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1.
Analysis by GC and GC/MS of the essential‐oil samples obtained from dry above‐ground parts of Hypericum rumeliacum Boiss . (collected in the flowering and fruit‐forming vegetative stages) allowed the identification of 212 components in total, comprising ≥97.8% of the total oil composition. In the flowering phase, the major identified volatile compounds were undecane (6.6%), dodecanal (10.8%), and germacrene D (14.1%), whereas α‐pinene (7.3%), β‐pinene (26.1%), (Z)‐β‐ocimene (8.5%), (E)‐β‐ocimene (10.2%), bicyclogermacrene (7.7%), and germacrene D (15.1%) were dominant in the fruit‐forming phase. Some of the minor constituents found in the studied oil samples (e.g., a homologous series of four 6‐alkyl‐5,6‐dihydro‐2H‐pyran‐2‐ones, i.e., massoia dodeca‐, trideca‐, tetradeca‐, and hexadecalactones) have a restricted occurrence in the Plant Kingdom, and their presence in Hypericum L. spp. has not been previously reported. The chemical compositions of the herein studied additional 34 oils obtained from selected Hypericum taxa were compared using multivariate statistical analysis (agglomerative hierarchical cluster analysis and principal component analysis). The results of these statistical analyses could not be used to either confirm or discard the existence of different H. rumeliacum chemotypes. However, they have implied that the volatile profile of this plant species is determined by the stage of its phenological development.  相似文献   

2.
In this protocol, 96% of bud proliferation was observed after 14 days of inoculation. Highest rate of shoot multiplication (13.3 shoots per explant) with an average shoot length of 8.2 cm was observed in Murashige and Skoog (MS) medium+2 mg/l 6-benzylaminopurine+0.25 mg/l 1-naphthaleneacetic acid+3% sucrose. Half MS (1/2 MS)+0.5 mg/l indol-3-butyric acid proved best with 73.3% rooting. The rooted shoots showed 90% survival. Genetic uniformity of the micropropagated plants with their donor plants was confirmed through random amplified polymorphic DNA molecular technique.  相似文献   

3.
Charles Kaminski 《Planta》1971,99(1):63-72
Summary The specific peroxidase (1.11.1.7) and phenoloxidase (1.10.3.1) activities are quantitatively measured during the life of Coleus, from germination until flowering. In most organs investigated, the peroxidase activity increases rapidly with growth while the phenoloxidase activity remains low. The latter activity is higher in root apices than in more differentiated regions of roots. From the results obtained it may be concluded that the phenoloxidase activity accompanies cellular proliferation. It is suggested that the peroxidase activity plays an indirect role in root initiation through its role in cellular differentiation.

Extrait d'une thèse de doctorat soutenue à la Faculté des Sciences de l'Université de Liège.  相似文献   

4.
From the hydrolysate of the crude glycosides from the roots, of Dregea volubilis(L.) Benth in Dehong, Yunnan, two α-methyl biosides Ⅰ and Ⅱ (yields: 0.016%and 0.0097%, respectively) were isolated by silica gel column chromatography. Theirchemical structures were established by interpretation of MS, IR,1H,13C-NMR, andgas chromatographic analysis of their degradation products, and comparison of thephysical properties of Ⅰ, Ⅱ and their acetates which were reported in literatures asfollows: α-methyl-pachybioside for Ⅰ, and α-methyl-[3-O-methyl-6-deoxy-D-allose(1→4)-D-olivoside] for Ⅱ. Ⅱ named α-methyl-dredehongbioside, is reported for the first time. Ⅱ, α-methyl-dredehongbioside, colorless needles (from MeOH), bitter, mp. 184–186℃,[α]D22 +74.5˚~(c= 0.52, MeOH). Anal. Cald(%) for C14H26O8:C52.17, H8.07;Found; C52.23,H8.22. Irvmaxkbr: 3370, 1443, 1419, 1375, 1268, 1218, 1168,1127,1060cm-1. MS(m/e,%): 322(M+,3),291(M+-OCH3,15), 273(M+-OCH3-H2O,12), 258,246,232, 222, 159, 145, 141, 128, 95, 87, 85, 74 (base peak, 100), 59. 1H NMRδ(CDCl3): 4.73(1H, dd, J= 4.0 Hz, J= 1.5Hz, C-1-H), 4.55(1H, d, J= 8.0Hz,C-1′-H), 3.79(1H, dd, J=3.0Hz, J= 3.0Hz, C-3′-H), 3.00(1H, dd, J= 9.0Hz,J= 9.0Hz, C-4-H), 2.22(1H, m, C-2-Ha), 1.60(1H, m, C-2-He), 1.33(3H, d,J= 6.0Hz,C-5-CH,), 1.31(3H,d,,J= 6.5Hz, C-5′-CH), 3.68(3H,s,,C-3′-OCH),3.31(3H,s,C-1-OCH). 13C NMR data were seen in Table 1. Ⅳ, tri-acetyl-α-methyl-dredehongbioside, colorless granular (from MeOH),mp. 135--137℃, [a]D22+ 88.2˚(c= 0.50, MeOH). MS(m/e, %): 488 (M+, 2), 388(M+-HOAc,2), 357(M+-OCH3-HOAc,33), 288, 187, 127, 116, 85, 74, 59, 43(basepeak, 100). 1H NMR,δ(CDCl3): 5.25(1H, ddd,.J= 11.0Hz, J=9.0Hz,.J= 5.5Hz,C-3-H), 4.86(1H, d, J= 8.0Hz, C-1′-H), 4.69 (1H, dd, J= 4.0Hz, J= 1.5Hz,C-1-H), 4.58(1H,m,C-2′-H),3.94(1H, dd, J= 3.0Hz,J= 3.0Hz,C-3′-H),3.64(1H,m,C-5-H), 3.22(1H,dd, J= 9.5Hz, J= 8.5Hz, C-4-H), 2.30(1H, m, C-2-Ha),1.67(1H,m,C-2-He), 1.31(3H, d, .J= 6.5Hz, C-5-CH3), 1.17(3H, d, J= 6.0Hz,C-5-CH3), 3.47(3H, s, C-3′-OCH3), 3.30(3H,s, C-1-OCH3), 2.10(6H, s, C-2′, C- 4′ -OCH3), 2.03(3H,s,C-3-OCH3).  相似文献   

5.
Dalbergia nigra (rosewood) is a long-lived leguminous species, which is endemic to the Brazilian Atlantic forest. Because of the high economic value of its wood, this species has been over-explored in recent years. Currently, rosewood is included in the IUCN Red List as vulnerable. We examined the genetic diversity of 87 specimens of D. nigra sampled from a continuous forest in the Veracel Reserve and Brazilwood Ecological Station, Porto Seguro, Bahia state, with random amplified polymorphic DNA markers. Grouping analyses were done using unweighted pair group method with arithmetic averages. Using the 16 most informative primers, 112 markers were obtained; 39% (44 bands) were polymorphic. A genetic similarity matrix was made based on the polymorphic bands. The dispersion graph and dendrogram analyses showed three distinct sub-populations. The degree of polymorphism was high, near that of other populations of similar species; however, it was considered low for the conservation of this species.  相似文献   

6.
Various extracts of aerial parts of Varthemia (Varthemia iphionoides Boiss) were investigated for radical-scavenging activity, antioxidative activity, and porcine pancreas α-amylase inhibitory activity. The ethanol and water extracts showed a pronounced 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, with inhibition of about 90% at a concentration of 100 μg/ml, and α-amylase inhibitory activity of about 70% at a concentration of 200 μg/ml by the 2-chloro-4-nitrophenyl α-maltotrioside (CNP-G3) degradation method. The ethanol extract was purified by column chromatography to give seven 3-methoxyflavones (17) and eudesmane sesquiterpene, selina-4,11(13)-dien-3-on-12-oic acid (8). The structures of these compounds were established by NMR, MS, and UV spectroscopy. Of 3-methoxyflavones, 5,7,4′-trihydroxy-3,6-dimethoxyflavone (1), 5,7,4′-trihydroxy-3,3′-dimethoxyflavone (2), and 5,4′-dihydroxy-3,7,3′-trimethoxyflavone (3,7,3′-tri-O-methyl-quercetin) (7) exhibited pronounced radical-scavenging activity. The antioxidative activity in the linoleic acid system was considerable in compounds 1, 2, and 5,4′-dihydroxy-3,6,7-trimethoxyflavone (4). Compounds 1, 2, 4, 5 (5,7,4′-trihydroxy-3-methoxyflavone), and 6 (5,4′-dihydroxy-3,7-dimethoxyflavone) showed markedly high inhibitory activity against porcine pancreas α-amylase. Eudesmane sesquiterpene did not show any activity.  相似文献   

7.
In the present study, an in vitro regeneration protocol for Glossonema varians (Stocks) Benth. ex Hook.f. of family Asclepiadaceae was optimized. Cotyledonary nodes of in vitro cultured seedlings were used as explants for activation of axillary shoot buds. Axillary shoot buds were initially activated on 0.1 mg L?1 6-benzylaminopurine (BAP) and then multiplied on 0.05 mg L?1 BAP. Shoots were rooted in vitro on 1/4 strength Murashige and Skoog medium containing 0.1 mg L?1 2-naphthoxyacetic acid and 100 mg L?1 activated charcoal. The cultures were maintained in a 12 h photoperiod at 40–50 μmol m?2 s?1 spectral flux photon, 25–30?±?2°C, and 60% relative humidity (RH). Up to 80% of in vitro regenerated plantlets were acclimatized on soilrite in cotton-plugged culture tubes in the greenhouse. This protocol can be a useful method to mass propagate and conserve this rare plant to balance biodiversity in the desert ecosystem.  相似文献   

8.
Verbascum olympicum Boiss. (Scrophulariaceae) were studied as a candidate plant for remediating the Ni polluted soils. The metabolic responses, such as nitrate assimilation (nitrate reductase and glutamine synthetase activity) and antioxidant system activity [superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity], of this species exposed to nickel in Hoagland's nutrient medium were investigated as remediation performance parameters. The accumulation of nickel and the variations in the content of some elements (B, Cu, Fe, Mg, Mn, Mo and Zn) and some growth parameters, such as the water content, biomass production, and contents of chlorophyll and soluble protein, were also examined. The accumulation of Ni in both the roots and leaves varied depending on the exposure times and doses. Increased oxidative stress was suggested by the increases in the activities of SOD, CAT and APX. Although some element contents were inhibited by Ni treatments, these inhibitory effects was decreased depending on the time, and even these elements are accumulated in roots. These results are the novelties in the use of this species in biotechnology.  相似文献   

9.
近年来,在应用野百合属植物农吉利(即野百合Crotalaria sessiliflora L.)治疗皮肤癌等恶性肿瘤,取得一定疗效后,曾自农吉利中分离出农吉利生物碱Ⅰ——农吉利甲素。经化学研究证明,系双稠吡咯啶生物碱——单猪屎豆碱(Monocrota-line)。实验性动物抑制试验表明,对S_(180)抑制率达45—62.5%,临床试用也取得较为满意的疗效。农吉利在我国分布尚广,但其种子细小,且农吉利生物碱含量较低(0.2%),不足应用。为了扩大药用资源,我们根据植物亲缘关系和化学成  相似文献   

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Adaptation of morphological, physiological, or life‐history traits of a plant species to heterogeneous habitats through the process of natural selection is a paramount process in evolutionary biology. We have used a population genomic approach to disentangle selection‐based and demography‐based variation in morphological and life‐history traits in the crucifer Diplotaxis harra (Forssk.) Boiss. (Brassicaceae) encountered in populations along aridity gradients in S Tunisia. We have genotyped 182 individuals from 12 populations of the species ranging from coastal to semidesert habitats using amplified fragment length polymorphism (AFLP) fingerprinting and assessed a range of morphological and life‐history traits from their progeny cultivated under common‐garden conditions. Application of three different statistical approaches for searching AFLP loci under selection allowed us to characterize candidate loci, for which their association with the traits assessed was tested for statistical significance and correlation with climate data. As a key result of this study, we find that only the shape of cauline leaves seems to be under differential selection along the aridity gradient in S Tunisian populations of Diplotaxis harra, while for all other traits studied neutral biogeographical and/or random factors could not be excluded as explanation for the variation observed. The counter‐intuitive finding that plants from populations with more arid habitats produce broader leaves under optimal conditions of cultivation than those from more mesic habitats is interpreted as being ascribable to selection for a higher plasticity in this trait under more unpredictable semidesert conditions compared to the more predictable ones in coastal habitats.  相似文献   

13.
电镜观察表明:兰花鼠尾草(Salvia farinacea Benth.)的头状腺毛(capitate trichomes)和盾状腺毛(peltate trichomes)在超微结构方面存在明显不同,盾状腺毛的分泌细胞中占优势的细胞器是质体,而头状腺毛中是内质网和质体;成熟的盾状腺毛角质层下间隙明显,而头状腺毛不明显;盾状腺毛的柄细胞的侧壁出现完全的角质化现象,而头状腺毛则无;头状腺毛的基细胞液化程度比盾状腺毛的高。  相似文献   

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In order to evaluate the allelopathic potential of Nepeta meyeri Benth., the effects of aqueous extracts (0.125, 0.25, 0.5, 1, 2.5 and 5%) prepared from roots and leaves of N. meyeri were studied on the seed germination and seedling growth of several economically important crops (barley, wheat, canola, safflower, and sunflower). Both the root and leaf extracts of N. meyeri caused a general phytotoxic effect on the seed germination and seedling growth of barley and sunflower at all concentrations. However, both the root and leaf extracts significantly increased the seedling growth of wheat, especially at the lower concentrations 0.125, 0.25 and 0.5%, whereas the higher concentrations had a neutral effect. The seed germination and the seedling growth of canola and safflower were also generally improved by both extracts, especially at lower concentrations. However, these advantages were not observed at higher concentrations, at which the extracts mostly had a phytotoxic effect on canola and safflower. The Allelopathic activity of N. meyeri depended on whether the extract was derived from the leaf or root parts of the plant. The maximum allelopathic effect occurred with leaf extracts. The results demonstrate that the aqueous extracts from N. meyeri have allelopathic potential and should be evaluated as an allelopathic species, presenting a risk or advantage to seed germination and seedling growth of crop or weed plants.  相似文献   

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To develop potential agents for slowing the progression of Alzheimer′s disease, two pairs of new enantiomeric lignans, including a couple of rarely 8′,9′-dinor-3′,7-epoxy-8,4′-oxyneolignanes named (7S, 8S)- and (7R, 8R)-pithecellobiumin A (1a/1b) and a pair of 2′,9′-epoxy-arylnaphthalenes named (7R, 8R, 8′R)- and (7S, 8S, 8′S)-pithecellobiumin B (2a/2b) were separated by chiral high performance liquid chromatography (HPLC). Their planar structures were elucidated by spectroscopic data analyses. The absolute configurations were determined by comparing of experimental and calculated electronic circular dichroism (ECD). The inhibitory activity on Aβ aggregation of all optical pure compounds was tested by ThT assay. Interestingly, enantiomeric inhibitors 1a (62.1%) and 1b (81.6%) exhibited different degrees of anti-Aβ aggregation activity. However, 2a (65.4%) and 2b (68.4%) showed similar inhibition rate. The different inhibition profiles were explained by molecular dynamics and docking simulation studies.  相似文献   

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