不同干燥方式对百蕊草中两种黄酮醇苷含量影响

研究不同干燥方法对百蕊草及百蕊草不同部位中槲皮素醇苷和山柰素醇苷含量的影响和百蕊草不同部位中两种黄酮醇苷的含量分布。采用阴干、晒干、105℃杀青后80℃烘干、霉变后80℃烘干4种干燥方式及80℃,60℃,40℃直接烘干3种不同烘干温度处理百蕊草样,并用80℃烘干百蕊草叶、茎、叶、果实、根不同部位样,测定其酸水解液中槲皮素及山柰素含量,计算其两种黄酮醇苷含量。4种不同干燥方式对百蕊草中两种黄酮醇苷含量影响为烘干=晒干 阴干 酶变, ;3种不同烘干温度对百蕊草中两种黄酮醇苷含量影响为：40℃烘干样 80℃烘干样=60℃烘干样。百蕊草不同部位样中山奈素醇苷分布为叶 茎 种子 根;而其槲皮素醇苷分布由高至低则为：茎 叶 种子 根。明确了百蕊草根、茎、叶及种子中槲皮素及山柰素醇苷的分布,其中叶中含量最高,同时确定百蕊草最佳干燥方式为烘干,且80℃及60℃烘干温度均能有效地保持百蕊草中两种黄酮醇苷成分。     

夹竹桃（Nerium indicum）皂甙对鲫鱼（Carassius auratus）幼鱼的影响

为了评价夹竹桃皂甙对非靶标生物的潜在危害,采用半静态法研究了不同浓度(0、5.89、20.12mg·L-1和80.76mg·L-1)的夹竹桃皂甙对鲫鱼幼苗的死亡情况、特定生长率、糖原、蛋白质含量、SOD酶活性和微核率的影响。结果表明,当夹竹桃皂甙处理浓度≤20.12mg·L-1时,处理组的鲫鱼在试验期间无死亡;而在80.76mg·L-1皂甙的处理下,鲫鱼5d后全部死亡。当皂甙染毒浓度达20.12mg·L-1时,随处理时间的增加,特定生长率、糖原和蛋白质含量逐渐下降,而SOD活性先上升后下降;在清水中恢复饲养7d后,鲫鱼幼苗特定生长率和SOD活性受到的抑制作用逐渐减弱,糖原和蛋白含量恢复至与对照组相比无显著差异。此外,微核试验表明夹竹桃皂甙对鲫鱼幼苗的微核率无影响。研究结果表明,夹竹桃皂甙对鲫鱼的毒性属低等毒性且未发现遗传毒性,但高浓度的皂甙能影响鲫鱼幼鱼的正常生理代谢,导致生长受到抑制,严重时可致其死亡。     

New bibenzyl glycosides from leaves of Camellia oleifera Abel. with cytotoxic activities

Studies on the chemical constituents of leaves of Camellia oleifera Abel. led to the isolation of 3 new bibenzyl glycosides. Their structures have been elucidated as 1-(3′,5′-dihydroxy)phenyl-2-(4″-O-β-D-glucopyranosyl)phenylethane (1), 1-(3′,5′-dimethoxy)phenyl-2-(4″-O-β-D-glucopyranosyl)phenylethane (2) and 1-(3′,5′-dimethoxy)phenyl-2-[4″-O-β-D-glucopyranosyl(6→1)-O-α-L-rhamnopyranosyl]phenylethane (3) through spectral studies including HR-ESI-MS, ¹H NMR, ¹³C NMR and 2D NMR experiments. All the above 3 bibenzyl glycosides showed cytotoxic activities to Hela and hep2 cell lines.     

有待进一步开发的植物性杀虫剂——萜类

植物体内的许多萜类化合物对昆虫有多种生物活性，是很有前途的植物性杀虫剂，有待于进一步开发。就植物中单萜、倍半萜、二萜以及三萜化合物的种类以及对昆虫的生物活性等方面进行了论述。     

HPLC-ESI-IT-MS/MS Analysis and Biological Activity of Triterpene Glycosides from the Colombian Marine Sponge Ectyoplasia ferox

The marine sponge Ectyoplasia ferox produces antipredatory and allelopathic triterpenoid glycosides as part of its chemical defense repertoire against predators, competitors, and fouling organisms. These molecules are responsible for the pharmacological potential found in the glycosides present in this species. In order to observe the glycochemical diversity present in E. ferox, a liquid chromatography coupled to a tandem mass spectrometry approach to analyse a complex polar fraction of this marine sponge was performed. This gave valuable information for about twenty-five compounds three of which have been previously reported and another three which were found to be composed of known aglycones. Furthermore, a group of four urabosides, sharing two uncommon substitutions with carboxyl groups at C-4 on the terpenoid core, were identified by a characteristic fragmentation pattern. The oxidized aglycones present in this group of saponins can promote instability, making the purification process difficult. Cytotoxicity, cell cycle modulation, a cell cloning efficiency assay, as well as its hemolytic activity were evaluated. The cytotoxic activity was about IC₅₀ 40 µg/mL on Jurkat and CHO-k₁ cell lines without exhibiting hemolysis. Discussion on this bioactivity suggests the scanning of other biological models would be worthwhile.     

Canopy position affects rind biochemical profile of ‘Nules Clementine’ mandarin fruit during postharvest storage

This study was conducted to investigate the effects of preharvest canopy position and bagging treatments on rind physiological and biochemical properties of ‘Nules Clementine’ mandarin (Citrus reticulata Blanco) fruit. Before storage, the respiration rate of unbagged outside fruit was significantly higher (21.6 mL CO₂ kg⁻¹ h⁻¹) than of bagged inside fruit (16.3 mL CO₂ kg⁻¹ h⁻¹). Unbagged fruit outside the canopy had 1.4-fold higher carbohydrates, and 1.1-fold higher dry matter (DM) content than bagged inside fruit. Bagged fruit inside the canopy had higher (24%) weight loss than outside sun-exposed fruit (14%). This corresponded with a higher rind breakdown (RBD) index for bagged inside fruit, compared to sun-exposed fruit which did not develop the disorder. During postharvest storage, rind fructose levels of bagged fruit inside the canopy increased from 62.4 mg/g DM at harvest to 81.3 mg/g DM after 8 weeks, while those of unbagged outside fruit increased from 97.9 to 108.4 mg/g DM. Concomitant with the increase in fructose, sucrose in rind tissue of bagged inside fruit decreased from 42.6 to 27.7 mg/g DM and from 49.3 to 33.4 mg/g DM for unbagged outside fruit. Rind glucose of unbagged inside fruit decreased from 90.6 to 76.2 mg/g DM. Ascorbic acid concentrations remained almost constant during storage, with levels between 3.3 and 6.7 mg/g DM for inside bagged and unbagged outside fruit, respectively. Hesperidin was the major flavanone detected, with concentrations between 35 and 45 mg/g DM followed by narirutin (1.1–2.8 mg/g DM). At harvest, rind of fruit harvested from outside the canopy had lower hesperidin concentration (38.1 mg/g DM) compared to shaded fruit (44.2 mg/g DM). Overall, the results suggest that variations in microclimatic conditions inside the tree canopy during the growing season affect the biochemical profile of the fruit rind, which in turn influences fruit response to postharvest stresses associated with senescence and susceptibility to RBD.     

连翘叶活性成分不同提取方法的研究

[目的]探讨连翘叶活性成分的最佳提取方法。[方法]分别以黄酮类、木脂素类和三萜酸类提取率和含量为指标,考察有机溶剂回流提取法、索氏提取法、微波提取和超声提取方法进行对比研究。[结果]超声提取法对黄酮类和木脂素类的提取效果最佳;有机溶剂回流提取法对三萜酸的提取效果最佳。[结论]试验探讨了连翘叶活性成分的最佳提取方法,为工业生产提取提供了理论依据。     

三株坦桑尼亚野生灵芝菌株人工栽培子实体活性成分含量分析

以国内灵芝(Ganoderma)栽培菌株粤GL-YW( G.lucidum)和粤GL-YWZ(G.sinense)为对照,对3株采自坦桑尼亚的野生灵芝(Ganoderma)菌株的人工栽培子实体进行多糖和三萜含量测定.结果表明,3个野生菌株子实体中多糖和三萜含量均显著高于对照菌株,值得进一步开发和推广.     

不同粉碎程度对灵芝多糖与三萜提取得率的影响

以3个品种的灵芝(Ganoderma lucidum)子实体为材料,比较了不同粉碎程度对灵芝多糖与三萜提取效果的影响,结果表明,超细粉碎工艺能够有效地破碎灵芝子实体中的菌丝细胞,显著提高灵芝多糖的提取率,但对三萜的提取结果没有影响.     

Qualitative and Quantitative Saponin Contents in Five Sea Cucumbers from the Indian Ocean

To avoid predation, holothuroids produce feeding-deterrent molecules in their body wall and viscera, the so-called saponins. Five tropical sea cucumber species of the family Holothuriidae were investigated in order to study their saponin content in two different organs, the body wall and the Cuvierian tubules. Mass spectrometry techniques (MALDI- and ESI-MS) were used to detect and analyze saponins. The smallest number of saponins was observed in Holothuria atra, which contained a total of four congeners, followed by Holothuria leucospilota, Pearsonothuria graeffei and Actinopyga echinites with six, eight and ten congeners, respectively. Bohadschia subrubra revealed the highest saponin diversity (19 congeners). Saponin mixtures also varied between the two body compartments within a given animal. A semi-quantitative approach completed these results and showed that a high diversity of saponins is not particularly correlated to a high saponin concentration. Although the complexity of the saponin mixtures described makes the elucidation of their respective biological roles difficult, the comparisons between species and between body compartments give some clues about how these molecules may act as predator repellents.