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1.
The n‐alkane composition in the leaf cuticular waxes of natural populations of Bosnian pine (Pinus heldreichii), Austrian pine (P. nigra), and Macedonian pine (P. peuce) was compared for the first time. The range of n‐alkanes was wider in P. nigra (C16 – C33) than in P. heldreichii and P. peuce (C18 – C33). Species also diverged in abundance and range of dominant n‐alkanes (P. heldreichii: C23, C27, and C25; P. nigra: C25, C27, C29, and C23; P. peuce: C29, C25, C27, and C23). Multivariate statistical analyses (PCA, DA, and CA) generally pointed out separation of populations of P. nigra from populations of P. heldreichii and P. peuce (which were, to a greater or lesser extent, separated too). However, position of these species on the basis of n‐alkane composition was in accordance neither with infrageneric classification nor with recent molecular and terpene investigations.  相似文献   

2.
Centaurea ragusina L., an endemic Croatian plant species, revealed a good cytotoxic activity of aqueous extracts (AE) on human bladder (T24) and human glioblastoma (A1235) cancer cell lines. The chemical constituents were tentatively identified using high performance liquid chromatography HPLC‐DAD/ESI‐TOF‐MS in negative ionization mode. The main compounds of herba extract were sesquiterpene lactones: solstitialin A 3,13‐diacetate and epoxyrepdiolide; organic acid: quinic acid. The main compounds of flower extract were organic acids: quinic acid, citric acid, and malic acid; sesquiterpene lactone: cynaropicrin; phenolic compounds: chlorogenic acid and phenylpropanoid: syringin. The AE of Cragusina were investigated for correlation of their effects on human bladder (T24) and human glioblastoma (A1235) cancer cell lines using the MTT assay. Although both extracts showed significant dose‐ and time‐dependent cytotoxic activity against both cancer cell lines, the flower extract exhibited slightly higher activity. In order to determine type of cell death induced by treatment, cell lines were exposed subsequently to a treatment with both flower and herba AE. The majority of the cells died by induced apoptosis treatment. Flower AE (26.25%), compared to a leaf AE (22.15%) showed slightly higher percentage of an apoptosis in T24 cells, when compared to a non‐treated cells (0.04%).  相似文献   

3.
Seed dispersal selection pressures may cause morphological differences in cone structure and seed traits of large‐seeded pine trees. We investigated the cone, seed, and scale traits of four species of animal‐dispersed pine trees to explore the adaptations of morphological structures to different dispersers. The four focal pines analyzed in this study were Chinese white pine (Pinus armandi), Korean pine (P. koraiensis), Siberian dwarf pine (P. pumila), and Dabieshan white pine (P. dabeshanensis). There are significant differences in the traits of the cones and seeds of these four animal‐dispersed pines. The scales of Korean pine and Siberian dwarf pine are somewhat opened after cone maturity, the seeds are closely combined with scales, and the seed coat and scales are thick. The cones of Chinese white pine and Dabieshan white pine are open after ripening, the seeds fall easily from the cones, and the seed coat and seed scales are relatively thin. The results showed that the cone structure of Chinese white pine is similar to that of Dabieshan white pine, whereas Korean pine and Siberian dwarf pine are significantly different from the other two pines and vary significantly from each other. This suggests that species with similar seed dispersal strategies exhibit similar morphological adaptions. Accordingly, we predicted three possible seed dispersal paradigms for animal‐dispersed pines: the first, as represented by Chinese white pine and Dabieshan white pine, relies upon small forest rodents for seed dispersal; the second, represented by Korean pine, relies primarily on birds and squirrels to disperse the seeds; and the third, represented by Siberian dwarf pine, relies primarily on birds for seed dispersal. Our study highlights the significance of animal seed dispersal in shaping cone morphology, and our predictions provide a theoretical framework for research investigating the coevolution of large‐seeded pines and their seed dispersers.  相似文献   

4.
Breast cancer constitutes the second most prevalent cancer in Egypt, the problem needs more trends in treatment and treatment development either by regimen modification or introducing new drugs, and the main objective of this study is to screen the effects of the aqueous ethanol herbal extract of Luffa cylindrica leaves on different types of breast cancer cell lines representing different molecular subtypes of the disease. The major active constituents of the extract were tentatively identified by LC/MS which revealed the presence of phenolic compound derivatives and saponin that may be responsible in part for the activity of the extract. The emphasis was laid on the main apoptotic pathways as well as the extract effect on the normal cell line. Results of phytochemical investigation, cell cycle analysis, and molecular analysis of apoptotic and proliferative markers have shown effective anticancer activity against MCF‐7, BT‐474, and MDA‐MB‐231 cell lines which represent three subtypes of breast cancer, luminal A, luminal B, and triple negative, respectively. On the other hand, the effects on normal lung fibroblast cell line are less prominent at the dose used for treating breast cancer cell lines.  相似文献   

5.
Seventeen steviol derivatives, i.e., 2 – 18 , and 19 isosteviol derivatives, i.e., 19 – 37 , were prepared from a diterpenoid glycoside, stevioside ( 1 ). Upon evaluation of the cytotoxic activities of these compounds against leukemia (HL60), lung (A549), stomach (AZ521), and breast (SK‐BR‐3) cancer cell lines, nine steviol derivatives, i.e., 5 – 9 and 11 – 14 , and five isosteviol derivatives, i.e., 28 – 32 , exhibited activities with single‐digit micromolar IC50 values against one or more cell lines. All of these active compounds possess C(19)‐O‐acyl group, and among which, ent‐kaur‐16‐ene‐13,19‐diol 19‐O‐4′,4′,4′‐trifluorocrotonate ( 14 ) exhibited potent cytotoxicities against four cell lines with IC50 values in the range of 1.2–4.1 μM . Compound 14 induced typical apoptotic cell death in HL60 cells upon evaluation of the apoptosis‐inducing activity by flow‐cytometric analysis. These results suggested that acylation of the 19‐OH group of kaurane‐ and beyerane‐type diterpenoids might be useful for enhancement of their cytotoxicities with apoptosis‐inducing activity.  相似文献   

6.
Background and Aim: Our previous study of Helicobacter pylori‐induced apoptosis showed the involvement of Bcl‐2 family proteins and cytochrome c release from mitochondria. Here, we examine the release of other factors from mitochondria, such as apoptosis‐inducing factor (AIF), and upstream events involving caspase‐8 and Bid. Methods: Human gastric adenocarcinoma (AGS) cells were incubated with a cagA‐positive H. pylori strain for 0, 3, 6, and 24 hours and either total protein or cytoplasmic, nuclear, and mitochondrial membrane fractions were collected. Results: Proteins were immunoblotted for AIF, Bid, polyadenosine ribose polymerase (PARP), caspase‐8, and β‐catenin. H. pylori activated caspase‐8, caused PARP cleavage, and attenuated mitochondrial membrane potential. A time‐dependent decrease in β‐catenin protein expression was detected in cytoplasmic and nuclear extracts, coupled with a decrease in β‐actin. An increase in the cytoplasmic pool of AIF was seen as early as 3 hours after H. pylori exposure, and a concomitant increase was seen in nuclear AIF levels up to 6 hours. A band corresponding to full‐length Bid was seen in both the cytoplasmic and the nuclear fractions of controls, but not after H. pylori exposure. Active AIF staining was markedly increased in gastric mucosa from infected persons, compared to uninfected controls. Conclusion: H. pylori might trigger apoptosis in AGS cells via interaction with death receptors in the plasma membrane, leading to the cleavage of procaspase‐8, release of cytochrome c and AIF from mitochondria, and activation of subsequent downstream apoptotic events, as reported previously for chlorophyllin. This is consistent with AIF activation that was found in the gastric mucosa of humans infected with H. pylori. Hence, the balance between apoptosis and proliferation in these cells may be altered in response to injury caused by H. pylori infection, leading to an increased risk of cancer.  相似文献   

7.
8.
Twelve Salpichroa taxa have been phytochemically analyzed. From the aerial parts of Sscandens, four known salpichrolides A, C, I, S, and an unreported withanolide named salpichrolide V ( 1 ), were isolated. In Sdependens, Sgayi, Sglandulosa subsp. glandulosa, Sglandulosa subps. weddellii, Sleucantha, Smicrantha, Smicroloba, Sproboscidea, Sramosissima, Stristis var. tristis, and Sweberbauerii, no withanolides were found. The chemical content of ca. 85% of the Salpichroa taxa is in agreement with molecular studies, which suggest that Salpichroa and Jaborosa, a genus considered morphologically close to Salpichroa, are distant in the systematic of the Solanoideae subfamily. Moreover, the in vitro cytotoxic activity of a set of natural salpichrolides and derivatives was examined against two prostate carcinoma cell lines (PC3 and LNCaP) and two human breast cancer cell lines (MCF‐7 and T47D). Several compounds showed moderate activity (IC50 = 64.91 – 29.97 μm ).  相似文献   

9.
Comparative analysis of terpene diversity and differentiation of relict pines Pinus heldreichii, Pnigra, and P. peuce from the central Balkans was performed at the population level. Multivariate statistical analyses showed that the composition of needle terpenes reflects clear divergence among the pine species from different subgenera: P. peuce (subgenus Strobus) vs. P. nigra and P. heldreichii (subgenus Pinus). In addition, despite the described morphological similarities and the fact that P. nigra and P. heldreichii may spontaneously hybridize, our results indicated differentiation of their populations naturally growing in the same area. In accordance with recently proposed concept of ‘flavonic evolution’ in the genus Pinus, we assumed that the terpene profile of soft pine P. peuce, defined by high amounts of six monoterpenes, is more basal than those of hard pines P. nigra and P. heldreichii, which were characterized by high content levels of mainly sesquiterpenes. In order to establish precise positions of P. heldreichii, P. nigra and P. peuce within the taxonomic and phylogenetic tree, as well as develop suitable conservation strategies and future breeding efforts, it is necessary to perform additional morphological, biochemical, and genetic studies.  相似文献   

10.
The arial parts of Scutellaria barbata D. Don (Lamiaceae) efficiently inhibited NO production in BV2 microglial cells, and the active constituents were further isolated based on activity‐guided isolation using silica‐gel column chromatography, RP‐C18 MPLC and prep‐HPLC. As the results, 2 flavonoids including 6‐methoxynaringenin ( 1 ) and 6‐O‐methylscutellarein ( 5 ), and 6 neo‐clerodane diterpenes such as scutebarbatine W ( 2 ), scutebatas B ( 3 ), scutebarbatine B ( 4 ), scutebarbatine A ( 6 ), 6‐O‐nicotinolylscutebarbatine G ( 7 ), and scutebarbatine X ( 8 ) were isolated. The structures of these compounds were elucidated based on NMR and MS data, and the comparison of literature values. All the compounds except compound 7 inhibited NO production efficiently with IC50 values of lower than 50 μm . Particularly, compounds 1 and 8 were the most efficient with IC50 values of 25.8 and 27.4 μm , respectively. This is the first report suggesting the potential of S. barbata on the reduction of neuroinflammation.  相似文献   

11.
The composition of oil samples isolated from needles of Pinus halepensis growing in three locations in Corsica (Saleccia, Capo di Feno, and Tre Padule) has been investigated by combination of chromatographic (GC with retention indices) and spectroscopic (MS and 13C‐NMR) techniques. In total, 35 compounds that accounted for 77 – 100% of the whole composition have been identified. α‐Pinene, myrcene, and (E)‐β‐caryophyllene were the major component followed by α‐humulene and 2‐phenylethyl isovalerate. Various diterpenes have been identified as minor components. 47 Oil samples isolated from pine needles have been analyzed and were differentiated in two groups. Oil samples of the first group (15 samples) contained myrcene (M = 28.1 g/100 g; SD = 10.6) and (E)‐β‐caryophyllene (M = 19.0 g/100 g; SD = 2.2) as major components and diterpenes were absent. All these oil samples were isolated from pine needles harvested in Saleccia. Oil samples of the second group (32 samples) contained mostly (E)‐β‐caryophyllene (M = 28.7 g/100 g; SD = 7.9), α‐pinene (M = 12.3 g/100 g; SD = 3.6), and myrcene (M = 11.7 g/100 g; SD = 7.3). All these oil samples were isolated from pine needles harvested in Capo di Feno and Tre Padule.  相似文献   

12.
目的:不可逆电穿孔是治疗肿瘤的新兴技术,本文探讨高压电场引起的不可逆电穿孔诱发A549 肺癌细胞凋亡的特点。方 法:选择处于生长周期的A549细胞,共分为A-G7 个组进行研究,其中A组为不施加电场的空白对照组,B-G 组为实验组,B 组 施加500 V/cm 强度高压电场,G 组施加1750 V/cm的高压电场,BG 组之间各组的高压电场强度间隔为250 V/cm。采取细胞抑制 实验、不可逆电穿孔示踪实验、细胞凋亡实验,检验A549 细胞细胞凋亡与电场强度的关系。结果:①各实验组与对照组、各实验组 之间的细胞抑制率,均存在显著性差异(P<0.05);② 电场强度≥ 1000V/cm时,细胞不可逆电穿孔率明显增加,有统计学意义(P<0.05);电 场强度≥ 1500 V/cm 时,细胞不可逆电穿孔率增加不明显,无统计学意义(P>0.05);③ 电场强度≥ 1250 V/cm时,细胞早期凋亡率 明显增加,有统计学意义(P<0.05)。结论:高压电场不可逆电穿孔诱发A549 肺癌细胞发生早期凋亡的强度为1250 V/cm,发生晚期 凋亡的强度为1500 V/cm,且凋亡率随着电场强度的增加持续升高。这对于高压电场不可逆电穿孔效应引起的肿瘤细胞凋亡机制 的研究具有重要意义。  相似文献   

13.
目的:不可逆电穿孔是治疗肿瘤的新兴技术,本文探讨高压电场引起的不可逆电穿孔诱发A549肺癌细胞凋亡的特点。方法:选择处于生长周期的A549细胞,共分为A—G7个组进行研究,其中A组为不施加电场的空白对照组,B-G组为实验组,B组施加500V/cm强度高压电场,G组施加1750V/cm的高压电场,BG组之间各组的高压电场强度间隔为250V/cm。采取细胞抑制实验、不可逆电穿孔示踪实验、细胞凋亡实验,检验A549细胞细胞凋亡与电场强度的关系。结果:①各实验组与对照组、各实验组之间的细胞抑制率,均存在显著性差异(P〈0.05);②电场强度≥1000V/cm时,细胞不可逆电穿孔率明显增加,有统计学意义(P〈0.05);电场强度≥1500V/cm时,细胞不可逆电穿孔率增加不明显,无统计学意义(P〉0.05);③电场强度≥1250V/cm时,细胞早期凋亡率明显增加,有统计学意义(P〈0.05)。结论:高压电场不可逆电穿孔诱发A549肺癌细胞发生早期凋亡的强度为1250V/cm,发生晚期凋亡的强度为1500V/cm,且凋亡率随着电场强度的增加持续升高。这对于高压电场不可逆电穿孔效应引起的肿瘤细胞凋亡机制的研究具有重要意义。  相似文献   

14.
Phytochemical investigation from the tube roots of Butea superba, led to the isolation and identification of a new 2‐aryl‐3‐benzofuranone named superbanone ( 1 ), one benzoin, 2‐hydroxy‐1‐(2‐hydroxy‐4‐methoxyphenyl)‐2‐(4‐methoxyphenyl)ethanone ( 2 ), eight pterocarpans ( 3  –  10 ), and eleven isoflavonoids ( 11  –  21 ). Compound 2 was identified for the first time as a natural product. The structure of the isolated compounds was elucidated using spectroscopic methods, mainly 1D‐ and 2D‐NMR. The isolated compounds and their derivatives were evaluated for α‐glucosidase inhibitory and antimalarial activities. Compounds 3 , 7 , 8 , and 11 showed promising α‐glucosidase inhibitory activity (IC50 = 13.71 ± 0.54, 23.54 ± 0.75, 28.83 ± 1.02, and 12.35 ± 0.36 μm , respectively). Compounds 3 and 11 were twofold less active than the standard drug acarbose (IC50 = 6.54 ± 0.04 μm ). None of the tested compounds was found to be active against Plasmodium falciparum strain 94. On the basis of biological activity results, structure–activity relationships are discussed.  相似文献   

15.
Four limonoids, 1  –  4 , five alkaloids, 5  –  9 , and four phenolic compounds, 10  –  13 , were isolated from a MeOH extract of the bark of Phellodendron amurense (Rutaceae). Among these, compound 13 was new, and its structure was established as rel‐(1R,2R,3R)‐5‐hydroxy‐3‐(4‐hydroxy‐3‐methoxyphenyl)‐6‐methoxy‐1‐(methoxycarbonylmethyl)indane‐2‐carboxylic acid methyl ester (γ‐di(methyl ferulate)) based on the spectrometric analysis. Upon evaluation of compounds 1  –  13 against the melanogenesis in the B16 melanoma cells induced with α‐melanocyte‐stimulating hormone (α‐MSH), four compounds, limonin ( 1 ), noroxyhydrastinine ( 6 ), haplopine ( 7 ), and 4‐methoxy‐1‐methylquinolin‐2(1H)‐one ( 8 ), exhibited potent melanogenesis‐inhibitory activities with almost no toxicity to the cells. Western blot analysis revealed that compound 6 inhibited melanogenesis, at least in part, by inhibiting the expression of protein levels of tyrosinase, TRP‐1, and TRP‐2 in α‐MSH‐stimulated B16 melanoma cells. In addition, when compounds 1  –  13 were evaluated for their cytotoxic activities against leukemia (HL60), lung (A549), duodenum (AZ521), and breast (SK‐BR‐3) cancer cell lines, five compounds, berberine ( 5 ), 8 , canthin‐6‐one ( 9 ), α‐di‐(methyl ferulate) ( 12 ), and 13 , exhibited cytotoxicities against one or more cancer cell lines with IC50 values in the range of 2.6 – 90.0 μm . In particular, compound 5 exhibited strong cytotoxicity against AZ521 (IC50 2.6 μm ) which was superior to that of the reference cisplatin (IC50 9.5 μm ).  相似文献   

16.
黄酮和黄酮醇通过诱导PIG3表达引发人食管癌细胞凋亡   总被引:3,自引:0,他引:3  
采用两株人食管癌细胞(鳞癌KYSE-510和腺癌OE33)为肿瘤模型,在体外探讨黄酮、黄酮醇化合物诱导细胞凋亡的分子机制.DNA片段化、吖啶橙染色以及流式细胞术的分析结果表明,3种黄酮(木犀草素、白杨素、芹菜素)和3种黄酮醇(槲皮素、山奈酚、杨梅素)均能诱导两株食管癌细胞发生凋亡.荧光定量RT-PCR和Western-blot分析结果表明,黄酮和黄酮醇是通过诱导PIG3 mRNA和蛋白质的表达、经线粒体途径以非p53依赖的方式,引发两株食管癌细胞凋亡.同时,这一过程可能受到p63和p73的调节.  相似文献   

17.
The genus Acacia is quite large and can be found in the warm subarid and arid parts, but little is known about its chemistry, especially the volatile parts. The volatile oils from fresh flowers of Amollissima and Acyclops (growing in Tunisia) obtained by hydrodistillation were analyzed by GC then GC/MS. Eighteen (94.7% of the total oil composition) and 23 (97.4%) compounds were identified in these oils, respectively. (E,E)‐α‐Farnesene (51.5%) and (E)‐cinnamyl alcohol (10.7%) constituted the major compounds of the flower oil of Amollissima, while nonadecane (29.6%) and caryophyllene oxide (15.9%) were the main constituents of the essential oil of Acyclops. Antioxidant activity of the isolated oils was studied by varied assays, i.e., 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2‐azinobis 3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS); the isolated oils showed lowest IC50 (4 – 39 μg/ml) indicating their high antioxidant activity. The α‐glucosidase inhibitor activity was also evaluated and Acacia oils were found to be able to strongly inhibit this enzyme with IC50 values (81 – 89 μg/ml) very close to that of acarbose which was used as positive control. Furthermore, they were tested against five Gram‐positive and Gram‐negative bacteria and one Candida species. Essential oil of Amollissima was found to be more active than that of Acyclops, especially against Pseudomonas aeruginosa (MIC = 0.31 mg/ml and MBC = 0.62 mg/ml).  相似文献   

18.
19.
This study was performed to determine the chemical composition, antioxidant and cytotoxic effects of essential oils extracted from the aerial parts of fresh (F‐PSEO) and air‐dried (D‐PSEO) Pallenis spinosa. The composition of the oils was analyzed by gas chromatography (GC) and GC/mass spectrometry, the antioxidant activity by free radical scavenging and metal chelating assays, and their cytotoxicity by a flow cytometry analysis. The primary components in both oils were sesquiterpene hydrocarbons and oxygentated sesquiterpenes. F‐PSEO contained 36 different compounds; α‐cadinol (16.48%), germacra‐1(10),5‐diene‐3,4‐diol (14.45%), γ‐cadinene (12.03%), and α‐muurolol (9.89%) were the principal components. D‐PSEO contained 53 molecules; α‐cadinol (19.26%), δ‐cadinene (13.93%), α‐muurolol (12.88%), and germacra‐1(10),5‐diene‐3,4‐diol (8.41%) constituted the highest percentages. Although both oils exhibited a weak radical scavenging and chelating activity, compared to α‐tocopherol and ascorbic acid, D‐PSEO showed a 2‐fold greater antioxidant activity than F‐PSEO. Furthermore, low doses of F‐PSEO were able to inhibit the growth of leukemic (HL‐60, K562, and Jurkat) and solid tumor cells (MCF‐7, HepG2, HT‐1080, and Caco‐2) with an IC50 range of 0.25 – 0.66 μg/ml and 0.50 – 2.35 μg/ml, respectively. F‐PSEO showed a ca. 2 – 3‐fold stronger cytotoxicity against the tested cells than D‐PSEO. The potent growth inhibitory effect of the plant essential oil encourages further studies to characterize the molecular mechanisms of its cytotoxicity.  相似文献   

20.
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