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61.
We evaluated the protection afforded by an oil formulation against non-compatible fungicides in mixtures with conidia of the entomopathogenic fungi Metarhizium anisopliae (Ma) and Beauveria bassiana (Bb). Under laboratory conditions, viability of unformulated (aqueous suspensions) Ma conidia was harmed by recommended label doses of carbendazim (not tested for Bb), and both Ma and Bb conidia were affected by triadimefon. On the other hand, effect of fungicides was usually nil or minimal on conidia formulated as oil-containing suspensions (emulsifiable oil + water). Germination rates for unformulated and oil-formulated Ma conidia subjected to carbendazim were reduced by 77.3 and 12.1%, respectively, compared to their fungicide-free counterparts. Germination rates at 16 h post-inoculation for unformulated and oil-formulated Bb conidia subjected to triadimefon were reduced by 20.5 and 5.5%, respectively, compared to their fungicide-free counterparts. No differences were observed at 20 h post inoculation, indicating a fungistatic action of this compound on Bb conidia. Virulence of unformulated conidia amended with fungicides against third instar Diatraea saccharalis larvae was negatively affected compared to their formulated counterparts. These results suggest that oil-formulated conidia can be effectively protected from damage caused by chemicals, which could have applications in tank mixing or alternate applications with shared spraying equipment, being especially relevant for IPM programs in which mycopesticides and chemicals are simultaneously sprayed.  相似文献   
62.
Microbial lipids produced by oleaginous microorganisms, also called microbial oils and single cell oils (SCOs), are very promising sources for several oil industries. The exploration of efficient oleaginous yeast strains, meant to produce both high-quantity and high-quality lipids for the production of biodiesel, oleochemicals, and the other high value lipid products, have gained much attention. At present, the number of oleaginous yeast species that have been discovered is 8.2% of the total number of known yeast species, most of which have been isolated from their natural habitats. To explore high lipid producing yeasts, different methods, including high-throughput screening methods using colorimetric or fluorometric measures, have been developed. Understanding of the fatty acid composition profiles of lipids produced by oleaginous yeasts would help to define target lipid-related products. For lipid production, the employment of low-cost substrates suitable for yeast growth and lipid accumulation, and efficient cultivation processes are key factors for successfully increasing the amount of the accumulated lipid yield while decreasing the cost of production.  相似文献   
63.
Relationships between soil chemistry and population chemotype structure of Thymus pulegioides have been studied. The analysis of correlations suggest that an increased carbonate content in soil decreases the chemotype diversity of a population (as calculated by use of the Shannon index): the proportion of linalool chemotype plants rises and that of the phenol chemotype plants declines. In addition, the chemotype diversity decreases with increasing frequency of linalool chemotype, and increases with increase of carvacrol chemotype.  相似文献   
64.
The biodegradation of olive oil mill wastewater (OOMW) by Coriolus versicolor and Funalia trogii was investigated. Initial COD concentration, agitation and inoculum size were all found to be significant for biodegradation. Adding glucose, sulphate or nitrogen had no effect on biodegradation. During growth in optimum conditions, C.versicolor removed approximately 63% COD, 90% phenol and 65% colour within 6 days and F. trogii removed approximately 70% COD, 93% phenol and 81% colour of the OOMW used. The fungi also excreted large amounts of extracellular laccase into the medium. High biodegradation yields were also obtained by fungi immobilized in calcium alginate gels.  相似文献   
65.
Pollution from the oil shale dump in Maoming, Guangdong Province, China, was a major social problem due to the great amount of environmental damage it caused. Therefore, a great deal of attention needed to be paid for the ecological restoration and reconstruction. The objective of this study was to investigate the species composition of soil fauna and its diversity in oil shale dumps after the application of different ecological restoration schemes in order to understand the impact they had on ecological restoration. Three plots were selected on an oil shale dump near the city of Maoming. The “north plot” was a newly-planted young forest mixed with various tree species, while the “south plot” was a 20-year-old Acacia auriculaeformis forest, and the “control plot” was a 20-year-old naturally-recovering grassland. Soil animals, mainly including macro-meso groups, were collected by hand-sorting and Tullgren funnel extraction. They were then identified to family or genus level with only a small portion to order (e.g. Chllopoda) or species (e.g. Isopoda) level. The specimens obtained in the present study was 11164 individuals, belonging to 27 orders and 110 families or genera. The Shannon index (H′), DGs (based on species) and DGg (based on groups) were used to analyze the diversity of soil animals between different plots. The major results were as follows: A total of 33 families or genera belonging to nine orders were found in the “north plot”. The main group was Caritermes, accounting for 63.4% of the total, followed by Tetramorium with 21.3%. Hymenoptera, mainly Formicidae, had more genera than others, accounting for 80% of the total genera in this group. The diversity of soil animals in this plot was very low because the H′ index was only 1.2, while the DGs index was 4.0 and the DGg index was 1.3. A total of 61 families or genera belonging to 23 orders were found in the “south plot”. Malmcoangelia and Tetramorium were the main groups, which accounted for 60.3% and 10.2%, respectively. Two genera of Annelda and two genera of Isopoda only accounted for 2.6% and 1.9%, respectively, but they were considered to be major groups due to their large body sizes and the distinct characteristics of their habitat. Acarina had a greater number of individuals and families or genera with its individual number accounting for 67.5% of the total, and the number of families or genera of this group account for 70% in this plot. The diversity indexes (H′, DGs and DGg) in this plot were significantly higher than those in the “north plot”, and were 1.65, 16.7 and 7.75, respectively. In the “control plot”, there were 67 families or genera of soil animals belonging to 23 orders. The main groups were Tetramorium (20%), Lasius (17.1%), Bothriomymex of Formicidae (13.8%), and Malmcoangelia of oribatid mites (14.5%). Formicidae of Hymenoptera was the group with the maximum number of individuals, accounting for 51.0%, while Diplopoda had the most families or genera. The H′ and DGs indexes, being 2.54 and 17.7, were higher than those in the “south plot”, while the DGg index of 7.20 was lower than that in the “south plot”. The results showed that the species composition and diversity indexes were higher in the “south plot” than in the “north plot” and the “control plot”, which demonstrated that using Acacia auriculaeformis forest to restore the oil shale dump was an effective approach in terms of soil biodiversity.  相似文献   
66.
Apium nodiflorum (L.) Lag. (water celery) is an hydrophytic plant forming dense submerged populations occurring along streams and rivers of Europe. In the present work we provided new insights into the phytochemistry and biology of A. nodiflorum. In particular, we studied the chemical profile of essential oil and polar extracts obtained from the flowering aerial parts of water celery growing in central Italy, together with the essential oil biological activities, namely antimicrobial, antioxidant and cytotoxicity on tumour cells. In addition, we correlated the productivity in secondary metabolites to the secreting structures through a detailed micromorphological study. The essential oil was dominated by two main chemotypes, characterized by myristicin and limonene, respectively. The oils showed significant toxicity on tumour cells, as evidenced by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, with IC50 values in the range 3.8–15.9 μg mL?1, together with inhibitory effects on Candida albicans (inhibition zones of 10–11 mm). HPLC-MS analysis showed the caffeoylquinic acids and quercetin-3-O-glucoside as the most abundant phenolic compounds. Ducts and vittae were the principal secretory structures of vegetative (leaves and stems) and reproductive (fruits) parts, respectively, storing mainly essential oil. Results of this work provide scientific evidences for the possible valorization and exploitation of water celery.  相似文献   
67.
68.
A novel synthetic method of 3-substituted furans was developed and syntheses of perillen and dendrolasin are described.  相似文献   
69.
Abstract

The effects of no. 20 diesel oil exposure, 2,4-dichlorophenol (2,4-DCP) exposure and combined exposure on the antioxidant defences of Daphnia magna have been studied systematically for the first time. Daphnia magna was exposed for 1 day or 10 days to several concentrations of 0, 0.005, 0.01, 0.05, 0.1, 0.5 or 1.0 mg L?1 solutions. Antioxidant defences consisting of the levels of reduced glutathione (GSH) and glutathione disulfide (GSSG) and activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), selenium dependent glutathione peroxidase (Se-GPx) and glutathione S-transferase (GST) of daphnids were determined to evaluate their protective roles and to analyse the occurrence of oxidative stress. The possible antioxidant defence mechanisms are discussed. Furthermore, GST can be a potential biomarker and an early-warning index for the pollutants in waters in that GST responded sensitively to 1 day and 10 days of exposure to diesel oil and 2,4-DCP and 10 days of combined exposure. Crossover comparisons showed an antagonistic action about the no-observed-effect concentration (NOEC) against Daphnia magna, which needs further studies.  相似文献   
70.
In this study, the amounts of trace elements (Fe (II) and Cu (II)) and pigments (chlorophyll and carotenoid) in soybean oil were evaluated under high voltage electric field (HVEF) bleaching method at different voltage (10 and 20 kV), temperature (35–65 °C), time (0−30 min) and clay percentage (0.5–2 %) and then were compared to the industrial bleaching method (IBM). The kinetic data of ions and pigments adsorbed on activated bentonite clay under IBM and HVEF at two voltages of 10 and 20 kV followed the mechanism of the pseudo-first-order model (PFOM). The carotenoid and chlorophyll equilibrium data followed a Freundlich isotherm type model, which demonstrated multilayer adsorption under HVEF. The thermodynamic parameters (ΔG°, ΔH°, and ΔS°) displayed that the adsorption of trace metal ions and pigments on bentonite clay under IBM and HVEF were feasible, endothermic and spontaneous between 35 and 65 °C. The results indicated that the HVEF, especially at higher voltage, has a high remarkable capability to remove metal ions and pigments from soybean oil than the IBM. The highest removal capacity for metal and pigments of soybean oil bleaching were obtained in the order of HVEF-20 kV > HVEF-10 kV > IBM.  相似文献   
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