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Kumar Narendra Kumari Vandna Ram Chand Thakur Kiran Tomar Sudhir Kumar 《Applied microbiology and biotechnology》2018,102(4):1599-1615
Applied Microbiology and Biotechnology - Foodstuffs and water are the key sources of cadmium biomagnifiaction. The available strategies to mitigate this problem are unproductive and expensive for... 相似文献
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Free radicals can be scavenged from biological systems by genistein, daidzein, and their methyl derivatives through hydrogen atom transfer (HAT), single-electron transfer (SET), and sequential proton-loss electron-transfer (SPLET) mechanisms. Reactions between these derivatives and the free radicals OH., OCH3., and NO2. via the HAT mechanism in the gas phase were studied using the transition state theory within the framework of DFT. Solvation of all the species and complexes involved in the HAT reactions in aqueous media was treated by performing single point energy calculations using the polarizable continuum model (PCM). The SET and SPLET mechanisms for the above reactions were also considered by applying the Marcus theory of electron transfer, and were found to be quite sensitive to geometry and solvation. Therefore, the geometries of all the species involved in the SET and SPLET mechanisms were fully optimized in aqueous media. The calculated barrier energies and rate constants of the HAT-based scavenging reactions showed that the OH group of the B ring in genistein, daidzein, and their methyl derivatives plays a major role in the scavenging of free radicals, and the role of this OH group in the HAT-based free-radical scavenging decreases in the following order: OH.?>?OCH3. > NO2.. The SPLET mechanism was found to be an important mechanism in these free-radical scavenging reactions, whereas the SET mechanism was not important in this context. 相似文献
64.
Singh Rajendra Pandey Deepak Devi Neena Chand Duni 《Bioprocess and biosystems engineering》2018,41(8):1225-1232
Bioprocess and Biosystems Engineering - Butyramide is a commodity chemical having wide range of applications from material science to biological sciences including synthesis of therapeutic drugs,... 相似文献
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Bharat Nareshkumar Shaik Mohammad Akbar Hari Chand Sharma Senigala K. Jayalakshmi Kuruba Sreeramulu 《Journal of bioenergetics and biomembranes》2018,50(1):21-32
Neonicotinoids have high agonistic affinity to insect nicotinic acetylcholine receptors (nAChR) and are frequently used as insecticides against most devastating lepidopteran insect pests. Imidacloprid influenced dose-dependent decline in the state III and IV respiration, respiration control index (RCI), and P/O ratios, in vitro and in vivo. The bioassay indicated its LD50 value to be 531.24 μM. The insecticide exhibited a dose-dependent inhibition on F0F1-ATPase and complex IV activity. At 600 μM, the insecticide inhibited 83.62 and 27.13% of F0F1-ATPase and complex IV activity, respectively, and induced the release of 0.26 nmoles/min/mg protein of cytochrome c. A significant dose- and time-dependent increase in oxidative stress was observed; at 600 μM, the insecticide correspondingly induced lipid peroxidation, LDH activity, and accumulation of H2O2 content by 83.33, 31.51 and 223.66%. The stress was the maximum at 48 h of insecticide treatment (91.58, 35.28, and 189.80%, respectively). In contrast, catalase and superoxide dismutase were reduced in a dose- and time-dependent manner in imidacloprid-fed larvae. The results therefore suggest that imidacloprid impedes mitochondrial function and induces oxidative stress in H. armigera, which contributes to reduced growth of the larvae along with its neurotoxic effect. 相似文献
66.
Synthetic 2′-hydroxy-3,4′,6′-trimethoxy-4-benzyloxychalcone (I) affords (±)-7,3′-di-O-methyleriodictyol (II) and 7,3′-di-O-methylluteolin (or velutin, VII) identical with natural samples. Similarly synthetic 2′-hydroxy-4,4′,6′-trimethoxy-3-benzyloxychalcone (X) gives natural (±)-7,4′-di-O-methyleriodictyol (XI) and 7,4′-di-O-methylluteolin (or pilloin, IX). However, attempts to partially etherify II with one mole of prenyl bromide to obtain the natural prenyl ether failed; only the corresponding diprenyloxychalcone (IV) was obtained. 相似文献
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The present study examines the effects of 30 mg/kg butachlor on the cyanobacterial diversity of rice fields in Eastern Uttar Pradesh and Western Bihar in India. A total of 40 samples were grouped into three classes [(i) acidic, (ii) neutral, and (iii) alkaline soils], based on physicochemical and principle component analyses. Acidic soils mainly harbored Westillopsis, Trichormus, Anabaenopsis, and unicellular cyanobacteria; whereas Nostoc, Anabaena, Calothrix, Tolypothrix, and Aulosira were found in neutral and alkaline soils. Molecular characterization using 16S rRNA PCR and DGGE revealed the presence of 13 different phylotypes of cyanobacteria in these samples. Butachlor treatment of the soil samples led to the disappearance of 5 and the emergence of 2 additional phylotypes. A total of 40 DGGE bands showed significant reproducible changes upon treatment with butachlor. Phylogenetic analyses divided the phylotypes into five major clusters exhibiting interesting links with soil pH. Aulosira, Anabaena, Trichormus, and Anabaenopsis were sensitive to butachlor treatment, whereas uncultured cyanobacteria, a chroococcalean member, Westillopsis, Nostoc, Calothrix, Tolypothrix, Rivularia, Gloeotrichia, Fischerella, Leptolyngbya, and Cylindrospermum, appeared to be tolerant against butachlor at their native soil pH. Butachlor-induced inhibition of nitrogen fixation was found to be 65% (maximum) and 33% (minimum) in the soil samples of pH 9.23 and 5.20, respectively. In conclusion, low butachlor doses may prove beneficial in paddy fields having a neutral to alkaline soil pH. 相似文献
70.
Jaydip Mandal Sitakanta Pattnaik Pradeep K. Chand 《In vitro cellular & developmental biology. Plant》2000,36(4):287-292
Summary Propagation and conservation of four pharmaceutically important herbs, Ocimum americanum L. syn. O. canum Sims. (hoary basil); O basilicum L. (swett basil); O. gratissimum L. (shrubby basil); and O. sanctum L. (sacred basil) was attempted using synthetic seed technology. Synthetic seeds were produced by encapsulating axillary
vegetative buds harvested from garden-grown plants of these four Ocimum species in calcium alginate gel. The gel contained Murashige and Skoog (MS) nutrients and 1.1-4.4 μM benzyladenine (BA). Shoots emerged from the encapsulated buds on all six planting media tested. However, the highest frequency
shoot emergence and maximum number of shoots per bud were recorded on media containing BA. Of the six planting media tested,
both shoot and root emergence from the encapsulated buds in a single step was recorded on growth regulator-free MS medium
as well as on vermi-compost moistened with halfstrength MS medium. Rooted shoots were retrieved from the encapsulated buds
of O. americanum, O. basilicum, and O. sanctum on these two media, whereas shoots of O. gratissimum failed to root. The encapsulated buds could be stored for 60 d at 4°C. Plants retrieved from the encapsulated buds were hardened
off and established in soil. 相似文献