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991.
Ballero M Loi MC van Rozendaal EL van Beek TA van de Haar C Poli F Appendino G 《Fitoterapia》2003,74(1-2):34-39
Needles from a series of wild yews (Taxus baccata L.) from Sardinia were investigated for their contents of 10-deacetyl baccatin III (DAB-III, 1), paclitaxel (Taxol) (2) and taxine (3). Despite a common geographical origin, ample variation of the taxoid profile was discovered, and several samples were surprisingly devoid of all terpenoid markers above. This finding is unprecedented within the European yew, while the general lack of taxine might rationalize the observation that most plants investigated are actively and impunently browsed by goats. 相似文献
992.
El-Hassan A El-Sayed M Hamed AI Rhee IK Ahmed AA Zeller KP Verpoorte R 《Fitoterapia》2003,74(1-2):184-187
The aerial part of Leptadenia arborea has been shown to contain pinoresinol (1), syringaresinol (2), leucanthemitol (3) and E-ferulaldehyde (4). These known compounds are being reported for the first time from this plant. Among them, syringaresinol has shown an inhibitory effect against acetylcholinesterase. The IC(50) (the concentration of 50% enzyme inhibition) value of this compound was 200 microg/ml. 相似文献
993.
Furostanol saponins from Tribulus terrestris 总被引:4,自引:0,他引:4
An HPLC-ELSD-ESI-MS method has been developed for the analysis of the steroidal saponins in the aerial parts of Tribulus terrestris. Protodioscin, a new saponin (5,6-dihydroprotodioscin, neoprotodioscin) and their respective sulfates were detected. The structure of the new compound was elucidated on the basis of NMR and ESI-MS spectral analysis. 相似文献
994.
Sonia Graham Heather M. McGinness Deborah A. O’Connell A. O. Nicholls 《Small-Scale Forestry》2008,7(2):183-203
Investment in small and large-scale revegetation in Australia is growing in response to concerns regarding the sustainability
and productivity of agricultural landscapes. Site preparation and management––such as soil cultivation, weed control, fertilising,
mulching, use of treeguards and watering––are major costs associated with small-scale revegetation. The aim of this study
has been to investigate local revegetation knowledge and practices to determine the usefulness of each management practice
for achieving success and to determine whether some practices are more suited to particular climatic zones. A national online
revegetation survey was conducted to ascertain current small-scale revegetation practices and the factors that drive these
choices. Management practices were found to be strongly associated with climate. Mulch, fertiliser, weed control and watering
were applied more frequently in higher rainfall and higher temperature zones. Soil cultivation and treeguards were used more
frequently in lower rainfall and lower temperature zones. These findings suggest that there may be some benefit in modifying
existing revegetation guidelines to reflect climatic zones and management flexibility.
相似文献
Sonia GrahamEmail: |
995.
J. Roux B. Eisenberg A. Kanzler A. Nel V. Coetzee E. Kietzka M. J. Wingfield 《New Forests》2007,33(2):109-123
Plantations of Pinus spp. constitute approximately 50% of the South African forestry industry. The first aim of this study was to develop a reliable
inoculation technique to screen Pinus spp., for tolerance to infection by F. circinatum, which threatens pine forestry in South Africa. Inoculation of branches was compared with stem inoculations and we considered
the number of branches or trees required to obtain statistically significant results. Furthermore, variation in the susceptibility
of some Pinus families, clones and hybrids was considered. Results showed that branch inoculations were closely correlated with those from
stem inoculations, and that it is important to consider branch and stem diameters when assessing susceptibility of trees.
Subsequent trials using branch inoculations showed significant differences in F. circinatum tolerance amongst a range of pine species and hybrids of potential interest to forestry in South Africa. Significant differences
in susceptibility were also found among clones of two P. radiata families. The most tolerant trees were P. elliottii × caribaea and P. patula × oocarpa hybrids, while the most susceptible species were P. patula, P. greggii and hybrids of these two. This is the first trial considering the susceptibility of Pinus hybrids, Pinus clones and some P. patula provenances, and the results indicate excellent potential for breeding for tolerance to pitch canker in South Africa.
Application The accurate selection of disease tolerant planting stock for the South African forestry industry is crucially important
for the continued sustainability of this important industry. The work described here provides valuable information on an artificial
inoculation technique that will assist the industry in screening trees for tolerance to the pitch canker fungus, F. circinatum. It also provides some indication of the relative susceptibility of a number of Pinus spp., hybrids and families currently being evaluated in the country. 相似文献
996.
Abdelwahab SI Hassan LE Sirat HM Yagi SM Koko WS Mohan S Taha MM Ahmad S Chuen CS Narrima P Rais MM Hadi AH 《Fitoterapia》2011,82(8):1190-1197
The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS. 相似文献
997.
The antibacterial and antifungal activities of pinosylvin (3,5-dihydroxy-trans-stilbene), a constituent of pine, were studied and compared with those of resveratrol (3,5,4'-trihydroxy-trans-stilbene). Pinosylvin exhibited more potent growth inhibitory activity against Candida albicans and Saccharomyces cerevisiae. 相似文献
998.
A set of primers for analyzing chloroplast DNA diversity in Citrus and related genera 总被引:4,自引:0,他引:4
Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and used to analyze chloroplast diversity of Citrus and closely related genera. Fourteen cpSSR primer pairs from the chloroplast genomes of tobacco (Nicotiana tabacum L.) and Arabidopsis were found useful for analyzing the Citrus chloroplast genome (cpDNA) and recoded with the prefix SPCC (SSR Primers for Citrus Chloroplast). Eleven of the 14 primer pairs revealed some degree of polymorphism among 34 genotypes of Citrus, Fortunella, Poncirus and some of their hybrids, with polymorphism information content (PIC) values ranging from 0.057 to 0.732, and 18 haplotypes were identified. The cpSSR data were analyzed with NTSYS-pc software, and the genetic relationships suggested by the unweighted pair group method based on arithmetic means (UPGMA) dendrogram were congruent with previous taxonomic investigations: the results showed that all samples fell into seven major clusters, i.e., Citrus medica L., Poncirus, Fortunella, C. ichangensis Blanco, C. reticulata Swingle, C. aurantifolia (Christm.) Swingle and C. grandis (L.) Osbeck. The results of previous studies combined with our cpSSR analyses revealed that: (1) Calamondin (C. madurensis Swingle) is the result of hybridization between kumquat (Fortunella) and mandarin (C. reticulata), where kumquat acted as the female parent; (2) Ichang papeda (C. ichangensis) has a unique taxonomic status; and (3) although Bendiguangju mandarin (C. reticulata) and Satsuma mandarin (C. reticulata) are similar in fruit shape and leaf morphology, they have different maternal parents. Bendiguangju mandarin has the same cytoplasm as sweet orange (C. sinensis), whereas Satsuma mandarin has the cytoplasm of C. reticulata. Seventeen PCR products from SPCC1 and 21 from SPCC11 were cloned and sequenced. The results revealed that mononucleotide repeats as well as insertions and deletions of small segments of DNA were associated with SPCC1 polymorphism, whereas polymorphism generated by SPCC11 was essentially due to the variation in length of the mononucleotide repeats. 相似文献
999.
E.A. Pinkard C. Mohammed C.L. Beadle M.F. Hall D. Worledge A. Mollon 《Forest Ecology and Management》2004,200(1-3):263-277
Detailed studies have been undertaken to define pruning regimes for Eucalyptus nitens, but little is known of E. globulus responses to pruning although this is a more commonly planted species. This paper describes experiments that aimed to identify (a) levels of pruning that reduce E. globulus growth, (b) physiological processes contributing to those growth responses, (c) the incidence of decay and factors influencing decay incidence following pruning of E. globulus, and (d) comparative responses of E. nitens and E. globulus to live branch pruning. Results of a field experiment indicated that removal of between 30 and 50% of the crown length was appropriate for E. globulus plantations verging on canopy closure. The significant reduction in height growth associated with removal of 50 or 70% of crown length suggested pruning should remain below 50% of crown length if reduced stem growth of pruned trees was to be avoided. Stem volume was only significantly reduced over the period of the experiment by 70% pruning, but it was estimated that standing volume following removal of 50% of crown length would be reduced by 82 m3 ha−1 over a 20-year rotation if there were no other silvicultural interventions. The growth responses observed were probably related to large reductions in leaf area following 50 or 70% removal of crown length. Trees responded to pruning by changing patterns of biomass partitioning to favour stem growth at the expense of branch growth. A glasshouse study determined that light-saturated net CO2 uptake (Amax) increased following pruning. E. nitens seedlings had both a higher baseline Amax and higher Amax following pruning than did E. globulus, which could partially explain the greater effect of pruning on E. globulus growth than has been observed for E. nitens in other studies. This result, as well as apparently different patterns of foliage distribution through the crowns of E. globulus and E. nitens, suggested that models of pruning responses need to be parameterised for both species. In addition, a more conservative pruning regime may be appropriate for E. globulus than E. nitens. Pruning increased the frequency of branch traces with decay infection, and there was a trend towards increasing decay outbreaks with increasing pruning severity. Decay outbreaks were more likely to occur following pruning of high angle or larger diameter branches. 相似文献
1000.
M.?Z.?FanEmail author J.?M.?Dinwoodie P.?W.?Bonfield M.?C.?Breese 《Wood Science and Technology》2004,38(1):53-68
This paper examines the dimensional instability of cement bonded particleboard (CBPB) and discusses the behaviour of CBPB during cyclic changes in relative humidities (RH). The results indicated that the changes of CBPB in both mass and dimensions reflected the changes in RH; in a cycle 90–65–35–65–90%RH the change of per percentage change in RH was 1.0:1.3:1.3:2.5 for mass, 1:2:2:1 for length and 1.3:1.1:1.0:1.0 for thickness. The changes were closely related to the structure of CBPB and the nature of the cement paste and wood chips. Thickness change was double that of the length change between 65 and 35%RH and triple that between 65 and 90%RH. The rate of change in mass was much higher than that in dimensions. The hysteresis loops were dissimilar to those of other wood and wood-based materials, with the loops of mass change closed between 65 and 90%RH, while the loops for dimensional changes were open. A set of the former loops moved upward and the latter moved downward with increasing number of cycles, corresponding to an accumulated increase in mass, but decrease in dimensions. The models developed for CBPB under constant and a single changing RH were successfully applied to changes under cyclic RH.The sorption behaviour and dimensional movement of CBPB has been shown to be influenced not only by RH, but also by its intermediate history, with the maximum values for change within every phase of sorption, in both mass and dimensions, being higher for the cycling between 35–90%RH than the cycling regime 35–65–90%RH. The ratios of dimensional changes to mass change of CBPB were greater under the latter regime than under the former regime.The senior author wishes to thank Professor W.B. Banks of University of Wales, Bangor for his constructive discussions and assistance and the British Council for partly financial support. 相似文献