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[Effects of volatiles from different trophic level on foraging behavior of Aphidius avenae].

The responses of female Aphidius avenae to volatiles from undamaged wheat plant, Sitobion avenae and Rhopalosiphum padi, aphids-plant complexes and aphids damaged plant were investigated in wind tunnel and Y-tube olfactometer. The volatiles from undamaged wheat plant, S. avenae and R. padi were much less attractive to A. avenae than those from aphids-plant complexes and aphids-damaged plant. Although the parasitic rate was much lower, the R. padi-plant complexes and R. padi damaged plant were also attractive to A. avenae. Identification of volatiles by GC-MS showed that the main volatiles induced by aphids feeding were 2-camphene, 6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol, Z-3-hexenyl-acetate, and methyl salicylate, among which, 6-methyl-5-hepten-2-one and 6-methyl-5-hepten-2-ol were more attractive to A. avenae, while methyl salicylate was not attractive.

Animals↗

[Determination of chemical constituents of the volatile oil from Curcuma longa by gas chromatography-mass spectrometry].

The study of chemical constituents of the volatile oil from Curcuma longa is reported. The volatile oil was extracted by steam distillation. Fifteen components in the oil were separated and identified by gas chromatography-mass spectrometry(GC/MS). The results were elucidated based on the NBS standard mass spectral data. The total ion current chromatogram showed their mass fraction by normalization method. alpha-curcumene, alpha-zingiberene, 1,8-cineole and zerumbone, which had been reported before were found in Curcuma longa volatile oil, but 1-(3-cyclopentylpropyl)-2,4-dimethylbenzene, beta-sesquiphellandrene, germacrene etc identified simultaneously in the oil had never been reported. The major chemical constituent of the volatile oil from Curcuma longa is alpha-curcumene.

Curcuma↗

[Selective isolation of anethole from volatile oil of Foeniculum vulgare Mill by inclusion crystalline with chela-shape host].

AIM: To isolate the components from the volatile oil of Foeniculum vulgare Mill. METHODS: According to the function of molecular recognition of supramolecular chemistry, chela shape molecule, trans-1, 2-biphenyl-1, 2-acenaphthendiol was used as host molecule and the volatile oil of Foeniculum vulgare Mill as guest molecule. Trans-1, 2-biphenyl-1, 2-acenaphthendiol can recognize the components that endowed with interactional complementarity and form inclusion compound as crystals. RESULTS: The anethole in the volatile oil was selectively included as trans-1,2-biphenyl-1,2-acenaphthendiol which was obtained in pure state from the inclusion compound by Kugelrohr vacuum technology. The formation of inclusion compound was confirmed by means of IR and powder XRD. The structure of the selectively isolated component was elucidated as trans-anethole by means of IR, 1HMMR and MS. CONCLUSION: The experimental results showed that the method is simple, rapid and selective for isolation anethole from volatile oil of Foeniculum vulgare Mill.

Allylbenzene Derivatives↗

Intake of volatile N-nitrosamines and their ability to exogenously synthesize in the diet of inhabitants from high-risk area of esophageal cancer in southern China.

OBJECTIVE: Nan'ao County in Guandong Province is a high-risk area of esophageal cancer in Southern China. Of the suspected etiological factors in the environment, N-nitrosamines and their precursors have received the greatest attention. METHODS: Sixty samples of the diet ingested by the inhabitants were collected and detected for volatile N-nitrosamines and their precursors. Five N-nitrosamines detected by Gas Chromatography-Thermal Energy Analyzer were N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosopyrrolidine, N-nitrosopiperidine and N-nitrosomethyl-benzylamine. RESULTS: The average content of 5 volatile N-nitrosamines in the diet was 312.0 micrograms/kg (median). The daily intake of the nitrosamines was 286.5 micrograms/head/day. Only the ability to exogenously synthesize N-nitrosopiperidine was powerful among 5 volatile N-nitrosamines. By a computerized stepwise regression analysis and curve fitting, we studied the correlation among the nitrosamines, the precursors and the major food items in the samples. CONCLUSION: It demonstrated that a relatively high content of volatile N-nitrosamines was present in the diet collected in the area.

Adult↗

[Chemical constituents in volatile oil from the flos of Dendranthema indicum var. aromaticum var. nov].

OBJECTIVE: To analyse chemical constituents of volatile oil from Dendranthema indicum var. aromaticum var. nov. by GC-MS. METHOD: The volatile oil was extracted from Dendranthema indicum var. aromaticum var. nov. through steam distillation and was analysed with different kinds of capillary columns to find out the optimal conditions. The content of compositions of volatile oil was determined with normalization method, and the constituents were identified by GC-MS. RESULT: 44 Components were separated and identified, which accounted for over 43% of total volatile oil. CONCLUSION: The main constituents in the essential oils from Dendranthema indicum var. aromaticum var. nov. are Verberol, (-)zingiberene, beta-sesquiphellandrene, farnesene, transchrysanthenyl acetate, and caryophyllene.

Asteraceae↗

[Kinetic study on the volatility of menthol and borneol].

OBJECTIVE: To study the volatile regularity of menthol and borneol in granule and lozenge at different temperature. METHOD: Kinetic method with GC being detection technique. RESULT: The volatility of menthol and borneol acts as a pseudo first-order reaction in open system. Under the same condition, the volatile rate of menthol and borneol in granule is four times as fast as that in lozenge, and the volatile rate of borneol is faster than that of menthol. CONCLUSION: This study can be applied to improve the quality of lozenges containing menthol or/and borneol.

Camphanes↗

[Advances of studies on the effects of plant volatiles on insect behavior].

Plant volatiles show different effects on insect behaviors, which included luring, repelling and killing. After damaged by phytophagous insects, some host plants could send volatiles luring natural enemies as an indirect defense. A summarize on the new advances of plant volatiles was given. The role of plant volatiles in integrated pest management in future was also discussed.

Animals↗

[Chemical composition of volatile oil from Chromolaena odorata and its effect on plant, fungi and insect growth].

The volatile oil from C. odorata had a significant effect on the growth of plants, fungi and insects. The result showed that the seedling growth of five test plants was obviously inhibited, in the order of ryegrass > Chinese cabbage > radish > snap been > rice. The inhibitory effect of the oil at its middle concentration (800 mg.L-1) for Pyricularia grisea was the strongest, the next was to Phytophthora nicotianae, and the weakest was to Fusarium axysporum. The inhibitory percentage was 61.40%, 29.27% and 14.44%, respectively. The volatile oil from C. odorata at the dose of 10-20 microliters.plant-1 had a significant oviposition deterrent effect on Phyllotreta striolata and Plutella xylostella. The volatile oil from C. odorata was analyzed by GC/MS and thirty components were identified. Terpenoids compounds were major components of the volatile oil, such as trans-caryophyllene (16.58%), delta-cadinene (15.85%), alpha-copaene (11.58%), caryophyllene oxide (9.63%), germacrene-D (4.96%), and delta-humulene (4.32%).

Animals↗

Effect of chemical and microbial amendments on ammonia volatilization from composting poultry litter.

Research has shown that aluminum sulfate (alum) and phosphoric acid greatly reduce ammonia (NH3) volatilization from poultry litter; however, no studies have yet reported the effects of these amendments on field-scale composting of poultry litter. The objectives of this study were to (i) evaluate NH3 volatilization from composting litter by measuring both NH3 volatilization and changes in total nitrogen (N) in the litter and (ii) evaluate potential methods of reducing NH3 losses from composting poultry litter. Poultry litter was composted for 68 d the first year and 92 d the second year. Eleven treatments were screened in Year 1, which included an unamended control, a microbial mixture, a microbial mixture with 5% alum incorporated into the litter, 5 and 10% alum rates either surface-applied or incorporated, and 1 and 2% phosphoric acid rates either surface-applied or incorporated. Treatments in Year 2 included an unamended control, a microbial mixture, alum (7% by fresh wt.), and phosphoric acid (1.5% by fresh wt.). Alum and phosphoric acid reduced NH3 volatilization from composting poultry litter by as much as 76 and 54%, respectively. The highest NH3 emission rates were from microbial treatments each year. Compost treated with chemical amendments retained more initial N than all other treatments. Due to the cost and N loss associated with composting poultry litter, composting is not economical from an agronomic perspective compared with the use of fresh poultry litter.

Air Pollutants↗

[Bioactivity of volatile oils from Myoporum bontioides on Plutella xylostella].

This study showed that the volatile oils from Myoporum bontioides had a significant repellent action on Plutella xylostella. When Plutella xylostella adults entered into the 4-arm selective olfactometer, the preferred times and average staying duration, in the order from more to less, were 3, 1, 4, and 2 arms, which showed a tendency of keeping away from the treatment arms. The males were more sensitive to the volatile oils than the females, when the velocity of flow was 200 ml.min-1. On the first day of the 3rd bioassay, the oviposition deterrent rate and IIPC of the volatile oils on Plutella xylostella adults was 94.48% and 0.0552, respectively. A liquid component of the volatile oils from Myoporum bontioides was isolated, purified, and identified as myoporone.

Animals↗

[Chemical components of Vetiveria zizanioides volatiles].

The chemical components of the volatiles from Vetiveria zizanioides were analyzed by SPME and GC-MS. In the roots, the main component was valencene (30.36%), while in the shoots and leaves, they were 9-octadecenamide (33.50%), 2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene (27.46%), and 1,2-benzendicarboxylic acid, diisooctyl ester(18.29%). The results showed that there were many terpenoids in the volatils. In shoot volatiles, there existed 3 monoterpenes, 2 sequiterpenes and 1 triterpene. Most of the volatiles in roots were sesquiterpenes.

Gas Chromatography-Mass Spectrometry↗

[Repellent effect of volatile oil from whitefly (Syngonium podophyllum) on aphids and its chemical constituents].

The interference effect of volatile oil from whitefly (Syngonium podophyllum) on aptera aphid, guard aphid (Aphis gossypii), mustard aphid (Lipaphis erysimi) and red peach aphid (Myzus persicae) was studied by using four arms olfraetometes. The results showed that the volatile oil had distinct repelling effect. The staying periods of test aphids in test areas were obviously shorter than in control areas, and the selecting frequencies were less than the control, too. The volatile oil did not show repelling effect on red peach aphid at the test concentrations. The components of the volatile oil from S. podophyllum were analysed by GC-MS. 43 constituents were identified.

Animals↗

[Communicative multiplication of secondary disorders in blood formula and immunity in groups of intact mice caused by volatile compounds excreted by irradiated animals].

It was shown that immunosupressive substances excreted by the irradiated mice are highly volatile. Even the excretion from one irradiated mouse could induce disorders in the immune system and blood formula of intact recipients exposed to the volatile substances. In turn, a dominate mouse from a group of the exposed recipients could cause the disorders in the next intact group. Samples of urine from irradiated or exposed to the volatile substances could cause the same effect. The experiments showed a mechanism of secondary post-radiation disorders in animal groups through volatile chemical signals.

Animals↗

Volatilization of heavy metals during incineration of municipal solid wastes.

Incineration experiments with MSW, which had been impregnated with heavy metals, were presented to obtain information on the volatilization behavior of the elements cadmium(Cd), lead (Pb), and zinc (Zn) under different conditions. Experiments were carried out in a bubbling fluid bed system connected to a customized inductively coupled plasma optical emission spectroscopy (ICP-OES) for analyzing metals in the flue gas. The results indicated that the combustion temperature, the gas atmosphere, and the chlorine content in the flue gas could affect the volatilization behavior of heavy metals. In the fluidized bed combustion, a large surface area was provided by the bed sand particles, and they may act as absorbents for the gaseous ash-forming compound. Comparer with the metals Cd and Pb, the vaporization of Zn was low. The formation of stable compounds such as ZnO x Al2O3 could greatly decrease the metals volatilization. The presence of chlorine would enhance the volatilization of heavy metals by increasing the formation of metal chlorides. However, when the oxygen content was high, the chlorinating reaction was kinetically hindered, which heavy metals release would be delayed.

Air Pollutants↗

[Determination of constant for the inclusion complex of Yinqiao volatile oil with beta-cyclodextrin].

OBJECTIVE: To determine the constant for the inclusion complex of Yinqiao volatile oil with beta-cyclodextrin. METHOD: The stability constant for the inclusion complex of Yinqiao the volatile oil with beta-cyclodextrin was detemined under multiwavelength by ultraviolet spectroscopy, and spectroscopy feature for inclusion complex was studied. The phase solubility-curve showed the inclusion proportion. The inclusion complex of Yinqiao the volatile oil with beta-cyclodextrin was prepared by saturated aqueous solution. The DTA spectroscopy of inclusion complex was different from not only oil with beta-cyclodextrin but also the mixture of them. RESULT: The inclusion complex of Yinqiao the volatile oil with beta-cyclodextrin was formed. The experimental data of inclusion complex fitted well to the molar ratio of 1:1. There was good liner feature under multiwavelength of ultraviolet spectroscopy. CONCLUSION: Adopting multiwavelength method may determine the appearant stability constant of multicomponential traditional drug. The determination of the stability constant of the inclusion complex can be used in traditional drug.

Calorimetry, Differential Scanning↗

Changes in aroma volatile compounds and ethylene production during "Hujingmilu" peach (Prunus persica L.) fruit development.

Changes in ethylene production rate, respiration rate, and aroma volatile composition was determined from the immature to mature stage in "Hujingmilu" peach (Prunus presica) fruit. Flesh firmness, fruit size, ground color of skin, and total soluble solids (TSS), titratable acidity (TA) in juice were analyzed, and ACC, ACC synthase and ACC oxidase activities were measured. With the increase of fruit maturity, fruit size, L* value, and TSS and major reducing sugar contents increased, whereas fruit firmness, skin hue angle (h degrees ), and juice TA and organic acid contents decreased. In immature fruits, a C(6)-aldehydes (trans-2-hexenal) and C(6)-alcohols (cis-3-hexenol) were the major components, corresponding to the low ethylene production and high respiration rates. With increasing of fruit maturity, the C(6)-C(12) lactonic compounds, particularly gamma- and delta-lactones became the dominant volatile constituents, which increased significantly at the climacteric stage. These facts suggest that ethylene production may be involved in the regulation of lactones production in maturing peach fruit. The activity of ACC synthase in the mesocarp declined during the climacteric rise of ethylene. ACC level and ACC oxidase activity in mesocarp were consistent with the onset of ethylene production in fruit. Major aroma volatiles are thought to form in conjunction with the initiation of climacteric rises in respiration and ethylene production. Detection of changes in aroma volatile compound synthesis rate in peach may be useful as index of maturity reflecting the current physiological stage of peach fruit development.

Amino Acid Oxidoreductases↗

[Studies on the preparation technology of beta-cyclodextrin inclusion compound for chuanxiong volatile oil extracted with CO2 supercritical fluid].

OBJECTIVE: To explore the preparation technology of beta-cyclodextrin inclusion compound for chuanxiong volatile oil. METHOD: Orthogonal test was used to evaluate the influence of the 4 factors, including the proportion of volatile oil to beta-cyclodextrin, the mode of mixing, inclusion temperature and mixing time. RESULT: The best inclusion condition is the proportion of volatile oil to beta-cyclodextrin 1:9, the mode of mixing grinding, inclusion temperature 60 degrees C and inclusion time 90 min. CONCLUSION: The best inclusion technology of chuanxiong volatile oil is confirmed.

Carbon Dioxide↗

[Establishment of high-yield suspension cell line of Curcuma zedoaria (Berg.) Rosc and study on the volatile oil synthesis-controlling with precursors].

The condition for high-yield suspension cell line and the precursors of volatile oil synthesis of Curcuma zedoaria (Berg.) Rosc were studied. The results showed that the light yellow particle callus was suitable for establishment of the high-yield suspension cell line. The optimum conditions for cell growth were MS medium added 15-30 g/L glucose and 15-30 g/L sucrose (1:1) as carbon source, the total concentration of 80 mmol/L nitrogen source combined NH4+ with NO3- (1:3), hormones of 3.0-5.0 mg/L 6-BA, 1.0 mg/L 2,4-D and dark culture after 10-15 days light culture. The 229 g/L cell (FW) and 2.11% content of volatile oil were obtained in vitro. The addition of precursors of calcium pantothenate, ammonium acetate and potassium acetate during the middle period of the cell suspension culture enhanced the volatile oil content respectively, and ammonium acetate was most effective among them. The highest yield of volatile oil obtained was 3.11% and 8.27 g/L respectively , which was 1.25 and 1.2 times of the control group.

Acetates↗