Composition and Insecticidal Activity of Elsholtzia kachinensis Prain, a Traditional Vegetable and Herbal Medicine.

In recent years, secondary metabolites of plants have attracted researchers' interest as a substitute for synthetic insecticides with many advantages. Elsholtzia kachinensis is an annual herb with medicinal and edible value. In this study, the essential oil (EO) of the aerial part of E. kachinensis was extracted by hydrodistillation, and GC-MS analysed essential oil components. The results show that carvone and dehydroelsholtzia ketone are the main components of the essential oil, accounting for 32.298% and 31.540%, respectively. EO, carvone and dehydroelsholtzia ketone are used to determine the effects against stored-product insects Lasioderma serricorne, Tribolium castaneum, Sitophilus oryzae and Liposcelis bostrychophila. The essential oil showed the most vital contact and fumigation toxicity to L. serricorne, of which LD50 and LC50 values were 3.85 µg/adult and 7.74 mg/L air, respectively. S. oryzae did not show repellent activity, but the repellent rate of the other three species reached 90% under EO treatment at a concentration of 78.63 nL/cm2. Therefore, the essential oil of E. kachinensis has an insecticidal effect and has the potential to be developed as a new eco-friendly insecticide.

Chemical compositions and repellent activity of Clerodendrum bungei Steud. essential oil against three stored product insects.

BACKGROUND: Several species of Verbenaceae have been widely used in medicine, and some species of Verbenaceae have been observed good insecticidal activity, such as Lantana camara and Vitex negundo. There is no report about repellent activity of Clerodendrum bungei Steud. (C. bungei) against stored product insects. The chemical composition of C. bungei essential oil (EO) were identified, repellent activity of methanol extract, EO of C. bungei and two main components of EO against T. castaneum, L. serricorne and L. bostrychophila were evaluated for the first time. RESULTS: EO of C. bungei was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS) and GC. A total of 25 components of the C. bungei EO were identified. The principal compounds in the EO were myristicin (75.0%), 2,2,7,7-Tetramethyltricyclo[6.2.1.0(1,6)]undec-4-en-3-one (4.1%) and linalool (3.4%). Results of bioassays indicated that C. bungei EO exerted strong repellent activity against three target insects. As main constituents, myristicin and linalool also had certain repellency. CONCLUSION: This work suggests that the EO of C. bungei has promising potential to develop into botanical repellents for the control of pest damage in warehouses and grain stores.

Impact of calcium peroxide dosage on the control of nutrients release from sediment in the anoxic landscape water.

The anoxic and reductive aquatic environment is formed easily in summer due to the global warming, which may accelerate endogenous release. In this experiment, four different dosages of calcium peroxide (CaO2) were adopted to study the control effects of nutrients release from the sediments in the simulated landscape waters. The results demonstrated that CaO2 addition could effectively improve the physicochemical properties and microbial composition in sediments, and an obvious improvement was achieved with a larger dosage. It was observed that the surface sediments of experiment groups were oxidized to form a capping barrier between the sediment and overlying water, which might cut off the pollutant diffusion in sediment. Meanwhile, CaO2 could decrease the nutrients concentration in water obviously, and the reduced effect was positively correlated with the CaO2 dosage. Compared with the nutrients release fluxes in CK (105.89 mg-TN m-2 day-1, 106.48 mg-NH4+-N m-2 day-1, 4.14 mg-TP m-2 day-1, and 4.30 mg-SRP m-2 day-1), the CaO2 dosages of 0.12 and 0.18 kg m-2 could entirely inhibit the nutrients release from sediment, and partially reduce the original pollutants in the overlying water. However, 0.18 kg m-2 CaO2 would cause a higher increase of pH value and NO2--N concentration, and bring potential risk to the aquatic ecosystem. Therefore, 0.12 kg-CaO2 m-2-sediment was selected as the optimal dosage by considering the control effect, economic cost, and potential risk comprehensively. In general, this study provided a quantitative usage method of CaO2, which is convenient and effective to prevent or control the nutrients release from sediment caused by anoxic and reductive condition in summer.

Release characteristics of nitrogen and phosphorus from sediments formed under different supplemental water sources in Xi'an moat, China.

The endogenous release of nutrients from sediments contributes to the eutrophication of landscape water to a certain degree, which depends on the characteristics of sediments. The study explored the characteristics of nitrogen (N) and phosphorus (P) released from two different sediments, which were deposited from reclaimed water (SRW) or surface water (SSW) respectively in Xi'an moat. This paper aimed to compare the effects of nutrient release from SRW and SSW on the water quality. Results showed that the maximum increase rates reached 1.21 mg TN/(L·day) and 0.11 mg TP/(L·day), respectively, in the overlying water of SRW, which were 1.6 and 2.8 times those of SSW. The released amounts of SRW were 0.192 mg TN/g and 0.038 mg TP/g, which were 4.1 and 12.7 times those of SSW. Meanwhile, the densities of benthic algae in SRW and SSW were 5.605 × 109 and 2.846 × 108 cells/L, respectively. Moreover, the species number and individual sizes of benthic algae in SRW were also larger than those in SSW, which played an important role in the nitrogen circulation. Unexpectedly, oxidation reduction potential (ORP) level of SRW was lower than that of SSW, although SRW has a higher dissolved oxygen level. Therefore, the N and P concentrations in the overlying water of SRW were considerably higher than those of SSW, which was mainly attributed to the higher nutrient contents and lower ORP in SRW.

Lung autotransplantation technique in the treatment for central lung cancer of upper lobe.

AIM: To assess the feasibility and benefit of lung autotransplantation technique in surgical treatment for central lung cancer of upper lobe which could not tolerate pneumonectomy. METHODS: From August 2000 to August 2006 seven patients, who were proved to be malignant pathologically through fiber-bronchoscope before operation and could not tolerate pneumonectomy, underwent lung autotransplantations. Double-sleeve resection of the right upper and middle bilobectomy (or left upper lobectomy) and involved pulmonary artery was performed firstly. Because the length of resected bronchus or pulmonary artery involved by tumor was too long to perform tension-free anastomosis, we transplanted the inferior pulmonary vein to the proximal stump of the superior pulmonary vein. The bronchus and pulmonary artery were anastomosed in turn. Then radical hilar and mediastinal lymphadenectomy was performed. RESULTS: Until August 2006, among the seven patients who underwent lung autotransplantations, five patients had been free of tumor recurrence for 2 to 73 months with good quality of life. Radioisotope scanning of the replanted lobe of one patient revealed normal perfusion 6 years postoperatively. One patient received resection of the replanted lobe because of pulmonary vein thrombus on the second day after transplantation, and died of respiratory failure caused by pulmonary relapse on 15th month postoperatively. Another patient died of brain metastases 31 months postoperatively. No anastomotic stoma fistula occurred in these seven patients. CONCLUSION: Lung autotransplantation is an alternative technique for pulmonary preservation for patients with centrally placed tumor of the upper lobe, whose pulmonary function is too poor to undergo pneumonectomy.