攀枝花苏铁叶中的一个新黄酮碳甙

从攀枝花苏铁(Cycas panzhihuaensis L. Zhou et S. Y. Yang)叶中分离出6个化合物,其中1个为新黄酮碳甙,命名为攀枝花苏铁甙(1),其结构通过波谱解析和化学降解得以确定.其余化合物分别鉴定为2,3-二氢偏柏黄酮(2)、 5,5″,7,7″,4′,4-六羟基-(2′,8″)-双黄酮(3)、香草酸(4)、β-谷甾醇(5)和胡萝卜甙(6).     

三叶崖爬藤中的新黄酮碳甙

从三叶崖爬藤（Tetrastigma hemsleyanum Diels et Gilg)的95%乙醇提取物中分离得到3个黄酮碳甙,经化学方法和光谱分析鉴定为：5,7,4′-三羟基黄酮-6-α-L-吡喃鼠李糖（1-4）-α-L-吡喃阿拉伯糖甙（1）,5,7,4′-三羟基黄酮-8-α-L-吡喃鼠李糖（1-4）-α-L-吡喃阿拉伯糖甙（2）,5,7,4′-三羟基黄酮-6,8-二-C-β-D-吡喃葡萄糖甙（3）,1和2为新化合物,分别命名为崖爬藤甙和异崖爬藤甙。     

三叶崖爬藤中的新黄酮碳甙

从三叶崖爬藤(Tetrastigma hemsleyanum Diels et Gilg.)的95%乙醇提取物中分离得到3个黄酮碳甙,经化学方法和光谱分析鉴定为:5,7,4′-三羟基黄酮-6-α-L-吡喃鼠李糖(1-4)-α-L-吡喃阿拉伯糖甙(1),5,7,4′-三羟基黄酮-8-α-L-吡喃鼠李糖(1-4)-α-L-吡喃阿拉伯糖甙(2),5,7,4′-三羟基黄酮-6,8-二-C-β-D-吡喃葡萄糖甙(3),1和2为新化合物,分别命名为崖爬藤甙和异崖爬藤甙.     

怒茶素--怒江山茶的一个新黄酮甙

用葡聚糖凝胶和树脂层析技术从云南省昆明地区产怒江山茶（Ｃａｍｅｌｌｉａ ｓａｌｕｅｎｅｎｓｉｓ Ｓｔａｐｆ ｅｘ Ｂｅａｎ）的鲜叶中分离到１１个酚类化合物,其中１０个分别鉴定为已知的槲皮素类黄酮化合物及原花色素类化合物。另１个为新的黄酮甙,经光谱与化学方法测定,其化学结构为槲皮素－３－Ｏ－β－Ｄ－木吡喃糖基（１→２）－α－Ｌ－鼠李吡喃糖基（１→６）－β－Ｄ－葡萄吡喃糖甙,命名为怒茶素。     

石山苏铁和攀枝花苏铁杂交育种试验(简报)

以石山苏铁Cycas sexseminifera为父本,攀枝花苏铁C.panzhihuaensis为母本开展人工授粉,成功获得杂交种子并繁育成苗。结果表明,石山苏铁与攀枝花苏铁可以进行种间杂交,但传粉过程需要传粉者。     

圆穗蓼中的新黄酮甙成分

从圆穗蓼（Ｐｏｌｙｇｏｎｕｍ ｓｐｈａｅｒｏｓｔａｃｈｙｕｍ Ｍｅｉｓｎ．）中分离得到２个新黄酮甙,经光谱分析和化学方法鉴定为：３＇－羟基－５,４＇－二甲氧基－６,７－二氧亚甲基黄酮－３－Ｏ－「β－Ｄ－吡喃木糖基（１→６）」－β－Ｄ－吡喃葡萄糖甙⑴和５,４＇－二甲氧基－３＇－异丙烯基乙酰基－６,７－二氧亚甲基黄酮－３－Ｏ－「β－Ｄ－吡喃木糖基（１→６）－β－Ｄ－吡喃葡萄糖甙⑵,分别命名为圆穗蓼素Ａ     

攀枝花苏铁种群生态地理分布、分布格局及采挖历史的研究

 对攀枝花苏铁(Cycas panzhihuaensis)种群的地理分布、数量特征、空间分布格局和毁坏历史进行了野外调查和研究。结果表明：攀枝花苏铁种群的自然栖息地是相互隔离和片断化的。已发现的13个自然种群中,8个分布在金沙江河谷,5个种群分布在金沙江支流河谷;最大的种群位于攀枝花市郊,占有面积约3.80km2。79年以来的商业采挖使8个种群灭绝,种群分布区从30700km2减少到8800km2,种群占有面积从11.50km2减少到6.30km2。3个被研究种群的分布格局为集群分布,以幼苗聚集程度最大,随着年龄的增加,聚集程度逐渐下降。     

银杏叶黄酮甙浸提工艺的研究

对黄酮含量偏低的银杏叶子进行浸提研究,确定浸提剂为50％～60％乙醇水溶液,液固比为8:1～6:1,浸提温度为60～70℃,浸提时间3～1h,两次。黄酮的浸提率在85％以上;选用A-1和A-2型树脂混合吸附,得到银杏叶提取物产品,黄酮含量26％～31％,得率为1.6％～1.9％。该工艺已用于中试生产,成本较低。     

碳谱在甙结构测定中的应用

本文以齐墩果烷型五环三萜皂甙为例,较为详细地总结归纳了~(13)C-NMR谱在糖的数目,构型、构象、连结位置以及糖链数目等方面的应用规律,以及~(13)C-NMR谱在甙键稳定性、糖的连接顺序等方面的研究概况。     

高效液相色谱法分析测定越桔果渣中的黄酮甙元

采用高效液相色谱法对越桔果渣中黄酮甙元进行定性和定量分析.用甲醇和水（60：40）以0.8 mL/min流速进行洗脱,368 nm波长检测越桔果渣水解液中黄酮类成分并测定其含量.结果：越桔果渣中黄酮甙元主要有杨梅素和槲皮素,其含量分别为：0.0206%和0.0686%.该方法测定样品简单易行,分离效果佳,灵敏度高,重现性好,结果准确可靠.     

Karyotype Analysis of Cycas panzhihuaensis L. Zhou et S. Y. Yang

This paper reports chromosome number and karyotype analysis of Cycas panzhihuaensis endemic to China. The material was collected from Dukou, Sichuan. It is a diploid species, with 2n=22=2m+4sm+4st+l2t. The karyotype of Cycas panzhihuaensis is different from that of the other species of the genus Cycas, which was known to be 2n=4m+8st+10t. The former is a new karyotype in the genus. The authors briefly discuss karyotype evolution of the genus Cycas in this papar.     

Pollination Biology of Cycas panzhihuaensis L. Zhou et S.Y.Yang

The population of cone-bearing cycad, Cycas panzhihuaensis L. Zhou et S. Y. Yang, was male-biased. Although the number of male individuals was almost equal to that of female individuals, the clonal and cone production of male individuals was 1.31 and 2.21 times as much as that of female individuals respectively. The sequence of pollen shedding was from the base to the top of the cone and microsporophyll. The peak of daily pollen shedding occurred at noon and in the afternoon. The airborne pollen concentration decreased quickly within 2.55 m and finally maintained at a low level along with the distance from emitting male cone. The megastrobilus was transformed into a receptive state at the beginning of pollination due to the regular morphological changes of megasporophylls. Two kinds of ants and one kind of cockroaches were found to be active within the megas- trobili during pollination, albeit causing no tissue damage. The microstrobili gave off a strong odor of fennel that could dispel all the insects nearby. The sterile foliar structure of the megasporophyll was able to secret aqueous droplets at dawn which might function as transporting adhered pollen grains by dislodging and accumulating them on or near micropyles during the process of droplets falling. Resuits from field observation showed that pollination of C. panzhihuaensis might be accomplished by different pollinators. Pollen grains were firstly wind-transported from microstrobili to megastrobili and then insects and secreted droplets on the megasporophyll either directly or indirectly carried the pollen grains to ovules within a megastrobilus. However, insects might play as a subsidiary pollinator due to the preferential concentration of airborne pollen grains transported to the megasporophylls.     

Biological Properties,Trunk Anatomy and Growth Patterns of Cycas panzhihuaensis

Cycas panzhihuaensis L. Zhou et S. Y. Yang is a rare and endangered Cycad that grows in dry-hot valley of Jinsha River. The biological properties, trunk anatomy and growth patterns were studied by field investigation and location observation. The results showed as follows: The sex ratio of cones was strongly male based on reproductive episode. There were no significant sexual differences in leaf number, leaf size, trunk size and ramet number. More than 70% of the adult plants produce ramets, with a mean number of ramets per adult plant of about 2.8. The proportion of individuals with ramets and the number of ramets was positively correlated with trunk height. Maximum mean trunk diameter and mean number of leaves were reached when the plant reached 30--40 cm tall. Further increase of leaf width ceased when the plant reached 5 years old. Leaf reached its maximum length when the trunk was 10 cm tall. Growth units of trunk showed a linear relationship with height. The estimated age could be obtained by counting growth units of the trunk. The survival curve of leaves was well described by Deevey type Ⅰ . The survival time of many leaves was two growth units. The rate of leaf mortality abruptly increased after two growth units. Few leaves could survive five units.     

A new species of Cycas (Cycadaceae) from Karnataka,India

Cycas swamyi Singh & Radha, sp. nov. (Cycadaceae) is described and illustrated from Karnataka, India. This new species has been confused with Cycas circinalis L., which is found in the Western Ghats. However, on the basis of its habit, characteristic isotomous‐type dichotomous branching, pinnae anatomy, mega‐ and microsporophyll morphology and seed anatomy, it has been segregated from C. circinalis and is described here as a new species. The distribution and conservation status are also discussed. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 430–435     

我国苏铁属一新种

我国苏铁属(苏铁种)一新种, 即念珠苏铁。     

Cloning and Expression of a Mannose-Binding Jacalin-Related Lectin from Leaves of Japanese Cycad (Cycas revoluta Thunb.)

Cycad leaf lectin (CRLL), a mannose-recognizing jacalin-related lectin (mJRL), was first cloned as a gymnosperm lectin and expressed. The cDNA sequence of CRLL (DDBJ, accession no. AB198328), coding 291 amino acid residues, has a tandem repeat of about 150 amino acids divided into N- and C-terminal domains as Japanese chestnut mJRL. Sequence alignment showed deletion and insertion of the sequence, and its putative carbohydrate-binding sites showed some differences from other JRLs. PCR analysis showed that this lectin was expressed in the cycad leaf but not in the root or seed. Recombinant CRLL (rCRLL) was expressed in Escherichia coli and purified by affinity chromatography after refolding procedures. Properties of active rCRLL appeared to be almost the same as those of native CRLL.     

仙湖苏铁野生种群的报道

深圳塘朗山分布的仙湖苏铁种群是首次发现的该物种的野生种群,具有极高的研究价值,可填补仙湖苏铁野外研究的空白,但目前已处于濒危状态。笔者对该种群在塘朗山的分布状况以及群落特征作了初步报道．     

苏铁的化学成分研究

对苏铁(Cycas revoluta)的化学成分进行研究,采用多种色谱技术(硅胶、氧化铝和Sephadex LH-20等)从苏铁茎的乙酸乙酯部位分离得到16个化合物,其结构由HR-ESI-MS、1H和13CNMR等波谱学方法鉴定为5,6-去氢柳杉酚(1)、cunningine A (2)、6-羟基-5,6-去氢柳杉酚(3)、6α-羟基-7-氧代弥罗松酚(4)、ligballinol (5)、xanthoxyol (6)、callislignan A (7)、(2R,3R)-bis[(4-hydroxy-3-methoxyphenyl) methyl]-1,4-diacetate (8)、开环异落叶松脂醇(9)、二氢山柰酚(10)、4'-甲基木犀草素(11)、5-methoxypinosylvin (12)、N-benzoylphenyl alaninol(13)、(E,4R)-4-hydroxy-4,5,5-trimethyl-3-(3-oxobut-1-enyl) cyclohex-2-enone (14)、3-hydroxy-5α,6α-epoxy-β-io-none (15)和acuminantin (16)。以上化合物均为首次从苏铁属植物中分离得到,其中化合物13和16为首次以天然产物报道。本研究还首次发现了苏铁属植物中含有松香烷型二萜类(1～4)和芪类(12)化合物。化合物11具有中等的体外α-葡萄糖苷酶抑制活性。