Efficacy of Compounds Isolated from the Essential Oil of Artemisia lavandulaefolia in Control of the Cigarette Beetle, Lasioderma serricorne.

To develop natural product resources to control cigarette beetles (Lasioderma serricorne), the essential oil from Artemisia lavandulaefolia (Compositae) was investigated. Oil was extracted by hydrodistillation of the above-ground portion of A. lavandulaefolia and analyzed using gas chromatography-mass spectrometer (GC-MS). Extracted essential oil and three compounds isolated from the oil were then evaluated in laboratory assays to determine the fumigant, contact, and repellent efficacy against the stored-products' pest, L. serricorne. The bioactive constituents from the oil extracts were identified as chamazulene (40.4%), 1,8-cineole (16.0%), and ß-caryophyllene (11.5%). In the insecticidal activity assay, the adults of L. serricorne were susceptible to fumigant action of the essential oil and 1,8-cineole, with LC50 values of 31.81 and 5.18 mg/L air. The essential oil, 1,8-cineole, chamazulene, and ß-caryophyllene exhibited contact toxicity with LD50 values of 13.51, 15.58, 15.18 and 35.52 µg/adult, respectively. During the repellency test, the essential oil and chamazulene had repellency approximating the positive control. The results indicated that chamazulene was abundant in A. lavandulaefolia essential oil and was toxic to cigarette beetles.

[Research of herb components on scavenging harmful components and reducing cytotoxicity of cigarette smoke].

OBJECTIVE: To study the in vitro effect of herb components on scavenging harmful components of cigarette smoke such as radicals, polycyclic aromatic hydrocarbons, nitrosamines in vitro, and its reducing effect on cytotoxicity of cigarette smoke. METHOD: spectrophotometry was used to examine the scavenging effect of herb components on DPPH free radicals, superoxide anion radical, and hydroxyl radical, and the results were compared with the anti-oxidation of ascorbic acid. Fluorescence spectroscopy was used to examine the scavenging effect of herb components on polycyclic aromatic hydrocarbons. UV spectrophotometry was used to examine the scavenging effect of herb components on volatile nitrosamines. MTT assay was used to examine cytotoxicity of cigarette smoke. RESULT: All the herb components showed a certain scavenging effect on DPPH free radicals, superoxide anion radical, hydroxyl radical, polycyclic aromatic hydrocarbons and volatile nitrosamines, espacially the ginkgo biloba extract (GBE), flavonoids of glycyrrhiza, procyanidine, total saponins in ophiopogonin, total saponins of astragalus and epimediun flavonoids. After these six herb components were added to cigarette, the cytotoxicity of cigarette smoke on BEP2D cells was remarkably reduced, by increasing cell survival fraction (SF, %) and mean lethal dose (DML). CONCLUSION: The herb components can scavenge harmful components of cigarette smoke such as radicals, polycyclic aromatic hydrocarbons and nitrosamines, which reduce the damage of cigarette smoke on human being.

Repellent activities of essential oils rich in sesquiterpenoids from Saussurea amara (L.) DC. and Sigesbeckia pubescens Makino against two stored-product insects.

The essential oils (EOs) from aerial parts of Saussurea amara (L.) DC. (SAEO) and Sigesbeckia pubescens Makino (SPEO) were analyzed for their chemical composition by GC-MS, and their repellent activities against adults of the red flour beetle, Tribolium castaneum Herbst, as well as the booklouse, Liposcelis bostrychophila Badonnel, were evaluated for the first time. Results of GC-MS analysis indicated that both SAEO and SPEO were characterized by high content of sesquiterpenoids (relative content > 70%) including oxygenated sesquiterpenoids. The two oil samples and their major component caryophyllene oxide exerted beneficial repellent effects on T. castaneum and L. bostrychophila at 2 and 4 h post-exposure. At 4 h post-exposure, the PR value of caryophyllene oxide could still reach 92% (class V) against T. castaneum at minimum testing concentration of 3.15 nL/cm2, and this compound was observed to result in the greatest repellency (PR = 100%) against L. bostrychophila at 12.63 nL/cm2. This work confirmed the potent repellent efficacy of SAEO and SPEO for controlling pest damage and suggested their potential to be developed into botanical repellents.