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At least 1,099 records · Page 61Linked to original sources
PubMed2003

[Analysis on the volatile flavor compounds in Agaricus blazei by GC-MS].

The volatile flavor compounds in Agaricus blazei fruit bodies and mycelia were analyzed by head space analysis GC-MS. 7 kinds of volatile flavor compounds were identified in fruit bodies, and 16 in mycelia. Benzaldehyde and benzyl alcohol are main compounds in fruit bodies, their contents are 43.20% and 28.98% respectively. Benzaldehyde is the main compound in the mycelia and its content is 38.50%. Benzaldehyde and benzyl alcohol are main volatile flavor compounds in Agaricus blazei.

Agaricus↗
PubMed2003

[Study on selective isolation of volatile oil in the seed of Fructus foeniculi].

OBJECTIVE: To study the selective isolation of a single chemical component from volatile oil of Fructus foeniculi by inclucion method. METHOD: The host molecule was selected and a single chemical component isolated from volatile oil by the host-guest recognition. RESULT: X-ray single crystal analysis showed that 1,1,6,6-tetraphenylhexa-2, 4-diyne-1, 6-diol could successfully include 4-[1-propenyl] benzaldehyde from volatile oil of Fructus foeniculi. CONCLUSION: The host-guest inclusion technology can be used to isolate a single component selectively from mixture.

Crystallization↗
PubMed2004

Electroantennogram responses of Chrysoperla carnea (Stephens) to volatiles.

Electrophysiological responses of adult males and females of C. carnea to commonly occurring plant volatiles were recorded using the electroantennogram technique. Responses to 28 volatiles evaluated indicate that both depolarization and recovery to the baseline were rapid in females compared to males. Normalized EAG responses relative to the standard, trans-caryophyllene reveal significant differences between the chemicals as also between the sexes. The response of males to several of the compounds, particularly the terpenoids was higher than females. The pooled averages to the different classes of chemical compounds reveal greater response for fatty acid derivatives and terpenoids, particularly the oxygenated monoterpenes and the sesquiterpenes. These findings are discussed in relation to volatiles released in the cotton ecosystem.

Animals↗
PubMedDate not supplied

[Postradiation volatile secretion of mice attractive for intact individuals].

In early period after exposure to a sub-lethal dose (4 Gy) the exposed mice secreted volatile components (in their urine), which were attractive for intact individuals independently of genotype. The postradiation components were more attractive for allogene individuals than for singene ones. This reaction was different in exposed intact mice, which showed singene attractiveness of volatile secretion. Attractiveness of postradiation volatile components differed from the attractiveness of ones secreted after stress.

Animals↗
PubMed2004

[Investigation on the influential factors of the volatile oil and main constituent content in Pogostemon cablin].

OBJECTIVE: To provide scientific basis for quality evaluation by investigating the influential factors of the volatile oil and main constituent content in Pogostemon cablin. METHOD: Several experiments were carried out to test different habitats, collection periods, processing methods, the level of spreading manure and using agricultural chemical with the volatile oil assay of pharmacopoeia and GC-MS method. RESULT: The effect of different habitats, collection periods, processing methods on volatile oil and main constituent content was shown significantly. CONCLUSION: Such factors as different habitats, collection periods, processing methods should be taken into account when the quality standard of medicinal materials was made.

Ecosystem↗
PubMed2004

Speciation of volatile selenium species in plants using gas chromatography/inductively coupled plasma mass spectrometry.

Gas chromatography/inductively coupled plasma mass spectrometry (GC/ICP-MS) coupled with solid phase micro-extraction can provide a simple, extremely selective and sensitive technique for the analysis of volatile sulfur and selenium compounds in the headspace of growing plants. In this work, the technique was used to evaluate the volatilization of selenium in wild-type and genetically-modified Brassica juncea seedlings. By converting toxic inorganic selenium in the soil to less toxic, volatile organic selenium, B. juncea might be useful in bioremediation of selenium contaminated soil.

Brassica↗
PubMed2004

[Studies on the chemical constituents of the volatiles of Clerodendron bungei].

OBJECTIVE: To analyse chemical constituents of the volatiles of Clerodendron bungei. METHOD: The volatiles of C. bungei were extracted through steam distillation, and then the constituents were separated by GC and identified by MS. RESULT AND CONCLUSION: 33 Compounds were identified. The principal chemical constituents of the volatiles of C. bungei are ethanol, acetone, 1-penten-3-ol,2-pentanol, (Z)-2-penten-1-ol, 3-furaldehyde, 3-hexen-1-ol, 4-hexen-1-ol, 1-hexanol, 1-octen-3-ol, 3-octanol, benzenemethanol, linal-ool oxide, trans-Linalool oxide, linalool,2,5-dimethylcyclohexanol, phenylethyl alcohol, etc.

Acetone↗
PubMed2005

[Analysis of volatile fatty acids in gingival crevicular fluid of patients with chronic periodontitis].

OBJECTIVE: To investigate the volatile fatty acids in gingival crevicular fluid (GCF) and to analyze the relationship between the levels of the volatile fatty acids and chronic periodontitis. METHODS: GCF samples taken from 37 patients with chronic periodontitis and 16 volunteers with healthy periodontal status were analyzed by capillary electrophoresis. RESULTS: The detection frequencies and concentrations of succinic acid, butyric acid and valeric acid were significantly higher in GCF of chronic periodontitis than in that of healthy group. The detection frequencies of propionic acid had no statistic difference between the two groups, but the concentrations of it was significantly higher in inflammation group. We also found that the concentrations of succinic acid, propionic acid and butyric acid were significantly lower in shallow pockets than that in deep pockets. CONCLUSIONS: The volatile fatty acids, especially succinic acid, propionic acid, butyric acid and valeric acid were associated significantly with the severity and inflammation of periodontal disease. The levels of succinic acid, propionic acid and butyric acid in GCF were related to pocket depth.

Adult↗
PubMed2005

[Analysis of volatile components from the flowers of Chrysanthemum morifolium by GC-MS with solid-phase microextraction].

OBJECTIVE: To study a method for extraction and analysis of volatile components from Chrysanthemum morifolium 'gonghuangjv' cv. nov (CM GHJ) and C. morifolium 'gongbaijv' cv. nov (CM GBJ) by solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). METHOD: The volatile components were extracted in different temperature, different balance period and different extraction fiber using head space solid-phase microextraction (HS-SPME), and were identified by CGC-MS. The variety in integral area of each component was observed in different conditions and its relative content was determined by normalization of area. RESULT: The better condition of SPME for C. morifolium was that the sample was extracted using 100 microm polydimethylsiloxane (PDMS) extraction fiber after it had been balanced for 6 hours at 75 degrees C. 53 components from CM GHJ and CM GBJ were identified, and there were 35 same components in CM GHJ and CM GBJ. CONCLUSION: HS-SPME-GC-MS is convenient, rapid and reliable for analysis of volatile components in C. morifolium.

Chrysanthemum↗
PubMed2005

[Classification of terpenes and terpene oxides in volatile oil of Fruit of Acanthopanax senticosus (Rupr. Et Maxim) Harms with gas chromatographic retention parameters].

Gas chromatographic (GC) retention parameters (A and B values) for 24 volatile compounds in volatile oil of Acanthopanax senticosus (Rupr. Et Maxim) Harms were obtained from the retention times under five temperature-programming conditions with self-developed GC_AB software based on Levenberg-Marquardt method. The correlation analysis between A and B parameters of terpene and its oxides was carried out. Good linear relationships between A and B parameters were built for seven monoterpenes (C10H16) , nine sesquiterpenes (C15H24), three monoterpene oxides (C10HnO) and three sesquiterpene oxides (C15HnOx) at the same carbon number, respectively. But poor A-B linearity was built for the group formed from monoterpenes and monoterpene oxides or that formed from sesquiterpenes and sesquiterpene oxides at the same carbon number. At the same time the A-B relationships for monoterpenes, sesquiterpenes and their oxides are not collinear. Therefore, this discipline is applied in the assistant identification for terpenes with different carbon numbers and in the classification between terpenes and their oxides. It shows that GC retention parameters calculated from retention times under several temperature-programming conditions are useful for the classification of monoterpenes, sesquiterpenes and their oxides in the analysis of volatile oils from traditional Chinese herbs.

Chromatography, Gas↗
PubMed2005

[Analysis of volatile oil of garlic by gas chromatography-mass spectrometry].

The volatile oil of garlic was extracted by hydrodistillation method and gas chromatography-mass spectrometry was applied to analyse the compounds in the oil. The best extraction conditions for high-content, effective components were obtained through optimization. The capillary column was an HP-5MS column (25 mm x 0.25 mm i.d. x 0.25 microm); oven temperature increased with a rate of 5 degrees C /min from 80 to 300 degrees C, and then maintained for 20 min; sample size of 1 microL; split ratio of 100:1; carrier gas of helium (1 mL/min). Mass spectra were obtained at 70 eV. The temperatures of injector base, ionization source were maintained at 270 degrees C, 230 degrees C respectively. Under these conditions, twenty compounds in the volatile oil of garlic were isolated and identified, and the content of each was determined. Sulfur-containing compounds were found to be the principal components, of which the major compound was diallyl trisulfide with the content of more than 30%, which is higher than the others in the literature. The experimental results also indicated that hydrodistillation method is an effective method for officinal component extraction. In addition, it was also demonstrated that the garlic volatile oil was stable when stored at 0 degrees C for 6 months.

Garlic↗
PubMed2005

[Analysis of volatile constituents from Anemarrhena asphodeloides by GC-MS].

OBJECTIVE: To study the chemical constituents of the volatile oil from the rhizome of Anemarrhena asphodeloides. METHOD: The volatile oil was steam distillation. Chemical constituents were separated and analyzed by GC-MS. The relative content of each component was determined by area nomalization. RESULT: 24 volatile compounds were isolated and identified for the first time, representing 70.83% of the total oil. CONCLUSION: The main constituents of this oil were aldehydes (31.15%), terpene and their oxide (20.66%), alkyls (8.35%), Furan heterocyclic compounds (6.41%), non terpene alcohol (4.26%). There are 12 compounds with contents over 3%. Among them, borneol has the highest content (9.35%).

Aldehydes↗
PubMed2005

Effect of enzymatic pretreatment on solubilization and volatile fatty acid production in fermentation of food waste.

Food waste can be a valuable carbon source in biological nutrient removal (BNR) systems because of the high C/N and C/P ratio. However, pretreatment is necessary to promote hydrolysis of food waste because of the high concentration of volatile solids associated with organic matter. The influence of the enzymatic pretreatment on acid fermentation of food waste was investigated in this study. Solubilization of particulate matter in food waste was carried out using commercial enzymes. The acidification efficiency and the volatile fatty acid (VFA) production potential of enzymatically pretreated food waste were examined. The highest volatile suspended solid (VSS) reduction was obtained with an enzyme mixture ratio of 1:2:1 for carbohydrase: protease: lipase. An optimum enzyme dosage for solubilization of food waste was 0.1% (V/V) with the enzyme mixture ratio of 1:2:1. In the acid fermentation of enzymatically pretreated food waste, the maximum VFA production and the highest VFA fraction in soluble COD (SCOD) were also achieved at 0.1% (V/N) of total enzyme dosage. Increase in VFA production at this level of enzyme dosage was over 300% compared with the control fermenter. The major form of VFA produced by fermentation was n-butyrate followed by acetate.

Acetates↗
PubMed2006

[Study on the process of inclusion volatile oil of Herba Schizonepetae with beta-cyclodextrin from xiao'er ganmaoshu granule].

OBJECTIVE: To study optimum inclusion process condition for volatile oil with beta-cyclodextrin (beta-CD). METHODS: The optimum preparation condition were investigated by orthogonal design. The influence of utilization beta-CD and oil, inclusion temperature and time were studied to determin the utilization ratio of volatile oil and oil-bearing rate. RESULTS: The optimum preparation conditions were established as: volatile oil: beta-CD was 1:10, the inclusion temperature was 60 degrees C and inclusion time was 3h. CONCLUSION: The method is convenient and can he used for mass production.

Analysis of Variance↗
PubMed2006

[Determination of volatile organic compounds in drinking water by purge and trap gas chromatography/mass spectrometry].

OBJECTIVE: To establish a method for determination of volatile organic compounds in drinking water by purge and trap GC/MS. METHODS: Volatile organic compounds in water were purged and trapped by Tekmar 3100, then desorbed and analyzed by GC/MS. Selective ion masses were used in quantitative measurement. RESULTS: 60 VOCs were separated and analyzed in 36 min. Within concentration range from 0 microg/L to 12 microg/L, the correlation coefficient for 51 target compounds was greater than 0.995. The method detection Limits were in the range from 0.021 microg/L to 0.70 microg/L. Recoveries were between 90% and 120%. RF RSD was less than 30%. CONCLUSION: Purge and trap gas chromatography/ mass spectrometry is a sensitive and accurate method for determination of volatile organic compounds in drinking water.

Gas Chromatography-Mass Spectrometry↗
PubMed1992

Ion-trap detection of volatile organic compounds in alveolar breath.

We describe a method for the collection and microanalysis of the volatile organic compounds in human breath. A transportable apparatus supplies subjects with purified air and samples their alveolar breath; the volatile organic compounds are captured in an adsorptive trap containing activated carbon and molecular sieve. The sample is thermally desorbed from the trap in an automated microprocessor-controlled device, concentrated by two-stage cryofocusing, and assayed by gas chromatography with ion-trap detection. Compounds are identified by reference to a computer-based library of mass spectra with subtraction of the background components present in the inspired air. We used this device to study 10 normal subjects and determined the relative abundance of the volatile organic compounds in their alveolar breath. The breath-collecting apparatus was convenient to operate and was well tolerated by human volunteers.

Air Pollutants↗
PubMed1990

[Effects of processing on volatile oil constituents in nutmeg and on the contents of myristicin].

This paper reports a GC analysis of the volatile oil contained in the nutmeg (Semen Myristicae) prepared by simmering wrapped in flour in hot purified talc, scalding in hot purified talc and stir-frying in smoking wheat bran. The experimental results showed that before and after processing the volatile oil compounds in nutmeg are the same and during processing no known compounds disappeared. The contents of the main volatile oil compounds in nutmeg changed, however, before and after processing, including the amounts of myristicin, one of the toxic compounds in nutmeg. It is suggested that the amounts of myristicin could be decreased notably under certain processing conditions.

Allylbenzene Derivatives↗
PubMed1989

[Volatilization of plant protective agents from plants and soil as potential sources of exposure].

The volatilization of chemical plant-protecting agents from plant and soil surfaces brings about an exposure of men and a contamination of the environment. On the basis of general physicochemical parameters the saturation-concentration, volatilization rate and volatilization half-life-period of selected insecticides is calculated by the help of several equations. Comparable air-concentrations of agents are given for open grounds and for green-houses.

Air Pollutants↗