6种丁香花挥发性成分的动态顶空吸附ATD-GC/MS分析（英文）

丁香是一种重要的芳香木本观赏植物,花开繁茂,芳香浓郁。该研究采用活体植物动态顶空套袋-吸附法收集了香雪丁香、花叶丁香、关东丁香、蓝丁香、小叶丁香、四季蓝丁香6种不同丁香花的挥发物,通过自动热脱附-气质联用分析技术分析丁香花的挥发物成分,为研究其花香释放机理、进一步开发利用丁香资源及新品种选育提供依据。结果表明:(1)在6种丁香花挥发物中共检测到80种成分,分别属于苯形烃、萜类、醇、醛、酮、脂肪烃、酯、酸及其它类。(2)花叶丁香花的挥发物释放量最高,且为释放量最低的四季蓝丁香的1.8倍。(3)除香雪丁香外其他5种丁香花的挥发物中苯形烃在9类挥发物成分中含量最多,而萜类是香雪丁香花挥发物的主要成分。(4)乙苯、间二甲苯、对二甲苯、二丁基羟基甲苯、2-乙基-1-己醇、5-乙基-2,2,3-三甲基庚烷这6种成分在不同丁香花挥发物成分中含量均较高,是6种丁香花挥发物的主要成分。     

钝叶榕榕果挥发物成分及其构成特征分析

为揭示钝叶榕与其传粉榕小蜂及两种协同进果的非传粉榕小蜂Diaziella yangi和Lipothymus sp.间的化学联系与分配机制,采用顶空动态法提取钝叶榕(Ficus curtipes Corner)雌花期和传粉后的榕果挥发物,用定性和定量的方法鉴定、分析了挥发物的成分和变化动态。结果表明:从钝叶榕榕果中共鉴定出45种挥发物成分,主要是单萜类和倍半萜类化合物。6-甲基-5-庚烯-2-酮、β-罗勒烯、反-β-金合欢烯、α-金合欢烯、α-派烯、香桧烯、顺-β-罗勒烯、顺-β-香柠檬烯、大香叶烯D和4,8-二甲基-1,3,7-壬三烯可能是构建钝叶榕特异性化学信息的基础。雌花期榕果挥发物释放量明显高于传粉后挥发物的释放量,且两者在时间和空间上存在异质性。这说明榕蜂育幼繁殖系统间存在着化学信息的联系。     

不同番茄品种挥发物对B型烟粉虱寄主选择行为的影响

采用顶空固相微萃取和气相色谱-质谱法鉴定了6个番茄品种(浙杂809、浙杂203、合作903、凯特一号、黄椭圆和金妃)植株挥发物的成分,并利用Y型嗅觉仪测定了烟粉虱对不同番茄品种植株及其挥发物的嗅觉反应.结果表明:从6个番茄品种中共鉴定出13种化合物,其主要成分为萜类化合物,品种间挥发物的组成成分和各成分所占比例存在差异.(+)-3-蒈烯和β-石竹烯对B型烟粉虱的驱避性较其他萜类强.烟粉虱对含萜类挥发物种类多、比例高的品种(如浙杂809和浙杂203)选择性较弱,而对含萜类挥发物种类少、比例低的品种(如黄椭圆和金妃)选择性较强.     

柑橘凤蝶成虫虫体挥发物成分及触角电位反应研究

[目的]蝴蝶虫体的气味是识别同类和异性的重要信息来源.本研究通过分析柑橘凤蝶Papilio xuthus雌雄蝶羽化后挥发物的变化规律,并比较了未交配雌雄蝶对挥发物的触角电位(EAG)反应,为下一步探讨柑橘凤蝶求偶时嗅觉的利用提供依据.[方法]使用顶空固相微萃取(HS-SPME)提取柑橘凤蝶挥发物,并通过气质联用仪(GC-MS)分析SPME提取物中的主要成分,采用触角电位仪(EAG)测定柑橘凤蝶Papilio xuthus对挥发物的触角电位反应.[结果]雌雄蝶羽化后共检测到14类挥发物,主要包括醇类和酯类,其中酯类、萜类在羽化后均有出现.交配时雌雄蝶均共有且含量较高的挥发物有2种(2-乙基己醇、2-乙基己基乙酸酯),交配时雄蝶特有挥发物仅1种(α-法呢烯),未检测到雌蝶特有的挥发物.柑橘凤蝶雌雄蝶从交配前到交配后,其体内的2-乙基己醇、2-乙基己基乙酸酯和α-法呢烯的含量都变化明显.在交配前及交配时2-乙基己醇和α-法呢烯含量增加,而2-乙基己基乙酸酯的含量减少,表明在交配时,可能有大量的2-乙基己醇、2-乙基己基乙酸酯和c-法呢烯释放到体外.并且未交配雌雄蝶对2-乙基己醇、2-乙基己基乙酸酯和c-法呢烯EAG反应均明显高于对照.[结论]根据雌雄蝶羽化后挥发物变化规律及触角电位试验初步检验,推测2-乙基己醇、2-乙基己基乙酸酯在柑橘凤蝶同种识别及同性识别中起作用,特有的挥发物α-法呢烯在柑橘凤蝶同种异性的识别中起作用.     

外用不同浓度茉莉酸甲酯诱导的茶树挥发物的种类和时序变化

【目的】明确MeJA对茶树挥发物的诱导作用。【方法】采用顶空活体取样法对不同浓度MeJA处理后的茶苗挥发物进行抽提,并利用GC-MS对挥发物进行鉴定。【结果】不同剂量MeJA显著地影响茶树挥发物的种类组成和释放量,50μL MeJA处理可显著诱导茶树释放香叶烯、萜品油烯、罗勒烯等10种单萜类化合物,法呢烯、橙花叔醇和红没药烯等7种倍半萜类化合物,苯甲醇、苯乙腈和吲哚等5种氨基酸衍生物,以及3种未知化合物;而100μL MeJA处理仅能诱导茶树释放7种化合物。不同挥发物对MeJA处理的响应时间不同,但其释放量都具有昼高夜低的趋势。并且,释放量的大小明显受到光照强度的影响。【结论】外用MeJA喷雾处理可诱导茶树挥发物的产生和释放。     

六种同域分布雌雄异株榕树挥发物多样性与系统发育一致性

植物花挥发物是维持昆虫-植物传粉互作的重要化学信号，其组成的多样性对于理解传粉昆虫与植物相互作用的形成、维持和进化具有重要意义。榕树与其传粉榕小蜂是一种专性的互惠共生关系，榕树为榕小蜂提供繁殖场所，榕小蜂为榕树传粉。而榕果雌花期（接收期）释放的特异性挥发物是维持双方相互作用的关键媒介。本研究以西双版纳地区同域分布的6种雌雄异株榕树为研究对象，用固相微萃取和气相色谱质谱联用仪对雌花期榕果的挥发物组成进行了分析。共发现77种化合物，包含脂肪酸类衍生物6种、单萜类化合物16种、倍半萜类衍生物50种和芳香族化合物5种，不同化合物对挥发物距离差异性的贡献率依次是：对甲基苯甲醚（4-methylanisole，2.15）、β-罗勒烯（β-Ocimene，0.84）和喜沙木烯（Prezizaene，0.73）。不同物种间挥发物组成有显著的差异，且挥发物的差异与榕树系统发育距离具有正相关性，但同一物种不同性别间的挥发物组成上没有显著的差异。本研究中发现雌雄异株榕树挥发物组成具有多样性高、种内性别间相似、种间差异大，系统发育一致性的特点，上述特点在榕树物种分化以及维持雌雄异株榕树繁殖的化学通讯机制中可能发挥着关键作用。     

斜纹夜蛾取食对Bt玉米挥发物组成和含量的影响

采用顶空吸附法和气相色谱-质谱法研究了两个Bt玉米品种(5422Bt1, 5422CBCL)和一个同源常规玉米品种(5422)在健康和经斜纹夜蛾取食危害后两种状态下释放的挥发物组成和含量差异.结果表明：健康状态下,5422释放了(E)-β-罗勒烯、芳樟醇、（3E）-4,8-二甲基-1,3,7-壬三烯(DMNT)和(E)-β-法尼烯4种挥发物;5422Bt1释放了芳樟醇和DMNT 2种挥发物;而5422CBCL只释放芳樟醇1种挥发物.虫害后,在5422和5422Bt1的挥发物中鉴定出了萜类、醇类、 酯类和吲哚等12种化合物;在5422CBCL中鉴定出了10种,缺少(Z)-3-己烯-1-醇乙酸酯和橙花叔醇;3个品种释放的萜烯类化合物种类和含量均明显增加,其中,5422和5422Bt1增加了8种,5422CBCL增加了7种;5422Bt1和5422CBCL 的芳樟醇和DMNT释放量高于5422,其余化合物的释放量均低于常规品种,尤其是(E)-β-法尼烯显著低于5422.可见,经斜纹叶蛾取食诱导后,Bt玉米释放的挥发物种类和含量与常规玉米不同,且不同的Bt玉米品种（Bt11与MON810）之间也存在差异.     

竹叶精油和头香的OGC—MS—DS研究

本文以阔叶箬竹,毛金竹和四季竹为代表,用SDE法和大孔树脂顶空吸附法联合收集芳香成分,用毛细管气相色谱／质谱／计算机用（CGC／MS／DS）技术,对竹叶的精油和头香进行剖析,共检出144种挥发性化合物,其中22种为三种竹叶所共有,芳香成分以醛,醇,呋喃,酮类为主,C5－C8中等链长的含氧化合物占主导地位,是竹叶清香的物质基础,其中C6化合物起了关键作用,重要的C6尬发有（E）－2－乙烯醛,（Z）－3－乙烯醇,2－乙基－呋喃,己醛和己烯等。     

美凤蝶成虫虫体挥发物的主要成分与变化动态研究

挥发物在蝴蝶种内识别、交配繁衍等过程中作用关键。本文旨在研究美凤蝶Papilio memnon成虫虫体挥发物的变化规律,为下一步探索蝴蝶虫体挥发物作为嗅觉信号的组成成分在求偶过程中的作用提供基础资料。应用固相微萃取方法分别收集美凤蝶雌雄成虫的虫体挥发物,用GC-MS（气相色谱-质谱）技术对挥发物进行分析和比较。结果显示,羽化后的雌雄蝶可检测到烷烃类、烯烃类、炔烃类、芳香类、醇类、醛类、酯类、酸类等12类挥发物,其中芳香类、酯类、酸类在羽化后均有出现。交配前,雌雄蝶挥发物分别有14种和16种,其中14种为共有,而以反-2-辛烯醛（雌：59.88%,雄：77.99%）和2-甲基烯丙醇（雌：14.47%,雄：8.42%）相对含量较高。交配时,雌雄蝶挥发物分别增加到24种和21种,其中20种为共有,优势挥发物除反-2-辛烯醛（雌：53.75%,雄：39.62%）和2-甲基烯丙醇（雌：9.36%,雄：11.04%）外,还包括1-二十醇（雌：10.46%,雄：21.13%）。另外,雌蝶交配时有4种特有挥发物（1-茚酮、异辛酸、1-苯基-1-丙炔、紫苏醛）,而雄蝶仅1种（β-石竹烯）。然而,一旦交配后,以上优势挥发物与交配时雌雄蝶特有挥发物均未检测到。推测2-甲基烯丙醇、反-2-辛烯醛和1-二十醇可能在美凤蝶种内识别过程中发挥作用,而1-茚酮、异辛酸、1-苯基-1-丙炔、紫苏醛和β-石竹烯则可能在求偶交配期间具有增强雌雄个体识别或相互吸引等作用。     

不同危害状态下寄主山核桃挥发物成分的比较及桑天牛对其组分的GC-EAD和行为反应

【目的】挖掘能影响桑天牛Apriona germari行为反应的山核桃Juglans mandshurica挥发物,为筛选桑天牛的植物源引诱剂或驱避剂提供理论依据。【方法】采用动态顶空套袋法收集不同危害状态[健康(CK)以及桑天牛取食、产卵和钻蛀危害]下山核桃释放的挥发物,并利用气相色谱-质谱联用仪(GC-MS)、气相色谱-触角电位测量系统(GC-EAD)及Y型嗅觉仪分析鉴定出桑天牛成虫对其产生电生理及行为反应的挥发物。【结果】不同危害状态下山核桃释放的挥发物皆以萜烯类和芳香族化合物居多,且有多种成分相对含量存在显著性差异,其中每种危害状态下山核桃释放的挥发物都有一种或几种特有的成分。桑天牛成虫仅对不同危害状态下山核桃释放的蒎烯、乙酸叶醇酯、壬醛、α-萜品醇、丙烯酸-2-乙基己酯及正十六烷6种挥发物产生显著的电生理反应,对其他挥发物无反应,其中雌成虫对壬醛的电生理反应最强,而雄成虫对乙酸叶醇酯的电生理反应最强。嗅觉反应结果显示,丙烯酸-2-乙基己酯仅对桑天牛雌成虫有显著的引诱作用(P0.05),而乙酸叶醇酯则仅对雄成虫有极显著的引诱作用(P0.01);壬醛对桑天牛雌雄成虫均有显著的引诱作用(P0.05),而α-萜品醇则对其有显著的驱避作用(P0.05)。【结论】本研究结果表明,乙酸叶醇酯、壬醛和丙烯酸-2-乙基己酯对桑天牛成虫有较强的引诱作用,而α-萜品醇则对其有较好的驱避作用。     

毛霉蛋白酶的研究

蛋白酶是食品工业中最重要的加工配料(辅料)之一,蛋白酶在食品加工中的应用主要是利用了其对蛋白质所产生的多样化水解作用[1-2]。许多受人欢迎的食品,如干酪、啤酒和酱油等的生产过程都包含蛋白酶催化蛋白质水解这一关键性的反应。对这些食品加工技术的改进体现在,基于对这些加工过程所涉及的各种     

Coronatine analogues produced by Xanthomonas campestris pv Phormiicola

Liquid cultures of Xanthomonas campestris pv phormiicola were found to contain two analogues of coronatine lacking the cyclopropane ring structure, and no trace of either coronatine or norcoronatine. The two compounds were isolated and fully characterised by NMR, MS, hydrolysis and GC of hydrolysis products, as N-coronafacoyl- -valine and N-coronafacoyl- -isoleucine. A survey of 12 strains from 10 other X. campestris pathovars did not locate another source of production of these compounds, whereas all three strains of X. campestris pv phormiicola examined produced comparable levels of both compounds. This is the first report of phytotoxins biosynthetically derived from coronafacic acid outside of the genus Pseudomonas. The implications of these findings to the biosynthesis of the cyclopropane ring structure of coronatine are discussed.     

Hydroxylation of steroids by Fusarium oxysporum, Exophiala jeanselmei and Ceratocystis paradoxa

The potential of Fusarium oxysporum var. cubense UAMH 9013 to perform steroid biotransformations was reinvestigated using single phase and pulse feed conditions. The following natural steroids served as substrates: dehydroepiandrosterone (1), pregnenolone (2), testosterone (3), progesterone (4), cortisone (5), prednisone (6), estrone (7) and sarsasapogenin (8). The results showed the possible presence of C-7 and C-15 hydroxylase enzymes. This hypothesis was explored using three synthetic androstanes: androstane-3,17-dione (9), androsta-4,6-diene-3,17-dione (10) and 3α,5α-cycloandrost-6-en-17-one (11). These fermentations of non-natural steroids showed that C-7 hydroxylation was as a result of that position being allylic. The evidence also pointed towards the presence of a C-15 hydroxylase enzyme.The eleven steroids were also fed to Exophialajeanselmei var. lecanii-corni UAMH 8783. The results showed that the fungus appears to have very active 5α and 14α-hydroxylase enzymes, and is also capable of carrying out allylic oxidations.Ceratocystis paradoxa UAMH 8784 was grown in the presence of the above-mentioned steroids. The results showed that monooxygenases which effect allylic hydroxylation and Baeyer–Villiger rearrangement were active. However, redox reactions predominated.     

耐辐射奇球菌pprM基因增强大肠杆菌氧化抗性的研究

目的:探讨耐辐射奇球菌ppr M基因对大肠杆菌氧化抗性的影响。方法:氯化钙法转化分别构建含pGEX-6p-1-pprM质粒的大肠杆菌DH5α。测定不同浓度过氧化氢对含pGEX-6p-1-pprM、pGEX-6p-1和野生型大肠杆菌DH5α活性的影响以及菌体内SOD/GSH/CAT水平的变化。结果:与空质粒组和野生型组相比,含pprM的大肠杆菌在同浓度过氧化性情况下,其抑菌圈明显缩小,差异有统计学意义。与空质粒组和野生型组相比,含pprM的大肠杆菌体内CAT活力、SOD活性明显提高,但GSH量并没有明显提高。结论:pprM基因能够提高大肠杆菌抗氧化能力,其机制可能与pprM基因增强细菌体内抗氧化酶的活性有关。     

Suppression of maize root diseases caused by Macrophomina phaseolina, Fusarium moniliforme and Fusarium graminearum by plant growth promoting rhizobacteria

A plant growth-promoting isolate of a fluorescent Pseudomonas sp. EM85 and two bacilli isolates MR-11(2) and MRF, isolated from maize rhizosphere, were found strongly antagonistic to Fusarium moniliforme, Fusarium graminearum and Macrophomina phaseolina, causal agents of foot rots and wilting, collar rots/stalk rots and root rots and wilting, and charcoal rots of maize, respectively. Pseudomonas sp. EM85 produced antifungal antibiotics (Afa⁺), siderophore (Sid⁺), HCN (HCN⁺) and fluorescent pigments (Flu⁺) besides exhibiting plant growth promoting traits like nitrogen fixation, phosphate solubilization, and production of organic acids and IAA. While MR-11(2) produced siderophore (Sid⁺), antibiotics (Afa⁺) and antifungal volatiles (Afv⁺), MRF exhibited the production of antifungal antibiotics (Afa⁺) and siderophores (Sid⁺). Bacillus spp. MRF was also found to produce organic acids and IAA, solubilized tri-calcium phosphate and fixed nitrogen from the atmosphere. All three isolates suppressed the diseases caused by Fusarium moniliforme, Fusarium graminearum and Macrophomina phaseolina in vitro. A Tn5:: lac Z induced isogenic mutant of the fluorescent Pseudomonas EM85, M23, along with the two bacilli were evaluated for in situ disease suppression of maize. Results indicated that combined application of the two bacilli significantly (P = 0.05) reduced the Macrophomina-induced charcoal rots of maize by 56.04%. Treatments with the MRF isolate of Bacillus spp. and Tn5:: lac Z mutant (M23) of fluorescent Pseudomonas sp. EM85 significantly reduced collar rots, root and foot rots, and wilting of maize caused by Fusarium moniliforme and F. graminearum (P = 0.05) compared to all other treatments. All these isolates were found very efficient in colonizing the rhizotic zones of maize after inoculation. Evaluation of the population dynamics of the fluorescent Pseudomonas sp. EM85 using the Tn5:: lac Z marker and of the Bacillus spp. MRF and MR-11(2) using an antibiotic resistance marker revealed that all the three isolates could proliferate successfully in the rhizosphere, rhizoplane and endorhizosphere of maize, both at 30 and 60 days after seeding. Four antifungal compounds from fluorescent Pseudomonas sp. EM85, one from Bacillus sp. MR-11(2) and three from Bacillus sp. MRF were isolated, purified and tested in vitro and in thin layer chromatography bioassays. All these compounds inhibited R. solani, M. phaseolina, F. moniliforme, F. graminearum and F. solani strongly. Results indicated that antifungal antibiotics and/or fluorescent pigment of fluorescent Pseudomonas sp. EM85, and antifungal antibiotics of the bacilli along with the successful colonization of all the isolates might be involved in the biological suppression of the maize root diseases.     

Biocontrol of Sclerotinia lettuce drop by Coniothyrium minitans and Trichoderma hamatum

Fungal isolates, with known activity against Sclerotinia spp. in laboratory assays, were tested for their ability to control Sclerotinia minor in four field experiments (1998–2000). In the first experiment, eight fungal isolates (Trichoderma hamatum LU595, LU593, LU592, Trichoderma virens LU555 and LU556, Coniothyrium minitans LU112, Clonostachys rosea LU115 and Trichoderma rossicum LU596) were evaluated by incorporating spore suspensions into transplant potting mix and planting lettuce seedlings into a S. minor infested field site. At harvest, Trichoderma hamatum LU595, LU593, T. virens LU555 and C. minitans LU112 reduced disease by 30–50% compared with the untreated control under very high disease pressure (100%). In further field experiments C. minitans LU112 and T. hamatum LU593, applied as maizemeal–perlite soil amendments or incorporated into the potting mix, reduced S. minor disease over a range of disease pressures (29–91%). Disease control was equivalent or greater than that achieved with the standard carbendazim fungicide treatment. Both isolates were shown to effectively colonize the lettuce rhizosphere and surrounding soil and this colonization may have protected the roots from infection by S. minor. Multiple applications of C. minitans LU112 or T. hamatum LU593 formulations gave no added disease control compared with a single application at planting. Commercial formulations of both C. minitans LU112 and T. hamatum LU593 applied as transplant treatments, solid substrate soil amendments or as a spore drench gave consistent disease control and are currently being developed further.     

Management Fusarium wilt on melon and watermelon by Penicillium oxalicum

The potential of the biological control fungus Penicillium oxalicum to suppress wilt caused by Fusarium oxysporum f. sp. melonis and F. oxysporum f. sp. niveum on melon and watermelon, respectively, was tested under different growth conditions. The area under disease progress curve of F. oxysporum f. sp. melonis infected melon plants was significantly reduced in growth chamber and field experiments. In glasshouse experiments, it was necessary to apply P. oxalicum and dazomet in order to reduce Fusarium wilt severity in melons caused by F. oxysporum f. sp. melonis. For watermelons, we found that P. oxalicum alone reduced the area under the disease progress curve by 58% in the growth chamber experiments and 54% in the glasshouse experiments. From these results, we suggested that P. oxalicum may be effective for the management of Fusarium wilt in melon and watermelon plants.     

Insertion mutations at the maizeOpaque2 locus induced by transposable element familiesAc, En/Spm andBg

Eight independently isolated unstable alleles of theOpaque2 (O2) locus were analysed genetically and at the DNA level. The whole series of mutations was isolated from a maize strain carrying a wild-typeO2 allele and the transposable elementActivator (Ac) at thewx-m7 allele. Previous work with another unstable allele of the same series has shown that it was indeed caused by the insertion of anAc element. Unexpectedly, the remaining eight mutations were not caused by the designatedAc element, but by other insertions that are structurally similar or identical to one of two different autonomous transposable elements. Six mutations were caused by the insertion of a transposable element of theEnhancer/Suppressor-Mutator (En/Spm) family. Two mutations were the result of the insertion of a transposable element of theBergamo (Bg) family. Genetic tests carried out with plants carrying the unstable mutations demonstrated that all were caused by the insertion of an autonomous transposable element.     

CRISPR/Cas9介导靶向敲除拟南芥GGB基因突变体的鉴定

GGB是抗旱负调控基因。为了获得拟南芥ggb突变体材料,构建了以拟南芥U6启动子驱动GGB sgRNA的CRISPR/Cas9基因组编辑载体。将构建好的编辑载体利用农杆菌介导的浸花法转化野生型拟南芥。对转基因后代GGB基因的测序结果分析发现,在靶位点处有缺失4个碱基和增加1个T碱基的2种突变体产生。分别对野生型拟南芥和上述2种ggb突变体进行半定量RT PCR分析结果显示,突变体材料中几乎检测不到GGB基因表达,说明获得了GGB基因敲除突变体。对野生型和ggb突变体叶片失水率、耐旱表型及单株种子量的测定结果表明,与野生型相比,拟南芥GGB基因突变后,叶片失水率显著减少,抗旱性明显增强,而单株种子量却并没有改变。研究表明,GGB是一种理想的作物分子育种的候选靶基因,获得的突变体为今后从农作物中克隆的GGB同源基因进行功能互补验证提供了有用的遗传材料。