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91.
An increasing number of cancer patients worldwide, especially in third world countries, have raised concern to explore natural drug resources, such as the less explored fresh water filamentous cyanobacteria. Six strains of cyanobacteria (Phormidium sp. CCC727, Geitlerinema sp. CCC728, Arthrospira sp. CCC729, Phormidium sp. CCC731, Phormidium sp. CCC730, and Leptolyngbya sp. CCC732) were isolated (paddy fields and ponds in the Banaras Hindu University, campus) and five strains screened for anticancer potential using human colon adenocarcinoma (HT29) and human kidney adenocarcinoma (A498) cancer cell lines. Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 were the most potent as determined by examination of morphological features and by inhibition of growth by graded concentrations of crude extracts and thin-layer chromatography (TLC) eluates. Cell cycle analysis and multiplex assays using cancer biomarkers also confirmed Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 as cancer drug resources. Apoptotic studies in the cells of A498 (cancer) and MCF-10A (normal human epithelial) exposed to crude extracts and TLC fractions revealed no significant impact on MCF-10A cells emphasizing its importance in the development of anticancer drug. Identification of biomolecules from these extracts are in progress.  相似文献   
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93.
The present study is focused on the extracellular synthesis of silver nanoparticles (AgNPs) using culture supernatant of an agriculturally important bacterium, Serratia sp. BHU-S4 and demonstrates its effective application for the management of spot blotch disease in wheat. The biosynthesis of AgNPs by Serratia sp. BHU-S4 (denoted as bsAgNPs) was monitored by UV–visible spectrum that showed the surface plasmon resonance (SPR) peak at 410 nm, an important characteristic of AgNPs. Furthermore, the structural, morphological, elemental, functional and thermal characterization of bsAgNPs was carried out using the X-ray diffraction (XRD), electron and atomic microscopies, energy dispersive X-ray (EDAX) spectrometer, FTIR spectroscopy and thermogravimetric analyzer (TGA), respectively. The bsAgNPs were spherical in shape with size range of ∼10 to 20 nm. The XRD and EDAX analysis confirmed successful biosynthesis and crystalline nature of AgNPs. The bsAgNPs exhibited strong antifungal activity against Bipolaris sorokiniana, the spot blotch pathogen of wheat. Interestingly, 2, 4 and 10 µg/ml concentrations of bsAgNPs accounted for complete inhibition of conidial germination, whereas in the absence of bsAgNPs, conidial germination was 100%. A detached leaf bioassay revealed prominent conidial germination on wheat leaves infected with B. sorokiniana conidial suspension alone, while the germination of conidia was totally inhibited when the leaves were treated with bsAgNPs. The results were further authenticated under green house conditions, where application of bsAgNPs significantly reduced B. sorokiniana infection in wheat plants. Histochemical staining revealed a significant role of bsAgNPs treatment in inducing lignin deposition in vascular bundles. In summary, our findings represent the efficient application of bsAgNPs in plant disease management, indicating the exciting possibilities of nanofungicide employing agriculturally important bacteria.  相似文献   
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Trial comprising fifty lentil genotypes was conducted at three locations in India during year 2013–2014 for estimation of grain Fe and Zn concentrations and to analyze G × E interactions by employing the additive main effect and multiplication interaction model. The study revealed significant effects for genotype, environment and genotype by environment interaction for both grain Fe and Zn concentration. In this model genotypes with the IPCA score of nearly zero and mean greater than grand mean are considered as adaptable to the studied environments. For grain Fe concentration genotypes P13143, P13135, ILL2581, P2130, LL147, L4603, PL101 and Globe mutant and for grain Zn concentration genotypes P13122, P2239, P3204 and L11-245 were found stable. The diversity analysis using 20 genomic and 54 EST-SSR markers indicated that the studied genotypes were diverse. The EST-SSRs revealed lower polymorphism as compare to genomic SSRs. Two major clusters were identified with 37 % similarity. Indigenous genotypes were grouped in cluster I and all exotic accessions were grouped in cluster II indicating the role of geographic origin in diversity. Based on multi location evaluation for grain Fe and Zn concentrations and molecular characterization crosses are proposed for development of grain Fe and Zn rich varieties (P3220 × L4649 and VL103 × P2130) and development of mapping populations (P13122 × L11-287 and LL931 × P3220) for study of genetics and mapping of QTLs/gene(s).  相似文献   
96.
Costus speciosus is a rich source of commercially important compound Diosgenin, distributed in different regions of India. The present investigation was aimed to quantify diosgenin through High Performance Thin Layer Chromatography in 34 germplasms of Costus speciosus and also to identify the superior sources and to correlate the macronutrients of rhizospheric soil. The starch content varied in microscopic examination and correlated inversely (r=−0.266) with diosgenin content. Findings revealed that the extraction process with acid hydrolysis yielded higher diosgenin content (0.15–1.88 %) as compared to non-hydrolysis (0.009–0.368 %) procedure. Germplasms from Uttar Pradesh (NBCS-4), Jharkhand (NBCS-39) and Bihar (NBCS-2) were identified as elite chemotypes based on hierarchical clustering analysis. The phosphorous content of respective rhizospheric soil correlated positively (r=0.742) with diosgenin content. Findings of present study are useful to identify the new agrotechniques. The elite germplasms can also be used as quality planting material for large scale cultivation in order to assure a sustained supply to the herbal drug industry.  相似文献   
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98.
The present study was designed to appraise the photoprotective, antioxidant, and antibacterial bioactivities of Ruellia tuberosa leaves extracts (RtPE, RtChl, RtEA, RtAc, RtMe, and RtHMe). The results showed that, RtHMe extracts of R. tuberosa was rich in total phenolic content, i. e., 1.60 mgGAE/g dry extract, while highest total flavonoid content was found in RtAc extract, i. e., 0.40 mgQE/g. RtMe showed effective antioxidant activity (%RSA: 58.16) at the concentration of 120 μL. RtMe, RtEA and RtHMe exhibited effective in vitro antibacterial activity against Gram-negative bacteria (E. coli). In silico docking studies revealed that paucifloside (−11.743 kcal/mol), indole-3-carboxaldehyde (−7.519 kcal/mol), nuomioside (−7.275 kcal/mol), isocassifolioside (−6.992 kcal/mol) showed best docking score against PDB ID 2EX8 [penicillin binding protein 4 (dacB) from Escherichia coli, complexed with penicillin-G], PDB ID 6CQA (E. coli dihydrofolate reductase protein complexed with inhibitor AMPQD), PDB ID 2Y2I [Penicillin-binding protein 1B in complex with an alkyl boronate (ZA3)] and PDB ID 2OLV (from S. aureus), respectively. Docked phytochemicals also showed good drug likeness properties.  相似文献   
99.

Background

Enteroaggregative Escherichia coli (EAEC) is one of the most common bacterial pathogens associated with the etiology of persistent diarrhea. A characteristic feature of EAEC-pathogenesis is the induction of profound inflammatory response in the intestinal epithelium. The present study was designed to investigate the underlying mechanism of inflammatory responses induced by a novel galactose specific adhesin of T7 strain of EAEC (EAEC-T7) in human intestinal epithelial cell line (INT-407).

Methods

INT-407 cells were stimulated with the adhesin in the absence and presence of anti-adhesin (IgGAD)/d-galactose/H7/staurosporin (inhibitor of PKC)/PD098059 (inhibitor of MEK)/SB203580 (inhibitor of p38-MAPkinase)/AG490 (inhibitor of JAK (-2,-3)/STAT-3 pathway). The expression of activated Raf-1, MEK-1, ERK1/2, JNK, p38-MAPK and STAT-3 was analyzed by Western immunoblot. Release of interleukin-8 (IL-8) was measured by ELISA.

Results

The adhesin was found to induce activation of Raf-1, MEK-1, ERK1/2, p38-MAPK and STAT-3, which was reduced in the presence of IgGAD/d-galactose. The activation of Raf-1 was found to be attenuated in the presence of H7/staurosporin. The expression of phosphorylated STAT-3 was downregulated in the presence of AG490 and PD098059. Further, the adhesin induced IL-8 secretion was reduced in the presence of the inhibitors of MEK (PD098059), p38-MAPK (SB203580) and JAK (-2,-3)/STAT-3 pathway (AG490).

Conclusions

We propose that STAT-3 activation is quintessential for the galactose specific adhesin induced IL-8 secretion by INT-407 cells and must occur in concert with the activation of ERK1/2.

General significance

Our contribution regarding the galactose specific adhesin mediated signaling leads to an improved understanding of the EAEC-pathogenesis and may provide novel therapeutic approaches to combat EAEC infection.  相似文献   
100.
Foliar spraying of Brassica carinata (cv. PC 5) with paclobutrazol (PP 333) at 5, 10 and 20 g ml-1 concentrations, reduced plant height significantly and modified the canopy structure by enhancing the number of branches (primary, secondary and tertiary) and the angle of insertion of primary branches on the main axis. The seed yield per plant also increased mainly due to increase in the number of siliquae per plant. Paclobutrazol increased total dry matter of plants and partitioning coefficients. The leaves in paclobutrazol-treated plants exhibited higher chlorophyll content, and they remained intact on plants for longer than the controls. The seeds from paclobutrazol-treated plants had higher levels of proteins, strarch and total soluble sugars but less total seed oil content.  相似文献   
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