scholarly journals Chemical convergence between a guild of facultative myrmecophilous caterpillars and host plants

2020 ◽  
Author(s):  
Luan Dias Lima ◽  
José Roberto Trigo ◽  
Lucas Augusto Kaminski
Keyword(s):  
Cuticular Hydrocarbons ◽  
Host Plants ◽  
Similarity Index ◽  
Chemical Mimicry ◽  
Gas Chromatography Mass Spectrometry ◽  
List Type ◽  
Defensive Strategy ◽  
Chemical Camouflage ◽  
Multimodal Systems ◽  
Nectar Rewards

AbstractAnts exert a strong selective pressure on herbivorous insects, although some caterpillars can live in symbiosis with them using chemical defensive strategies.We investigated the adaptive resemblance of cuticular hydrocarbons (CHCs) in multitrophic systems involving a guild of facultative myrmecophilous caterpillar species (Lepidoptera: Lycaenidae), tending ants (Hymenoptera: Formicidae) and host plants from three families. We hypothesized that the CHCs of the caterpillars would resemble those of their host plants (chemical camouflage).We analyzed CHCs using gas chromatography/mass spectrometry. Morisita’s similarity index (SI) was used to compare CHC profiles of caterpillar species with different types of ant associations (commensal or mutualistic), ants and host plants.We found strong convergence between caterpillars’ CHCs and plants, especially for commensal species that do not provide secretion rewards for ants. Moreover, we found unexpected chemical convergence among mutualistic caterpillar species that offer nectar reward secretions to ants.These results show that the studied caterpillars acquire CHCs through their diet and that they vary according to host plant species and type of ant association (commensalism or mutualism). This ‘chemical camouflage’ of myrmecophilous caterpillars may have arisen as a defensive strategy allowing coexistence with ants on plants, whereas ‘chemical conspicuousness’ may have evolved in the context of honest signaling between true mutualistic partners.We suggest the existence of both Müllerian and Batesian chemical mimicry rings among myrmecophilous caterpillar species. Cuticular chemical mixtures can play a key adaptive role in decreasing ant attacks and increasing caterpillar survival in multimodal systems.Graphical abstractChemical camouflage can be a defensive strategy of myrmecophilous caterpillars against ants.‘Chemical conspicuousness’ is proposed as a new strategy mediated by cuticular hydrocarbons in myrmecophilous caterpillars.Chemical mimicry rings can occur between myrmecophilous caterpillars and especially between mutualistic species that produce nectar rewards for ants.

scholarly journals Odor-active volatile compounds in preterm breastmilk

2021 ◽  
Author(s):  
Mariana Muelbert ◽  
Laura Galante ◽  
Tanith Alexander ◽  
Jane E. Harding ◽  
Chris Pook ◽  
...  
Keyword(s):  
Gestational Diabetes ◽  
Volatile Compounds ◽  
Solid Phase ◽  
Relative Concentration ◽  
Gas Chromatography Mass Spectrometry ◽  
List Type ◽  
Maternal Characteristics ◽  
Medium Chain ◽  
Lactation Stage ◽  
Cephalic Phase

Abstract Background Volatile compounds in breastmilk (BM) likely influence flavor learning and, through the cephalic phase response, metabolism, and digestion. Little is known about the volatile compounds present in preterm BM. We investigated whether maternal or infant characteristics are associated with the profile of volatile compounds in preterm BM. Methods Using solid-phase microextraction coupled with gas chromatography/mass spectrometry, we analyzed volatile compounds in 400 BM samples collected from 170 mothers of preterm infants. Results Forty volatile compounds were detected, mostly fatty acids and their esters (FA and FAe), volatile organic compounds (VOCs), aldehydes, terpenoids, alcohols, and ketones. The relative concentration of most FA and FAe increased with advancing lactation and were lower in BM of most socially deprived mothers and those with gestational diabetes (p < 0.05), but medium-chain FAs were higher in colostrum compared to transitional BM (p < 0.001). Infant sex, gestational age, and size at birth were not associated with the profile of volatile compounds in preterm BM. Conclusions Sensory-active volatile FA and FAe are the major contributors to the smell of preterm BM. The associations between lactation stage, maternal characteristics, and volatile compounds, and whether differences in volatile compounds may affect feeding behavior or metabolism, requires further research. Impact Sensory-active volatile FAs are major contributors to the smell of preterm BM and are influenced by the lactation stage and maternal characteristics. Longitudinal analysis of volatile compounds in preterm BM found that FAs increased with advancing lactation. Colostrum had a higher concentration of medium-chain FAs compared to transitional BM and the concentration of these is associated with socioeconomic status, gestational diabetes, and ethnicity.

scholarly journals Urinary steroid profiling in diagnostic evaluation of an unusual adrenal mass

2019 ◽  
Vol 2019 ◽  
Author(s):  
N F Lenders ◽  
J R Greenfield
Keyword(s):  
Sensitivity And Specificity ◽  
Serum Biochemistry ◽  
Diagnostic Evaluation ◽  
Gas Chromatography Mass Spectrometry ◽  
List Type ◽  
Steroid Profiling ◽  
Rare Tumours ◽  
Adrenal Masses ◽  
Urinary Steroid

Summary Adrenal oncocytomas are rare tumours, with only approximately 160 cases reported in the literature. We report the use of urinary steroid profiling as part of their diagnostic evaluation and prognostication. A 45-year-old woman presented with clinical features of hyperandrogenism. Serum biochemistry confirmed androgen excess and computed tomography (CT) demonstrated a 3.2 cm adrenal tumour with density 39 HU pre-contrast. Urine steroid profiling showed elevated tetrahydro-11 deoxycortisol (THS), which is associated with adrenal malignancy. Laparoscopic adrenalectomy was performed, and histopathology diagnosed adrenal oncocytoma. Serum and urinary biochemistry resolved post-operatively and remained normal at 1-year follow-up. Learning points: Differential diagnosis of adrenal masses is challenging. Current techniques for differentiating between tumour types lack sensitivity and specificity. 24-h urinary steroid profiling is a useful tool for reflecting steroid output from adrenal glands. Gas chromatography-mass spectrometry (GC-MS) of urinary steroid metabolites has sensitivity and specificity of 90% for diagnosing adrenocortical carcinoma. Adrenal oncocytoma are rare tumours. Differentiating between benign and malignant types is difficult. Data guiding prognostication and management are sparse.

scholarly journals Preliminary Study on the Differences in Hydrocarbons Between Phosphine-Susceptible and -Resistant Strains of Rhyzopertha dominica (Fabricius) and Tribolium castaneum (Herbst) Using Direct Immersion Solid-Phase Microextraction Coupled with GC-MS

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1565
Author(s):  
Ihab Alnajim ◽  
Manjree Agarwal ◽  
Tao Liu ◽  
Beibei Li ◽  
Xin Du ◽  
...  
Keyword(s):  
Cuticular Hydrocarbons ◽  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Rhyzopertha Dominica ◽  
Gas Chromatography Mass Spectrometry ◽  
Stored Grain ◽  
Phosphine Resistance ◽  
Significant Difference ◽  
Resistant Strains ◽  
Direct Immersion

Phosphine resistance is a worldwide issue threatening the grain industry. The cuticles of insects are covered with a layer of lipids, which protect insect bodies from the harmful effects of pesticides. The main components of the cuticular lipids are hydrocarbon compounds. In this research, phosphine-resistant and -susceptible strains of two main stored-grain insects, T. castaneum and R. dominica, were tested to determine the possible role of their cuticular hydrocarbons in phosphine resistance. Direct immersion solid-phase microextraction followed by gas chromatography-mass spectrometry (GC-MS) was applied to extract and analyze the cuticular hydrocarbons. The results showed significant differences between the resistant and susceptible strains regarding the cuticular hydrocarbons that were investigated. The resistant insects of both species contained higher amounts than the susceptible insects for the majority of the hydrocarbons, sixteen from cuticular extraction and nineteen from the homogenized body extraction for T. castaneum and eighteen from cuticular extraction and twenty-one from the homogenized body extraction for R. dominica. 3-methylnonacosane and 2-methylheptacosane had the highest significant difference between the susceptible and resistant strains of T. castaneum from the cuticle and the homogenized body, respectively. Unknown5 from the cuticle and 3-methylhentriacontane from the homogenized body recorded the highest significant differences in R. dominica. The higher hydrocarbon content is a key factor in eliminating phosphine from entering resistant insect bodies, acting as a barrier between insects and the surrounding phosphine environment.

scholarly journals Cuticular hydrocarbons for identifying Sarcophagidae (Diptera)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hannah E. Moore ◽  
Martin J. R. Hall ◽  
Falko P. Drijfhout ◽  
Robert B. Cody ◽  
Daniel Whitmore
Keyword(s):  
Cuticular Hydrocarbons ◽  
Gas Chromatography Mass Spectrometry ◽  
Sexually Dimorphic ◽  
Adult Males ◽  
History Museum ◽  
Chemical Profiles ◽  
Males And Females ◽  
Species Specific ◽  
Flesh Flies ◽  
Eleven Species

AbstractThe composition and quantity of insect cuticular hydrocarbons (CHCs) can be species-specific as well as sexually dimorphic within species. CHC analysis has been previously used for identification and ageing purposes for several insect orders including true flies (Diptera). Here, we analysed the CHC chemical profiles of adult males and females of eleven species of flesh flies belonging to the genus Sarcophaga Meigen (Sarcophagidae), namely Sarcophaga africa (Wiedemann), S. agnata Rondani, S. argyrostoma Robineau-Desvoidy, S. carnaria (Linnaeus), S. crassipalpis Macquart, S. melanura Meigen, S. pumila Meigen, S. teretirostris Pandellé, S. subvicina Rohdendorf, S. vagans Meigen and S. variegata (Scopoli). Cuticular hydrocarbons extracted from pinned specimens from the collections of the Natural History Museum, London using a customised extraction technique were analysed using Gas Chromatography–Mass Spectrometry. Time of preservation prior to extraction ranged between a few weeks to over one hundred years. CHC profiles (1) allowed reliable identification of a large majority of specimens, (2) differed between males and females of the same species, (3) reliably associated males and females of the same species, provided sufficient replicates (up to 10) of each sex were analysed, and (4) identified specimens preserved for up to over one hundred years prior to extraction.

Chemical Mimicry as an Integrating Mechanism: Cuticular Hydrocarbons of a Termitophile and Its Host

Science ◽  
1980 ◽  
Vol 210 (4468) ◽  
pp. 431-433 ◽  
Author(s):  
R. W. HOWARD ◽  
C. A. MCDANIEL ◽  
G. J. BLOMQUIST
Keyword(s):  
Cuticular Hydrocarbons ◽  
Chemical Mimicry

scholarly journals Striking cuticular hydrocarbon dimorphism in the mason wasp Odynerus spinipes and its possible evolutionary cause (Hymenoptera: Chrysididae, Vespidae)

2015 ◽  
Vol 282 (1821) ◽  
pp. 20151777 ◽  
Author(s):  
Mareike Wurdack ◽  
Sina Herbertz ◽  
Daniel Dowling ◽  
Johannes Kroiss ◽  
Erhard Strohm ◽  
...  
Keyword(s):  
Cuticular Hydrocarbons ◽  
Cuticular Hydrocarbon ◽  
Chemical Mimicry ◽  
Host Organism ◽  
Wasp Species ◽  
The Third ◽  
Oviposition Strategy ◽  
Food Provision ◽  
The Impact

Cleptoparasitic wasps and bees smuggle their eggs into the nest of a host organism. Here the larvae of the cleptoparasite feed upon the food provision intended for the offspring of the host. As cleptoparasitism incurs a loss of fitness for the host organism (offspring of the host fail to develop), hosts of cleptoparasites are expected to exploit cues that alert them to potential cleptoparasite infestation. Cuticular hydrocarbons (CHCs) could serve as such cues, as insects inevitably leave traces of them behind when entering a nest. By mimicking the host's CHC profile, cleptoparasites can conceal their presence and evade detection by their host. Previous studies have provided evidence of cleptoparasites mimicking their host's CHC profile. However, the impact of this strategy on the evolution of the host's CHC profile has remained unexplored. Here, we present results from our investigation of a host–cleptoparasite system consisting of a single mason wasp species that serves syntopically as the host to three cuckoo wasp species. We found that the spiny mason wasp ( Odynerus spinipes ) is able to express two substantially different CHC profiles, each of which is seemingly mimicked by a cleptoparasitic cuckoo wasp (i.e. Chrysis mediata and Pseudospinolia neglecta ). The CHC profile of the third cuckoo wasp ( Chrysis viridula ), a species not expected to benefit from mimicking its host's CHC profile because of its particular oviposition strategy, differs from the two CHC profiles of its host. Our results corroborate the idea that the similarity of the CHC profiles between cleptoparasitic cuckoo wasps and their hosts are the result of chemical mimicry. They further suggest that cleptoparasites may represent a hitherto unappreciated force that drives the evolution of their hosts' CHCs.

scholarly journals Geographical based variations in white truffle Tuber magnatum truffle aroma is explained by quantitative differences in key volatile compounds

2020 ◽  
Author(s):  
Jun Niimi ◽  
Aurélie Deveau ◽  
Richard Splivallo
Keyword(s):  
Volatile Compounds ◽  
Fruiting Body ◽  
Geographic Area ◽  
Gas Chromatography Mass Spectrometry ◽  
List Type ◽  
Fruiting Bodies ◽  
Headspace Volatile ◽  
Microbiome Composition ◽  
Tuber Magnatum ◽  
Volatile Profiles

SummaryThe factors that vary the aroma of Tuber magnatum fruiting bodies are poorly understood. The study determined the headspace aroma composition, sensory aroma profiles, maturity, and microbiome composition from T. magnatum originating from Italy, Croatia, Hungary, and Serbia, and tested if truffle aroma is dependent on provenance and if fruiting body volatiles are explained by maturity and/or microbiome composition.Headspace volatile profiles were determined by gas chromatography-mass spectrometry-olfactometry (GC-MS-O) and aroma of fruiting body extracts were sensorially assessed. Fruiting body maturity were estimated through spore melanisation. Bacterial community was determined using 16S rRNA amplicon sequencing.Main odour active compounds were present in all truffles but varied in concentration. Aroma of truffle extracts were sensorially discriminated by sites. However, volatile profiles of individual fruiting bodies varied more within sites than across geographic area, while maturity level did not play a role. Microbiome composition varied highly and was partially explained by provenance. A few rare bacterial operational taxonomical units associated with select few non-odour active volatile compounds.Specificities of the aroma of T. magnatum truffles are more likely linked to individual properties than provenance. Some constituents of the microbiome may provide biomarkers of provenance and be linked to non-odour active volatiles.

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