Exploring market-available pheromone lures and traps for monitoring Anthonomus testaceosquamosus (Coleoptera: Curculionidae).

The hibiscus bud weevil (HBW), Anthonomus testaceosquamosus Linell (Coleoptera: Curculionidae), is a significant threat to tropical hibiscus (Hibiscus rosa-sinensis) in Florida, USA, since its invasion in 2017. As a regulated pest in the state, early detection is crucial. Based on the success of pheromone-based monitoring programs for other weevil pests, such as the boll weevil, cranberry weevil, and pepper weevil, this study explores the potential use of these pheromone lures for early detection of HBW. To account for differences in efficacy based on trap color, height, and design, different pheromone lure sizes (4 mm, 10 mm, full-size), trap types (Yellow sticky trap, Japanese beetle trap, Boll weevil trap), and heights (0 m, 1.1 m) were also tested in this study. In laboratory assays, males and females exhibited higher attraction to full-size cranberry weevil lure discs than other lure size-type combinations. In semi-field trials, yellow sticky traps baited with cranberry weevil lures captured more weevils than Japanese beetle or boll weevil traps baited with cranberry weevil lures, while trap height did not influence HBW capture. In semi-field, 4-choice bioassays, yellow sticky traps baited with cranberry weevil lures captured more HBW compared to yellow sticky traps baited with pepper weevil, boll weevil, or unbaited traps. Further research is required to thoroughly evaluate the cranberry weevil lure's efficacy in capturing HBW. Our study suggests the potential for utilizing yellow sticky traps baited with lures for early HBW detection and highlights the importance of selecting the appropriate lure, trap type, and height for optimal efficacy.

Insecticidal effect of new synthesized chalcone derivatives on Caribbean fruit fly, Anastrepha suspensa.

In this present study, new chalcone derivatives were synthesized from 4-aminoacetophenone, which were confirmed by spectroscopic methods. The toxic risks of chalcones to humans and the environment were investigated by a web-based platform called ADMETlab. With this program, the possible toxic effects of the compounds on liver, respiratory system, and eyes were evaluated. For the topical insecticidal activity, adult female Caribbean fruit fly, Anastrepha suspensa, was targeted. Results of the toxicity tests showed that chalcone derivatives are effective against female A. suspensa. Among the synthesized chalcones, 1-(4-cinnamoylphenyl)-3-(p-tolyl)urea (2) exhibited the greatest insecticidal activity, resulting in 73 % mortality at 100 µg/fly after 24 h, whereas other derivatives showed less than 30 % mortality. Our results demonstrate that insecticidal activity may be modulated by the presence of a certain phenyl ring in the structure of derivative 2 and, therefore, has potential for design of efficient chemicals for tephritid fruit fly management.

Volatile Characterization of Lychee Plant Tissues (Litchi chinensis) and the Effect of Key Compounds on the Behavior of the Lychee Erinose Mite (Aceria litchii).

Herbivore-Induced Plant Volatiles (HIPVs) are volatile signals emitted by plants to deter herbivores and attract their natural enemies. To date, it is unknown how lychee plants, Litchi chinensis, respond to the induction of leaf galls (erinea) caused by the lychee erinose mite (LEM), Aceria litchii. Aiming to reveal the role of HIPVs in this plant-mite interaction, we investigated changes in the volatile profile of lychee plants infested by LEM and their role on LEM preferences. The volatile profile of uninfested (flower buds, fruit, leaves and new leaf shoots) and infested plant tissue were characterized under different levels of LEM infestation. Volatiles were collected using head-space-solid phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analyses. Fifty-eight volatiles, including terpenoids, alcohols, aldehydes, alkanes, esters, and ketones classes were identified. Using dual-choice bioassays, we investigated the preference of LEM to uninfested plant tissues and to the six most abundant plant volatiles identified. Uninfested new leaf shoots were the most attractive plant tissues to LEM and LEM attraction or repellence to volatiles were mostly influenced by compound concentration. We discuss possible applications of our findings in agricultural settings.

Deciphering Plant-Insect-Microorganism Signals for Sustainable Crop Production.

Agricultural crop productivity relies on the application of chemical pesticides to reduce pest and pathogen damage. However, chemical pesticides also pose a range of ecological, environmental and economic penalties. This includes the development of pesticide resistance by insect pests and pathogens, rendering pesticides less effective. Alternative sustainable crop protection tools should therefore be considered. Semiochemicals are signalling molecules produced by organisms, including plants, microbes, and animals, which cause behavioural or developmental changes in receiving organisms. Manipulating semiochemicals could provide a more sustainable approach to the management of insect pests and pathogens across crops. Here, we review the role of semiochemicals in the interaction between plants, insects and microbes, including examples of how they have been applied to agricultural systems. We highlight future research priorities to be considered for semiochemicals to be credible alternatives to the application of chemical pesticides.

Piperitone (p-Menth-1-En-3-One): A New Repellent for Tea Shot Hole Borer (Coleoptera: Curculionidae) in Florida Avocado Groves.

The tea shot hole borer, Euwallacea perbrevis, has been recently established in Florida, USA, where it vectors fungal pathogens that cause Fusarium dieback in avocado. Pest monitoring uses a two-component lure containing quercivorol and α-copaene. Incorporation of a repellent into IPM programs may reduce the incidence of dieback in avocado groves, particularly if combined with lures in a push-pull system. This study evaluated piperitone and α-farnesene as potential repellents for E. perbrevis, comparing their efficacy to that of verbenone. Replicate 12-week field tests were conducted in commercial avocado groves. Each test compared beetle captures in traps baited with two-component lures versus captures in traps containing lures plus repellent. To complement field trials, Super-Q collections followed by GC analyses were performed to quantify emissions from repellent dispensers field-aged for 12 weeks. Electroantennography (EAG) was also used to measure beetle olfactory response to each repellent. Results indicated that α-farnesene was ineffective; however, piperitone and verbenone were comparable in repellency, achieving 50-70% reduction in captures, with longevity of 10-12 weeks. EAG responses to piperitone and verbenone were equivalent, and significantly greater than response to α-farnesene. Since piperitone is less expensive than verbenone, this study identifies a potential new E. perbrevis repellent.

HPTLC Analysis and Chemical Composition of Selected Melaleuca Essential Oils.

Tea tree oil (TTO) is a volatile essential oil obtained by distillation, mainly from the Australian native plant Melaleuca alternifolia (Maiden & Betche) Cheel (Myrtaceae). In this study, a comparative analysis of the chemical constituents of seven tea tree oils (M. alternifolia) and four other Melaleuca spp. oils (M. cajuputi, (MCa), two chemotypes of M. quinquenervia, (MNe and MNi), and M. ericifolia (MRo)) was carried out using gas chromatography-mass spectrometry (GC-MS) and high-performance thin-layer chromatography (HPTLC). Among the seven TTOs, terpinen-4-ol (37.66-44.28%), γ-terpinene (16.42-20.75%), α-terpinene (3.47-12.62%), α-terpineol (3.11-4.66%), and terpinolene (2.75-4.19%) were the most abundant compounds. On the other hand, the most abundant compounds of the other Melaleuca oils varied, such as 1,8-cineole (64.63%) in MCa oil, (E)-nerolidol (48.40%) and linalool (33.30%) in MNe oil, 1,8-cineole (52.20%) in MNi oil, and linalool (38.19%) and 1,8-cineole (27.57%) in MRo oil. HPTLC fingerprinting of Melaleuca oils enabled the discrimination of TTO oils from other Melaleuca spp. oils. Variation was observed in the profile of the Rf values among EOs. The present study shows that HPTLC is one of the best ways to identify and evaluate the quality control in authenticating TTOs, other Melaleuca EOs, or EOs from other species within the Myrtaceae.

Synthesis of Phthalimide Derivatives and Their Insecticidal Activity against Caribbean Fruit Fly, Anastrepha suspensa (Loew).

In this study, thirteen phthalimide derivatives were designed and synthesized. All synthesized compounds were evaluated to determine their potential for inhibitory activities against females of the Caribbean fruit fly, Anastrepha suspensa (Loew) (Diptera: Tephritidae). These efforts led to the discovery of three compounds 4a, 4c, and 4d with potent insecticidal activity (LD50 range from 0.70 to 1.91 µg/fly). Among these compounds, 4a exhibited the highest inhibitory potency with 0.70 µg/fly. In addition, in silico models indicated that compound 4a is less toxic than phthalimide and other precursors. Therefore, our results suggest that 4a has strong potential as a candidate component for developing a novel environmentally friendly insecticide for control of pest fruit flies.

Development of a Kairomone-Based Attractant as a Monitoring Tool for the Cocoa Pod Borer, Conopomorpha cramerella (Snellen) (Lepidoptera: Gracillariidae).

The cocoa pod borer (CPB), Conopomorpha cramerella, is a major economic pest of cocoa, Theobroma cacao, in Southeast Asia. CPB monitoring programs currently use a costly synthetic pheromone lure attractive to males. Field trapping experiments demonstrating an effective plant-based alternative are presented in this study. Five lychee-based products were compared for their attractiveness to CPB males. The organic lychee flavor extract (OLFE), the most attractive product, captured significantly more CPB as a 1 mL vial formulation than unbaited traps, while being competitive with the commercial pheromone lures. Additional experiments show that a 20 mL membrane OLFE lure was most effective, attracting significantly more CPB than the pheromone. When the kairomone and pheromone lures were combined, no additive or synergistic effects were observed. Concentrating the OLFE product (OLFEc) using a rotary evaporator increased the lure attractiveness to field longevity for up to 28 weeks; in contrast, pheromone lures were effective for approximately 4 weeks. The 20 mL concentrated OLFE membrane lures should provide a cheaper and more efficient monitoring tool for CPB than the current commercial pheromone lures.

Studies on the Volatiles Composition of Stored Sheep Wool, and Attractancy toward Aedes aegypti Mosquitoes.

To discover new natural materials for insect management, commercially available stored sheep wool was investigated for attractancy to female adult Aedes aegypti mosquitoes. The volatiles from sheep wool were collected by various techniques of headspace (HS) extractions and hydrodistillation. These extracts were analyzed using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detector (GC-FID) coupled with GC-MS. Fifty-two volatile compounds were detected, many of them known for their mosquito attractant activity. Seven compounds were not previously reported in sheep products. The volatile composition of the extracts varied significantly across collections, depending on the extraction techniques or types of fibers applied. Two types of bioassay were conducted to study attractancy of the sheep wool volatiles to mosquitoes: laboratory bioassays using glass tubes, and semi-field bioassays using large, screened outdoor cages. In bioassays with glass tubes, the sheep wool hydrodistillate and its main component, thialdine, did not show any significant attractant activity against female adult Ae. aegypti mosquitoes. Semi-field bioassays in two large screened outdoor cages, each equipped with a U.S. Centers for Disease Control (CDC) trap and the various bait setups with Vortex apparatus, revealed that vibrating wool improved mosquito catches compared to the setups without wool or with wool but not vibrating. Sheep wool, when vibrated, may release intensively volatile compounds, which could serve as olfactory cues, and play significant role in making the bait attractive to mosquitoes. Sheep wool is a readily available, affordable, and environment-friendly material. It should have the potential to be used as a mosquito management and surveillance component in dynamic bait setups.

Volatile Emissions and Relative Attraction of the Fungal Symbionts of Tea Shot Hole Borer (Coleoptera: Curculionidae).

Euwallacea perbrevis is an ambrosia beetle that vectors fungal pathogens causing Fusarium dieback in Florida avocado trees. Current monitoring lures contain quercivorol, a fungus-produced volatile, but the exact attractant is unknown since lures contain a mixture of p-menth-2-en-1-ol isomers and both α- and ß-phellandrene. This study used pure cultures of six symbiotic fungi isolated from E. perbrevis to document volatile emissions and determine the relative attraction of symbionts in binary choice assays. In a comparative test, headspace solid-phase microextraction followed by gas chromatography-mass spectroscopy was used to identify and quantify emissions from 3-week-old cultures. In a temporal study, Super-Q collection followed by gas chromatography-flame ionization detection was used to measure cis- and trans-p-menth-2-en-1-ol emissions for three months. A total of 15 compounds were detected, with monoterpene hydrocarbons and oxygenated monoterpenoids predominating. Only trans-p-menth-2-en-1-ol was common to all six symbionts. Peak levels of both isomers were observed at day 7, then gradually declined over a 90 day period. In choice tests, avocado sawdust disks inoculated with Fusarium sp. nov. were the most attractive. This symbiont produced only two volatiles, trans-p-menth-2-en-1-ol and limonene. The combined results indicate that trans-p-menth-2-en-1-ol is the primary female attractant emitted from symbiotic fungi, but limonene may be a secondary attractant of E. perbrevis.

Chemical Composition of Essential Oils from Leaves and Fruits of Juniperus foetidissima and Their Attractancy and Toxicity to Two Economically Important Tephritid Fruit Fly Species, Ceratitis capitata and Anastrepha suspensa.

The present study analyzed the chemical composition of Juniperus foetidissima Willd. essential oils (EOs) and evaluated their attractancy and toxicity to two agriculturally important tephritid fruit flies. The composition of hydrodistilled EOs obtained from leaves (JFLEO) and fruits (JFFEO) of J. foetidissima was analyzed by GC-FID and GC-MS. The main compounds were α-pinene (45%) and cedrol (18%) in the JFLEO and α-pinene (42%), α-thujone (12%), and ß-thujone (25%) in the JFFEO. In behavioral bioassays of the male Mediterranean fruit fly, Ceratitis capitata (Wiedemann), both JFLEO and JFFEO showed strong attraction comparable to that observed with two positive controls, Melaleuca alternifolia and Tetradenia riparia EOs. In topical bioassays of the female Caribbean fruit fly, Anastrepha suspensa (Loew), the toxicity of JFFEO was two-fold higher than that of JFLEO, with the LD50 values being 10.46 and 22.07 µg/µL, respectively. This could be due to differences in chemical components between JFLEO and JFFEO. The JFFEO was dominated by 48% monoterpene hydrocarbons (MH) and 46% oxygenated monoterpenes (OM), while JFLEO consisted of 57% MH, 18% OM, and 20% oxygenated sesquiterpenes (OS). This is the first study to evaluate the attractancy and toxicity of J. foetidissima EOs to tephritid fruit flies. Our results indicate that JFFEO has the potential for application to the management of pest tephritid species, and further investigation is warranted.

Insecticidal and Attractant Activities of Magnolia citrata Leaf Essential Oil against Two Major Pests from Diptera: Aedes aegypti (Culicidae) and Ceratitis capitata (Tephritidae).

In this study, Magnolia citrata Noot and Chalermglin (Magnoliaceae) essential oil (MCEO) was evaluated for insecticidal activity against the yellow fever mosquito Aedes aegypti and attractant activity for the Mediterranean fruit fly Ceratitis capitata. The leaves of Magnolia citrata (Gioi chanh) were collected from northwestern Vietnam, and the water-distilled MCEO was analyzed by gas-chromatography and mass spectrometry (GC-MS). The major constituents of MCEO were identified as linalool 19%, geranial 16%, citronellal 14%, neral 14%, and sabinene 12%. MCEO showed 100% mortality at 1 µg/µL against 1st instar larvae of Ae. aegypti (Orlando strain, ORL), and the oil exhibited 54% (ORL) and 68% (Puerto Rico strain) mortality at 5 µg/mosquito against Ae. aegypti adult females. Initial screens showed that MCEO had weak insecticidal activity compared to the positive control permethrin. In bioassays with sterile male C. capitata, MCEO exhibited moderately strong attraction, comparable to that observed with a positive control, Tetradenia riparia essential oil (TREO). Herein, the insecticidal and attractant activities of MCEO are reported for the first time.

Insecticidal Activity and Free Radical Scavenging Properties of Isolated Phytoconstituents from the Saudi Plant Nuxia oppositifolia (Hochst.).

Chromatographic purification of the alcoholic extract from the aerial parts of the Saudi plant Nuxia oppositifolia (Hochst.), Benth., resulted in five isolated phenolic compounds. Two flavones, hispidulin (1) and jaceosidin (2), and the phenylethanoid glycosides, verbascoside (3), isoverbascoside (4), and conandroside (5), were identified and their chemical structures were determined by spectroscopic analyses. The insecticidal activity of compounds 1 and 2, in addition to 11 compounds isolated in a previous research (6-16), was evaluated against the Yellow Fever mosquito, Aedes aegypti. Four compounds displayed adulticidal activity with LD50 values of 2-2.3 µg/mosquito. Free radical scavenging properties of the plant extracts and compounds (1-5) were evaluated by measuring the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate radical cation (ABTS•+) scavenging activity. All compounds exhibited notable activity, compared with the positive control, l-Ascorbic acid. This study suggests that N. oppositifolia could be a promising source of secondary metabolites, some with lethal adulticidal effect against Ae. aegypti.

TLC-Based Bioassay to Isolate Kairomones from Tea Tree Essential Oil That Attract Male Mediterranean Fruit Flies, Ceratitis capitata (Wiedemann).

The Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) poses a major threat to fruit and vegetable production in the United States and throughout the world. New attractants and detection methods could improve control strategies for this invasive pest. In this study, we developed a method that combined thin-layer chromatography (TLC) of tea tree essential oil (TTO) (Melaleuca alternifolia) with short-range bioassays to isolate attractive kairomones for male C. capitata. After development, the TLC chromatogram indicated that TTO separated into five major spots, designated as zones 1 to 5. When the TLC plate was exposed to flies, zones 1 and 3 were strongly attractive to male C. capitata. To confirm activity, the developed TLC plate was cut into five zones which were then tested in short-range bioassays. Again, flies were observed to aggregate around zones 1 and 3, which corresponded with Rf values of 0.93 and 0.59. In addition, zones 1 to 5 were separated using preparative-TLC, and olfactory responses to volatile emissions from the five fractions were quantified by electroantennography (EAG). Highest amplitude EAG responses were recorded with fractions 1 and 3, further supporting the bioactivity of these samples. In conclusion, a TLC-based bioassay system can provide an effective, rapid screening protocol for initial isolation of insect kairomones from complex mixtures such as essential oils or plant extracts. Further analysis of TTO fractions 1 and 3 is needed to identify the specific constituents attractive to male C. capitata.

Chemical Characterization and Biological Activity of the Mastic Gum Essential Oils of Pistacia lentiscus Var. Chia from Turkey.

The essential oils (EOs) were isolated by hydrodistillation from wild and cultivated Pistacia lentiscus L. var. chia-mastic gum tree (Anacardiaceae) from two natural habitats, namely from Cesme-Uzunkoy (1) and Mordogan (2), and one cultivated source, Cesme-Germiyan (3), in Izmir, Turkey. This comparative study evaluated the chemical composition and biological activity of mastic gum essential oils (MGEOs). For this purpose, MGEOs 1-3 were analyzed by gas chromatography-flame ionization detection (GC-FID), gas chromatography-mass spectrometry (GC-MS), and chiral GC for α-pinene. Laboratory assays were conducted to assess for potential in vitro cytotoxicity (multiple in vitro cancer cell lines), antimicrobial properties (five bacterial species and yeast), anti-inflammatory activity (inhibition of inducible nitric oxide synthase, iNOS), and the attraction of Ceratitis capitata (Mediterranean fruit fly, medfly), respectively. Chemical analysis indicated that MGEOs 1 and 2 were rich in α-pinene (56.2% and 51.9%), myrcene (20.1% and 18.6%), and ß-pinene (2.7% and 3.1%), respectively; whereas MGEO-3 was characterized by a high level of α-pinene (70.8%), followed by ß-pinene (5.7%) and myrcene (2.5%). Chiral GC analyses showed that concentration ratios between (-)/(+)-α-pinene and (-)-α-pinene/myrcene allowed for differentiation between wild and cultivated MGEO sources. In biological assays, MGEOs 1-3 did not exhibit significant antimicrobial effects against the pathogens evaluated and were not strong attractants of male medflies; however, all three MGEOs displayed a dose-dependent inhibition of iNOS, and MGEOs 1 and 2 exhibited selective in vitro cytotoxicity against human cancer cells. These results suggest that wild-type mastic gum oils from Cesme and Mordogan (MGEOs 1 and 2) are potential sources of beneficial products and warrant further investigation.

Insecticidal and Biting Deterrent Activities of Magnolia grandiflora Essential Oils and Selected Pure Compounds against Aedes aegypti.

In our natural products screening program for mosquitoes, we tested essential oils extracted from different plant parts of Magnolia grandiflora L. for their insecticidal and biting deterrent activities against Aedes aegypti. Biting deterrence of seeds essential oil with biting deterrence index value of 0.89 was similar to N,N-diethyl-3-methylbenzamide (DEET). All the other oils were active above the solvent control but the activity was significantly lower than DEET. Based on GC-MS analysis, three pure compounds that were only present in the essential oil of seed were further investigated to identify the compounds responsible for biting deterrent activity. 1-Decanol with PNB value of 0.8 was similar to DEET (PNB = 0.8), whereas 1-octanol with PNB value of 0.64 showed biting deterrence lower than 1-decanol and DEET. The activity of 1-heptanol with PNB value of 0.36 was similar to the negative control. Since 1-decanol, which was 3.3% of the seed essential oil, showed biting deterrence similar to DEET as a pure compound, this compound might be responsible for the activity of this oil. In in vitro A & K bioassay, 1-decanol with MED value of 6.25 showed higher repellency than DEET (MED = 12.5). Essential oils of immature and mature fruit showed high toxicity whereas leaf, flower, and seeds essential oils gave only 20%, 0%, and 50% mortality, respectively, at the highest dose of 125 ppm. 1-Decanol with LC50 of 4.8 ppm was the most toxic compound.

Chemical composition of the essential oil and n-hexane extract of Stachys tmolea subsp. Tmolea Boiss., an endemic species of Turkey, and their mosquitocidal activity against dengue vector Aesdes aegypti.

Stachys tmolea subsp. tmolea Boiss. is endemic to Turkey and is a species of the genus Stachys L. which is one of the largest genera of the family Lamiaceae with about 300 species. The aims of this study were to examine the chemical composition of the essential oil and n-hexane extract of S. tmolea subsp. tmolea as natural sources of insecticidal activity against the dengue vector, Aedes aegypti. Analysis of the essential oil by GC-FID and gas chromatography-mass spectrometry (GC-MS) systems identified hexahydrofarnesyl acetone (15%), viridiflorol (10%), hexadecanoic acid (7%) and 9-geranyl-p-cymene (6%) as major components. The volatile components of the n-hexane extract were extracted using headspace solid-phase microextraction (HS-SPME) and were analyzed using GC-MS. The principal constituents were 3,4-dimethyl decane (16%), 3-methyl-3-pentanol (15%), 2-methyl-2-pentanol (12%), 1,4-bis (1,1-dimethylethyl) benzene (12%), heptanal (10%), acetic acid (6%) and decane (4%). Bioassay of the n-hexane extract, at 5 µg/mosquito, produced 90% mortality against adult Ae. aegypti while the S. tmolea essential oil demonstrated 13% mortality. No larvicidal activity was observed both in essential oil and n-hexane extract. Further studies are needed to assess the adulticidal activity of the responsible compounds in the crude extract.

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.

Fungicidal Properties of Some Novel Trifluoromethylphenyl Amides.

Trifluoromethylphenyl amides (TFMPAs) were designed and synthesized as potential pesticides. Thirty-three structures were evaluated for fungicidal activity against three Colletotrichum species using direct bioautography assays. Active compounds were subsequently tested against C. fragariae, C. gloeosporioides, C. acutatum, Phomopsis obscurans, P. viticola, Botrytis cinerea and Fusarium oxysporum. The study identified 2-chloro-N-[2,6-dichloro-4-(trifluoromethyl)phenyl]acetamide (7a) as showing the strongest antifungal activity, and the broadest activity spectrum in this set against Colletotrichum acutatum (at 48 and 72 h) and Phomopsis viticola (at 144 h). The presence of triethylamine in its complex with N-[2,6-dichloro-4-(trifluoromethyl)phenyl]-2,2,3,3,3-pentafluoropropanamide (7b') played an important role in the bioactivity, and depending on the concentration or fungal species it showed higher or lower activity than the parent amide. X-Ray crystallography has shown that the complex (7b') is an ion pair, (C10 H2 Cl2 F8 NO)- (C6 H16 N)+ , where a proton is transferred from the amide nitrogen to the triethylamine nitrogen and then connected by hydrogen bonding to the acyl oxygen (N-H 0.893 Å; H⋅⋅⋅O 1.850 Å; N⋅⋅⋅O 2.711 Å; N-H⋅⋅⋅O 161.2(13)°). Although none of these compounds were better than standards, this work revealed some potential lead structures for further development of active novel compounds.

Chemical composition and antioxidant, cytotoxic, and insecticidal potential of Valeriana alliariifolia in Turkey.

Valeriana is a common plant species used for various healing purposes in folk medicine since antiquity. This study investigates the phytochemical profile, antioxidant, cytotoxic, and insecticidal activity of Valeriana alliariifolia Adams, a species that has traditionally been used in Turkey. For the analyses we prepared four root extracts of V. alliariifolia Adams using hexane (HM1), chloroform (CM1), ethanol (EM1), and water (WM1) for maceration. Additionally, two extracts were also prepared from its roots by maceration separately with ethanol (EM2) and water (WM2). One sample was prepared as a water infusion (WI), according to the procedure used in Turkish traditional medicine. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation scavenging activity tests showed that ethanol extracts had the strongest antioxidant activity: EM1 (IC50 - DPPH: 17.694 µg/mL; ABTS: 23.8 µg/mL) and EM2 (IC50 - DPPH: 20 µg/mL; ABTS: 21.5 µg/mL). The hexane extract, HM1, was the most cytotoxic (IC50<10 µg/mL against HepG2 and HUVEC) and EM2 strongly cytotoxic (IC50<10 µg/mL against HepG2 and IC50: 11.96 µg/mL against HUVEC). The extracts with demonstrated cytotoxic activities were further examined to check their insecticidal activity against adult female mosquito Aedes aegypti and first instar Ae. aegypti larvae. HM1 was the most effective (90±10 %), which was consistent with its cytotoxic activity. Because of the high antioxidant, cytotoxic, and insecticidal activities, we ran phytochemical analyses of the HM1, EM1, and EM2 extracts with GC-MS (for HM1) and LC-MS/MS (for EM1 and EM2). We also analysed the composition of the essential oil obtained from V. alliariifolia roots by micro-distillation in order to compare its content with HM1, which contains volatile compounds. Phytochemical analyses revealed that the major compound in HM1 was isovaleric acid (16 %) and in the essential oil 1,8-cineole (2.9 %). EM1 and EM2 contained 5-O-caffeoylquinic acid (chlorogenic acid), verbascoside (acteoside), and 3,5-dicaffeoylquinic acid as major components. In the light of our findings and available literature, we can conclude that V. alliariifolia has a good bioactive potential that could be used for different purposes, including the development of new agents for the treatment of various diseases. The difference in the content between the essential oil and HM1 was remarkable. It suggests that the variability observed in the activity of the samples was a result of composition and that, therefore, the aim of treatment should dictate which type of preparation is to be selected. An added value of our study is that it determined verbascoside and methylquercetin rutinoside for the first time in the Valeriana extracts.