Laboratory evaluation of natural and synthetic aromatic compounds as potential attractants for male mediterranean fruit fly, ceratitis capitata

Ceratitis capitata, the Mediterranean fruit fly, is one of the most serious agricultural pests worldwide responsible for significant reduction in fruit and vegetable yields. Eradication is expensive and often not feasible. Current control methods include the application of conventional insecticides, leading to pesticide resistance and unwanted environmental effects. The aim of this study was to identify potential new attractants for incorporation into more environmentally sound management programs for C. capitata. In initial binary choice bioassays against control, a series of naturally occurring plant and fungal aromatic compounds and their related analogs were screened, identifying phenyllactic acid (7), estragole (24), o-eugenol (21), and 2-allylphenol (23) as promising attractants for male C. capitata. Subsequent binary choice tests evaluated five semisynthetic derivatives prepared from 2-allylphenol, but none of these were as attractive as 2-allylphenol. In binary choice bioassays with the four most attractive compounds, males were more attracted to o-eugenol (21) than to estragole (24), 2-allylphenol (23), or phenyllactic acid (7). In addition, electroantennography (EAG) was used to quantify antennal olfactory responses to the individual compounds (1–29), and the strongest EAG responses were elicited by 1-allyl-4-(trifluoromethyl)benzene (11), estragole (24), 4-allyltoluene (14), trans-anethole (9), o-eugenol (21), and 2-allylphenol (23). The compounds evaluated in the current investigation provide insight into chemical structure–function relationships and help direct future efforts in the development of improved attractants for the detection and control of invasive C. capitata

Liquid and vapour-phase antifungal activities of selected essential oils against candida albicans: microscopic observations and chemical characterization of cymbopogon citratus

<p>Abstract</p> <p>Background</p> <p>Use of essential oils for controlling <it>Candida albicans </it>growth has gained significance due to the resistance acquired by pathogens towards a number of widely-used drugs. The aim of this study was to test the antifungal activity of selected essential oils against <it>Candida albicans </it>in liquid and vapour phase and to determine the chemical composition and mechanism of action of most potent essential oil.</p> <p>Methods</p> <p>Minimum Inhibitory concentration (MIC) of different essential oils in liquid phase, assayed through agar plate dilution, broth dilution & 96-well micro plate dilution method and vapour phase activity evaluated through disc volatilization method. Reduction of <it>C. albicans </it>cells with vapour exposure was estimated by kill time assay. Morphological alteration in treated/untreated <it>C. albicans </it>cells was observed by the Scanning electron microscopy (SEM)/Atomic force microscopy (AFM) and chemical analysis of the strongest antifungal agent/essential oil has been done by GC, GC-MS.</p> <p>Results</p> <p>Lemon grass (<it>Cymbopogon citratus</it>) essential oil exhibited the strongest antifungal effect followed by mentha (<it>Mentha piperita</it>) and eucalyptus (<it>Eucalyptus globulus</it>) essential oil. The MIC of lemon grass essential oil in liquid phase (288 mg/l) was significantly higher than that in the vapour phase (32.7 mg/l) and a 4 h exposure was sufficient to cause 100% loss in viability of <it>C. albicans </it>cells. SEM/AFM of <it>C. albicans </it>cells treated with lemon grass essential oil at MIC level in liquid and vapour phase showed prominent shrinkage and partial degradation, respectively, confirming higher efficacy of vapour phase. GC-MS analysis revealed that lemon grass essential oil was dominated by oxygenated monoterpenes (78.2%); α-citral or geranial (36.2%) and β-citral or neral (26.5%), monoterpene hydrocarbons (7.9%) and sesquiterpene hydrocarbons (3.8%).</p> <p>Conclusion</p> <p>Lemon grass essential oil is highly effective in vapour phase against <it>C. albicans</it>, leading to deleterious morphological changes in cellular structures and cell surface alterations.</p

Anti-inflammatory and healing action of oral gel containing borneol monoterpene in chemotherapy-induced mucositis in rats ( Rattus norvegicus )

ABSTRACT The aim of this study was to investigate the effect of gels containing the monoterpene borneol in induced oral mucositis using an animal model. Gels were prepared with borneol at 1.2% and 2.4% (w/w). Oral mucositis was induced by administration of three doses of 5-fluorouracil (30 mg/kg, i.p.) and injury with acetic acid (50%, v/v) soaked in filter paper applied to right cheek mucosa for 60s. Four subgroups comprising 12 animals each were formed. Six animals from each group were sacrificed at days seven and fourteen after oral mucositis induction. Mucous samples were processed and stained with hematoxylin-eosin and Masson’s Trichrome. The semiquantitative evaluation involved observation of inflammatory parameters. ImageJ® software was used in the quantitative evaluation. For statistical analyses, Two-way ANOVA, followed by Tukey’s post-test (p <0.05), were employed. Borneol 2.4% gel proved effective in the treatment of oral mucositis with statistically significant differences between groups for angiogenesis control, inflammatory cell count reduction and percentage neoformed collagen increase. The confirmation of anti-inflammatory and healing action of borneol in oral mucositis in rats renders it a good marker for predicting this activity for plant extracts rich in this substance

Harnessing chemical ecology for improved pest management- advances and future opportunities

One aspect of chemical ecology is the study of interactions between organisms across trophic levels that are mediated by naturally occurring chemicals. These chemical cues are produced by organisms, including plants, insects, and microorganisms, enabling them to communicate intra- and inter-specifically. These cues can be exploited for the management of pests that affect crops through several mechanisms, including, but not limited to, inducing plant defences against pests, direct suppression of pests, and signalling to beneficial predators/parasitoids for pest control. Identifying the chemical cues (semiochemicals) involved in these biological activities, and advancing our understanding of their roles could enable the development of novel, sustainable tools to increase crop productivity. This special issue presents 21 articles published in Pest Manag. Sci. from 2023 to 2025 that report on plant-insect-microbe interactions and microbe-insect interactions. This editorial has a brief overview of manuscripts from the special issue, highlighting substantial advancements in chemical ecology research and priorities for future research. We hope this special issue inspires new ideas for the future of chemical ecology research, highlights opportunities for joint and collaborative approaches, and showcases cutting-edge research that can advance the field forward in tackling global pest management challenges in agricultural and horticultural crop

Cycloartane triterpene glycosides from the roots of Astragalus gilvus Boiss

WOS: 00023207420000

Chemical composition and mosquitocidal activity of n-hexane and methanolic extracts from Euphorbia anacampseros var. tmolea: An endemic species of Turkey against Aedes aegypti

Volatile composition of the n-hexane and methanol extracts from E. anacampseros var. tmolea was analyzed by head space-solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Chemical characterization of the methanolic extract was determined by LC-ESI-MS/MS. Both extracts were bioassayed against 1st instar larvae and adult female Ae. aegypti. The main components identified from the E. anacampseros var. tmolea n-hexane fraction were 1,8-cineole (27.5 %), p-cymene (25 %), ?-terpinene (12.8 %), limonene (9.9 %). Methyl hexanoate (18.8 %), methyl nonanoate (13.3 %), dimethyl succinate (6.5 %), methyl octanoate (6 %) and methyl phenylacetate (5.3 %) were identified from the methanolic fraction. The n-hexane extract showed 100 % mortality at 0.1 µg/ µL against 1st instar larvae of Ae. aegypti and the methanolic extract exhibited 83.3 % mortality at 5 µg/mosquito against adult female Ae. aegypti. The bioassay-guided study demonstrates that n-hexane and methanol extracts of E. anacampseros var. tmolea contain compounds with natural mosquito larvicidal and adulticidal activity.U.S. Department of DefenseThis study was partly funded by the Deployed War-Fighter Protection Research Program via grants from the U.S. Department of Defense through the Armed Forces Pest Management Board. The authors thank Miss Jessica Louton (USDA-ARS, CMAVE, Gainesville, FL) for the mosquito bioassays. -