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The usefulness of benthic multi-metric indices when assessing seafloor integrity across broad environmental gradients should be deliberated, as their lack of transparency might hide important sources of variation and fail to identify environmental change. This study compares the performance of two multi-metric indices; the Benthic Quality Index (BQI) and the Brackish water Benthic Index (BBI) between three sub-basins in the Baltic Sea. Both indices reflect the salinity-driven gradient in macroinvertebrate diversity and composition as well as changes in bottom water oxygen concentrations. The relative contribution of predictor variables for explaining index variation does, however, differ between sub-basins, resulting in the indices representing different aspects of the benthic community along the environmental gradient. This context-dependency is caused by inherent differences in benthic community characteristics between the sub-basins of the Baltic Sea, and how the communities are portrayed by the indices. An increased transparency of the importance of the different predictors for directing index values is needed for coherent classifications over broad environmental gradients, such as those occurring in large estuarine water bodies. Use of a weight of evidence table to combine multiple indicators would preserve transparency and be more likely to provide a robust assessment method that would detect seafloor degradation at an early stage. 相似文献
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Vladimir Jirkû 《Antonie van Leeuwenhoek》1997,71(4):369-373
Covalent attachment of Candida utilis cells, possibly simulating natural microbial immobilizations, stimulated stable and significant enhancement of extracellular production of alkaline protease, specifically induced by four different starvation conditions. The enzyme analysis confirmed the identity of the proteases released under all conditions of starvation and no parallel production of other proteolytic enzyme. The enhancement phenomenon as a uniform and stable effect of the whole cell immobilization is discussed in relation to the effect of multipoint, cell-solid surface contact, potentially bringing positive modulations of complex, cellular functions. 相似文献
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Botrytis allii andCollectotrichum dematium are onion pathogens which can infect in the field and cause decay in storage. Some phenolics can hinder development of these fungi, but the effect of cytokinins is not clear. Cytokinins (kinetin or 6-benzyladenine) or phenolics (caffeic or chlorogenic acids) were added to agar at concentrations of 0 to 10–3 M. Cultures were continuously irradiated with fluorescent light or maintained in the dark for 6 days. On unamended media, final mycelial elongation was 45 or 17.8 mm and sporulation was 28 or 10.6 × 104 spores/ml forBotrytis andColletotrichum, respectively. ForBotrytis, mycelial elongation was slightly (5%) but significantly increased and sporulation increased by 21% by incubation on phenolics as compared to cytokinins. Mycelial extension ofColletotrichum was not affected by amendment. Sporulation ofColletotrichum on kinetin was 16 to 28% greater than on the other amendments. As amendments concentration increased elongation of mycelia of both fungi decreased. Sporulation ofBotrytis increased by 60% as amendment concentration increased from 0 to 10–5 M and then decreased 25% at 10–3 M. As amendment concentration increased from 0 to 10–3 M, sporulation ofColletotrichum increased by 45%. Incubation in light increased mycelial extension 3 to 17% forBotrytis andColletotrichum respectively, and sporulation was increased approximately 78% for both fungi. These compounds do not appear to inhibit development of theseBotrytis orColletotrichum species in culture. 相似文献
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Four classes of Xanthomonas campestris mutants were identified with respect to pectate lyase. Pectate lyase production in the wild-type and classes I and IIb mutants was partially dependent on the growth-phase whereas in classes IIa and III it was totally dependent. Enzyme activity in some of the mutants was constitutive and resistant to catabolite repression. 相似文献
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Serum samples of Meishan (13 animals) and Meishan x Wild Boar crosses (361 animals) were analysed by means of two-dimensional electrophoresis. Some new variants in protease inhibitor systems PO1A, PO1B and PI2 are reported. 相似文献
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《Bioorganic & medicinal chemistry》2020,28(22):115739
N-phenyl ureidobenzenesulfonates (PUB-SOs) is a new class of promising anticancer agents inducing replication stresses and cell cycle arrest in S-phase. However, the pharmacological target of PUB-SOs was still unidentified. Consequently, the objective of the present study was to identify and confirm the pharmacological target of the prototypical PUB-SO named 2-ethylphenyl 4-(3-ethylureido)benzenesulfonate (SFOM-0046) leading to the cell cycle arrest in S-phase. The antiproliferative and the cytotoxic activities of SFOM-0046 were characterized using the NCI-60 screening program and its fingerprint was analyzed by COMPARE algorithm. Then, human dihydroorotate dehydrogenase (hDHODH) colorimetric assay, uridine rescuing cell proliferation and molecular docking in the brequinar-binding site were performed. As a result, SFOM-0046 exhibited a mean antiproliferative activity of 3.5 μM in the NCI-60 screening program and evidenced that leukemia and colon cancer cell panels were more sensitive to SFOM-0046. COMPARE algorithm showed that the SFOM-0046 cytotoxic profile is equivalent to the ones of brequinar and dichloroallyl lawsone, two inhibitors of hDHODH. SFOM-0046 inhibited the hDHODH in the low nanomolar range (IC50 = 72 nM) and uridine rescued the cell proliferation of HT-29, HT-1080, M21 and MCF-7 cancer cell lines in the presence of SFOM-0046. Finally, molecular docking showed a binding pose of SFOM-0046 interacting with Met43 and Phe62 present in the brequinar-binding site. In conclusion, PUB-SOs and notably SFOM-0046 are new small molecules hDHODH inhibitors triggering replication stresses and S-phase arrest. 相似文献
9.
The genera Leontodon s.str. and Hedypnois are so far the only known sources of hydroxyhypocretenolides, a rare subclass of guaianolide type sesquiterpene lactones. In this study the three endemic species from the Azorean Archipelago, L. filii, L. hochstetteri, and L. rigens, were analyzed together with L. hispidus and L. × grassiorum, a hybrid originating from L. hispidus and L. hochstetteri. Flowering heads were analyzed by UHPLC-DAD-MS with regards to their phenolics' profiles, establishing qualitatively identical profiles for all taxa. The following phenolics were detected in flowering heads of all investigated taxa: caffeoyltartaric acid, cichoric acid, chlorogenic acid, 3,5-di-O-caffeoylquinic acid, luteolin, luteolin 7-O-β-d-glucopyranoside, luteolin 4′-O-β-d-glucopyranoside, and luteolin 7-O-β-d-glucuronide.In UHPLC-DAD-MS analyses of the rhizomes, no flavonoids were detected. In rhizomes, caffeoyltartaric acid was only detected in L. hispidus. However, in addition to caffeoylquinic acid derivatives already found in the flowering heads, 1,5-di-O-caffeoylquinic acid, 3,4-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid were detected in rhizomes of all investigated taxa.The chemophenetically most interesting group of hydroxyhypocretenolides was detected in rhizomes of all investigated taxa. 11,13β-Dihydro-14-dihydroxyhypocretenolide was detected in L. filii and L. hochstetteri, while 11,13β-dihydro-14-hydroxyhypocretenolide-β-d-glucopyranoside was present in all Azorean taxa. 1,10-Epoxy-14-hydroxyhypocretenolide-β-d-glucopyranoside and 1,10-epoxy-14-hydroxyhypocretenolide-β-d-glucopyranoside-6′-O-p-hydroxyphenylacetic acid ester were restricted to the Azorean taxa and the hybrid L. × grassiorum, while the dimeric sesquiterpenoid 14-hydroxyhypocretenolide-β-d-glucopyranoside-4′,14″-hydroxyhypocretenoate ester was restricted to L. hispidus and L. × grassiorum. 相似文献
10.
Two new compounds, named leptospyranonaphthazarin A (1) and leptosnaphthoic acid A (2), together with four known compounds (3–6) were isolated from an endophytic fungus Leptosphaerulina sp. SKS032. Their structures were assigned using spectroscopic methods, computational methods, and single-crystal X-ray diffraction analysis. In the antibiotic assay, compounds 1, 2, and 6 exhibited antibacterial activities against Staphylococcus aureus with minimal inhibitory concentration (MIC) values of 25.0, 50.0, and 50.0 μg/mL, respectively. 相似文献