古里雅冰芯中生物有机酸的初步分析

甲酸、乙酸是全球对流层中普遍存在的化学成分，它们对偏远地区降水中的酸度有很大影响，降水中存在的甲酸、乙酸必然会在冰川和冰盖中保存下来．然而，目前很少有文章报道山地冰川中甲酸、乙酸的测定结果及环境意义．我们用离子色谱法测定了古里雅上部５ｍ冰芯中甲酸、乙酸的浓度，结果显示，甲酸、乙酸具有明显的季节变化，峰值一般对应于夏季层位，说明甲酸、乙酸的来源不同于阳离子，粉尘不是其主要来源．将甲酸、乙酸的记录与冰芯中δ１８Ｏ和阳离子的记录对比，得出甲酸具有较敏感的气候指示意义．

雪冰中生物有机酸的测试分析方法研究

生物有机酸是构成酸雨的组分类别 ,对地表环境有着重要影响 .由于其来源与生物界关系密切 ,因此 ,对其在雪冰中记录的研究是从历史的角度认识C、H、O等生源元素生物地球化学循环 ,认识过去生态和环境变化的途径之一 .但是 ,由于其含量较低、易遭受污染等原因 ,雪冰中有机酸含量的定量测定一直是困扰研究人员的一个问题 .在对目前有机酸测试分析现状、测试分析的难点和问题调研的基础上 ,文章提出了一种利用DX - 30 0离子色谱测试山地冰川雪冰中生物有机酸含量的方法 .该方法利用AS4A分析柱 ,AG4A保护柱 ,TAC - 2样品富集柱和ATC - 1阴离子捕集柱 ,以梯度淋洗方式 ,在 14min内可分离检测出甲酸、乙酸、丙酮酸、甲烷磺酸、草酸等有机酸根离子及氟、氯、亚硝酸 ,硝酸、溴、磷酸和硫酸等常见无机阴离子 .上述有机、无机离子的测试分析相对标准误差分别为 :氟(2 0 % )、乙酸 (4 5 % )、甲酸 (2 0 % )、甲烷磺酸 (16 9% )、氯 (3 1% )、亚硝酸 (3 9% ) ,硝酸 (2 2 % )、溴 (4 9% )和硫酸 (2 4% )

白背叶楤木中的有机酸衍生物及甾醇类化学成分

目的对白背叶楤木(Aralia chinensis L.var.nuda Nakai)乙酸乙酯部位有机酸衍生物及甾醇类化学成分进行研究。方法利用硅胶、反相RP-18、凝胶Sephadex LH-20、HPLC等色谱方法进行分离纯化,并运用MS、NMR等波谱方法鉴定化合物的结构。结果从白背叶楤木的乙酸乙酯部位中分离鉴定了14个有机酸衍生物及甾醇类化合物,分别鉴定为十五烷醇(pentadecanol,1)、三十四烷醇(tetratriacontanole,2)、十五烷酸(pentadecanoic acid,3)、十七烷酸(heptadecanoic acid,4)、二十烷酸(arachidic acid,5)、balansenateⅠ(6)、壬二酸二甲酯(methyl azelate,7)、α-亚麻酸甲酯(methyl linolenate,8)、二十八烷醇(octacosanol,9)、十六烷酸(palmitic acid,10)、豆甾醇(sitosterol,11)、α-菠甾醇-3-O-β-D-吡喃葡萄糖苷(α-spinasterol-3-O-β-D-glucopyranoside,12)、豆甾醇-3-O-β-D-葡萄糖苷(3-O-β-D-glucopyranosyl-stigmasterol,13)、β-谷甾醇(β-sitosterol,14)。结论化合物1~8、11~14均为首次从该植物中分离得到,其中,化合物1~8、11~13为首次从楤木属植物中分离得到,化合物1~7、12~13为首次从五加科植物中分离得到。

天山乌鲁木齐河源一号冰川冰芯中生物有机酸记录及其与南北极地区的差异

天山乌鲁木齐河源一号冰川为一中纬度山谷冰川，其冰芯中所记录的生物有机酸计有甲酸、乙酸、草酸和丙酮酸，最近 ４０年其平均含量分别为（１０２．８± １４７．３），（３９２．３± ３９０．８），（６．９± １４．８）和（４．２±８．３） ｎｇ／ｇ．甲酸／乙酸平均值为 ０．３４±０．４３．这些生物有机酸源于乌鲁木齐河源周边城市工业生产和人类生活对大气的污染．与极地地区相比，该地区的有机酸远远高于格陵兰和南极洲相应组成的含量，且未经远距离传输和复杂的大气化学反应．

乌鲁木齐河源1号冰川表层雪的化学特征——以低分子有机酸和无机阴离子为例

表层雪是联系大气成分与冰芯记录的重要纽带,是研究成冰作用过程中化学组成变化的起点.为配合天山乌鲁木齐河源1号冰川成冰作用过程中化学组成变化的研究,对1号冰川积累区(海拔4130 m)一个完整年度的表层雪样品进行了低分子有机酸和无机阴离子含量的分析.结果显示:表层雪中低分子有机酸主要有HCOO-、CH3COO-、C2H5COO-和(COO)22-,无机阴离子主要有F-、Cl-、NO2-、NO3-、SO42-和PO43-.除(COO)22-外,大部分高浓度的有机酸和无机阴离子因受到周围环境和盛行风的影响呈现出明显的季节变化特征,即夏半年离子浓度变化剧烈,最大值和最小值同时出现在夏半年,冬半年的浓度则相对小而稳定;而(COO)22-和低浓度的无机阴离子随季节变化的特征不明显,在全年均显示出波动性.在外界条件不变的情况下,表层雪可以长时间(至少半年时间)保存其中高含量的化学组成不被改变.

大气低分子有机酸研究方法及其前沿问题

文章系统地阐述了大气有机酸的研究历史、现状和目前存在问题及可能取得研究进展的方法。低分子有机酸是大气中重要的微量挥发性有机碳组分,它们广泛存在于大气对流层中,对气候、环境和生态系统具有重要影响。长期以来,对大气有机酸的研究都是基于其含量的分析,尽管这一研究手段对有机酸的认识起到了推动作用,但含量的分析已越来越不能满足于当前人们对大气有机酸生物地球化学认识的需求。由于稳定同位素组成的示踪作用,近年来人们开始探索利用有机酸中碳同位素的测试分析方法来研究其循环过程。这一方法涉及水溶液中有机酸的萃取过程。由于其近发、半挥发性和其易污染性,常规的萃取方法不能应用于有机酸的萃取。最近出现的固相微萃取技术为有机酸碳同位素组成的准确分析研究提供了可能的途径。利用这一方法探索有机酸同位素组成的分析,有可能为大气有机酸生物地球化学循环研究开辟一片新的天地,从而使该领域研究向前推进一步。

蓟马取食对苜蓿有机酸及其衍生物的影响

为探究蓟马危害对苜蓿有机酸及其衍生物的影响,以‘草原2号’杂花苜蓿和‘草原4号’紫花苜蓿为试验材料,分别进行牛角花齿蓟马接种和未接种处理,测定苜蓿叶片中有机酸总含量、苹果酸含量、pH值,以及有机酸及其衍生物的种类和含量。结果表明:蓟马接种和未接种处理中,‘草原2号’苜蓿有机酸总含量及苹果酸含量均显著高于‘草原4号’苜蓿,但两者之间pH值无显著差异。‘草原2号’和‘草原4号’苜蓿叶片中共检测到18种差异有机酸及其衍生物,其中‘草原4号’苜蓿的9种有机酸及其衍生物含量显著高于‘草原2号’苜蓿,另外9种的含量显著低于‘草原2号’苜蓿。蓟马侵染后,‘草原2号’苜蓿的12种有机质酸及其衍生物含量显著增加,而‘草原4号’苜蓿的10种有机质酸及其衍生物含量显著增加。有7种有机酸及其衍生物在2个苜蓿品种中均受到蓟马危害诱导。

壳聚糖酰胺衍生物保湿性能研究

壳聚糖具有良好的保湿性能 ,但由于不溶于水 ,因此在化妆品中难以应用。虽然它能溶于酸溶液中 ,但会发生降解而不稳定。壳聚糖可与生物有机酸反应制得壳聚糖N -酰化的衍生物 ,2 %的该类衍生物 ,其保湿性明显优于10 %的甘油水溶液 ,而且粘度稳定 ,无降解发生 ,故可在化妆品中用作保湿剂。

Organic Acids Secreted from Plant Roots under Soil Stress and Their Effects on Ecological Adaptability of Plants

[Objective] In this study,the secretion of organic acids from plant roots under soil nutrient and water stress and the effects of organic acids on ecological adaptability of plants were investigated,which provided theoretical basis for improving the adaptability of plants to a variety of stress conditions.The results showed that,under nutrient and water stress,the content of organic acids secreted from plant roots increased significantly as a common active adaptive response.Organic acids could improve the activities of a variety of antioxidant enzymes,contents of osmotic regulatory substances,contents of chlorophyll and photosynthesis levels,promote nutrient absorption and transportation in plants,and ultimately contribute to plant growth and biomass accumulation,reduce the toxicity of stress conditions to plants and improve the stress resistance and adaptability of plants.

2010年以来获得的国家自然科学基金项目

序号项目名称项目负责人立项年度l冷藏陈列柜耦合节能的系统多尺度方法研究2离子液体及其在清洁化工中的应用基础研究，基于等离子体聚合一稀土配位技术的稀土碳纳米管的设计构筑。及其聚合物材料构效研究。贵金属纳米团簇粒子在生物有机酸体系中的控制生长及其功能。

Tomato Growth and Organic Acid Changes in Response to Partial Replacement of NO_3^--N by NH_4^+-N

A hydroponic experiment was conducted to study the effect of partial replacement of NO-3-N by NH4+-N on the seedling growth and organic acid content of tomato (Lycopersicon esculentum Mill.). A completely randomized design was established with three replications and five treatments, i.e., NO-3-N/NH4+-N of 100/0, 75/25, 50/50, 25/75 and 0/100. Results showed that 25% replacement of NO3--N by NH4+-N significantly (P = 0.05) improved fresh and dry weight, revealing that a proper percentage of NH4+-N was important for tomato nitrogen nutrition. This could increase the plant growth even though tomato was a crop that preferred nitrate nutrition. Also an increase in the proportion of NH4+-N in the nutrient solution led to a significant decrease (P = 0.05) in malate, citrate and fumarate. However, the 25% NH4+-N plus 75% NO3--N treatment had no significant effect (P = 0.05) on the 2-ketoglutarate, succinate or oxalic acid content, showing that only some organic acids in tomato plants were affected. Only pyruvate increased significantly (P = 0.05), and it only increased for 25% and 50% replacement of NO3--N by NH4+-N. Metabolism of these organic acids, especially malate, citrate and fumarate, should be further studied at the molecular level in vegetables applied with different nitrogen forms.

Low-Molecular-Weight Aliphatic Acids in Soils Incubated with Plant Residues Under Different Moisture Conditions

Incubation experiments were conducted to investigate the dynamics of low- molecufar-weight aliphatic acids in two andosols with and without plant materials. Results showed that amount of low- molecular-weight aliphatic acids in soils alone varied considerably with water regime under which the soil was incubated,duration of incubation and soil organic matter content, ranging from 257-860 pmol kg-1 soil I of which 19%～33% was in free state. Incorporation of plant materials increased greatly both the amount and number of members of low- molecular- weight aliphaticacidst and also the proporticn of low-molec "far-weight aliphatic acids occurred in free state. Generally, among these aliphatic acids detected, acetic, propionic, glyoxalic and formic acids were predominant.

The Burial of Biogenic Silica, Organic Carbon and Organic Nitrogen in the Sediments of the East China Sea

We sampled the sediments of the East China Sea during 2005 and 2006, and analysed the contents of the biogenic matters: biogenic silica, organic carbon, and organic nitrogen. From the surface distribution we found the contents of these substances to be in the ranges of 0.72%-1.64%, 0.043%-0.82%, and 0.006%-0.11%, respectively. Their distributions were similar to each other, being high inside the Hangzhou Bay and low outside the bay. The vertical variations of the contents were also similar. In order to discuss the relation between them we analysed the variations of content with depth. They increased in the first 7 cm and then decreased with depth. The peaks were found at depths between 20 to 25 cm. The distribution of carbonate showed an opposite trend to that of biogenic matters. The content of total carbon was relatively stable with respect to depth, and the ratio of high organic carbon to carbonate showed a low burial efficiency of carbonate, which means that the main burial of carbon is organic carbon. In order to discuss the source of organic matters, the ratio of organic carbon to organic nitrogen was calculated, which was 8.01 to 9.65, indicating that the organic matter in the sediments was derived mainly from phytoplankton in the seawater.

Effects of Organic Fertilizer on Fruit Quality and Acidified Soil Chemical Properties in Yantai Orchard

[Objective] This study aimed to investigate the improving effect of organic fertilizer on acidified soil as well as their effects on fruit quality and quantity in Yantai orchard.[Method] Plot experiment was conducted to investigate the effects of organic fertilizer on fruit yield and quality of Red Fuji and chemical properties of acidified soil.[Result] The apple yield in acidified soil applied with organic fertilizer all increased.Under the application of biological organic fertilizer,the apple yield was higher,and it was 8.92% higher than that in the control group.Under the mixed application of chemical fertilizer and biological organic fertilizer,the growth and development of apple trees were improved,and the total soluble solid(TSS) content,vitamin C(Vc) content and TSS-acid ratio in mature apples all increased.The application of organic fertilizer significantly reduced soil acidity.Compared with those in the control group,the soil p H value,organic matter content and alkali-hydrolyzable nitrogen content under the application of biological organic fertilizer were increased by 8.33%,15.10% and 30.80%,respectively.[Conclusion] The application of biological organic fertilizer could improve the yield of apple in acidified soil.

Mutualistic fungal endophytes produce phytohormones and organic acids that promote japonica rice plant growth under prolonged heat stress

This study identifies the potential role in heat-stress mitigation of phytohormones and other secondary metabolites produced by the endophytic fungus Paecilomyces formosus LWL1 in japonica rice cultivar Dongjin. The japonica rice was grown in controlled chamber conditions with and without P. formosus LWL1 under no stress （NS） and prolonged heat stress （HS） conditions. Endophytic association under NS and HS conditions significantly improved plant growth attributes, such as plant height, fresh weight, dry weight, and chlorophyll content. Furthermore, P. for- mosus LWL1 protected the rice plants from HS compared with controls, indicated by the lower endogenous level of stress-signaling compounds such as abscisic acid （25.71%） and jasmonic acid （34.57%） and the increase in total protein content （18.76%-33.22%）. Such fungal endophytes may be helpful for sustainable crop production under high environmental temperatures.

Prediction of Polycyclic Aromatic Hydrocarbon Bioaccessibility to Earthworms in Spiked Soils by Composite Extraction with Hydroxypropyl-β-Cyclodextrin and Organic Acids

Traditional exhaustive extraction methods often overestimate the risk of polycyclic aromatic hydrocarbon(PAH) bioaccessibility to biota. Therefore, reliable assessment methods need to be established. In this study, a composite extraction with hydroxypropyl-β-cyclodextrin(HPCD) and three low-molecular-weight organic acids, oxalic acid(OA), malic acid(MA), and citric acid(CA), was used to predict the PAH bioaccessibility to earthworms, subjecting to two soils(red soil and yellow soil) spiked with selected PAHs,phenanthrene, pyrene, chrysene, benzo(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, and benzo(a)pyrene. For both soils,concentrations of PAHs by composite extraction using HPCD-OA(R^2= 0.89–0.92, slope = 1.89–2.03; n = 35), HPCD-MA(R^2=0.92–0.96, slope = 1.43–1.67; n = 35), and HPCD-CA(R^2= 0.92–0.96, slope = 1.26–1.56; n = 35) were significantly correlated with PAH accumulation in the Eisenia fetida earthworms. Moreover, the HPCD-CA-and HPCD-MA-extracted PAH concentrations were closer to the earthworm-accumulated PAH concentration than the extraction using just HPCD. The results indicated that the composite extraction could improve the prediction of PAH bioaccessibility, and therefore can serve as a reliable chemical method to predict PAH bioaccessibility to earthworms in contaminated soils.