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21.
The chemical composition of the essential oils of Satureja horvatii Šilić from two natural habitats (Mt. Orjen and Mt. Lovćen in Montenegro) and from cultivated plants (Belgrade, Serbia) were characterized. For the latter, plants from the locus classicus, i.e., Orjenske Lokve (Mt. Orjen), were transferred to Belgrade and, after three years of cultivation, the chemical composition of their essential oils at different phenological stages was analyzed. The essential oils were obtained from the aerial parts of the plants by hydrodistillation and analyzed by GC and GC/MS. The yields and chemical compositions of the S. horvatii oils showed significant differences between the plants collected in the natural habitats and those from cultivation, as well as between the plants at different phenological stages. In the populations from the natural habitats, growing in Mediterranean conditions, the most abundant oil constituents were the phenols thymol (63.7% in the samples from Mt. Orjen) or carvacrol (68.1% in the samples from Mt. Lovćen), while the oils from the cultivated plants (Belgrade), growing in continental conditions, were dominated by linalool (up to 65.8 and 55.9% in average). The basic characteristics of the essential oil from plants at the early phenological stage (before flowering) were high percentages of linalool (37.4%), thymol (27.3%), and carvacrol (12.2%). At the stage of flowering, the percentage of linalool (56.6–57.5%) increased, while those of thymol (15.5–15.8%) and carvacrol (1.4–1.5%) significantly decreased. The essential oil of plants in the full stage of fruiting was characterized by the domination of linalool (58.4 and 65.8%) and lower percentages of thymol (7.6 and 1.3%) and carvacrol (0.7 and 0.1%). In conclusion, the oil composition of S. horvatii was found to depend on the pedoclimatic conditions of the habitat and the phenological stage of the plants.  相似文献   
22.
We exposed five earthworm species, one flatworm species and the susceptible slug Deroceras reticulatum to the recommended field application rate and five times this rate of Phasmarhabditis hermaphrodita. P. hermaphrodita caused significant mortality to D. reticulatum at the recommended rate and five times the recommended rate. Survival of the earthworms and the flatworm was not different from the untreated controls. P. hermaphrodita is a safe biological control agent causing no harm to earthworms and could not be used to kill Arthurdendyus triangulatus.  相似文献   
23.
Extracts of different polarity from Baccharis trimera, Haplopappus rigidus Huperzia saururus, Maytenus ilicifolia, Satureja parvifolia and Senecio eriophyton were tested for their relaxant activity on smooth muscle using L-phenylephrine precontracted strips of corpus cavernosum obtained from Guinea pigs. Highly significant and dose dependent results were obtained with the dichloromethane extracts of H. saururus (87% of relaxation at the dose of 10 mg/ml), S. parvifolia (95% of relaxation at 2.5 mg/ml) and S. eriophyton (94% of relaxation at 5 mg/ml). Similar effects were observed with the methanol extracts of H. saururus (88% of relaxation at 10 mg/ml) and S. parvifolia (84% of relaxation at 10 mg/ml). These results were comparable to those obtained with the dichloromethane and methanol extracts of the well known Mexican species Turnera diffusa. Moreover, the aqueous extract of H. rigidus and the aqueous and methanol extracts of S. eriophyton were highly effective in a dose dependent manner (more than 90% of relaxation at the dose of 10 mg/ml). Significant results, but with a lower overall relaxant activity (about 70% of relaxation at 10 mg/ml), could also be obtained with the aqueous extract of S. parvifolia and with the dichlormethane and methanol extracts of B. trimera and M. ilicifolia. The positive controls with Sildenafil citrate at doses ranging from 0.35 to 35 microg/ml yielded moderate effects (up to 46% of relaxation at 35 microg/ml). The effects observed in the present study seem to validate the folk medicinal use of the tested plants and open new ways in the search for natural products with vasodilatory effects.  相似文献   
24.
脯氨酸是自然界中分布最广泛 ,作用最重要的渗透保护剂之一 ,同时又是高等植物中一类重要的碳源和氮源物质。为了解环境胁迫下脯氨酸的转运调节 ,从一个典型的盐生植物榆钱菠菜 (AtriplexhortensisL .)中通过cDNA文库筛选和 5′_RACE的方法获得了一个全长的cDNA (AhProT1) ,其编码蛋白与脯氨酸转运蛋白有 6 0 %~ 6 9%的同源性 ,含有 11个跨膜结构域。聚类分析表明 ,微生物和高等植物的脯氨酸转运蛋白同源程度相对高于哺乳动物。为进一步分析脯氨酸转运蛋白在植物中的功能 ,将AhProT1置于 35S启动子下转入拟南芥 (Arabidopsisthaliana)。通过同位素示踪法发现 ,与对照植物相比 ,转基因植物在根中积累更多的脯氨酸 ;在一系列不同浓度的盐胁迫试验中 ,转基因植株最高可耐受 2 0 0mmol/LNaCl,并可持续生长 ,而对照植株在 15 0mmol/LNaCl下即已死亡。  相似文献   
25.
Morphological characters and the composition of epicuticular leaf n ‐alkanes of two Satureja subspicata Bartl . ex Vis . subspecies (subsp. liburnica ?ili? and subsp. subspicata ) from nine natural populations along Dinaric Alps range were studied. Morphological characters were chosen based on ?ili? ?s subspecies separation. Seventeen n ‐alkane homologues (C19 – C35) were identified using gas chromatography/mass spectrometry (GC/MS) and GC/flame ionisation detector (FID). The most abundant n ‐alkane in all populations was n ‐nonacosane (C29), followed by n ‐hentriacontane (C31), with the exception of Diva?a population where these two alkanes were co‐dominant. Diversity and variability of n ‐alkane patterns and morphological characters and their relation to different geographic and bioclimatic parameters, including exposure, were analysed by several statistical multivariate methods (PCA, HCA, Discriminant Analysis, Mantel test). These tests showed clear separation of subsp. liburnica from subsp. subspicata , even though population Velebit showed separation from other subsp. liburnica populations based on phytochemical characters. Mantel test showed high correlation with geographical distribution in both investigated data sets. High correlation between morphological and phytochemical characters was also established. However, exposure can influence n ‐alkane profile, suggesting precaution while taking samples from natural habitats.  相似文献   
26.
The essential oil of Satureja montana L. had a broad-spectrum of antimicrobial activity against 46 species of yeasts. This high and diffused activity could be used to control potential pathogenic and spoilage yeasts. The assay of MIC toward some pathogenic and spoilage yeasts showed a range values from 0.10 to 0.25 l ml–1. The MIC and growth rate reduction assay were effective tests for quantitative evaluation of antimicrobial activity.  相似文献   
27.
Physiology and Molecular Biology of Plants - An efficient and rapid in vitro propagation system for Satureja avromanica, a rare and endangered folk medicinal plant of Iran was developed through the...  相似文献   
28.
The phytochemical composition and the antioxidant activities of the essential oil, as well as methanol and hot water extracts of endemic Satureja subspicata Vis . growing in Bosnia and Herzegovina (BiH), were described. β‐Caryophyllene, cisβ‐ocimene, and α‐pinene, identified by GC/MS and GC‐FID, were the dominant oil components. The major compound of both of extracts, identified by HPLC‐DAD, was rosmarinic acid. The analyzed essential oil showed moderate antioxidant activity. In this first report on the extracts of S. subspicata growing in BiH, the obtained results showed a high content of rosmarinic acid, as well as considerable amount of total phenols and flavonoids. Compared to the hot water extract, the methanol extract exhibits higher antioxidant potential, measured by DPPH and FRAP assay (IC50 = 0.45 g/l and 1879.43 equiv. Fe2+ μm ), while the hot water extract showed higher potential in inhibition of linoleic acid oxidation (51.7% and 61.5% for 1 and 10 g/l). A good antioxidant potential of the tested extracts indicates their potential use as antioxidants, particularly for lipid protection, and partly explains the justification of the use of this plant in traditional medicine of BiH.  相似文献   
29.
Abstract

Embryological, systematic and ecological observations on Allium parciflorum Viv. The morphological observations and the comparison with some allied species have shown a good taxonomic isolation of Allium parciflorum: this has suggested to ascribe it to a new section.

It has been observed that the female gametophyte develops according to the disporic-type, as in other species of Allium previously studied.

The distributional area in Sardinia has been considerably extended and many ecological data are also given.  相似文献   
30.
There have been few studies analysing long-term changes of gene frequencies in natural populations. This work is the first report of such changes in the land snail Cepaea hortensis (Mull).
Collections of C. hortensis were made at Silbury Hill, Wiltshire in 1957, 1963 and 1978. The banded phenotype significantly declined in frequency between 1963 and 1978. It is argued that the decline, which was statistically homogeneous at 15 separate sites within the area, was a consequence of natural selection. The average selection coefficient against the banded homozygote is estimated to have been greater than 1096.  相似文献   
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