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In the period of the most expressed postirradiation (4 Gy) injury, the rats secreted volatile components capable of lowering the blood cells count in intact rats. This ability of the irradiated animals is not strictly specific for species since the depression effect on rats is exerted also by volatile components of irradiated mice. We suggest marking this phenomenon as postirradiation allelopathy.
Various materials, such as wall-paper, floor-wax, paint, multicolor wall-coat, air freshener and mothball were experimented in a simulated test chamber under constant selected temperature, humidity and air exchange rate. The relation between the total VOCs concentration and time was regressed by four emission models and the surface emission rate was calculated. The regressed results indicated the similarity among four emission models for the liquid materials with volatile-solvent such as paint and multicolor wall-coat. But for low volatile solid materials, such as wall-paper, floor-wax, mothball, the sink model and the empirical model were better than the dilution model and vapor pressure model. Only for air freshener, it was improper to the total VOCs concentration as a parameter.
OBJECTIVE: To extract and analyze the volatile constituents from the dried rhizomes of Heterosmilax yunnanensis(A) and H. chinensis(B). METHODS: Qualitative and quantitative analysis were made by GC-MS and GC. RESULTS: Forty and forty-seven constituents were identified from A and B respectively, the identification rates being 74.85% and 81.26% respectively. CONCLUSION: The volatile constituents of A and B are almost the same, but slightly different in content.
OBJECTIVE: To study the technology of supercritical-CO2 fluid extraction (SFE-CO2) for the volatile oils and saikosaponins in Bupleurum chinense. METHOD: Exploring the effects of pressure, temperature, extraction time, flow rate of CO2 and entrainers on the yield of the oils and saikosaponin-contained extracts; determining the optimum conditions for SFE-CO2; analyzing the oils by GC/MS and comparing the technology of SFE-CO2 with that of traditional steam distillation. RESULT: The optimum extraction conditions turned out to be--for volatile oils: pressure (EP) = 20 MPa, temperature (ET) = 30 degrees C, isolator I pressure (1P-I) = 12 MPa, temperature(1T-I) = 65 degrees C, isolator II pressure (1P-II) = 6 MPa, temperature (1T-II) = 40 degrees C, extraction time = 4 hours, and CO2 flow rate = 10-20 kg.(h.kg)-1 crude drug; for saikosaponins: EP = 30 MPa, ET = 65 degrees C, 1P I = 12 MPa, 1T I = 55 degrees C, 1P II = 6 MPa, 1T II = 43 degrees C, extraction time = 3 hours, entrainer = 60% ethanol, and CO2 flow rate = 20-25 kg.(h.kg)-1 crude drug. CONCLUSION: SFE-CO2 excels the traditional steam distillation in raising yield and reducing extraction time. The oils are composed of 22 constituents including caproaldehyde, and the saikosaponins can only be extracted with the help of entrainers under higher pressure and temperature.
The volatile oil from Lysimachia trientaloides Hemsl. was obtained by steam distillation. The chemical constituents were separated and identified by gas chromatography-mass spectrometry (GC-MS). The relative contents in the volatile oil were determined by peak area normalization. The yield of oil by steam distillation was 0.11%, and 40 chemical constituents were separated and identified. Terpenic series and their oxo-derivatives are major chemical constituents in the oil. The main compounds were patchouli alcohol(22.54%), L-bornyl acetate(16.17%), gamma-gurjunene(3.27%), delta-guaiene(2.62%), nerolidol(2.02%), linalool(1.99%) and palmitic acid(1.96%).
The volatile components in root of Ficus hitra Vahl were analyzed by GC-MS, the results suggested that the main volatile components in root of Ficus hitra Vahl were Hexadecanoic acid, Oleic acid, Linolic acid and Ethyl Acetate; its ether extract contains Isopsoralen and Bergapten. Coumarins should be one of the effective sections in root of Ficus hitra Vahl.
OBJECTIVE: To determine the volatile oil of the leaves from Hypericum perforatum L.. METHOD: The essential oil was obtained by simultaneous distillation and solvent extraction. The chemical components were seperated and identified by GC-MS. The relative contents in the volatile oil were determined by area nomalization. RESULTS: 54 chemical constituents were separated and identified representing 92.32% of the total contents. CONCLUSION: Sesquiterpenes are major chemical constituents in the oil from the leaves of Hypericum perforatum L.. They are very different from those of the essential oil from the same species from the other country.
The constituents of the volatile oil of Pogostemon cablin collected from Wanning city, Hainan province and the influence owing to different collection time were undertaken by GC/MS combination technology. The results showed that main compounds was patchouli alcohol in stem oil and leaf oil, its contents were respectively 36.06% and 37.74%; pogostone was poor, its contents in stem oil and leaf oil were respectively 17.08% and 0.85%; the contents of ten compounds were over 1%, which was respectively beta-patchoulene, beta-elemene, transcaryophyllene, delta-guaiene, seychellene, alpha-patchoulene, aciphyllene, alpha-guaiene, patchouli alcohol and pogostone; the contents of volatile oil from June to August were respectively 0.8%, 0.7% and 0.6%; patchouli alcohol, higher in July and June(42.62% and 40.84%), lower in August(31.40%).
OBJECTIVE: To study optimum inclusion process conditions for volatile oil from Aucklandia lappa. METHODS: The study was carried out with orthogonal design. The process conditions were studied by determining the utilization ratio of volatile oil from Aucklandia lappa, the oil-bearing rate and extract ratio of inclusion compound. RESULTS: The optimum preparation conditions for inclusion were established as: oil: beta-CD was 1:8, the inclusion temperature and time were at 40 degrees C and for 1 h respectively, the utilization ratio of oil is 87.1%. CONCLUSION: The method can be used for production of beta-CD on a large scale.
OBJECTIVE: To study the volatile oils in flower and stem of Lonicera japonica. Thunb. METHOD: GC-MS. RESULTS: 36 constituents are isolated and identified in all, of which 28 from Flos Lonicerace and 26 from Caulis Lonicerae. 18 compounds are found simultaneously in both crude drugs and they account for 85.23%, 83.42%, respectively. Palmatic acid and linoleic acid are the highest principles. CONCLUSION: The volatile oils are highly similar to each other.
Volatile oil was extracted from Cuminum cyminum L. by using steam distillation. More than sixty peaks were separated and 49 compounds were identified by gas chromatography-mass spectrometry (GC-MS). The relative amounts of the components were determined by area normalization method. Among the 49 compounds identified, there were 16 hydrocarbons and 32 oxygenated compounds. The main compnents were cuminal and safranal (accounting for 32.26% and 24.46% respectively in the components identified). The other nine compounds with contents all over 1%, were monterpenes, sesquiterpenes, aromatic aldehydes and aromatic oxides etc. The other components with relatively small amounts were chiefly terpenes, terpenols, terpenals, terpenones, terpene esters and aromatic compounds. It is good to separate polar and apolar components in the volatile oil from Cuminum cyminum L. on the GC capillary column of moderate polarity.
A variety of food products containing nitrite were analyzed for 14 volatile N-nitrosamines by using a method demonstrated to be sensitive to 10 ppb. A total of 121 food samples were screened for volatile N-nitrosamine content. N-Nitrosopyrrolidine was confirmed in fried bacon at levels up to 139 ppb. N-Dimethylnitrosamine, N-nitrosopyrrolidine, and N-nitrosopiperidine were also confirmed in spice-cure mixtures at levels ranging from 50 to 2000 ppb.
Effects of the volatile oil constituents of Nigella sativa, namely, thymoquinone (TQ), p-cymene and alpha-pinene, on carbon tetrachloride (CCl4-indued acute liver injury were investigated in mice. A single dose of CCl4 (15 microl/Kg i.p.) induced hepatotoxicity 24 h after administration manifested biochemically as significant elevation of the enzymes activities of serum alanine transaminase (ALT, EC:2.6.1.2), asparate transaminase (AST, EC:2.6.1.1) and lactate dehydrogenase (LDH, EC: 1.1.1.27). The toxicity was further evidenced by a significant decrease of non-protein sulfhydryl(-SH) concentration, and a significant increase of lipid peroxidation measued as malondialdhyde (MDA) in the liver tissues. Administration of different doses of the TQ (4, 8, 12.5, 25 and 50 mg/Kg i.p.) did not alter the chosen biochemical parameters measured, while higher doses of TQ were lethal. The LD50 was 90.3 mg/Kg (77.9-104.7, 95% CL). Pretreatment of mice with different doses of TQ 1 h before CCl4 injection showed that the only dose of TQ that ameliorated hepatotoxicity of CCl4 was 12.5 mg/Kg i.p. as evidenced by the significant reduction of the elevated levels of serum enzymes as well as hepatic MDA content and significant increase of the hepatic nonprotein sulfhydryl(-SH) concentration. Treatment of mice with the other volatile oil constituents, p-cymene or alpha-pinene did not induce any changes in the serum ALT measured. In addition, i.p. administration of these compounds 1 h before CCl4 injection, did not protect mice against CC4-induced hepatotoxicity. The results of the present study indicate that TQ (12.5 mg/Kg, i.p.) may play an important role as antioxidant and may efficiently act as a protective agent against chemically-induced hepatic damage. In contrast, higher doses of TQ were found to induce oxidative stress leading to hepatic injury.
Material and migration tests of food-contact plastic wares made of polystyrene were carried out. The average concentration of volatile substances (sum of toluene, ethylbenzene, isopropylbenzene, n -propylbenzene, and styrene) in materials was 861 +/- 692 ppm. Styrene was observed in 95% of 19 samples. alpha-Methylstyrene, which is one of the material compounds of polystyrene, was detected in one sample. Release of volatile substances into n-heptane was not observed at the detection limits of 0.1 ppm.
After 24, 48 and 72 hours' treatment of cells of SGC-823 gastric carcinoma in cell cultures with ginseng volatile oil, glycogen, succinate dehydrogenase and DNA in single cells were measured quantitatively with MPV2 microscope photometer. The results show that the inhibition of cancer cell growth by ginseng volatile oil may be due to the action of metabolism of DNA, carbohydrates and energy.
The effect of staging the sludge bed on volatile fatty acid degradation by sulfidogenic reactors was evaluated in a baffled reactor. In a 5.4 l baffled reactor, containing three equal compartments, a volatile fatty acid (VFA) mixture (acetate:propionate:butyrate ratio 1:2:2 on COD basis; pH 8) was treated under mesophilic (30 degrees C) and sulfidogenic (COD:SO4(2-) ratio: 0.5) conditions for 38 days. At a specific sludge loading rate of 0.50 g COD.gVSS(-1) x d(-1), a COD and sulfate removal of 85% and 30%, respectively, was obtained. In the baffled reactor, staging of the sulfidogenic VFA degradation occurred. Propionate and butyrate were mainly degraded in the first compartment. Their degradation was incomplete, resulting in elevated acetate concentrations in compartment I. In the second and third compartment of the baffled reactor, a net degradation of acetate took place. Acetate was the sole substrate present in compartment III and residual acetate concentrations of about 200 mg/l were present in the effluent at a specific sludge loading of 0.50 g COD x gVSS(-1) x d(-1). Sludges with different maximum specific VFA and acetate degrading activities developed in the first and second compartment. These maximal specific activities were almost equal for sludge present in compartment II and III.
OBJECTIVE: To find an inhibitor to reduce the volatilization of formalin. METHOD: The saturated solution of sodium hydrosulphite (SHS) was sprayed on the surface of the anatomy specimens, then the concentration of formaldehyde in the air was tested. RESULTS: The concentration of formaldehyde in the air of SHS sprayed group [(3.10 +/- 1.22) mg/m3] was significantly lower than that of the control group [(8.36 +/- 4.11) mg/m3, P < 0.01]. CONCLUSION: SHS may be a volatilization inhibitor for formalin, which could reduce the concentration of formaldehyde in the air.
In 10 German Black and White heifers metabolic stress reactions were induced by intravenous infusion of propionate and butyrate to demonstrate possible effects of prior medication with butafosfane. This investigation included a preliminary feeding period, followed by 18 hours of feed withdrawal, premedication with butafosfane or placebo and infusion of volatile fatty acids. Reactions were assessed by monitoring biochemical and clinical parameters. A total of 19 blood samples per series were taken in which the concentrations of glucose, free fatty acids, volatile fatty acids, beta-hydroxybutyrate, cortisol and insulin were measured. Clinical parameters recorded included heart rate and respiratory rate. During loading with propionate effects of butafosfane on plasma levels of cortisol and insulin could be demonstrated. The differences noted in the other parameters were only insignificant. The loading test chosen is suitable for the demonstration of effects of butafosfane on metabolic parameters which could hardly be influenced by this substance in unstressed animals.