Processing chain

  • 文章类型: Journal Article
    Mechanisms of carrion insect succession have been interpreted separately from interspecific interactions between early and later colonists or from changes in volatile organic compounds perceived by insects resulting from the progression of decomposition. To link these perspectives, we examined through laboratory and field experiments whether the modification of volatile organic compounds by early colonists could be a mechanism of succession. In the laboratory experiment, we used Necrophila japonica (Coleoptera, Staphylinidae) as an early colonist and examined its effects on the emissions of important volatile attractants for carrion insects, dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) from carcasses. We collected DMDS and DMTS, using the static headspace method, under the following conditions: (i) rat carcass, (ii) rat carcass with artificial damage to the abdomen, (iii) rat carcass fed on by 10 Ne. japonica individuals, and (iv) 10 Ne. japonica individuals, and analyzed the collected gases using a gas chromatograph-mass spectrometer. After 12 and 30 h, carcasses fed on by Ne. japonica emitted higher concentrations of DMDS and DMTS than in other conditions. In the field experiment, we examined the effects of DMDS and DMTS on the attraction of carrion insects using traps baited with a mixture of DMDS and DMTS, hexane (odors unrelated to carcasses), or an empty microtube. Traps baited with DMDS and DMTS attracted more necrophagous species and individuals than traps not baited with this combination. These results showed that accelerated emissions of DMDS and DMTS from carcasses caused by early colonists may contribute to community assembly during carrion insect succession.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    广泛的应用范围,从临床诊断到各种行业的生物传感器,使乳酸脱氢酶(LDH)对重组蛋白生产非常有趣。重组LDH的表达目前主要在不受控制的摇瓶培养中进行,导致蛋白质主要以其可溶形式产生。然而,收益率相当低。由于诸如增加的时空产率和目标产物的高纯度的若干益处,包涵体(IB)方法已经引起了很多关注。因此,为了调查这种处理策略对ldhL1生产的适用性,开发了一种指导IBs生产而不是可溶性产物形成的分批补料发酵。结果表明,通过将qs增加到0.25gg-1h-1,相当于qs的21%,发酵的时空产量可以增加近3倍,max,诱导后将温度保持在37°C。开发了增溶和重折叠单元操作以恢复ldhL1的全部生物活性。筛选溶解和重折叠条件的系统方法揭示了缓冲液组成和处理策略,最终在重折叠步骤中产生50%的产物回收率。揭示了下游加工链中的主要优化潜力。回收的ldhL1在pH5.5和30°C下表现出最佳活性,具有高催化活性,丙酮酸和NADH的KM值为0.46mM和0.18mM,分别。这些特点,表明这里生产的LDH是各种商业应用的有价值的来源,特别是考虑低pH环境。
    A broad application spectrum ranging from clinical diagnostics to biosensors in a variety of sectors, makes the enzyme Lactate dehydrogenase (LDH) highly interesting for recombinant protein production. Expression of recombinant LDH is currently mainly carried out in uncontrolled shake-flask cultivations leading to protein that is mostly produced in its soluble form, however in rather low yields. Inclusion body (IB) processes have gathered a lot of attention due to several benefits like increased space-time yields and high purity of the target product. Thus, to investigate the suitability of this processing strategy for ldhL1 production, a fed-batch fermentation steering the production of IBs rather than soluble product formation was developed. It was shown that the space-time-yield of the fermentation could be increased almost 3-fold by increasing qs to 0.25 g g-1 h-1 which corresponds to 21% of qs,max, and keeping the temperature at 37°C after induction. Solubilization and refolding unit operations were developed to regain full bioactivity of the ldhL1. The systematic approach in screening for solubilization and refolding conditions revealed buffer compositions and processing strategies that ultimately resulted in 50% product recovery in the refolding step, revealing major optimization potential in the downstream processing chain. The recovered ldhL1 showed an optimal activity at pH 5.5 and 30∘C with a high catalytic activity and KM values of 0.46 mM and 0.18 mM for pyruvate and NADH, respectively. These features, show that the here produced LDH is a valuable source for various commercial applications, especially considering low pH-environments.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    Mycotoxins are frequently found in fruits and fruit juices. However, data about occurrence and fate of mycotoxins along the fruit juice processing chain are currently insufficient. Herein, a liquid chromatographic/tandem mass spectrometric (LC-MS/MS) multi-mycotoxin method was developed and applied to investigate the effect of technological unit operations on the fate of three of the most relevant mycotoxins along the processing chain for cloudy and clear apple juice, namely patulin (PAT), ochratoxin A (OTA), and alternariol (AOH). Raw juice obtained directly after dejuicing was spiked with the aforementioned mycotoxins at pilot-plant scale prior to subjecting it to different technological unit operations. Regarding clear apple juice production treatment with a pectinolytic enzyme preparation, and pasteurization were insignificant for mycotoxin reduction, but fining with subsequent filtration was effective, although the mycotoxins showed different affinity towards the tested agents. The most effective fining agent was activated charcoal/bentonite in combination with ultrafiltration, which removed OTA (54 µg/L) and AOH (79 µg/L) to not quantifiable amounts (limit of quantification (LOQ) 1.4 and 4.6 µg/L, respectively), while PAT was reduced only by 20% (from 396 to 318 µg/L). Regarding cloudy apple juice production, all studied processing steps such as centrifugation and pasteurization were ineffective in reducing mycotoxin levels. In brief, none of the common steps of clear and cloudy apple juice production represented a fully effective safety step for minimizing or even eliminating common mycotoxins. Thus, ensuring the sole use of sound apples should be of utmost importance for processors, particularly for those manufacturing cloudy juices.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    无标记蛋白质组定量(LFQ)是由定量工具和随后的数据处理方法共同定义的多步骤工作流程,已广泛应用于当前的生物医学领域。农业,和环境研究。尽管最近取得了进展,深入和高质量的量化仍然极具挑战性,需要通过比较评估LFQ的性能来优化LFQ。然而,使用不同标准(精度,准确度,和鲁棒性)差异很大,大量潜在的LFQ成为全面优化蛋白质组定量的瓶颈之一。在这项研究中,一种新颖的策略,能够从数千个工作流程中发现同时增强性能的LFQ(集成18个量化工具和3,128个操作链),因此被提议。首先,实现精度同步提高的可行性,准确度,通过共同优化LFQ的多步操作链,系统地评估了LFQ的稳健性。第二,基于通过不同采集模式的各种量化测量获得的各种基准数据集,这种新颖的策略成功地确定了许多操作链,这些操作链同时提高了跨多个标准的性能。最后,为了进一步增强蛋白质组定量并发现最佳性能的LFQ,开发了一个在线工具(https://idrblab.org/anpela/),可以对整个LFQ工作流程进行集体绩效评估(从多个角度)。这项研究证实了实现精度同步提高的可行性,准确度,和鲁棒性。本研究中提出和验证的新策略以及在线工具可能会为需要基于质谱的LFQ技术的研究领域提供有用的指导。
    The label-free proteome quantification (LFQ) is multistep workflow collectively defined by quantification tools and subsequent data manipulation methods that has been extensively applied in current biomedical, agricultural, and environmental studies. Despite recent advances, in-depth and high-quality quantification remains extremely challenging and requires the optimization of LFQs by comparatively evaluating their performance. However, the evaluation results using different criteria (precision, accuracy, and robustness) vary greatly, and the huge number of potential LFQs becomes one of the bottlenecks in comprehensively optimizing proteome quantification. In this study, a novel strategy, enabling the discovery of the LFQs of simultaneously enhanced performance from thousands of workflows (integrating 18 quantification tools with 3,128 manipulation chains), was therefore proposed. First, the feasibility of achieving simultaneous improvement in the precision, accuracy, and robustness of LFQ was systematically assessed by collectively optimizing its multistep manipulation chains. Second, based on a variety of benchmark datasets acquired by various quantification measurements of different modes of acquisition, this novel strategy successfully identified a number of manipulation chains that simultaneously improved the performance across multiple criteria. Finally, to further enhance proteome quantification and discover the LFQs of optimal performance, an online tool (https://idrblab.org/anpela/) enabling collective performance assessment (from multiple perspectives) of the entire LFQ workflow was developed. This study confirmed the feasibility of achieving simultaneous improvement in precision, accuracy, and robustness. The novel strategy proposed and validated in this study together with the online tool might provide useful guidance for the research field requiring the mass-spectrometry-based LFQ technique.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

       PDF(Pubmed)

  • 文章类型: Journal Article
    Proximal sensing as the near field counterpart of remote sensing offers a broad variety of applications. Imaging spectroscopy in general and translational laboratory imaging spectroscopy in particular can be utilized for a variety of different research topics. Geoscientific applications require a precise pre-processing of hyperspectral data cubes to retrieve at-surface reflectance in order to conduct spectral feature-based comparison of unknown sample spectra to known library spectra. A new pre-processing chain called GeoMAP-Trans for at-surface reflectance retrieval is proposed here as an analogue to other algorithms published by the team of authors. It consists of a radiometric, a geometric and a spectral module. Each module consists of several processing steps that are described in detail. The processing chain was adapted to the broadly used HySPEX VNIR/SWIR imaging spectrometer system and tested using geological mineral samples. The performance was subjectively and objectively evaluated using standard artificial image quality metrics and comparative measurements of mineral and Lambertian diffuser standards with standard field and laboratory spectrometers. The proposed algorithm provides highly qualitative results, offers broad applicability through its generic design and might be the first one of its kind to be published. A high radiometric accuracy is achieved by the incorporation of the Reduction of Miscalibration Effects (ROME) framework. The geometric accuracy is higher than 1 μpixel. The critical spectral accuracy was relatively estimated by comparing spectra of standard field spectrometers to those from HySPEX for a Lambertian diffuser. The achieved spectral accuracy is better than 0.02% for the full spectrum and better than 98% for the absorption features. It was empirically shown that point and imaging spectrometers provide different results for non-Lambertian samples due to their different sensing principles, adjacency scattering impacts on the signal and anisotropic surface reflection properties.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

公众号