白蚁表皮碳氢化合物研究进展

近年来, 固相微萃取等现代技术的使用显著促进了白蚁表皮碳氢化合物研究的开展。至今, 已有约29种白蚁的表皮碳氢化合物组分得到鉴定, 分属于木白蚁科、 鼻白蚁科、 原白蚁科和白蚁科, 其组分主要为正烷烃、 含有不同数量甲基的支链烷烃及少量烯烃。白蚁表皮碳氢化合物不仅具有一定的科、 属特异性, 大多数种类还具备特有组分, 表明其可作为种间识别的指标。表皮碳氢化合物组分在种内个体识别方面的作用, 在低等白蚁中多获得了支持性结果, 但也有研究认为在这些种类中表皮碳氢化合物不是种内个体识别（同巢个体识别）的唯一指标。发现其与品级分化的相关是近年来白蚁表皮碳氢化合物研究的重要进展。有些种类表皮碳氢化合物的年消长与生殖蚁的分化有关; 而另一些种类生殖蚁含有表皮碳氢化合物特有组分, 其含量与生殖蚁的生殖状态有关, 提示其可能在品级分化中发挥重要作用。作为研究白蚁品级分化和维持机理的新方向, 表皮碳氢化合物值得进一步研究探索。     

Short-term phenotypic plasticity in long-chain cuticular hydrocarbons

Cuticular hydrocarbons provide arthropods with the chemical equivalent of the visually extravagant plumage of birds. Their long chain length, together with the number and variety of positions in which methyl branches and double bonds occur, provide cuticular hydrocarbons with an extraordinary level of information content. Here, we demonstrate phenotypic plasticity in an individual's cuticular hydrocarbon profile. Using solid-phase microextraction, a chemical technique that enables multiple sampling of the same individual, we monitor short-term changes in cuticular hydrocarbon profiles of individual crickets, Teleogryllus oceanicus, in response to a social challenge. We experimentally manipulate the dominance status of males and find that dominant males, on losing fights with other dominant males, change their hydrocarbon profile to more closely resemble that of a subordinate. This result demonstrates that cuticular hydrocarbons can be far more responsive to changes in social dominance than previously realized.     

Development changes of cuticular hydrocarbons in Chrysomya rufifacies larvae: potential for determining larval age

Age determination is the basis of determining the postmortem interval using necrophagous fly larvae. To explore the potential of using cuticular hydrocarbons for determining the ages of fly larvae, changes of cuticular hydrocarbons in developing larvae of Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) were investigated using gas chromatography with flame-ionization detection and gas chromatography-mass spectrometry. This study showed that the larvae produced cuticular hydrocarbons typical of insects. Most of the hydrocarbons identified were alkanes with the carbon chain length of 21-31, plus six kinds of alkenes. The hydrocarbon composition of the larvae correlated with age. The statistical results showed that simple peak ratios of n-C29 divided by another eight selected peaks increased significantly with age; their relationships with age could be modelled using exponential or power functions with R(2) close to or > 0.80. These results suggest that cuticular hydrocarbon composition is a useful indicator for determining the age of larval C. rufifacies, especially for post-feeding larvae, which are difficult to differentiate by morphology.     

Learning and perceptual similarity among cuticular hydrocarbons in ants

Nestmate recognition in ants is based on perceived differences in a multi-component blend of hydrocarbons that are present on the insect cuticle. Although supplementation experiments have shown that some classes of hydrocarbons, such as methyl branched alkanes and alkenes, have a salient role in nestmate recognition, there was basically no information available on how ants detect and perceive these molecules. We used a new conditioning procedure to investigate whether individual carpenter ants could associate a given hydrocarbon (linear or methyl-branched alkane) to sugar reward. We then studied perceptual similarity between a hydrocarbon previously associated with sugar and a novel hydrocarbon. Ants learnt all hydrocarbon-reward associations rapidly and with the same efficiency, regardless of the structure of the molecules. Ants could discriminate among a large number of pairs of hydrocarbons, but also generalised. Generalisation depended both on the structure of the molecule and the animal's experience. For linear alkanes, generalisation was observed when the novel molecule was smaller than the conditioned one. Generalisation between pairs of methyl-alkanes was high, while generalisation between hydrocarbons that differed in the presence or absence of a methyl group was low, suggesting that chain length and functional group might be coded independently by the ant olfactory system. Understanding variations in perception of recognition cues in ants is necessary for the general understanding of the mechanisms involved in social recognition processes based on chemical cues.     

Long-term stability of hornet cuticular hydrocarbons facilitates chemotaxonomy using museum specimens

Cuticular hydrocarbons are key compounds used for insect chemical communication and their species-specificity makes them of great utility to chemotaxonomists. However, very little is known about their long-term stability in relation to their use as reliable taxonomic tools. We compared the cuticular hydrocarbon profiles of fresh extracts from four hornet ( Vespa ) species with extracts from specimens that were frozen for 1 year and of those stored in insect display boxes for 20 years. Cuticular hydrocarbon profiles were qualitatively very stable, maintaining their species-specific profiles even after 20 years. The long-term stability of cuticular hydrocarbons in hymenopterans opens up the possibility of using museum collections for chemotaxonomy studies and helping with the delineation of species in difficult groups.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 732–737.     

甲虫表皮碳氢化合物研究进展

昆虫表皮碳氢化合物(cuticular hydrocarbons)是正烷烃、不饱和烃以及甲基支链烃的混合物.除了保持水分的基本功能外,还具有多种生物功能.鞘翅目昆虫(俗称甲虫)是多样性最为丰富的昆虫类群,目前对其表皮碳氢化合物研究开展颇多,主要见于化学通讯领域,内容涉及到性信息素、标记信息素、聚集信息素、化学拟态、寄主...     

Characterization and discrimination of three Rhopalosiphum species (Homoptera: aphididae) using cuticular hydrocarbons and cuticular surface patterns

• 1.1. Cuticular hydrocarbons of two clones of Rhopalosiphum maidis, two of R. padi, one of R. insertum, and one of Schizaphis graminum were identified as n-alkanes, monomethylalkanes and dimethylalkanes.
• 2.2. No qualitative differences in hydrocarbon content were apparent among the six aphid populations studied; however, hydrocarbon profiles were discriminatory.
• 3.3. Discriminant analysis of the proportions of the cuticular hydrocarbons selected 29 hydrocarbon components that provided discrimination among populations except for the two R. padi clones which were indistinguishable.
• 4.4. Scanning electron micrographs showed very clear differences in the cuticular surface patterns among the three Rhopalosiphum species.

     

Diverse cuticular hydrocarbons from Australian canebeetles (Coleoptera: Scarabaeidae)

Abstract  Cuticular hydrocarbon components in beetles of six Australian melolonthines whose larvae damage sugarcane, Antitrogus parvulus (Britton), A. consanguineus (Blackburn), Lepidiota negatoria (Blackburn), L. picticollis (Lea), L. noxia (Britton) and Dermolepida alborhirtum (Arrow), are identified and compared. These species demonstrate species-specific cuticular hydrocarbon profiles with a number of unprecedented structures. Major components have been identified as polymethylated hydrocarbons, 3-methyl substituted n -alkanes, 9,10-allenes and the corresponding C9 alkenes. The similarity of these compounds shows some correlation with the phylogeny of the beetles, but two polymethylated C₂₂ hydrocarbons are unique to A. parvulus. One C₂₅ allene is shown to have a potential role in mate recognition in A. consanguineus.     

Learning and discrimination of cuticular hydrocarbons in a social insect

Social insect cuticular hydrocarbon (CHC) mixtures are among the most complex chemical cues known and are important in nest-mate, caste and species recognition. Despite our growing knowledge of the nature of these cues, we have very little insight into how social insects actually perceive and discriminate among these chemicals. In this study, we use the newly developed technique of differential olfactory conditioning to pure, custom-designed synthetic colony odours to analyse signal discrimination in Argentine ants, Linepithema humile. Our results show that tri-methyl alkanes are more easily learned than single-methyl or straight-chain alkanes. In addition, we reveal that Argentine ants can discriminate between hydrocarbons with different branching patterns and the same chain length, but not always between hydrocarbons with the same branching patterns but different chain length. Our data thus show that biochemical characteristics influence those compounds that ants can discriminate between, and which thus potentially play a role in chemical signalling and nest-mate recognition.     

Correlation between mandibular gland secretion and cuticular hydrocarbons in the stingless bee Melipona quadrifasciata

We investigated whether Melipona quadrifasciata worker mandibular gland secretions contribute directly to their cuticular hydrocarbon profile. The mandibular gland secretion composition and cuticular surface compounds of newly emerged worker bees, nurse bees, and foragers were determined by gas chromatography and mass spectrometry and compared. Both the mandibular gland secretions and the cuticular surface compounds of all worker stages were found to be composed almost exclusively of hydrocarbons. Although the relative proportion of hydrocarbons from the cuticular surface and gland secretion was statistically different, there was a high similarity in the qualitative composition between these structures in all groups of bees.     

Intraspecific variation in the cuticular hydrocarbons of the sandfly Phlebotomus perfiliewi from Italy

The cuticular hydrocarbons of Phlebotomus perfiliewi Parrot from representative localities on both sides of Italy show contrasts which support the view of Ward et al., (1981) that there are distinguishable populations of this sandfly on the Adriatic and Tyrrhenian coasts. It is suggested that the Appennine mountains form a barrier between the Adriatic and Tyrrhenian populations. A third distinct hydrocarbon type of P. perfiliewi was detected in Calabria, southern Italy, where contact between the Adriatic and Tyrrhenian types of flies is most likely to occur. P. perfiliewi from a trans-Appennine pass were also of the Calabrian hydrocarbon type. These hydrocarbon contrasts between allopatric populations of P. perfiliewi may result from clinical variation across the Appennines, associated with different host preferences, or they may represent apomictic populations with differential mate recognition systems.     

白蚁表皮碳氢化合物组分鉴定及分类学意义

应用GC-MS分析表明,不同种类白蚁表皮碳氢化合物组成和含量均有差异。运用UPGMA聚合R分析的最小距离系数值绘制的系统树表明：圆唇凸额类白蚁——黄胸散白蚁Reticulitermes flaviceps、双色散白蚁R. dichrous和R. sp.1之间;圆唇平额类白蚁——圆唇散白蚁R. labralis、小头散白蚁R. microcephalus、R. sp.2和R. sp.3之间; 尖唇类白蚁——海南异白蚁Heterotermes hainanensis、拧黄异白蚁H. citrinus、细颚异白蚁H.leptomandibularis、尖唇异白蚁H. aculabialis和H. sp. 4之间的亲缘关系较近。3类白蚁中,圆唇凸额类白蚁和圆唇平额类白蚁亲缘关系相近,而两者与尖唇类白蚁亲缘关系较远。实验结果表明,我国存在异白蚁属,它与散白蚁属主要区别在于其表皮缺乏以下数种碳氢化合物：正十七烷烃、正二十烷烃、正二十一烷烃、正二十二烷烃、正二十三烷烃、正二十四烷烃和正二十六烷烃等;却含有一种特殊化合物异喹啉。表皮碳氢化合物分析的结果与形态分类的结果有一定差异,形态分类被鉴定为双色散白蚁的R. sp.1,被鉴定为小头散白蚁的R. sp.2,被鉴定为圆唇散白蚁的R.sp.3,被鉴定为尖唇散白蚁的H. sp.4,根据表皮碳氢化合物分析的结果,R. sp.1、R. sp.3和H. sp.4可能是其他种,而R. sp.2则可能是圆唇散白蚁的亚种或其他种。     

Crickets detect the genetic similarity of mating partners via cuticular hydrocarbons

Animals should decipher information about the genetic make‐up of conspecifics in order to enhance the fitness benefits associated with mate choice. Although there is increasing evidence to suggest that animals make genetically informed decisions about their mating partners, we understand relatively little about the sensory mechanisms informing these decisions. Here, we investigate whether cuticular hydrocarbons, chemical compounds found on the cuticle of most terrestrial arthropods, provide a means of discerning genetic similarity during mate choice in the cricket, Teleogryllus oceanicus. We found that individuals preferentially mated with partners who share more dissimilar cuticular hydrocarbon profiles and that similarity in cuticular hydrocarbon profiles between mating pairs correlated with their genetic similarity. Our results provide good evidence that cuticular hydrocarbon profiles offer a means of assessing genetic compatibility in T. oceanicus, enabling individuals to choose their most genetically suitable mate.     

Task-related variation of postpharyngeal and cuticular hydrocarbon compositions in the ant Myrmicaria eumenoides

In the ant Myrmicaria eumenoides we investigated postpharyngeal and cuticular hydrocarbons. At eclosion the glands contained almost no hydrocarbons and there were no lipid inclusions in the glandular epithelium. During the first 3 weeks of adult life the amount of hydrocarbons in the gland increased until day 5, and then remained constant while the lipid content in the epithelium increased steadily. Intracolonial hydrocarbon compositions were not uniform. Compositions of post-pharyngeal and cuticular hydrocarbons in individual ants varied simultaneously, but in different manner depending on the tasks of the ant (brood-tenders, foragers, scouts). Variations on the cuticle were greater than in the gland, but they were strongly correlated. Independent of ants' age and task, cuticular hydrocarbon compositions were dominated by alkenes and alkadienes. Task-specific differences in cuticular compositions were mainly in the amount of alkenes (high in foragers) and alkadienes (high in brood-tenders). Variation of hydrocarbons was low in ants up to 10 weeks old. Thereafter, ants fell into two groups: (1) ants that did not change their hydrocarbons and remained in the nest, and (2) ants that changed their hydrocarbon compositions and became foragers. These results contribute to an ongoing discussion of the dynamic relationship between post-pharyngeal and cuticular hydrocarbons.     

Effects of allatectomy and ovariectomy on cuticular hydrocarbons in Calliphora vomitoria (diptera)

The relationships between female attractiveness, cuticular hydrocarbons, and levels of juvenile hormone and ecdysteroids were studied in Calliphora vomitoria. The experiments were conducted at 48 and 72 h post-emergence, according to attractiveness appearance and increase. The 48-h-old allatectomized females were less attractive than the control females, whereas no changes occurred either in cuticular hydrocarbons total mass production or in the different hydrocarbon families. However, the 72-h-old allatectomized females were more attractive than the control females, and, in relative proportions, allatectomy led to an increase in monomethylalkanes and a decrease in n-alkanes. Only at 48 h were the ovariectomized females less attractive than the control females and did ovariectomy increase the relative proportions of monomethylalkanes. At 72 h, ovariectomy did not influence female attractiveness, but it decreased the total cuticular hydrocarbon production. Allatectomy and ovariectomy significantly decreased ecdysteroids levels at 48 and 72 h. Ovariectomy did not affect juvenile hormone production. These results suggest that attractiveness and cuticular hydrocarbon synthesis could be under the direct control of ecdysteroids and the indirect influence of juvenile hormone. © 1994 Wiley-Liss, Inc.     

Myrmecophilous aphids produce cuticular hydrocarbons that resemble those of their tending ants

Aphid-tending ants protect aphids from natural enemies and collect honeydew secreted by the aphids. However, ants also often prey on the aphids they attend. Aphids, therefore, like social parasites of ants, may well have evolved chemical mimicry as an anti-predation strategy. In this study, we aimed to determine whether the aphid Stomaphis yanonis actively produces cuticular hydrocarbons (CHCs) that resemble those of the tending ant Lasius fuji. In the wild, ants put their CHCs on the aphids that they are tending, so in this study we analyzed “ant-free” aphids. Mature aphids that exuviated in the absence of ant attendance had almost all of the hydrocarbon components that the ants’ CHCs had. Moreover, hydrocarbons artificially applied to the aphids’ body surface were lost by exuviation. Taken together, these findings indicate that mature aphids actively produced ant-like CHCs, and they constitute the first documentation of a chemical resemblance between aphids and ants in a specific aphid–ant association.     

The cuticular hydrocarbons of the Triatoma sordida species subcomplex (Hemiptera: Reduviidae)

The cuticular hydrocarbons of the Triatoma sordida subcomplex (Hemiptera: Reduviidae: Triatominae) were ana-lysed by gas chromatography and their structures identified by mass spectrometry. They comprised mostly n-alkanes and methyl-branched alkanes with one-four methyl substitutions. n-alkanes consisted of a homologous series from C21-C33 and represented 33-45% of the hydrocarbon fraction; n-C29 was the major component. Methyl-branched alkanes showed alkyl chains from C24-C43. High molecular weight dimethyl and trimethylalkanes (from C35-C39) represented most of the methyl-branched fraction. A few tetramethylalkanes were also detected, comprising mostly even-numbered chains. Several components such as odd-numbered 3-methylalkanes, dimethylalkanes and trimethylalkanes of C37 and C39 showed patterns of variation that allowed the differentiation of the species and populations studied. Triatoma guasayana and Triatoma patagonica showed the most distinct hydrocarbon patterns within the subcomplex. The T. sordida populations from Brazil and Argentina showed significantly different hydrocarbon profiles that posed concerns regarding the homogeneity of the species. Triatoma garciabesi had a more complex hydrocarbon pattern, but it shared some similarity with T. sordida. The quantitative and qualitative variations in the cuticular hydrocarbons may help to elucidate the relationships between species and populations of this insect group.     

Male-specific transfer and fine scale spatial differences of newly identified cuticular hydrocarbons and triacylglycerides in a Drosophila species pair

We analyzed epicuticular hydrocarbon variation in geographically isolated populations of D. mojavensis cultured on different rearing substrates and a sibling species, D. arizonae, with ultraviolet laser desorption/ionization mass spectrometry (UV-LDI MS). Different body parts, i.e. legs, proboscis, and abdomens, of both species showed qualitatively similar hydrocarbon profiles consisting mainly of long-chain monoenes, dienes, trienes, and tetraenes. However, D. arizonae had higher amounts of most hydrocarbons than D. mojavensis and females of both species exhibited greater hydrocarbon amounts than males. Hydrocarbon profiles of D. mojavensis populations were significantly influenced by sex and rearing substrates, and differed between body parts. Lab food-reared flies had lower amounts of most hydrocarbons than flies reared on fermenting cactus substrates. We discovered 48 male- and species-specific hydrocarbons ranging in size from C(22) to C(50) in the male anogenital region of both species, most not described before. These included several oxygen-containing hydrocarbons in addition to high intensity signals corresponding to putative triacylglycerides, amounts of which were influenced by larval rearing substrates. Some of these compounds were transferred to female cuticles in high amounts during copulation. This is the first study showing that triacylglycerides may be a separate class of courtship-related signaling molecules in drosophilids. This study also extends the kind and number of epicuticular hydrocarbons in these species and emphasizes the role of larval ecology in influencing amounts of these compounds, many of which mediate courtship success within and between species.     

西花蓟马表皮碳氢化合物成份分析

西花蓟马Frankliniella occidentalis(Pergande)是一种重要的世界性害虫。为了明确西花蓟马表皮碳氢化合物的主要成分,本文采用改进的进样技术,利用气相色谱-质谱联用仪(GC-MS)对西花蓟马成虫和若虫表皮碳氢化合物进行分析。经NIST数据库检索,并与标准图谱比较,应用色谱峰面积归一法测定各种成分及其相对含量,实验结果表明,西花蓟马成虫和若虫表皮中的主要成分为C25～C29的直链和支链饱和烷烃;成虫表皮中含有9种碳氢化合物,若虫表皮中有8种碳氢化合物;9-甲基二十五烷是其成虫特有的,其它8种碳氢化合物是成虫与若虫共有的,但其含量略有差异。     

Adaptation of coimmobilized Rhodococcus cells to oil hydrocarbons in a column bioreactor

A possible adaptation of the association of Rhodococcus ruber and Rhodococcus opacus strains immobilized on modified sawdust to oil hydrocarbons in a column bioreactor was investigated. In the bioreactor, the bacterial population showed higher hydrocarbon and antibiotic resistance accompanied by the changes in cell surface properties (hydrophobicity, electrokinetic potential) and in the content of cellular lipids and biosurfactants. The possibility of using adapted Rhodococcus strains for the purification of oil-polluted water in the bioreactor was demonstrated.