酯

RESULTS: With the increasing doses of betulin, the inhibition rate of EC109 cell growth was increased, and their morphological characteristics were changed significamtly.

结果： 白桦酯醇作用于食管癌细胞EC109后，EC109细胞形态发生明显改变，细胞抑制率随白桦酯醇浓度的增高而增高，呈现剂量依赖关系。

Analyzing the relations among betulin content and growth status, geographical location and climatic factors, it was found that the effect of growth status on betulin content was not significant, and betulin content was not only affected by self-provenance and heredity background but also by geographical location and climatic factor.

进一步分析可得，同龄树种的生长状况对白桦酯醇的含量影响不显著；而白桦酯醇的含量不仅受自身种源及遗传背景的影响，同时也受到其所处地理位置和气候因素的影响，即属于基因与环境互作的表现性状。

In this thesis betulin was purified by recrystallization with chloroform and methanol mixture, and orthogonal design had been taken to optimize the conditions of recrystallization including the volume and ratio of chloroform and methanol mixtures.

在白桦酯醇的纯化方面目前比较成熟的方法是氯仿+甲醇混合溶剂重结晶来纯化白桦酯醇，本文通过正交设计，得到最优化的溶剂比例和用量。

To understand the difference of the betulin content in different parts and provenances in Betula platyphylla Suk., the methods to extract betulin were selected, and an accurate HPLC method to detect betulin content was used.

以白桦为研究材料，在白桦酯醇提取方法的选择下，采用高效液相色谱仪分析了白桦不同部位和种源间白桦酯醇含量的变化。

BACKGROUND ＆ AIM: Betulin is an important triterpene. We investigated the antitumor activity of betulin, extracted from the bark of silver birch.

背景与目的：白桦酯醇是一种重要的三萜类生物活性分子，本文从白桦树皮中提取获得白桦酯醇纯品，然后研究该生物活性分子抑制食管癌细胞的活性。

In the forth chapter, betulin was oxidized by Jones oxidation in step 1 and converted to betulonic acid, then betulonic acid was reduced by sodium borohydride in step 2 and converted to betulinic acid.

第四章使用琼氏氧化剂氧化白桦酯醇，硼氢化钠还原制得白桦酯酸。

Our strong products are: Rhodiola rosea extract, Luteolin, Chamomile extract, Apple extract, Betulin, Betulinic acid, Red wine P.E., Bamboo leaf extract, etc.

公司核心产品有红景天提取物，木犀草素，洋甘菊提取物，苹果提取物，红酒提取物，白桦酯醇，白桦酯酸，竹叶提取物等。

Betulin, extraction, solubility, betulinic acid, derivative, synthesis

关键字或关键词组：白桦酯醇，提取，溶解度，白桦酯酸，衍生物，合成

Components were identified which represented 85.1% of the total essential oil by the silica gel column separately.Conclusion 10 components were identified which included Bicyclo (6,3,0) undeca-dien-3-one, 5,5-dimethyl ect. of the essential oil from Angelica acutiloba Kitag were analyzed for the first time.

结果超临界CO2萃取物为黄棕色油状物，得率为0.9%，用GC-MS联用技术从中鉴定出亚油酸乙酯、5，5-二甲基-双环（6，3，0）-1，7-十一烯-3-酮等30种成分，占挥发油总含量65.66%；萃取物经硅胶柱色谱分离纯化，从中鉴定出十八酸乙酯等11种成分，占总含量的85.1%。

Components were identified which represented 65.66% of the total essential oil includding 9.12-octadecadienoic acid, ethyl ester and ect. 11 components were identified which represented 85.1% of the total essential oil by the silica gel column separately.conclusion 10 components were identified which included bicyclo (6,3,0) undeca-dien-3-one, 5,5-dimethyl ect.

结果超临界co2萃取物为黄棕色油状物，得率为0.9%，用gc-ms联用技术从中鉴定出亚油酸乙酯、5，5-二甲基-双环（6，3，0）-1，7-十一烯-3-酮等30种成分，占挥发油总含量65.66%；萃取物经硅胶柱色谱分离纯化，从中鉴定出十八酸乙酯等11种成分，占总含量的85.1%。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。