滇龙胆中萜类物质积累的动态变化

滇龙胆（Gentiana rigescens）为传统中药材。采用单因素方差分析比较不同生长季节滇龙胆的根部及茎叶部位龙胆苦苷、獐牙菜苦苷及当药苷含量的动态变化。结果表明,在不同生长季节,滇龙胆的根部与茎叶部位3种有效成分的含量具明显差异。龙胆苦苷主要积累于根部;獐牙菜苦苷、当药苷主要积累于茎叶部位。相关性分析表明,龙胆苦苷含量受气候因子的影响,月平均温度与茎叶部位龙胆苦苷含量呈极显著负相关（R=-0.57,P〈0.01）,月降水量与根部、茎叶部位龙胆苦苷含量呈显著（R=-0.48,P〈0.05）或极显著（R=-0.74,P〈0.01）负相关;根中当药苷含量与獐牙菜苦苷含量呈极显著正相关（R=0.62,P〈0.01）,茎叶部位獐牙菜苦苷含量与当药苷含量呈显著正相关（R=0.38,P〈0.05）。研究结果表明,滇龙胆中龙胆苦苷含量受降水量和温度的影响;龙胆苦苷、獐牙菜苦苷及当药苷的含量变动具相关性;9-11月较适宜滇龙胆药材的采收。     

野生坚龙胆及其组培苗中龙胆苦苷的含量分析

利用含有α-萘乙酸(NAA)、6-苄氨基嘌呤(6-BA)和激动素(KT)等激素的MS固体培养基,对野生坚龙胆进行组培苗诱导培养。同时,应用高效液相色谱技术对野生坚龙胆和其组培苗的根、茎和叶中的龙胆苦苷进行含量分析和比较研究。结果发现,野生坚龙胆中的龙胆苦苷主要储存于根部,而组培坚龙胆中龙胆苦苷在根中的含量甚微,主要集中在茎、叶部位,且在出根初期组培坚龙胆叶中的龙胆苦苷含量近似于或略大于野生坚龙胆根中的含量。研究结果提示,坚龙胆中的绿色组织是龙胆苦苷合成的部位,这些部位同时具有龙胆苦苷的储藏功能。     

条叶龙胆根培养物中龙胆苦苷的产生和含量

条对龙胆愈伤组织中龙胆苦苷含量较低,根的分化可以提高龙胆苦苷的含量。培养的离休根中龙胆苦苷的含量则更高。随着继代次数的增加,愈伤组织中龙胆苦苷含量下降快,而分化根的愈伤组织和离体培养根中龙胆苦苷含量下降较慢。在愈伤组织的液体培养中,1/2MS培养基附加低浓度的植物激素,龙胆苦苷含量有所提高。植物激素配比促进愈伤组织中分化根的形成,也促进龙胆苦苷的产生;但促进愈伤组织的生长时,不利于龙胆苦苷产生。在离体根培养中,添加 1mg/L的金雀花碱,促进龙胆苦苷的产生,含量可达1.48％,明显高于愈伤组织(0.52％)和分化根的愈伤组织(0.65％),也高于试管苗根的龙胆苦苷含量(1.01％)。     

栽培条叶龙胆根中龙胆苦苷含量差异的研究

采用高效液相色谱法,测定栽培条叶龙胆根中龙胆苦苷的含量,结果表明:花末期(9月3日)龙胆苦苷含量高于果期(9月18日)和枯萎期(10月10日);同一根系中二龄根的含量显著高于一龄根;有性后代个体之间龙胆苦苷含量差异显著,对条叶龙胆进行高含量育种研究是可行的。     

栽培措施对龙胆产量及龙胆苦苷类成分含量的影响

为给龙胆药材生产提供栽培技术,在不同时间、以不同密度、分不同种苗等级以及在不同的前茬作物地块上移栽粗糙龙胆,秋季采用五点取样法测定产量,采用HPLC测定龙胆苦苷类成分含量。结果表明秋栽、一级种苗移栽、前茬作物为玉米,密度为125株/m²龙胆产量高,且龙胆苦苷含量都超过10.8%,但密度低龙胆有效成分含量高。秋栽、采用一级种苗移栽、轮作、移栽密度为125株/m²可达到优质高产的目标。     

栽培藏药材麻花艽中四种苦苷类成分含量的季节性变化

采用高效液相色谱法,测定了栽培藏药材麻花艽根中龙胆苦苷、落干酸、獐牙菜苦苷和獐牙菜苷四种苦苷类成分的含量及其在不同生长期的动态变化。结果表明,四种苦苷类成分随植物的发育节律而波动。龙胆苦苷的含量是评价药材质量的重要指标。龙胆苦苷的含量虽然在7月有个积累的高峰期,但7月为花期,从资源可持续利用的角度考虑,不宜定为采收期,到9月含量又有所增加,故而确定栽培藏药麻花艽根的适宜采收期应在9~10月之间。     

滇龙胆不同部位裂环烯醚萜类物质含量比较分析

采用高效液相色谱法,对云南临沧云县滇龙胆不同部位龙胆苦苷、獐牙菜苦苷、当药苷含量进行分析.结果显示:(1)龙胆苦苷、獐牙菜苦苷、当药苷在滇龙胆根、茎、叶、花中均有分布;龙胆苦苷、獐牙菜苦苷在根部含量较高,分别为(35.88±5.89)mg/g和(1.35±0.33)mg/g;当药苷在花部含量最高,为(0.97±0.24)mg/g.(2)不同部位有效成分间具有显著(P<0.05)或极显著(P<0.01)的相关性.(3)相同海拔条件下,不同栽培方式下滇龙胆根部龙胆苦苷含量差异不显著(P>0.05),但茎部、叶部獐牙菜苦苷含量差异显著(P<0.05).     

龙胆酵素的发酵工艺优化及其生化功效研究

以龙胆草为发酵底物,龙胆苦苷为评价指标,采用正交实验优化龙胆酵素的发酵工艺,用高效液相色谱(HPLC)分析龙胆酵素中龙胆苦苷含量,并评估其生化功效。结果表明,最优龙胆酵素发酵工艺为菌株组合酿酒酵母加植物乳杆菌1∶1、接种量10%、发酵温度30℃、发酵时间72 h。在此优化工艺条件下,发酵液龙胆苦苷含量达到(1 823±21)μg/mL,其透明质酸酶抑制率、DPPH、·OH和O2-·自由基的清除能力分别达到89.2%、77.5%、70.2%和74.1%,表明该工艺的发酵液具有很好的抗敏和自由基清除功效。     

响应面法优化线叶龙胆中龙胆苦苷提取工艺

采用响应面法优化乙醇热回流提取线叶龙胆中龙胆苦苷的提取工艺。在单因素试验基础上,选择乙醇浓度、料液比、提取时间为自变量,以龙胆苦苷提取率为响应值,进行Box-Behnken中心组合实验设计,采用响应面法(RSM)评估其对龙胆苦苷提取率的影响。在乙醇浓度71%,液料比34:1,提取时间83min时,提取率达4.52%。     

藏药提宗龙胆和线叶龙胆花中四种苦苷类成分的HPLC测定

应用HPLC分析方法同时测定藏药提宗龙胆和线叶龙胆两种植物花中落干酸、獐牙菜苦苷、龙胆苦苷、獐牙菜苷4种苦苷类成分的含量.采用Econosphere C18色谱柱(250×4.6 mm,5 μm),以甲醇-0.5%乙酸为流动相进行梯度洗脱,流速为1.0 mL/min;检测波长为245 nm.结果表明,除提宗龙胆中未检出獐牙菜苦苷外,其它成分均在两种植物中存在,但含量存在一定的差异.     

板栗种子发育期间ABA等生理指标与脱水耐性的相关性研究

对板栗种子发育期间胚轴和子叶中部分生理指标的变化以及它们与板栗种子脱水耐性的相关性进行研究.结果表明:随着板栗种子不断发育,在花后80 d胚轴和子叶中ABA、淀粉、可溶性蛋白质量分数同步达到最大值,可溶性糖质量分数达到最低,此时板栗种子的脱水耐性最强,可确定为板栗的最佳采收期.另外,通过相关分析可知,板栗种子在发育期间...     

Gas exchange and leaf metabolism of irrigated maize at different growth stages

Abstract

Net ecosystem exchange (NEE), leaf gas exchange and biochemical traits were investigated in an irrigated maize crop grown under Mediterranean conditions. Sub-optimal irrigation water supply determined a drought stress during the early vegetative growth stage (45–49 days after swing) that decreased NEE. Drought, in the late vegetative stage, also caused a reduction of leaf gas exchange. In the latter period, proline, glycine and serine, as well as sucrose leaf contents increased, while starch, proteins and glucose contents decreased. In the early reproductive stage, the crop experienced a longer dry spell that induced a reduction in canopy as well as in leaf gas exchanges, while protein and free amino acid contents decreased with respect to the late vegetative stage. Both ecophysiological and biochemical data demonstrate a good capacity of cultivar Pioneer PR32D99 to endure the environmental stress, related to Mediterranean summer drought, leading to an elevated dry matter yield at harvest. Photosynthetic apparatus appeared fairly resistant to soil water shortage due likely to the increased leaf content of organic solutes, such as amino acids and soluble sugars.     

Cell wall biochemistry and biomechanics of harvested white asparagus shoots as affected by temperature

The effects of temperature on the dynamics of changes in shoot mechanical properties, cell wall components, relevant soluble sugars and respiration activity of harvested white asparagus spears were investigated during a 7-day storage period. All functional cell wall components of asparagus spears increased closely temperature dependent. The content of soluble glucose declined with a similar temporal dynamics and to a comparable degree, indicating a major carbon flow of this storage sugar into cell walls (60–70%). Irrespective of temperature, the contents of stored soluble fructose and sucrose remained more or less constant. Lower temperatures reduced cell wall development but do not significantly affect the relative carbon flow from storage sugars into cell walls or maintenance respiration. Compared with cell walls, maintenance respiration is by far the smaller carbon sink in stored asparagus spears. Temperature differentially affects the absolute amount and the relative contribution of the different cell wall components and the temporal dynamics of changes in structural carbohydrate and lignin content. At higher temperatures, secondary cell wall thickening resulted mainly from a large increase in cellulose content. The pronounced increase in the fractions of cellulose and especially lignin may stress the important role of lignin in cell wall strengthening. While the fraction of cell wall proteins decreased, those of hemicellulose and the pectic components were not influenced.     

Determination of gentiopicroside contents during somatic embryogenesis in Gentiana straminea Maxim

A protocol for regeneration of Gentiana straminea Maxim recently established in our laboratory, somatic embryogenesis was obtained from its leaf derived calli. The gentiopicroside contents of embryogenic calli, globular-, heart-, torpedo-, and cotyledon-shaped embryoids as well as regenerated plantlets were determined by high-performance liquid chromatography. Gentiopicroside was detectable in all materials tested. Embryogenic calli showed the lowest gentiopicroside content. The changes of gentiopicroside contents were not significant (P < 0.05) with the development of somatic embryos. The highest gentiopicroside content (30.7 mg g^?1 dry weight) was achieved in regenerated plantlets. The contents of gentiopicroside were not significant (P < 0.05) differences between control plants and embryogenic calli, different stages of somatic embryos and regenerated plantlets. This protocol could be employed for producing gentiopicroside or other medicinal compounds.     

铁皮石斛醇溶性浸出物和六类物质的动态变化研究

为了解不同生长期铁皮石斛(Dendrobium officinale)化学成分的变化,对茎、叶醇溶性浸出物、多酚、黄酮、三萜类、有机酸、氨基酸、糖含量进行了测定。结果表明,从2015年9月至2016年9月,茎的醇溶性浸出物总量及六类物质含量呈现先下降后上升的变化趋势,在春末夏初时达到最低,而叶片中各成分的变化未体现一致性规律。六类物质中以小分子的糖含量最高,其次是三萜类和有机酸。茎的醇溶性浸出物总量与多糖含量呈显著负相关;而叶的相关性不显著。这些为评估铁皮石斛质量和确定采收期提供科学依据。     

Quantitative and qualitative variations in the glycoproteins in the chick embryo brain

Sugar content was examined in soluble and insoluble glycoproteins extracted from the chick embryo brain at different developmental stages. The content of hexosamines and uronic acids in the soluble fraction is higher during the whole period examined. The difference between the two fractions reaches a maximum at the 15th day. The insoluble fraction shows the highest content of sialic acid and fucose in comparison with the soluble one, especially toward hatching. The sialic acid/fucose ratio shows a different pattern in the two fractions examined, particularly in the soluble glycoproteins. The patterns of sialic acid and fucose indicate that quantitative and qualitative developmental changes occur in the soluble and insoluble glycoproteins. All sugars examined show significant changes on the 15th day, suggesting that this stage may represent a critical period in the development of the chick embryo brain.     

两种沙生植物抗旱生理指标的比较研究

以沙坡头地区自然生长和人工灌溉条件下的沙冬青（Ａｍｍｏｐｉｐｔａｎｔｈｕｓ ｍｏｎｇｏｌｉｃｕｓ）和柠条（Ｃａｒａｇａｎａ ｋｏｒｓｈｉｎｓｋｉｉ）为材料,对它们部分抗旱生理指标的变化进行了研究,结果表明,沙冬青对干办迫最敏感,这些生理指标随着个体发育阶段的不同变化,并具种间差异性。可溶性糖和游离氨基酸（特别是Ｐｒｏ）在干旱环境植物中均有较高含量,沙冬青有较高的热值,类黄酮水平未见差异性变化。     

汶川大地震灾后不同滑坡体上柏木体内非结构性碳水化合物的特性

"5.12"汶川大地震不仅直接摧毁森林17.3万hm2,还通过对土壤和林内生境的剧烈改变对现存森林造成潜在威胁。以地震重灾区北川的主要分布树种柏木为研究对象,在2009年6月初(夏初)和10月初(秋季)两个时期,对不同类型柏木林的叶、枝、根可溶性糖和淀粉含量进行测定分析,旨在认识震后初期柏木对逆境胁迫的生理响应,为研究大地震对植物体内碳水化合物的影响和对逆境的适应性提供科学依据。结果表明:地震对柏木体内碳水化合物的含量有较大影响,总体表现为严重滑坡类型具有较高的可溶性糖含量,较低的根系淀粉含量。夏初严重滑坡类型柏木叶、枝、根可溶性糖含量分别为(11.44±1.08)%、(4.64±0.42)%、(5.48±0.51)%。就不同器官而言,可溶性糖含量叶>根>枝,淀粉含量叶>枝>根;夏初碳水化合物含量均高于秋季,且仅叶片可溶性糖和淀粉含量在不同季节存在显著性差异(P<0.05),说明柏木叶片对地震反应最为敏感。地震带来的灾害如山体滑坡等对植物的生理活动产生巨大影响,不利于林木生长。