新疆药用植物牛至内生细菌多样性与抗菌活性

【背景】植物内生菌作为微生物群落中一类非常重要的组成部分,在多个领域都有广泛的应用价值,如促进植物生长、抵抗病虫害、生物固氮、降解有毒有害化合物等。【目的】进一步丰富新疆野果林苹果腐烂病害的生防资源以及分析牛至内生细菌多样性特征。【方法】通过纯培养方法,对健康植物牛至组织进行内生细菌的分离纯化,并进行16S rRNA基因序列分析;再利用平板对峙法筛选具有抑制苹果腐烂病病原菌生长的内生细菌。【结果】共分离到168株内生细菌,最终确定为4门5纲8目12科17属,其中优势属为芽胞杆菌属(Bacillus)。由分离实验结果可知,M1号TSA培养基,M5号组氨酸-棉子糖培养基和M6号NA培养基是分离牛至内生细菌较为理想的培养基;采自新源县野果林的牛至内生细菌多样性较为丰富,在牛至根部内生细菌种类更多;通过拮抗实验共筛选出59株牛至内生细菌具有较好的抑菌效果。【结论】新疆药用植物牛至内生细菌的物种多样性较为丰富,而且富含一批有效抑制野苹果腐烂病病原菌生长的内生细菌菌株。因此,本研究在新疆野果林苹果腐烂病的生物防治和药用植物内生细菌种质资源的填补等方面具有重要意义。     

Contemporary seasonal and altitudinal variations of leaf structural features in oregano (Origanum vulgare L.)

The effects of elevation (200, 950 and 1760 m) and season (April-October) on leaf morphological, anatomical, ultrastructural, morphometrical and photosynthetic parameters were studied in Origanum vulgare plants. Observations aimed at the determination of the alterations in leaf structure and function associated with differential growth and adaptation of plants. Raising elevation results in a progressive decrease of plant height. During the growing period, summer plants are taller than spring and autumn plants at all elevations examined. In high-altitude populations (O. vulgare ssp. vulgare), the blade size becomes reduced in June leaves as compared with October leaves, while it does not change remarkably in low-altitude populations (O. vulgare ssp. hirtum). Leaf thickness remains more or less stable during the growing period. Expanded leaves in June and October at 200 m elevation contain dark phenolics only in their epidermis, whereas leaves of August are densely filled with phenolics in all of their tissues. In June at 1760 m elevation, leaves are devoid of phenolics, which, however, occur in the epidermis of the leaves in August and October. At higher altitudes, larger mesophyll chloroplasts with more starch grains are present in June leaves, whereas in August and October leaves chloroplasts are smaller with fewer starch grains. Leaf stomata and non-glandular hairs increase in number from the lowland to the upland habitats, whereas glandular hairs decrease in number. During the growing season, the density of stomata and of glandular and non-glandular hairs progressively increases. In the low- and mid-altitude oregano populations, leaf chlorophyll a content and PSII activity significantly increase in October, whereas they simultaneously decrease in the high-altitude population, suggesting a phenomenon of chilling-induced photoinhibition. The highest photochemical efficiency of PSII appears in the mid-altitude population (having characteristics intermediate between those of O. vulgare ssp. hirtum and ssp. vulgare) where environmental conditions are more favourable. This conclusion is also confirmed by the observation that the 950 m O. vulgare population has larger and thicker leaves with highly developed palisade and spongy parenchymas.     

Enantioselective monoterpene alcohol acetylation in Origanum, Mentha and Salvia species

Selected plants within the Origanum, Mentha and Salvia genera, that contain significant amounts of chiral volatile alcohols and their related acetates, exhibit remarkable enantioselectivity of alcohol acetyl transferase (AAT) activity and particularly can discriminate between linalool enantiomers. Origanum dayi AAT produced almost enantiomerically pure (R)-linalyl acetate by enzymatic acetylation of racemic linalool, whereas the closely related O. majorana AAT produced a mixture of (R)- and (S)-linalyl acetate with a ratio of 6:4. V(max) of O. dayi acetylation activity was 30-fold higher for (R)-linalool, whereas in O. majorana no such differences were found.     

Ratios of cis- and trans-Sabinene Hydrate in Origanum majorana L. and Origanum microphyllum (Bentham) Vogel

(+)-cis-Sabinene hydrate and (+)-trans-sabinene hydrate are the main monoterpenes found in marjoram (Origanum majorana), but can also be found in other Origanum species as well, as in e.g. Melaleuca alternifolia. The synthesis of sabinene hydrate in marjoram (Origanum majorana) is performed by sabinene hydrate synthase. It is claimed, that both, (+)-cis- and (+)-trans-sabinene hydrate are produced by the same enzyme in an exact ratio of 10:1. To verify this in vitro result in vivo, we analysed single plants of 20 different genotypes of Origanum majorana and of three different populations of Origanum microphyllum and calculated the ratios of (+)-cis- to (+)-trans-sabinene hydrates. In Origanum majorana a constant ratio of 20:1 could be found, whereas in Origanum microphyllum the ratio did not prove to be constant.     

Inhibitory effect of ursolic acid purified from Origanum majorana L on the acetylcholinesterase

We screened 139 herbal spices in search of the acetylcholinesterase (AChE) inhibitor from natural resources. AChE inhibitors, which enhance cholinergic transmission by reducing the enzymatic degradation of acetylcholine, are the only source of compound currently approved for the treatment of Alzheimer's Disease (AD). Among these herbs, edible plants and spices, the ethanol extract from Origanum majorana L. showed the highest inhibitory effect on AChE in vitro. By sequential fractionation of Origanum majorana L. the active component was finally identified as ursolic acid (3 beta-Hydroxyurs-12-en-28-oic acid). The ursolic acid of Origanum majorana L. inhibited AChE activity in a dose-dependent and competitive/non-competitive type. The Ki value (representing the affinity of the enzyme and inhibitor) of Origanum majorana L. ursolic acid was 6 pM, and that of tacrine was 0.4 nM. The concentration required for 50% enzyme inhibition of the active component (IC50 value) was 7.5 nM, and that of tacrine was 1 nM. This study demonstrated that the ursolic acid of Origanum majorana L. appeared to be a potent AChE inhibitor in Alzheimer's Disease.     

致肠炎常见菌对牛至浸膏的敏感性试验

试验了３１株致肠炎常见菌对牛至浸膏的敏感性,结果表明,该浸膏对上述３１株菌均有不同程度的杀菌和抑菌作用。     

Phenolic antioxidants from herbs and spices

Spices and herbs are recognized as sources of natural antioxidants and thus play an important role in the chemoprevention of diseases resulting from lipid peroxidation. Our studies on spices and herbs have given us over a hundred compounds, known and new, having high antioxidant activity. From the Labiatae family, Rosmarinus officinalis, Thymus vulgaris, Origanum vulgare and O. majorana gave 26 active comopounds. Over 40 antioxidative compounds from Zingiber officinale, 26 compounds from Curcuma domestica = C. longa, C. xanthorrhiza and Z. cassumunar were determined, these belonging to the family Zingiberaceae. From the family Myrtaceae, 25 compounds from the berries of Pimenta dioica were determined and 3 carbazoles were isolated from Murraya koenigii. Structure-activity relationships of some of the isolated compounds were also discussed.     

Activity of essential oils and individual components against acetyl- and butyrylcholinesterase

We have tested acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of nineteen essential oils obtained from cultivated plants, namely one from Anethum graveolens L. (organic fertilizer), two from Foeniculum vulgare Mill. collected at fully-mature and flowering stages (organic fertilizer), two from Melissa officinalis L. (cultivated using organic and chemical fertilizers), two from Mentha piperita L. and M. spicata L. (organic fertilizer), two from Lavandula officinalis Chaix ex Villars (cultivated using organic and chemical fertilizers), two from Ocimum basilicum L. (green and purple-leaf varieties cultivated using only organic fertilizer), four from Origanum onites L., O. vulgare L., O. munitiflorum Hausskn., and O. majorana L. (cultivated using organic fertilizer), two from Salvia sclarea L. (organic and chemical fertilizers), one from S. officinalis L. (organic fertilizer), and one from Satureja cuneifolia Ten. (organic fertilizer) by a spectrophotometric method of Ellman using ELISA microplate-reader at 1 mg/ml concentration. In addition, a number of single components widely encountered in most of the essential oils [gamma-terpinene, 4-allyl anisole, (-)-carvone, dihydrocarvone, (-)-phencone, cuminyl alcohol, cumol, 4-isopropyl benzaldehyde, trans-anethole, camphene, iso-borneol, (-)-borneol, L-bornyl acetate, 2-decanol, 2-heptanol, methyl-heptanol, farnesol, nerol, iso-pulegol, 1,8-cineole, citral, citronellal, citronellol, geraniol, linalool, alpha-pinene, beta-pinene, piperitone, iso-menthone, menthofurane, linalyl oxide, linalyl ester, geranyl ester, carvacrol, thymol, menthol, vanilline, and eugenol] was also screened for the same activity in the same manner. Almost all of the essential oils showed a very high inhibitory activity (over 80%) against both enzymes, whereas the single components were not as active as the essential oils.     

Ursolic acid of Origanum majorana L. reduces Abeta-induced oxidative injury

Amyloid beta protein (Abeta) increases free radical production and lipid peroxidation in PC12 nerve cells, leading to apoptosis and cell death. The effect of ursolic acid from Origanum majorana L. on Abeta-induced neurotoxicity was investigated using PC12 cells. Pretreatment with isolated ursolic acid and vitamin E prevented the PC12 cell from reactive oxygen species (ROS) toxicity that is mediated by Abeta. The ursolic acid resulted in decreased Abeta toxicity assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and trypan blue assay. Thus, treatment with these antioxidants inhibited the Abeta-induced neurotoxic effect. Therefore, these results indicate that micromolar Abeta-induced oxidative cell death is reduced by ursolic acid from Origanum majorana L.     

牛至药液和香连药液的抗菌作用

试验了牛至药液和香连药液对来自不同菌属的致肠炎常见菌的抗菌作用 ,比较了二药的抗菌效果。结果表明 :牛至药液的杀菌效果优于香连药液 ,抑菌效果则二药液相近。     

Antifungal effects of essential oils from oregano and fennel on Sclerotinia sclerotiorum

AIMS: The antifungal effects of essential oils of oregano (Origanum syriacum var. bevanii) and fennel (Foeniculum vulgare) were evaluated against Sclerotinia sclerotiorum. Effects of the essential oils on morphological structures of hyphae and sclerotia were studied under light and scanning electron microscopes (SEM). METHODS AND RESULTS: Inhibitory effects of volatile and contact phases of the essential oils used were determined on hyphae and sclerotia. Both essential oils have a marked antifungal effect against S. sclerotiorum. Soil amendment with essential oils has significant effect on reducing sclerotial viability. Both essential oils significantly inhibited the fungal growth in soil, thereby increasing the number of surviving tomato seedling by 69.8% and 53.3%, respectively. Light and SEM observations on pathogen hyphae and sclerotia revealed considerable morphological alterations in hyphae and sclerotia. CONCLUSIONS: The significant reduction in the mycelial growth and germination of sclerotia would greatly reduce the pathogen inoculum source. This may influence the rate of disease development in soil. SIGNIFICANCE AND IMPACT OF THE STUDY: Considering the reduction in the number of diseased plants in infested soil amended with essential oils, we concluded that oregano and fennel essential oils could be used as possible bio fungicides alternative to synthetic fungicides against phytopathogenic fungi.     

Identification of a repeat sequence of rye DNA in wheat and related species

Polymerase chain reaction (PCR) and enhanced chemiluminescence (ECL) were used to determine the distribution of the rye-specific sequence contained in the pSc119.1 probe among wheat and related species. A specific pair of primers targeting this rye-specific sequence was used. A 745-bp fragment, the predicted size of pSc119.1, was present inSecale cereale, Triticum aestivum, XTriticosecale, Hordeum vulgare, H. bogdanii, andH. parodii. PCR results were verified by hybridizing the rye-specific probe pSc119.1 to dotblots of DNA from the different species used. Strong hybridization signals detected by ECL were consistent with the PCR results. The results demonstrate the effectiveness of PCR and dot-blot ECL in screening plants for defined DNA sequences, and indicate that pSc119.1 has counterparts with strong homology inT. aestivum, H. vulgare, H. bogdanii, andH. parodii.     

Infraspecific variation of leaf anatomy in Origanum vulgare grown wild in Greece

The histological components of the leaf were studied in dried herbarium material of the three Origanum vulgare subspecies (subsp. hirtum , subsp. viridulum and subsp. vulgare ) grown wild in Greece. These three, geographically distinct, taxa showed remarkable differences in their leaves. The leaves of subsp. hirtum grown in the Mediterranean climatic zone of Greece are characterized by thick cutinized outer walls of the epidermal cells and a thick mesophyll with highly developed chlorophyllous tissues. Peltate glandular trichomes and stomata are numerous on bom leaf surfaces. The thickness of the mesophyll decreases in the other two subspecies grown in the northern part of the country, where a Continental type of climate occurs. The number of glandular trichomes and stomata also decreases. Besides these differences, a noticeable reduction in the size of the essential oil-accumulating subcuticular chamber of the glandular trichomes and in the number of the peribasal cells, has also been recorded in die plants of subsp. vulgare and viridulum.     

The essential oil of Origanum vulgare L. ssp. vulgare growing wild in vilnius district (Lithuania)

The plants of wild Origanum vulgare L. ssp. vulgare were collected in 10 localities of Vilnius district (Lithuania) in 1995-1999. The main constituents of the essential oils from 8 localities were beta-ocimene (14.9-21.6%), germacrene D (10.0-16.2), beta-caryophyllene (10.8- 15.7%) and sabinene (6.6- 4.2%). The essential oils from two localities contained only three above compounds as major components: germacrene D, beta-ocimene and sabinene or beta-caryophyllene, beta-ocimene and germacrene D. Three chemotypes of essential oils were identified. The main chemotype was beta-ocimene germacrene D-beta-caryophyllene. The terpenic hydrocarbons made up 52.8-80.6% of the essential oils. The 42 identified components made up 85.6-98.0% of the essential oil.     

Chemical composition and fumigant toxicity of some essential oils against Ephestia kuehniella

The chemical constituents of some essential oils extracted from aromatic plants (savory, Satureja thymbra L.; Turkish oregano, Origanum onites L.; myrtle, Myrtus communis L.; marjoram, Origanum majorana L.; laurel, Laurus nobilis L.; lemon, Citrus limon L.; sticky goosefoot, Chenopodium botrys L.; and tansy, Tanecetum armenum [DC.] Suchultz Bip.) were analyzed by gas chromatography-mass spectrometry. Fumigant toxicity of volatile compounds was tested against Mediterranean flour moth, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), eggs and adults. Percentage of mortality and longevity of E. kuehniella adults were estimated after essential oil treatments. LC50 and LC99 values were determined for each exposure time for each essential oil. Marjoram and lemon oils were the most effective of all the essential oils tested. The major components were linalool, 1.8-cineole, citral, 2-(4a.8-dimethyl-1.2.3.4.4a.5.6.7-octahydro-naphthalen-2-yl)-prop-2-en-l-ol, and p-cymene for marjoram, laurel, lemon, goosefoot, and tansy, respectively. The LC50 and LC99 values were estimated as 3.27 and 5.13 microl liter(-1) air for marjoram and 4.05 and 5.57 microl liter(-1) air for lemon essential oils at the longest exposure time. Decreasing longevity effect of marjoram and lemon was more prominent compared with other essential oils. We suggest that essential oils obtained from certain aromatic plants have potential as fumigants for stored product pests.     

Micropropagation of oregano (<Emphasis Type="Italic">Origanum vulgare×applii</Emphasis>) from meristem tips

Summary ‘Mendocino’ oregano (Origanum vulgare × applii) cultivated in Argentina has been subject to progressive yield loss as a consequence of continuous vegetative propagation. A method of reducing damage to the shoot tip during sterilization procedures for micropropagation is proposed. Single shoot cuttings are less sensitive to disinfecting substances than green tips. Meristems taken from young plantlets that grew in vitro produced less oxidation during the culture than those dissected immediately after disinfecting from plants grown in the field. This work describes the effects of the growth regulators benzyladenine (BA) and naphthaleneacetic acid (NAA) at various concentrations and combinations on micropropagation of O. vulgare × applii. Treatment with 0.28 μM BA and 0.53 μM NAA gave greatest effiency (mean: 22.2 nodes per plantlet). After 60 d 100% of rooted plantlets could be formed per explant under optimum conditions.     

Characterization of 215 simple sequence repeat markers in creeping bentgrass (Agrostis stolonifera L.)

Creeping bentgrass (Agrostis stolonifera L.) is a versatile, cross-pollinated, temperate and perennial turfgrass species. It occurs naturally in a wide variety of habitats and is also cultivated on golf courses, bowling greens and tennis courts worldwide. Isozymes and amplified fragment length polymorphisms (AFLPs) have been used to determine genetic diversity, and restriction fragment length polymorphisms (RFLPs) and random amplified polymorphic DNA (RAPDs) were used to construct a genetic linkage map of this species. In the current report, we developed and characterized 215 unique genomic simple sequence repeat (SSR) markers in creeping bentgrass. The SSRs reported here are the first available markers in creeping bentgrass to date. Eight hundred and eighteen alleles were amplified by 215 SSR loci, an average of 3.72 alleles per locus. Fifty-nine per cent of those alleles segregated in a 1:1 Mendelian fashion (P > 0.05). Twenty-two per cent had a distorted segregation ratio (P ≤ 0.05). These SSR markers will be useful for assessing genetic diversity in creeping bentgrass and will be important for the development of genetic linkage maps and identifying quantitative trait loci. These markers could enhance breeding programmes by improving the efficiency of selection techniques.     

45S rDNA在小麦及其近缘物种染色体上的分布

将染色体C-分带和原位杂交技术相结合,系统研究了45S rDNA在栽培一粒小麦、野生二粒小麦、普通小麦、大麦、簇毛麦、硬簇麦、六倍体燕麦及鹅观草等物种染色体上的分布情况。这些物种染色体的次缢痕区都有45S rDNA位点, 某些非随体染色体上也有45S rDNA位点分布。以小麦—鹅观草1Rk^#1二体附加系为材料,通过顺序C分带-FISH技术首次将一个45S rDNA定位到1Rk^#1染色体短臂末端。     

Simple sequence repeat analyses of interspecific hybrids and MAALs of <Emphasis Type="Italic">Oryza </Emphasis><Emphasis Type="Italic">officinalis</Emphasis> and <Emphasis Type="Italic">Oryza sativa</Emphasis>

Wild rice is a valuable resource for the genetic improvement of cultivated rice (Oryza sativa L., AA genome). Molecular markers are important tools for monitoring gene introgression from wild rice into cultivated rice. In this study, Simple sequence repeat (SSR) markers were used to analyze interspecific hybrids of O. sativa-O. officinalis (CC genome), the backcrossing progenies and the parent plants. Results showed that most of the SSR primers (335 out of 396, 84.6%) developed in cultivated rice successfully amplified products from DNA samples of wild rice O. officinalis. The polymorphism ratio of SSR bands between O. sativa and O. officinalis was as high as 93.9%, indicating differences between the two species with respect to SSRs. When the SSR markers were applied in the interspecific hybrids, only a portion of SSR primers amplified O. officinalis-specific bands in the F(1) hybrid (52.5%), BC(1) (52.5%), and MAALs (37.0%); a number of the bands disappeared. Of the 124 SSR loci that detected officinalis-specific bands in MAAL plants, 96 (77.4%) showed synteny between the A and C-genomes, and 20 (16.1%) showed duplication in the C-genome. Sequencing analysis revealed that indels, substitution and duplication contribute to the diversity of SSR loci between the genomes of O. sativa and O. officinalis.     

Nematicidal activity of essential oils and volatiles derived from Portuguese aromatic flora against the pinewood nematode, Bursaphelenchus xylophilus

Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, were screened for their nematicidal activity against the pinewood nematode (PWN), Bursaphelenchus xylophilus. The essential oils were isolated by hydrodistillation and the volatiles by distillation-extraction, and both were analysed by GC and GC-MS. High nematicidal activity was achieved with essential oils from Chamaespartium tridentatum, Origanum vulgare, Satureja montana, Thymbra capitata, and Thymus caespititius. All of these essential oils had an estimated minimum inhibitory concentration ranging between 0.097 and 0.374 mg/ml and a lethal concentration necessary to kill 100% of the population (LC(100)) between 0.858 and 1.984 mg/ml. Good nematicidal activity was also obtained with the essential oil from Cymbopogon citratus. The dominant components of the effective oils were 1-octen-3-ol (9%), n-nonanal, and linalool (both 7%) in C. tridentatum, geranial (43%), neral (29%), and β-myrcene (25%) in C. citratus, carvacrol (36% and 39%), γ-terpinene (24% and 40%), and p-cymene (14% and 7%) in O. vulgare and S. montana, respectively, and carvacrol (75% and 65%, respectively) in T. capitata and T. caespititius. The other essential oils obtained from Portuguese flora yielded weak or no activity. Five essential oils with nematicidal activity against PWN are reported for the first time.