Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-san...Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.展开更多
Tropical medicinal plant spices have remained underutilized in commercial food processing because of the inadequate chemical characterization of their terpene compositions. The activity of medicinal plants used in fla...Tropical medicinal plant spices have remained underutilized in commercial food processing because of the inadequate chemical characterization of their terpene compositions. The activity of medicinal plants used in flavoring is due to their terpene contents. Terpene contents of Aframomum danielli seeds, Xylopia aethiopica fruits, Syzygium aromaticum leaves, Piper guineense seeds, and Monodora myristica seeds were determined using headspace solid-phase microextraction combined with gas chromatography-mass spectrometry. P. guineense is rich in terpinene and terpinolene (2.5 g per 100 g), S. aromaticum has caryophyllene (0.68 g per 100 g);A. danielli is rich in ocimene (1.65 g per 100 g);X. aethiopica is rich in ocimene (2.94 g per 100 g);M. mystristica is rich in delta carene (0.49 g per 100 g). Combinations of the five medicinal plant spices are being applied as flavorings in packaged tropical food.展开更多
Efficacy of five plant molecules against thirty three clinical isolates and two standard strains of C. albicans, differentially susceptible to fluconazole (FLC) is tested in this study. Effect on biofilm (adhesion, de...Efficacy of five plant molecules against thirty three clinical isolates and two standard strains of C. albicans, differentially susceptible to fluconazole (FLC) is tested in this study. Effect on biofilm (adhesion, development and maturation) formation, morphogenesis and synergy with fluconazole (FLC) against a FLC resistant strain of Candida albicans ATCC 10231 is also evaluated. All the plant molecules tested were equally effective against isolates and strains of C. albicans (N = 35) tested in this study. Cinnamaldehyde was found most effective against planktonic growth followed by ocimene. Both the molecules exhibited fungicidal activity and killed 99.9% of inoculum within 80 and 20 min of exposure respectively at 0.62 mM and 176.8 mM concentrations. Curcumin (5 - 20 mM), camphene (8 - 32 mM) and farnesene (25 - 100 mM), although inhibited planktonic growth, were fungistatic. All the five plant molecules tested in this study inhibited morphogenesis significantly and exhibited considerable activity against biofilm formation. Inhibition of biofilm was found to be stage specific i.e. efficacy was more against adhesion followed by developing and mature biofilm. Plant molecules tested exhibited excellent synergy with fluconazole. However FIC index values 0.155, 0.062 and 0.046 indicate that ocimene was the most effective synergistic molecule inhibited planktonic growth, developing biofilm and mature biofilm growth respectively at very low concentrations. This is the first report of anti-Candida activity of three terpenoids viz. ocimene, farnesene and camphene against planktonic & biofilm growth, morphogenesis as well as synergy with FLC. Plant molecules tested in this study may find use in antifungal chemotherapy individually and or in a combination with FLC.展开更多
The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However,...The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However, no safe and effective methods have been found to protect sweet potato from this pest. Herbivore-induced plant volatiles(HIPVs)promote various defensive bioactivities, but their formation and the defense mechanisms in sweet potato have not been investigated. To identify the defensive HIPVs in sweet potato, the release dynamics of volatiles was monitored.The biosynthetic pathways and regulatory factors of the candidate HIPVs were revealed via stable isotope tracing and analyses at the transcriptional and metabolic levels. Finally, the anti-insect activities and the defense mechanisms of the gaseous candidates were evaluated. The production of(Z)-3-hexenyl acetate(z3HAC) and allo-ocimene was induced by sweet potato weevil feeding, with a distinct circadian rhythm. Ipomoea batatas ocimene synthase(IbOS) is first reported here as a key gene in allo-ocimene synthesis. Insect-induced wounding promoted the production of the substrate,(Z)-3-hexenol, and upregulated the expression of IbOS, which resulted in higher contents of z3HAC and allo-ocimene,respectively. Gaseous z3HAC and allo-ocimene primed nearby plants to defend themselves against sweet potato weevils. These results provide important data regarding the formation, regulation, and signal transduction mechanisms of defensive volatiles in sweet potato, with potential implications for improving sweet potato weevil management strategies.展开更多
Evaluation of thirty one core collections of Ocimum sanctum L. synonyms O. tenuiflorum L. collected from different ecological regions representing contrasting environment of India was carried out. All the collections ...Evaluation of thirty one core collections of Ocimum sanctum L. synonyms O. tenuiflorum L. collected from different ecological regions representing contrasting environment of India was carried out. All the collections were grown under sub-tropical region of Jammu, India. Study revealed wide range of variability in quantitive and qualitative attributes of oil. Essential oil content ranged between 0.16% ± 0.01% - 0.55% ± 0.08% showing the presence of fifteen constituents. Methyl eugenol (1.54% - 93.16%) and Eugenol (0.06% - 70.41%), were the major constituent. The other major constituent of the oil was β-Caryophyllene (4.60% - 33.77%) which was detected in almost all the collections. Borneol, Copane, α Caryophyllene were other constituents detected in almost all the accessions. α selinene was detected in traces in only three accessions (OS-01, OS-03, OS-50) and β-selinene was detected in four accessions (OS-01, OS-03, OS-50, OS-72. Accession OS-70 collected from Patna, showed distinct chemical profile having β-Elemene (32.81%), β-Cary- ophyllene (16.37%), Germacrene-D (18.05%), β-Ocimene (17.69%) and Copane (5.738%). Being distinct in oil profiling, Patna collection was designated as distinct chemotype. Collections OS-50 from Gwalior from Central India and OS-59 from Rajkot Western India have been identified as methyl eugenol (93.16%) and eugenol (70.41%) rich geno- types. The data collected provided useful information with respect to composition of essential oil among core collection evaluated representing various agro-climatic zones.展开更多
植物通讯信号分子β-罗勒烯在植物防御方面起着重要作用,受β-罗勒烯诱导快速高表达的SFIBO(snoRNAs Fast-Induced by Ocimene)基因的启动子特性有待研究。SFIBO基因起始密码子上游有877 bp,依据这段序列上已知的元件分布特征,将877 bp...植物通讯信号分子β-罗勒烯在植物防御方面起着重要作用,受β-罗勒烯诱导快速高表达的SFIBO(snoRNAs Fast-Induced by Ocimene)基因的启动子特性有待研究。SFIBO基因起始密码子上游有877 bp,依据这段序列上已知的元件分布特征,将877 bp分成三段:-877~-1 bp、-637~-1 bp和-277~-1 bp。将这3个片段分别扩增后与GUS报告基因构建融合表达框,并利用浸花法将这3个植物双元表达载体转化拟南芥Col-0。对GUS组织化学染色进行分析,结果显示SFIBO基因的有效启动子为起始密码子上游637 bp DNA片段,β-罗勒烯诱导反应的顺式作用元件在-637~-277 bp之间的这360 bp DNA序列上。以上结果为下一步确定β-罗勒烯响应元件的具体序列和研究SFIBO基因的功能提供了科学依据。展开更多
基金financially supported by the open research fund program of Science and Technology on Aerospace Chemical Power Laboratory (No. STACPL120221B03)the National Natural Science Foundation of China (Nos. s22175059,52073275 and U21A20279)。
文摘Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.
文摘Tropical medicinal plant spices have remained underutilized in commercial food processing because of the inadequate chemical characterization of their terpene compositions. The activity of medicinal plants used in flavoring is due to their terpene contents. Terpene contents of Aframomum danielli seeds, Xylopia aethiopica fruits, Syzygium aromaticum leaves, Piper guineense seeds, and Monodora myristica seeds were determined using headspace solid-phase microextraction combined with gas chromatography-mass spectrometry. P. guineense is rich in terpinene and terpinolene (2.5 g per 100 g), S. aromaticum has caryophyllene (0.68 g per 100 g);A. danielli is rich in ocimene (1.65 g per 100 g);X. aethiopica is rich in ocimene (2.94 g per 100 g);M. mystristica is rich in delta carene (0.49 g per 100 g). Combinations of the five medicinal plant spices are being applied as flavorings in packaged tropical food.
文摘Efficacy of five plant molecules against thirty three clinical isolates and two standard strains of C. albicans, differentially susceptible to fluconazole (FLC) is tested in this study. Effect on biofilm (adhesion, development and maturation) formation, morphogenesis and synergy with fluconazole (FLC) against a FLC resistant strain of Candida albicans ATCC 10231 is also evaluated. All the plant molecules tested were equally effective against isolates and strains of C. albicans (N = 35) tested in this study. Cinnamaldehyde was found most effective against planktonic growth followed by ocimene. Both the molecules exhibited fungicidal activity and killed 99.9% of inoculum within 80 and 20 min of exposure respectively at 0.62 mM and 176.8 mM concentrations. Curcumin (5 - 20 mM), camphene (8 - 32 mM) and farnesene (25 - 100 mM), although inhibited planktonic growth, were fungistatic. All the five plant molecules tested in this study inhibited morphogenesis significantly and exhibited considerable activity against biofilm formation. Inhibition of biofilm was found to be stage specific i.e. efficacy was more against adhesion followed by developing and mature biofilm. Plant molecules tested exhibited excellent synergy with fluconazole. However FIC index values 0.155, 0.062 and 0.046 indicate that ocimene was the most effective synergistic molecule inhibited planktonic growth, developing biofilm and mature biofilm growth respectively at very low concentrations. This is the first report of anti-Candida activity of three terpenoids viz. ocimene, farnesene and camphene against planktonic & biofilm growth, morphogenesis as well as synergy with FLC. Plant molecules tested in this study may find use in antifungal chemotherapy individually and or in a combination with FLC.
基金supported by the National Natural Science Foundation of China–Guangdong Natural Science Foundation Joint Project (U1701234)。
文摘The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However, no safe and effective methods have been found to protect sweet potato from this pest. Herbivore-induced plant volatiles(HIPVs)promote various defensive bioactivities, but their formation and the defense mechanisms in sweet potato have not been investigated. To identify the defensive HIPVs in sweet potato, the release dynamics of volatiles was monitored.The biosynthetic pathways and regulatory factors of the candidate HIPVs were revealed via stable isotope tracing and analyses at the transcriptional and metabolic levels. Finally, the anti-insect activities and the defense mechanisms of the gaseous candidates were evaluated. The production of(Z)-3-hexenyl acetate(z3HAC) and allo-ocimene was induced by sweet potato weevil feeding, with a distinct circadian rhythm. Ipomoea batatas ocimene synthase(IbOS) is first reported here as a key gene in allo-ocimene synthesis. Insect-induced wounding promoted the production of the substrate,(Z)-3-hexenol, and upregulated the expression of IbOS, which resulted in higher contents of z3HAC and allo-ocimene,respectively. Gaseous z3HAC and allo-ocimene primed nearby plants to defend themselves against sweet potato weevils. These results provide important data regarding the formation, regulation, and signal transduction mechanisms of defensive volatiles in sweet potato, with potential implications for improving sweet potato weevil management strategies.
文摘Evaluation of thirty one core collections of Ocimum sanctum L. synonyms O. tenuiflorum L. collected from different ecological regions representing contrasting environment of India was carried out. All the collections were grown under sub-tropical region of Jammu, India. Study revealed wide range of variability in quantitive and qualitative attributes of oil. Essential oil content ranged between 0.16% ± 0.01% - 0.55% ± 0.08% showing the presence of fifteen constituents. Methyl eugenol (1.54% - 93.16%) and Eugenol (0.06% - 70.41%), were the major constituent. The other major constituent of the oil was β-Caryophyllene (4.60% - 33.77%) which was detected in almost all the collections. Borneol, Copane, α Caryophyllene were other constituents detected in almost all the accessions. α selinene was detected in traces in only three accessions (OS-01, OS-03, OS-50) and β-selinene was detected in four accessions (OS-01, OS-03, OS-50, OS-72. Accession OS-70 collected from Patna, showed distinct chemical profile having β-Elemene (32.81%), β-Cary- ophyllene (16.37%), Germacrene-D (18.05%), β-Ocimene (17.69%) and Copane (5.738%). Being distinct in oil profiling, Patna collection was designated as distinct chemotype. Collections OS-50 from Gwalior from Central India and OS-59 from Rajkot Western India have been identified as methyl eugenol (93.16%) and eugenol (70.41%) rich geno- types. The data collected provided useful information with respect to composition of essential oil among core collection evaluated representing various agro-climatic zones.
文摘植物通讯信号分子β-罗勒烯在植物防御方面起着重要作用,受β-罗勒烯诱导快速高表达的SFIBO(snoRNAs Fast-Induced by Ocimene)基因的启动子特性有待研究。SFIBO基因起始密码子上游有877 bp,依据这段序列上已知的元件分布特征,将877 bp分成三段:-877~-1 bp、-637~-1 bp和-277~-1 bp。将这3个片段分别扩增后与GUS报告基因构建融合表达框,并利用浸花法将这3个植物双元表达载体转化拟南芥Col-0。对GUS组织化学染色进行分析,结果显示SFIBO基因的有效启动子为起始密码子上游637 bp DNA片段,β-罗勒烯诱导反应的顺式作用元件在-637~-277 bp之间的这360 bp DNA序列上。以上结果为下一步确定β-罗勒烯响应元件的具体序列和研究SFIBO基因的功能提供了科学依据。
