Insecticidal Activities and Chemical Composition of the Essential Oils of Ajania nitida and Ajania nematoloba from China.

In this work, we investigated insecticidal and repellent activities of the essential oils extracted from Ajania nitida and Ajania nematoloba against Tribolium castaneum and Lasioderma serricorne adults. The components of essential oils were analyzed by GC-MS. The main components of A. nitida oil were camphor (20.76%), thujone (18.64%), eucalyptol (13.42%), borneol (8.32%) and those of A. nematoloba oil were ß-pinene (34.72%), eucalyptol (24.97%) and verbenol (20.39%). The results showed that the two essential oils possessed insecticidal and repellent activities against two species of insects. A. nitida oil possessed contact and fumigant toxicity against T. castaneum (LD50 = 30.10 µg/adult and LC50 = 21.07 mg/L air) and L.serricorne (LD50 = 17.51 µg/adult and LC50 = 11.23 mg/L air). A.nematoloba oil showed contact and fumigant toxicity against T. castaneum (LD50 = 102.29µg/adult and LC50 = 69.45 mg/L air) and contact toxicity against L.serricorne (LD50 = 53.43 µg/adult), but no obvious fumigant effect was observed against L.serricorne. Both of essential oils possessed strong repellent activity against T. castaneum and certain repellent activity against L.serricorne. Especially, A. nematoloba oil showed the same level percentage repellency as DEET(the positve control) against T. castaneum. The results indicated that the essential oils of A. nitida and A. nematoloba had the potential to be developed as natural insecticides and repellents for the control of T. castaneum and L.serricorne.

Fumigant and repellent activities of essential oil extracted from Artemisia dubia and its main compounds against two stored product pests.

The major chemical constituents of the essential oil extracted from Artemisia dubia wall. ex Bess. (Family: Asteraceae) were found as terpinolene (19.02%), limonene (17.40%), 2,5-etheno[4.2.2]propella-3,7,9-triene (11.29%), isoelemicin (11.05%) and p-cymene-8-ol (5.93%). Terpinolene and limonene were separated as main components from the essential oil. The essential oil showed fumigant toxicity against Tribolium castaneum and Liposcelis bostrychophila with LC50 values of 49.54 and 0.74 mg/L, respectively. The essential oil and isolated compounds of A. dubia showed repellency activities against both insects. Terpinolene and limonene showed the fumigant toxicity against T. castaneum. Terpinolene showed obvious fumigant toxicity against L. bostrychophila. The results indicated that the essential oil of A. dubia had potential to be developed into natural insecticides for controlling stored product pests.

Repellent activity of essential oils extracted from five Artemisia species against Tribolium castaneum (Coleoptera: Tenebrionidae) / Actividad repelente de aceites esenciales extraídos de cinco especies de Artemisia contra Tribolium castaneum (Coleoptera: Tenebrionidae)

Artemisia genus (family Asteraceae) has been widely used as medicines and cosmetic. The chemical compositions of essential oils extracted from five Artemisia species (A. anethoides, A. giraldii, A. roxburghiana, A. rubripes and A. sacrorum) were analyzed and the repellent activities of five essential oils were investigated by testing percent repellency (PR) in petri dish against Tribolium castaneum. By GC-MS analysis, the common components of the five essential oils were eucalyptol (11.09%-50.05%), camphor (6.28%-33.10%), terpinen- 4-ol (2.46%-12.41%), ß-caryophyllene (0.63%-10.68%) and germacrene D (2.28%-10.01%). 3,3,6-trimethyl-1,4-heptadien-6-ol (11.72%), 2-isopropyl-5-methyl-3-cyclohexen-1-one (24.80%) and ß-farnesene (12.23%) were the characteristic compounds in essential oils of A. sacrorum, A. anethoides and A. rubripes respectively. The essential oils of five plants showed repellent activity against T. castaneum. The PR of others four essential oils were comparable with DEET expect for A. sacrorum. The results indicated that the essential oils of A. anethoides, A. giraldii, A. roxburghiana and A. rubripes had the potential to be developed as repellent for control of T. castaneum.

El género Artemisia (familia Asteraceae) ha sido ampliamente utilizado como medicamentos y cosméticos. Se analizaron las composiciones químicas de los aceites esenciales extraídos de cinco especies de Artemisia (A. anethoides, A. giraldii, A. roxburghiana, A. rubripes y A. sacrorum) y se investigaron las actividades repelentes de cinco aceites esenciales mediante la prueba de repelencia porcentual (PR) en placa de petri contra Tribolium castaneum. Por análisis GC-MS, los componentes comunes de los cinco aceites esenciales fueron eucaliptol (11,09% -50,05%), alcanfor (6,28% -33,10%), terpinen-4-ol (2,46% -12,41%), ß-cariofileno 0,63% -10,68%) y germacrén D (2,28% -10,01%). 3,3,6-trimetil-1,4-heptadien-6-ol (11,72%), 2-isopropil-5-metil-3-ciclohexen-1-ona (24,80%) y ß-farneseno (12,23%). Los compuestos característicos en los aceites esenciales de A. sacrorum, A. anethoides y A. rubripes respectivamente. Los aceites esenciales de cinco plantas mostraron actividad repelente contra T. castaneum. El PR de otros cuatro aceites esenciales eran comparables con DEET esperado para A. sacrorum. Los resultados indicaron que los aceites esenciales de A. anethoides, A. giraldii, A. roxburghiana y A. rubripes tienen el potencial de ser desarrollados como repelentes para el control de T. castaneum.

Chemical Constituents of Murraya tetramera Huang and Their Repellent Activity against Tribolium castaneum.

Sixteen compounds were isolated from the leaves and stems of Murrayatetramera Huang. Based on the NMR and MS spectral results, the structures were determined. It was confirmed that the isolated compounds included three new compounds (9, 10 and 13) and one new natural product (8), which were identified asmurratetra A (9), murratetra B (10), murratetra C (13) and [2-(7-methoxy-2-oxochromen-8-yl)-3-methylbut-2-enyl]3-methylbut-2-enoate (8), respectively. Meanwhile, the repellent activity against Tribolium castaneum was investigated for 13 of these isolated compounds. The results showed that the tested compounds had various levels of repellent activity against T. castaneum. Among them, compounds 1 (4(15)-eudesmene-1ß,6α-diol), 11 (isoferulic acid) and 16 (2,3-dihydroxypropyl hexadecanoate) showed fair repellent activity against T. castaneum. They might be considered as potential leading compounds for the development of natural repellents.

Bioactivities and Chemical Constituents of Essential Oil Extracted from Artemisia anethoides Against Two Stored Product Insects.

The chemical constituents of the essential oil extracted from Artemisia anethoides and the bioactivities of essential oil against Tribolium castaneum and Lasioderma serricorne were investigated. The main components of the essential oil were 1,8-cineole (36.54%), 2-isopropyl-5-methyl-3-cyclohexen-1-one (10.40%), terpinen-4-ol (8.58%), 2-isopropyltoluene (6.20) and pinocarveol (5.08%). The essential oil of A. anethoides possessed contact and fumigant toxicities against T. castaneum adults (LD50 = 28.80 µg/adult and LC50 = 13.05 mg/L air, respectively) and against L. serricorne (LD50 = 24.03 µg/adult and LD50 = 8.04 mg/L air, respectively). The crude oil showed repellent activity against T. castaneum and L. serricorne. Especially, the percentage repellency of essential oil was same level with DEET (positive control) against T. castaneum. The results indicated that the essential oil of A. anethoides had the potential to be developed as insecticide and repellent for control of T. castaneum and L. serricorne.

Repellence of the main components from the essential oil of Glycosmis lucida Wall. ex Huang against two stored product insects.

A screening of Chinese medicinal herbs and wild plants for agrochemicals was carried out; the essential oil of Glycosmis lucida leaves was found to possess significant repellent activity against Tribolium castaneum and Liposcelis bostrychophila. It was found that the main components included elixene (19.81%), spathulenol (10.68%), anethole (12.05%), verbenone (10.32%) followed by ß-caryophyllene (6.87%). The essential oil, anethole and verbenone were strongly repellent against T. castaneum (96, 86 and 94%, respectively, at 15.73 nL cm-2) and L. bostrychophila (100, 68 and 72%, respectively, at 31.58 nL cm-2) after a 2h treatment. The results indicate that anethole and verbenone had the potential to be developed as natural repellents for control of stored product insects.

Chemical Composition of Essential Oils from Zanthoxylum bungeanum Maxim. and Their Bioactivities against Lasioderma serricorne.

Two essential oil samples were obtained from the pericarp of Zanthoxylum bungeanum with the methods of hydrodistillation (HD) and supercritical fluid CO2 extraction (SFE), their chemical components were identified, and their bioactivities against Lasioderma serricorne adults were evaluated. In the process of testing, the two samples showed significant bioactivities against Lasioderma serricorne adults. For an example, the SFE-sample expressed relatively stronger fumigant toxicity on Lasioderma serricorne adults (LC50 = 3.99 µg/mL air) than that of the HD-sample (LC50 = 12.54 µg/mL air). According to GC-MS analysis, the chemical components between two samples were different. The major chemical components for HD included linalool (25.99%), limonene (19.34%), linalyl anthranilate (12.22%), 4-terpinenol (10.49%), eucalyptol (6.53%) and α-terpineol (5.02%), while for SFE included nonanoic acid (21.43%), γ-terpinene (14.51%), eucalyptol (13.45%), α-terpineol (5.83%) and caryophyllene oxide (5.48%). The results showed that different chemical components result in different bioactivities. This work provides theoretical basis for traditional Chinese concept of antagonistic storage, and it also provides important information for the development and comprehensive utilization of Zanthoxylum bungeanum.

Essential Oil of Amomum maximum Roxb. and Its Bioactivities against Two Stored-Product Insects.

Amomum maximum Roxb. is a perennial herb distributed in South China and Southeast Asia. The objective of this work was to analyze the chemical constituents and assess insecticidal and repellent activities of the essential oil from Amomum maximum fruits against Tribolium castaneum (Herbst) and Liposcelis bostrychophila (Badonnel). The essential oil was obtained by hydrodistillation and analyzed by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. The main components of the essential oil were identified to be ß-pinene (23.39%), ß-caryophyllene (16.43%), α-pinene (7.55%), sylvestrene (6.61%) and ç-cadinene (4.19%). It was found that the essential oil of A. maximum fruits possessed contact and fumigant toxicities against T. castaneum adults (LD50 = 29.57 µg/adult and LC(50) = 23.09 mg/L air, respectively) and showed contact toxicity against L. bostrychophila (LD(50) = 67.46 µg/cm(2)). Repellency of the crude oil was also evaluated. After 2 h treatment, the essential oil possessed 100% repellency at 78.63 nL/cm(2) against T. castaneum and 84% repellency at 63.17 nL/cm(2) against L. bostrychophila. The results indicated that the essential oil of A. maximum fruits had the potential to be developed as a natural insecticide and repellent for control of T. castaneum and L. bostrychophila.

[Alkaloid constituents of Corydalis adunca].

OBJECTIVE: To study the alkaloid component of Corydalis adunca Maxim. METHODS: The constituents were isolated by chromatographic methods, their structures were elucidated by spectroscopic evidences. RESULTS: Three compounds were purified and their structures were identified, they were identified as dorydaline (I), dehydrocorydaline (II), dihydrosanguinarine (III). CONCLUSION: Compounds I , II are isolated from this plant for the first time.