Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 ...Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 species of VOCswere simultaneously determined in surface soil samples collected from 63 chemical industrial parks(CIPs)across China.The results showed that the total VOC concentrations ranged from 7.15 to 1842 ng/g with a mean concentration of 326 ng/g(median:179 ng/g).Benzene homologs and halogenated hydrocarbons were identified as the dominant contaminant groups.Positive correlations between many VOC species indicated that these compounds probably originated from similar sources.Spatially,the hotspots of VOC pollution were located in eastern and southern China.Soils with higher clay content and a higher fraction of total organic carbon(TOC)content were significantly associated with higher soil VOC concentrations.Precipitation reduces the levels of highly water-soluble substances in surface soils.Both positive matrix factorization(PMF)and principal component analysis-multiple linear regression(PCA-MLR)identified a high proportion of industrial sources(PMF:59.2%and PCA-MLR:66.5%)and traffic emission sources(PMF:32.3%and PCA-MLR:33.5%).PMF,which had a higher R^(2) value(0.7892)than PCA-MLR(0.7683),was the preferred model for quantitative source analysis of soil VOCs.The health risk assessment indicated that the non-carcinogenic and carcinogenic risks of VOCs were at acceptable levels.Overall,this study provides valuable data on the occurrence of VOCs in soil from Chinese CIPs,which is essential for a comprehensive understanding of their environmental behavior.展开更多
Volatile flavor components in foods are the key quality parameters. The researchers conducted in-depth research on sesame oil, peanut oil, rapeseed oil, sunflower oil, sesame paste and peanut butter, etc. However, the...Volatile flavor components in foods are the key quality parameters. The researchers conducted in-depth research on sesame oil, peanut oil, rapeseed oil, sunflower oil, sesame paste and peanut butter, etc. However, there is no comprehensive summary about the flavor of roasted oilseeds and their products. The occurrence and the formation mechanisms of the main volatile flavor substances,and the impacts of processing factors are discussed in this review, which may provide references for further research on volatile flavor compounds, identification and evaluation of specific products and development of new products.展开更多
[Objectives]To analyze the composition of volatile oils from mango leaves from different producing areas.[Methods]The volatile oils in mango leaves from different areas was extracted by steam distillation,and the GC-M...[Objectives]To analyze the composition of volatile oils from mango leaves from different producing areas.[Methods]The volatile oils in mango leaves from different areas was extracted by steam distillation,and the GC-MS method combined with retention index and peak area normalization method was used for qualitative and quantitative analysis.[Results]The volatile oils of mango leaves in southern provinces contained high content of terpenes,such asα-gurjunene(18.39%-34.13%),(+)-viridiflorene(8.95%-16.30%)and(E)-β-ocimene(3.49%-7.63%).The volatile oils components of mango leaves were significantly different in different provinces,for example,mango leaves produced in Hainan Province contained a large amount ofβ-selinene(23.00%),but not in other provinces.[Conclusions]The origin had a great influence on the composition and contents of volatile oils in mango leaves.展开更多
Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used ...Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures（silty,clayey, and sandy soils） along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform（TCM） and trichloroethylene（TCE）. Mechanical soil aeration was effective for remediating VCHs（removal efficiency 〉 98%）. The volatilization process was described by an exponential kinetic function.In the early stage of treatment（0–7 hr）, rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.展开更多
Leaf and stem essential oils of Lonchocarpus cyanescens Benth., (Fabaceae) were obtained by hydro-distillation, using all-glass apparatus adapted to British Pharmacopeia specifications with yields of 0.03% and 0.17% r...Leaf and stem essential oils of Lonchocarpus cyanescens Benth., (Fabaceae) were obtained by hydro-distillation, using all-glass apparatus adapted to British Pharmacopeia specifications with yields of 0.03% and 0.17% respectively. The oils were investigated by GC and GC-MS analyses. Results show seven compounds were responsible for 90.4% of leaf;eleven compounds responsible for 97.6% of stem volatile oils. Phytol (62.5%) and hexadecanoic acid (12.4%) dominate the leaf oil;octadecenoic (24.1%) and hexadecanoic acids (17.2%) are predominant in the stem oil. Phytochemical screening of stem, leaf, and root methanol extracts of Lonchocarpus cyanescens reveal presence of following seven classes of metabolites: saponin, tannin, steroid, terpenoid, cardiac glycosides, phlobatannins and flavonoids. Partitioning of methanol extract from dried leaf of it with ethylacetate gave fraction, which was chromatographed using gradient elution. TLC with high Rf was used in monitoring elution. Two white crystalline solids eluted at 5% and 10% ethylethanoate in hexane, were re-crystallized and characterized. They were subjected to Infra-Red spectra, mass spectrometry (ESI technique), 1H and 13C-NMR analyses, which confirmed they are triterpenoids. Above mentioned metabolites may be responsible for literature acclaimed bio-activities L. cyanescens display [anti-inflammatory, anti-arthritic, anti-microbial effects]. This paper presents details of above results which are new in literature.展开更多
[Objectives] To study the effects of volatile oils of Sichuan Citrisarcodactylis fructus on proliferation and apoptosis of MCF-7human breast cancer cells.[Methods]CCK-8 method was used to measure the cell proliferatio...[Objectives] To study the effects of volatile oils of Sichuan Citrisarcodactylis fructus on proliferation and apoptosis of MCF-7human breast cancer cells.[Methods]CCK-8 method was used to measure the cell proliferation,the flow cytometry was used to measure changes in cell cycle,Western blot was used to detect p53 and cyclin D1 activity changes,TUNEL method was used to measure percentage of apoptotic cells,inverted phase contrast microscope and transmission electron microscope were used to observe morphology of MCF-7 cells treated with different concentrations.[Results]When the concentration was 5-50 μmol/L,the cell proliferation inhibition rate increased significantly(P <0. 05),G2/M phase decreased significantly( P < 0. 05),eventually disappeared completely,G1 phase significantly increased with time and concentration( P < 0. 05),finally reached 90. 0%; the activity of cyclin D1 significantly declined( P < 0. 05),while the activity of p53 had no significant change( P > 0. 05). The apoptotic rate of MCF-7 cells significantly increased with the extension of time( P < 0. 05). At6 h,12 h and 24 h of action time,the apoptotic rate of MCF-7 cells significantly increased with the increase in volatile oil concentration(P <0. 05). Morphological observation showed that the apoptosis of MCF-7 cells was obvious.[Conclusions]The volatile oils of Citrisarcodactylis fructus have obvious inhibition of proliferation of MCF-7 cells and function of inducing apoptosis,and the effects took on the dose and time dependent. 5-50 μmol/L volatile oil of Sichuan Citrisarcodactylis fructus can inhibit the proliferation of MCF-7 cells and induce the apoptosis of MCF-7 cells through inhibiting the cyclin D1.展开更多
With a great difference in therapeutic effects of Mahuang(MH, the stems of Ephedra sinica) and Mahuanggen(MHG, the roots of Ephedra sinica), chemical differences between MH and MHG should be investigated. In the prese...With a great difference in therapeutic effects of Mahuang(MH, the stems of Ephedra sinica) and Mahuanggen(MHG, the roots of Ephedra sinica), chemical differences between MH and MHG should be investigated. In the present study, gas chromatography-mass spectrometry(GC-MS)-based plant metabolomics was employed to compare volatile oil profiles of MH and MHG. The antioxidant activities of volatile oils from MH and MHG were also compared. 32 differential chemical markers were identified according to the variable importance in the projection(VIP) value of orthogonal partial least squares discriminant analysis(OPLS-DA) and P value of Mann-Whitney test. Among them, chemical markers of tetramethylpyrazine(TMP) and α-terpineol were quantified. Their contents were much higher in most MH samples compared with MHG. The antioxidant assay demonstrated that MH had significantly higher free radical-scavenging activity than MHG. Although MH and MHG derived from the same medicinal plant, there was much difference in their volatile oil profiles. MH samples had significantly higher content of two reported pharmacologically important chemical markers of TMP and α-terpineol, which may account for their different antioxidant activities.展开更多
Objective:To determine the chemical composition of essential oils and lipid constituents of Ballola andreuzziana(B.andreuzziana),Teucrium zanonii(T.zanonii) and Verbena tenuisecta(V. tenuisecta) growing in Libya,and t...Objective:To determine the chemical composition of essential oils and lipid constituents of Ballola andreuzziana(B.andreuzziana),Teucrium zanonii(T.zanonii) and Verbena tenuisecta(V. tenuisecta) growing in Libya,and to test the antibacterial activity of different extracts of Teucrium zanonii.Methods:The volatile oils of all plants were extracted by hydrodistillation method and analyzed by GC/MS method.The lipid constituents of plants were obtained by extraction with petroleum ether and fractionated into fatty alcohols,fatty acids and unsapoinfiable matters. Antibacterial activity of T.zanonii extracts and antioxidant activity of different extracts of T. zanonii were also studied.Results:The volate oil of B.andreuzziana was found to consists of 20 compounds in which caryophyllin is the main one(63.1%),the volatile oil of T.zanonii consists of 74 compounds in which germacrene-D was the main compound,while the volatile oil of V. tenuisecta consists of 13 compounds with l-octen-3- ol as a major constituent(52.87%).The study of antimicrobial activity of different extracts of V.tenuisecta showed that,both methanol and butanol extracts exhibited the highest activity against Mycobacterium phlei(M.pblei) and Candida albicans(C.albicans) respectively,while petroleum ether,fatty alcohols and unsaponifiable fractions had no antimicrobial activity against all the tested microorganisms. Investigation of the antioxidant activity of different extracts of T.zanonii using DPPH method proved that,the ethyl acetate and butanol fractions showed the highest activity where the inhibition percentage(1%) are 93.6 and 92.1 respectively.Conclusions:This is the first report about the volatile oils of these plants where T.zanonii have the highest content and the highest number of the identified compounds.The study of antioxidant T.zanonii extracts proved that,the ethyl acetate,butanol and aqueous extracts have the highest antioxidant activity.Methanol and butanol extracts of V.tenuisecta exhibited the highest activity against M.phlei and C.albicans respectively.展开更多
A comparison study has been performed in hempseed oils (HSO) extracted from different cultivars in Bama region. Squeezing properties, chemical compositions, thermal stability and flavor profile of pressed HSO were det...A comparison study has been performed in hempseed oils (HSO) extracted from different cultivars in Bama region. Squeezing properties, chemical compositions, thermal stability and flavor profile of pressed HSO were determined in this study. Results indicated that there were no significant differences in crude fat, protein, fiber of different hempseeds and fatty acid composition in HSOs. Hempseeds with small size and dark-colored peel have lower squeezing oil yield than big ones. Average content of total phytosterol, tocopherol and phenol in HSO from small seeds were 872.0 mg/100 g, 124.1 mg/100 g and 15.5 mg SA/100 g respectively. Thermal oxidation by differential scanning calorimetry (DSC) revealed three step oxidation of HSO with mean onset and oxidation temperature at 124oC and 135-315oC. Oxidation temperature of HSO from small seeds was higher than that from big seeds (big size and light-colored peel). Main volatile ingredients in HSO contained 11 kinds of monoterpene and 7 kinds of sesquiterpene. Volatile terpene content in HSO from small seeds was nearly 30% higher than that of big seeds. Quality of HSO with different peel feature has significant difference in squeezing yield, thermal stability and volatile flavors. This work may be useful to produce high quality hempseed oils through quality evaluation.展开更多
Rosa x alba is cultivated almost exclusively for the production of aromatic water and fruits widely used as ingredients in some traditional food preparations sold commercially.Results of the proximate and elemental an...Rosa x alba is cultivated almost exclusively for the production of aromatic water and fruits widely used as ingredients in some traditional food preparations sold commercially.Results of the proximate and elemental analyses revealed that flowers exhibited higher moisture content while the dry matter content was higher in leaves.Total fat and ash was higher in fruits when compared with leaves and flowers.All studied organs were found to be rich in essential mineral such as K,Ca,P and Mg.Qualitative and quantitative analysis of the volatile oils revealed different composition patterns between organs.Linalool and geraniol were found as major constituents of the leaf oil whereas 2-phenethyl alcohol and eugenol were the major constituents of the floral oil.In contrast,fruits showed very distinct composition and alkanes/alkenes were found to have the major contribution.The present composition could justify the traditional use of Rosa x alba which could be considered as a potential source of essential minerals and volatile constituents.展开更多
Azadirachta indica A. Juss (neem, family Meliaceae) is a reputable medicinal plant. Various parts of the plant are used as a remedy against different ailments, as a natural pesticide, as raw material in the cosmetic i...Azadirachta indica A. Juss (neem, family Meliaceae) is a reputable medicinal plant. Various parts of the plant are used as a remedy against different ailments, as a natural pesticide, as raw material in the cosmetic industry, and for marking other commodities. The seed oil is a major product of the plant and its quality depends on the seed quality and extraction methods employed. In this study, the chemical profile of NIPRDNEEM oil is compared with that of other brands of neem seed oils by using gas chromatography-mass spectrometry (GC-MS) and chemometrics. The fatty acid identified in NIPRDNEEM oil were: oleic acid (34.09%), stearic acid (11.4%), linoleic acid (15.94%), palmitic acid (23.4%), arachidic acid (0.73%), and the other compounds were: 1-Monolinoleoylglycerol trimethylsilyl ether (0.95%) and farnesyl alcohol (13.20%). The branded oils were composed predominantly of oleic acid (13.50% - 26.76%), palmitic acid (6.88% - 11.99%), linoleic acid (7.32% - 11.17%), stearic acid (4.29% - 13.08%), and arachidic acid (0.53% - 1.27%). The unbranded oil contained oleic acid (30.04%), stearic acid (14.91%), linoleic acid (14.62%), palmitic acid (12.34%), and arachidic acid (0.93%). Stigmasterol, stigmasterol acetate, and sitosterol were the sterols identified in the oils. Characterization of the fatty acid profile of neem seed oil is vital for industrial and economic purposes. The fatty acids profile of the NIPRDNEEM oil and other neem seed oil were comparable. Both PCA plots and HCA dendrogram from the chemometric analysis shows three main grouping of all samples. While NIPRDNEEM and the local neem oil were grouped, suggesting a high degree of resemblance of both samples.展开更多
[Objectives]This study was conducted to compare and analyze the chemical constituents of the volatile oils of the Yao medicine Thunbergia grandiflora from different habitats.[Methods]A quartz capillary column DB-1MS,a...[Objectives]This study was conducted to compare and analyze the chemical constituents of the volatile oils of the Yao medicine Thunbergia grandiflora from different habitats.[Methods]A quartz capillary column DB-1MS,an EI ion source and a quadrupole mass analyzer were used for analysis.The chromatographic and mass spectrum information obtained was automatically retrieved and analyzed by data processing system and its memory spectrum library(Nist.08).The relative content of each chemical component in the volatile oil was determined by the peak area normalization method.[Results]Forty nine chromatographic peaks were isolated from the sample produced in Shitun,Bailongtan Town,Mashan County,and 24 chemical constituents were identified,accounting for 88.78% of the total volatile oil.Forty nine chromatographic peaks were isolated from the sample produced in Hongdu Village,Chengjiang Town,Duan County,and 30 chemical constituents were identified,accounting for 88.38% of the total volatile oil.Forty eight chromatographic peaks were isolated from the sample produced in Longwan Township,Du'an County,and 25 chemical constituents were identified,accounting for 80.01% of the total volatile oil.Nine chemical constituents were common to the volatile oils of the samples from the three habitats.[Conclusions]It could be seen that the main components of volatile oils from T.grandiflora produced in different areas are different.展开更多
Six types of termites＇ baits （cartoon, rough tissues, soft toilet tissues, acacia wood, saw dust of building wood and sackcloth） were elicited variable degree of attraction toward Anacanthotermes ochaceus, where th...Six types of termites＇ baits （cartoon, rough tissues, soft toilet tissues, acacia wood, saw dust of building wood and sackcloth） were elicited variable degree of attraction toward Anacanthotermes ochaceus, where the best one was cardboard, followed by soft and rough toilet tissue at mono-choice and multiple-choice tests. Chemical analysis showed that there were variations in the chemical constituents （lignin, cellulose, N, H and C） of the six baits studied. On the other hand, olfactory reactions of harvester termites toward eight volatile oils （four natural medical plants and four commercial terpines） were repellent, but the most repellent one was cineol and the least one was clove oil. The most tested oils were caused inhibition in feeding, except cedar wood. The most toxic oils were cineol followed by thymol.展开更多
The rising risk of synthetic preservatives as antimicrobial agent has increased,leading to potential allergic reactions,intoxications,cancer,and other degenerative diseases.As a result,essential oils(EOs),recognized a...The rising risk of synthetic preservatives as antimicrobial agent has increased,leading to potential allergic reactions,intoxications,cancer,and other degenerative diseases.As a result,essential oils(EOs),recognized as natural antimicrobial agents due to their extensive antibacterial properties,have gained attention.However,their industrial applicability is hindered by challenges such as volatility,poor water solubility,oxidation potential,photodegradation,and thermal instability.Nano-encapsulation has emerged as a transformative solution for delivering essential oils,enhancing their stability,bioavailability,and targeted administration.This review explores the use of nano-encapsulated essential oils in combating bacteria,focusing on their mechanisms of action and potential advancements for the food preservation industry.Various nano-encapsulation methods,including liposomes,nanoemulsions,polymeric nanoparticles,and biopolymers like chitosan and alginate,have shown promise in overcoming the limitations associated with EOs.展开更多
Chrysanthemum and Opisthopappus are genera that include perennial herbaceous floral species,including excellent varieties with strong fragrances resulting from long-term artificial selection.Thus,they are ornamentally...Chrysanthemum and Opisthopappus are genera that include perennial herbaceous floral species,including excellent varieties with strong fragrances resulting from long-term artificial selection.Thus,they are ornamentally and economically important flower resources.In this study,a water distillation method was used to extract essential oils from the inflorescences of Chrysanthemum and Opisthopappus wild resources and hybrid progeny with high essential oil contents(Chrysanthemum morifolium'xiangjin',C.morifolium'xiangyun',C.morifolium'xinjiboju',Opisthopappus taihangensis,Opisthopappus longilobus,Chrysanthemum lavandulifolium,and C.morifolium'minghuangju').The essential oil extraction rates were as follows:1.17‰,2‰,1.67‰,2.17‰,0.43‰,1‰,and 1.17‰.On the basis of HS-SPME-GC-MS(Headspace solid phase microextraction-gas chromatography-mass spectrometry),225 volatile compounds were detected in the seven analyzed essential oil samples.Each essential oil had a relative volatile component content exceeding 0.3.The three most abundant compounds were olefins(46 types),alcohols(34 types),and esters(18 types).The volatile components with relatively high contents included thymol,D-camphor,pinene,eucalyptol,2-terpineol,terpineol,trans-caryophyllene,andβ-elemene.These volatile compounds have strong biological activities and are useful components of medicines and daily-use products.An evaluation of their antibacterial effects demonstrated that the essential oils of C.'xiangjin',C.'xiangyun',C.'xinjiboju',O.taihangensis,O.longilobus,and C.'minghuangju'inhibited the growth of Escherichia coli.The C.lavandulifolium essential oil inhibited the growth of Pectobacterium carotovorum.The results of this study will provide researchers with an important theoretical basis for the development and application of Chrysanthemum and Opisthopappus essential oils.展开更多
Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs...Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients(600-1690ma.s.l.)in the Nanling Mountains of southern China.Composition characteristics as well as seasonal and altitudinal variations were analyzed.Standardized emission rates and canopyscale emission factors were then calculated.Results showed that BVOCs emission intensities in the wet season were generally higher than those in the dry season.Monoterpenes were the dominant BVOCs emitted from most broad-leaved trees,accounting for over 70%of the total.Schima superba,Yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation potentials.The localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols fromNature(MEGAN),while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the model.Our results can be used to update the current BVOCs emission inventory in MEGAN,thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China.展开更多
The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the opt...The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the optimal way to deploy injection-production well networks are critical issues that must be urgently addressed for efficient oilfield development.Experimental research on the mixed-phase displacement mechanism through gas injection into indoor formation fluids was conducted to guide the efficient development of gas injection in oil fields.We established a model of dual-medium reservoir composition and researched the deployment strategy for a three-dimensional well network for gas injection development.The coupling relationship between key influencing factors of the well network and fracture development was also quantitatively analyzed.The results show that the solubility of the associated gas and strong volatile oil system injected into the BZ oilfield is high.This high solubility demonstrates a mixed-phase displacement mechanism involving intermediate hydrocarbons,dissolution and condensation of medium components,and coexistence of extraction processes.Injecting gas and crude oil can achieve a favorable mixing effect when the local formation pressure is greater than 35.79 MPa.Associated gas reinjection is recommended to supplement energy for developing the highly volatile oil reservoirs in the fractured buried hills of the BZ oilfield.This recommendation involves fully utilizing the structural position and gravity-assisted oil displacement mechanism to deploy an injection-production well network.Gas injection points should be constructed at the top of high areas,and oil production points should be placed at the middle and lower parts of low areas.This approach forms a spatial threedimensional well network.By adopting high inclination well development,the oil production well forms a 45°angle with the fracture direction,which increases the drainage area and enhances single-well production capacity.The optimal injection-production well spacing along the fracture direction is approximately 1000 m,while the reasonable well spacing in the vertical fracture direction is approximately 800 m.The research results were applied to the development practice of the buried hills in the BZ oilfield,which achieved favorable development results.These outcomes provide a valuable reference for the formulation of development plans and efficient gas injection development in similar oil and gas fields in buried hills.展开更多
The fall armyworm(Spodoptera frugiperda)is an invasive species and a destructive pest of maize,which significantly impacts native species and communities via complex mechanisms like competition for resources.However,t...The fall armyworm(Spodoptera frugiperda)is an invasive species and a destructive pest of maize,which significantly impacts native species and communities via complex mechanisms like competition for resources.However,the interaction between S.frugiperda and local pests remains unclear.In this study,we determined that Oriental armyworm(Mythimna separata)females with different mating status displayed different approach-avoidance behaviors towards maize which was infested by S.frugiperda larvae.The virgin M.separata females were repelled,while the mated females were attracted by the S.frugiperda-infested maize.To further understand the olfactory mechanism of this phenomenon,seven volatiles induced by S.frugiperda in maize were characterized by gas chromatography and mass spectrometry(GC-MS),including trans-2-hexenal,linalool,trans-β-farnesene,cis-3-hexenyl acetate,β-caryophyllene,trans-α-bergamotene,and isopentyl acetate.Additionally,electrophysiological and behavioral assays of the seven compounds were performed using both virgin and mated females of M.separata.We determined that virgin and mated females displayed different responses to the herbivore-induced plant volatile(HIPV).Trans-β-farnesene was the core compound for repelling virgin females,and trans-2-hexenal was the key attractant for oviposition in mated female M.separata individuals.These findings help our comprehension of the relationships between maize pests and offer new possibilities for controlling them by olfactory-based strategies.展开更多
This study examined the EAG(Electroantennogram)responses of Stilpnotia candida to a mix of host plant volatiles and to provide a foundation for the development of plant-derived attractants.During the peak period of ad...This study examined the EAG(Electroantennogram)responses of Stilpnotia candida to a mix of host plant volatiles and to provide a foundation for the development of plant-derived attractants.During the peak period of adult eclosion,gas chromatography–mass spectrometry analyzed and identified the volatiles emitted by Populus×beijingensis found in Xizang.Based on the preliminary EAG experiments and the GC‒MS results,a blending scheme was developed.EAG and Y-tube-olfactometry were employed to measure the electrophysiological and behavioural responses of unmated males and females 24 h after eclosion 10 blends of volatiles derived from five host plants.The GC–MS analysis revealed 22 volatile compounds from Populus×beijingensis leaves,composed of esters,hydrocarbons,terpenoids,alcohols,phenols,and ether.The results indicated that all 10 blending schemes produced EAG responses in mature S.candida.The concentration thresholds were between 1 and 10μg·μL^(-1),above the optimal concentration,and a corresponding decrease in EAG was observed.According to intergroup comparisons,mature S.candida had more pronounced EAG responses.Under different concentrations,there were significant differences in the EAG from male and female S.candida to each blending scheme.Behavioural response tests indicated that schemes 2,7,and 8 exhibited significantly greater attractiveness to adult S.candida.The combined results from the EAG and behavioral response experiments demonstrated that unmated male and female adult S.candida have varying degrees of sensitivity to the volatile compounds from the 10 blending schemes specific to Xizangan Populus×beijingensis.Schemes 2,7,and 8 showed robust EAG responses and attractive behavioural responses to both male and female adult S.candida.展开更多
The development of alternative therapies to treat chicken coccidiosis has become a hot topic because of the widespread use of conventional medicines.This study aimed to investigate the effectiveness of eugenol in trea...The development of alternative therapies to treat chicken coccidiosis has become a hot topic because of the widespread use of conventional medicines.This study aimed to investigate the effectiveness of eugenol in treating Eimeria tenella infection in broilers.Broiers,at the age of 14 d,were orally infected with sporulated Eimeria tenella oocysts,and then,eugenol essential oil was added to chicken feed at three different dosages(0.1,0.2 or 0.4 g/kg).The anticoccidial effects of eugenol essential oil were assessed using the anticoccidial index(ACI).As a result,eugenol exhibited a moderate anticoccidial effect,with an ACI of 167.37 at 0.2 g/kg.After eugenol treatment,the expression of occludin in the epithelial cells of the chicken cecum was significantly greater(P<0.05)than that in the epithelial cells of the nontreated control(IC)group.The proportion of intestinal Lactobacillus_agilli increased.Eugenol therapy dramatically increased the activity of superoxide dismutase.After high-dose treatment,the expression of the proinflammatory factors IL-1βand IL-6 significantly decreased,while the expression of the cytokines IL-4 and IFN-γsignificantly increased.The safety of eugenol essential oil was evaluated at the 1,3 or 6 recommended doses.Overall,no significant differences were detected in the blood tests or serum biochemistry of the chickens between the treatment groups and the control group.As a result,eugenol essential oil can cure chicken coccidiosis by improving the intestinal microbial structure in the chicken cecum and decreasing the cecum's inflammatory reactions,thus strengthening immune function and eventually demonstrating anticoccidial properties.展开更多
基金supported by the Medical and Health Projects in Zhejiang Province(No.2022PY049)the Basic Scientific Research Project of Hangzhou Medical College(No.YS2021006)Key Discipline of Zhejiang Province in Public Health and Preventive Medicine(First Class,Category A),Hangzhou Medical College.
文摘Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 species of VOCswere simultaneously determined in surface soil samples collected from 63 chemical industrial parks(CIPs)across China.The results showed that the total VOC concentrations ranged from 7.15 to 1842 ng/g with a mean concentration of 326 ng/g(median:179 ng/g).Benzene homologs and halogenated hydrocarbons were identified as the dominant contaminant groups.Positive correlations between many VOC species indicated that these compounds probably originated from similar sources.Spatially,the hotspots of VOC pollution were located in eastern and southern China.Soils with higher clay content and a higher fraction of total organic carbon(TOC)content were significantly associated with higher soil VOC concentrations.Precipitation reduces the levels of highly water-soluble substances in surface soils.Both positive matrix factorization(PMF)and principal component analysis-multiple linear regression(PCA-MLR)identified a high proportion of industrial sources(PMF:59.2%and PCA-MLR:66.5%)and traffic emission sources(PMF:32.3%and PCA-MLR:33.5%).PMF,which had a higher R^(2) value(0.7892)than PCA-MLR(0.7683),was the preferred model for quantitative source analysis of soil VOCs.The health risk assessment indicated that the non-carcinogenic and carcinogenic risks of VOCs were at acceptable levels.Overall,this study provides valuable data on the occurrence of VOCs in soil from Chinese CIPs,which is essential for a comprehensive understanding of their environmental behavior.
基金Supported by Modern Agricultural Industrial Technology System Construction Project(CARS14-1-29)
文摘Volatile flavor components in foods are the key quality parameters. The researchers conducted in-depth research on sesame oil, peanut oil, rapeseed oil, sunflower oil, sesame paste and peanut butter, etc. However, there is no comprehensive summary about the flavor of roasted oilseeds and their products. The occurrence and the formation mechanisms of the main volatile flavor substances,and the impacts of processing factors are discussed in this review, which may provide references for further research on volatile flavor compounds, identification and evaluation of specific products and development of new products.
文摘[Objectives]To analyze the composition of volatile oils from mango leaves from different producing areas.[Methods]The volatile oils in mango leaves from different areas was extracted by steam distillation,and the GC-MS method combined with retention index and peak area normalization method was used for qualitative and quantitative analysis.[Results]The volatile oils of mango leaves in southern provinces contained high content of terpenes,such asα-gurjunene(18.39%-34.13%),(+)-viridiflorene(8.95%-16.30%)and(E)-β-ocimene(3.49%-7.63%).The volatile oils components of mango leaves were significantly different in different provinces,for example,mango leaves produced in Hainan Province contained a large amount ofβ-selinene(23.00%),but not in other provinces.[Conclusions]The origin had a great influence on the composition and contents of volatile oils in mango leaves.
基金supported by the National Environmental Protection Public Welfare projects(Nos.201409047 and 201109017)the “13th Five-Year Plan” National Key Research and Development Program of China(No.2016YFC0501108)+1 种基金the Fundamental Research Funds for the Central Universities(No.2016QH02)Beijing Natural Science Foundation(No.8152025)
文摘Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures（silty,clayey, and sandy soils） along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform（TCM） and trichloroethylene（TCE）. Mechanical soil aeration was effective for remediating VCHs（removal efficiency 〉 98%）. The volatilization process was described by an exponential kinetic function.In the early stage of treatment（0–7 hr）, rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.
文摘Leaf and stem essential oils of Lonchocarpus cyanescens Benth., (Fabaceae) were obtained by hydro-distillation, using all-glass apparatus adapted to British Pharmacopeia specifications with yields of 0.03% and 0.17% respectively. The oils were investigated by GC and GC-MS analyses. Results show seven compounds were responsible for 90.4% of leaf;eleven compounds responsible for 97.6% of stem volatile oils. Phytol (62.5%) and hexadecanoic acid (12.4%) dominate the leaf oil;octadecenoic (24.1%) and hexadecanoic acids (17.2%) are predominant in the stem oil. Phytochemical screening of stem, leaf, and root methanol extracts of Lonchocarpus cyanescens reveal presence of following seven classes of metabolites: saponin, tannin, steroid, terpenoid, cardiac glycosides, phlobatannins and flavonoids. Partitioning of methanol extract from dried leaf of it with ethylacetate gave fraction, which was chromatographed using gradient elution. TLC with high Rf was used in monitoring elution. Two white crystalline solids eluted at 5% and 10% ethylethanoate in hexane, were re-crystallized and characterized. They were subjected to Infra-Red spectra, mass spectrometry (ESI technique), 1H and 13C-NMR analyses, which confirmed they are triterpenoids. Above mentioned metabolites may be responsible for literature acclaimed bio-activities L. cyanescens display [anti-inflammatory, anti-arthritic, anti-microbial effects]. This paper presents details of above results which are new in literature.
基金Supported by Project of Department of Education of Sichuan Province(16ZB0205)Program of Southwest Medical University(2011-08)
文摘[Objectives] To study the effects of volatile oils of Sichuan Citrisarcodactylis fructus on proliferation and apoptosis of MCF-7human breast cancer cells.[Methods]CCK-8 method was used to measure the cell proliferation,the flow cytometry was used to measure changes in cell cycle,Western blot was used to detect p53 and cyclin D1 activity changes,TUNEL method was used to measure percentage of apoptotic cells,inverted phase contrast microscope and transmission electron microscope were used to observe morphology of MCF-7 cells treated with different concentrations.[Results]When the concentration was 5-50 μmol/L,the cell proliferation inhibition rate increased significantly(P <0. 05),G2/M phase decreased significantly( P < 0. 05),eventually disappeared completely,G1 phase significantly increased with time and concentration( P < 0. 05),finally reached 90. 0%; the activity of cyclin D1 significantly declined( P < 0. 05),while the activity of p53 had no significant change( P > 0. 05). The apoptotic rate of MCF-7 cells significantly increased with the extension of time( P < 0. 05). At6 h,12 h and 24 h of action time,the apoptotic rate of MCF-7 cells significantly increased with the increase in volatile oil concentration(P <0. 05). Morphological observation showed that the apoptosis of MCF-7 cells was obvious.[Conclusions]The volatile oils of Citrisarcodactylis fructus have obvious inhibition of proliferation of MCF-7 cells and function of inducing apoptosis,and the effects took on the dose and time dependent. 5-50 μmol/L volatile oil of Sichuan Citrisarcodactylis fructus can inhibit the proliferation of MCF-7 cells and induce the apoptosis of MCF-7 cells through inhibiting the cyclin D1.
基金financially supported by the National Science Foundation of China(No.81302733)the research project of Chinese Ministry of education(No.113036A)+3 种基金the Program for Jiangsu province Innovative Research Team,the Program for New Century Excellent Talents in University(No.NCET-13-1036)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Fundamental Research Funds for the Central Universities(No.JKZD2013004)the Open Project Program of State Key Laboratory of Natural Medicines,China Pharmaceutical University(Nos.SKLNMZZYQ 201303 and SKLNMKF201220)
文摘With a great difference in therapeutic effects of Mahuang(MH, the stems of Ephedra sinica) and Mahuanggen(MHG, the roots of Ephedra sinica), chemical differences between MH and MHG should be investigated. In the present study, gas chromatography-mass spectrometry(GC-MS)-based plant metabolomics was employed to compare volatile oil profiles of MH and MHG. The antioxidant activities of volatile oils from MH and MHG were also compared. 32 differential chemical markers were identified according to the variable importance in the projection(VIP) value of orthogonal partial least squares discriminant analysis(OPLS-DA) and P value of Mann-Whitney test. Among them, chemical markers of tetramethylpyrazine(TMP) and α-terpineol were quantified. Their contents were much higher in most MH samples compared with MHG. The antioxidant assay demonstrated that MH had significantly higher free radical-scavenging activity than MHG. Although MH and MHG derived from the same medicinal plant, there was much difference in their volatile oil profiles. MH samples had significantly higher content of two reported pharmacologically important chemical markers of TMP and α-terpineol, which may account for their different antioxidant activities.
文摘Objective:To determine the chemical composition of essential oils and lipid constituents of Ballola andreuzziana(B.andreuzziana),Teucrium zanonii(T.zanonii) and Verbena tenuisecta(V. tenuisecta) growing in Libya,and to test the antibacterial activity of different extracts of Teucrium zanonii.Methods:The volatile oils of all plants were extracted by hydrodistillation method and analyzed by GC/MS method.The lipid constituents of plants were obtained by extraction with petroleum ether and fractionated into fatty alcohols,fatty acids and unsapoinfiable matters. Antibacterial activity of T.zanonii extracts and antioxidant activity of different extracts of T. zanonii were also studied.Results:The volate oil of B.andreuzziana was found to consists of 20 compounds in which caryophyllin is the main one(63.1%),the volatile oil of T.zanonii consists of 74 compounds in which germacrene-D was the main compound,while the volatile oil of V. tenuisecta consists of 13 compounds with l-octen-3- ol as a major constituent(52.87%).The study of antimicrobial activity of different extracts of V.tenuisecta showed that,both methanol and butanol extracts exhibited the highest activity against Mycobacterium phlei(M.pblei) and Candida albicans(C.albicans) respectively,while petroleum ether,fatty alcohols and unsaponifiable fractions had no antimicrobial activity against all the tested microorganisms. Investigation of the antioxidant activity of different extracts of T.zanonii using DPPH method proved that,the ethyl acetate and butanol fractions showed the highest activity where the inhibition percentage(1%) are 93.6 and 92.1 respectively.Conclusions:This is the first report about the volatile oils of these plants where T.zanonii have the highest content and the highest number of the identified compounds.The study of antioxidant T.zanonii extracts proved that,the ethyl acetate,butanol and aqueous extracts have the highest antioxidant activity.Methanol and butanol extracts of V.tenuisecta exhibited the highest activity against M.phlei and C.albicans respectively.
文摘A comparison study has been performed in hempseed oils (HSO) extracted from different cultivars in Bama region. Squeezing properties, chemical compositions, thermal stability and flavor profile of pressed HSO were determined in this study. Results indicated that there were no significant differences in crude fat, protein, fiber of different hempseeds and fatty acid composition in HSOs. Hempseeds with small size and dark-colored peel have lower squeezing oil yield than big ones. Average content of total phytosterol, tocopherol and phenol in HSO from small seeds were 872.0 mg/100 g, 124.1 mg/100 g and 15.5 mg SA/100 g respectively. Thermal oxidation by differential scanning calorimetry (DSC) revealed three step oxidation of HSO with mean onset and oxidation temperature at 124oC and 135-315oC. Oxidation temperature of HSO from small seeds was higher than that from big seeds (big size and light-colored peel). Main volatile ingredients in HSO contained 11 kinds of monoterpene and 7 kinds of sesquiterpene. Volatile terpene content in HSO from small seeds was nearly 30% higher than that of big seeds. Quality of HSO with different peel feature has significant difference in squeezing yield, thermal stability and volatile flavors. This work may be useful to produce high quality hempseed oils through quality evaluation.
文摘Rosa x alba is cultivated almost exclusively for the production of aromatic water and fruits widely used as ingredients in some traditional food preparations sold commercially.Results of the proximate and elemental analyses revealed that flowers exhibited higher moisture content while the dry matter content was higher in leaves.Total fat and ash was higher in fruits when compared with leaves and flowers.All studied organs were found to be rich in essential mineral such as K,Ca,P and Mg.Qualitative and quantitative analysis of the volatile oils revealed different composition patterns between organs.Linalool and geraniol were found as major constituents of the leaf oil whereas 2-phenethyl alcohol and eugenol were the major constituents of the floral oil.In contrast,fruits showed very distinct composition and alkanes/alkenes were found to have the major contribution.The present composition could justify the traditional use of Rosa x alba which could be considered as a potential source of essential minerals and volatile constituents.
文摘Azadirachta indica A. Juss (neem, family Meliaceae) is a reputable medicinal plant. Various parts of the plant are used as a remedy against different ailments, as a natural pesticide, as raw material in the cosmetic industry, and for marking other commodities. The seed oil is a major product of the plant and its quality depends on the seed quality and extraction methods employed. In this study, the chemical profile of NIPRDNEEM oil is compared with that of other brands of neem seed oils by using gas chromatography-mass spectrometry (GC-MS) and chemometrics. The fatty acid identified in NIPRDNEEM oil were: oleic acid (34.09%), stearic acid (11.4%), linoleic acid (15.94%), palmitic acid (23.4%), arachidic acid (0.73%), and the other compounds were: 1-Monolinoleoylglycerol trimethylsilyl ether (0.95%) and farnesyl alcohol (13.20%). The branded oils were composed predominantly of oleic acid (13.50% - 26.76%), palmitic acid (6.88% - 11.99%), linoleic acid (7.32% - 11.17%), stearic acid (4.29% - 13.08%), and arachidic acid (0.53% - 1.27%). The unbranded oil contained oleic acid (30.04%), stearic acid (14.91%), linoleic acid (14.62%), palmitic acid (12.34%), and arachidic acid (0.93%). Stigmasterol, stigmasterol acetate, and sitosterol were the sterols identified in the oils. Characterization of the fatty acid profile of neem seed oil is vital for industrial and economic purposes. The fatty acids profile of the NIPRDNEEM oil and other neem seed oil were comparable. Both PCA plots and HCA dendrogram from the chemometric analysis shows three main grouping of all samples. While NIPRDNEEM and the local neem oil were grouped, suggesting a high degree of resemblance of both samples.
基金Supported by Undergraduate Innovation and Entrepreneurship Project of Department of Education of Guangxi Zhuang Autonomous Region(No:201813643063).
文摘[Objectives]This study was conducted to compare and analyze the chemical constituents of the volatile oils of the Yao medicine Thunbergia grandiflora from different habitats.[Methods]A quartz capillary column DB-1MS,an EI ion source and a quadrupole mass analyzer were used for analysis.The chromatographic and mass spectrum information obtained was automatically retrieved and analyzed by data processing system and its memory spectrum library(Nist.08).The relative content of each chemical component in the volatile oil was determined by the peak area normalization method.[Results]Forty nine chromatographic peaks were isolated from the sample produced in Shitun,Bailongtan Town,Mashan County,and 24 chemical constituents were identified,accounting for 88.78% of the total volatile oil.Forty nine chromatographic peaks were isolated from the sample produced in Hongdu Village,Chengjiang Town,Duan County,and 30 chemical constituents were identified,accounting for 88.38% of the total volatile oil.Forty eight chromatographic peaks were isolated from the sample produced in Longwan Township,Du'an County,and 25 chemical constituents were identified,accounting for 80.01% of the total volatile oil.Nine chemical constituents were common to the volatile oils of the samples from the three habitats.[Conclusions]It could be seen that the main components of volatile oils from T.grandiflora produced in different areas are different.
文摘Six types of termites＇ baits （cartoon, rough tissues, soft toilet tissues, acacia wood, saw dust of building wood and sackcloth） were elicited variable degree of attraction toward Anacanthotermes ochaceus, where the best one was cardboard, followed by soft and rough toilet tissue at mono-choice and multiple-choice tests. Chemical analysis showed that there were variations in the chemical constituents （lignin, cellulose, N, H and C） of the six baits studied. On the other hand, olfactory reactions of harvester termites toward eight volatile oils （four natural medical plants and four commercial terpines） were repellent, but the most repellent one was cineol and the least one was clove oil. The most tested oils were caused inhibition in feeding, except cedar wood. The most toxic oils were cineol followed by thymol.
文摘The rising risk of synthetic preservatives as antimicrobial agent has increased,leading to potential allergic reactions,intoxications,cancer,and other degenerative diseases.As a result,essential oils(EOs),recognized as natural antimicrobial agents due to their extensive antibacterial properties,have gained attention.However,their industrial applicability is hindered by challenges such as volatility,poor water solubility,oxidation potential,photodegradation,and thermal instability.Nano-encapsulation has emerged as a transformative solution for delivering essential oils,enhancing their stability,bioavailability,and targeted administration.This review explores the use of nano-encapsulated essential oils in combating bacteria,focusing on their mechanisms of action and potential advancements for the food preservation industry.Various nano-encapsulation methods,including liposomes,nanoemulsions,polymeric nanoparticles,and biopolymers like chitosan and alginate,have shown promise in overcoming the limitations associated with EOs.
基金supported by the National Natural Science Foundation of China(31901354)the Innovation Foundation of the Beijing Academy of Agriculture and Forestry Sciences(KJCX20200112)the Science and Technology Innovation Capacity Construction Project of the Beijing Academy of Agriculture and Forestry Sciences(KJCX20200113-30 and KJCX20200302-03).
文摘Chrysanthemum and Opisthopappus are genera that include perennial herbaceous floral species,including excellent varieties with strong fragrances resulting from long-term artificial selection.Thus,they are ornamentally and economically important flower resources.In this study,a water distillation method was used to extract essential oils from the inflorescences of Chrysanthemum and Opisthopappus wild resources and hybrid progeny with high essential oil contents(Chrysanthemum morifolium'xiangjin',C.morifolium'xiangyun',C.morifolium'xinjiboju',Opisthopappus taihangensis,Opisthopappus longilobus,Chrysanthemum lavandulifolium,and C.morifolium'minghuangju').The essential oil extraction rates were as follows:1.17‰,2‰,1.67‰,2.17‰,0.43‰,1‰,and 1.17‰.On the basis of HS-SPME-GC-MS(Headspace solid phase microextraction-gas chromatography-mass spectrometry),225 volatile compounds were detected in the seven analyzed essential oil samples.Each essential oil had a relative volatile component content exceeding 0.3.The three most abundant compounds were olefins(46 types),alcohols(34 types),and esters(18 types).The volatile components with relatively high contents included thymol,D-camphor,pinene,eucalyptol,2-terpineol,terpineol,trans-caryophyllene,andβ-elemene.These volatile compounds have strong biological activities and are useful components of medicines and daily-use products.An evaluation of their antibacterial effects demonstrated that the essential oils of C.'xiangjin',C.'xiangyun',C.'xinjiboju',O.taihangensis,O.longilobus,and C.'minghuangju'inhibited the growth of Escherichia coli.The C.lavandulifolium essential oil inhibited the growth of Pectobacterium carotovorum.The results of this study will provide researchers with an important theoretical basis for the development and application of Chrysanthemum and Opisthopappus essential oils.
基金supported by the National Natural Science Foundation of China (NSFC)Projects (Nos.42205105,42121004,and 42077190)the Science and Technology Project of Shaoguan (No.210811164532141)+3 种基金the National Key R&D Program of China (2022YFC3700604)the Science and Technology Program of Guangzhou City (No.202201010400)the Fundamental Research Funds for the Central Universities (No.21622319)the Research Center of Low Carbon Economy for Guangzhou Region (No.22JNZS50).
文摘Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients(600-1690ma.s.l.)in the Nanling Mountains of southern China.Composition characteristics as well as seasonal and altitudinal variations were analyzed.Standardized emission rates and canopyscale emission factors were then calculated.Results showed that BVOCs emission intensities in the wet season were generally higher than those in the dry season.Monoterpenes were the dominant BVOCs emitted from most broad-leaved trees,accounting for over 70%of the total.Schima superba,Yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation potentials.The localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols fromNature(MEGAN),while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the model.Our results can be used to update the current BVOCs emission inventory in MEGAN,thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China.
文摘The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the optimal way to deploy injection-production well networks are critical issues that must be urgently addressed for efficient oilfield development.Experimental research on the mixed-phase displacement mechanism through gas injection into indoor formation fluids was conducted to guide the efficient development of gas injection in oil fields.We established a model of dual-medium reservoir composition and researched the deployment strategy for a three-dimensional well network for gas injection development.The coupling relationship between key influencing factors of the well network and fracture development was also quantitatively analyzed.The results show that the solubility of the associated gas and strong volatile oil system injected into the BZ oilfield is high.This high solubility demonstrates a mixed-phase displacement mechanism involving intermediate hydrocarbons,dissolution and condensation of medium components,and coexistence of extraction processes.Injecting gas and crude oil can achieve a favorable mixing effect when the local formation pressure is greater than 35.79 MPa.Associated gas reinjection is recommended to supplement energy for developing the highly volatile oil reservoirs in the fractured buried hills of the BZ oilfield.This recommendation involves fully utilizing the structural position and gravity-assisted oil displacement mechanism to deploy an injection-production well network.Gas injection points should be constructed at the top of high areas,and oil production points should be placed at the middle and lower parts of low areas.This approach forms a spatial threedimensional well network.By adopting high inclination well development,the oil production well forms a 45°angle with the fracture direction,which increases the drainage area and enhances single-well production capacity.The optimal injection-production well spacing along the fracture direction is approximately 1000 m,while the reasonable well spacing in the vertical fracture direction is approximately 800 m.The research results were applied to the development practice of the buried hills in the BZ oilfield,which achieved favorable development results.These outcomes provide a valuable reference for the formulation of development plans and efficient gas injection development in similar oil and gas fields in buried hills.
基金supported by the National Key Research and Development Program of China(2021YFD1400700)the Natural Science Foundation of Anhui Province,China(2308085MC89)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(ASTIP)。
文摘The fall armyworm(Spodoptera frugiperda)is an invasive species and a destructive pest of maize,which significantly impacts native species and communities via complex mechanisms like competition for resources.However,the interaction between S.frugiperda and local pests remains unclear.In this study,we determined that Oriental armyworm(Mythimna separata)females with different mating status displayed different approach-avoidance behaviors towards maize which was infested by S.frugiperda larvae.The virgin M.separata females were repelled,while the mated females were attracted by the S.frugiperda-infested maize.To further understand the olfactory mechanism of this phenomenon,seven volatiles induced by S.frugiperda in maize were characterized by gas chromatography and mass spectrometry(GC-MS),including trans-2-hexenal,linalool,trans-β-farnesene,cis-3-hexenyl acetate,β-caryophyllene,trans-α-bergamotene,and isopentyl acetate.Additionally,electrophysiological and behavioral assays of the seven compounds were performed using both virgin and mated females of M.separata.We determined that virgin and mated females displayed different responses to the herbivore-induced plant volatile(HIPV).Trans-β-farnesene was the core compound for repelling virgin females,and trans-2-hexenal was the key attractant for oviposition in mated female M.separata individuals.These findings help our comprehension of the relationships between maize pests and offer new possibilities for controlling them by olfactory-based strategies.
基金supported by the Research and Development of Ecological Control Mechanisms and Application Techniques for Forest Pest and Disease in the North and South Mountains of Lhasa(No.XZ202301ZY0019N)Construction and Comprehensive Service Cap ability Enhancement of Plateau Characteristic Agricultural and Animal Husbandry Science and Technology Small Courtyard(XK202403)。
文摘This study examined the EAG(Electroantennogram)responses of Stilpnotia candida to a mix of host plant volatiles and to provide a foundation for the development of plant-derived attractants.During the peak period of adult eclosion,gas chromatography–mass spectrometry analyzed and identified the volatiles emitted by Populus×beijingensis found in Xizang.Based on the preliminary EAG experiments and the GC‒MS results,a blending scheme was developed.EAG and Y-tube-olfactometry were employed to measure the electrophysiological and behavioural responses of unmated males and females 24 h after eclosion 10 blends of volatiles derived from five host plants.The GC–MS analysis revealed 22 volatile compounds from Populus×beijingensis leaves,composed of esters,hydrocarbons,terpenoids,alcohols,phenols,and ether.The results indicated that all 10 blending schemes produced EAG responses in mature S.candida.The concentration thresholds were between 1 and 10μg·μL^(-1),above the optimal concentration,and a corresponding decrease in EAG was observed.According to intergroup comparisons,mature S.candida had more pronounced EAG responses.Under different concentrations,there were significant differences in the EAG from male and female S.candida to each blending scheme.Behavioural response tests indicated that schemes 2,7,and 8 exhibited significantly greater attractiveness to adult S.candida.The combined results from the EAG and behavioral response experiments demonstrated that unmated male and female adult S.candida have varying degrees of sensitivity to the volatile compounds from the 10 blending schemes specific to Xizangan Populus×beijingensis.Schemes 2,7,and 8 showed robust EAG responses and attractive behavioural responses to both male and female adult S.candida.
基金supported by the National Key Research and Development Program(2016YFD0501303).
文摘The development of alternative therapies to treat chicken coccidiosis has become a hot topic because of the widespread use of conventional medicines.This study aimed to investigate the effectiveness of eugenol in treating Eimeria tenella infection in broilers.Broiers,at the age of 14 d,were orally infected with sporulated Eimeria tenella oocysts,and then,eugenol essential oil was added to chicken feed at three different dosages(0.1,0.2 or 0.4 g/kg).The anticoccidial effects of eugenol essential oil were assessed using the anticoccidial index(ACI).As a result,eugenol exhibited a moderate anticoccidial effect,with an ACI of 167.37 at 0.2 g/kg.After eugenol treatment,the expression of occludin in the epithelial cells of the chicken cecum was significantly greater(P<0.05)than that in the epithelial cells of the nontreated control(IC)group.The proportion of intestinal Lactobacillus_agilli increased.Eugenol therapy dramatically increased the activity of superoxide dismutase.After high-dose treatment,the expression of the proinflammatory factors IL-1βand IL-6 significantly decreased,while the expression of the cytokines IL-4 and IFN-γsignificantly increased.The safety of eugenol essential oil was evaluated at the 1,3 or 6 recommended doses.Overall,no significant differences were detected in the blood tests or serum biochemistry of the chickens between the treatment groups and the control group.As a result,eugenol essential oil can cure chicken coccidiosis by improving the intestinal microbial structure in the chicken cecum and decreasing the cecum's inflammatory reactions,thus strengthening immune function and eventually demonstrating anticoccidial properties.
