Chemical composition and antimicrobial activity of cuticular and internal lipids of the insect Rhynchophorus palmarum

• Published in: Archives of insect biochemistry and physiology Vol. 105; no. 1; pp. e21723 - n/a
• Main Authors: Batalha, Mariana de M. C., Goulart, Henrique F., Santana, Antônio E. G., Barbosa, Leandro A. O., Nascimento, Ticiano G., Silva, Meirielly K. H., Dornelas, Camila B., Grillo, Luciano A. M.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.09.2020
• Subjects: Antiinfectives and antibacterials; Antimicrobial activity; Antimicrobial agents; antimicrobial potential; Bacteria; Chemical communication; Chemical composition; cuticle; Cuticles; E coli; Ecological studies; Esters; Fatty acids; Fungi; Gas chromatography; Insect ecology; Insecticide resistance; Insecticides; Insects; Klebsiella; Lipid composition; lipid profile; Lipids; Mass spectrometry; Mass spectroscopy; Microorganisms; Predators; Pseudomonas aeruginosa; R. palmarum; Rhynchophorus palmarum; Toxins
• ISSN: 0739-4462; 1520-6327
• DOI: 10.1002/arch.21723

Insect cuticle lipids are involved in various types of chemical communication between species, and reduce the penetration of insecticides, chemicals, and toxins, as well as provide protection against the attack of microorganisms, parasitic insects, and predators. Ecological studies related to the insect Rhynchophorus palmarum are well‐known; however, very little is known about its resistance mechanisms, which includes its lipid composition and its importance, specifically the cuticle layer. This study aimed to characterize the cuticle and internal lipid compounds of the male and female R. palmarum adult insects and to evaluate the presence of antimicrobial activity. We performed by gas chromatography coupled to mass spectrometry (GC–MS) analyzes of lipid extracts fractions and we identified 10 methyl esters of fatty acids esters of C14 to C23, with variation between the sexes of C22:0, C21:0, present only in male cuticle, and C20:2 in female. The lipid content of this insect showed relevant amount of C16:1, C18:1, and C18:2. The antimicrobial activity of the cuticular and internal fractions obtained was tested, which resulted in minimum inhibitory concentrations between 12.5 and 20 μg/ml against Gram‐positive bacteria (Staphylococcus epidermidis, Enterococcus faecalis), Gram‐negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia), and fungal species (Candida albicans e Candida tropicalis). The antimicrobial effect of the R. palmarum cuticle open perspectives for a new source to bioinsecticidal strategies, in addition to elucidating a bioactive mixture against bacteria and fungi. Characterization of the cuticle and internal lipid compounds of the male and female R. palmarum adult insects. The different composition showed activity against fungi and bacteria Highlights Lipid similarity between cuticular and internal in the main lipids C16:1, C18:1, C18:2 The female cuticle showed C22:0, in the male C21:0, and similar in the presence of C23:0 Moderate antimicrobial activity between 12.5 and 20 μg/ml