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WANG HuiLing WANG XiaoYue YAN AiLing SUN Lei ZHANG GuoJun REN JianCheng XU HaiYing 《中国农业科学》2019,52(7):1136-1149
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《Scandinavian Journal of Forest Research》2012,27(1-4):535-539
We compared the degree of browsing by moose on 30 clones of Scots pine with the concentrations of mono‐ and diterpenes in their needles. The pine clones originated from 11 Swedish and one Norwegian locality within the latitudes 61–69° N. They were grown in a nursery in northern Sweden, close to 63° N, and were accidently exposed to moose during one winter. The relative amount of twig biomass removed differed significantly between clones. No statistically significant correlation was found between monoterpene concentrations in the needles and degree of moose browsing. For the diterpene pinifolic acid, however, there was a significant negative correlation. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):25-36
The terpenic profile for 8 major monoterpenes determined on ten grafted clones of Scots pine grown on three different sites in Sweden. As graft effects could not be detected, oleoresin, samples from primary and secondary grafts were used to study genetic variation. In three quite different environmental conditions, a strong broad sense heritability was demonstrated for 3‐carene, myrcene, limonene and β‐phellandrene. Pinenes and sabinene seem to be much more dependent on environmental factors. Both site and clone × site interaction have a small effect on overall phenotypic variation. There is a strong positive correlation between concentrations of 3‐carene and terpinolene, which supports a possible pleiotropic effect of the same major gene on the two monoterpenes. The results show that there is no risk of an important bias when the comparison is made between genotypes sampled on very different sites (stands or comparative trials). The relative concentration of monoterpenes is to a great extent independent of environmental conditions. 相似文献
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There has been a tremendous increase in the rate of new terpenoids from marine-derived fungi being discovered, while new monoterpenes were rarely isolated from marine-derived fungi in the past two decades. Three new monoterpenes, diaporterpenes A–C (1–3), and one new α-pyrones, diaporpyrone A (6), along with nine known polyketides 4, 5, and 7–13 were isolated from the ascidian-derived fungus Diaporthe sp. SYSU-MS4722. Their planar structures were elucidated based on extensive spectroscopic analyses (1D and 2D NMR and HR-ESIMS). The absolute configurations of 1 and 3 were identified by an X-ray crystallographic diffraction experiment using Cu-Ka radiation, and those of compound 2 were assigned by calculating NMR chemical shifts and ECD spectra. It afforded an example of natural epimers with different physical properties, especially crystallization, due to the difference in intermolecular hydrogen bonding. Compounds 9, 10, and 13 showed moderate total antioxidant capacity (0.82 of 9; 0.70 of 10; 0.48 of 13) with Trolox (total antioxidant capacity: 1.0) as a positive control, and compounds 5 and 7 showed anti-inflammatory activity with IC50 values of 35.4 and 40.8 µM, respectively (positive control indomethacin: IC50 = 35.8 µM). 相似文献
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夏季油松及侧柏单萜烯变化规律及二次有机气溶胶生成潜势的估算 总被引:1,自引:0,他引:1
利用动态顶空采集法、热脱附—气相色谱质谱联用仪以及外标法,以油松、侧柏挥发的单萜烯为基础,分析其日变化规律及与环境因素的相关性,同时利用气溶胶生成系数估算单萜烯二次有机气溶胶。结果表明:α-蒎烯、柠檬烯是油松挥发最多的2种萜烯物质,其平均含量为15.61%,11.77%;侧柏挥发最多的也是这2种,其平均含量为17.49%,15.34%。油松、侧柏均挥发的α-蒎烯、β-月桂烯、柠檬烯呈先升高后降低的单峰变化,且均在13:00—14:00出现最高峰。β-蒎烯呈先降低后升高的变化,松油烯变化较为平稳,维持在1.20%左右。单萜烯的挥发受环境因素的影响,高温、低相对湿度在一定程度上促进了单萜烯的释放,而温度是主要影响因素,单萜烯的释放与光合有效辐射无关。单萜烯对二次有机气溶胶有一定的生成潜势,生成的SOA浓度与释放的VOCs浓度呈正相关,且各时间段内油松、侧柏单萜烯SOA浓度均显著高于林外大气单萜烯SOA浓度。 相似文献