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1.
In order to discriminate between the ionic and osmotic components of salt stress, sugarcane (Saccharum officinarum L. cv. Co 86032) calli were cultured on media containing NaCl or polyethylene glycol (PEG) 8000 that exerted the same osmotic pressure (−0.7 MPa). PEG stress exposure for 15 days led to significant growth reduction and loss in water content than salt stressed and control tissues. Osmotic adjustment (OA) was observed in callus tissues grown on salt, but was not evident in callus grown on PEG. Oxidative damage to membranes, estimated in terms of accumulation of thiobarbituric acid reactive substances-TBARS and electrolytic leakage was significantly higher in both the stressed calli than the control however, the extent of damage was more in the PEG stressed calli. The stressed callus tissues showed inhibition of ascorbate peroxidase activity, while catalase activity was increased. These results indicate sensitivity of cells to PEG-mediated stress than salt stress and differences in their OA to these two stress conditions. The sensitivity to the osmotic stress indicate that expression of the stress tolerance response requires the coordinated action of different tissues in a plant and hence was not expressed at the cellular level.  相似文献   
2.
Summary Low molecular weight iron-binding compounds are produced by the brown-rot fungus Gloeophyllum trabeum. These chelators may function in scavenging transition metals for fungal metabolism and extracellular enzyme production. Because of the low molecular mass of the chelate-metal complex (below 1000 Da), and the oxidizing potential of the bound transition metals, certain chelating compounds could also play a role in the early stages of cellulose depolymerization by brown-rot fungi. High-affinity iron-binding compounds were isolated and partially purified from both liquid cultures of the brown-rot Gloeophyllum trabeum and from infected wood. Chelating compounds purified by thin-layer chromatography were used to prepare specific antibodies. These antibodies were shown to detect the chelator in infected wood and liquid fungal cultures by enzyme-linked immunosorbent assay and could be used in immunotransmission electron microscopy to visualize the high-affinity iron-binding compounds in situ. Elucidating the physiological roles of fungal chelate-metal complexes and determining their function in lignocellulose depolymerization will help us to better understand the mechanism of wood biodegradation.Publication no. 1549 Maine Agricultural Experiment Station Offprint requests to: J. Jellison  相似文献   
3.
The aim of current work was to determine essential oils (EOs) composition from three Eucalyptus species, including E. citriodora, E. camaldulensis and E. globulus and assess their α-glucosidase inhibitory activity. The EOs were collected using the hydrodistillation technique and characterized by GC/MS, GC-FID and NMR. The isolated EOs from leaves parts of Eucalyptus species varied from 0.56 to 1.0 % on fresh weight basis. The content of the EOs was distinct according to the species. The most abundant metabolites were identified as citronellal (0–83.0 %), 1,8-cineole (0.2–44.8 %), spathulenol (0.4–16.1 %) α-pinene (0.4–15.9 %), p-cymene (3.7–11.9 %), citronellol (0–8.6 %), β-eudesmol (5.3–8.6 %) and β-pinene (0–7.1 %). The EOs obtained from targeted samples exhibited strong α-glucosidase inhibitory activity. These results are encouraging and underline that the EOs of Eucalyptus species may be a promising alternative source of natural antidiabetic.  相似文献   
4.
Summary Mass cultivation of Spirulina for commercial application suffers from poor productivity when measured against laboratory results or theoretical projections. Wider applications of algal products require that this gap be reduced. Addition of eucalyptus kraft black liquor at a maximum of 0.1% to Spirulina cultures enhanced biomass productivity by at least 40%. The factors enhancing Spirulina biomass productivity were insoluble at low pH, of low molecular mass and stable to high temperature. Single addition of kraft black liquor in outdoor continuous cultures afforded sustained enhancement in biomass productivity for at least eight weeks.  相似文献   
5.
The present work deals with the effect of some auxins [2,4-D,IAA, NAA and ß-naphthoxyacetic acid (NOA)] and cytokinins[6-benzylaminopurine (BAP), 6-(,-dimethylallylamino)purinc (2iP),KN and 6-(4-hydroxy-3-methylbut-2-enylaimno)purine (zeatin)]on growth and gametangial formation in the liverwort Ricciagangetica. Of these, 2,4-D and IAA stimulate vegetative growth,induce the formation of rhizoids on dorsal surface of thallusand shorten the time required for gametangial initiation. NAAand NOA inhibit growth, and do not affect the time of gametangialproduction. The auxins increase archegonial number without affectingantheridial induction and, among those tested, IAA is the mosteffective. Archegonial number is enhanced by the cytokinins,but antheridial production decreases. The maximum number ofarchegonia is initiated in response to 2iP, and this effectappears to be specific. On the other hand, thallus growth, stimulatedby the other cytokinins, is inhibited by 2iP. Riccia gangetica Ahmad, liverwort, auxins, cytokinins, growth, gametangial, formation  相似文献   
6.
The purine analogs 8-azaadenine, 8-azaguanine, 4-aminopyrazolo [3,4-d] pyrimidine, 2-fluoroadenine and 6-methylpurine inhibited bud burst in non-dormant vegetative axillary bud explants obtained from apple (Malus domestica Borkh.) seedlings. The reversal of inhibition was attempted by incorporating increasing concentrations of benzyladenine (BA) in the culture medium. The inhibition caused by 8-azaadenine and 8-azaguanine was reduced especially when BA was added to the media at equimolar ratios along with the inhibitors. The inhibition due to 4-aminopyrazolo [3,4-d] pyridine was reduced only with equimolar BA, BA was ineffective or only minimally effective in reducing inhibition due to 2-fluoroadenine and 6-methypurine. Short pretreatment with 8-azaadenine and 8-azaguinine failed to cause any inhibition when explants were subsequently transferred to BA -containing medium. The effectiveness of 2-fluoroadenine and 6-methylpurine was maintained or only slightly reduced, indicating their long-term inhibitory action.  相似文献   
7.
International Journal of Peptide Research and Therapeutics - Bioactive peptides have been reported to exhibit opioid-like activity and are termed as opioid peptides. Either these are produced...  相似文献   
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9.
The recent outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has impacted the world severely. The binding of the SARS-CoV-2 virus to the angiotensin-converting enzyme 2 (ACE2) and its intake by the host cell is a necessary step for infection. ACE2 has garnered widespread therapeutic possibility as it is entry/interactive point for SARS-CoV-2, responsible for coronavirus disease 2019 (COVID-19) pandemic and providing a critical regulator for immune modulation in various disease. Patients with suffering from cancer always being on the verge of being immune compromised therefore gaining knowledge about how SARS-CoV-2 viruses affecting immune cells in human cancers will provides us new opportunities for preventing or treating virus-associated cancers. Despite COVID-19 pandemic got center stage at present time, however very little research being explores, which increase our knowledge in context with how SARS-CoV-2 infection affect cancer a cellular level. Therefore, in light of the ACE-2 as an important contributor of COVID-19 global, we analyzed correlation between ACE2 and tumor immune infiltration (TIL) level and the type markers of immune cells were investigated in breast cancer subtypes by using TIMER database. Our findings shed light on the immunomodulatory role of ACE2 in the luminal A subtype which may play crucial role in imparting therapeutic resistance in this cancer subtype.  相似文献   
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