Two-step separation of nostotrebin 6 from cultivated soil cyanobacterium (Nostoc sp.) by high performance countercurrent chromatography

High performance countercurrent chromatography (HPCCC) was successfully applied for the separation of nostotrebin 6 from cultivated soil cyanobacteria in a two-step operation. A two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (4:5:4:5, v/v/v/v) was employed for the HPCCC separation. In the first-step operation, its neutral upper phase was used as stationary phase and its basic lower phase (1% NH3 in lower phase) was employed as mobile phase at a flow rate of 1 mL/min. In the second operation step, its neutral upper phase was used as stationary phase, whereas both its neutral lower phase and basic lower phase were employed as mobile phase with a linear gradient elution at a flow rate of 0.8 mL/min. The revolution speed and temperature of the separation column were 1,000 rpm and 30 °C, respectively. Using HPCCC followed by clean-up on Sephadex LH-20 gel, 4 mg of nostotrebin 6 with a purity of 99% as determined by HPLC/DAD-ESI-HRMS was obtained from 100 mg of crude extract. The chemical identity of the isolated compound was confirmed by comparing its spectroscopic data (UV, ESI-HRMS, ESI-HRMS2) with those of an authentic standard and data available in the literature.This work was supported by the project ALGAIN (reg. nr. CZ.1.07/2.3.00/30.0059) and the Center for Algal Biotechnology Třeboň-ALGATECH (CZ. 1.05/21.00/03.0110)

Action research for transformative change

As major policy actors (e.g. governments, global organisations) grapple with 'wicked’ sustainability challenges, the use of demonstration projects or ‘living labs’ has promise in showcasing potential solutions. However, these projects can struggleto realise enduring change, with initial experimental deliverables tending not to be replicated and remaining as once-offs. As well as demonstrating solutions, projects also need to overcome the considerable inertia in the complex systems of organisations and institutions that govern (or indeed generate) sustainability problems. Here we argue that demonstration projects, while initially impactful, could be more likely to realise transformative change if they were designed more thoroughly as action research projects, working with partners to not only deliver and measure demonstrations of solutions, but also demonstrate changes to organisations and institutions to remove barriers and facilitate replication. We note the important role ofboth engaged leadership and explicitly-stated theories of change in maximising the potential of projects designed in this way

Desulfurization of Dibenzothiophene by Pseudomonas fluorescens (UCP 1514) Leading to the Production of Biphenyl

Dibenzothiophene (DBT) is a typical recalcitrant thiophenic sulfur component of fuels, and its desulphurization has been a model reaction in the treatment of these compounds. Based on this information, the potential of Pseudomonas fluorescens (UCP 1514) on the desulfurization of dibenzothiphene was studied, in order to use it for reducing the sulfur content of diesel oil in compliance with environmental regulations. The result of biodegradation by the bacteria was determined by undertaking high-performance liquid chromatography of the metabolites produced. These can also be identified by gas chromatography with a mass spectrometry detector, and doing so revealed a sulfur-free product, biphenyl, as the final product of the degradation process. The results showed a decrease of 73% in dibenzothiophene content, which means that P. fluorescens removes sulfur from dibenzothiophene with a good selectivity to form biphenyl. These promising results indicate that P. fluorescens has an interesting potential to degrade sulfur-containing compounds in diesel oil and thereby could help in removing sulfur content from diesel oil. The process of microbial desulfurization described herein can be used particularly after carrying out hydrodesulfurization. Consequently, the sulfur content could be reduced even further. Applying P. fluorescens UCP 1514 in dibenzothiophene could help to understand the nature of the biodegradation process and to achieve the regulatory standards for sulfur level in fossil fuels

Optimization and evaluation of biosurfactant produced by Pantoea sp. using pineapple peel residue, vegetable fat and corn steep liquor

In this study, the authors have investigated the potential of a bacterial strain of Pantoea sp., isolated from wastewater of the textile industry, for the production of biosurfactant. The biosurfactant production was optimized by the combination of CCD (central composite design) and RSM (response surface methodology). To assess the effects and interactions of medium the vegetable fat (1.5, 2.0 and 2.5 v/v), the variables corn steep liquor (2.0, 5.0 and 8.0 v/v) and pineapple peel residue (10.0, 25.0 and 40.0 v/v) on the surface tension were evaluated. The empirical model developed through RSM in terms of the effective operational factors mentioned above was found to be adequate to describe the biosurfactant production. Compositional analysis of the produced biosurfactant has been carried out by FT-IR (Fourier transform infrared spectoscopy) and subjected to the test of removing hydrocarbons. Through the analysis, vegetable fat and pineapple peel residue were found to be the most significant factors, whereas corn steep liquor had less effect within the ranges investigated. A maximum reduction in surface tension of 30.00 mN/m was obtained under the optimal conditions of 2.0% (v/v) vegetable fat concentration, 5.0% (v/v) corn steep liquor and 25.0% (v/v) pineapple peel residue concentration of medium. FT-IR spectrometer analysis of the biosurfactant characterized it as a glycolipid derivative. The biosurfactant exhibited the ability to solubilize the hydrocarbons tested, working between 64% and 92%. According to consists of bars with a length proportional to the absolute value of the estimated effects divided by the standard error. On this chart, ANOVA (analysis of variance) effect estimates are arranged from the largest to smallest absolute value. The chart includes a vertical line at the critical p-value of 0.05. Effects for which the bars are smaller than the critical p-value are considered non-significant and do not have an effect on the response variables. The effects are either positive or negative ANOVA; the determination of regression coefficients and the construction of graphs were performed using the Statistical® program, version 7.0 (Statsoft Inc, RSA). The results, the biosurfactant produced by Pantoea sp. can be a valuable source for application in rapid environmental bioremediation9269279CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À CIÊNCIA E TECNOLOGIA DO ESTADO DE PERNAMBUCO - FACEPEsem informaçã

Counter-current chromatography for the separation of terpenoids: A comprehensive review with respect to the solvent systems employed

Copyright @ 2014 The Authors.This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Natural products extracts are commonly highly complex mixtures of active compounds and consequently their purification becomes a particularly challenging task. The development of a purification protocol to extract a single active component from the many hundreds that are often present in the mixture is something that can take months or even years to achieve, thus it is important for the natural product chemist to have, at their disposal, a broad range of diverse purification techniques. Counter-current chromatography (CCC) is one such separation technique utilising two immiscible phases, one as the stationary phase (retained in a spinning coil by centrifugal forces) and the second as the mobile phase. The method benefits from a number of advantages when compared with the more traditional liquid-solid separation methods, such as no irreversible adsorption, total recovery of the injected sample, minimal tailing of peaks, low risk of sample denaturation, the ability to accept particulates, and a low solvent consumption. The selection of an appropriate two-phase solvent system is critical to the running of CCC since this is both the mobile and the stationary phase of the system. However, this is also by far the most time consuming aspect of the technique and the one that most inhibits its general take-up. In recent years, numerous natural product purifications have been published using CCC from almost every country across the globe. Many of these papers are devoted to terpenoids-one of the most diverse groups. Naturally occurring terpenoids provide opportunities to discover new drugs but many of them are available at very low levels in nature and a huge number of them still remain unexplored. The collective knowledge on performing successful CCC separations of terpenoids has been gathered and reviewed by the authors, in order to create a comprehensive document that will be of great assistance in performing future purifications. © 2014 The Author(s)

Tuba, a Cdc42 GEF, is required for polarized spindle orientation during epithelial cyst formation

An RNAi screen picks Tuba out of the GTPase exchange factor (GEF) orchestra as a regulator of cell polarity in epithelial morphogenesis. (See also a companion paper from Rodriguez-Fraticelli et al., in this issue.

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

John Clare and place

This chapter tackles issues of place in the self-presentation and critical reception of John Clare, and pursues it across a number of axes. The argument centres on the placing of Clare both socio-economically and ‘naturally’, and limitations exerted upon perceptions of his work. Interrogating criticism this chapter finds a pervasive awkwardness especially in relation to issues of class and labour. It assesses the contemporary ‘placing’ of Clare, and seemingly unavoidable insensitivities to labour and poverty in the history industry, place-naming, and polemical ecocriticism. It assesses the ways Clare represents place – in poverty, in buildings, in nature – and, drawing on Michel de Certeau, considers the tactics Clare uses to negotiate his place. It pursues trajectories to ‘un-place’ Clare: the flight of fame in Clare’s response to Byron; and the flight of an early poem in songbooks and beyond, across the nineteenth century