Liposomal incorporation of carvacrol and thymol isolated from the essential oil of Origanum dictamnus L. and in vitro antimicrobial activity

The chemical composition of the essential oils from Origanum dictamnus L. (wild and organic cultivated plant) was analysed by GC–MS. Carvacrol, thymol, p-cymene, and γ-terpinene were identified as major constituents and isolated from both samples. The above components were successfully encapsulated in phosphatidyl choline-based liposomes and the possible improvement of their antioxidant and antimicrobial activities was tested against selected microbia. The antimicrobial properties of the oils were tested by a diffusion technique against four Gram positive and four Gram negative bacteria and three human pathogenic fungi, as well as the food-borne pathogen, Listeria monocytogenes. The percentage of the encapsulated carvacrol, the major component of the oil, was determined by GC–FID. In order to investigate any possible synergistic or antagonistic effect between carvacrol/thymol and carvacrol/γ-terpinene, the antimicrobial activities of the mixtures, were also determined before and after encapsulation in liposomes. All tested compounds presented enhanced antimicrobial activities after the encapsulation. Finally, in all cases, their antioxidant activity using differential scanning calorimetry was studied, in order to gain knowledge about their oxidation stability.     

The effects of food essential oils on cardiovascular diseases: A review

Essential oils (EO) are complex secondary metabolites, which are produced by aromatic plants and identified by their powerful odors. Present studies on EO and their isolated ingredients have drawn the attention of researchers to screen these natural products and evaluate their effect on the cardiovascular system. Some EO, and their active ingredients, have been reported to improve the cardiovascular system significantly by affecting vaso-relaxation, and decreasing the heart rate and exert a hypotension activity. Several mechanisms have been proposed for the role of EO and their main active components in promoting the health of the cardiovascular system. The objective of this review is to highlight the current state of knowledge on the functional role of EO extracted from plants for reducing the risk of cardiovascular diseases and their mechanisms of action. Research on EO has the potential to identify new bioactive compounds and formulate new functional products for the treatment of cardiovascular diseases such as arterial hypertension, angina pectoris, heart failure, and myocardial infarction.     

血管紧张素Ⅱ2型受体基因多态性与山东济宁地区汉族女性原发性高血压的相关性

目的研究血管紧张素Ⅱ2型受体(AT2R)基因A1675G多态性与山东济宁地区汉族女性原发性高血压(EH)的相关性。方法随机选取山东省济宁地区汉族女性EH患者127例(EH组)和体检正常的女性119例(正常对照组),提取外周血基因组DNA,PCR扩增A1675G基因,高分辨率熔解(HRM)法测定A1675G基因的多态性。结果EH组AA、AG和GG基因型频率(分别为26.8%、53.5%和19.7%)与正常对照组(分别为27.7%、42.0%和30.3%)比较,差异均无统计学意义;等位基因频率(A:53.5%;G:46.5%)与正常对照组(A:48.7%;G:51.3%)比较,差异也无统计学意义。结论A1675G基因多态性可能与山东省济宁地区汉族女性原发性高血压无明显相关性。     

Subspace morphing theory for appearance based object identification

Object identification techniques have wide applications ranging from industry, business, military, law enforcement, to people's daily life. This research is motivated to develop a new theory for appearance based object identification with its applications in different areas. Although many successful techniques have been proposed in certain specific applications, object identification, in general, still remains as a difficult and challenging problem. In appearance based approaches, almost all the proposed methods are based on a fundamental assumption, i.e., all the images (both in the model base and to be queried) are in the same dimensions, so that the feature vectors are all in the same feature space; if images are provided with different dimensions, a normalization in scale to a pre-determined image space must be conducted. In this research, a theory for appearance based object identification called subspace morphing is developed, which allows scale-invariant identification of images of objects, and therefore, does not require normalization. Theoretical analysis and experimental evaluation show that in the situation where images are provided in different dimensions, which is common in many applications, subspace morphing theory is superior to the existing, normalization-based techniques in performance.     

走进21世纪:一流大学内涵与校园环境建设目标

在“知识经济”的概念日益深入人心,国家“科教兴国”战略,“知识创新”工程和“＠１１工程”各项措施逐步落实等大背景之下,我国许多院校纷纷提出了创建国内一流乃至世界一流大学的目标。但是,面对新世纪的诸多挑战,一流大学有何内涵,进而其校园环境建设有何要求？该文对此进行了初步研讨。     

Fumigant toxicity of essential oils from the Myrtaceae family and 1,8-cineole against 3 major stored-grain insects

Six out of 42 essential oils extracted from species of the family Myrtaceae found in Australia were shown to have potent fumigant toxicity against three major stored-grain insects: Sitophilus oryzae, Tribolium castaneum and Rhyzopertha dominica. These were the essential oils from Eucalyptus nicholii, E. codonocarpa, E. blakelyi, Callistemon sieberi, Melaleuca fulgens and M. armillaris. The LD₅₀ and LD₉₅ of the selected essential oils against S. oryzae adults were between 19.0–30.6 and 43.6–56.0 μl/l air, respectively. Also, these oils were approximately twice as toxic to T. castaneum and R. dominica at the LD₉₅. Fumigant effects of the essential oils rich in 1,8-cineole were considered to warrant further research into their potential for commercial use.     

品味古典诗歌含蓄之美,确立诗歌课件制作的诗性原则

针对中国古典诗歌含蓄这一艺术风格,在诗歌欣赏课件的制作过程中,应采取有效策略,对影画、声音、文本素材进行加工,确保为学生留下个性化的审美空间,最终完成课件的诗性再创造。     

Composition and insecticidal activity of essential oil from Pistacia lentiscus L. against Ectomyelois ceratoniae Zeller and Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)

This study reports investigations on the chemical constituents and fumigant toxicity of Pistacia lentiscus L. (Anacardiaceae) essential oil against two major stored-date insects, carob moth Ectomyelois ceratoniae Zeller and Mediterranean flour moth Ephestia kuehniella Zeller. Results showed that P. lentiscus essential oil contained terpinene-4-ol (23.32%), α-terpineol (7.12%) and β-caryophyllene (22.62%) as major compounds. Fumigant toxicity tests showed that P. lentiscus oil was more toxic to E. kuehniella (LC₅₀ = 1.84 μl/l, LC₉₅ = 5.14 μl/l) than E. ceratoniae (LC₅₀ = 3.29 μl/l, LC₉₅ = 14.24 μl/l). The fecundity and hatching rate of both insects decreased with increases in concentration or exposure time to the oil. At 136 μl/l air, fecundities and hatching rates were respectively 35 eggs/female and 42.86% for E. ceratoniae and 78 eggs/female and 29.49% for E. kuehniella.     

Biological activity and persistence of four essential oils towards the main pest of stored cowpeas, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

The use of essential oils extracted from native aromatic plants is perceived as a promising alternative to protect stored cowpeas in West Africa. However the optimal conditions for their efficiency remain to be determined. A study was therefore carried out to compare the biological activity and temperature-related persistence of four selected essential oils towards Callosobruchus maculatus, the main pest of stored cowpeas. Essential oil extracted from Ocimum americanum proved to be very toxic towards C. maculatus adults (LC₅₀ = 0.23 μl/l) while the oils from Hyptis suaveolens, Hyptis spicigera and Lippia multiflora exhibited higher LC₅₀ values (1.30 μl/l; 5.53 μl/l and 6.44 μl/l respectively). The persistence of the biological activity of the four oils was variable and that from O. americanum was most persistent. Fourteen days post-application, this oil was still as active on C. maculatus adults as it was immediately after its application. Exposure of this oil to a high temperature, close to temperatures occurring during storage in Burkina Faso in the dry season, however, resulted in a rapid decrease in its efficacy. Our results emphasize the need to take into account environmental factors such as temperature to optimize the use of promising essential oils for controlling stored-product pests in West Africa.     

Composition and biological activities of essential oils from four Heracleum species

The composition of essential oils from aerial parts of Heracleum persicum, a widely used medicinal plant, and three other Heracleum species growing wild in Iran were analysed by GC and GC–MS. Myristicin (53.6%), (E)-anethole (25.0%), hexyl butanoate (29.7%) and elemicin (41.1%) were the major compounds of Heracleum pastinacifolium, H. persicum, Heracleum rechingeri and Heracleum transcaucasicum, respectively. Cytotoxic activity assessed on three human cancer cell lines (HeLa, LS180 and Raji), showed that essential oils from H. transcaucasicum (IC₅₀ values; 0.362–0.594 mg/ml) followed by H. pastinacifolium (0.497–1.398 mg/ml) had moderate antitumoral activities. In the DPPH radical scavenging assay, H. pastinacifolium and H. persicum oils showed the highest activities with IC₅₀ values of 7.3 and 7.4 mg/ml, respectively. Antioxidant activity correlated well with the total phenolic content of the oils. None of the essential oils showed significant antimicrobial activities.