枫香叶采后挥发物表征及影响因子研究

以枫香(Liquidambar formosana)叶为材料,采用气相色谱/质谱(GC/MS)联用技术对不同发育程度、干燥时间、储存方式及萃取温度下枫香叶挥发性成分进行分析,以揭示枫香叶释放挥发性有机化合物数量及不同采后处理下挥发物的消长规律。结果表明：(1)枫香叶释放的萜烯类化合物以α-蒎烯、β-蒎烯、β-水芹烯、柠檬烯为主;(2)嫩叶挥发性成分种类较成熟叶高,莰烯、β-萜品烯、罗勒烯仅存在于嫩叶,3-蒈烯、γ-松油烯仅存在于成熟叶;(3)干燥时间对枫香叶挥发性化合物影响较大,挥发物种类随干燥时间延长呈逐渐下降趋势,但主要的萜烯类化合物在不同干燥时间内均能被检测到,表现相对稳定;(4) –5 ℃及17 ℃储存可保留更多挥发性化合物,室温保存则失去较多化合物,但主要的萜烯类化合物在不同储存方式下均可被检测到;(5) 90 ℃高温萃取可获得更多的挥发性化合物,但70 ℃萃取得到的萜烯类化合物相对含量较高,室温萃取所得化合物种类虽最少,但更能反映园林应用中枫香叶芳香物质挥发的实际情况。研究结果可为枫香叶的采后处理及高值化资源利用提供参考。     

Phenolic compounds in apple leaves after infection with apple scab

Leaves of the scab-susceptible apple (Malus domestica) cultivar Golden Delicious were harvested from May to August 2008 and 2009. Some leaves were healthy and some infected with fungus Venturia inaequalis. The phenolic compounds were analysed in healthy leaves, infected leaves and in the scab spot tissue. In comparison to healthy leaves, the infected leaves showed higher contents of hydroxycinnamic acid, flavanols and phloridzin, while lower contents on procyanidins, quercetins and phloretin. The total amount of phenolic compounds in the infected tissue was 10 to 20 % higher than in the healthy leaves. Accumulation of phenolic compounds is a post-infection response, and probably their further transformation is a prerequisite for plant resistance.     

A comparison of the volatile oils of mature versus young leaves of Juniperus scopulorum: Chemosystematic significance

The volatile oils of leaves of clonal, greenhouse grown trees of J. scopulorum cv. platinum were examined from young (juvenile or whip leaves) and mature (adult or scale leaves) foliage. Of 36 compounds subjected to analysis of variance, 19 showed significant differences between young and old leaves. In general, the hydrocarbon terpenoids were higher in concentration in new leaves while the oxygenated compounds were higher in the older leaves. This same pattern has been reported in several other gymnosperms. Numerical taxonomy using data on the volatile oils from young and mature leaves yielded the same relative similarities among the five trees examined. Surprisingly, the plants were more similar in the volatile oil from the young leaves than from the mature leaves. The mixing of different ages of leaves in samples for chemosystematic studies is, however, to be discouraged     

刺五加和短梗五加叶片初生代谢的发育特异性调控研究

利用GC-MS技术对刺五加（Acanthopanax senticosus（Rupr. et Maxim.） Harms）和短梗五加（Acanthopanax sessiliflorus（Rupr. et Maxim.） Seem）叶片初级代谢产物进行了代谢组学分析,运用PCA和OPLS-DA方法分析后,将刺五加和短梗五加叶片划分为3个发育时期：生长期（Growth period）、旺盛期（Exuberant period）、凋落期（Autumn period）。刺五加叶片3个时期筛选出糖类、氨基酸、有机酸、脂肪酸、多元醇等共53个差异化合物,短梗五加叶片3个时期筛选出糖类、氨基酸、有机酸、脂肪酸、多元醇等共51个差异化合物。进一步分析表明,刺五加和短梗五加叶片在旺盛期和凋落期之间差异化合物最多,其中刺五加主要是糖类、有机酸;短梗五加则除了上述两类化合物外,还包括脂肪酸、多胺类化合物。两者作为同属植物,在差异化合物的组成类型方面具有较高的相似性。结果初步揭示了2种同属药用植物叶片不同时期初级代谢物的积累模式,为2种植物叶片利用提供理论基础。     

Diversity of phenolic compounds and plant traits in coexisting Patagonian desert shrub species of Argentina

Desert shrubs often accumulate different types of phenolic compounds but what determines the amount and diversity of these compounds is an issue scarcely explored. The aim of this study was to assess differences in the amount and diversity of phenolic compounds in leaves among coexisting shrub species differing in rooting depth and leaf turnover. We hypothesized that the diversity and amount of phenolic compounds in leaves of desert shrubs are related to access to soil water through rooting depth, and to leaf turnover. The study was carried out in the Patagonian Monte of Argentina. We collected green leaves of six species representing the dominant shrub morphotypes (tall evergreen, tall deciduous, and medium evergreen shrubs) and assessed lignin concentration and groups of soluble phenols obtained by sequential extraction with ethyl ether, ethyl acetate, and amyl alcohol. We also assessed nitrogen concentration in leaves and leaf mass per unit area (LMA) as traits related to leaf lifespan. The diversity of phenolic compounds was higher in green leaves of tall shrubs with deep rooting depth than in those of medium evergreen shrubs with shallow rooting depth. Diversity of phenolic compounds in green leaves was negatively related to lignin concentration. Evergreen shrubs had higher amount of phenolic compounds in green leaves than deciduous ones and the total amount of phenolic compounds in green leaves was positively related to LMA. We concluded that access to soil water sources and leaf turnover were related to the amount and diversity of phenolic compounds in green leaves of desert shrub species and these results are consistent with those predicted by the resource availability theory for plants from resource-rich and resource-poor habitats.     

顶空固相微萃取/气相色谱/质谱法分析贵州产海金沙挥发性成分

采用顶空固相微萃取和气质联用技术(HS-SPME-GC-MS),首次分析了贵州产海金沙根和叶的挥发性成分。从根中鉴定33了种组分,从叶中鉴定了51种组分。其中有18种组分二者是相同的。海金沙根中的烷烃在植物生长的过程中被酶催化转变为多种挥发性化学成分。     

Characterisation of the effects of leaf galls of Clusiamyia nitida (Cecidomyiidae) on Clusia lanceolata Cambess. (Clusiaceae): Anatomical aspects and chemical analysis of essential oil

Galls develop in different plant organs and are induced by the activity of various organisms. Some studies have investigated the ecological interactions between species of Clusia and gall-inducing insects. The goal of our study is to characterise changes in leaf anatomy caused by the activity of gall insects in Clusia lanceolata. Additionally, we also investigated the chemical composition of volatile compounds of normal leaves and those with galls to detect possible effects on the host plants. For anatomical studies, we used botanical material fixed in FAA₅₀. Transversal sections of the leaf blade were obtained from samples of leaves located on the third and fourth nodes from both male and female individuals. Material was studied from both sexes both with unaffected leaves and leaves containing galls. Fresh leaves of C. lanceolata were used for the extraction of volatile compounds, which were submitted to stem distillation using a modified Clevenger apparatus determining the oil yields subsequently (w/w). The unaffected leaves of female and male individuals of C. lanceolata exhibit similar anatomical structures. However, galls on leaves of both sexes show anatomical differences. The activity of the gall insect Clusiamyia nitida induces several changes in the foliar anatomy and the distribution of metabolic compounds in new tissues during gall development. However, the larvae are not able to induce significant changes in the volatile compounds of inflected leaves from male and female individuals.     

Comparative Distribution and Metabolism of Xylem-Borne Amino Compounds and Sucrose in Shoots of Populus deltoides

The transport and metabolism of xylem-borne amino compounds and sucrose were investigated in rapidly growing shoots of cottonwood (Populus deltoides Bartr. ex Marsh.). ¹⁴C-labeled glutamine, threonine, alanine, glutamic acid, aspartic acid, and sucrose were applied to the base of severed stems for transport in xylem. Distribution and metabolism of the compounds were followed with autoradiography, microautoradiography, and radioassay. Three utilization patterns were observed: (a) little alanine and sucrose was transported to the laminae of either mature leaves or developing leaves. These compounds were taken up from xylem free-space and utilized in adjacent tissue; (b) threonine also did not move into mature leaves but was translocated to developing leaves or utilized in the stem; (c) glutamic acid and aspartic acid were transported directly into the laminae of mature leaves via the xylem. Relatively less ¹⁴C was retained in stems compared to the other compounds.

Metabolism of the test compounds also differed considerably. ¹⁴C from amino acids moved primarily into organic acids and protein. The ¹⁴C from sucrose was widely distributed among the chemical fractions, with a high percentage found in structural carbohydrates. Clearly, cottonwood stems contain efficient uptake and transfer systems that differentiate among various compounds moving from root to shoot in xylem.

     

蒲葵叶化学成分研究

为研究传统药用植物蒲葵的化学成分,从蒲葵叶中分离得到5个化合物,分别鉴定为:3,5,7-三羟基-4′甲氧基黄酮醇(Ⅰ)、5,7,4′-三羟基黄酮-8-C-D-葡萄糖苷(Ⅱ)、β-谷甾醇(Ⅲ)、豆甾醇(Ⅳ)、二十六烷醇(Ⅴ)。该5个已知化合物均为首次从蒲葵叶中分离得到。     

石山巴豆与毛果巴豆叶中挥发油成分分析

采用水蒸气蒸馏法提取石山巴豆和毛果巴豆叶中的挥发油,利用GC-MS联用仪对其化学成分进行分析和鉴定,以归一化法计算各个化学成分的相对含量。结果表明:从石山巴豆叶鉴定出39种化合物,占总量的95.96%,主要成分是α-松油醇(17.57%)、桉树醇(11.13%)、乙酸松油酯(9.07%)、倍半水芹烯(8.52%)等;从毛果巴豆叶鉴定出55种化合物,占总量的97.8%,以反式-橙花叔醇(9.48%)、α-松油醇(7.51%)、桉树醇(6.43%)、乙酸松油酯(6.72%)为主要成分。两种植物叶中的挥发油成分均以萜醇、倍半萜烯为主,并且其中多种成分具有生物活性,因此研究结果可为石山巴豆和毛果巴豆的开发利用提供科学依据。     

Studies on the Polyphenolic Composition and the Antioxidant Properties of the Leaves of Poplar (Populus spp.) Various Species and Hybrids

The chemical composition in terms of flavonoid and salicylic compounds of leaves from 6 species and 3 hybrids of poplars (Populus) was identified with the use of TLC and HPLC-DAD/ESI-MS methods. Chromatographic analyses were carried out with 21 standard compounds including salicylic compounds (2), phenolic acids (3) and flavonoids (16). Moreover, on the basis of the obtained chromatographic data from the HPLC-DAD/ESI-MS and TLC separations, the presence of salicortin, tremulacin and chlorogenic acid was confirmed, depending on the analyzed poplar species or hybrid. The content of salicylic compounds was determined by HPLC-UV method and expressed on salicin as free and total fraction. Total flavonoid content was determined by spectroscopic method as quercetin equivalent. Significant qualitative and quantitative differences in the chemical composition of the analyzed leaves were demonstrated. The highest concentration of flavonoids (8.02 mg/g) was found in the leaves of Populus nigra, while the highest content of salicylic compounds (47.14 mg/g) was found in the leaves of P.×berolinensis. The antioxidant and xanthine oxidase inhibition properties of extracts from poplar leaves were investigated by TLC bioautography. It has been shown that the richest set of compounds with antioxidant properties are present in the leaves of P. alba, P.×candicans and P. nigra.     

施硅提高水稻叶片对紫外线胁迫的抗性

采用加硅与缺硅营养液培养的方法, 首次研究证明硅能提高水稻(Oryza sativa L.)叶片抗紫外线胁迫的能力。结果表明, 在紫外胁迫条件下,缺硅水稻叶片表面出现明显的棕色伤害斑点,而加硅叶片未出现伤害症状。硅在水稻表皮细胞壁及细胞内部的积累明显促进了紫外吸收物质在表皮细胞中的聚集,使表皮中可溶性酚类物质含量提高17%,不溶性紫外吸收物质的含量增加65%左右。荧光显微镜观察表明,在表皮细胞外壁或胞内沉积的水合二氧化硅固体中包含着大量不溶性的酚类化合物,它们与可溶性酚类物质一起在叶片的上、下表皮细胞中形成了吸收紫外线的屏障。     

Cytokinins in the leaves of Ginkgo biloba. II. Metabolism and transport of 8 (14C) zeatin applied to shoot explants

Irrespective of their age, leaves of Ginkgo biloba metabolised applied 8 (¹⁴C) zeatin to compounds of similar chromatographic properties. Glucosylation is apparently not a normal feature of cytokinin metabolism in immature leaves. However, the application of zeatin to these leaves did result in the formation of metabolites which co-chromatographed with glucosylated cytokinins. As far as cytokinin metabolism is concerned therefore, this application of excess zeatin allowed immature leaves to behave as mature or senescing leaves. Overall metabolism was fastest in immature leaves. From the metabolites formed it would appear as if oxidation, which resulted in the formation of a metabolite which co-eluted with N-(purin-6-yl)glycine, was also important in immature leaves. In senescing leaves glucosylation was the major form of metabolism. Extraction and re-application of the polar metabolites (formed from zeatin) to mature leaves resulted in the formation of compounds which co-chromatographed with zeatin. This suggests that these compounds could serve as precursors for zeatin or could be hydrolysed to form zeatin.Very little of the applied radioactivity was exported from the leaves irrespective of their physiological age. When the metabolites, obtained after zeatin application to mature leaves, were extracted and reapplied to the leaves, export of radioactive material was much improved. The results suggest that should cytokinins such as zeatin be translocated to mature leaves of this deciduous gymnosperm their export from the leaves would be unlikely unless first metabolised. In all probability the metabolites concerned are cytokinin glucosides.The financial support of the C.S.I.R., Pretoria, is gratefully acknowledged.     

Seasonal Changes in the Cytokinin Content of the Leaves of Salix babylonica

The young and old leaves of Salix babylonica contain at least four cell division-inducing compounds which coeluted with zeatin, zeatin riboside and their glucosylated derivatives. During the course of the growing season quantitative changes in the cytokinin content of the leaves were observed. The cytokinin glucosides increased as the leaves aged. The compounds which co-chromatographed with zeatin and zeatin riboside initially increased until early autumn and then decreased as the leaves senesced. It appears as though the cytokinins transported from the roots are metabolized in the leaves and are converted to their glucosides. Although it has been reported in the literature that Salix root exudate contains very small amounts of cytokinin in late summer and autumn, these compounds increase in the leaves for most of the growing season, suggesting that the leaves may not only obtain cytokinins from the roots but may well be an active site of cytokinin synthesis. It is, however, possible that cytokinins are also transported to the leaves via the phloem, thus accounting for their accumulation in these organs.     

Release of Antifungal Phenolic Compounds from Cucumber Mosaic Virus-Infected and Noninfected Cowpea Protoplasts

Fungitoxic phenolic compounds were released from cucumber mosaic virus (CMV)-infected and noninfected cowpea protoplasts. These compounds were presumed by thin layer chromatography as similar compounds released into the leaf ambient fluids when CMV-infected cowpea leaves were incubated in water. Larger amounts of the compounds were released from CMV-infected cowpea protoplasts than from noninfected protoplasts.     

施硅提高水稻叶片对紫外线胁迫的抗性

采用加硅与缺硅营养液培养的方法,首次研究证明硅能提高水稻(Oryza sativa L.)叶片抗紫外线胁迫的能力.结果表明,在紫外胁迫条件下,缺硅水稻叶片表面出现明显的棕色伤害斑点,而加硅叶片未出现伤害症状.硅在水稻表皮细胞壁及细胞内部的积累明显促进了紫外吸收物质在表皮细胞中的聚集,使表皮中可溶性酚类物质含量提高17%,不溶性紫外吸收物质的含量增加65%左右.荧光显微镜观察表明,在表皮细胞外壁或胞内沉积的水合二氧化硅固体中包含着大量不溶性的酚类化合物,它们与可溶性酚类物质一起在叶片的上、下表皮细胞中形成了吸收紫外线的屏障.     

唐古拉特白刺和西伯利亚白刺叶挥发性成分研究

利用固相微萃取技术提取唐古拉特白刺和西伯利亚白刺叶的挥发性成分,采用气相色谱-质谱联用结合保留指数法鉴定了其成分。分别从唐古拉特白刺叶和西伯利亚白刺叶中的挥发油中鉴定出40、33个化合物,二者共有成分27个。对比二者的挥发性成分,发现唐古拉特白刺叶烃类化合物(25.54%),远高于西伯利亚白刺叶(12.00%),并且以二十一烷为转折点,在此之前,各烃类化合物的在唐古拉特白刺叶中的含量均高于西伯利亚白刺叶,在此之后,烃类化合物在前者中的含量低于后者;乙酸仅存在于西伯利亚白刺叶中,且含量高达20.00%,二氢猕猴桃内酯为二者叶中的主要赋香成分。     

HPLC同时测定大叶冬青叶中10种多酚成分的含量及抗氧化活性研究

建立HPLC同时测定大叶冬青叶中新绿原酸、绿原酸、隐绿原酸、咖啡酸、对羟基肉桂酸、芦丁、异槲皮苷、异绿原酸B、异绿原酸A和异绿原酸C 10种多酚类化合物的定量分析方法,研究不同产地及不同采收时期大叶冬青叶中10种多酚类化合物的含量差异及其抗氧化活性。采用HPLC测定大叶冬青叶50%甲醇提取液中10种多酚类成分的含量,并选用DPPH法对其抗氧化活性进行初步探索。结果表明,10种多酚类化合物分离效果较好,标准曲线在检测范围内具有良好的线性(r>0.999 5),平均加样回收率在96.58%～112.03%,RSD<4%(n=6)。大叶冬青叶50%甲醇提取液抗氧活性良好。本实验建立的方法快速、准确、重复性好,可用于同时测定大叶冬青叶中新绿原酸、绿原酸、隐绿原酸、咖啡酸、对羟基肉桂酸、芦丁、异槲皮苷、异绿原酸B、异绿原酸A、异绿原酸C 10种成分的含量;不同产地、不同采收时期大叶冬青叶中10种多酚类化合物含量存在一定差异;不同来源大叶冬青叶50%甲醇提取液抗氧化能力具有明显差异。     

The relationship between the amount of insect-repelling phenolic compounds in pennywort tea and the number of infesting cigarette beetles in the tea bag during one-year storage

Cigarette beetle, Lasioderma serricorne (F.), is a common food-product pest widely found in homes. This paper investigated the relationship between the number of infesting cigarette beetles and the phenolic content of pennywort tea made from young and mature leaves during one-year storage. It was found that cigarette beetles started to appear in tea bags after six months of storage. More adults were found than larvae and pupae. In addition, the number of cigarette beetles infesting pennywort tea made from mature leaves was higher than when it was made from young leaves. The amount of phenolic compounds in pennywort tea was analyzed by Folin–Ciocalteau assay. The results of a regression analysis indicated that the number of adult cigarette beetles correlated negatively with the amount of phenolic compounds in pennywort tea made from young leaves – when the total phenolic content decreased, the number of infesting cigarette beetles increased (r² = 0.80). The number of larvae and pupae showed a weak negative correlation with the amount of phenolic compounds (r² = 0.40 and r² = 0.56, respectively). Similar correlations were found in pennywort tea made from mature leaves, but the number of infesting beetles was higher due to the lower phenolic content of the mature leaves.