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61.
Chi-Jen Tai Atallah F. Ahmed Chih-Hua Chao Chia-Hung Yen Tsong-Long Hwang Fang-Rong Chang Yusheng M. Huang Jyh-Horng Sheu 《Marine drugs》2022,20(4)
A polyoxygenated and halogenated labdane, spongianol (1); a polyoxygenated steroid, 3β,5α,9α-trihydroxy-24S-ethylcholest-7-en-6-one (2); a rare seven-membered lactone B ring, (22E,24S)-ergosta-7,22-dien-3β,5α-diol-6,5-olide (3); and an α,β-unsaturated fatty acid, (Z)-3-methyl-9-oxodec-2-enoic acid (4) as well as five known compounds, 10-hydroxykahukuene B (5), pacifenol (6), dysidamide (7), 7,7,7-trichloro-3-hydroxy-2,2,6-trimethyl-4-(4,4,4-trichloro-3-methyl-1-oxobu-tylamino)-heptanoic acid methyl ester (8), and the primary metabolite 2’-deoxynucleoside thymidine (9), have been isolated from the Red Sea sponge Spongia sp. The stereoisomer of 3 was discovered in Ganoderma resinaceum, and metabolites 5 and 6, isolated previously from red algae, were characterized unprecedentedly in the sponge. Compounds 7 and 8 have not been found before in the genus Spongia. Compounds 1–9 were also assayed for cytotoxicity as well as antibacterial and anti-inflammatory activities. 相似文献
62.
63.
为了解6种桐籽粕提取物对正常单层鸡胚成纤维细胞(CEF)的毒性作用,以及对鸡新城疫病毒(NDV)体内外抗病毒的作用效果,首先将桐籽粕提取物直接作用于正常的单层CEF,然后将桐籽粕提取物与鸡新城疫病毒37℃作用2 h,分别接种10日龄鸡胚和加入单层CEF。试验结果表明:过NKA 70%醇洗部分,对正常CEF的毒性作用最大,水提物毒性作用最小。而对新城疫病毒,水提物(0.125 m g/m l)的抗病毒效果最好;其次为过NKA大孔吸附树脂30%醇洗部分(0.2 m g/m l),然后依次是水提物(0.5 m g/m l)、水提物(0.25 m g/m l)、无水乙醇析出物(0.2 m g/m l)。 相似文献
64.
65.
Zhengfang Wang Liben Chen Rashad Al-Kasir Bo Han 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(1):27-34
This study assessed the toxicity of melamine against the unicellular eukaryotic system of Tetrahymena (T.) pyriformis exposed to 0, 0.05, 0.25, 0.5, 2.5, and 5 mg/mL of melamine. Cell growth curves of different cultures, the half maximum inhibition concentration (IC50) value of melamine, and morphological changes in cells were obtained via optical and transmission electron microscopic observation. The effects of eleven melamine concentrations, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5 and 5 mg/mL, on protein expression levels of T. pyriformis were examined using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The results showed an obvious inhibitory effect of melamine on the growth of eukaryotic cells. Cell growth dynamics indicated that the IC50 value of melamine on T. pyriformis was 0.82 mg/mL. The cellular morphology was also affected in a concentration-dependent manner, with characteristics of atrophy or cell damage developing in the presence of melamine. The relative contents of the top four main proteins corresponding to peak mass-to-charge ratios (m/z) of 4466, m/z 6455, m/z 6514, and m/z 7772 in the MALDI-TOF-MS spectra were all found to be closely correlated with the melamine concentrations. In conclusion, exposure of eukaryotic cells to melamine could inhibit cell growth, cause changes in cytomorphology and even disturb the expression of proteins in a concentration-dependent manner. The described method of examining four sensitive proteins affected by melamine was also proposed to be used in a preliminary study to identify protein biomarkers in T. pyriformis. 相似文献
66.
Thomas-B. Seiler Andrew Rastall Erik Leist Lothar Erdinger Thomas Braunbeck Henner Hollert 《Journal of Soils and Sediments》2006,6(1):20-29
Goal, Scope and Background Organic solvents are routinely used to extract toxicants from polluted soils and sediments prior to chemical analysis or
bioassay. Conventional extraction methods often require the use of heated organic solvents, in some cases under high pressure.
These conditions can result in loss of volatile compounds from the sample and the degradation of thermally labile target
analytes. Moreover, extracts of soils and sediments also frequently contain substantial quantities of organic macromolecules
which can act as sorbing phases for target analytes and in doing so interfere with both chemical analysis and bioassays.
Membrane dialysis extraction (MDE) is described as a simple, passive extraction method for selectively extracting toxicologically
relevant hydrophobic organic compounds (HOCs) from polluted soils and sediments and anaylzed for its applicability in ecotoxicological
investigations.
Methods Toxicologically relevant hydrophobic organic compounds were extracted from wet and dry sediments by sealing replicate samples
in individual lengths of pre-cleaned low-density polyethylene (LD-PE) tubing and then dialysing in n-hexane. The efficacy
of the MDE method for use in ecotoxicological investigations was assessed by testing the concentrated extracts in the neutral
red assay for acute cytotoxicity, in the EROD assay for the presence of dioxin-like compounds and in the Danio rerio fish
egg assay for embryotoxic and teratogenic effects. Conditions of the sediment sample (with or without water content), dialysis
membrane length and duration of dialysis were analyzed with respect to their impact on three endpoints. Results of the MDE
investigations were compared to data obtained in samples prepared using conventional Soxhlet extraction.
Results and Discussion The membrane dialysis extraction was found to be at least as efficient as Soxhlet methodology to extract toxicologically
relevant HOCs from sediment samples. In most cases, MDE-derived extracts showed a higher toxicological potential than the
Soxhlet extracts. Lack of any significant effects in any MDE controls indicated these differences were not caused by contamination
of the LD-PE membrane used. The elevated toxicological potential of MDE extracts is most likely the result of enhanced bioavailability
of toxic compounds in consequence of lower amounts of organic macromolecules (i.e. sorbing phases) in the MDE extracts.
This effect is probably the result of a size-selective restriction by the LD-PE membrane.
Conclusion Membrane dialysis extraction was found to be a simple, efficient and cost-effective method for the extraction of sediment
samples. MDE can be used to extract toxicologically relevant hydrophobic organic compounds from both wet and dry sediments
without the risk of loosing volatile and thermally labile target analytes. The size-selectivity of the LD-PE membrane also
appears to have the capacity to increase the bioavailablity of potential target analytes in the resulting extracts by retaining
much of the organic macromolecules present in the sample. Thus, results suggest that MDE may be particularly useful for
the extraction of toxicologically relevant hydrophobic organic compounds from soils and sediments for bioassays and other
ecotoxicological investigations.
Recommendation and Perspective Further validation of MDE has been initiated and the applicability of the methodology to other sample types will be investigated.
Of particular interest is the potential application of MDE to recover hydrophobic target analytes from biological samples
such as muscle, other soft tissues and blood. 相似文献
67.
Leucocytes derived from head kidney, blood and spleen of turbot, Scophthalmus maximus (L.), exhibited cytotoxic activities against an established cell line (RTG-2) derived from rainbow trout, Oncorhynchus mykiss (Walbaum). The optimal effector:target ratio, temperature and incubation period for the activity was determined. Cytotoxicity was not caused by released factors, as effector:target contact was needed. Visualization of the cultures under the transmission electron microscope corroborated the contact between leucocytes and target cells and suggested the implication of monocyte-like cells in this cell-mediated cytotoxicity. 相似文献
68.
M. Vazzana M. Cammarata E. L. Cooper N. Parrinello 《Aquaculture (Amsterdam, Netherlands)》2002,210(1-4):231-243
Fish respond to stressful conditions via neuroendocrine responses (primary response) which result in increased levels of plasma cortisol which is considered immunosuppressive. Sea bass were confined at low (10 kg/m3) and high (60 kg/m3) density for 3–48 h. Plasma cortisol and glucose were evaluated and two principal cellular immune responses were assayed. A significant increase in plasma cortisol and glucose levels, as well as osmolarity, was found following stress. In addition, phagocytic activity, as shown by reactive oxygen species (ROS) production by challenged head kidney phagocytes and cytotoxic activity of eosinophilic granule cells from peritoneal cavity against K562 tumour cell lines appeared to be suppressed. Plasma levels of cortisol, glucose, osmolarity were correlated with cellular immunity, by the linear regression method. The suppression of cytotoxic activity was found to be significantly correlated with high plasma cortisol and glucose levels. These parameters could affect the eosinophilic granule cells of the peritoneal cavity. 相似文献
69.
Anthraquinones are an interesting chemical class of polyketides since they not only exhibit a myriad of biological activities but also contribute to managing ecological roles. In this review article, we provide a current knowledge on the anthraquinoids reported from marine-derived fungi, isolated from various resources in both shallow waters such as mangrove plants and sediments of the mangrove habitat, coral reef, algae, sponges, and deep sea. This review also tentatively categorizes anthraquinone metabolites from the simplest to the most complicated scaffolds such as conjugated xanthone–anthraquinone derivatives and bianthraquinones, which have been isolated from marine-derived fungi, especially from the genera Apergillus, Penicillium, Eurotium, Altenaria, Fusarium, Stemphylium, Trichoderma, Acremonium, and other fungal strains. The present review, covering a range from 2000 to 2021, was elaborated through a comprehensive literature search using the following databases: ACS publications, Elsevier, Taylor and Francis, Wiley Online Library, MDPI, Springer, and Thieme. Thereupon, we have summarized and categorized 296 anthraquinones and their derivatives, some of which showed a variety of biological properties such as enzyme inhibition, antibacterial, antifungal, antiviral, antitubercular (against Mycobacterium tuberculosis), cytotoxic, anti-inflammatory, antifouling, and antioxidant activities. In addition, proposed biogenetic pathways of some anthraquinone derivatives are also discussed. 相似文献
70.
棉铃虫Helicoverpa armigera是世界性重要农业害虫。目前防治棉铃虫的主要手段是种植转苏云金芽胞杆菌Bacillus thuringiensis(Bt)杀虫蛋白的转基因作物。本文旨在研究棉铃虫V-ATPase H在Cry1Ac蛋白毒力和抗性中的作用。利用实时荧光定量qRT-PCR技术分析V-ATPase H在Cry1Ac抗、感品系棉铃虫幼虫中肠及敏感品系棉铃虫幼虫受Cry1Ac诱导后的表达情况;在昆虫Sf9细胞中过表达V-ATPase H对其进行细胞定位,通过细胞毒力试验验证其对Cry1Ac毒力的影响。结果发现棉铃虫V-ATPase H基因在抗性品系中低表达,并且V-ATPase H在受到Cry1Ac诱导时也低表达;在Sf9细胞内表达V-ATPase H蛋白发现其在整个细胞中都有分布,过表达该蛋白后增强了细胞对Cry1Ac蛋白的敏感性。结果表明V-ATPase H参与Cry1Ac蛋白的毒力。 相似文献