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白桦树皮中桦木醇超临界二氧化碳萃取的研究(英文) 总被引：4，自引：0，他引：4
桦木醇,一种药用五环三萜成分,大量存在于白桦(Betulaplatyphlly)树皮中。白桦树皮于2000年9月采集自黑龙江省塔源林场。超临界流体萃取技术(SFE)是一种新型分离技术,广泛用于药物和天然产物生产。本文研究了利用超临界CO2萃取技术从白桦皮中提取桦木醇的工艺条件,系统分析了携带剂用量、萃取压力和萃取温度等参数对桦木醇提取率的影响。结果表明,最佳的萃取条件为:每克桦树皮粉所用携带剂用量为1.5mL,萃取压力为20Mpa,萃取温度为55C,CO2流量为10kg/h,分离压力和分离温度分别为5.5Mpa和50C。图4参6。 相似文献
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Plant growth regulation effects of triterpenoid saponins 总被引：1，自引：0，他引：1
To investigate structure–activity relations between the sugar chain structures of triterpenoid saponins and their plant growth
regulation effects, several monodesmosidic saponins with betulin as an aglycon were synthesized by chemical and enzymic reactions.
Three triterpenoids (betulin, betulinic acid, oleanolic acid) and synthesized betulin glycosides were submitted to germination
and growth regulation tests on alfalfa seeds. We concluded the following. Betulin had a slight growth inhibitory effect on
alfalfa radicles. Betulin glycosides exhibited stronger effects than betulin, and betulin glycosides with two to four glucose
residues as a sugar moiety had the greatest inhibitory activity. These characteristics of growth inhibitory effects were considerably
different from those of phenolic compounds so far reported. Some betulin glycosides also showed a significant growth regulation
effect on alfalfa hypocotyls. However, hypocotyl growth was less affected than radicle growth for all betulin glycosides.
Among the triterpenoids, betulinic acid had stronger growth inhibitory effects on alfalfa radicles than betulin, suggesting
the importance of the carboxyl group at the C-28 position for the inhibitory effects of lupane-type triterpenoids. On the
other hand, no germination regulation effects on alfalfa seeds were observed for any of the betulin glycosides or triterpenoids
examined.
Received: October 9, 2001 / Accepted: February 15, 2002
Acknowledgments This work was supported in part by a research grant (Development of Highly Functional Materials by Structural Modification
of Carbohydrates) from the Ministry of Agriculture, Forestry, and Fisheries of Japan. We thank Saori Kudo for her assistance
in isolating compounds by chromatography.
Correspondence to:S. Ohara 相似文献
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ZHANGYu-hong YUTao WANGYang 《林业研究》2003,14(3):202-204
Betulin, which is a medicinal pentacyclic triterpene, is abundant in the bark of white birch (Betula platyphlly). The bark of birch was collected at Tayuan Forest Farm of Jiagedaqi, Heilongjiang Province in September 2000. Supercritical fluid extraction (SFE) that is a new separation technology has been used for the processing pharmaceutical and natural products. In this paper, the extraction of betulin from the bark of birch by supercritical CO2 extraction was studied. The authors investigated and analyzed a few parameters such as modifier dosage, extraction pressure and extraction temperature. The optimal extraction conditions showed that the modifier dosage used for per gram bark powder was 1.5 mL, the extraction pressure was at 20 Mpa, and the extraction temperature was at 55 ℃. The velocity of flow of liquid CO2 was at 10 kg/h. The pressure and temperature in separation vessel were at 5.5 Mpa and 50 ℃, respectively. 相似文献
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[目的]探究一氧化氮供体硝普钠(SNP)对白桦悬浮细胞中K~+、Ca~(2+)和白桦酯醇累积的影响及外源K~+、Ca~(2+)与SNP互作对白桦酯醇累积的影响。[方法]利用高效液相色谱法、原子吸收光谱法及比色法分别测定白桦酯醇、K~+及Ca~(2+)含量。[结果]SNP处理对白桦悬浮细胞中K~+、Ca~(2+)的累积存在浓度和时间效应,其中1 mmol·L-1SNP处理12 h时K~+含量最高,是对照组的1.47倍,而Ca~(2+)含量在5 mmol·L-1SNP处理96 h时最高,是对照组的1.50倍。1 mmol·L-1SNP与不同浓度KCl共同处理后,白桦酯醇含量高于单独SNP与KCl处理,其中,SNP与0.1 g·L-1KCl共同处理时,白桦酯醇的积累量最大,是单独SNP处理1.72倍,是单独KCl处理2.33倍。1 mmol·L-1SNP与不同浓度Ca Cl2互作处理后,白桦酯醇含量高于单独SNP与Ca Cl2处理,其中,SNP与0.1 g·L-1Ca Cl2共同处理时,白桦酯醇的积累量最大,是单独SNP处理2.75倍,是单独Ca Cl2处理2.18倍。[结论]SNP处理诱导了白桦悬浮细胞中K~+和Ca~(2+)的合成和白桦酯醇的累积,SNP分别与K~+或Ca~(2+)互作可以更好的促进白桦悬浮细胞中白桦酯醇的累积,同时推测SNP诱导的K~+、Ca~(2+)在一定程度上介导了白桦酯醇的累积。 相似文献
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The ethanol extract and fractions from Coccoloba acrostichoides aerial parts were assayed for in vitro antimicrobial activity. The extract was active against the assayed bacteria while most of the fractions also inhibited fungal growth, especially the n-hexane and EtOAc fractions. The isolated beta-sitosterol and betulin were tested, being the last one active against Fusarium oxysporum. 相似文献
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[目的]优化白桦树皮桦木醇含量高效液相检测方法.[方法]利用均匀试验设计筛选了白桦待分析样品的制备方法,测定了距地面不同高度位置白桦树皮中桦木醇的含量.[结果]在0.5～4.0m高度范围内,距地面1.5m处的白桦树皮中桦木醇的含量最高,为17.56％,距地面4.0m处的白桦树皮中桦木醇的含量最低,为14.51％.整体上,不同高度位置的白桦树皮中桦木醇含量差异不显著.[结论]得到提取桦木醇样品制备的最佳条件:以100％乙醇70℃超声波(40 Hz,150 W)提取白桦树皮样品60 min. 相似文献
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