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1.
Ginger (Zingiber officinale Roscoe), a monocotyledonous, sterile cultigen, is widely used as a spice, flavoring agent, and herbal medicine. The pungency of fresh ginger is due to a series of homologous phenolic ketones of which [6]-gingerol is the major one. The gingerols are thermally unstable and can be converted to their corresponding shogaols, which are present in dried ginger. Fresh rhizomes of 17 clones of Australian ginger, including commercial cultivars and experimental tetraploid clones, were assayed by HPLC for gingerols and shogaols. [6]-Gingerol was identified as the major pungent phenolic compound in all samples, while [8]- and [10]-gingerol occurred in lower concentrations. One cultivar known as "Jamaican" contained the highest concentrations of all three gingerols and was the most pungent of the clones analyzed. Gingerols were stable in ethanolic solution over a 5-month period when stored at 4 degrees C. Shogaols were not identified in the extracts prepared from fresh rhizomes at ambient temperature, confirming that these compounds are not native constituents of fresh ginger. In contrast to previous findings, this study did not find significant differences in gingerol concentrations between the tetraploid clones and their parent diploid cultivar.  相似文献   

2.
Ginger oil, obtained by steam distillation of the rhizome of Zingiber officinale Roscoe, is used in the beverage and fragrance industries. Ginger oil displays considerable compositional diversity, but is typically characterized by a high content of sesquiterpene hydrocarbons, including zingiberene, ar-curcumene, beta-bisabolene, and beta-sesquiphellandrene. Australian ginger oil has a reputation for possessing a particular "lemony" aroma, due to its high content of the isomers neral and geranial, often collectively referred to as citral. Fresh rhizomes of 17 clones of Australian ginger, including commercial cultivars and experimental tetraploid clones, were steam distilled 7 weeks post-harvest, and the resulting oils were analyzed by GC-MS. The essential oils of 16 of the 17 clones, including the tetraploid clones and their parent cultivar, were found to be of substantially similar composition. These oils were characterized by very high citral levels (51-71%) and relatively low levels of the sesquiterpene hydrocarbons typical of ginger oil. The citral levels of most of these oils exceeded those previously reported for ginger oils. The neral-to-geranial ratio was shown to be remarkably constant (0.61 +/- 0.01) across all 17 clones. One clone, the cultivar "Jamaican", yielded oil with a substantially different composition, lower citral content and higher levels of sesquiterpene hydrocarbons. Because this cultivar also contains significantly higher concentrations of pungent gingerols, it possesses unique aroma and flavor characteristics, which should be of commercial interest.  相似文献   

3.
Field experiments were conducted on a Vertisol to study the effect of shade and fertilizer applications in reducing lime‐induced iron chlorosis, thereby improving crop growth and yield of ginger. Plant height and tiller number were increased with shade treatment, while the severity of iron chlorosis was reduced. Ginger growth under 66% saran netting, inter‐cropped with ochro and inter‐cropped with corn and peas, significantly outyielded those plants intercropped with corn only and those with no shade. Fertilizer applications did not have any significant effect on yield in comparison to shade treatments.  相似文献   

4.
Changes in the yields of the oleoresin and content of pungent bioactive principles: [6], [8], [10] gingerols and [6] shogaol of Jamaican ginger ( Zingiber officinale) were investigated during different stages of maturity (7-9 months). Ethanolic oleoresin extracts were prepared (95%, w/w) by cold maceration of dried ginger powder, and their percentage yields were calculated (w/w). The pungent bioactive principles in the ginger oleoresin were extracted with methanol and quantitatively analyzed by high performance liquid chromatography (HPLC). Ginger harvested at 8 months from Bourbon, Portland had the highest oleoresin yield (8.46 +/- 0.46%). [6] Gingerol was found to be the most abundant pungent bioactive principle in all the oleoresin samples investigated, with the 9 months sample from Bourbon, Portland containing the highest level (28.94 +/- 0.39%). The content of [6] gingerols was also found to be consistently high (7-9 months) in oleoresin samples from Johnson Mountain, St. Thomas (15.12 +/- 0.39 to 16.02 +/- 0.95%). The results suggest that Bourbon in Portland may be the most ideal location for cultivating ginger for high yields and quality, however, Johnson Mountain in St. Thomas could prove to be the least restrictive location, allowing for harvesting of good quality material throughout the maturity period (7-9 months).  相似文献   

5.
中国中药材生产标准缺乏、管理不完善、质量安全问题突出,通过构建科学、系统的中药材生产工程模式来指导中药材产业发展、确保产品质量安全意义重大。该研究涉及中药材生产环节,包括育种、种植、采收加工、储藏等环节,从传统道地中药材"三因子"(生物因子、环境因子、人为因子),提出现代道地中药材六属性假说(即生物自然属性、生态环境属性、加工储藏属性、品性商品属性、质量安全属性、种植管理属性)。在此基础上,利用系统学的理论、工具和方法,获得在构建生产标准、种植管理、质量安全3个体系的基础上耦合形成现代道地中药材生产工程模式的构建打下方法论的基础。按照科学性、简明性等原则,结合专家咨询法构建了3个层次、19个指标的评价指标体系,利用层次分析法确定了指标权重,利用模糊综合评价方法对段木赤灵芝生产进行实证,结果为0.71,良好,与生产实际一致。该研究不仅对中药材生产具有较高借鉴价值,也为现代农业生产工程模式研究提供理论支撑。  相似文献   

6.
In the Gilgel Gibe catchment in Ethiopia, local farmers intensify land use on Planosols by adjusting a traditional soil burning practice known as guie. The burning practice used to be applied in a cycle of shifting cultivation. However, more recently, farmers burn small plots to make fertile seedbeds for Eucalyptus seedlings in the first year before these trees are transplanted to larger plots. The purpose of this research was to assess the physico‐chemical properties of Planosols that have been subjected to burning over the last 10 yrs and evaluate the contribution of guie to land‐use intensification of these soils. Transect studies and interviews of local farmers, followed by chemical, physical and micromorphological analyses of samples from selected plots were used to compare the soil properties of recently (0–2 yrs) and formerly (3–10 yrs) burnt Planosols with those of unburnt Planosols. The analytical results show that the burning practice improved nutrient availability in the first 2 yrs after guie. Increased amounts of exchangeable aluminium (Al) were reported in the long term. Charge fingerprints illustrate that the nutrient‐buffering capacity of the soil was high shortly after the practice but subsequently decreased with time. Given the population pressure on the formerly extensively used Planosols, it is argued that the current application of guie on small, localized plots for raising Eucalyptus seedlings is well adapted to the local socio‐economic context and promotes land‐use intensification on the Planosols. The increased exchangeable Al content of former Eucalyptus seedbeds merits further in‐depth research into the biophysical sustainability of the burning practice.  相似文献   

7.
卵透明带3(zona pellucida 3,ZP3)蛋白是精卵结合最重要的受体。为了构建中华鼢鼠(Myospalax fontanierii)卵透明带3(mZP3)基因真核表达载体,本研究利用PCR方法得到加入酶切位点的mZP3片段,并将其克隆到真核表达载体pEGFP-N1上,体外转染中国仓鼠卵巢细胞(Chinese hamster ovary cell,CHO cell)和尾静脉注射昆明小鼠(Mus musculus)体内,利用RT-PCR和Western bolt技术检测其表达情况。双酶切和基因测序鉴定结果表明,所构建的表达载体是pEGFP-mZP3;倒置显微镜观察到发绿色荧光的成功转染的细胞;RT-PCR和Western bolt检测结果表明,目的基因mZP3在CHO细胞中成功表达,并且小鼠肝脏内也检测到目的基因。研究结果表明,卵透明带3基因能够在CHO真核细胞内表达,为后期基因疫苗防治中华鼢鼠提供依据。  相似文献   

8.
9.
African ginger (Siphonochilus aethiopicus), as a medicinal plant, is known for its medicinal properties, containing various antioxidant compounds and carbohydrates. Rhizome yield is improved by water regimens and fertilizers applied at plant phenological stages. However, the rhizomatous herb, which is traditionally used for the treatment of asthma, inflammation and malaria has limited information on water and nitrogen requirements for its production. This study assessed the effect of irrigation regimens (30%, 50% and 70% allowable depletion level (ADL) and nitrogen (N) levels (0, 50, 100, 150 and 200?kg?ha?1) on antioxidant activity and carbohydrates on plant leaf, root and rhizome. The interaction treatment effect of severely stressed (70% ADL) with the N application of 100?kg?ha?1 had significant effect on leaf phenolic concentration (87.02?±?2.51?mg?g?1 gallic acid equivalent). Interaction effect of moderately stressed (50% ADL) and severely stressed (70% ADL) treatment with N application rate of 0?kg?ha?1 had significant effect on plant flavonoids and phenolics in all plant parts. In plant carbohydrates, root had high sucrose content (47.68?±?9.0?mg?g?1 dry weight) with the application of low N (0?kg?ha?1) grown under severely stressed treatment. In conclusion, this implies that different S. aethiopicus parts can produce substantial amount of antioxidants and carbohydrates, as exhibited under low N and reduced water supply applied during the phenological cycle.  相似文献   

10.
Seven sampling sites in each of three biomes (Western Ghats, foothills of Western Ghats and west coast) of southwestern India were investigated to study the distribution, abundance and ecology of pill millipedes (Arthrosphaera) and associated fauna in relation to edaphic features. Abundance and biomass of Arthrosphaera and other millipedes were the highest in Western Ghats, while earthworms were in foothills. Arthrosphaera magna and Arthrosphaera spp. were common in Western Ghats and foothills respectively, while no Arthrosphaera were found in the west coast. None of the sampling sites consisted of more than one species of Arthrosphaera. Biomass of Arthrosphaera, other millipedes and earthworms significantly differed in Western Ghats (P = 9.48 × 10-7) and foothills (P = 1.35 × 10-8), as did the biomass of species of Arthrosphaera (P = 2.76 × 10-7) between Western Ghats and foothills. Correlation analysis revealed that biomass of Arthrosphaera was significantly (P = 0.01, r = 0.45) correlated with soil organic carbon rather than other edaphic features (pH, phosphate, calcium and magnesium). Distribution pattern, abundance, biomass and ecology of Arthrosphaera of Western Ghats in relation to soil qualities were compared with millipedes of other regions of the world.  相似文献   

11.
大气CO2浓度升高对谷子生长发育及玉米螟发生的影响   总被引:1,自引:2,他引:1  
人类活动导致全球大气CO_2浓度持续升高,研究大气CO_2浓度升高对C4作物谷子(Setaria italica)生长发育及虫害发生的影响,可以为谷子等C4作物制订应对气候变化栽培措施提供理论依据。本研究利用OTC(Open Top Chamber)系统,设两个CO_2浓度梯度(正常大气CO_2浓度、正常CO_2浓度+200μmol·mol-1)模拟CO_2浓度升高对谷子生长发育的影响。结果表明:大气CO_2浓度升高后,谷子净光合速率(Pn)、气孔导度(gs)、叶片蒸腾速率(Tr)和水分利用率(WUE)分别增加38.73%、27.53%、6.93%和40.56%;谷子叶片光系统Ⅱ最大光化学量子产量(Fv/Fm)和非光化学淬灭系数(NPQ)显著下降,光系统Ⅱ实际光化学量子产量(ΦPSII)和表观电子传递效率(ETR)显著增加,而对光化学淬灭系数(q P)无显著影响;此外,谷子株高、茎粗和小穗数分别增加3.41%、13.28%和13.11%;而叶重、茎重、千粒重、单株粒数和产量无显著变化,穗重和地上部分生物量分别显著下降12.8%和7.44%;大气CO_2浓度升高后,谷子灌浆期和收获期玉米螟(Ostrinia furnacalis)发生数量显著增加。大气CO_2浓度升高将有利于谷子的生长发育,但会增加玉米螟危害。  相似文献   

12.
In the mid 1980s, Asian elephant (Elephas maximus) populations were believed to persist in 44 populations on the Indonesian island of Sumatra. Twelve of these populations occurred in Lampung Province, but our surveys revealed that only three were extant in 2002. Causal factors underlying this decline include human population growth, changes in land use, and human-elephant conflict. Nevertheless, our surveys in the Province’s two national parks, Bukit Barisan Selatan and Way Kambas, produced population estimates of 498 (95% CI = [373, 666]) and 180 (95% CI = [144, 225]) elephants, respectively. The estimate for Bukit Barisan Selatan is much larger than previous estimates; the estimate for Way Kambas falls between previous estimates. The third population was much smaller and may not be viable. These are the first estimates for Southeast Asian elephant populations based on rigorous sampling-based methods that satisfied the assumptions of the models used, and they suggest that elephant numbers in these parks are of international importance. While our results suggest that Sumatra’s remaining elephant populations may be larger than expected, they also suggest that the future for these animals is bleak. Human-elephant conflict was reported around all three areas in Lampung and their elephant populations are currently threatened by habitat loss and poaching. Local solutions are possible, but will require much greater commitment by all stakeholders.  相似文献   

13.
K.M. ASHWINI  K.R. SRIDHAR   《土壤圈》2008,18(6):749-757
Seven sampling sites in each of three biomes (Western Ghats, foothills of Western Ghats and west coast) of south-western India were investigated to study the distribution, abundance and ecology of pill millipedes (Arthrosphaera)and associated fauna in relation to edaphic features. Abundance and biomass of Arthrosphaera and other millipedes were the highest in Western Ghats, while earthworms were in foothills. Arthrosphaera magna and Arthrosphaera spp. were common in Western Ghats and foothills respectively, while no Arthrosphaera were found in the west coast. None of the sampling sites consisted of more than one species of Arthrosphaera. Biomass of Arthrosphaera, other millipedes and earthworms significantly differed in Western Ghats (P =9.48 × 10−7) and foothills (P =1.35 × 10−8), as did the biomass of species of Arthrosphaera (P =2.76 × 10−7) between Western Ghats and foothills. Correlation analysis revealed that biomass of Arthrosphaera was significantly (P =0.01, r =0.45) correlated with soil organic carbon rather than other edaphic features (pH, phosphate, calcium and magnesium). Distribution pattern, abundance, biomass and ecology of Arthrosphaera of Western Ghats in relation to soil qualities were compared with millipedes of other regions of the world.  相似文献   

14.
The current geographical distribution of the Mediterranean monk seal Monachus monachus colony inhabiting the Cabo Blanco peninsula (Western Sahara-Mauritania) is described. Its distribution range has apparently not changed since surveys conducted in 1984–1988. Sightings of adults on the Tarf el Guerguerat coast, 20 km north of the known breeding caves, suggests the existence of other possible breeding groups further north. Two caves used by the seals are described for the first time. A review of historical trends in cave occupation by seals made it possible (1) to locate the so-called ‘maternity cave’, last reported in 1949; and (2) to establish that the colony, since its discovery, has occupied at least eight caves, five of which have collapsed. An index of population size based on counts of individuals of identified morphological types indicates that, during 1993–1994, the colony was composed of c.113–165 individuals (excluding pups), a larger number than previously assumed. Counting of seals at times of maximum haul-out is proposed as a tool to monitor population trends, although it is considered unreliable for estimating absolute numbers.  相似文献   

15.
中国部分板栗品种的SSR标记   总被引:5,自引:0,他引:5  
从板栗(Castanea mollissima)燕红中分离到25个SSR标记。为了鉴定这些SSR位点,在重复序列的两侧侧翼序列设计引物,并通过化学荧光检测法对6个板栗样品进行检测,共检测到20个多态性位点,每个位点的等位基因数为2~6个。挑选12个位点,通过半自动系统ABI PRISM377对中国北方24个板栗品种进行分析,这12个标记显示了高达75个等位基因的遗传多态性,每个位点的等位基因为4~10个,平均为6.3个,预期的平均杂合性为0.743(介于0.680~0.845),观察值为0.829(介于0.730~0.930)。无效等位基因估算频率显示为3个位点的正向价值,除了一个位点外,这些价值都很低,鉴定几率为7.01×10-11,亲缘关系鉴定几率非常高,为0.999,足够用于花粉流的研究。  相似文献   

16.
A laboratory mesocosm experiment was performed to study the effects of copper-enriched sewage sludge application on a mesofauna community. For 12 weeks, characteristics and changes in this defined and artificial mesofauna community structure were monitored as well as the dynamics of leaf litter decomposition. The mesofauna community comprised six species of Collembola (Folsomia fimetaria, Isotomurus prasinus, Lepidocyrtus cyaneus, Mesaphorura macrochaeta, Parisotoma notabilis, Protaphorura armata), two species of acari Oribatida (Achipteria coleoptrata, Adoristes sp.), one species of acari Gamasida (Hypoaspis aculeifer) and one species of enchytraeid (Enchytraeus crypticus). Three treatments included the addition of 22 g dry weight (DW) sludge spiked with 0, 200 and 1,000 mg Cu kg?1 DW sludge in each mesocosm, and one treatment had 66 g DW sludge spiked with 1,000 mg Cu kg?1 DW sludge added in each mesocosm. Copper, complexed with sludge due to a favourable pH, had no effect on community and litter parameters when added to low amount of sludge. In contrast, tripling the sludge dose in addition to a high dose of Cu changed in time the sludge and leaf chemical composition as well as mesofauna community structure. Responses of the mesofauna to this treatment differed between species. The abundance of species such as I. prasinus, L. cyaneus, M. macrochaeta and P. notabilis decreased, whereas the abundance of H. aculeifer increased and became dominant.  相似文献   

17.
枣果皮中酚类物质提取工艺优化及抗氧化活性分析   总被引:2,自引:3,他引:2  
为提高枣果皮中的酚类物质的提取效率,该文以马牙枣为试验材料,对枣果皮中酚类物质提取条件进行了优化,同时通过测定酚类物质清除2,2’-二苯基-1-间三硝苯基联肼(DPPH),2,2'-连氮基双(3-乙基苯并噻唑啉)-6-磺酸(ABTS)自由基和铁还原能力,分析了枣果皮提取物中酚类物质的抗氧化活性。结果显示,枣果皮中酚类物质提取的最优条件是采用70%(V/V)的甲醇、在40℃下,以1∶60的料液比浸提4h,重复浸提2次。枣果皮中酚类物质具有很强的抗氧化能力,与合成抗氧化剂2,6-二叔丁基对甲酚(BHT)相比,虽然果皮中酚类物质清除ABTS·+自由基能力略低于BHT,但其清除DPPH自由基和铁还原能力与之相当。研究结果表明枣果皮中酚类物质具有很强的抗氧化能力,在一定程度上可以取代合成抗氧化剂BHT,应用于食品加工业。  相似文献   

18.
黑土区基准坡长和LS算法对地形因子的影响   总被引:4,自引:1,他引:4  
该文结合小区实测坡长资料及Mc Cool数据,对地形因子算法中涉及的基准坡长影响和不同算法计算值的特征进行了讨论。研究表明,在坡长较小的情况下,20和22.13 m基准坡长计算得到的坡长因子相差不大,但随着坡度增加,在坡长指数的复合影响下,两者的差异渐趋增大。理论分析表明,坡长指数采用与坡度相关的变值更为合理。通过与实测数据对比发现,修正版通用土壤侵蚀模型(RUSLE)算法中的坡长因子与其更为接近,结合与Mc Cool数据的对比分析表明,研究区坡长指数更适合细沟和细沟间侵蚀比率中等的情形,或者采用RUSLE模型算法计算得到。同时研究发现,张宪奎算法、Moore算法、Desmet算法和B?hner算法计算得到的LS因子值都要比参照值小,而且4种算法与参照值的接近程度依次降低。空间分布特征而言,栅格累计算法总体较为破碎,并在平直坡面出现较多平行分布条带,而含有面积指标的其他3种算法则总体呈现光滑连续特性,但有无数据区域的存在。该结果对于研究区土壤侵蚀模型地形因子算法选择具有一定的现实意义。  相似文献   

19.
The impacts of tillage and cropping sequences on soil organic matter and nutrients have been frequently reported to affect the uppermost soil layers, but there is little published information concerning effects at greater depth. This article reports results on the distribution of soil organic carbon (SOC), active carbon (AC), N, Olsen‐P and extractable K within 100 cm in short (4 yr) and long (16 yr) term experiments under different tillage systems. Short (TT4) and long (TT16) traditional tillage are compared with conservation tillage, reduced (RT16) and non‐tillage (NT4). The results show more accumulation of SOC in the near‐surface under RT16 and NT4 in both experiments compared with traditional tillage. Moreover, greater C content occurs to 40 cm depth in the long‐term experiment. The results demonstrate the importance of time on C accumulation, not only in near‐surface layers but also at greater depths. Active C is an indicator of the increase in soil quality in the long‐term experiment. This trend is only apparent for the first 10 cm in the short‐term experiment. Patterns in N, Olsen‐P and extractable K are similar to that of SOC. However, only extractable K is significantly greater in soil under conservation tillage (RT16 and NT4) after short and long periods. Potassium availability is a good indicator of the changes caused by tillage. Our results indicate that studies of soils at depth could be very useful in long‐term experiments to demonstrate the effect of conservation tillage on C and nutrient distribution.  相似文献   

20.
近年来,由于家庭结构的变化,市场对小株型大白菜的需求日益迫切.开展负调控叶球大小发育相关基因的克隆与功能研究有助于加快小株型大白菜品种的选育进程.本研究利用RT-PCR方法从大白菜(Brassica rapa L.ssp.pekinensis)自交系福山包头叶片中分离了一个TCP第二亚族成员基因,命名为BrTCP24.BrTCP24基因编码区内无内含子,开放阅读框(ORF)全长1 221 bp,预测编码406个氨基酸.利用MEGA4.0软件将BrTCP24与拟南芥(Arabidopsis thaliana)TCP家族基因进行进化分析发现,BrT-CP24与AtTCP3同属于一个分支,在进化上具有较近的亲缘关系.用DNAMAN软件对BrTCP24和AtTCP3蛋白进行多序列联配分析发现,二者的氨基酸一致性可达到55.17%,在保守的TCP结构域其一致性可高达91.53%.这种进化上的亲缘关系和序列上的保守性,暗示二者可能具有类似的生物学功能.通过半定量RT-PCR分析发现,BrTCP24基因在大白菜的根、茎、莲座叶、包叶、盛开的花、受精后10 d的果夹和花蕾中均有表达,其中莲座叶中表达量最高,根、包叶、盛开的花、受精后10d的果夹和花蕾中的表达量次之,短缩茎中表达量最低;另外,在5 μmol NAA处理的12h内BrTCP24的表达水平未发生明显变化.为进一步研究BrTCP24基因的功能,我们构建了转化拟南芥的正义表达载体(35S::BrTCP24),并转入拟南芥中.通过卡那霉素筛选以及基因组DNA PCR鉴定,共得到17株转基因拟南芥植株.通过对其中5株的RT-PCR分析发现,它们都能够转录表达BrTCP24基因.利用荧光实时定量PCR方法对部分转基因植株的插入拷贝数进行检测发现,BrTCP24基因以单拷贝形式插入拟南芥基因组.进一步研究发现,与野生型拟南芥相比,过量表达BrTCP24基因可导致转基因拟南芥的下胚轴和叶器官明显减小.此外,过量表达BrTCP24基因抑制了与器官大小相关基因ANT、AtEXP10、AtGRF5、AtGIF1和CycD3;1的表达.这些结果表明,大白菜BrTCP24基因可能通过抑制细胞的生长参与调节植物器官大小的发育.  相似文献   

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