藻类挥发性有机化合物研究进展

在水域生态系统中, 藻类释放的挥发性有机化合物(VOCs)种类众多, 主要有萜烯类、醛类、醇类、酯类、酮类、脂肪族烃、芳香族、硫化物和卤化物。这些VOCs通过不同的次生代谢途径形成, 可为多种环境因素所诱导产生。在逆境胁迫下, VOCs具有提高藻细胞抗逆性的作用。当VOCs释放到水体中后, 可为同种藻细胞传递胁迫信息, 使感受细胞做好防御准备。对于异种藻细胞, VOCs通过化感作用抑制其生长, 从而保证VOCs释放者的竞争优势。此外, VOCs还可驱避捕食者, 保护藻细胞免受伤害。未被感受者利用的VOCs经挥发进入大气层后, 会参与水域上空二次有机气溶胶的形成。通过对藻类VOCs的种类、形成途径、诱导释放因素及其生态作用进行综述, 以期对藻类VOCs的研究有所帮助。     

Microbial consumption and production of volatile organic compounds at the soil-litter interface

Substantial amounts of volatile organic compounds (VOCs) can be released during decomposition and these compounds can affect atmospheric chemistry, belowground processes, and the structure of microbial communities in litter and soil. However, we have a limited understanding of the types, quantities and ecological impacts of VOCs emitted from litter. Here we used a closed flow-through system and proton transfer reaction mass spectrometry (PTR-MS) to characterize VOC emissions from soil and two litter types (Pinus taeda and Acer rubrum) over a 72-day incubation period. Microbial respiration rates were measured throughout the incubation, and the soils were harvested at the end of the incubation to determine how litter VOCs influenced soil C dynamics, N mineralization rates, and bacterial communities. Using the PTR-MS we identified over 100 VOCs, with 10 VOCs making up the majority of emissions. VOCs accounted for up to 2.5% of the C flux from litter. Soil was a net sink of litter VOCs, absorbing up to 80% of VOCs released by litter, and exposure of soil to litter VOCs increased microbial respiration rates in soil by up to 15%. However, we observed negligible impacts of litter VOCs on soil nutrient levels and bacterial community structure, suggesting that soils must be exposed to higher concentrations of VOCs than observed in our study, to cause effects on these soil characteristics. Overall, VOCs appear to have an important influence on C dynamics at the soil-litter interface and VOC emissions from decomposing litter may represent an understudied component of biosphere–atmosphere interactions.     

植物源VOCs及其对陆地生态系统碳循环的贡献

综述了近20a来国内外关于植物源VOCs的研究进展。分析了植物源VOCs主要组成成分、生理-生态基础,以及影响植物VOCs释放速率的主要因素。重点探讨了植物源VOCs对陆地生态系统碳循环的潜在重要性,提出一些值得关注的问题。     

冷蒿挥发性有机化合物主要成分分析及其地上部分结构研究

冷蒿(Artemisia frigida)挥发性有机化合物(volatile organic compounds, VOCs)具有特殊气味, 在植物受损伤时, 此气味会更加浓烈。该文通过对未损伤与损伤冷蒿VOCs成分分析、地上部分结构观察, 初步揭示了冷蒿VOCs释放与结构之间的关系。结果表明, 未损伤冷蒿VOCs主要含有22种化合物, 其主要成分是莰烯(14.27%)、(E)-乙酸-3-己烯酯(10.85%)、对-伞花烃(9.05%)、桉树脑(39.80%)、α-萜品醇(10.04%)、β-萜品醇(2.48%)、樟脑(5.66%)和(R)-(-)-对薄荷-1-烯-4-醇(3.84%)。损伤较未损伤冷蒿VOCs增加了12种物质, 其中相对含量大于1%的化合物分别为顺-3-己烯醛(1.15%)、2-己烯醛(1.34%)、顺-牻牛儿醇(2.66%)、冰片(4.47%)、(1R,4R)(+)-对-薄荷-2,8-二烯(9.15%)、乙酸冰片酯(1.37%)和4(14), 11-桉叶双烯(1.30%)。冷蒿叶片中栅栏组织发达, 叶柄内具有2-3处栅栏组织, 并且栅栏组织中都具有发达的气室, 同时气室与气孔相连。因此, 损伤较未损伤冷蒿VOCs种类和浓度增多的原因可能为: 冷蒿VOCs合成后大量储存于气室中, 当叶片损伤时, VOCs大量释放出来, 同时合成释放一些新的VOCs, 致使损伤冷蒿VOCs种类和浓度增加。     

Petrol exhaust pollution impairs honey bee learning and memory

Volatile organic compounds (VOCs) serve as important infochemicals, mediating several ecological interactions including herbivory and pollination. Atmospheric pollutants including traffic‐related air pollution may impair the detection of VOCs used by insects in insect–plant interactions. We investigated the indirect effect of petrol exhaust pollution on olfactory learning and memory (short and long term) in honey bees. Using appetitive olfactory conditioning, we trained bees to learn one of four floral VOC profiles; linalool, dipentene, myrcene and geranium. VOCs were unpolluted or polluted with exhaust collected from a petrol generator. Exhaust emissions included concentrations of CO (246.07 + 17 ppm), NO (20.50 + 6.90 ppb) and NO2 (20.93 + 0.05 ppb) consistent with those typically encountered in urban areas and near roads. Once bees had learnt the training VOC, we tested whether they could recognise that VOC 1 h, 24 h and 48 h post‐training. Bees took significantly longer to learn polluted VOCs and forgot them faster than unpolluted ones. We also tested the ‘masking’ potential of pollution on floral VOCs. Using gas chromatography mass spectroscopy we noted differences in the chemical profile of polluted versus unpolluted VOCs and tested whether bees could recognise polluted VOCs if trained using unpolluted ones. For several VOCs tested, bees could distinguish between polluted and unpolluted VOCs. Ultimately, our results show that air pollution changes the recognition and retention of floral VOCs by bees which may consequently impact foraging efficiency.     

Removal of volatile organic compounds by natural materials during composting of poultry litter

The objective of this study was to reduce volatile organic compounds (VOCs) produced during composting of poultry litter. The natural zeolite, expanded perlite, pumice and expanded vermiculite as the natural materials were used for the reducing of VOCs. Composting was performed in a laboratory scale in-vessel composting plant. Poultry litter was composted for 100 d with volumetric ratio of natural materials:poultry litter of 1:10. The VOCs were tested using the FT-IR method by VOCs analyzer. Studies showed that VOCs generation was the greatest in the control treatment without any natural materials. The natural materials significantly reduced VOCs. At the end of the processes, removal efficiency was 79.73% for NZ treatment, 54.59% for EP treatment, 88.22% for P treatment and 61.53% for EV treatment. Potential of removal for VOCs on poultry litter matrix using natural materials was in order of: P>NZ>EV>EP.     

The scent of disease: volatile organic compounds of the human body related to disease and disorder

Hundreds of volatile organic compounds (VOCs) are emitted from the human body, and the components of VOCs usually reflect the metabolic condition of an individual. Therefore, contracting an infectious or metabolic disease often results in a change in body odour. Recent progresses in analytical techniques allow rapid analyses of VOCs derived from breath, blood, skin and urine. Disease-specific VOCs can be used as diagnostic olfactory biomarkers of infectious diseases, metabolic diseases, genetic disorders and other kinds of diseases. Elucidation of pathophysiological mechanisms underlying production of disease-specific VOCs may provide novel insights into therapeutic approaches for treatments for various diseases. This review summarizes the current knowledge on chemical and clinical aspects of body-derived VOCs, and provides a brief outlook at the future of olfactory diagnosis.     

Biofiltration of composting gases using different municipal solid waste-pruning residue composts: monitoring by using an electronic nose

The concentration of volatile organic compounds (VOCs) during the composting of kitchen waste and pruning residues, and the abatement of VOCs by different compost biofilters was studied. VOCs removal efficiencies greater than 90% were obtained using composts of municipal solid waste (MSW) or MSW-pruning residue as biofilter material. An electronic nose identified qualitative differences among the biofilter output gases at very low concentrations of VOCs. These differences were related to compost constituents, compost particle size (2-7 or 7-20 mm), and a combination of both factors. The total concentration of VOCs determined by a photoionization analyser and inferred from electronic nose data sets were correlated over an ample range of concentrations of VOCs, showing that these techniques could be specially adapted for the monitoring of these processes.     

挥发性有机化合物(VOCs)对IVF实验室影响的研究进展

体外受精-胚胎移植技术已成为当今治疗不育症的主要手段,为取得令人满意的临床妊娠率,体外受精(IVF)实验室的空气质量控制成为生殖助孕工作者关注的重点。胚胎培养室的挥发性有机化合物(volatileorganiccompounds,VOCs)含量对配子-胚胎发育的影响至关重要,体外胚胎对VOCs的耐受能力差,其含量超过一定界限时则会对配子和胚胎造成影响。本文概述了IVF实验室VOCs的来源,VOCs的生殖毒性,VOCs的测定方法以及胚胎培养室内VOCs的控制途径等,旨在更严格的进行IVF实验室的空气质量控制,尽可能杜绝VOCs的污染,提高IVF的成功率。     

微生物源挥发性物质防治采后果蔬病害的研究进展

随着化学杀菌剂弊端的日益凸显,生物防治已逐渐成为采后果蔬病害控制的研究和开发热点.其中,很多微生物产生的多种挥发性物质(volatile organic compounds,VOCs),能显著抑制多种病原菌的生长繁殖,有效控制采后果蔬病害.由于微生物源VOCs具有有效、安全、环保、易降解和无残留等优点,越来越受到各国研...     

Sites of synthesis,biochemistry and functional role of plant volatiles

All plants are able to emit volatile organic compounds (VOCs) and the content and composition of these molecules show both genotypic variation and phenotypic plasticity. VOCs are involved in plant–plant interactions and for the attraction of pollinating and predatory insects. The biochemistry and molecular biology of plant VOCs is vast and complex, including several biochemical pathways and hundreds of genes. In this review the site of synthesis, the biosynthesis and the functional role of VOCs are discussed.     

Volatile Organic Compounds and Their Roles in Bacteriostasis in Five Conifer Species

In order to make clear the functions of plant volatile organic compounds (VOCs) on bacteriostasis and air decontamination, we analyzed the composition and content of VOCs in Pinus tabulaeformis Carr., P. bungeana Zucc., Sabina chinensis Antoine, Picea koraiensis Nakai, and Cedrus deodara G. Don under near-natural conditions using the thermal-desorption cold trap gas chromatography/mass spectrometer technique. The effects of the VOCs on airborne microorganisms were investigated using the method of natural sedimentation. Results showed that the major VOCs were as follows: limonene, β-pinene, α-pinene,and α-caryophyllene in Pinus tabulaeformis and P. bungeana; limonene, borneol acetate, β-pinene, myrcene, and tricylene in S. chinensis; limonene, α-pinene, myrcene, camphene, and β-pinene in Picea koraiensis; and limonene, 2, (10)-pinene, α-pinene, and myrcene in C. deodara. These VOCs and the corresponding foliar extracts inhibited the growth of bacteria and stimulated the growth of fungi. Experimental data using monomers of the VOCs demonstrated that limonene, β-pinene, and three aldehydes could significantly inhibit bacterial growth, suggesting an inhibitory effect of VOCs on the growth of airborne microorganisms in the five conifer species. The bacteriostasis and air-decontaminating effects of plant VOCs are further discussed in terms of their chemical composition.     

Fungal volatile organic compounds: A review with emphasis on their biotechnological potential

Fungi produce various mixtures of gas-phase, carbon-based compounds called volatile organic compounds (VOCs) that due to their small size are able to diffuse through the atmosphere and soils. Despite some methodological and technological constraints, researchers have detected and characterized approximately 250 fungal VOCs, many of which have characteristic odors and are produced during primary and secondary metabolism. Fungal VOCs may contribute to a controversial medical diagnosis called “sick building syndrome” and may also be important in the success of some biocontrol species of Trichoderma. VOCs also play important signaling roles for fungi in their natural environments. Many ecological interactions are mediated by VOCs, including those between fungi and plants, arthropods, bacteria, and other fungi. The diverse functions of fungal VOCs can be developed for use in biotechnological applications for biofuel, biocontrol, and mycofumigation. Volatiles represent a new frontier in bioprospecting, and the study of these gas-phase compounds promises the discovery of new products for human exploitation and will generate new hypotheses in fundamental biology.     

受害兴安落叶松挥发物混合物对林间昆虫的诱集

植株释放的挥发物能够调节寄主、害虫及天敌三者关系,是植物与害虫协同进化的产物。兴安落叶松挥发物种类虽已确定,但这些物质,特别是受害植株所释放的挥发物对林间昆虫的影响尚不清楚。本研究在3种林龄林分内设置携带受害兴安落叶松枝叶挥发物的诱捕器以考察其对林间昆虫的影响。结果表明挥发物混合物对昆虫诱集效果良好,特别是对天牛类及叶甲类。林龄并未对挥发物的引诱效果造成显著影响,可能与本研究年龄组的划分标准有关。文章指出应将诱集昆虫群落进一步细化,并对关键种或类群进行电生理方面的深入探讨。本文也指出了受害兴安落叶松挥发物混合物发展为植物源农药的前景。     

Biomimicry of volatile‐based microbial control for managing emerging fungal pathogens

Volatile organic compounds (VOCs) are known to be produced by a wide range of micro‐organisms and for a number of purposes. Volatile‐based microbial inhibition in environments such as soil is well‐founded, with numerous antimicrobial VOCs having been identified. Inhibitory VOCs are of interest as microbial control agents, as low concentrations of gaseous VOCs can elicit significant antimicrobial effects. Volatile organic compounds are organic chemicals typically characterized as having low molecular weight, low solubility in water, and high vapour pressure. Consequently, VOCs readily evaporate to the gaseous phase at standard temperature and pressure. This contact‐independent antagonism presents unique advantages over traditional, contact‐dependent microbial control methods, including increased surface exposure and reduced environmental persistence. This approach has been the focus of our recent research, with positive results suggesting it may be particularly promising for the management of emerging fungal pathogens, such as the causative agents of white‐nose syndrome of bats and snake fungal disease, which are difficult or impossible to treat using traditional approaches. Here, we review the history of volatile‐based microbial control, discuss recent progress in formulations that mimic naturally antagonistic VOCs, outline the development of a novel treatment device, and highlight areas where further work is needed to successfully deploy VOCs against existing and emerging fungal pathogens.     

Harnessing endophytes for industrial microbiology

Endophytic microorganisms exist within the living tissues of most plant species. They are most abundant in rainforest plants. Novel endophytes usually have associated with them novel secondary natural products and/or processes. Muscodor is a novel endophytic fungal genus that produces bioactive volatile organic compounds (VOCs). This fungus, as well as its VOCs, has enormous potential for uses in agriculture, industry and medicine. Muscodor albus produces a mixture of VOCs that act synergistically to kill a wide variety of plant and human pathogenic fungi and bacteria. This mixture of gases consists primarily of various alcohols, acids, esters, ketones and lipids. Artificial mixtures of the VOCs mimic the biological effects of the fungal VOCs when tested against a wide range of fungal and bacterial pathogens. Many practical applications for 'mycofumigation' by M. albus have been investigated and the fungus is now in the market place.     

The volatile organic compounds from the mycelium of Tuber borchii Vitt

The mycelium of T. borchii (characterized by DNA analysis) grown in sterile liquid medium produced some VOCs. The VOCs were retained on carbographs by passing a flow of helium, isolated and characterized in a GC-MS equipment after a thermal desorption. The compounds present in the VOCs from the mycelium cultures, but not in the VOCs from the control cultures, contained 29 compounds. The main compounds were 1,3-ditertbutylbenzene (16.1 ng/l), 3-methylheptane (9.2 ng/l), butan-2-one (8.8 ng/l), ethynylbenzene (5.6 ng/l), and octan-3-one (4.9 ng/l).     

Production of volatile organic compounds by an antagonistic strain Paenibacillus polymyxa WR-2 in the presence of root exudates and organic fertilizer and their antifungal activity against Fusarium oxysporum f. sp. niveum

The volatile organic compounds (VOCs) produced by antagonistic microbes have great antifungal potential against soil-borne fungal pathogens. The VOCs produced by Paenibacillus polymyxa strain WR-2 in the presence of root exudates and organic fertilizer were identified and their effects on the growth and spore germination of Fusarium oxysporum f. sp. niveum were evaluated. The VOCs produced by WR-2 inhibited the growth of F. oxysporum by 38%, 36% and 40% in agar medium, sterilized soil and natural soil, respectively. This inhibitory effect was increased to 60%, 58% and 64% with the addition of organic fertilizer in agar medium, sterilized soil and natural soil, respectively. The addition of root exudates did not affect the production of antifungal VOCs by WR-2. The VOCs produced by WR-2 completely inhibited the germination of F. oxysporum spores. Out of 42 identified VOCs, seven VOCs; benzothiazole, benzaldehyde, undecanal, dodecanal, hexadecanal, 2-tridecanone and phenol were found to inhibit the growth of F. oxysporum. The results of these experiments suggest another significance of using organic fertilizer as a carrier material with the biocontrol agents to control soil-borne fungal pathogens.     

NaNO3胁迫对两种微囊藻VOCs释放的影响

为了揭示硝酸盐过量积累对藻类产生胁迫后对藻类挥发性有机化合物(VOCs)释放以及水体气味的影响, 研究以形成蓝藻水华的主要种类铜绿微囊藻和水华微囊藻为材料, 在NaNO3胁迫下, 对其细胞生长和释放的VOCs进行测定分析。结果表明, NaNO3胁迫24h后, 铜绿微囊藻和水华微囊藻细胞生长均受到明显影响, 与对照相比细胞密度分别降低了29.6%和43.0%。在正常条件下, 铜绿微囊藻和水华微囊藻分别释放出26和27种化合物, 其主要类型是硫化物、烃类、萜烯类、苯类、醛类和酯类化合物。在NaNO3胁迫下, VOCs含量均明显增加, 其中铜绿微囊藻释放的此6类VOCs含量分别增加了60.5%、14.3%、136.6%、92.1%、730.0%和120.7%, 水华微囊分别增加了172.7%、162.5%、154.0%、55.9%、51.2%和109.4%。此外, 铜绿微囊藻VOCs中出现4种新成分, 水华微囊藻VOCs中出现1种新成分。由此可见, 硝酸盐过量积累对藻细胞产生胁迫后会诱导其释放出大量VOCs, 从而增加水体气味、破坏水质。