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PubMed1996

Evaluation of chemical amendments to reduce ammonia volatilization from poultry litter.

Ammonia volatilization from poultry litter often causes high levels of atmospheric ammonia in poultry houses, which is detrimental to both farm workers and birds. Ammonia emissions from houses also aggravate environmental problems, such as acid rain, and result in a loss of fertilizer nitrogen. The objectives of this study were to determine the effect of litter amendments on ammonia volatilization and to determine the effect of these amendments on nitrogen and phosphorus content in litter. The results of this research indicate that alum [Al2(SO4)3.18H2O], ferrous sulfate (FeSO4.7H2O), and phosphoric acid (H3PO4) dramatically reduce ammonia volatilization form litter. The amount of ammonia lost from litter treated with sodium bisulfate (NaHSO4) and a proprietory product made of Ca-Fe silicate with a phosphoric acid coating was not different from the control (untreated litter). Aluminum sulfate (alum) and ferrous sulfate also reduced water soluble P concentrations in litter, whereas phosphoric acid greatly increased water-soluble P levels. The most effective compound evaluated with respect to reducing both ammonia loss and P solubility was alum.

Air Pollution↗
PubMed2003

Monitoring volatile and nonvolatile amines in dried and salted roes of tuna (Thunnus thynnus L.) during manufacture and storage.

Dried and salted roe, obtained from the reproductive organs of female tuna (Thunnus tynnus L.), is a typical fish-based food in the Mediterranean area of Spain. In the present study, we monitored the formation of volatile amines (trimethyamine nitrogen [TMA-N] and total basic volatile nitrogen [TBVN]) and nonvolatile amines (biogenic amines) in dried and salted tuna roe after processing and storage for 8 weeks at 4, 20, and 30 degrees C. The salting and drying process significantly increased the TBVN, cadaverine, tyramine, phenylethylamine, and tryptamine contents, and bacteria with histamine decarboxylase activity were detected both in raw and in dried and salted tuna roes. During storage of tuna roe, TMA-N and TBVN levels increased significantly after the fourth week of storage at 30 degrees C, whereas biogenic amine contents remained more or less constant. However, samples stored at 30 degrees C showed histamine formation after the first week of storage, with a concentration of < 50 ppm. The volatile and nonvolatile amine concentrations in tuna roe were below the consumer safety limit, with the exception of the total biogenic amine level in roe stored at 30 degrees C, which exceeded the European Community's recommended limit (300 ppm). These results indicate that in properly stored tuna roe, histamine formation will not represent a serious health risk to consumers unless the tuna roe has previously been mishandled.

Animals↗
PubMed2005

Fungal infections of fresh-cut fruit can be detected by the gas chromatography-mass spectrometric identification of microbial volatile organic compounds.

There is a large and rapidly growing market for fresh-cut fruit. Microbial volatile organic compounds indicate the presence of fungal or bacterial contamination in fruit. In order to determine whether microbial volatile organic compounds can be used to detect contamination before fruit becomes unmarketable, pieces of cantaloupe, apple, pineapple, and orange were inoculated with a variety of fungal species, incubated at 25 degrees C, then sealed in glass vials. The volatiles were extracted by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. Forty-five compounds were identified that might serve as unique identifiers of fungal contamination. Fungal contamination can be detected as early as 24 h after inoculation.

Consumer Product Safety↗
PubMed2005

Production of volatile compounds in cheese by Pseudomonas fragi strains of dairy origin.

Volatile compounds produced in cheese by five Pseudomonas fragi strains isolated from 1-day-old raw milk cheeses were investigated. Each strain was representative of a different biochemical group of isolates of identical phenotypic characteristics, according to identification with API 20 NE strips. The five strains were ascribed to the species P. fragi after 16S rRNA sequencing because of their high degree of coincidence with P. fragi ATCC 4973. In each of two experiments, carried out on different days, five cheeses were made at laboratory scale from pasteurized milk separately inoculated with approximately 10(5) CFU/ml of each P. fragi strain. After 12 days at 10 degrees C, mean counts of P. fragi strains were close to 10(10) CFU/g in the outer part of cheeses and close to 10(8) CFU/g in the inner part. A total of 131 volatile compounds, 49 of which were further characterized, were identified in cheeses by gas chromatography-mass spectrometry after extraction with a purge and trap apparatus. Abundances of compounds were generally higher in the outer part of cheeses. Production of volatile compounds was clearly strain dependent. Only two strains produced ethyl esters, and three produced nonethyl esters. Ethyl acetate, ethyl butyrate, ethyl caproate, methyl acetate, isopropyl acetate, and propyl tiglate were the major esters, and ethanol, 2-propanol, and 3-methyl butanol were the major alcohols. Undecene was the major hydrocarbon, dimethyl sulfide and methyl thiocyanate the major sulfur compounds, and 2-pentanone the major ketone. Two aromatic compounds, styrene and o-dichlorobenzene, were present in all cheeses.

Aldehydes↗
PubMed1979

[Effect of feeding pelleted feed on the level of volatile fatty acids in the digestive tract of sheep].

In an experiment with wethers we investigated the effect of complete pelleted feed ration on the concentration of volatile fatty acids in the rumen and intestinal tract. The animals consumed daily 1,300 g of dry matter of a diet which contained 41.81% of meadow hay, 25.28% of barley, 15.37% of sawdust, 14.98% of molasses, 1.32% of urea and 1.24% of a vitamin-mineral supplement for a period of six months. The pelleted diet increased the total amount of volatile fatty acids, the content of propionic acid and especially the content of butyric acid. There appeared a decrease in the ratio of acetate: propionate. On the basis of the greater energy efficiency of the volatile fatty acid production the animals fed pelleted feed showed a better energy balance. A higher VFA concentration was determined also in the large intestine and the cecum, which proves the importance of fermentation porcesses in these organs.

Animal Feed↗
PubMed1999

Identification of volatile compounds from cheek glands of lesser bandicoot rats and assessment of behavioural response for identified compounds.

Check gland secretions were collected from sexually mature male and female rats to identify the volatile compounds using gas chromatography linked mass spectroscopy with a modified head space technique. Twenty one volatile fractions including alkanes, aliphatic acids, esters and alcohols were found. Three compounds viz. 3-octen-1-ol (E) (I), cyclopentane undecanoic acid (II) and 2,4,6,8 tetramethyl-l-undecane (III) were present in very high concentrations in both male and female rats. In addition, the estrus female contained another compound, L-alanine, 1,1-dimethyl ethyl ester. On the basis of odour preference tests the compounds I, II and III were found to attract both male and female of the homotypic species. In contrast, the fourth compound present in the female attracts the opposite sex. The results suggest that the volatile fractions have unique function and the level of attraction varies from compound to compound.

Animals↗
PubMed2001

Repellency of volatile oils from plants against three mosquito vectors.

Volatile oils extracted by steam distillation from four plant species (turmeric (Curcuma longa), kaffir lime (Citrus hystrix), citronella grass (Cymbopogon winterianus) and hairy basil (Ocimum americanum)), were evaluated in mosquito cages and in a large room for their repellency effects against three mosquito vectors, Aedes aegypti, Anopheles dirus and Culex quinquefasciatus. The oils from turmeric, citronella grass and hairy basil, especially with the addition of 5% vanillin, repelled the three species under cage conditions for up to eight hours. The oil from kaffir lime alone, as well as with 5% vanillin added, was effective for up to three hours. With regard to the standard repellent, deet alone provided protection for at least eight hours against Ae. aegypti and Cx. quinquefasciatus, but for six hours against An. dirus. However, deet with the addition of 5% vanillin gave protection against the three mosquito species for at least eight hours. The results of large room evaluations confirmed the responses for each repellent treatment obtained under cage conditions. This study demonstrates the potential of volatile oils extracted from turmeric, citronella grass and hairy basil as topical repellents against both day- and night-biting mosquitoes. The three volatile oils can be formulated with vanillin as mosquito repellents in various forms to replace deet (N,N-diethyl-3-methylbenzamide), the most common chemical repellent currently available.

Animals↗
PubMed2001

[GC-MS analysis of volatile oil from Atractylodes chinensis].

OBJECTIVE: To determine chemical constituents of volatile oil from Atractylodes chinensis(D. C.) Koidz by quantitative with qualitative analysis. METHODS: By GC and GC/MS/DS analytical technology and SE-54 capillary column, the chemical constituents of volatile oil from Atractylodes chinensis(D. C.) Kiodz were systematically analyzed. RESULTS: 68 peaks were separated, which occupied over 90% of the total area of all chromatographic peaks. The 55 components were identified. CONCLUSION: The number of compoments of volatile oil from Atractylodes chinensis(D. C.) Koidz determined in this analysis, are two times as many as those reported in some literatures.

Asteraceae↗
PubMedDate not supplied

[Volatile oil of Anethum Graveolens L. as an inhibitor of yeast and lactic acid bacteria].

The antimicrobial activity of 25 volatile oils from aerial parts and seeds of dill (Anethum graveolens L.) of different geographical origin towards yeast Saccharomyces vini and lactic acid bacteria Lactobacterium buchneri was measured by serial dilutions. Volatile oils from mature seeds and green parts of the plants harvested at late vegetation phases showed the highest activity. The geographical origin of plants influenced insignificantly the antimicrobial activity of volatile oil.

Cell Division↗
PubMed2002

Analysis with gas chromatography and mass spectrography of volatile components of Ligusticum wallichii Franch extracted by CO2 supercritical fluid extraction in combination with molecular distillation.

OBJECTIVE: To evaluate the possibility of using the technique of CO2 supercritical fluid extraction (SFE) combined with molecular distillation (MD) to extract, separate and purify the volatile components of Ligusticum wallichii Franch, a Chinese herbal medicine. METHODS: SFE was employed to extract the volatile components of Ligusticum wallichii Franch, followed by MD of the product. Analysis of the chemical constituents of the extract both before and after MD was performed with gas chromatography (GC) in conjunction with mass spectrography (MS). RESULTS: There were 45 kinds of chemical constituents in the extract of Ligusticum wallichii Franch yielded from SFE, among which 39 were left after distillation by MD. Changes also took place in the content of the constituents in the extract after distillation. CONCLUSIONS: SFE combined with MD, a technique better than simple SFE, can be used to extract, separate and purify the volatile components of Chinese herbs.

Carbon Dioxide↗
PubMed2002

Polychlorinated biphenyls associated with fine particles (PM25) in the urban environment of Chile: concentration levels, and sampling volatilization losses.

Polychlorinated biphenyls (PCBs) were measured in fine particles (PM25, particles smaller than 2.5 microm in diameter) collected in two urban areas of Chile, Santiago and Temuco, during August and October 1998. A diffusion denuder sampling system was used for the collection of 19 samples. The concentrations of total PCBs (47 congeners) ranged from 672 to 1,790 pg/m3 in the city of Temuco and from 1,159 to 2,750 pg/m3 in Santiago. These concentrations are moderately higher than those observed in other urban areas around the world. High amounts of PCBs may volatilize from fine particles during aerosols sampling using conventional high-volume samplers. Average volatilization losses, determined by the diffusion denuder system, varied between 54 and 97%, showing a strong dependence on partial pressure of individual PCB congeners and air temperature. Overall, our results suggest that measurements of PCBs in the particulate phase of the atmosphere, by using conventional high-volume samplers, might be significantly underestimated because of volatilization losses. The underestimation of PCB and other toxic semivolatile organic compound (SOC) levels associated with fine particles in the urban environment may have consequences to the estimation of health risk posed by inhalation.

Air↗
PubMed2002

[Allelopathic potential of volatile oil from Mikania micrantha].

Mikania micrantha, an exotic plant species, is an important weed in south China. The volatile oil of the weed species had significant biological activities on plants and their pathogens, particularly Pyricularia grisea. The results showed that the seeding growth of 6 plant species decreased obviously when exposed to increasing concentration (200, 400, 800, 1600 mg.L-1) of the volatile oil. The fresh weight of all test plants decreased, and the emergence of all test plants delayed for 1-2 days under soil treatment (2500 g.hm-2). The inhibitory effect of volatile oil of M. micrantha at its medium concentration was the most strong on Pyricularia grisea; secondary on Fusarium oxysporum; but weak on Phytophthora nicotianae. The inhibitory rate was 53.38%, 28.66% and 18.69% for the three plant pathogens, respectively.

Ascomycota↗
PubMed2000

Role of volatile oil pretreatment and skin cholesterol on permeation of ion-paired diclofenac sodium.

This study was designed to investigate the influence of volatile oil pretreated skin on in vitro permeation from films containing ionized and dodecylamine ion-paired diclofenac sodium (DS). The involvement of skin cholesterol was investigated to determine its possible role in enhancing the permeation of ion-paired DS. Cardamom oil produced the maximum (10 x) in vitro permeation enhancement for ion-paired DS. The carrageenan induced rat paw oedema reduction (up to 12 hr) by cardamom oil was comparable to that of diclofenac injection (s c). Leaching of cholesterol from excised skin in addition to increased partition coefficient following volatile oil skin pretreatment appears to be responsible for in vitro permeation enhancement of DS. Whereas, a mild barrier perturbation effect due to altered cholesterol levels following pretreatment with volatile oils appears to increase the permeation of ion-paired DS across viable skin, thereby producing significant reduction of carrageenan induced paw oedema.

Administration, Cutaneous↗
PubMed1998

[Study on the Rheum palmatum volatile oil against HBV in cell culture in vitro].

The antiHBV effect of Rheum palmatum Volatile oil was studied by using 2215 cell line transfected with HBV DNA. At the same time MTT method was applied for the detection of cytoxicity of drugs, selecting acyclovir(ACV) as control medicine. It turns out that the toxic concentration of Rheum palmatum Volatile oil for 50% cells was (CD50) > 1.25 x 10(-1) g/L. When concentration was below 0.625 x 10(-1) g/L, the survival rate of cells was over 90%. The maximum inhibitory rates for HBsAg and HBeAg were 70.71 +/- 5.4% and 30.99 +/- 5.3% respectively. This shows Rheum palmatum Volatile oil possesses the effect of antiHBV in vitro.

Acyclovir↗
PubMed2000

[The influence of external stimulation on content and quality of volatile oil in Lignun Santali albi].

The authors analyzed the quality of Ligmum Santali Albi formed by the external stimulation of hormone and windburn by GC-MS-DS. The results showed that the content of volatile oil is 2.34% in the heart wood formed in 10 years tree age of Santalum album (SA) after 2 years stimulation continuously with a definite concentration of hormone, which is near to the 25 years tree age of SA in the same place. The GC-MS analysis showed that the content of santalol and other chemical components in volatile oil are similar to the 25 years tree age of SA. It is indicated that a definite concentration of hormone stimulated the SA may shorten the formation of the heart wood. The heart wood can be also formed by the broken branches after 2 years windburn, but its content of volatile oil is only 1/2 of the heart wood formed by hormone stimulation.

Age Factors↗
PubMed2001

[Studies on the chemical compound of volatile oils from various species of Citrus grandis].

The volatile oils in Citrus grandis from various species were compared by GC-MS. The results showed that the content of volatile oil from Citrus grandis and Citrus grandis (L.) Osbek var. tomentosa Hort. was from 0.7% to 0.9%. Over 30 chemical compounds were identified from the volatile oils and the types of the compounds were almost the same. But gamma-terpinen could not be identified from Citrus grandis which was rich in Citrus gransis (L.) Osbeck var. tomentosa Hort.

Citrus↗
PubMed2002

[Emission volatile organic compounds from new textile floor coverings].

The emission of formaldehyde and the other volatile organic compounds (toluene, styrene, 4-PC) and total volatile organic compounds (VOCs) from new textile floor coverings was measured with the use of environmental chamber (0.6 m3 capacity) in the following conditions: temperature 23 degrees C, relative humidity 45%, 1 exchange/hour and factor loading 1 m2 m-3. The formaldehyde was determined by using colorimetric method, VOCs by GC method. The tested carpets did not emit formaldehyde. The emission of other volatile organic compounds was very low and fulfill known requirements.

Air Movements↗
PubMed2003

[Chemical components of volatile oil from Mikania micrantha and its biological activity on insects].

The chemical components of volatile oil from Mikania micrantha were analyzed by GC/MS. Twenty-two compounds were identified, and monoterpenes and sesquiterpenes as well as alcohol and ketone with their derivatives were major components. Biological activity of volatile oil on insect was investigated. The results showed that the volatile oil had significant deterrent effect on oviposition of Plutella xylostella, Phyllotreta striolata and Phaedon brassicae at dose of 5-10 microliters.plant-1. They also possessed established contracting toxicity, and their rectifying reduce rates for Lipaphis erysimi were 50.0%, 59.86%, 62.51% at concentration of 500, 750, and 1000 mg.L-1, respectively. However, they had not fumigating toxicity for virginogeniae, L. erysimi, 2nd instar larvae of P. xylostella, and adult of P. striolata at concentration of 500 mg.L-1.

Animals↗