Thirty-four plant essential oils were screened for their acaricidal and oviposition deterrent activities against two-spotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae), in the laboratory using a leaf-dip bioassay. From initial trials, sandalwood and common thyme oils were observed to be the most effective against TSSM adult females. Subsequent trials confirmed that only sandalwood oil was significantly active (87.2 ± 2.9% mortality) against TSSM adult females. Sandalwood oil also demonstrated oviposition deterring effects based on a 89.3% reduction of the total number of eggs on leaf disks treated with the oil. GC-MS analysis revealed that the main components of the sandalwood oil were α-santalol (45.8%), β-santalol (20.6%), β-sinensal (9.4%), and epi-β-santalol (3.3%). A mixture of α- and β-santalol (51.0:22.9, respectively) produced significantly higher mortality (85.5 ± 2.9%) and oviposition deterrent effects (94.7% reduction in the number of eggs) than the control. Phytotoxicity was not shown on rose shoots to which a 0.1% solution of sandalwood oil was applied.

A tool for integrated pest management is the use of essential oils (EOs) and plant extracts. In this study, EOs from Tagetes lucida , Lepechinia betonicifolia , Lippia alba , Cananga odorata , and Rosmarinus officinalis , species grown in Colombia, were analyzed by gas chromatography-mass spectrometry. These oils as well as several of their constituents were tested for repellent activity against Tribolium castaneum , using the area preference method. The main components (>10%) found in EOs were methylchavicol, limonene/α-pinene, carvone/limonene, benzyl acetate/linalool/benzyl benzoate, and α-pinene, for T. lucida, L. betonicifolia, L. alba, C. odorata, and R. officinalis, respectively. All EOs were repellent, followed a dose-response relationship, and had bioactivity similar to or better than that of commercial compound IR3535. EOs from C. odorata and L. alba were the most active. Compounds from EOs, such benzyl benzoate, β-myrcene, and carvone, showed good repellent properties. In short, EOs from plants cultivated in Colombia are sources of repellents against T. castaneum.

CONTEXT Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. In this context, essential oils have received much attention as potentially useful bioactive compounds against insects. Therefore, our present study aimed to evaluate the efficacy of essential oils from the aerial parts of Salvia elegans Vahl, Salvia dorisiana Standl., Salvia splendens Sello ex J.A. Schult Blue Ribbon, and S. splendens Sello ex J.A. Schult Scarlet Sage Red (Lamiaceae) against the fourth instar larvae of Aedes albopictus Skuse (Diptera: Culicidae). OBJECTIVE The mosquito larvicidal activities of the essential oils and chemical composition of four taxa of Salvia are investigated in this article for the first time. MATERIALS AND METHODS Chemical compositions of essential oils obtained from four taxa of Salvia were analyzed by gas chromatography-mass spectrometry (GC-MS), GC-FID, and the effects of essential oils on fourth instar larvae of A. albopictus were investigated. RESULTS The main components identified from each Salvia essential oils were as follows: spathulenol (38.73%) and caryophyllene (10.32%) from S. elegans; ledol (45.8%) and 4,4'-[(p-phenylene)diisopropylidene]diphenol (17.38%) from S. dorisiana; β-cubebene (22.9%), and caryophyllene (12.99%) from S. splendens Blue Ribbon; phytol (41.46%) and cyclooctasulfur (24.88%) from S. splendens Scarlet Sage Red. The essential oils of S. elegans and S. splendens Blue Ribbon had excellent inhibitory larvicidal effect against A. albopictus larvae, and their LC(50) values in 24 h were 46.4 ppm (LC(90) = 121.8 ppm) and 59.2 ppm (LC(90) = 133.0 ppm), respectively. DISCUSSION AND CONCLUSION These findings demonstrate that the essential oils of these Salvia species could be considered as the powerful candidates to bring about useful botanicals so as to prevent the resurgence of mosquito vectors.

The larvicidal activity of 18 phenylpropanoids, 1-18, including phenylpropenoate, phenylpropenal, phenylpropene, and their semisynthetic analogues, were evaluated against the tobacco armyworm, Spodoptera litura (Fab.), to identify promising structures with insecticidal activity. Amongst various phenylpropanoids, isosafrole, a phenylpropene, showed the best activity, with an LC(50) value of 0.6 microg/leaf cm(2), followed by its hydrogenated derivative dihydrosafrole (LC(50)=2.7 microg/leaf cm(2)). The overall larvicidal activity of various phenylpropene derivatives was observed in the following order: isosafrole (6)>dihydrosafrole (16)>safrole (12)>anethole (4)>methyl eugenol (11)>eugenol (13)>beta-asarone (8)>dihydroasarone (18)>dihydroanethole (15). Dihydrosafrole might be a promising compound, although presenting a lower larvicidal activity than isosafrole, because of its better stability and resistance to oxidative degradation (due to the removal of the extremely reactive olefinic bond) in comparison to isosafrole. Such structure-activity relationship studies promote the identification of lead structures from natural sources for the development of larvicidal products against S. litura and related insect pests.

Oil samples from four chemotypes of Thymus vulgaris were tested for mosquitocidal activity. Oil compounds were analyzed by gas chromatography-mass spectrometry (GC-MS). The different compositions of the oils varied in their biological activity as well. Larvicidal efficiency was determined for the most significant oil thymol type (T), namely the lowest doses LD(50) 32.9 and 14.2 mg/l for the third and fourth instars, respectively. The oils also showed very good efficiency with respect to mortality and to the percentage of adult emergence upon short-term exposure in water treated by lethal doses of individual oils. Although the larvae were left in treated water for only 5 h, mortality corresponding to LD(50) was determined after 24 h, i.e., between 49% and 63%. Furthermore, mortality increased significantly in relation to time of exposure, and total mortality of the larvae at the end of their development was about 90%. Such significant mortality was also naturally reflected in the total emergence of adults. In the control sample, there was 77% adult emergence from the larvae, whereas in oils, there was only from 5.3% to 16% emergence. The greatest fumigate efficiency was found for T and linalool chemotypes, with an LC(50) for 24 h of exposure being 1.1 and 1.8 mg/l, respectively. Essence T was also most efficient in the tarsal test, with LD(50) of 44 mug/cm(2) and LD(90) of 63 mug/cm(2). High antioviposition efficiency was found in all tested oils.

A screening for larvicidal activity of plant extracts with some known medicinal attributes could lead to the discovery of new agents for pest and vector control. In the backdrop of recent revival of interest in developing plant-based insecticides, the present study was carried out to evaluate the larvicidal properties in three medicinal plants growing abundantly in the region of Chitheri Hills, Dharmapuri District, India. Antifeedant and larvicidal activity of the acetone, chloroform, ethyl acetate, hexane and methanol leaf extracts of Ocimum canum, Ocimum sanctum and Rhinacanthus nasutus were studied against fourth instar larvae of Spodoptera litura (Lepidoptera: Noctuidae), Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae). The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in methanol extract of O. canum, R. nasutus and acetone extract of O. sanctum against the larvae of S. litura (LC(50)= 36.46, 68.08 and 68.84 ppm), against A. aegypti (LC(50)= 99.42, 94.43 and 81.56 ppm) and against C. quinquefasciatus (LC(50)= 44.54, 73.40 and 38.30 ppm), respectively. This is an ideal eco-friendly approach for the control of the agricultural pest, S. litura, and medically important vectors, A. aegypti and C. quinquefasciatus.

Kahramanmaras, is a developing city located in the southern part of Turkey Thymus eigii (M. Zohary and RH. Davis) Jalas, Pinus nigraAm. sub sp pallasiana and Cupressus sempervirens L. are the useful plants of the Kahramanmaras province and have been understudy since 2004 for the traditional uses of plants empiric drug, spice, herbal tea industry herbal gum and fuel. The study was designed to examine the antimicrobial activities of essential oils of these plants by the disc diffusion and minimum inhibitory concentration (MIC) methods. In addition, antimicrobial activity of Thymus eigii was researched by effects when it was used together with antibiotics and even when it was combined with other essential oils. When the results of this study were compared with vancomycin (30 mcg) and erytromycin (15 mcg) standards, it was found that Thymus eigii essential oil was particularly found to possess strongerantimicrobial activity whereas other essential oils showed susceptible or moderate activity However, antimicrobial activity changed also by in vitro interactions between antibiotics and Thymus eigii essential oil, also between essential oils of these plants and that of Thymus eigii causing synergic, additive, antagonist effect.

Extracts of Capparis decidua stems and flowers showed insecticidal and oviposition inhibitory activities against Bruchus chinensis. The LC50 values of these extracts were found to increase with the increase in the polarity of the extract at different exposure periods. For instance, after 96 h, the LC50 values were found to be 3.619, 7.319, and 10.151 microg for CD1, CD2, and CD3, respectively. Extract CD7 was effective only at higher doses. The toxicity was found to be dose- and time-dependent. The females laid lesser number of eggs, when exposed to sublethal doses of different extracts and pure compounds, as compared to control. The maximum oviposition deterrence index was found for extract CD1 followed in decreasing order by CD2, CD3, and CD7. From extract CD1, two compounds were isolated and characterized as triacontanol (C1) and 2-carboxy-1,1-dimethylpyrrolidine (C2). When the females were exposed to sublethal doses of these compounds, they laid lesser number of eggs as compared to the control. C2 was found to have a slightly greater oviposition inhibition effect than C1. From fraction CD7, one novel compound labeled as CDF1 has been isolated and identified as 6-(1-hydroxy-non-3-enyl)tetrahydropyran-2-one. CDF1 has also shown insecticidal and oviposition inhibitory activities against B. chinensis at low concentrations.

Ethanol extracts of the aerial parts from five Labiatae (Lamiaceae) species, obtained from Antalya, Turkey, were tested for larvicidal activity against the house mosquito Culex pipiens L.(Diptera: Culicidae) under laboratory conditions. Third and fourth instar mortality from six concentrations (5, 10, 25, 50, 100 and 200 ppm) of each plant extract were compared against the organophosphorus insecticide, temephos which is currently used for larval control. All plant extracts showed high larvicidal activity in 24 h exposure tests. Teucrium divaricatum Sieber was the most toxic, followed by Mentha longifolia (L.) Huds., Melissa officinalis L., Salvia sclarea L. and Mentha pulegium L. with LC(50) values of 18.6, 26.8, 39.1, 62.7 and 81.0 ppm, respectively. This study is the first to report on the larvicidal activity of ethanol extracts of these five plant species against C. pipiens.

The insecticidal activity of essential oils isolated from two species of Origanum (Origanum onites L. and Origanum minutiflorum (O. Schwarz and P.H. Davis)(Labiate)) was investigated against 3rd and 4th instar larvae of the mosquito, Culex pipiens L.(Diptera: Culicidae). The LC50 and LC90 values were 24.8 and 61.3 ppm, and 73.8 and 118.9 ppm, respectively. This activity was attributed to the carvacrol, the major constituent of these oils.

The genus Erythrina (Leguminosae), consisting of over 100 different species, is distributed in tropical regions. In traditional medicine, Erythrina species are used to treat cancer, but little is known about the anticancer mechanisms. From the stem bark of Erythrina addisoniae Hutch.& Dalziel, six prenylated pterocarpans were isolated and analysed for pharmacological activity: While calopocarpin, cristacarpin, orientanol c, and isoneorautenol showed only a weak or moderate toxicity in H4IIE hepatoma cells (EC(50)-value>25muM), the toxicity of neorautenol and phaseollin was in the low micromolar range (EC(50)-value: 1 and 1.5muM, respectively). We further focused on these two substances showing that both increased caspase 3/7 activity and nuclear fragmentation as markers for apoptotic cell death. Neorautenol (10muM, 2h), but not phaseollin induced the formation of DNA strand breaks (comet assay). Both substances showed no effect on NF-kappaB signalling (SEAP assay: basal activity and stimulation with TNF-alpha), on the other hand both pterocarpans (10muM, 2h) decreased the activation of the ERK kinase (p44/p42), an mitogen activated protein kinase which is associated with cell proliferation. We conclude that the pterocarpans phaseollin and neorautenol may be responsible for the anticarcinogenic actions of the plant extract reported in the literature. Further analysis of these substances may lead to new pharmacons to be used in cancer therapy.

Leaves of NEUROLAENA LOBATA (L.) R. Br. originating from Guatemala, were analyzed using HPLC for their qualitative and quantitative sesquiterpene lactone contents. Significant differences in the individual amounts of neurolenins and furanoheliangolides were found between four natural populations. When plants were cultivated on proving fields at two different localities in Guatemala, their sesquiterpene lactone patterns matched the natural population, but differed quantitatively. The meaning of these differences for the use of N. LOBATA in traditional medicine and its cultivation is discussed.

The flowers of A. AMPLEXICAULIS afforded, in addition to xanthalongin ( 1), 11beta,13-dihydroxanthalongin ( 2), its 11-epimer ( 3), and 11alpha,13-dihydro-4 H-xanthalongin ( 4), the new xanthanolide glycosides 11alpha, 13-dihydro-4 H-xanthalongin 4- O-beta- D-glucopyranoside ( 5) and its 11-epimer ( 6). The glycosides were also isolated from the flowers of A. MOLLIS. The structures were elucidated by NMR spectroscopy (1)H-NMR, COSY,(13)C-NMR, HETCOR, DEPT), MS (EI, FAB, FD), and enzymatic hydrolysis of the glycosides. The chemo-taxonomic importance is discussed.

Chemosensory proteins (CSPs) are associated with insect sensory organs, including the sensillum lymph in some cases. However, they are also commonly expressed in nonsensory tissues that lack gustatory and olfactory neurones. We characterized the sex and development specific expression patterns of four CSP genes from the Eastern spruce budworm (ESB) using Northern blots. CfumAY426540.2 was detected at high levels in adult moths. Conversely, CfumAY426538 was expressed in all stages except adult moths, and was most abundant during late stages of the 6th instar. CfumAY701858 was expressed in all stages, while CfumAY426539 was detected less frequently, at specific developmental stages such as the 5th to 6th instar moult. During a natural moult, and a premature moult induced by the ecdysteroid agonist tebufenozide, CfumAY701858 and CfumAY426539 were up-regulated, while CfumAY426538 appeared to be down-regulated. Our results suggest that some members of the CSP gene family from the ESB may be involved in development, including moulting.

The efficacy of extracts from two Piperaceae species, Piper nigrum L. and P. tuberculatum Jacq. were evaluated using larvae and adults of the Colorado Potato Beetle Leptinotarsa decemlineata (Say). Young larvae and neonates were the most susceptible; a 24-h LD(50) of 0.064% extract of P. tuberculatum was determined for 4-day-old larvae, while 0.05% extract of P. nigrum reduced larval survival up to 70% within one week after treatment of potato Solanum tuberosum L.(Solanaceae) plants. When an insecticide resistant strain of L. decemlineata larvae was tested with the P. tuberculatum extract, there was less than a 2-fold tolerance ratio compared to the 22-fold tolerance ratio to cypermethrin, a pyrethroid. Older larvae, pre-pupal stage and adults, were less sensitive to the P. nigrum extracts; the 24-h LD(50) was 0.5%(95% C.I.= 0.36, 0.65). However, the same concentration was equally effective under field conditions. In the greenhouse, P. nigrum at 0.5% was as effective at reducing adult L. decemlineata feeding as combinations with 2 separate botanical mixtures, garlic and lemon grass oil. Under field conditions, the residual activity of the P. nigrum extracts was less than 3 h. When adult L. decemlineata were placed on treated plants exposed to full sunlight for 0, 1.5, and 3 h, leaf damage progressively increased as the main active compound, piperine, was found to degrade by 80% after 3 h. An in vitro polysubstrate monoxygenase (PSMO) enzyme assay, using the substrate methoxyresorufin O-demethylation (MROD), determined that the principal P. nigrum active compound, piperine, is responsible for inhibition of that specific enzyme. The results suggest that Piper extracts could be used effectively as contact botanical insect control agents to protect potato plants from developing L. decemlineata larvae at concentrations less than 0.1%. There is also potential for Piper extracts to control insecticide resistant populations in conjunction with other integrated pest management (IPM) strategies used in conventional and organic agriculture. Arch. Insect Biochem. Physiol. 54:212-225, 2003.

Extracts, fractions and sesquiterpene lactones from Neurolaena lobata (L.) R. Br.(Asteraceae), a traditional medicinal plant from Guatemala, were tested in vitro against Leishmania spp. promastigotes, Trypanosoma cruzi trypomastigotes and epimastigotes and Trichomonas vaginalis trophozoites. The ethanol extract inhibited the parasite growth of L. mexicana, T. cruzi and T. vaginalis significantly. The pure germacranolides 1 and a mixture of 2 and 3, isolated from the ethonal extract, were highly active against L. mexicana and T. cruzi.

Monoterpenoids (terpenes and biogenically related phenols) commonly found in plant essential oils were tested for acute toxicity via topical application to tobacco cutworms (Spodoptera litura Fab.). The most toxic among 10 such compounds was thymol (LD(50)= 25.4 microg/larva) from garden thyme, Thymus vulgaris. The compounds were then tested for sublethal effects, specifically inhibition of larval growth after topical application of low doses. Among 6 compounds tested, an LD(10) dose reduced growth by 20% on average 3 days after administration. Feeding deterrence was determined using a cabbage leaf disk choice test. The most deterrent compound was thymol, with a DC(50) of 85.6 microg/cm(2) leaf disk area. Because minor constituents in complex essential oils have been suggested to act as synergists, binary mixtures of the compounds were tested for synergy vis à vis acute toxicity and feeding deterrence. trans-Anethole acted synergistically with thymol, citronellal, and alpha-terpineol, in terms of both acute toxicity and feeding deterrence. On the basis of these findings, several complex mixtures were developed and tested as leads for effective control agents. Candidate mixtures demonstrated good synergistic effects. The observed LD(50) of mixture 3 was 40.6 microg/larvae compared to an expected value of 74.6 microg/larvae. The result of this research is a proprietary product suitable for commercial production.

Six sesquiterpene lactones, two new (3 and 6) and four known (1, 2, 4 and 5) were isolated from the leaves of the Mexican Neurolaena macrocephala (Asteraceae). The furanoheliangolide 6, containing 4beta,5-dihydro-9alpha-hydroxy-atripliciolide as basic structure, was found for the first time in nature. The chemotaxonomic importance of this phytochemical work is discussed.

Ninety-two plants used in the traditional pharmacopoeia of the Pech and neighboring Mestizo peoples of central Honduras are reported. The results of in vitro antimicrobial screens showed that 19 of the extracts from medicinal plants revealed signs of antifungal activity while 22 demonstrated a measurable inhibitory effect on one or more bacterial cultures. Bioassay-guided fractionation of extracts from Mikania micrantha, Neurolaena lobata and Piper aduncum produced weak to moderately active isolates. The broad spectrum of activity of the extracts helps to explain the widespread use of these plants for wound healing and other applications.

1. Sodium soaps prepared from olive oil, croton oil, cod-liver oil, linseed oil, etc., have the property of inhibiting the action of trypsin and leucoprotease. 2. The activity of these soaps is dependent upon the degree of unsaturation of the fatty acids and is in proportion to their iodin value. 3. Saturation of the acids with a halogen (iodin) causes a loss of this property. 4. Soaps of the saturated fatty acids tested do not have this influence on ferments.

The essential oil composition of the aerial parts of Anaphalis nubigena DC. var. monocephala (DC.) C. B. Clarke collected from Pindari glacier at a height of 3300 m, was analyzed by using GC and GC/MS. Sixty components were identified, accounting for 95.9% of the total oil. The main constituents were alpha-guaiene (12.3%), gamma-muurolene (10.4%), gamma-cadinene (8.3%), alpha-muurolol (7.4%), alpha-gurjunene (6.0%) and alpha-bulnesene (5.8%). The oil was found to be rich in sesquiterpene hydrocarbons (60.1%). The oil was active against Escherichia coli (NCIM 2065) and Klebsiella pneumoniae (NCIM 2957), with MIC values of 125 microg/mL and 500 microg/mL, respectively.

The acaricidal effects of the volatile essential oil Origanum minutiflorum O. Schwarz & P.H. Davis (Lamiaceae) against adult Rhipicephalus turanicus was evaluated at a variety of concentrations and exposure times. Generally tick mortality increased with concentration and exposure. Ticks exposed to vapors from cotton wicks containing at least 10mul/L resulted in complete (100%) mortality at 120min. The major constituent of essential oil obtained from the plant material of O. minutiflorum was carvacrol.

The essential oil of Elephantopus scaber, a famous medicinal herb from Yangjiang County in Southern China was analyzed for the first time using GC-MS. The major constituents were hexadecanoic acid (42.3%), isopropyl dimethyl tetrahydronaphthalenol (14.1%), beta-sesquiphellandrene (8.3%), octadecadienoic acid (5.5%), and phytol (5.2%).

The Casimiroa pringlei essential oil was analyzed to determine its chemical composition. Its effect on rat uterine smooth muscle was studied and compared with verapamil. Pure commercial piperitone, eucalyptol, and alpha-terpineol, the major constituents of C. pringlei essential oil, were tested on the uterine tonic contraction induced by high-potassium depolarizing solution (KCl 60 mM).

This study was designed to examine the chemical composition of essential oil and the in vitro antimicrobial activities of essential oil and methanol extract of Teucrium montanum. The inhibitory effects of essential oil and methanol extracts of T. montanum were tested against 13 bacterial and three fungal species by using disc-diffusion method. GC/MS analyses revealed that essential oil contains mainly delta-cadinene (17.19%), beta-selinene (8.16%) alpha-calacorene (4.97%), 1,6-dimethyl-4-(1-methylethyl)-naphthalene (4.91%), caryophyllene (4.35%), copaene (4.23%), torreyol (3.91%), 4-terpineol (3.90%), cadina-1,4-diene (3.39%), beta-sesquiphellandrene (3.34%), tau-cadinol (3.12%) and gamma-curcumene (3.18%). The essential oil has antibacterial as well as antifungal effect.

The essential oil obtained from the seeds of Momordica charantia was analyzed by GC/MS. Twenty-five components, representing 90.9% of the oil, were identified. The main constituents were trans-nerolidol, apiole, cis-dihydrocarveol and germacrene D. Furthermore, the oil was tested for its antibacterial and antifungal activities. Staphylococcus aureus was found to be the most sensitive microorganism with MIC values <500 mug/ml.

Dillapiol was isolated from the essential oil of dill as a specific inhibitor of aflatoxin G1 production. It inhibited aflatoxin G1 production by Aspergillus parasiticus with an IC50 value of 0.15 microM without inhibiting aflatoxin B1 production or fungal growth. Apiol and myristicin, congeners of dillapiol, showed similar activity with IC50 values of 0.24 and 3.5 microM, respectively.

Composition of the water-distilled oil of the aerial parts of Centaurea aladagensis, endemic in Turkey, was analysed by GC-MS. Hexadecanoic acid (39.3%), caryophyllene oxide (6.6%) and hexahydrofarnesyl acetone (4.3%) were found as main constituents in the oil. The oil was tested against 7 human pathogenic microorganisms.

THYMUS SERPYLLOIDES ssp. GADORENSIS is endemic in the Betic region (Spain). Gas chromatography and GC/mass spectrometry studies of its essential oil showed its major components to be carvacrol and its biosynthetic precursors (gamma-terpinene and P-cymene).