Production,HPLC analysis,and in situ apoptotic activities of swainsonine toward lepidopteran,Sf‐21 cell line

Swainsonine, a secondary metabolite from Metarhizium anisopliae has been extensively studied in the complementary areas of therapeutics and toxicology. This work aims to develop a simple UV‐HPLC method of analyses for swainsonine in Metarhizium fermentation broth and to explore its in situ entomotoxic activities. The partially purified broth was quantitatively analyzed using middle UV (205 nm)‐reverse phase HPLC method with different mobile phases and gradient programmes. Swainsonine was eluted as single peak at (t_e) 6.0–6.9 min with average concentration of 4.04 ± 0.52 μg/mL using optimal mobile phase (0.1% trifluoroacetic acid in water and acetonitrile). The mass spectrometry analysis further indicated the characteristic MS1 species for swainsonine, [M+H]⁺ 174.30 in corresponding HPLC peaks. The antiproliferative effects of swainsonine on lepidopteran, Sf‐21 cells were determined through 3‐(4, 5‐dimethylthia‐zol‐2‐yl)?2, 5‐diphenyl tetrazolium bromide (IC_{50 standard} = 3.90 μM and IC_{50 purified} = 5.27 μM) and trypan blue dye exclusion (IC_{50 standard} = 6.91 μM and IC_{50 purified} = 8.67 μM) assays. The fluorescence activated cell sorting evaluation of Sf‐21 cells showed nearly 35% and 42% of population in various apoptotic stages at 36 h, when treated with standard and purified swainsonine, respectively. The morphodimensional field emission scanning electron and atomic force microscopic analyses further confirmed the characteristic apoptotic features like membrane blebbings, ruptures and volume shrinkage in the lepidopteran cells after 24–36 h of post‐treatment incubation. The study describes the potential entomotoxic activities of swainsonine and its role in the virulence of Metarhizium spp. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1196–1205, 2014     

Enhanced ethanol production from sugarcane juice by galactose adaptation of a newly isolated thermotolerant strain of Pichia kudriavzevii

The thermotolerant yeast strain isolated from sugarcane juice through enrichment technique was identified as a strain of Pichiakudriavzevii (Issatchenkiaorientalis) through molecular characterization. The P. kudriavzevii cells adapted to galactose medium produced about 30% more ethanol from sugarcane juice than the non-adapted cells. The recycled cells could be used for four successive cycles without a significant drop in ethanol production. Fermentation in a laboratory fermenter with galactose adapted P. kudriavzevii cells at 40 °C resulted in an ethanol concentration and productivity of 71.9 g L⁻¹ and 4.0 g L⁻¹ h⁻¹, respectively from sugarcane juice composed of about 14% (w/v) sucrose, 2% (w/v) glucose and 1% (w/v) fructose. In addition to ethanol, 3.30 g L⁻¹ arabitol and 4.19 g L⁻¹ glycerol were also produced, whereas sorbitol and xylitol were not formed during fermentation. Use of galactose adapted P. kudriavzevii cells for ethanol production from sugarcane juice holds potential for scale-up studies.     

Quantification of the relative importance of CTL, B cell, NK cell, and target cell limitation in the control of primary SIV-infection

CD8+ cytotoxic T lymphocytes (CTLs), natural killer (NK) cells, B cells and target cell limitation have all been suggested to play a role in the control of SIV and HIV-1 infection. However, previous research typically studied each population in isolation leaving the magnitude, relative importance and in vivo relevance of each effect unclear. Here we quantify the relative importance of CTLs, NK cells, B cells and target cell limitation in controlling acute SIV infection in rhesus macaques. Using three different methods, we find that the availability of target cells and CD8+ T cells are important predictors of viral load dynamics. If CTL are assumed to mediate this anti-viral effect via a lytic mechanism then we estimate that CTL killing is responsible for approximately 40% of productively infected cell death, the remaining cell death being attributable to intrinsic, immune (CD8+ T cell, NK cell, B cell) -independent mechanisms. Furthermore, we find that NK cells have little impact on the death rate of infected CD4+ cells and that their net impact is to increase viral load. We hypothesize that NK cells play a detrimental role in SIV infection, possibly by increasing T cell activation.     

Role of enzymes of sucrose-starch conversion in seed sink strength in mung bean

Changes in the activities of sucrose synthase (SuSy), ADP-glucose pyrophosphorylase (AGPase), UDP-glucose pyrophosphorylase (UGPase), alkaline inorganic pyrophosphatase, 3-phosphoglycerate (3-PGA) phosphatase and amylases were monitored in relation to accumulation of starch in developing pods of mung bean (Vigna radiata L.). With the advancement in the seed development, the contents of starch rose with a concomitant fall in the branch of inflorescence and podwall after 10 d after flowering. The activity of UDPase in all the three pod tissues remained higher than the activity of AGPase showing it to be an important enzyme controlling carbon flux. The activity of alkaline inorganic pyrophosphatase in developing seed in contrast to 3-PGA phosphatase correlated with starch accumulation rate. Activity of β-amylase increased in all the pod tissues till maturity. It appears that the cooperative action of SuSy, UGPase and AGPase controls the efficient partitioning of sucrose into ADP glucose and thereby regulate the seed sink strength of the mung bean.     

Design, synthesis and antimycobacterial evaluation of novel 3-substituted-N-aryl-6,7-dimethoxy-3a,4-dihydro-3H-indeno[1,2-c]pyrazole-2-carboxamide analogues

In the present investigation, a series of 3-substituted-N-aryl-6,7-dimethoxy-3a,4-dihydro-3H-indeno[1,2-c]pyrazole-2-carboxamide analogues were synthesized and were evaluated for antitubercular activity by two fold serial dilution technique. All the newly synthesized compounds showed moderate to high inhibitory activities against Mycobacterium tuberculosis H₃₇Rv and INH resistant M. tuberculosis. The compound N,3-bis(4-fluorophenyl)-6,7-dimethoxy-3a,4-dihydro-3H-indeno[1,2-c]pyrazole-2-carboxamide (4c) was found to be the most promising compound active against M. tuberculosis H₃₇Rv and isoniazid resistant M. tuberculosis with minimum inhibitory concentration 0.78 μM.     

Design and implementation of transaction privacy by virtue of ownership and traceability in blockchain based supply chain

Cluster Computing - Blockchain was at the top of the 2016 Gartner hype cycle and has been integrated into business profiles by numerous start-ups. Since the emergence of blockchain through Bitcoin,...     

New vision on the new era of genome study

Functional & Integrative Genomics -     

Intense green light emission and thermoluminescence glow curve analysis of Tb3+-activated CaY2O4 phosphor

Here, the synthesis and luminescence analysis of the Tb³⁺-activated phosphor were reported. The CaY₂O₄ phosphors were synthesized using a modified solid-state reaction method with a variable doping concentration of Tb³⁺ ion (0.1–2.5 mol%). As synthesized, the phosphor was characterized using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis techniques for the optimized concentration of doping ions. The prepared phosphor showed a cubic structure, and FTIR analysis confirmed functional group analysis. It was discovered that the intensity of 1.5 mol% was higher than at other concentrations after the photoluminescence (PL) excitation and emission spectra were recorded for different concentrations of doping ions. The excitation was monitored at 542 nm, and the emission was monitored at 237 nm. At 237 nm excitation, the emission peaks were found at 620 nm (⁵D₄→⁷F₃), 582 nm (⁵D₄→⁷F₄), 542 nm (⁵D₄→⁷F₅), and 484 nm (⁵D₄→⁷F₆). The 1931 CIE (x, y) chromaticity coordinates showed the distribution of the spectral region calculated from the PL emission spectra. The values of (x = 0.34 and y = 0.60) were very close to dark green emission. Therefore, the produced phosphor would be very useful for light-emitting diode (green component) applications. Thermoluminescence glow curve analysis for various concentrations of doping ions and various ultraviolet (UV) exposure times was carried out, and a single broad peak was found at 252°C. The computerized glow curve deconvolution method was used to obtain the related kinetic parameters. The prepared phosphor exhibited an excellent response to UV dose and could be useful for UV ray dosimetry.     

Charged nylon membrane substrate for convenient and versatile high resolution microscopic analysis of Escherichia coli & mammalian cells in suspension culture

Preparation of isolated cells and microorganisms for ultrastructural examination always provides a challenge in terms of adequate immobilization of the cells and prevention of subsequent sample loss and damage during various steps of sample processing. Using a positively charged nylon membrane substrate we demonstrate that it is possible to easily immobilize and retain a sample of isolated cells in culture for a wide variety of microscopy-based techniques. Radiolabelled E. coli cells when immobilized on the charged membrane were seen to be highly resistant to detachment when subjected to the normal sample processing procedures associated with microscopy. In contrast cells on regular millipore membranes were rapidly lost during sample preparation. We demonstrate the utility of charged nylon membranes for a wide variety of microscopy based analysis including scanning and transmission electron microscopy (SEM and TEM), atomic force microscopy (AFM), TEM based immunogold labelling, laser confocal microscopy and SEM based elemental analysis.