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1.
A simple and easy protocol for extracting high-quality DNA from different yeast and filamentous fungal species is described. This method involves two important steps: first, the disruption of cell walls by mechanical means and freezing; and second, the extraction, isolation, and precipitation of genomic DNA. The absorbance ratios (A260/A280) obtained ranged from 1.6 to 2.0. The main objective of this procedure is to extract pure DNA from yeast and filamentous fungi, including those with high contents of proteins, polysaccharides, and other complex compounds in their cell walls. The yield and quality of the DNAs obtained were suitable for micro/minisatellite primer-polymerase chain reaction (MSP-PCR) fingerprinting as well as for the sequence of the D1/D2 domain of the 26S rDNA.  相似文献   

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This work demonstrates the significant differences in ethanol production of two henequen (Agave fourcroydes Lem) varieties. Yaax ki, or green henequen, surpasses Sac ki, or white henequen, in weight, sugar accumulation capability and ethanol production. The study was carried out with the ‘piña’ (stem and basal part of the leaves that remain attached to it after harvesting the leaves) of 5‐ and 9‐year‐old plants, cultivated in two localities of Yucatán, México. At 5 years of age, Yaax ki piñas are 33% larger than those of Sac ki, and at 9 years this difference can increase to 59%. Juice from 5‐year‐old piñas of Yaax ki contains 15.6% more reducing sugars, whereas in the must it can exceed 67%. Values obtained in the 9‐year‐old plants indicate that the Yaax ki variety accumulates 30.6% more reducing sugars than the Sac ki, whereas in the must the difference is in favor of Yaax ki is 21.7%. To produce 1 L of ethanol at 40% concentration by volume from 5‐year‐old plants, 48 kg of Sac ki piñas and 29 kg of Yaax ki are required, whereas with the 9‐year‐old plants, only 23 and 19 kg are needed, respectively.  相似文献   

4.
Three novel spirostanol-type (2, 3, and 5) and a furostanol-type (4) steroidal saponins were isolated from the stems of Calamus insignis (Palmae), along with a known steroidal saponin (1) by bioassay guided purification. The chemical structures of 1-5 were established on the basis of spectroscopic analysis and the result of acidic hydrolysis. Compounds 1, 2, 3, and 5 showed cell growth inhibitory activity against HeLa cells at a concentration of less than 10 microM, and 1 exhibited a cell cycle inhibitory effect at the G2/M stage at concentrations of 1.5 and 2.9 microM by flow cytometric analysis. This effect seems to be correlated with large expression of p21 and inhibition of dephosphorylation of cdc2 according to the result of Western blotting analysis.  相似文献   

5.
Phytochemical investigation on Drypetes hainanensis has resulted in the isolation of three new phenylpropanoids, named drypetesins A–C (13). Their structures were elucidated by applying various spectroscopic techniques (NMR, UV, IR, MS, and CD). The antiproliferative activities of these compounds were evaluated in vitro against three cultured cancer cell lines. Those new isolates exhibited potent cytotoxic activities against human hepatoma (HepG2), human breast adenocarcinoma (MCF-7), and human lung carcinoma (A-549) cancer cell lines with IC50 value range 5.6–14.8 μM.  相似文献   

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Two new synthetic analogues of luotonins A and F, 7-acetylaminoluotonin A (6) and 3-[3H(quinazolino-4-one)]quinoline (7) were synthesized. The new analogues, along with four natural quinazoline-quinoline alkaloids, luotonins A (1), B (2), E (3), F (4) and a synthetic deoxoluotonin F (5), showed cytotoxic activity (IC(50) 1.8-40.0 microg/mL) and DNA topoisomerase II inhibition at a concentration of 25 microM.  相似文献   

9.
6-Deoxyclitoriacetal (1) and a series of 11 further derivatives of it (2-12) were synthesized and evaluated for their cytotoxic and topoisomerase IIα inhibitory activities. Compounds bearing epoxide (2), morpholine (6) and benzylamine (10) moieties showed promising in vitro cytotoxic activities against four cancer cell lines, with IC50 values ranging from 0.38 to 0.73 μM. These three compounds also strongly inhibited topoisomerase II activity at 68.3-93.5% and showed a moderately high DNA intercalating property.  相似文献   

10.
Eight new iridal-type triterpenoid derivatives, including two noriridals with ether bridge (12); two iridals lactone (34), four monocyclic iridals (58), together with five known iridals (914) were identified from the rhizome of Belamcanda chinensis. Their structures were elucidated on the basis of comprehensive spectroscopic methods and electronic circular dichroism (ECD) calculations. Bioassay results showed that belamcanoxide B (1) exhibited moderated cytotoxic activities against HCT-116 and MCF-7 cell lines with IC50 values of 5.58 and 3.35 μM.  相似文献   

11.
Twelve highly oxygenated novel daphnane-type diterpenoids genkwanines A-L (1-12), together with four known diterpenes (13-16), were isolated from the bud of Daphne genkwa, a well-known traditional Chinese medicine (TCM). The new structures were elucidated on the basis of spectral methods, especially 2D NMR spectra (HMQC, HMBC, NOESY). Inhibitory activity against endothelium cell HMEC proliferation and cytotoxic activities against two tumor cell lines were assessed for all the compounds 1-16, and found to be significant and structure related. A number of compounds showed very potent cytotoxic activities against two tumor cell lines at the IC50 levels of 0.15-8.40 microM, and most interestingly, five of the compounds 4, 8, 10, 13, and 14 exhibited strong activity to inhibit the endothelium cell HMEC at the IC50 levels of 2.90-15.0 microM.  相似文献   

12.
In the fermentation process of henequen (Agave fourcroydes Lem.) leaf juice, complemented with industrial molasses, the use of an inoculum comprising two yeasts: Kluyveromyces marxianus (isolated from the henequen plant) and Saccharomyces cerevisiae (commercial strain) was studied. An ethanol production of 5.22+/-1.087% v/v was obtained. Contrary to expected, a decrease on ethanol production was observed with the use of the K. marxianus strain. The best results were obtained when a mixture of 25% K. marxianus and 75% S. cerevisiae or S. cerevisiae alone were used with an initial inoculum concentration of 3x10(7)cellmL(-1). Furthermore, it was possible to detect a final concentration of approximately 2-4gL(-1) of reducing sugars that are not metabolized by the yeasts for the ethanol production. These results show that although the use of a mixture of yeasts can be of interest for the production of alcoholic beverages, it can be the opposite in the case of ethanol production for industrial purposes where manipulation of two strains can raise the production costs.  相似文献   

13.
The Nobel environmental productivity index (EPI) was used as a framework for the development of a predictive geospatial model to estimate the bioethanol yield potential of four crassulacean acid metabolism (CAM) candidates in Australia (Agave fourcroydes, Agave salmiana, Agave tequilana, and Opuntia ficus‐indica). GIS software was used to integrate climate datasets with titratable acidity responses to changes in photosynthetically active radiation (PAR), temperature, and water availability. Additional refinements to Nobel's approach were made to accommodate spatial and temporal fluctuations in soil water potential (ψs) as a function of soil particle size distribution and precipitation, and CO2 uptake response to a range of day and night temperatures. A scalar factor for CO2 persistence during periods of drought was also introduced to model the capacity of succulent species of Agave to buffer against fluctuations in ψs. Macro‐scale criteria were applied to estimate environmentally responsible (ER) bioethanol yield potential on lands that are not suitable for food production. Consideration was given to indigenous vascular plant species richness and endemism scores at ER sites of interest. The highest mean ER bioethanol yield was achieved by A. fourcroydes (μ: 3.89, max. 7.17 kL ha‐1 yr‐1) while the highest maximum yield was achieved by A. tequilana (μ: 3.78, max. 7.63 kL ha‐1 yr‐1). This research indicated the CAM pathway may produce significant yields (≥≥ 5 kL ha‐1 yr‐1) at ER sites totalling 57,700 km2 (0.7% land area of Australia).  相似文献   

14.
Two half-sandwich cobalt and rhodium complexes 2a and 2b with combination of carborane and N-Sulfonamide were synthesized and fully characterized by NMR spectroscopy, mass spectrometry, elemental analysis as well as X-ray crystallography. In an in vitro cytotoxicity assay toward the non-small cell lung cancer cell lines of A549 and NCI-H460, 2b showed the stronger activity than 2a, which was confirmed by the morphological test. Mechanistic studies for 2b showed that inhibition of NSCLC cell growth was mediated by G0/G1 cell cycle arrested without the significant apoptosis induction. Furthermore, 2b altered the mRNA levels of CCND1, CCNE1 and PCNA, which were known to control G0/G1 phase of the cell cycle. Our western blot analysis also showed that 2b-induced G0/G1 cell cycle arrest was mediated through the decreased expression of cyclin D1, cyclin E1 and PCNA.  相似文献   

15.
Two cathepsin B inhibitors were isolated from the culture supernatant of a marine Pseudomonas sp. PB01 (GenBank Accession No. EU126129). Their structures were elucidated by spectroscopic analyses as dibutyl phthalate and di-(2-ethylhexyl) phthalate. Both dibutyl phthalate and di-(2-ethylhexyl) phthalate showed dose-dependent cathepsin B inhibitions with IC(50) of 0.42 and 0.38 mM, respectively. It is also observed from kinetic analyses that dibutyl phthalate and di-(2-ethylhexyl) phthalate acted as noncompetitive inhibitors with K(i) values of 0.64 and 0.42 mM, respectively. Furthermore, both of them caused inactivation of the pericellular cathepsin B of murine melanoma cell with no acute cytotoxicity. The IC(50) values were found to be 0.23 mM for dibutyl phthalate and 0.14 mM for di-(2-ethylhexyl) phthalate, respectively, and were 50% compared to that of purified cathepsin B.  相似文献   

16.
Five flavonols (3, 5, and 911) were isolated from Rhodiola rosea, and compared with commercially available flavonoids (1, 2, 4, 68, and 1214) to facilitate analysis of their structure–activity relationship (SAR). All compounds (114) showed neuraminidase inhibitory activities with IC50 values ranging from 0.8 to 56.9 μM. The in vitro anti-influenza virus activities of flavonoids 16, 812, and 14 were evaluated using two influenza viral strains, H1N1 (A/PR/8/34) and H9N2 (A/Chicken/Korea/MS96/96), testing their ability to reduce virus-induced cytopathic effect (CPE) in MDCK cells. We found that the activity of these compounds ranged from 30.2 to 99.1 μM against H1N1- and 18.5 to 133.6 μM against H9N2-induced CPE. Of compounds 114, gossypetin (6) exhibited the most potent inhibitory activity, with IC50 values of 0.8 and 2.6 μM on neuraminidases from Clostridium perfringens and recombinant influenza virus A (rvH1N1), respectively. In contrast, kaempferol (3) exhibited the highest activity against two influenza viruses, H1N1 and H9N2 with EC50 values of 30.2 and 18.5 μM, respectively. Activity depended on the position and number of hydroxy groups on the flavonoids backbone. In kinetic studies, all isolated compounds behaved as noncompetitive inhibitors.  相似文献   

17.
Four new daphnane-type diterpenes, genkwadanes A–D (14), together with 19 known ones, were isolated from ethanol extract of the flower buds of Daphne genkwa. Their structures were determined on the basis of extensive spectroscopic data. Among them, daphnane-type diterpene with a 1,10-double bond (1) was isolated from this plant for the first time. The cytotoxicity of all compounds 123 against the 10 selected human cancer cell lines was assayed. A number of compounds exhibited significant activities against the 10 cancer cell lines (IC50 < 9.56 μM). and most interestingly, all the compounds revealed preferred cytotoxicities on the HT-1080 cell line and displayed much stronger inhibitory activities (IC50 < 29.94 μM) compared with positive control 5-fluorouracil (IC50 = 35.62 μM), particularly, compounds 911, 13, 16 and 19 exhibited the strongest cytotoxicity activities against the HT-1080 cell line (IC50 < 0.1 μM).  相似文献   

18.
Biscoumarin derivatives 1-27 were tested for their inhibition of snake venom and human nucleotide pyrophosphatase phosphodiesterase-1 enzymes. Lineweaver-Burk and Dixon plots and their secondary replots showed that these compounds are pure non-competitive inhibitors of both the enzymes. Ki and IC50 values of biscoumarins were found to be in the range of 50 to 1000 and 164 to > 1000 microM, respectively, against human recombinant phosphodiesterase 1 enzyme and 8.0 to 1150 and 9.44 to > 1000 microM, respectively, against snake venom phosphodiesterase. Compounds 1, 3, 4, 6, 7, 17, 26, and 30 were found to be non-competitive and non-cytotoxic upto a concentration of 200 microg/mL as evident by less than 10% cell death after 3 h of incubation.  相似文献   

19.
Two new bisindole alkaloids, 6-hydroxystaurosporinone (1) and 5,6-dihydroxyarcyriaflavin A (2) were isolated from field-collected fruit bodies of a myxomycete Lycogala epidendrum, along with eight known bisindoles (3-10). The structures of these new compounds were determined on the basis of spectroscopic data. Compounds 1 and 2 showed cytotoxicity against HeLa, Jurkat, and vincristine resistant KB/VJ300 cells, and compound 1, particularly, inhibited protein tyrosine kinase activity.  相似文献   

20.
Dai SJ  Tao JY  Liu K  Jiang YT  Shen L 《Phytochemistry》2006,67(13):1326-1330
Three neo-clerodane diterpenoids, named barbatins A-C (1-3), and the neo-clerodane diterpenoid nicotinyl ester, named scutebarbatine B (4), were isolated from the whole plant of Scutellaria barbata D. Don. Their structures were elucidated by spectroscopic analyses (UV, IR, HRFAB-MS, 1D NMR and 2D NMR). In vitro, compounds 1-4 showed significant cytotoxic activities against three human cancer lines, namely, HONE-1 nasopharyngeal, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells, with IC50 values in the range 3.5-8.1 microM.  相似文献   

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