甘草悬浮细胞的玻璃化法超低温保存研究

以甘草悬浮细胞为材料,进行了超低温保存技术的研究。高产黄酮的甘草悬浮细胞是一种极具价值但又难于保存的材料,为解决甘草细胞超低温保存中存在的关键问题,即如何减少渗透压的突然改变对细胞造成损伤,通过优化预培养时间、细胞年龄、预处理时间、脱水时间、洗涤液蔗糖浓度等影响因素,建立了一套适合于甘草悬浮细胞的保存方法。采用改良的2,3,5-氯化三苯基四氮唑(TTC)法检测,此法存活率可达82.9%。将保存后的细胞进行恢复培养,其恢复生长率可达80.4%。     

甘草在水产养殖中的应用

甘草(Glycyrrhiza uralensis Fiseh)因其具有调和诸药的特性, 被誉为“百草之王”, 是我国常见廉价药材, 被应用于水产养殖。其有效成分主要是多糖、甙类、生物碱、有机酸和挥发油等。在水产养殖中, 常见的甘草给药方法包括投喂、灌服、注射、浸泡以及泼洒等, 用于水产动物的免疫调理、病害防治以及其他用途。然而, 甘草在使用过程中也存在着一些问题, 比如药材质量不稳定、使用方法较为粗放、规范化药方较少、命名和描述不够准确等。本文对甘草的渔用价值进行了综述。     

甘草黄酮类化合物对酪氨酸酶单酚酶的抑制

研究了甘草中四种黄酮类化合物甘草甙、异甘草素．葡萄糖芹菜甙、异甘草甙和甘草查耳酮甲对酪氨酸酶单酚酶活性的抑制。结果表明异甘草素-葡萄糖芹菜甙、异甘草甙和甘草查耳酮甲的IC50分别为0．072mM,,0．038mM,0.0258mM,它们都属于竞争性抑制剂,甘草甙没有抑制活性。研究表明,异甘草素．葡萄糖芹菜甙、异甘草甙和甘草查耳酮甲可以作为潜在的美白化妆品添加剂。     

甘草次酸衍生物的合成研究

本文以甘草提取物——甘草酸或甘草次酸为原料,采用化学修饰合成了三种甘草次酸的衍生物——甘草次酸甲酯、乙酰甘草次酸甲酯和硬脂酰甘草次酸甲酯,并初步表征了它们的结构及性质。其中由甘草粗皂苷直接制备甘草次酸甲酯的方法及后两种化合物的合成均为首次报道。     

甘草有效成分的药理作用研究进展

综述了近年来甘草中有效成分甘草酸、甘草次酸、甘草黄酮类物质、甘草多糖的药理活性。     

基于HPLC指纹图谱结合化学计量学的甘草微波制与传统炮制的差异研究

分别建立生甘草、蜜炙甘草、清炒甘草及微波制甘草的HPLC指纹图谱,生甘草和蜜炙甘草均标定了17个共有峰,炒甘草和微波制甘草均标定了14个共有峰,4、5、11号峰为生甘草和蜜炙甘草的特有峰;不同炮制品相对应成分峰面积大小有所不同;混合对照品指认出的5个峰分别为:2号峰芹糖甘草苷,3号峰甘草苷,8号峰异甘草苷,10号峰甘草素,16号峰甘草酸;指纹图谱相似度除样品S5、C1、C5的相似度在0.883～0.900之间外,其余均大于0.914,说明甘草样品经不同方法炮制后总体相对稳定。聚类分析(CA)结果显示,生甘草、蜜炙甘草能够各自聚类,能够明确判别;炒甘草和微波制甘草聚为一类,无法明确判别。主成分分析(PCA)结果显示甘草四种炮制品基本各自聚类,有明显差异,主要差异成分峰为8号峰,是异甘草苷。偏最小二乘-判别分析(PLS-DA)结果显示甘草四种炮制品各自聚类效果良好,但清炒甘草和微波制甘草二者比较集中,结果和CA一致。因此,分别对微波制甘草及清炒甘草、微波制甘草和生甘草、微波制甘草和蜜炙甘草建立正交偏最小二乘-判别分析(OPLS-DA)模型,均具有良好的预测能力。OPLS-DA的差异成分分析变量重要性投影(VIP)结果显示,微波制甘草和生甘草的主要差异色谱峰为2、1、8号色谱峰,微波制甘草和清炒甘草的差异成分峰为7、2、9、15、6、13、17、16、14号色谱峰,微波制甘草和蜜炙甘草的主要差异色谱峰为8、13、7、16号色谱峰。以上研究确定出了甘草经微波加热炮制后与生品、蜜炙品、清炒品的差异成分,实验方法准确度高,重复性好,为现代微波加热炮制方法的可行性提供参考。     

宁夏野生甘草中产甘草黄酮耐盐内生真菌分离及其DPPH自由基清除作用

采用组织分离法,在不含盐及含盐PDA培养基上分离、纯化内生菌,以甘草苷等8种甘草黄酮为对照品,分析发酵产物;DPPH自由基清除法测定清除率。共得到108株内生菌,TLC发现31株可能产甘草黄酮;HPLC-UV发现产甘草苷7株,产异甘草苷3株,产甘草素3株,产甘草查尔酮A3株,产刺甘草查尔酮1株,均为耐盐菌;产甘草苷、异甘草苷、甘草查尔酮A、刺甘草查尔酮的部分菌株有较强DPPH清除率;产甘草苷和异甘草苷的菌株8-5-Y-2活性最强,与甘草总黄酮相当,强于甘草查尔酮A。盐协迫得到产甘草黄酮,且具较强DPPH自由基清除活性的耐盐内生真菌,为资源替代奠定基础。     

甘草花粉超微鉴定及花粉活力、柱头可授性荧光显微镜观察

对甘草的有性生殖特性进行了研究,利用扫描电子显微镜对乌拉尔甘草、光果甘草和胀果甘草花粉的超微结构进行观察,利用荧光显微镜确定乌拉尔甘草的授粉方式、花粉生活力和柱头活性以及授粉后受精时间.结果表明,花粉超微结构为甘草的鉴别提供了一定的形态学依据;甘草的授粉方式属于闭花受精;花粉生活力在每天12:00时最强,去雄后超过4d的柱头已经不具备接受花粉的能力;对授粉后不同时间的雌蕊进行研究得出授粉后6h花粉管进入胚珠进行受精.     

甘草种皮表面微形态特征及其分类意义初探

甘草是重要的资源植物。我国甘草属植物有:乌拉尔甘草(G. uralensis Fisch.)、光果甘草(G. glabra L.)、胀果甘草(G. inflata Bat.)、黄甘草(G. eurycarpa P. C. Li)、粗毛甘草(G. aspera Bat.)、云南甘草(G. yunnanensis Cheng f. et L. K. Tai ex P. C. Li)、刺果甘草(G. pallidiflora Maxim.)和圆果甘草(G. squamulosa Franch.)。甘草的种子大小相似,均为3.0—4.0mm,但形状和颜色差异较大,其中乌拉尔甘草、光果甘     

相同条件下的5种甘草中甘草酸含量的比较研究

通过双波长薄层扫描对同一生长环境下生长时间相同的5种甘草进行了甘草酸含量的分析、比较,并首次分析了采收时间对甘草中甘草酸含量的影响。同时通过HPLC法对刺果甘草进行了甘草酸的定性分析。为甘草的质量评价、采收时间及种间鉴别提供了依据。     

食物、捕食和种间竞争对东方田鼠种群动态的作用

采用2×2×2析因实验设计,在野外围栏条件下,测定食物、捕食和竞争物种黑线姬鼠(Apodemus agrarius)对东方田鼠(Microtus fortis)种群动态作用的格局.食物可利用性、捕食及种间竞争的独立作用对种群最小存活数均具有极显著的效应,除捕食与种间竞争的交互作用接近显著水平外,食物与种间竞争、食物与捕食者以及三者间的交互作用均不显著;三类外部因子对种群补充量的独立作用效应均达到极显著水平,且对种群补充量的作用具有累加效应;食物可利用性、捕食及种间竞争对种群繁殖成体的比例具有极显著的作用;三类外部因子对种群幼体与成体的比例具有极显著的作用.对种群年龄结构而言,与捕食者及种间竞争比较,食物可利用性是相对较弱的影响因子,在任何捕食与种间竞争交互作用条件下,食物的作用均不显著;三类外部因子均能显著地影响东方田鼠的体重增长率,但三者的交互作用对其影响不显著;MANOVA结果表明,捕食对成体存活率的作用最强烈,其次,为食物可利用性,种间竞争的作用最弱,但三者的交互作用效应不显著.对幼体的存活时间,除捕食的作用接近显著水平外,食物可利用性及种间竞争的作用均不显著.结果提供了食物可利用性、捕食和种间竞争对东方田鼠种群动态作用的充分证据,验证了食物、捕食和种间竞争对田鼠类种群动态具有独立或累加效应的总假设.     

叶子花表皮特征的研究及意义

对叶子花（Bougainvillea spectabilis）正常叶和变态叶上气孔密度、气孔指数和保卫细胞大小进行了研究。结果表明：正常叶上表皮的表皮细胞为多边形,垂周壁平直;下表皮的表皮细胞为不规则型,垂周壁浅波状;气孔类型为不规则型。变态叶上表皮没有发现气孔,变态叶下表皮的表皮细胞垂周壁则由浅波形逐渐变为深波形,气孔类型为不规则型和轮列型。随着变态叶的发育,变态叶下表皮的气孔密度降低,气孔指数升高;变态叶保卫细胞的长增大,宽减小。变态叶的平均气孔密度和平均气孔指数明显低于正常叶。正常叶和变态叶的保卫细胞均呈肾形。     

Effects of Single P-Element Insertions on Bristle Number and Viability in Drosophila Melanogaster

Single P-element mutagenesis was used to construct 1094 lines with P[lArB] inserts on all three major chromosomes in an isogenic background previously free of P elements. The effects of insertions on bristle number and on viability were assessed by comparison to 392 control lines. The variance and effects of P-element inserts on bristle number and viability were larger than those inferred from spontaneous mutations. The distributions of effects on bristle number were symmetrical and highly leptokurtic, such that a few inserts with large effects caused most of the increase in variance. The distribution of effects on viability were negatively skewed and platykurtic. On average, the effects of P-element insertions on bristle number were partly recessive and on viability were completely recessive. P-element inserts with large effects on bristle number tended to have reduced viability, but the correlation between the absolute value of the effects on bristle number and on viability was not strong. Fifty P-element inserts tagging quantitative trait loci (QTLs) with large effects on bristle number were mapped cytogenetically. Two P-element-induced scabrous alleles and five extramacrochaetae alleles were generated. Single P-element mutagenesis is a powerful method for identifying QTLs at the level of genetic locus.     

Host selection, development, survival, and reproduction of turnip aphid (Homoptera: Aphididae) on green and red cabbage varieties

Host selection, development, survival, and reproduction of the turnip aphid, Lipaphis erysimi (Kaltenbach), on selected green and red cabbage varieties, Brassicae oleracea L. variety capitata, were studied in the laboratory. Although numbers of alate L. erysimi on different varieties varied generally, more alate adults and nymphs were observed on green than on red varieties on day 3; whereas, these differences were not so significant on day 15. There were no significant differences in alate adults on all six varieties on day 15. Numbers of nymphs and apterous adults of L. erysimi varied among the varieties. When mean numbers of those aphids on green varieties were compared with those on red varieties, the green varieties had more nymphs and apterous adults than those on the red varieties. Developmental durations of L. erysimi nymphs also varied among all varieties, and the nymphs fed on green varieties developed longer than those fed on red varieties. Adult longevities on these cabbage varieties were not significantly different; whereas, the adult fecundities were. Survival rates of L. erysimi varied greatly among all varieties, but there are no significant differences between the green and red varieties. Factors that might affect aphid host selection, growth, longevity, fecundity, and survivorship were discussed.     

The food of young Puffins Fratercula arctica

Although Puffins fed their young on those species of small fish that were most abundant in mid water, there was some evidence of selectivity. Sandeels and Sprats were by far the most important prey species. Rockling and Whiting were also taken but they were less suitable because of their small size and low calorific value respectively. Many of the abundant gadoid and flatfish species were not preyed on to any extent. Some years Puffins on St Kilda fed their young on Whiting but in these years chicks fledged at lower weights than in years when young were fed on Sprats. It is suggested that Puffins on St Kilda were short of the best prey species compared to those on the Isle of May and were forced to feed their young on sub-optimal food.     

虫草成熟子囊壳、子囊与子囊孢子的电镜观察

虫草子囊壳壁为拟薄壁组织,基部与子座菌丝相联,顶端有一孔口,其内无缘丝,中心腔内无侧丝,基部着生的子囊垂直平行排列。子囊顶端中央是乳状突起,围以隆起的环状膜质边缘。成熟时,其顶端乳状突起膨大,膜质边缘也随之翻卷,中央有一小孔。同一子囊壳内子囊顶端发育阶段不同,说明子囊的形成不同步。子囊内含有两条平行的具横隔的子囊孢子。虫草子囊顶端形态结构即不象虫草属模式种蛹虫草,也不象头状虫草,说明子囊顶端的形态结构的种间差异。     

The Microflora and Concentrations of Volatile Fatty Acids in The Rumen of Cattle Fed on Single Component Rations

The composition of the rumen microflora and the volatile fatty acids were examined in cattle free-grazing on grass or stall-fed on hay, grass pellets, oats or dried beet pulp with molasses. Total and viable counts of anaerobic bacteria were highest on the grass feeding, but viable counts as a percentage of total counts were highest when oats or beet pulp with molasses were fed. Counts of cellulolytic bacteria were lowest on these latter 2 diets, and highest on grass or grass pellet diets. Studies of the anaerobic flora showed that the composition in animals fed on grass pellets resembled more that found in animals free-grazing on grass than in those fed on hay. Counts of aerotolerant bacteria were only a small percentage of the total count, but were highest on the hay diet. On this latter diet and on grass-feeding the streptococci (identified as Streptococcus bovis) were predominant, but contrary to expectation, streptococci were found only in small numbers on the oats diet, where coryneform rods were the major type present. Although a period of 4–6 weeks was allowed for the animals to adapt to the feeds, the 2 periods of feeding on oats and dried beet pulp with molasses markedly affected the composition of the rumen flora in the subsequent periods of feeding grass pellets and hay. Ruinen volatile fatty acid analysis showed a propionogenic effect of oats and the highest percentage of butyric acid when beet pulp with molasses was fed. The expected propionogenic effect of grass pellets was not observed.     

黄土高原不同干旱类型区苜蓿草地深层土壤干燥化效应

田间实地测了黄土高原不同干旱类型区不同生长年限苜蓿草地0～1000cm土层土壤湿度,分析和比较了各类苜蓿草地深层土壤干燥化效应特征。结果表明,在半湿润区、半干旱区和半干旱偏旱区,各类苜蓿草地土壤湿度平均值分别为10．84％、7．07％和5．45％,明显低于当地土壤稳定湿度值和荒草地土壤湿度值,土壤水分过耗量分别为540．2、641．1mm和455．0mm,平均土壤干燥化速度分别为61．2、101．9mm/a和99．0mm／a;3种类型区各类苜蓿草地年降水入渗深度分别为187．8、144cm和173cm,降水入渗深度以下深层土壤湿度保持稳定的干燥化状态;土壤干燥化强度随苜蓿草地生长年限延长而加剧,3年生苜蓿草地为中度干燥化强度,土壤干层厚度达到500～760cm,4年生以上苜蓿草地已达到严重干燥化和强烈干燥化强度,土壤干层厚度超过940～1000cm;通过粮草轮作使苜蓿草地土壤湿度恢复到当地土壤稳定湿度分别需要6、11a和18a以上。     

Subgroups of the Cowpea Miscellany: Symbiotic Specificity within Bradyrhizobium spp. for Vigna unguiculata, Phaseolus lunatus, Arachis hypogaea, and Macroptilium atropurpureum

Rhizobia classified as Bradyrhizobium spp. comprise a highly heterogeneous group of bacteria that exhibit differential symbiotic characteristics on hosts in the cowpea miscellany cross-inoculation group. To delineate the degree of specificity exhibited by four legumes in the cowpea miscellany, we tested the symbiotic characteristics of indigenous cowpea bradyrhizobia on cowpea (Vigna unguiculata), siratro (Macroptilium atropurpureum), lima bean (Phaseolus lunatus), and peanut (Arachis hypogaea). The most-probable-number counts of indigenous bradyrhizobia at three sites on Maui, Hawaii, were substantially different on the four hosts: highest on siratro, intermediate on cowpea, and significantly lower on both lima bean and peanut. Bradyrhizobia from single cowpea nodules from the most-probable-number assays were inoculated onto the four hosts. Effectiveness patterns of these rhizobia on cowpea followed a normal distribution but were strikingly different on the other legumes. The effectiveness profiles on siratro and cowpea were similar but not identical. The indigenous cowpea-derived bradyrhizobia were of only moderate effectiveness on siratro and were in all cases lower than the inoculant-quality reference strain. Between 5 and 51% of the bradyrhizobia, depending on site, failed to nodulate peanut, whereas 0 to 32% failed to nodulate lima bean. No significant correlation was observed between the relative effectiveness of the bradyrhizobia on cowpea and their corresponding effectiveness on either lima bean or peanut. At all sites, bradyrhizobia that were ineffective on cowpea but that effectively nodulated lima bean, peanut, or both were found. Eighteen percent or fewer of the bradyrhizobia were as effective on lima bean as the reference inoculant strain; 44% or fewer were as effective on peanut as the reference strain. Only 18% of all cowpea-derived bradyrhizobia tested were able to form N(2)-fixing nodules on both lima bean and peanut. These results indicate the need to measure indigenous bradyrhizobial population characteristics directly with the crop of interest to obtain an accurate assessment of the need to inoculate.     

Spore age and coverslip placement affects germination and post-germination development of Colletotrichum dematium var circinans

Spore suspensions from young (10–14 da; young spores) and old (4 mo; old spores) colonies of PColletotrichum dematium var circinans were placed on slides. Coverslips were left off, placed on in the normal manner, or supported on shims. Slides were placed in moist chambers and incubated in light or dark for up to 48 hrs. Germination and post-germination development were studied. Shimming had some beneficial effect on germination, especially for old spores in dark. In general, more germ-tubes and appressoria were produced on spores under shims than spores with other coverslip treatments. By 48 hrs more old spores under shims germinated, and greater numbers of germ-tubes and appressoria were produced than on other old spores under different coverslip treatments. However, numbers produced were lower than those predicted for comparably treated young spores. Spore age, incubation regime, and placement of coverslips did not affect germ-tube initiation. For all treatments more germ-tubes were initiated from spore tops than bottoms or tips. Fewer germ-tubes were initiated from spore centers than other locations on tops and bottoms, and from both tips than one tip. Approximately 26 % of all appressoria were produced sessile. A higher percentage of sessile appressoria were produced on old spores (80 %) than on young spores (20%).