遮光对南方红豆杉生长及紫杉醇含量的影响

通过设计1年以上的长期遮光处理,对南方红豆杉(Taxus chinensis var.mairei)当年生幼苗、3年生和5年生幼株的生长及5年生幼株不同遮光处理后针叶中紫杉醇和其前体(10-脱酰基巴卡丁Ⅲ)含量进行了测定.结果表明,光照是影响红豆杉幼苗和幼株生长的一个重要环境因子,当年生南方红豆杉幼苗必须在荫蔽环境下才能保证高的成活率和健康的生长态势,对于3龄红豆杉幼株,全光照下,50%左右的红豆杉幼株死亡,对于5龄南方红豆杉植株,30%遮光率下有利于其健康生长;5年生南方红豆杉幼株全光照处理下的植株针叶中紫杉醇和10-脱酰基巴卡丁Ⅲ含量高于其他光照条件下的植株.南方红豆杉幼株针叶紫杉醇和10-脱酰基巴卡丁Ⅲ的最佳积累光照条件与其最适宜的生长发育光照环境并不完全平行.     

红豆杉植株紫杉醇含量研究进展(综述)

影响红豆杉中紫杉醇含量的因素较多。为了提高红豆杉紫杉醇及其衍生物的含量,国内外已开展大量研究,其中多数是以天然红豆杉为研究对象。研究表明,不同种类、树龄、器官、物候期、生长环境等因子对天然红豆杉中紫杉醇含量均有影响。本文综述了影响红豆杉紫杉醇含量的各种因子,并对紫杉醇测定方法、天然红豆杉与人工红豆杉中紫杉醇含量以及红豆杉中其它紫杉烷类化合物含量等进行了比较。     

南方红豆杉生长发育及其紫杉醇含量与环境因子的关系

研究了人工种植的3年生南方红豆杉的生长发育特征及其枝叶中紫杉醇的含量,并观测了其生长环境因子的动态特征。通过对南方红豆杉的生长发育特征以及其枝叶中紫杉醇含量与生长环境因子进行相关分析发现,南方红豆杉生长发育与空气和土壤湿度呈极显著的正相关,与空气和土壤温度、土壤N和K含量、土壤有机质和土壤紧实度呈正相关,与净辐射和土壤P含量呈负相关,但相关关系不显著,说明高温、高湿以及遮荫有利于南方红豆杉的生长,且对土壤P含量有较高需求;南方红豆杉枝叶中紫杉醇含量与空气和土壤湿度、土壤N、P和K含量呈负相关,与净辐射、空气和土壤温度、土壤有机质和土壤紧实度呈正相关,但相关关系均不显著,说明高温、高光强和干旱促进南方红豆杉枝叶中紫杉醇含量的增加,且紫杉醇含量的增加对土壤中N、P和K含量有一定的需求,尤其是N和K,对P需求不大;南方红豆杉生长发育与其枝叶中紫杉醇含量呈负相关,相关关系也不显著,推测紫杉醇可能是南方红豆杉的防御物质,以促使南方红豆杉抵御高温、干旱和高光强等不良环境。     

不同地理种源南方红豆杉中紫杉醇和10-DAB含量及影响因子

选择福建省梁野山、龙栖山、闽侯旗山、南靖书洋乡和南平大坪村南方红豆杉(Taxus chinensis var.marei)天然群体分布相对集中区,采集胸径相同的南方红豆杉的当年生针叶和树皮并取树下土壤样品.利用超高效液相色谱分析测定南方红豆杉当年生针叶及树皮中紫杉醇及10-去乙酰基巴卡亭Ⅲ(10-deacetylbaccatin Ⅲ,10-DAB)含量,另测定土壤pH值、速效磷、速效氮、铁、钙、镁、锌含量.结果表明,不论是紫杉醇还是10-DAB含量,不同地理种源南方红豆杉间差异均较大,说明地理位置对于红豆杉中紫杉醇和10-DAB含量具有明显的影响;树皮中紫杉醇含量与土壤中铁含量显著相关(P<0.01);南方红豆杉当年生针叶中及树皮中紫杉醇含量与各种源地气象因子的相关性不显著(P>0.05).     

红豆杉组织培养及其产物紫杉醇研究进展

该文对红豆杉组织培养过程中外植体的选择、培养基、培养方法等方面研究进展进行了综述。获取抗癌药物紫杉醇主要途径有:红豆杉组织培养途径、人工种植途径、化学合成及微生物生产途径等。     

不同地理种源南方红豆杉中紫杉醇和10-DAB含量及影响因子

选择福建省梁野山、龙栖山、闽侯旗山、南靖书洋乡和南平大坪村南方红豆杉（Taxus chinensis var. marei）天然群体分布相对集中区,采集胸径相同的南方红豆杉的当年生针叶和树皮并取树下土壤样品。利用超高效液相色谱分析测定南方红豆杉当年生针叶及树皮中紫杉醇及10-去乙酰基巴卡亭Ⅲ（10-deacetylbaccatin Ⅲ, 10-DAB）含量,另测定土壤pH值、速效磷、速效氮、铁、钙、镁、锌含量。结果表明,不论是紫杉醇还是10-DAB含量,不同地理种源南方红豆杉间差异均较大,说明地理位置对于红豆杉中紫杉醇和10-DAB含量具有明显的影响;树皮中紫杉醇含量与土壤中铁含量显著相关（P＜0.01）;南方红豆杉当年生针叶中及树皮中紫杉醇含量与各种源地气象因子的相关性不显著（P＞0.05）。     

南方红豆杉试管微芽诱导培养及其紫杉醇类化合物的积累

以南方红豆杉幼茎段和茎尖为外植体,以wPM为基本培养基,单一添加不同浓度的KT、TIBA、ZT和6-BA进行芽诱导培养。结果表明：各自添加0．4mg·L-1KT、3．0mg·-1TIBA、0．1mg·L-1 ZT和0．01mg·L-1 6-BA时的芽诱导率最高。培养50d的试管微芽中紫杉醇和10一去乙酰基巴卡亭III（10．DABIII）的积累量比天然南方红豆杉嫩枝高2倍以上,试管微芽中10一DABIII比紫杉醇高,且二者均随芽诱导率的增加而增加,当芽诱导率达最高时亦达到最高。TIBA所诱导芽短而粗壮。     

红豆杉内生真菌产紫杉醇研究进展

本文综述了近年来产紫杉醇的红豆杉内生真菌分离和筛选、代谢和发酵的研究进展。     

小剂量连续诱导法提高红豆杉细胞中紫杉醇含量

比较了小剂量连续诱导与一次性大剂量加入诱导子对红豆杉细胞H2O2含量、生物量及紫杉醇含量等方面影响的差异。结果表明：小剂量连续诱导组H2O2相对含量、生物量及紫杉醇含量都将一次性大剂量加入诱导子组高。前者三个指标的值分别为：17．6OD410／g、27.84g/100ml、5.0(1／万DW）,后者三个指标的值分别为：12OD40／g、24.51g/100ml、1.2(1／万DW）。     

稀土元素对南方红豆杉细胞培养及紫杉醇含量的影响

红豆杉属植物中的紫杉醇 (ｔａｘｏｌ)属萜类化合物 ,对白血病、转移性乳腺癌、卵巢癌、恶性黑色素瘤均有疗效 ,曾被誉为“最好的抗癌制剂”[植物学通报 ,1995 ,12 (3) :8～ 14]。植物组织细胞培养生产紫杉醇 ,特别是用稀土为诱导子提高红豆杉细胞合成与紫杉醇的释放 [天津农业科学 ,1998,4(1) :2 3～ 2 6 ;稀土 ,2 0 0 0 ,2 1(2 ) :49～ 5 1;中国稀土学报 ,1998,16 (1) :5 6～ 6 0 ]已成为当前研究的热点。本文所用的南方红豆杉(Ｔａｘｕｓｃｈｉｎｅｎｓｉｓｖａｒ ｍａｉｒｅｉ)无性系由南方红豆杉芽诱导、多次继代、液体培养而来。按杨…     

Two new alkaloidal taxoids from the needles of Taxus canadensis

Two new taxanes with a dimethylamino group on the C-5 side chain were identified for the first time in the needles of the Canadian yew, Taxus canadensis. Their structures were characterized as 7beta,10beta,13alpha-triacetoxy-5alpha-(3'-dimethylamino-3'-phenylpropanoyl)oxy-2alpha-hydroxy-2(3-->20)abeotaxa-4(20),11-dien-9-one (1) and 2alpha,10beta-diacetoxy-9alpha-hydroxy-5alpha-(3'-dimethylamino-3'-phenylpropanoyl)oxy-3,11-cyclotax-4(20)-en-13-one (2).     

MS/MS profiling of taxoids from the needles of Taxus wallichiana

Ammonium cationisation has been used for taxoid profiling of partially purified methanolic extracts of needles of Taxus wallichiana growing in different regions of the Himalayas (Kashmir, Himachal Pradesh, UP Hills, Darjeeling, Sikkim and Arunachal Pradesh) by electrospray ionisation tandem mass spectrometry (MS/MS). The MS/MS spectra of the [M + NH4]+ or [M + H]+ ions gave structurally diagnostic fragment ions which revealed information about the taxane skeleton as well as the number and nature of the substituents. The rearranged 11(15-->1)-abeo-taxanes showed a characteristic elimination of the hydroxyisopropyl group with an acetoxy/benzoyloxy group from C-9. The identification of the taxoids was achieved by comparison of the MS/MS spectra with those of authentic taxoids or was based on biogenetic grounds. The results were corroborated by liquid chromatography-MS analysis. Out of the 50 taxoids identified, 21 belonged to the rearranged class. The presence of paclitaxel in the samples from four regions was confirmed: the study also revealed the occurrence of several basic taxoids in these samples. MS/MS profiling by electrospray ionisation was shown to be a fast and reliable technique for the analysis of taxoid samples.     

Seasonal changes in the concentrations of four taxoids in Taxus baccata L. during the autumn-spring period.

The concentrations of four common taxoids: baccatin III, paclitaxel, cephalomannine and 10-deacetylbaccatin III (10-DAB III) were measured in fresh needles and stems of Taxus baccata L. during the late autumn-spring period (November'96-April'97) which has not been investigated to date in this species. Baccatin III, paclitaxel and 10-DAB III were present on the surface of the twigs in concentrations of 8-26 micrograms/1000 g (fresh weight). Changes in the levels of baccatin III and paclitaxel inside the needles and stems showed similar trends over the investigated period. From November to March the total level of taxoids differed between the needles and stems, and were the same only in April. Total levels in fresh needles were stable from December to March. The highest concentrations of 10-DAB III in the whole analysed period in fresh stems were measured, as well as in the fresh needles except for samples collected in November and December when the levels of cephalomannine were higher. The concentrations of paclitaxel were usually the lowest. These results confirm that epigenetic factors--date of collection (and thus phyllogenesis) and kind of plant tissue--determine taxoid levels during the late autumn-spring period in T. baccata. The opposite patterns of changes for 10-DAB III and cephalomannine, especially in the fresh needles, suggest a possible role for 10-DAB III in the biosynthetic pathway to cephalomannine, a less polar taxoid with a side-chain at position C-13. As well, owing to the thermolability of taxoids, the influence of low temperatures in December and January could explain the highest observed concentrations of 10-DAB III in the fresh stems and needles, respectively.     

红豆杉采穗圃营建技术

红豆杉是提取紫杉醇 (Taxol)等有效抗癌药物及其前体的主要原料 ,其人工原料林的培育是目前获得原料最简单、最经济的途径 ,采穗圃是提供原料林繁殖材料的基础。文章从苗木培育、圃地选择、造林技术等方面介绍了红豆杉采穗圃的营建技术。并对在丽江、漕涧、昆明和马关等地建立的红豆杉采穗圃的穗条产量及发展前景进行了分析     

Neutral taxoids from Taxus cuspidata as modulators of multidrug-resistant tumor cells

Two taxoids, taxinine NN-7 (1) and 3,11-cyclotaxinine NN-2 (2), were isolated from the neutral fraction of the EtOAc extract of a mixture of needles and young stems of Taxus cuspidata. The structures were determined by spectroscopic analysis. Both compounds showed some activity as modulators of multidrug-resistant tumor cells.     

改进的HPLC法测定红豆杉植物和细胞培养物中紫杉醇的含量

紫杉醇 (Ｔａｘｏｌ)是一种新型的抗癌药物。由于紫杉醇在红豆杉属 (ＴａｘｕｓＬ .)植物中的含量很低 ,而且运用植物细胞培养技术生产紫杉醇仍处实验阶段 ,因此 ,对于紫杉醇含量甚微的样品 ,寻找一种精确、灵敏、快速的检测方法就显得尤为重要。本实验采用改进的ＨＰＬＣ法对南方红豆杉〔Ｔａｘｕｓｃｈｉｎｅｎｓｉｓｖａｒ.ｍａｉｒｅｉ (Ｌｅｍｅ啨ｅｔＬ啨ｖｌ.)ＣｈｅｎｇｅｔＬ .Ｋ .Ｆｕ〕枝和叶 ,以及中国红豆杉〔Ｔａｘｕｓｃｈｉｎｅｎｓｉｓ (Ｐｉｌｇｅｒ)Ｒｅｈｄ .〕细胞培养物中的紫杉醇含量进行了测定。1　实验方法1 1　实…     

Some factors affecting growth and survival ofRhizobium spp. in soil-peat cultures

Summary The growth and survival of rhizobium were studied in neutralized and sterilized soil-peat cultures containing alder bog peat, old moss peat, young reed peat, or young moss peat enriched with lucerne meal and sucrose. Although all these media proved to be excellent carriers for rhizobium, old moss peat from the 0–20 cm layer was less favourable than old moss peat from the 20–40 and 40–60 cm layer, while young moss peat proved to be the least satisfactory type of peat. A low storage temperature is always beneficial for the survival of rhizobia. Neutralization with CaCO₃ is to be preferred to that with CaCO₃+KH₂PO₄. Neutralization with NH₄OH exerted a detrimental effect. Much higher numbers of rhizobium were found in sterilized than in unsterilized soil-peat cultures. An antagonistic bacillus, isolated from peat, exerted a marked growth depression on rhizobium when both organisms were inoculated in sterilized soil-peat or in quartz sand media. Sterilization of the media permitted a rapid growth of the rhizobia and favoured their viability during storage, especially in autoclaved media containing nutrients. For the rhizobium ofLotonus bainesii sterilization of the peat proved essential for good growth. A harmful effect on the numbers of rhizobia was noted during the first week after the inoculation of the soil-peat mixtures when autoclaving had been carried out for 5 hours. This harmful effect proved, however, to be of a temporary nature.