芫荽茎叶精油的消除DPPH自由基作用

用GC-MS对超声波法提取的芫荽茎叶精油成分进行了分析,检测出154个成分,解析出70种物质,占精油93．643％,含量最多的是酯类化合物47．569％,其次为饱和与非饱和烃类化合物19．897％,醛类化合物和醇类化合物含量分别为13．406％,12．595％。探讨了精油对DPPH的清除作用,结果显示,用超声波萃取法获得的精油对DPPH自由基（1,1-diphenyl-2-picrylhydrazyl）具有一定的消除作用,最高消除率62．9％,水蒸汽蒸馏法获得的芫荽茎叶精油的DPPH自由基清除率最大为84．2％。     

Comparative Analysis of Antioxidant Activities of Fourteen Mentha Essential Oils and Their Components

The essential oils of 14 species and hybrids, respectively, of the genus Mentha were examined for their antioxidant capacity in the ABTS (2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid)) assay and in a lipid‐peroxidation (LPO) assay. The ABTS^.+‐scavenging capacity of pure essential‐oil components and mixtures of them was also tested. In both assays, Mentha×dumetorum (classification not fully confirmed), Mentha suaveolens, and Mentha×villosa (classification not fully confirmed) showed the highest antioxidant capacity, which was ascribed to the components germacrene D, piperitone oxide, and piperitenone oxide. The high antioxidant activity in the LPO assay of the two hybrids Mentha×gracilis and, to a lower degree, of Mentha×dalmatica (classification not fully confirmed) was ascribed to their high contents of cis‐ocimene and β‐caryophyllene. Of the pure components tested (germacrene D, piperitone oxide, and piperitenone oxide were not tested, as not commercially available), only cis‐ocimene showed a distinct antioxidant effect, whereas dihydrocarvone and linalool had pro‐oxidant effects in the ABTS assay.     

Antioxidant Effect of Peptide in Combination with Sugar on Autoxidation of Edible Oils

The antioxidant effect of various combinations of peptide and sugar was investigated by an oven-storage test using lard as substrate. High antioxidant activity was resulted from combining a peptides with branched-chain amino acids and xylose. For this effect, the presence of a branched-chain amino acid was more favorable at the N-terminal position of the peptide than at the C-terminal position. A synergistic effect was observable with xylose at a molar ratio of xylose-peptide of 0.05. The leucylglycine-xylose composition was also effective for preventing oxidation in selected vegetable oils.     

川芎精油和多糖的同步提取及其抗氧化活性分析

采用响应面优化法对超声波辅助法同步提取川芎精油(LCEO)和多糖(LCP)工艺条件进行优化,以总还原力和DPPH·清除率为指标评价LCEO和LCP的抗氧化活性.结果表明,川芎精油和多糖提取的最佳工艺条件为:液料比16mL/g,超声时间17 min,提取时间4.3 h,在此条件下,精油提取率为1.35％,多糖提取率为2....     

桂丁、草蔻挥发油抗氧化性研究

采用脂质过氧化方法和DPPH方法分别检测了2种植物挥发油抗脂质过氧化活性和清除自由基活性.且通过和阳性对照Vitamin E和Vitamin C的比较发现2种植物挥发油均有不同程度的抗脂质过氧化活性和清除自由基的活性.草蔻的抗脂质过氧化活性在低浓度下抑制率很高,在浓度为0.097～1.2 mg/mL之间其抗氧化能力强于桂丁.用IC50和EC50来评价抗脂质过氧化能力和清除自由基活性,则草蔻挥发油的抗脂质过氧化活性最强,且强于阳性对照Vitamin C,即草蔻的IC50为0.099 mg/mL.对于草蔻和桂丁的清除自由基的能力是相似的,EC50分别为4.50和4.46 mg/mL.     

蜂胶挥发油抗氧化性能及其成分研究

采用超临界CO2萃取和冷冻分离得到蜂胶挥发油,用化学发光法测定蜂胶挥发油对羟自由基和超氧阴离子自由基的清除性能,并用色质联用法分析其化学组成.实验结果表明,蜂胶挥发油能有效抑制羟自由基和超氧阴离子自由基诱导的化学发光,其IC50分别约为1.3和0.75 mg/mL.通过GC-MS分析,鉴定出51种化合物.     

Antimicrobial,Antioxidant, and Anti-Inflammatory Activities of Essential Oils from Five Selected Herbs

Eucalyptus bridgesiana, Cymbopogon martinii, Thymus vulgaris, Lindernia anagallis, and Pelargonium fragrans are five species of herbs used in Asia. Their essential oils were analyzed by GC-MS, and a total of 36 components were detected. The results of our study indicated that, except for the essential oil of P. fragrans, all of the essential oils demonstrated obvious antimicrobial activity against a broad range of microorganisms. The C. martinii essential oil, which is rich in geraniol, was the most effective antimicrobial additive. All of the essential oils demonstrated antioxidant activities on 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay, β-carotene/linoleic acid assay, and nitric oxide radical scavenging assay. Furthermore, the T. vulgaris essential oil, which possesses plentiful thymol, exhibited the highest antioxidant activity. For P. acnes-induced secretion of pro-inflammatory cytokines, the essential oils of P. aeruginosa, C. martinii, and T. vulgaris reduced the TNF-α, IL-1β, and IL-8 secretion levels of THP-1 cells.     

Biomolecular Characterization of Wild Sicilian Oregano: Phytochemical Screening of Essential Oils and Extracts,and Evaluation of Their Antioxidant Activities

An extensive survey of wild Sicilian oregano was made. A total of 57 samples were collected from various sites, followed by taxonomic characterization from an agronomic perspective. Based on morphological and production characteristics obtained from the 57 samples, cluster analysis was used to divide the samples into homogeneous groups, to identify the best biotypes. All samples were analyzed for their phytochemical content, applying a cascade‐extraction protocol and hydrodistillation, to obtain the non volatile components and the essential oils, respectively. The extracts contained thirteen polyphenol derivatives, i.e., four flavanones, seven flavones, and two organic acids. Their qualitative and quantitative characterization was carried out by LC/MS analyses. The essential oils were characterized using a combination of GC‐FID and GC/MS analyses; a total of 81 components were identified. The major components of the oils were thymol, p‐cymene, and γ‐terpinene. Cluster analysis was carried out on both phytochemical profiles and resulted in the division of the oregano samples into different chemical groups. The antioxidant activity of the essential oils and extracts was investigated by the Folin? Ciocalteau (FC) colorimetric assay, by UV radiation‐induced peroxidation in liposomal membranes (UV‐IP test), and by determining the O ‐scavenging activity.     

Influence of the Duration and Conditions of Storage on the Composition of the Essential Oil from Coriander Seeds

The composition of volatile components of the essential oil extracted from seeds of coriander (Coriandrum sativumL.) grown in different years in either Russia or Georgia was studied by capillary gas chromatography. Climatic conditions had a weaker effect on the essential oil composition than the region of growth. After one-year storage in the dark, minor changes were observed in the oil composition, and its organoleptic properties were virtually unchanged. However, the essential oil underwent significant chemical transformation of monoterpenes when stored in the light.     

香茅精油的抑菌和抗氧化活性研究

选用产自福建厦门的香茅(Cymbopogon nardus),测定香茅精油对白色粘性沙雷氏菌、红色粘性沙雷氏菌、大肠杆菌、金黄葡萄球菌、铜绿假单胞菌和紫色杆菌等6种菌的抑菌活性,并利用ABTS^.+自由基清除法以及超氧阴离子清除法研究香茅精油的抗氧化活性。结果表明,新鲜香茅精油的平均提取率为0.29,对6种供试菌种都有较高的抑制作用,其中对紫色杆菌的抑制活性最强,且香茅精油有极高的清除ABTS^.+自由基以及超氧阴离子自由基的能力,证明香茅精油具有广谱抑菌活性及强抗氧化活性。     

几种常用中草药抗氧化活性研究(英文)

当归、黄芪、银杏叶、益母草、野甘草是中国传统中药材,几千年来一直为中国人民所认可,在中国和世界都具有重要的科研和药用价值。本研究采用HO·清除及对肝微粒体和亚油酸脂质过氧化抑制的方法,测定五种草药精油和水煮提取物的抗氧化活性;采用Folin—Ciocalteu试剂法测定它们的总酚含量;用肝细胞体外培养法测定它们的细胞毒性并对它们的作用机制进行分析。结果发现五种草药提取物都具有一定的抗氧化活性,尤其是益母草、野甘草、银杏叶的水煮提取物活性较强,其抗氧化活性与总酚含量存在较好的线形关系。此外,本论文还为研究这些草药的一些抗病机制提供参考依据。     

Environmentally-Friendly Pesticidal Activities of Callicarpa and Karomia Essential Oils from Vietnam and Their Microemulsions

There is an ongoing interest to identify alternative pesticidal agents to avoid the chronic problems associated with synthetic pesticides. Essential oils have shown promise as botanical pest control agents. In the present study, the essential oils of four members of the Lamiaceae (Callicarpa candicans, C. erioclona, C. macrophylla, and Karomia fragrans; Vietnamese names: Nàng nàng, Tu châu lông mem, Tu châu lá to and Cà diện, respectively), obtained from wild populations in Vietnam, have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The essential oils were formulated into microemulsions and the essential oils and their microemulsions were screened for mosquito larvicidal activity against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and for molluscicidal activity against Pomacea canaliculata. Atractylone and (E)-caryophyllene dominated the volatiles of C. candicans (CCEO) and C. erioclona (CEEO), while the major component in C. macrophylla (CMEO) and K. fragrans (KFEO) was (E)-caryophyllene. The essential oils and microemulsions of both C. candicans and C. erioclona exhibited excellent larvicidal activity against all three mosquito species (Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus) with LC₅₀ values <10 μg/mL. Additionally, the larvicidal activity of the microemulsions were significantly improved compared with their free essential oils, especially for C. candicans and C. erioclona. All four essential oils and their microemulsions showed excellent molluscicidal activity with LC₅₀ <10 μg/mL. In most cases, the essential oils and microemulsions showed greater pesticidal activity against target organisms than the non-target freshwater fish, Oreochromis niloticus. The in silico studies on physicochemical and ADMET properties of the major components in the studied essential oils were also investigated and most of the compounds possessed a favorable ADMET profile. Computational modeling studies of the studied compounds demonstrated a favorable binding interaction with the mosquito odorant-binding protein target and support atractylone, β-selinene, and caryophyllene oxide as potential inhibitors. Based on the observed pesticidal activities of the essential oils and their microemulsions, the Callicarpa species and K. fragrans should be considered for potential cultivation and further exploration as botanical pesticidal agents.     

Antifungal Properties of Essential Oils Derived from the Genus Cymbopogon: A Systematic Review

Essential oils (EOs) are products of secondary metabolism with recognized organoleptic characteristics and biological properties. Recently, there has been a growing demand for EOs in the national and international market, mainly due to the recognition of their use as complementary medicine practices, and the increased use in the industries of pharmaceutics, cosmetics, well-being, veterinary and agroecology, boosting the productive sector. In this context, EOs from grasses of the Cymbopogon (Poaceae) are promising sources of bioactive compounds, due to their recognized biological properties, such as anti-inflammatory, antibacterial, antifungal, antidiabetic, repellent, and larvicide. Thus, the present study aims to carry out a review of the scientific literature of the main works related to the evaluation of the antifungal action of essential oils extracted from plants of the Cymbopogon genus, compiling the species that showed the best results and relating them to their main chemical constituents. This review covers the following species: C. citratus, C. flexuosus, C. winterianus, C. martinii, C. nardus, C. giganteus, C. schoenanthus, C. khasans, and C. proximus. Among them, C. citratus was the most assessed, being associated with the vast majority of studies (61.9 %), and it was also the species that showed the best results in terms of MIC.     

华南五种木兰科植物精油成分和抗氧化活性

对广东南岭自然保护区内野生的毛桃木莲（Manglietia moto）、乳源木莲（M．yuyanensis）、乐昌含笑（M．chapensis）、金叶含笑（M．foveolata）和深山含笑（M．maudiae）5种木兰科芳香植物精油进行了化学成分对比分析和抗氧化活性研究。化学成分鉴定采用气质联用技术,同时结合了保留指数比较法;精油抗氧化活性采用β-胡萝卜素漂白试验法。深山含笑芳香精油的主体成分以单萜烯为主,另外4种木兰科芳香精油所含成分均以倍半萜类为主。毛桃木莲和乳源木莲精油在成分构成上具有高度一致性,而且在主要成分上具有相似性,这可能表明它们具有非常近的植物亲缘关系。4种精油的抗脂质氧化半抑制浓度分别为6．6g／L（毛桃木莲精油）、9．8g／L（乳源木莲精油）、11．3g／L）金叶含笑精油）和12．2g／L（乐昌含笑精油）,在本试验条件下,未能测出深山含笑的半抑制浓度。     

杜虹花叶挥发油化学成分及抗氧化活性研究

采用气相色谱一质谱联用(GC-MS)对杜虹花(Callic arpa formosana Rolfe)叶挥发油的化学成分进行分析,并用DPPH法测定其抗氧化活性.结果表明,从杜虹花叶挥发油中鉴定出48种成分,占总挥发油的90.14%.其中(-)-斯巴醇(20.23%)、β-石竹烯(17.22%)、大根香叶烯(8.06%)和β-桉叶烯(5.52%)为其主要成分.此外,τ-榄香烯(4.18%)、马兜铃烯(3.78%)、异香橙烯氧化物(2.71%)及4-松油醇(2.50%)的含量也较高.抗氧化实验中,3种不同浓度的挥发油均对DPPH自由基有一定的清除能力,且有明显的量-效相关性.     

Antimutagenic and Antioxidant Potentials of Teucrium ramosissimum Essential Oil

The mutagenic and antimutagenic effects of the essential oil extracted from the aerial parts of Teucrium ramosissimum were evaluated by the bacterial reverse mutation assay in Salmonella typhimurium TA98, TA100, and TA1535, with and without exogenous metabolic activation (S9 fraction). The T. ramosissimum essential oil showed no mutagenic effect. In contrast, our results established that it possessed antimutagenic effects against sodium azide (SA), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and 4‐nitro‐o‐phenylenediamine (NOPD). The antioxidant capacity of the tested essential oil was evaluated using enzymatic, i.e., the xanthine/xanthine oxidase (X/XOD) assay, and nonenzymatic systems, i.e., the nitro‐blue tetrazolium (NBT)/riboflavin and the DPPH assays. A moderate free radical‐scavenging activity was observed towards DPPH^. and O$\rm{{_{2}^{{^\cdot} -}}}$ . In contrast, T. ramosissimum essential oil showed no effect for all the tested concentrations in the X/XOD assay.     

Effects of Essential Oils on Ruminal Microorganisms and Their Protein Metabolism

A commercial blend of essential oil (EO) compounds was added to a grass, maize silage, and concentrate diet fed to dairy cattle in order to determine their influence on protein metabolism by ruminal microorganisms. EO inhibited (P < 0.05) the rate of deamination of amino acids. Pure-culture studies indicated that the species most sensitive to EO were ammonia-hyperproducing bacteria and anaerobic fungi.     

Chemical Characterization of Euphorbia heterophylla L. Essential Oils and Their Antioxidant Activity and Allelopathic Potential on Cenchrus echinatus L.

The genus Euphorbia attracted the attention of many researchers worldwide from natural products, bioactivity, and ecological perspective. The essential oils (EOs) of Euphorbia heterophylla are poorly studied. Therefore, the present study aimed to provide a detailed profile of the E. heterophylla EOs as well as to determine their antioxidant and allelopathic activities. The EOs from aerial parts of E. heterophylla were extracted using hydrodistillation and analyzed via GC/MS. The antioxidant activity was determined based on scavenging of the free radical, 1,1‐diphenyl‐2‐picrylhydrazyl and H₂O₂. Various concentrations of the EOs were tested against the noxious weed, Cenchrus echinatus. Thirty‐five compounds were identified representing 100 % of the total mass. Four classes of components were characterized, among which terpenoids were the main components (88.70 %). Monoterpenes represented the main class (69.48 %), followed by sesquiterpenes (18.63 %), and only one diterpenoid, kaur‐16‐ene, was identified. 1,8‐Cineole (32.03 %), camphor (16.54 %), β‐elemene (5.92 %), endo‐borneol (4.94 %), limonene (4.27 %), pentatriacontane (3.91 %), and α‐pinene (3.89 %) were the major compounds. The EOs composition of Egyptian E. heterophylla ecospecies was comparable to that of other reported Euphorbia species, although it showed no correlation with Nigerian E. heterophylla ecospecies. The EOs from E. heterophylla aerial parts exhibited significant antioxidant activity. Moreover, a concentration of 100 μL L^?1 of the EOs reduced the germination, root, and shoot growth of C. echinatus by about 93.95 %, 84.6 %, and 57.8 %, respectively. Therefore, the EOs from E. heterophylla could be integrated into the control of this weed, as eco‐friendly biocontrol method. Further study is needed to characterize their allelopathic activity under field conditions as well as to evaluate their durability and biosafety.     

Chemical Composition,Antibacterial, Antioxidant and in Vitro Antidiabetic Activities of Essential Oils from Eruca vesicaria

This work describes the study of the chemical composition and bioactivity of the essential oils (EOs) of the different organs (leaves, flowers, stems and roots) from Eruca vesicaria. According to the GC and GC/MS analysis, all the EOs were dominated by erucin (4‐methylthiobutyl isothiocyanate) with a percentage ranging from 17.9 % (leaves) to 98.5 % (roots). The isolated EOs were evaluated for their antioxidant (DPPH, ABTS and β‐carotene/linoleic acid), antibacterial and inhibitory property against α‐amylase and α‐glucosidase. Most EOs exhibited an interesting α‐glucosidase and α‐amylase inhibitory potential. The roots essential oil was found to be the most active with IC₅₀ values of 0.80±0.06 and 0.11±0.01 μg mL^?1, respectively. The essential oil of roots exhibited the highest antioxidant activity (DPPH, PI=92.76±0.01 %; ABTS, PI=78.87±0.19; and β‐carotene, PI=56.1±0.01 %). The isolated oils were also tested for their antibacterial activity against two Gram‐positive and three Gram‐negative bacteria. Moderate results have been noted by comparison with Gentamicin used as positive control.     

Variability of Pinus halepensis Mill. Essential Oils and Their Antioxidant Activities Depending on the Stage of Growth During Vegetative Cycle

The impact of growth stages during vegetative cycle (B₀ – B₅) on chemical composition and antioxidant activities of Pinus halepensis Mill . needles essential oils was investigated for the first time. GC and GC/MS analyses pointed to a quantitative variability of components; terpene hydrocarbons derivatives, represented by α‐pinene (8.5 – 12.9%), myrcene (17.5 – 21.6%), p‐cymene (7.9 – 11.9%) and (Z)‐β‐caryophyllene (17.3 – 21.2%) as major components, decreased from 88.9% at B₀ growth stage to 66.9% at B₅ growth stage, whereas oxygenated derivatives, represented by caryophyllene oxide (5.4 – 12.6%) and terpinen‐4‐ol (0.4 – 3.3%) as major components, increased from 7% at B₀ growth stage to 28.4% at B₅ growth stage. Furthermore, our findings showed that essential oil of P. halepensis needles collected at B₅ growth stage possess higher antioxidant activities by four different testing systems than those collected at B₀ – B₄ growth stages. This highlighted variability led to conclude that we should select essential oils to be investigated carefully depending on growth stage, in order to have the highest effectiveness of essential oil in terms of biological activities for human health purposes.