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
A laboratory study was conducted to investigate volatile organic compound（VOC） emissions from agricultural soil amended with wheat straw and their associations with bacterial communities for a period of 66 days unde...A laboratory study was conducted to investigate volatile organic compound（VOC） emissions from agricultural soil amended with wheat straw and their associations with bacterial communities for a period of 66 days under non-flooded and flooded conditions. The results indicated that ethene, propene, ethanol, i-propanol, 2-butanol, acetaldehyde, acetone,2-butanone, 2-pentanone and acetophenone were the 10 most abundant VOCs, making up over 90% of the total VOCs released under the two water conditions. The mean emission of total VOCs from the amended soils under the non-flooded condition（5924 ng C/（kg·hr）） was significantly higher than that under the flooded condition（2211 ng C/（kg·hr））. One ＂peak emission window＂ appeared at days 0–44 or 4–44, and over 95% of the VOC emissions occurred during the first month under the two water conditions. Bacterial community analysis using denaturing gradient gel electrophoresis（DGGE） showed that a relative increase of Actinobacteria, Bacteroidetes, Firmicutes and γ-Proteobacteria but a relative decrease of Acidobacteria with time were observed after straw amendments under the two water conditions. Cluster analysis revealed that the soil bacterial communities changed greatly with incubation time, which was in line with the variation of the VOC emissions over the experimental period. Most of the above top 10 VOCs correlated positively with the predominant bacterial species of Bacteroidetes, Firmicutes and Verrucomicrobia but correlated negatively with the dominant bacterial species of Actinobacteria under the two water conditions. These results suggested that bacterial communities might play an important role in VOC emissions from straw-amended agricultural soils.展开更多
Edible oils-rapeseed oil, soybean oil and peanut oil are heated in air at 270-280 ℃respectively. The volatile condensates are collected and analyzed by means of GC/MS. Eithercrotonaldehyde or 2-methylacrolein is foun...Edible oils-rapeseed oil, soybean oil and peanut oil are heated in air at 270-280 ℃respectively. The volatile condensates are collected and analyzed by means of GC/MS. Eithercrotonaldehyde or 2-methylacrolein is found respectively in the condensates of rapeseed oil andsoybean oil. Neither crotonaldehyde nor 2-methylacrolein is found in the condensates of peanut oil.Mechanism of formation of crotonaldehyde is discussed.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
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
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
[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
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
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
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
Analysis of Volatile Organic Compounds (VOCs) in crude coconut and petroleum oils from Nigeria is reported. Using head-space gas chromatography with a flame ionization detector and mass spectrometer, 8 VOCs were found...Analysis of Volatile Organic Compounds (VOCs) in crude coconut and petroleum oils from Nigeria is reported. Using head-space gas chromatography with a flame ionization detector and mass spectrometer, 8 VOCs were found in crude coconut oil and 29 VOCs were identified in crude petroleum oil. Crude coconut oil contained two aromatic, two nitrogenated, and four oxygenated compounds. Alkane, alkene, alkyne, halogenated, and sulfur compounds were absent in crude coconut oil but not in crude petroleum oil. The same observation held true for naphthalene. Conversely, benzofuran was absent in crude petroleum oil but was present in crude coconut oil at a concentration of 1.38 part-per-billion (ppb). The most concentrated VOC in crude coconut oil was dodecanoic acid at 9.98 ppb and that of crude petroleum oil was toluene at 12.61 ppb. Total VOC concentrations in crude coconut and petroleum oils are 20.49 and 87.46 ppb, respectively. These results are helpful in characterizing the chemical signature of Nigerian crude coconut oil for potential forensics use or in biofuel research.展开更多
Edible oils derived from aquatic products are rich in lipids beneficial to human health.However,the volatile flavor characteristics of flesh oil and liver oil from Doederleinia berycoides remain unclear.In this study,...Edible oils derived from aquatic products are rich in lipids beneficial to human health.However,the volatile flavor characteristics of flesh oil and liver oil from Doederleinia berycoides remain unclear.In this study,flesh oil and liver oil were extracted from Doederleinia berycoides,revealing different fatty acid compositions and contents.Lipidomics analysis identified a total of 124 differential lipids between the flesh oil and liver oil,including 42 glycerophospholipids(GPs),33 glycerolipids(GLs),23 free fatty acids(FAs),13 sphingolipids(SPs),10 sterols(STs),and 3 prenol lipids(PRs).Analysis using HS-GC-IMS identified 12 key volatile compounds that significantly contributed to the distinct volatile flavors of the flesh and liver oils.The volatile flavors originated from these volatile compounds,which had different Relative Odor Activity Values(ROAVs).Further results from HSSPME-GC-MS showed that the volatile flavors of the flesh oil and liver oil were respectively attributed to 64 and 35 volatile compounds,each with unique key volatile compounds exhibiting different ROAVs.There were significant positive or negative correlations between 18 key differential lipids and 24 volatile compounds in both flesh oil and liver oil.Therefore,the complex lipid profiles are responsible for the unique volatile flavors of flesh oil and liver oil,and the differential lipids play a central role in their volatile flavor formation.These findings provide a foundation for understanding the volatile flavor differences in fish oils and hold promise for further exploration of the molecular mechanisms underlying oil volatile flavors.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
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ...Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.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financially supported by the Natural Science Foundation of China(Nos.41025012,41103067,41571130031 and 41273095)
文摘A laboratory study was conducted to investigate volatile organic compound（VOC） emissions from agricultural soil amended with wheat straw and their associations with bacterial communities for a period of 66 days under non-flooded and flooded conditions. The results indicated that ethene, propene, ethanol, i-propanol, 2-butanol, acetaldehyde, acetone,2-butanone, 2-pentanone and acetophenone were the 10 most abundant VOCs, making up over 90% of the total VOCs released under the two water conditions. The mean emission of total VOCs from the amended soils under the non-flooded condition（5924 ng C/（kg·hr）） was significantly higher than that under the flooded condition（2211 ng C/（kg·hr））. One ＂peak emission window＂ appeared at days 0–44 or 4–44, and over 95% of the VOC emissions occurred during the first month under the two water conditions. Bacterial community analysis using denaturing gradient gel electrophoresis（DGGE） showed that a relative increase of Actinobacteria, Bacteroidetes, Firmicutes and γ-Proteobacteria but a relative decrease of Acidobacteria with time were observed after straw amendments under the two water conditions. Cluster analysis revealed that the soil bacterial communities changed greatly with incubation time, which was in line with the variation of the VOC emissions over the experimental period. Most of the above top 10 VOCs correlated positively with the predominant bacterial species of Bacteroidetes, Firmicutes and Verrucomicrobia but correlated negatively with the dominant bacterial species of Actinobacteria under the two water conditions. These results suggested that bacterial communities might play an important role in VOC emissions from straw-amended agricultural soils.
文摘Edible oils-rapeseed oil, soybean oil and peanut oil are heated in air at 270-280 ℃respectively. The volatile condensates are collected and analyzed by means of GC/MS. Eithercrotonaldehyde or 2-methylacrolein is found respectively in the condensates of rapeseed oil andsoybean oil. Neither crotonaldehyde nor 2-methylacrolein is found in the condensates of peanut oil.Mechanism of formation of crotonaldehyde is discussed.
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.
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.
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 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.
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.
文摘Analysis of Volatile Organic Compounds (VOCs) in crude coconut and petroleum oils from Nigeria is reported. Using head-space gas chromatography with a flame ionization detector and mass spectrometer, 8 VOCs were found in crude coconut oil and 29 VOCs were identified in crude petroleum oil. Crude coconut oil contained two aromatic, two nitrogenated, and four oxygenated compounds. Alkane, alkene, alkyne, halogenated, and sulfur compounds were absent in crude coconut oil but not in crude petroleum oil. The same observation held true for naphthalene. Conversely, benzofuran was absent in crude petroleum oil but was present in crude coconut oil at a concentration of 1.38 part-per-billion (ppb). The most concentrated VOC in crude coconut oil was dodecanoic acid at 9.98 ppb and that of crude petroleum oil was toluene at 12.61 ppb. Total VOC concentrations in crude coconut and petroleum oils are 20.49 and 87.46 ppb, respectively. These results are helpful in characterizing the chemical signature of Nigerian crude coconut oil for potential forensics use or in biofuel research.
基金supported by the R&D Projects in Key Areas of Guangdong Province(2023B0202080003)the National Natural Science Foundation of China(32472272,32302135,32072291)+1 种基金“Pioneer”and“Leading Goose”R&D Program of Zhejiang(2023C02006)Youth S&T Talent Support Programme of Guangdong Provincial Association for Science and Technology(SKXRC202401)。
文摘Edible oils derived from aquatic products are rich in lipids beneficial to human health.However,the volatile flavor characteristics of flesh oil and liver oil from Doederleinia berycoides remain unclear.In this study,flesh oil and liver oil were extracted from Doederleinia berycoides,revealing different fatty acid compositions and contents.Lipidomics analysis identified a total of 124 differential lipids between the flesh oil and liver oil,including 42 glycerophospholipids(GPs),33 glycerolipids(GLs),23 free fatty acids(FAs),13 sphingolipids(SPs),10 sterols(STs),and 3 prenol lipids(PRs).Analysis using HS-GC-IMS identified 12 key volatile compounds that significantly contributed to the distinct volatile flavors of the flesh and liver oils.The volatile flavors originated from these volatile compounds,which had different Relative Odor Activity Values(ROAVs).Further results from HSSPME-GC-MS showed that the volatile flavors of the flesh oil and liver oil were respectively attributed to 64 and 35 volatile compounds,each with unique key volatile compounds exhibiting different ROAVs.There were significant positive or negative correlations between 18 key differential lipids and 24 volatile compounds in both flesh oil and liver oil.Therefore,the complex lipid profiles are responsible for the unique volatile flavors of flesh oil and liver oil,and the differential lipids play a central role in their volatile flavor formation.These findings provide a foundation for understanding the volatile flavor differences in fish oils and hold promise for further exploration of the molecular mechanisms underlying oil volatile flavors.
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 Hong Kong Environment Protection Department(Quotation Ref.18-06532)Hong Kong Innovation and Technology Fund(ITS/193/20FP)Hong Kong Research Grants Council(No.26304921).
文摘Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.
