Update on the defensive chemicals of the little black ant, Monomorium minimum (Hymenoptera: Formicidae)

Abstract

Alkaloids, including 2,5-dialkylpyrrolidines and 2,5-dialkylpyrrolines, have been reported to be components in the venom of little black ants, Monomorium minimum (Buckley). Two fatty amines were recently reported as minor compounds. By analyzing the discharge collected from the stinger apparatus (milking), this study revealed the presence of an additional seven compounds in the defensive secretion of this ant species. Compounds identified were 9-decenyl-1-amine, N-methylenedecan-1-amine, N-methylenedodecan-1-amine, 2-(1-non-8-enyl)-5-(1-hex-5-enyl)-1-pyrroline, N-methyl-2-(hex-5-enyl)-5-nonanyl-1-pyrrolidine, β-springene ((E,E)-7,11,15-trimethyl-3-methylene-1,6,10,14-hexadecatetraene) and neocembrene ((E,E,E)-1-isopropenyl-4,8,12-trimethylcyclotetradeca-3,7,11-triene). β-springene and neocembrene were found only in the defensive secretion of queens. Analyses of the contents of isolated poison and Dufour's glands of the queen indicated that all amines and alkaloids were from the poison gland and that β-springene and neocembrene were from the Dufour's gland. This demonstrated that the defensive secretion in M. minimum queens consists of components from both glands. This is also the first report on the natural occurrence of 9-decenyl-1-amine, N-methylenedecan-1-amine, and N-methyllenedodecan-1-amine.

Analysis of Cuticular Lipids of the Pharaoh Ant (Monomorium pharaonis) and Their Selective Adsorption on Insecticidal Zeolite Powders

“…Finally, both 2-pentyl-5-(1-hex-5-enyl)-1-pyrroline and 2-(1-hexenyl)-5-(hept-6-enyl)-1-pyrroline were also identified based on their GC-MS spectra [ 31 , 35 , 36 , 37 ]. While these exact components were not previously identified, a recent publication by Chen et al identifies several 2,5-dialkenylpyrrolines as well as a 2-alkyl-5-alkenylpyrroline in the venom of Monomorium minimum [ 38 ]. Using the same interpretation of the mass spectra ( Appendix A ) enabled the identification of these compounds.…”

“…The resulting values were averaged over all the replicates per forager sample, loaded sample or blank and compounds recovered from the blank were then subtracted from the measured forager sample and loaded sample amounts. Cuticular compounds in the samples were identified based on their mass spectra and retention indices [ 46 ], and via comparison with other studies, standards and published spectra [ 31 , 33 , 38 , 48 ]. The exact positions of alkene and alkadiene double bonds could not be determined.…”

Volatile Terpenes and Terpenoids from Workers and Queens of Monomorium chinense (Hymenoptera: Formicidae)

“…Whether neocembrene serves as queen pheromone in M. pharaonis remains questionable because it does not affect sexual brood rearing [ 40 ]. Besides two ant species mentioned above, neocembrene was detected in queens of other four species in the genus Monomorium , including M. minimum [ 41 ], M. floricola , M. destructor and M. hiten [ 42 ], indicating that neocembrene may be a genus- and queen-specific compound in genus Monomorium. Terpenes and terpenoids do not occur often in poison gland.…”

Tools in the Investigation of Volatile Semiochemicals on Insects: From Sampling to Statistical Analysis

“…Therefore, the application of NMR in topics related to VOCs that are biologically active on insects has been widely referenced for structural elucidation after the isolation of VOCs. Such cases can be exemplified (but not extensively) by the evaluation of desert locust ( Schistocerca gregaria ) secretions [127] and the compounds present in the venom of the little black ant ( Monomorium minimum ) [128], and can be used as a tool for the identification of pheromones from different insects, such as the tea moth [129], Sitophilus oryzae [130], Ectropis obliqua [131], and the azuki bean beetle ( Callosobruchus chinensis L.) [132]. In the field of plants, the investigations are much more extended regarding structural elucidation and the identification of purified compounds from essential oils with activity on insects [133,134,135] and the analysis of isolated volatile compounds from Citrus australasica [136] and Punica granatum L. [137].…”