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81.
Chenopods are generally regarded as non-host plants for mycorrhizal fungi and are believed not to benefit from colonization by mycorrhizal fungi. Perennial Atriplex nummularia Lindl., growing under field conditions, showed a relatively high level of colonization by mycorrhizal fungi (10–30% of root length colonized) in spring and summer. Accordingly, two glasshouse experiments were designed to assess the effects of inoculation with mycorrhizal fungi (with a single species or a mixture of different species) on growth, nutrient uptake, and rhizosphere bacterial community composition of A. nummularia at high and low salinity levels (2.2 and 12 dSm–1). Only low and patchy colonization by mycorrhizal fungi (1–2 of root length colonized) was detected in inoculated plants under glasshouse conditions which was unaffected by salinity. Despite the low colonization, inoculation increased plant growth and affected nutrient uptake at both salinity levels. The effects were higher at an early stage of plant development (6weeks) than at a later stage (9–10 weeks). Salinity affected the bacterial community composition in the rhizosphere as examined by ribosomal intergenic spacer amplification (RISA) of 16S rDNA, digitization of the band patterns and multivariate analysis. The effects of inoculation with mycorrhizal fungi on growth of A. nummularia may be attributed to (i) direct effects of mycorrhizal fungi on plant nutrient uptake and/or (ii) indirect effects via mycorrhizal-induced changes in the bacterial community composition.  相似文献   
82.
An efficient diastereoselective synthesis of spirocyclopropaneoxindoles is reported using three‐component reactions of various phenacylidenetriphenylphosphorane, isatins and phenacyl bromide under ultrasonic irradiation. The structures of synthesized spirocyclopropaneoxindoles were characterized by their spectral data. The antioxidant activities of the synthesized compounds were evaluated by 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging assay. Among the products, those with NH group in their structure exhibited higher antioxidant activities than other derivatives. Also, in vitro cytotoxicity of compounds 4b , 4e , 4j , 4k were examined against heLa cancer cell lines using MTT assay. The results revealed that compound 4j with chlorine substituent on phenyl group displayed higher cytotoxicity activity (IC50=4.50±0.30 μg/mL) after 48 h.  相似文献   
83.
A series of novel thiazolo[3,2‐a]pyrimidines were synthesized and characterized by FT‐IR, 1H, 13C‐NMR and mass techniques. Their antioxidant activities were investigated by 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging assay and the results showed that all the synthesized compounds exhibit good antioxidant activity. In addition, it was found that any substituent on the aromatic ring of the products plays an important role in their antioxidant activity. In vitro cytotoxicity of compounds 4a – 4j was investigated using MTT cell viability assay. Among these compounds, 6‐ethyl 2,3‐dimethyl 5‐(4‐chlorophenyl)‐7‐methyl‐2,3‐dihydro‐5H‐[1,3]thiazolo[3,2‐a]pyrimidine‐2,3,6‐tricarboxylate ( 4e ) bearing a chlorine substituent displayed the highest cytotoxic effect (IC50=6.26±0.6 μm ) in comparison with doxorubicin (IC50=0.68±0.1 μm ) as a standard after 72 h. Therefore, it is assumed that these compounds could be used as effective antioxidant and cytotoxic agents.  相似文献   
84.
The aerial parts of Salvia multicaulis, S. sclarea and S. verticillata were collected at full flowering stage. The essential oils were isolated by hydrodistillation and analyzed by combination of capillary GC and GC-MS. The in vitro antimicrobial activity of the essential oils were studied against eight Gram-positive and Gram-negative bacteria (Bacillus subtilis, Bacillus pumulis, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae) and three fungi (Candida albicans, Saccharomyces cerevisiae and Aspergillus niger). The results of antibacterial activity tests of the essential oils according to the disc diffusion method and MIC values indicated that all the samples have moderate to high inhibitory activity against the tested bacteria except for P. aeruginosa which was totally resistant. In contrast to antibacterial activity, the oils exhibited no or slight antifungal property, in which only the oil of S. multicaulis showed weak activity against two tested yeasts, C. albicans and S. cerevisiae.  相似文献   
85.
International Journal of Peptide Research and Therapeutics - Antimicrobial peptides (AMPs) mainly introduced as a new generation of antibiotics, could be used for broad medical and biotechnological...  相似文献   
86.
Licorice (Glycyrrhiza glabra L. var. glabra, Fabaceae) is considered as a model plant synthesizing triterpenoid secondary compounds. It is known that glycyrrhizin is accumulated in thickened intact licorice roots. The effects of methyl jasmonate (MeJa) and salicylic acid (SA) on plant growth and production of glycyrrhizin in the roots of in vitro cultured 65-day-old plants were studied. Increasing amounts of glycyrrhizin in the roots treated with MeJa inhibited root growth, while SA increased the amount of glycyrrhizin without negative effects on growth. Treatment of plantlets with 0.1–2 mM MeJa and 0.1 and 1 mM SA enhanced the production of glycyrrhizin by 3.8 and 4.1 times, respectively, as compared to the controls. Results support the hypothesis that production of glycyrrhizin is related to a defense response system of the licorice.  相似文献   
87.
This study examined the influence of three inoculant strains of Bradyrhizobium japonicum (Thal-8, Tal 620, Dulawala) on the ability of chickpea (Cicer arietinum (L.) to adapt to drought-stress. Strain Thal-8 was most effective in the root-nodule symbiosis and also partially alleviated decreased growth and yield imposed by drought stress. Strain Thal-8, in pure culture, also produced higher amounts of gibberellic acid (GA) and indole-3-acetic acid (IAA) and lower amounts of abscisic acid (ABA) than the other two test strains. Thal-8 increased the root biomass, GA and IAA contents of leaves of chickpea plants, including ICC 4948NN, a non-nodulating line. These results are consistent with the hypothesis that GA and IAA is produced by the Thal-8 strain and/or elevates levels of these phytohormones in chickpeas. This contributes to its high performance as a nitrogen-fixing microsymbiont. The growth-promoting response evoked by different strains of Bradyrhizobium correlated with higher ratios of GA and IAA relative to ABA phytohormones in the plants.  相似文献   
88.
Corrosion and scaling is one of the most important factors influencing drinking water quality that cause health disorders and economic problems. The aim of this study was to evaluate these phenomena in two sources of surface (Makou city) and ground water (Khoy city) in water networks. Corrosion and scaling potential was surveyed by Langelier, Ryzener, aggressiveness, Larson and Puckorius Indices and with measuring water physical, chemical, and microbial parameters. Statistical paired samples t-test displayed significant difference in means value of Langelier, Ryzener, Puckorius indices between cold and warm seasons of the year in Khoy samples and significant difference in means value of Ryzener, Puckorius and aggressiveness indices between cold and warm seasons of the year in Makou samples (p-value <0.001). Heterotrophic plate count water samples investigated in two cold and hot seasons in Khoy were respectively 14 ± 16 cfu ml?1 and 41 ± 26 cfu ml?1 and in the town of Makou were 11 ± 7 cfu ml?1 and 61 ± 29 cfu ml?1, respectively. In terms of health impacts, corrosion in different mains is important, then providing proper measures for balancing water quality before entering to the network and substituting of mains to prevent economic and health problems are necessary.  相似文献   
89.
Despite several studies on fish hormone therapy, finding new candidates may provide more reproductive efficiency in artificial propagation. Kisspeptins, being upstream of the hypothalamic–pituitary-gonadal axis, appear to play a key role in the reproduction process. In the present study, the effect of different variants of kisspeptide, including goldfish (Carassius auratus) kiss1 kisspeptin (Kiss1), human kisspeptin (Hkiss), and their combination (Kiss1 + H), on the reproductive indices of goldfish broodstock in comparison to Ovaprim (a typical synthetic Gnrh hormone) was investigated. Peptides (Kiss1 and Hkiss) were synthesized using a solid-phase synthesis approach. Kiss1 and Hkiss were injected at a dose of 100 μg kg−1 body weight, blood samples were taken 6 h after injection and sex hormones (E2, Dhp, and 11-Kt), gonadotropins (Lh and Fsh), cortisol and reproductive indices (fecundity, fertilization and hatching percentage) were measured. The results showed a significant increase of plasma sex hormones and gonadotropins in fish treated with kisspeptins. In addition, the cortisol and lipoprotein lipase in Kiss1, Hkiss and Kiss1 + H were remarkably increased compared to Ovaprim. In conclusion, kisspeptins could be a more suitable candidate than Ovaprim for accelerating and synchronizing oocyte maturation in the fisheries industry.  相似文献   
90.
Hemicellulose hydrolysates of the agricultural residues bagasse, corn stover, and corn hulls plus fibers were readily fermented to ethanol by recombinantEscherichia coli strain KO11. Corn steep liquor and crude yeast autolysate served as excellent nutrients. Fermentations were substantially complete within 48 h, often achieving over 40 g ethanol L–1. Ethanol yields ranged from 86% to over 100% of the maximum theoretical yield (0.51 g ethanol g sugar–1.  相似文献   
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