Pygidial glands of the blue ground beetle Carabus intricatus: chemical composition of the secretion and its antimicrobial activity.

Pygidial gland secretions are used as repellent defensive allomones in ground beetles. We provide the first precise data on the chemical composition and antimicrobial potency of the secretion of the blue ground beetle, as well as on the morphology of its pygidial glands. The latter structures were not previously studied chemoecologically and morphologically, and we hypothesized that their secretion may have some antimicrobial action, as is the case with certain Carabus species. Gas chromatography-mass spectrometry (GC-MS) was used to identify methacrylic and angelic acids as dominant chemicals in the secretion from individuals of three populations of the blue ground beetle in Serbia. We tested its secretion against selected strains of medically important microorganisms. The secretion exibits antimicrobial action against certain bacterial species and all tested micromycetes. The most significant antifungal effect of the secretion was against Penicillium ochrochloron, which is more sensitive to the secretion than to commercial antifungal drugs ketoconazole and bifonazole. Bifonazole achieved minimum inhibitory concentrations against Trichoderma viride at more than three times higher value than did the secretion, indicating a significant antifungal effect of the secretion against this micromycete as well. Additionally, we tested commercially available standards of two dominant chemicals in the secretion to investigate their interaction and antimicrobial role in the secretion. Finally, we describe all glandular morpho-functional units of the blue ground beetle. Our results suggest that the secretion of the blue ground beetle may serve not only defensive but also antimicrobial functions, which likely aid the survival of this beetle in the microbial-rich forest litter habitat.

"Scent of a fruit fly": Cuticular chemoprofiles after mating in differently fed Drosophila melanogaster (Diptera: Drosophilidae) strains.

In the world of complex smells in natural environment, feeding and mating represent two important olfactory-guided behaviors in Drosophila melanogaster (Diptera: Drosophilidae). Diet affects the chemoprofile composition of the individuals, which, indirectly, may significantly affect their mating success. In this study, chemoprofiles of recently mated flies belonging to four D. melanogaster strains, which were fed for many generations on different substrates (standard cornmeal-S strain; banana-B strain; carrot-C strain; tomato-T strain) were identified and quantified. In total, 67 chemical compounds were identified: 48 compounds were extracted from males maintained on banana and carrot, and 47 compounds from males maintained on cornmeal and tomato substrates, while total of 60 compounds were identified in females from all strains. The strains and the sexes significantly differed in qualitative nature of their chemoprofiles after mating. Significant differences in the relative amount of three major male pheromones (cis-vaccenyl acetate-cVA, (Z)-7-pentacosene, and (Z)-7-tricosene) and in female pheromone (Z,Z)-7,11-nonacosadiene among strains were also recorded. Furthermore, multivariate analysis of variance (MANOVA) pointed to significant differences between virgin and mated individuals of all strains and within both sexes. Differences in some of the well known sex pheromones were also identified when comparing their relative amount before and after mating. The presence of typical male pheromones in females, and vice versa may indicate their bidirectional transfer during copulation. Our results confirm significant effect of mating status on cuticular hydrocarbon (CHC) phenotypes in differently fed D. melanogaster flies.

Screening of semi-volatile compounds in plants treated with coated cerium oxide nanoparticles by comprehensive two-dimensional gas chromatography.

Literature data about semi-volatile organic compounds in plants and the effect of cerium oxide nanoparticles on them are scarce. Surface modification of nanoparticles may change nanoparticle-environment interaction, and therefore affects compounds in plants. In this research, uncoated and glucose-, levan-, and pullulan-coated cerium oxide nanoparticles were used for wheat and pea treatment during the growth. The aim was the screening of semi-volatile organic compounds from plants' shoots using comprehensive two-dimensional gas chromatography-mass spectrometry, a powerful separation technique allowing to reach unique separation resolution, and investigation of qualitative changes after the treatment with coated cerium oxide nanoparticles. The results were analyzed by the identification of individual peaks and fingerprint analysis by image processing. Wheat samples contained a higher number of semi-volatile organic compounds (108) compared to pea (77) but were less affected by the treatments with coated nanoparticles. The highest number of compounds was detected in wheat after the treatment with levan- and pullulan-coated nanoparticles, and in pea after treatment with levan-coated nanoparticles. This article reports a successful application of a semi-volatile organic compounds profile presented only as categorical variables and unique fingerprint images for the inter-cultivar recognition. This method may be useful in screening nanoparticles' effects on different plants.

GC-FID-MS Based Metabolomics to Access Plum Brandy Quality.

Plum brandy (Slivovitz (en); Sljivovica(sr)) is an alcoholic beverage that is increasingly consumed all over the world. Its quality assessment has become of great importance. In our study, the main volatiles and aroma compounds of 108 non-aged plum brandies originating from three plum cultivars, and fermented using different conditions, were investigated. The chemical profiles obtained after two-step GC-FID-MS analysis were subjected to multivariate data analysis to reveal the peculiarity in different cultivars and fermentation process. Correlation of plum brandy chemical composition with its sensory characteristics obtained by expert commission was also performed. The utilization of PCA and OPLS-DA multivariate analysis methods on GC-FID-MS, enabled discrimination of brandy samples based on differences in plum varieties, pH of plum mash, and addition of selected yeast or enzymes during fermentation. The correlation of brandy GC-FID-MS profiles with their sensory properties was achieved by OPLS multivariate analysis. Proposed workflow confirmed the potential of GC-FID-MS in combination with multivariate data analysis that can be applied to assess the plum brandy quality.

Bat guano-dwelling microbes and antimicrobial properties of the pygidial gland secretion of a troglophilic ground beetle against them.

Bat guano is an important source of microbial diversity in caves and can be a source of potential pathogens. Laemostenus (Pristonychus) punctatus is a guanophilic ground beetle species, which pygidial gland secretion exhibits action against pathogenic and other microbes. The distribution and diversity of microbes in bat guano from a karstic cave were determined in this study. Additionally, antimicrobial activity of the pygidial gland secretion of L. (P.) punctatus against guano-dwelling microbes was tested; minimal inhibitory concentration (MIC) and chemical composition of the secretion were analyzed. In total, 63 different bacterial species and 16 fungal morphotypes were isolated from guano samples by the cultivation method and confirmed using and phenotypic characterization and molecular identification. There was a difference in the composition of certain microorganisms between the sampling points (cave locations) and between the guano layers. The largest number of bacterial isolates belongs to the genera Lysinibacillus and Paenibacillus, while Pseudomonas species were highly abundant at the innermost sampling point. For the guanophilic fungi, the majority are ascomycetes, with Penicillium and Aspergillus as the most dominant genera. Meyerozyma guilliermondii was the only yeast species found in the guano samples. The most sensitive isolates were Enterococcus eurekensis (MIC 0.007 mg/mL) and Escherichia fergusonii (MIC 0.028 mg/mL). The most sensitive fungal isolates were M. guilliermondii, Penicillium expansum, and Trichoderma harzianum (MIC 0.15 mg/mL). This study opens a new possibility for better understanding of ecological relations between microorganisms and troglophilic ground beetles and for detailed investigations of morpho-anatomical aspects of pygidial glands.

Short communication: Cheese supplemented with Thymus algeriensis oil, a potential natural food preservative.

The essential oil of Thymus algeriensis was analyzed as a potential preservative in soft cheese. We developed a novel method to test the preserving properties of essential oil in soft cheese. Contamination incidence of Penicillium aurantiogriseum was absent after 30 d of storage at 4°C with 25 µL of essential oil added. The antimicrobial activity was tested against 8 bacteria and 8 fungi. Thymus algeriensis oil showed inhibitory activity against tested bacteria at 0.03 to 0.09 mg/mL, and bactericidal activity was achieved at 0.05 to 0.15 mg/mL. For antifungal activity, minimum inhibitory concentrations ranged between 0.01 and 0.04 mg/mL and minimum fungicidal concentrations between 0.01 and 0.04 mg/mL. Furthermore, the oil was also screened for antiradical activity using the 1,1-diphenyl-2-picrylhydrazyl assay. The results showed that the oil was active and achieved half-maximal inhibitory activity at 0.132 mg/mL. We used gas chromatography, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectrometry to investigate the volatile compounds from the oil. Carvacrol was identified as the main compound in the oil, represented by 80.9% of the total constituents, followed by p-cymene (7.7%).

Antifungal activity of the pygidial gland secretion of Laemostenus punctatus (Coleoptera: Carabidae) against cave-dwelling micromycetes.

The antifungal potential of the pygidial gland secretion of the troglophilic ground beetle Laemostenus punctatus from a cave in Southeastern Serbia against cave-dwelling micromycetes, isolated from the same habitat, has been investigated. Eleven collected samples were analyzed and 32 isolates of cave-dwelling fungi were documented. A total of 14 fungal species were identified as members of the genera Aspergillus, Penicillium, Alternaria, Cladosporium, Rhizopus, Trichoderma, Arthrinium, Aureobasidium, Epicoccum, Talaromyces, and Fusarium. Five isolates were selected for testing the antifungal activity of the pygidial gland secretion: Talaromyces duclauxi, Aspergillus brunneouniseriatus, Penicillium sp., Rhizopus stolonifer, and Trichoderma viride. The microdilution method has been applied to detect minimal inhibitory concentrations (MICs) and minimal fungicidal concentrations (MFCs). The most sensitive isolate was Penicillium sp., while the other isolates demonstrated a high level of resistance to the tested agent. L. punctatus has developed a special mechanism of producing specific compounds that act synergistically within the secretion mixture, which are responsible for the antifungal action against pathogens from the cave. The results open opportunities for further research in the field of ground beetle defense against pathogens, which could have an important application in human medicine, in addition to the environmental impact, primarily.

Chemical Ecology of Cave-Dwelling Millipedes: Defensive Secretions of the Typhloiulini (Diplopoda, Julida, Julidae).

Cave animals live under highly constant ecological conditions and in permanent darkness, and many evolutionary adaptations of cave-dwellers have been triggered by their specific environment. A similar "cave effect" leading to pronounced chemical interactions under such conditions may be assumed, but the chemoecology of troglobionts is mostly unknown. We investigated the defensive chemistry of a largely cave-dwelling julid group, the controversial tribe "Typhloiulini", and we included some cave-dwelling and some endogean representatives. While chemical defense in juliform diplopods is known to be highly uniform, and mainly based on methyl- and methoxy-substituted benzoquinones, the defensive secretions of typhloiulines contained ethyl-benzoquinones and related compounds. Interestingly, ethyl-benzoquinones were found in some, but not all cave-dwelling typhloiulines, and some non-cave dwellers also contained these compounds. On the other hand, ethyl-benzoquinones were not detected in troglobiont nor in endogean typhloiuline outgroups. In order to explain the taxonomic pattern of ethyl-benzoquinone occurrence, and to unravel whether a cave-effect triggered ethyl-benzoquinone evolution, we classed the "Typhloiulini" investigated here within a phylogenetic framework of julid taxa, and traced the evolutionary history of ethyl-benzoquinones in typhloiulines in relation to cave-dwelling. The results indicated a cave-independent evolution of ethyl-substituted benzoquinones, indicating the absence of a "cave effect" on the secretions of troglobiont Typhloiulini. Ethyl-benzoquinones probably evolved early in an epi- or endogean ancestor of a clade including several, but not all Typhloiulus (basically comprising a taxonomic entity known as "Typhloiulus sensu stricto") and Serboiulus. Ethyl-benzoquinones are proposed as novel and valuable chemical characters for julid systematics.

The pygidial gland secretion of the forest caterpillar hunter, Calosoma (Calosoma) sycophanta: the antimicrobial properties against human pathogens.

Recently, various insect secretions have been tested as possible antimicrobial agents. In beetles, these secretions are essentially products of various exocrine glands, of which particular emphasis is on pygidial glands that are common for the suborder Adephaga. The antimicrobial potential of the pygidial gland secretion isolated from the adults of Calosoma sycophanta against human pathogens has been tested and compared with the potential of other carabid species, particularly within the tribe Carabini. The antimicrobial assay includes a microdilution method which was applied in order to determine the minimal inhibitory, minimal fungicidal and minimal bactericidal concentrations. It has been tested the effect of the secretion against eight strains of fungal and eight strains of bacterial species. The secretion sample of the tested carabid species has shown statistically significant antifungal effect against all strains of treated micromycetes, the highest in comparison with previously tested carabids (Carabus spp., Laemostenus punctatus and Abax parallelepipedus). Aspergillus versicolor proved to be the most sensitive micromycete, while the remaining seven fungal strains have shown the same level of sensibility. In comparison with commercial mycotics ketoconazole and bifonazole, applied as positive controls, the tested secretion showed much higher antifungal activity for all fungal strains. Antibacterial effect has been manifested only against one bacterial strain (Escherichia coli), contrary to other previously studied carabid species. These observations might have a significant impact on the ecological domain and possible purpose in biomedical studies and applications in the future. Additionally, morpho-histology of the pygidial glands of C. sycophanta is investigated and discussed.

Antimicrobial activity of the pygidial gland secretion of three ground beetle species (Insecta: Coleoptera: Carabidae).

The antimicrobial properties of the pygidial gland secretions released by the adults of the three ground beetle species, Carabus ullrichii, C. coriaceus, and Abax parallelepipedus, have been tested. Microdilution method was applied for detection of minimal inhibitory concentrations (MICs), minimal bactericidal concentrations (MBCs), and minimal fungicidal concentrations (MFCs). Additionally, morpho-histology of the pygidial glands is investigated. We have tested 16 laboratory and clinical strains of human pathogens--eight bacterial both gram-positive and gram-negative species and eight fungal species. The pygidial secretion samples of C. ullrichii have showed the strongest antimicrobial effect against all strains of treated bacteria and fungi. Staphylococcus aureus, Lysteria monocytogenes, and Salmonella typhimurium proved to be the most sensitive bacterial strains. Penicillium funiculosum proved to be the most sensitive micromycete, while P. ochrochloron and P. verrucosum var. cyclopium the most resistant micromycetes. The pygidial secretion of C. coriaceus has showed antibacterial potential solely against Pseudomonas aeruginosa and antifungal activity against Aspergillus fumigatus, A. versicolor, A. ochraceus, and P. ochrochloron. Antibacterial properties of pygidial gland secretion of A. parallelepipedus were achieved against P. aeruginosa, while antifungal activity was detected against five of the eight tested micromycetes (A. fumigatus, A. versicolor, A. ochraceus, Trichoderma viride, and P. verrucosum var. cyclopium). Commercial antibiotics Streptomycin and Ampicillin and mycotics Ketoconazole and Bifonazole, applied as the positive controls, showed higher antibacterial/antifungal properties for all bacterial and fungal strains. The results of this observation might have a significant impact on the environmental aspects and possible medical purpose in the future.

"Quinone Millipedes" Reconsidered: Evidence for a Mosaic-Like Taxonomic Distribution of Phenol-Based Secretions across the Julidae.

The defensive chemistry of juliformian millipedes is characterized mainly by benzoquinones ("quinone millipedes"), whereas the secretions of the putative close outgroup Callipodida are considered to be exclusively phenolic. We conducted a chemical screening of julid secretions for phenolic content. Most species from tribes Cylindroiulini (15 species examined), Brachyiulini (5 species examined), Leptoiulini (15 species examined), Uncigerini (2 species examined), Pachyiulini (3 species examined), and Ommatoiulini (2 species examined) had non-phenolic, in most cases exclusively benzoquinonic secretions. In contrast, tribes Cylindroiulini, Brachyiulini, and Leptoiulini also contained representatives with predominantly phenol-based exudates. In detail, p-cresol was a major compound in the secretions of the cylindroiulines Styrioiulus pelidnus and S. styricus (p-cresol content 93 %) and an undetermined Cylindroiulus species (p-cresol content 51 %), in the brachyiulines Brachyiulus lusitanus (p-cresol content 21 %) and Megaphyllum fagorum (p-cresol content 92 %), as well as in an undescribed Typhloiulus species (p-cresol content 32 %, Leptoiulini). In all species, p-cresol was accompanied by small amounts of phenol. The secretion of M. fagorum was exclusively phenolic, whereas phenols were accompanied by benzoquinones in all other species. This is the first incidence of clearly phenol-dominated secretions in the Julidae. We hypothesize a shared biosynthetic route to phenols and benzoquinones, with benzoquinones being produced from phenolic precursors. The patchy taxonomic distribution of phenols documented herein supports multiple independent regression events in a common pathway of benzoquinone synthesis rather than multiple independent incidences of phenol biosynthesis.

'Does my Diet Affect my Perfume?' Identification and Quantification of Cuticular Compounds in Five Drosophila melanogaster Strains Maintained over 300 Generations on Different Diets.

Cuticular hydrocarbons (CHCs) in Drosophila melanogaster represent the basis of chemical communication being involved in many important biological functions. The aim of this study was to characterize chemical composition and variation of cuticular profiles in five D. melanogaster strains. These strains were reared for approximately 300 generations on five diets: standard cornmeal medium and substrates prepared with apple, banana, tomato, and carrot. Differences in quantity and/or quality in CHCs were assumed as a result of activation of different metabolic pathways involved in food digestion and adaptations to the particular diet type. In total, independently of sex and strain, 66 chemical compounds were identified. In females of all strains, 60 compounds were identified, while, in males, 47 compounds were extracted. Certain new chemical compounds for D. melanogaster were found. MANOVA confirmed that CHC amounts significantly depend on sex and substrates, as well as on their interactions. Discriminant analysis revealed that flies belonging to 'apple' and 'carrot' strains exhibited the most noticeable differences in CHC repertoires. A non-hydrocarbon pheromone, cis-vaccenyl acetate (cVA) also contributed to the variation in the pheromone bouquet among the strains. Variability detected in CHCs and cVA may be used in the explanation of differences in mating behaviour previously determined in analyzed fly strains.

Molecular Diversity of Compounds from Pygidial Gland Secretions of Cave-Dwelling Ground Beetles: The First Evidence.

Three adult cave-dwelling ground beetle species were induced to discharge secretions of their pygidial glands into vials. Dichloromethane extraction was used to obtain the secretions. In total, 42 compounds were identified by GC/MS analysis. Pheggomisetes ninae contained 32 glandular compounds, Laemostenus (Pristonychus) punctatus 13, whereas Duvalius (Paraduvalius) milutini had nine compounds. Caproic, oleic, palmitic, and stearic acids were present in the samples of all analyzed species. Undecane was predominant in the extract of L. punctatus. Palmitic acid was the major component in the secretion of D. milutini. Finally, the most abundant compounds in P. ninae secretion were heptacosene and nonacosadienes. Herein, we present the first data on the identification of pygidial gland secretion components in both troglophilous and troglobite cave-dwelling ground beetles. Some compounds are reported for the first time in the secretions of ground beetles and other higher or lower taxa. The adaptation to underground life has not led to a reduction or changes in the chemical defense mechanism in the analyzed troglophilous and troglobitic Platyninae and Trechinae taxa.

Chemical defense in millipedes (Myriapoda, Diplopoda): do representatives of the family Blaniulidae belong to the 'quinone' clade?

The defensive secretions of two blaniulid millipedes, Nopoiulus kochii and Cibiniulus phlepsii, were characterized by GC-FID and GC/MS analyses, which showed the presence of a complex mixture of benzoquinones, hydroquinones, and oleates. Altogether, 13 compounds were identified. The major compound in the secretions of both analyzed species was 2-methyl-1,4-benzoquinone (toluquinone). The second major constituent in the N. kochii secretion was 2-methyl-3,4-(methylenedioxy)phenol, while in that of C. phlepsii, it was 2-methoxy-3-methyl-1,4-benzoquinone. The defensive secretion of N. kochii also showed a high content of hydroquinones (13.5%) in comparison to that of C. phlepsii (0.8%). Hexyl oleate and octyl oleate were detected for the first time in defensive millipede fluids. The chemical composition of the defensive secretions supports the chemotaxonomic position of the family Blaniulidae in the 'quinone' millipede clade.

Critical Review of Selected Analytical Platforms for GC-MS Metabolomics Profiling-Case Study: HS-SPME/GC-MS Analysis of Blackberry's Aroma.

Data processing and data extraction are the first, and most often crucial, steps in metabolomics and multivariate data analysis in general. There are several software solutions for these purposes in GC-MS metabolomics. It becomes unclear which platform offers what kind of data and how that information influences the analysis's conclusions. In this study, selected analytical platforms for GC-MS metabolomics profiling, SpectConnect and XCMS as well as MestReNova software, were used to process the results of the HS-SPME/GC-MS aroma analyses of several blackberry varieties. In addition, a detailed analysis of the identification of the individual components of the blackberry aroma club varieties was performed. In total, 72 components were detected in the XCMS platform, 119 in SpectConnect, and 87 and 167 in MestReNova, with automatic integral and manual correction, respectively, as well as 219 aroma components after manual analysis of GC-MS chromatograms. The obtained datasets were fed, for multivariate data analysis, to SIMCA software, and underwent the creation of PCA, OPLS, and OPLS-DA models. The results of the validation tests and VIP-pred. scores were analyzed in detail.

Chemical defence of a centipede (Clinopodes flavidus).

Chemical substances are of utmost importance for the biotic interactions between animals and their predators/parasites; many of these semiochemicals are emitted for defence purposes. One of the most deterrent and toxic biogenic substances we know of is hydrogen cyanide, which can be stored by certain insects, millipedes, centipedes and arachnids in the form of stable and less volatile molecules. The aim of this study was to analyse the biology and chemistry of such a defence mechanism in a geophilomorph centipede (Chilopoda). The cyanogenic secretion of Clinopodes flavidus is discharged from the ventral glands, whose glandular units are located in the space between the cuticle and the trunk muscles and do not extend deep into the segment. In addition to hydrogen cyanide, the ventral secretion contains 2-methylpentanoic acid, benzaldehyde, benzoyl cyanide, 2-methyl branched C-9 carboxylic acid (tentatively identified as 2-methyloctanoic acid), methyl 2-phenylacetate, benzoic acid and mandelonitrile as well as four major proteins with a molecular weight of 150, 66.2, 59 and 55 kDa. The correlation between the presence of ventral glands and guarding with the female's ventral side facing away from the eggs and young indicates a functional link between these two traits. We hope that the specificity of the chemical composition of the ventral secretion could serve as a criterion for chemotaxonomy and that the analysis of more species will help to clarify the phylogenetic relationships within the Geophilomorpha.

The morphology of the pygidial glands and the chemical composition of their secretions of four sphodrine ground beetle species (Carabidae: Platyninae).

Ground beetles possess a pair of pygidial glands that produce and release secretions that play an important role in defense against predators. The morphology of these glands and the chemical composition of their products were studied in four species of the tribe Sphodrini: Calathus (Calathus) fuscipes (Goeze, 1777), C. (Neocalathus) cinctus Motschulsky, 1850, C. (N.) melanocephalus (Linnaeus, 1758) and Laemostenus (Antisphodrus) elongatus (Dejean, 1828). The morphological analyzes of the glands of the four taxa mentioned were carried out for the first time using bright-field and nonlinear microscopy. All morphological structures were precisely measured and photographed. The pygidial gland secretions of C. (C.) fuscipes and L. (A.) elongatus were analyzed for the first time using gas chromatography-mass spectrometry. A total of 30 compounds were detected from the extracts of pygidial gland secretions of the four Sphodrini species studied. The simplest chemical mixture was found in L. (A.) elongatus, while the most complex secretion was that of C. (C.) fuscipes. 1-Undecanol, which we were able to detect in all taxa examined here, and dodecyl butyrate, which was detected in the three Calathus species, have never before been detected in the secretions of ground beetles.

Secretory Tissues and Volatile Components of Disc Florets in Several Wild Helianthus L. Species.

Although flower pollinator interactions are known to be mediated by floral traits, not enough attention has been paid to the research of secretory tissues and volatile components of sunflower disc florets as potentially important parameters in breeding programs. (1) To our knowledge, this is the first integrated study aimed at better understanding the attractiveness of sunflower capitula to insects. In the study, we have made a very detailed comparative analysis of secretory tissues and the characterization of the volatile components (VOCs) of disc florets in 10 wild perennial Helianthus species. (2) For anatomical analyses, cross-sections were obtained from the nectary zone of disc florets using a cryotechnique procedure. Micromorphological observation and morphological and anatomical analysis of disc florets were performed using light and scanning electron microscopy. For VOCs, we applied headspace, GC-FID, and GC/MS analyses. (3) The obtained results indicate that there is a difference between the analyzed traits among studied species. H. eggertii, H. hirsutus, H. mollis, H. resinosus, and H. tuberosus had high disc diameter values, a high cross-section area and disc floret corolla length, as well as the largest cross-section area and thickness of the disc florets nectary. In the analyzed VOCs, 30 different compounds were detected. The highest yield and quantity of α-Pinene was observed in H. mollis. (4) Inflorescence features, such as receptacle diameter, corolla and secretory tissue properties, and floret VOCs production and characterization, provided valuable information that can be used as guidelines in sunflower breeding programs to maximize pollinator attractiveness and increase seed yield.

Clinopodium L. Taxa from the Balkans-Are There Unique Leaf Micromorphological and Phytochemical Patterns?

The concept of the genus Clinopodium L. has changed considerably since its first description. Most of the currently accepted species of the genus have traditionally been treated as separate genera in the group Satureja sensu lato: Clinopodium L., Calamintha sensu Miller or Moench, and Acinos sensu Miller or Moench. This study aimed to gain a better insight into the species diversity of Clinopodium L. from the Balkans by analyzing the taxa that have traditionally been placed in separate genera. The alkane profile and the micromorphological characteristics of the leaves are analyzed. The leaves are visualized using scanning electron microscopy, and alkanes are isolated using n-hexane as a solvent and analyzed using gas chromatography/mass spectrometry. The alkane profile showed the differentiation of the Acinos-group from the other taxa based on the dominant n-C31, while most of the other taxa contained n-C33 as the dominant alkane. The micromorphological features also showed clear differences between the previously recognized genera, especially in the capitate trichomes. The results showed that micromorphological patterns are highly variable in certain groups of the genus Clinopodium.

Morphology of the pygidial glands and chemical composition of their secretions in two species of tiger beetles (Carabidae: Cicindelinae).

Pygidial glands are a common feature of all adephagans and their products play an important role in defense against predators. The morphology of the pygidial glands and the chemistry of their secretion were studied for the first time in two species of tiger beetles - Cicindela (Cicindela) sylvicola Dejean, 1822 and Cylindera (Cylindera) germanica (Linnaeus, 1758). The glands were examined by both bright-field microscopy and nonlinear microscopy. All morphological structures of the glands were measured and described in detail. The structures mentioned were compared with those of related taxa. The secretion extracts from the pygidial glands of the investigated taxa contained a total of 24 compounds, which were detected by gas chromatography-mass spectrometry (GC-MS). The secretion mixture of C. (C.) germanica was more complex (21 chemicals) than that of C. (C.) sylvicola (11 ones). Benzaldehyde was present in both secretion samples. Hydrocarbons were the most abundant group of secretory compounds. The purpose of the compounds, their distribution within the subfamily Cicindelinae and their effects on the ecology of the group were discussed.