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1.
Ganoderic acids (GAs) Mk, T, S and R exhibit promising anti-tumor effect, but they are difficult to purify from Ganoderma lucidum mycelia due to the presence of numerous analogs. In this work, a novel and efficient extraction/hydrolysis method was developed for the recovery of these four GAs from the mycelia of G. lucidum. By using a 50% aqueous ethanol solution containing 50 mmol/l HCl as extractant, extraction of GAs from mycelia and conversion of analogs impurities into the products of interest could be achieved in one step. This one-pot extraction/hydrolysis process increased the yield of GA-Mk, -T, -S and -R to 242%, 389%, 189% and 420%, respectively, compared to a raw sample without hydrolysis. Simultaneous purification of these four GAs was readily achieved in a single RP-HPLC run due to the conversion of analog impurities into corresponding desired GAs, and the purity and recovery of these four GAs were over 97% and 90%, respectively. The results demonstrated that the simultaneous extraction and hydrolysis process is simple and efficient and thus can act as a useful approach for enhanced recovery of those four GAs from G. lucidum mycelia.  相似文献   

2.
Bioactive gibberellins (GAs) play a key regulatory role in plant growth and development. In the biosynthesis of GAs, GA3-oxidase catalyzes the final step to produce bioactive GAs. Thus, the evaluation of GA3-oxidase activity is critical for elucidating the regulation mechanism of plant growth controlled by GAs. However, assessing catalytic activity of endogenous GA3-oxidase remains challenging. In the current study, we developed a capillary liquid chromatography – mass spectrometry (cLC-MS) method for the sensitive assay of in-vitro recombinant or endogenous GA3-oxidase by analyzing the catalytic substrates and products of GA3-oxidase (GA1, GA4, GA9, GA20). An anion exchange/hydrophobic poly([2-(methacryloyloxy)ethyl]trimethylammonium-co-divinylbenzene-co-ethylene glycol dimethacrylate)(META-co-DVB-co-EDMA) monolithic column was successfully prepared for the separation of all target GAs. The limits of detection (LODs, Signal/Noise = 3) of GAs were in the range of 0.62–0.90 fmol. We determined the kinetic parameters (K m) of recombinant GA3-oxidase in Escherichia coli (E. coli) cell lysates, which is consistent with previous reports. Furthermore, by using isotope labeled substrates, we successfully evaluated the activity of endogenous GA3-oxidase that converts GA9 to GA4 in four types of plant samples, which is, to the best of our knowledge, the first report for the quantification of the activity of endogenous GA3-oxidase in plant. Taken together, the method developed here provides a good solution for the evaluation of endogenous GA3-oxidase activity in plant, which may promote the in-depth study of the growth regulation mechanism governed by GAs in plant physiology.  相似文献   

3.
A convenient method of preparing permethyl derivatives of GAs and GA-glucosides is described using NaH and MeI in DMF. The permethyl derivatives of the glucosides give sharp GC peaks and their MS provide information for the identification of the GA and carbohydrate moieties. The detection and characterization of endogenous GAs and GA-glycosides in pods of Phaseolus coccineus by GC-MS of permethylated extracts are described. Permethylation of carbohydrates, IAA, ABA and cytokinins by the same method is described.  相似文献   

4.
We conducted gross and microscopic characterizations of lesions in Cnidaria from Palmyra Atoll, Central Pacific. We found growth anomalies (GA) to be the most commonly encountered lesion. Cases of discoloration and tissue loss were rare. GAs had a focal or multi-focal distribution and were predominantly nodular, exophytic, and umbonate. In scleractinians, the majority of GAs manifested as hyperplasia of the basal body wall (52% of cases), with an associated absence or reduction of polyp structure (mesenteries and filaments, actinopharynx and tentacles), and depletion of zooxanthellae in the gastrodermis of the upper body wall. In the soft corals Sinularia sp. and Lobophytum sp., GAs exclusively manifested as prominent hyperplasia of the coenenchyme with an increased density of solenia. In contrast to scleractinians, soft coral GAs displayed an inflammatory and necrotizing component with marked edema of the mesoglea, accompanied by infiltrates of variably-sized granular amoebocytes. Fungi, algae, sponges, and Crustacea were present in some scleractinian GAs, but absent in soft coral GAs. Fragmentation of tissues was a common finding in Acropora acuminata and Montipora cf. dilatata colonies with tissue loss, although no obvious causative agents were seen. Discoloration in the zoanthid, Palythoa tuberculosa, was found to be the result of necrosis, while in Lobophytum sp. discoloration was the result of zooxanthellar depletion (bleaching). Soft corals with discoloration or tissue loss showed a marked inflammatory response, however no obvious causative organisms were seen. Lesions that appeared similar at the gross level were revealed to be distinct by microscopy, emphasizing the importance of histopathology.  相似文献   

5.
2种石蒜生长发育期鳞茎内源激素的动态变化   总被引:4,自引:0,他引:4  
应用酶联免疫吸附测定法(ELISA)研究了石蒜与中国石蒜不同生长发育期鳞茎内源激素质量摩尔浓度的动态变化,分析了内源激素与2种石蒜生长发育的关系。结果表明,花芽分化前期2种石蒜鳞茎IAA浓度较低,而iPAs、ABA与GAs浓度较高;临近抽葶IAA浓度均有所增加,而iPAs与Zrs、ABA与GAs浓度均降到极值。花期ABA、GAs与ZRs浓度均有所回升,说明高浓度的ABA与GAs对2种石蒜的开花可能起正向调控的作用,但对叶生长的协同规律不明显。内源激素比例分析表明,ZRs/IAA、GAs/IAA、ABA/GAs三者比例高有利于2种石蒜的花原基分化,三者比例低则有助于2种石蒜的叶生长。  相似文献   

6.
The endogenous gibberellins (GAs) of pollen of Pinus attenuata, P. coulteri, and P. ponderosa were bioassayed at hour 0, 3, 15, 24, 48 and 72 of germination. Dormant pollen showed relatively high GA activity throughout the elution spectrum (i.e. ranging from relatively nonpolar to highly polar). The maximum GA activity was obtained at hour 15 in more polar regions and especially in the zone corresponding to GA3 (for P. attenuata estimated as 250 micrograms of GA3/kilogram pollen). It is probable that the “nonpolar” GAs present in high quantities in dormant pollen and in early stages of germination were converted to “more polar” GAs as germination progressed. The amount of all GAs decreased after hour 15 of germination and by hour 72 no GAs could be detected. Among the species tested P. attenuata showed the highest over-all GA activity.  相似文献   

7.
Polysaccharides and ganoderic acids (GAs) are the major bioactive constituents of Ganoderma species. However, the commercialization of their production was limited by low yield in the submerged culture of Ganoderma despite improvement made in recent years. In this work, twelve Ganoderma strains were screened to efficiently produce polysaccharides and GAs, and Ganoderma lucidum 5.26 (GL 5.26) that had been never reported in fermentation process was found to be most efficient among the tested stains. Then, the fermentation medium was optimized for GL 5.26 by statistical method. Firstly, glucose and yeast extract were found to be the optimum carbon source and nitrogen source according to the single-factor tests. Ferric sulfate was found to have significant effect on GL 5.26 biomass production according to the results of Plackett–Burman design. The concentrations of glucose, yeast extract and ferric sulfate were further optimized by response surface methodology. The optimum medium composition was 55 g/L of glucose, 14 g/L of yeast extract, 0.3 g/L of ferric acid, with other medium components unchanged. The optimized medium was testified in the 10-L bioreactor, and the production of biomass, IPS, total GAs and GA-T enhanced by 85, 27, 49 and 93 %, respectively, compared to the initial medium. The fermentation process was scaled up to 300-L bioreactor; it showed good IPS (3.6 g/L) and GAs (670 mg/L) production. The biomass was 23.9 g/L in 300-L bioreactor, which was the highest biomass production in pilot scale. According to this study, the strain GL 5.26 showed good fermentation property by optimizing the medium. It might be a candidate industrial strain by further process optimization and scale-up study.  相似文献   

8.
9.
Aharoni N 《Plant physiology》1978,62(2):224-228
Levels of gibberillins (GAs) and of abscisic acid (ABA) in attached leaves of romaine lettuce (Lactuca sativa L.) declined as the leaf became older. The time course of changes in hormone levels, determined in detached lettuce leaves kept in darkness, revealed that a sharp decline in GAs accompanied by a moderate rise in ABA occurred before the onset of chlorophyll degradation. As senescence advanced, no GAs could be detected and a considerable rise of ABA was observed. A similar sequence of hormonal modifications, but more pronounced, was observed in the course of accelerated senescence induced by either Ethephon or water stress. When kinetin or GA3 was applied to detached leaves, the loss of chlorophyll and the rise in ABA were reduced. Bound GAs were detected in senescent leaves. They were not found in the kinetin-treated leaves, which contained a relatively high level of free GAs. The results suggest that senescence in detached romaine lettuce leaves is connected with a depletion of free GAs and cytokinins, which is thereafter followed by a great surge in ABA.  相似文献   

10.
Ganoderma lucidum (G. lucidum) main attractive pharmacological characteristics are antitumor and immunomodulatory activities which are chiefly associated with its two principal bioactive compounds, those are polysaccharides and triterpenoids. Ganoderic acids (GAs) are one of the most discovered triterpenoids of G. lucidum among various triterpenoids. The prominent medicinal mushroom G. lucidum possesses GAs as essential bioactive constituents that are highly oxygenated lanostane-type triterpenoids. GAs exhibit diverse potential action against numerous diseases such as anticancer, antioxidant, anti-inflammatory, anti-HIV, cardioprotective, antiallergic, antihepatotoxic, neuroprotective and antinociceptive properties. GAs act through different mechanisms that include cytotoxic, apoptosis, inducing cell cycle arrest, inhibition of topoisomerases, antiproliferation, anti-invasion, inhibition of NF-kB AP1/uPA, farnesyl protein transferase and JAK-STAT3 pathway. The miraculous effects of GAs fascinate the researchers for their production. Various environmental factors such as biochemical signals, nutritional and physical that influence the biosynthesis of GA. However, the scarcities of pure compounds or accurately characterized extracts are the main problem of clinical studies. Substantial steps are required for characterized extracts of active compounds. This review contributes a thorough insight into the mode of actions of GAs and their possible reinforcements to overcome various diseases.  相似文献   

11.
12.

Background

Cholangiocarcinoma (CCA) is clinically heterogeneous; intra and extrahepatic CCA have diverse clinical presentations. Next generation sequencing (NGS) technology may identify the genetic differences between these entities and identify molecular subgroups for targeted therapeutics.

Methods

We describe successful NGS-based testing of 75 CCA patients along with the prognostic and therapeutic implications of findings. Mutation profiling was performed using either a) NGS panel of hotspot regions in 46 cancer-related genes using a 318-chip on Ion PGM Sequencer or b) Illumina HiSeq 2000 sequencing platform for 3,769 exons of 236 cancer-related genes plus 47 introns from 19 genes to an average depth of 1000X. Clinical data was abstracted and correlated with clinical outcome. Patients with targetable mutations were referred to appropriate clinical trials.

Results

There were significant differences between intrahepatic (n = 55) and extrahepatic CCA (n = 20) in regard to the nature and frequency of the genetic aberrations (GAs). IDH1 and DNA repair gene alterations occurred more frequently in intrahepatic CCA, while ERBB2 GAs occurred in the extrahepatic group. Commonly occurring GAs in intrahepatic CCA were TP53 (35%), KRAS (24%), ARID1A (20%), IDH1 (18%), MCL1 (16%) and PBRM1 (11%). Most frequent GAs in extrahepatic CCA (n = 20) were TP53 (45%), KRAS (40%), ERBB2 (25%), SMAD4 (25%), FBXW7 (15%) and CDKN2A (15%). In intrahepatic CCA, KRAS, TP53 or MAPK/mTOR GAs were significantly associated with a worse prognosis while FGFR GAs correlated with a relatively indolent disease course. IDH1 GAs did not have any prognostic significance. GAs in the chromatin modulating genes, BAP1 and PBRM1 were associated with bone metastases and worse survival in extrahepatic CCA. Radiologic responses and clinical benefit was noted with EGFR, FGFR, C-met, B-RAF and MEK inhibitors.

Conclusion

There are significant genetic differences between intra and extrahepatic CCA. NGS can potentially identify disease subsets with distinct prognostic and therapeutic implications.  相似文献   

13.
The native gibberellins (GAs) of various organs of the Avena plant were analyzed by bioassay and gas chromatography-mass spectrometry (GC-MS) after silicic acid partition column chromatography. The major GA of the inflorescence was identified as GA3 by GC-MS, and this GA also forms the major component of the nodes, p-1 internode, and roots as determined by GLC or chromatography/bioassay. The inflorescence and nodes are the major sources of native GAs, the last two leaves, internode, and roots having significantly lower amounts of GA-like substances. In the internode, less polar GAs predominated at the lag stage of development, whereas by the log and plateau stages, the more polar GAs increased significantly.  相似文献   

14.
Genomic aberrations (GAs) in fibroblast growth factor receptors (FGFRs) are involved in the pathogenesis of intrahepatic cholangiocarcinoma (ICC), and clinical trials have shown efficacy of FGFR inhibitors in treating ICC patients with FGFR GAs such as FGFR2 rearrangement. To clarify the FGFRs GA profile and corresponding clinicopathological features in Chinese patients with ICC, a total of 257 cases were identified. Fourteen cases (5.45%) were positive for FGFR2 rearrangement. Further analysis on the 110 FGFR2 rearrangement negative cases showed that 13 patients present additional FGFRs GAs, including FGFR3 rearrangement (2.73%), and FGFRs mutations. When compared with patients without FGFRs GAs, those with FGFR2 or FGFR3 rearrangement presented more under the age of 58 years, female sex, HBsAb positivity, CD10 expression, and PD-L1 expression. The clinical characteristics between patients with FGFRs mutation and those without FGFRs GAs were similar, with the exception that cases with FGFRs mutation have more hepatolithiasis. We concluded that FGFR rearrangement is associated with unique clinical phenotypes in ICC.  相似文献   

15.
Sample preparation remains a bottleneck in the rapid and reliable quantification of gibberellins (GAs) for obtaining an insight into the physiological processes mediated by GAs. The challenges arise from not only the extremely low content of GAs in complex plant matrices, but the poor detectability of GAs by mass spectrometry (MS) in negative ion mode. In an effort to solve these urgent difficulties, we present a spatial‐resolved analysis method to investigate the distribution of GAs in tiny plant tissues based on a simplified one‐pot sample preparation approach coupled with ultrahigh‐performance liquid chromatography‐tandem MS. By integrating extraction and derivatization into one step, target GAs were effectively extracted from plant materials and simultaneously reacted with N‐(3‐dimethylaminopropyl)‐N′‐ethylcarbodiimide, the sample preparation time was largely shortened, the probability of sample loss was minimized and the detection sensitivity of MS was also greatly improved compared with underivatized GAs. Under optimal conditions, the method was validated from the quantification linearity, limits of detection and limits of quantification in the presence of plant matrices, recoveries, and precision. With the proposed method, 15 endogenous GAs were detected and, among these, 11 GAs could be quantified in 0.50 mg fresh weight (FW) wheat shoot samples, and five GAs were quantified in only 0.15 mg FW developing seed samples of Arabidopsis thaliana. The distribution patterns of GAs along both the non‐13‐hydroxylation pathway and the early 13‐hydroxylation pathway in a single shoot of germinating wheat, rice and maize seeds were finally profiled with a spatial resolution down to approximately 1 mm2.  相似文献   

16.
Biosynthesis of gibberellins (GAs) was studied in vivo in endosperms of Sechium edule Sw. Exogenous ent-[14C]kaurene was metabolized into four major products: GA12, GA4, GA7 and 16, 17-dihydro-16-hydroxy-GA15 alcohol glucoside. Other minor metabolites were also observed including ent-kaurenol and ent-kaurenal. Conversion of ent-[14C]kaurene to ent-kaurenol glucoside by endosperm cell-free preparations in the presence of UDPG was observed. However, the finding was not confirmed in in vivo studies and is probably artifactual. Overall evidence coming from the analysis of endogenous GAs and in vitro and in vivo biosynthetic studies are discussed in relation to the possible existence in the Sechium seeds of a different route, along with the known pathway, branching from ent-kaurene or ent-7-α-hydroxykaurenoic acid and this also leading to biologically active GAs.  相似文献   

17.
Bioactive gibberellins (GAs) are diterpene plant hormones that are biosynthesized through complex pathways and control diverse aspects of growth and development. GAs were first isolated as metabolites of a fungal rice pathogen, Gibberella fujikuroi, since renamed Fusarium fujikuroi. Although higher plants and the fungus produce structurally identical GAs, significant differences in their GA pathways, enzymes involved and gene regulation became apparent with the identification of GA biosynthetic genes in Arabidopsis thaliana and F. fujikuroi. Recent identifications of GA biosynthetic gene clusters in two other fungi, Phaeosphaeria spp. and Sphaceloma manihoticola, and the high conservation of GA cluster organization in these distantly related fungal species indicate that fungi evolved GA and other diterpene biosynthetic pathways independently from plants. Furthermore, the occurrence of GAs and recent identification of the first GA biosynthetic genes in the bacterium Bradyrhizobium japonicum make it possible to study evolution of GA pathways in general.In this review, we summarize our current understanding of the GA biosynthesis pathway, specifically the genes and enzymes involved as well as gene regulation and localization in the genomes of different fungi and compare it with that in higher and lower plants and bacteria.  相似文献   

18.
The use of nondwarf rice (Oryza sativa L.) cultivars treated with uniconazole as test plants for gibberellin (GA) bioassay instead of Tan-ginbozu dwarf rice variant was investigated. The sensitivity of six nondwarf rice cultivars to GAs was increased substantially by treatment of the seeds with uniconazole. The minimum detectable dose of a GA in the nondwarf cultivars treated with uniconazole was 1- to 1/10-fold of that in the nontreated Tanginbozu and 3- to 10-fold of that in uniconazole-treated Tanginbozu. The relative activity of several GAs on treated nondwarf rice cultivars was not largely different from that to Tan-ginbozu. Considering that seeds of nondwarf rice are available commercially, the nondwarf rice seedling assay would be useful as a simple assay for systematic analysis of GAs, and also as a routine teaching tool in high schools and universities.  相似文献   

19.
The recovery from “lodging,” or bending over, by shoots of 42-day-old Avena sativa plants is controlled primarily by a negatively geotropic differential growth of the lower halves of the p-1 node-pulvinus and the base of the p-1 internode, relative to the upper halves. Although geostimulation causes a significant reduction in p-1 internode length, dry matter accumulation in the p-1 node-pulvinus is increased, apparently at the expense of the sheath. Recovery to an angle of 30° is associated with changes in endogenous gibberellin-like substances (GAs), and in differential metabolism of applied [3H]GA4 (1.4 Curie per millimole). Although geostimulation depressed total GAs (relative to upright plant parts) to 0.40 and 0.13 for node-pulvini and sheaths, respectively, it increased them 2-fold for internodes. Within the plant part geostimulation increased GAs (relative to upper halves) 29- and 7-fold in lower halves of node-pulvini and internodes, respectively, but reduced GAs to 0.3 in lower halves of sheaths. At age 42 days a GA4/7-like (nonpolar) substance predominates, with lesser amounts of a GA3-like (polar) substance. Native GAs of Avena include GA3, GA4, and GA7. Geostimulation enhanced the ratio of nonpolar to polar GAs for both halves of internodes, but tended to depress it for sheaths and nodepulvini.  相似文献   

20.
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