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1.
Betulin, oleanolic acid, and betulinic acid are naturally occurring pentacyclic triterpenoids that have significant medicinal value. Considerable amounts of these triterpenoids are available in the out... 相似文献
2.
白桦树皮化学组成的研究 总被引:5,自引:0,他引:5
经究了白桦树皮的化学组成,内皮的外皮的灰分、抽提物、木质素、多戊糖、综纤维素和软木脂含量。通过GC、GC-MS对外皮中的两种主要成分软木脂单体和三萜系化合物进行了定性和定量分析。不同径级的三个样品的软木脂脂单体平均含量每公斤外皮(干基,下同)为175g,软木脂单体中以9,10-环氧-18-羟基十八烷酸为主,每公斤外皮为55.1g,占软木脂单体总量的31.5%。可确认的软木脂单体占气相色谱可分谱可分 相似文献
3.
A quantitative HPLC analysis of the major triterpenoids present in an aqueous extract of powdered neem kernels prepared in the traditional manner was undertaken. The study shows that water extracts contain all the principal triterpenoids in neem kernel though the quantities extracted are much less than in the subsequent extraction with methanol. 相似文献
4.
Phytochemical and antimicrobial studies on Drynaria quercifolia 总被引:1,自引:0,他引:1
N. Ramesh M. B. Viswanathan A. Saraswathy K. Balakrishna P. Brindha P. Lakshmanaperumalsamy 《Fitoterapia》2001,72(8):283-936
Friedelin, epifriedelinol, beta-amyrin, beta-sitosterol, beta-sitosterol 3-beta-D-glucopyranoside, and naringin were isolated from the dried rhizome of Drynaria quercifolia. The methanol extract showed broad and concentration-dependent antibacterial activity. 相似文献
5.
分光光度法快速测定灵芝中总三萜含量 总被引:12,自引:0,他引:12
选用熊果酸为对照品,5%香草醛—冰醋酸和高氯酸为显色剂,以分光光度法测定灵芝中总三萜的含量。实验结果表明:在548 nm波长下,标准品在12~53μg范围内,吸光度与含量呈良好的线性关系,在4~45 m in内稳定。该方法操作简便,快速,灵敏度高和重复性好,可用于灵芝及其相关产品的质量控制。 相似文献
6.
[目的]探究血芝液体深层发酵合成三萜类化合物的最佳发酵条件。[方法]先以单因素试验分析碳源、氮源、转速、p H、接种量对血芝液体深层发酵合成三萜类化合物的影响,选取其中3个主要影响因素,采取响应面分析法进一步优化血芝液体深层发酵合成三萜类化合物的最佳工艺条件。[结果]单因素试验结果显示,血芝发酵合成胞内三萜类化合物的最适条件为p H=6,转速为130 r/min,最适碳源为蔗糖,最适氮源为尿素。响应面法优化的发酵条件为3%接种量、30 g/L蔗糖、1.9 g/L尿素,血芝三萜类化合物含量达16.51mg/g。[结论]该研究为血芝活性成分的研究提供实际参考依据。 相似文献
7.
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
8.
Akwasi Ampofo-Yeboah Helet Lambrechts Danie Brink Fletcher Hiten Evans Afriyie-Gyawu 《农业科学与技术》2013,(12):989-999
Oleanolic acid (OA) and ursolic acid (UA) are isomeric tritcrpenes that are difficult to separate chromatographically. Studies have indicated that both OA and UA have antifertility properties in several livestock species, suppressing attainment of puberty, gonad function and gamete production. Being able to determine the presence and quantity of the OA and UA in moringa and pawpaw seeds will allow for calculation of optimal inclusion levels of these acids in animal diets for antifertility-activity. The purpose of the study was thus to quantify the levels of OA and UA in Moringa and pawpaw seed powder by means of ultra-high performance liquid chromatography with electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS). Only OA was detected in moringa seeds at a concentration level of 0.508 p.g/g + 0.032 pg/g dry weight. UA and OA could not be detected in pawpaw seeds used in this study. The presence of OA in moringa seeds suggest that the seeds can be included in tilapia diets as a potential antifertility treatment to control precocious breeding in tilapia culture in small scale farming systems in Sub-Saharan Africa. Further studies are warranted to determine the levels of OA and UA composition in moringa seeds from other parts of the Sub-Saharan Africa (other than Zambia). 相似文献
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