expressing (+)-valencene synthase CnVS, codon-optimized (+)-Nootkatone synthase opCYP706M1 and codon-optimized NADPH-cytochrome P450 reductase opAtCPR1. The initial (+)-Nootkatone production was 45.6 μg/L. Fusion of opCYP706M1 and opt46AtCPR1 (opAtCPR1 with 46 amino acids truncated at N-terminal) increased (+)-valencene conversion efficiency to (+)-Nootkatone and (+)-Nootkatone production increased to 312.2 μg/L, nearly six times higher than the initial. Overexpression of the MVA pathway rate limiting enzymes 3-hydroxy-3-methylglutaryl-coenzyme A reductase tHMG1 and FPP synthase ERG20 improved the (+)-Nootkatone production furtherly. The final engineered strain achieved a (+)-Nootkatone titer of 978.2 μg/L, which was a 20.5-fold increase compared to those simply coexpressed CnVS, opCYP706M1 and opAtCPR1. This is the first report of heterologous biosynthesis of (+)-Nootkatone in Y. lipolytica, which will provide a favorable reference for studies on heterologous production of other sesquiterpenoids and high-efficiency expression of P450 enzymes in Y. lipolytica.
Betty C. R. Zhu - One of the best experts on this subject based on the ideXlab platform.
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Structural requirements for repellency: norsesquiterpenes and sesquiterpenoid derivatives of Nootkatone against the Formosan subterranean termite (Isoptera: Rhinotermitidae).
Pest management science, 2010Co-Authors: Betty C. R. Zhu, Gregg Henderson, Anne M. Sauer, William E. Crowe, Roger A. LaineAbstract:BACKGROUND: Research has shown that the family of grapefruit flavors called Nootkatones have significant repellant and toxic effects to Formosan subterranean termites (Coptotermes formosanus Shiraki). RESULTS: Nineteen synthetic Nootkatone derivatives, along with three commercially available Nootkatone derivatives, were tested for repellent activity against C. formosanus by a choice assay in a petri dish with a two-step triage procedure. Based on the repellency threshold value, the relationships between structure and activity are discussed. CONCLUSION: Four derivatives of Nootkatone have very high repellency and toxicity to C. formosanus, 9 times the potency of the primary compound Nootkatone. Four other compounds have between 2 and 3 times the repellency of Nootkatones, and three compounds are equal in their repellency to Nootkatone.
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Toxicity and Behavioral Effects of Nootkatone, 1,10-DihydroNootkatone, and TetrahydroNootkatone to the Formosan Subterranean Termite (Isoptera: Rhinotermitidae)
Journal of economic entomology, 2004Co-Authors: Sanaa A. Ibrahim, Gregg Henderson, Betty C. R. Zhu, Huixin Fei, Roger A. LaineAbstract:Toxicity and behavioral effects of Nootkatone and two of its derivatives, 1,10-dihydroNootkatone and tetrahydroNootkatone, to Coptotermes formosanus Shiraki were investigated on workers from two different colonies by using topical application assays, repellency assays, and sand barrier assays. The acute toxicity of the Nootkatones on workers from both colonies increased as the saturation of the molecule increased, but the difference was significant for only one colony. The results of the repellency assays showed a similar trend of efficiency; the threshold concentration for significant repellency was four-fold higher in Nootkatone treatments (50 ppm) than in the reduced derivatives 1,10-dihydroNootkatone or tetrahydroNootkatone (12.5 ppm). In sand barrier assays, a concentration of 100 ppm of any of the three chemicals significantly reduced termite survival, tunnel building, and food consumption after a 12-d exposure. Termites preexposed to100 ppm Nootkatone-treated sand and placed in containers without Nootkatone for 15 d continued to exhibit abnormal feeding and digging behaviors; survivorship, tunneling, and feeding activities were significantly reduced by 83.5, 63.2, and 95.4%, respectively. Termites pretreated for 12 d at concentrations of 50 and 75 ppm Nootkatone and tetrahydroNootkatone returned to normal digging activity after they were removed from the treatments, but their feeding activity was significantly reduced.
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Structure–Activity of Valencenoid Derivatives and Their Repellence to the Formosan Subterranean Termite
Journal of Chemical Ecology, 2003Co-Authors: Betty C. R. Zhu, Gregg Henderson, Anne M. Sauer, William Crowe, Roger A. LaineAbstract:Eight valencenoid derivatives were evaluated for their repelling activity against Formosan subterranean termites, Coptotermes formosanus Shiraki. Among them, 1,10-dihydroNootkatone was the strongest repellent, and valencene was the weakest. Results of the structure–repellency relationships indicated (1) reduction of the ketone group to the alcohol on position 2 of Nootkatone curtailed the activity; (2) because of the low activity of valencene relative to Nootkatone that the ketone group was essential for repellent activity; (3) reduction of the 1,10 double bond (1,10-dihydroNootkatone and tetrahydroNootkatone) produced compounds more repellent than Nootkatone; (4) the isopropenyl group probably does not participate in binding as evidenced by no significant difference in the repellent activity among Nootkatone (double bond between position 11 and 12), isoNootkatone (double bond between position 7 and 11), and 11,12-dihydroNootkatone.
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Structure-activity of valencenoid derivatives and their repellence to the Formosan subterranean termite.
Journal of chemical ecology, 2003Co-Authors: Betty C. R. Zhu, Gregg Henderson, Anne M. Sauer, William E. Crowe, Roger A. LaineAbstract:Eight valencenoid derivatives were evaluated for their repelling activity against Formosan subterranean termites, Coptotermes formosanus Shiraki. Among them, 1,10-dihydroNootkatone was the strongest repellent, and valencene was the weakest. Results of the structure–repellency relationships indicated (1) reduction of the ketone group to the alcohol on position 2 of Nootkatone curtailed the activity; (2) because of the low activity of valencene relative to Nootkatone that the ketone group was essential for repellent activity; (3) reduction of the 1,10 double bond (1,10-dihydroNootkatone and tetrahydroNootkatone) produced compounds more repellent than Nootkatone; (4) the isopropenyl group probably does not participate in binding as evidenced by no significant difference in the repellent activity among Nootkatone (double bond between position 11 and 12), isoNootkatone (double bond between position 7 and 11), and 11,12-dihydroNootkatone.
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Nootkatone Is a Repellent for Formosan Subterranean Termite (Coptotermes formosanus)
Journal of Chemical Ecology, 2001Co-Authors: Betty C. R. Zhu, Gregg Henderson, Lara Maistrello, Feng Chen, Roger A. LaineAbstract:We examined the behavior of Formosan subterranean termites toward one of the components of vetiver grass oil, the roots of which manufacture insect repellents. We found Nootkatone, a sesquiterpene ketone, isolated from vetiver oil is a strong repellent and toxicant to Formosan subterranean termites. The lowest effective concentration tested was 10 μg/g substrate. This is the first report of Nootkatone being a repellent to insects.
Xiaoyan Guo - One of the best experts on this subject based on the ideXlab platform.
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heterologous biosynthesis of Nootkatone in unconventional yeast yarrowia lipolytica
Biochemical Engineering Journal, 2018Co-Authors: Xiaoyan Guo, Jie SunAbstract:Abstract Yarrowia lipolytica is an unconventional yeast that is regarded as safe. It is the potential platform for terpenoids production because it possesses the endogenous MVA pathway which can provide precursors for terpenoids synthesis. Herein, we constructed (+)-Nootkatone, a sesquiterpenoid which is highly demanded in cosmetics and fragrance industries, synthetic pathway in Yarrowia lipolytica ATCC 201249. Heterologous production of (+)-Nootkatone was achieved by co-expressing (+)-valencene synthase CnVS, codon-optimized (+)-Nootkatone synthase opCYP706M1 and codon-optimized NADPH-cytochrome P450 reductase opAtCPR1. The initial (+)-Nootkatone production was 45.6 μg/L. Fusion of opCYP706M1 and opt46AtCPR1 (opAtCPR1 with 46 amino acids truncated at N-terminal) increased (+)-valencene conversion efficiency to (+)-Nootkatone and (+)-Nootkatone production increased to 312.2 μg/L, nearly six times higher than the initial. Overexpression of the MVA pathway rate limiting enzymes 3-hydroxy-3-methylglutaryl-coenzyme A reductase tHMG1 and FPP synthase ERG20 improved the (+)-Nootkatone production furtherly. The final engineered strain achieved a (+)-Nootkatone titer of 978.2 μg/L, which was a 20.5-fold increase compared to those simply coexpressed CnVS, opCYP706M1 and opAtCPR1. This is the first report of heterologous biosynthesis of (+)-Nootkatone in Y. lipolytica, which will provide a favorable reference for studies on heterologous production of other sesquiterpenoids and high-efficiency expression of P450 enzymes in Y. lipolytica.
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Heterologous biosynthesis of (+)-Nootkatone in unconventional yeast Yarrowia lipolytica
Biochemical Engineering Journal, 2018Co-Authors: Xiaoyan Guo, Jie SunAbstract:Abstract Yarrowia lipolytica is an unconventional yeast that is regarded as safe. It is the potential platform for terpenoids production because it possesses the endogenous MVA pathway which can provide precursors for terpenoids synthesis. Herein, we constructed (+)-Nootkatone, a sesquiterpenoid which is highly demanded in cosmetics and fragrance industries, synthetic pathway in Yarrowia lipolytica ATCC 201249. Heterologous production of (+)-Nootkatone was achieved by co-expressing (+)-valencene synthase CnVS, codon-optimized (+)-Nootkatone synthase opCYP706M1 and codon-optimized NADPH-cytochrome P450 reductase opAtCPR1. The initial (+)-Nootkatone production was 45.6 μg/L. Fusion of opCYP706M1 and opt46AtCPR1 (opAtCPR1 with 46 amino acids truncated at N-terminal) increased (+)-valencene conversion efficiency to (+)-Nootkatone and (+)-Nootkatone production increased to 312.2 μg/L, nearly six times higher than the initial. Overexpression of the MVA pathway rate limiting enzymes 3-hydroxy-3-methylglutaryl-coenzyme A reductase tHMG1 and FPP synthase ERG20 improved the (+)-Nootkatone production furtherly. The final engineered strain achieved a (+)-Nootkatone titer of 978.2 μg/L, which was a 20.5-fold increase compared to those simply coexpressed CnVS, opCYP706M1 and opAtCPR1. This is the first report of heterologous biosynthesis of (+)-Nootkatone in Y. lipolytica, which will provide a favorable reference for studies on heterologous production of other sesquiterpenoids and high-efficiency expression of P450 enzymes in Y. lipolytica.
