culture medium

培养基
  • 文章类型: Journal Article
    在科学文献中,抗生素在培养基中的长期稳定性仍未得到充分研究。这项研究评估了八种不同的抗生素储备溶液-阿莫西林的稳定性,头孢噻肟,新霉素,土霉素,氟苯尼考,恩诺沙星,粘菌素,并在37°C的胰蛋白tone大豆肉汤(TSB)中增强了磺酰胺及其10倍稀释系列,超过12天。在制备后立即和在第1、2、5、7、9和12天收集样品,使用超高效液相色谱(UHPLC)结合质谱测定活性物质浓度。结果表明,在超纯水原液中,新霉素,氟苯尼考,和强化磺酰胺保持稳定性(>95%)。在培养基中,氟苯尼考在整个研究中表现出一致的稳定性(100%),强化磺酰胺经历轻微降解(>85%),和新霉素经历了显著降解。阿莫西林,土霉素,粘菌素在两种溶液中都显示出相当大的降解,但在超纯水溶液中更稳定。比较时,头孢噻肟和恩诺沙星在超纯水溶液和培养基中的稳定性非常相似;然而,前者的3.6%和后者的88.7%在第12天仍可检测到。这些发现对于最低抑制浓度(MIC)评估至关重要,特别是在最低杀菌浓度(MBC)研究中,以及关于长期进化和共同选择的实验。这项研究强调了在培养基中进行稳定性评估以验证未来实验结果的必要性。
    The long-term stability of antibiotics in culture media remains underexplored in scientific literature. This study evaluated the stability of eight distinct antibiotic stock solutions-amoxicillin, cefotaxime, neomycin, oxytetracycline, florfenicol, enrofloxacin, colistin, and potentiated sulfonamide-and their 10-fold dilution series in tryptone soy broth (TSB) at 37 °C, over 12 days. Samples were collected immediately after preparation and on days 1, 2, 5, 7, 9, and 12, with active substance concentrations measured using ultra-high-performance liquid chromatography (UHPLC) coupled with mass spectrometry. The results indicated that among the ultrapure water stock solutions, neomycin, florfenicol, and potentiated sulfonamide maintained stability (>95%). Within the culture medium, florfenicol showed consistent stability (100%) throughout the study, potentiated sulfonamide experienced minor degradation (>85%), and neomycin underwent significant degradation. Amoxicillin, oxytetracycline, and colistin displayed considerable degradation in both solution types but were more stable in ultrapure water solutions. The stability of cefotaxime and enrofloxacin in ultrapure water solutions and in the medium was very similar when compared; however, 3.6% of the former and 88.7% of the latter remained detectable by day 12. These findings are crucial for minimum inhibitory concentration (MIC) assessments, especially in minimum bactericidal concentration (MBC) studies, and in experiments concerning long-term evolution and co-selection. This study underscores the necessity of stability assessments in culture media to validate future experimental outcomes.
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  • 文章类型: Journal Article
    多能间充质基质细胞(MSC)在治疗免疫介导的疾病和炎症过程中起着越来越重要的作用。它们通过细胞-细胞接触和分泌各种抗炎分子来调节免疫细胞,但又受到许多因素如细胞因子的影响。对于MSC文化,血小板裂解物(PL),它含有多种细胞因子,是胎牛血清(FBS)的有希望的替代品。我们旨在分析PL及其细胞因子是否能改善MSC免疫调节特征,认为PL可用于在治疗应用之前启动MSC。MSC,活化的外周血单核细胞(PBMC)和两者的间接共培养物在补充有PL的培养基中培养,FBS,FBS+INF-γ或FBS+IL-10。孵化后,在上清液和对照培养基中测量细胞因子浓度。分析MSC的免疫调节基因表达和PBMC的增殖和FoxP3+细胞的百分比。细胞因子,特别是IFN-γ和IL-10在没有细胞的PL对照培养基中保持高水平,但在孵育期间在没有细胞的补充细胞因子的对照FBS培养基中降低。PBMC在各种培养条件下释放IFN-γ和IL-10。MSC仅释放IFN-γ和整体,当单独培养MSC时,培养基中的细胞因子水平最低。通过PBMC或PL刺激MSC导致免疫调节基因的表达改变。在与PBMC的共培养中,MSC基因COX2、TNFAIP6、IDO1、CXCR4和MHC2表达上调,VCAM1表达下调。在PL的存在下,COX2、TNFAIP6、VCAM1、CXCR4和HIF1A上调。功能上,虽然FoxP3+细胞的百分比没有发现一致的变化,MSC减少所有培养基中的PBMC增殖,在补充有IL-10或IFN-γ的FBS培养基中效果最强。这项研究提供了进一步的证据,证明PL支持MSC功能,包括它们的免疫调节机制。结果证明可以更详细地研究在补充PL的培养基中培养的MSC对不同类型的免疫细胞的功能作用。
    Multipotent mesenchymal stromal cells (MSC) play an increasing role in the treatment of immune-mediated diseases and inflammatory processes. They regulate immune cells via cell-cell contacts and by secreting various anti-inflammatory molecules but are in turn influenced by many factors such as cytokines. For MSC culture, platelet lysate (PL), which contains a variety of cytokines, is a promising alternative to fetal bovine serum (FBS). We aimed to analyze if PL with its cytokines improves MSC immunoregulatory characteristics, with the perspective that PL could be useful for priming the MSC prior to therapeutic application. MSC, activated peripheral blood mononuclear cells (PBMC) and indirect co-cultures of both were cultivated in media supplemented with either PL, FBS, FBS+INF-γ or FBS+IL-10. After incubation, cytokine concentrations were measured in supernatants and control media. MSC were analyzed regarding their expression of immunoregulatory genes and PBMC regarding their proliferation and percentage of FoxP3+ cells. Cytokines, particularly IFN-γ and IL-10, remained at high levels in PL control medium without cells but decreased in cytokine-supplemented control FBS media without cells during incubation. PBMC released IFN-γ and IL-10 in various culture conditions. MSC alone only released IFN-γ and overall, cytokine levels in media were lowest when MSC were cultured alone. Stimulation of MSC either by PBMC or by PL resulted in an altered expression of immunoregulatory genes. In co-culture with PBMC, the MSC gene expression of COX2, TNFAIP6, IDO1, CXCR4 and MHC2 was upregulated and VCAM1 was downregulated. In the presence of PL, COX2, TNFAIP6, VCAM1, CXCR4 and HIF1A were upregulated. Functionally, while no consistent changes were found regarding the percentage of FoxP3+ cells, MSC decreased PBMC proliferation in all media, with the strongest effect in FBS media supplemented with IL-10 or IFN-γ. This study provides further evidence that PL supports MSC functionality, including their immunoregulatory mechanisms. The results justify to investigate functional effects of MSC cultured in PL-supplemented medium on different types of immune cells in more detail.
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  • 文章类型: Journal Article
    构建回归模型以从培养基中的近红外光谱预测葡萄糖和乳酸的浓度。采用偏最小二乘(PLS)回归技术,我们研究了使用波长选择和迁移学习可以实现的PLS模型预测能力的提高。我们结合了Boruta,一种基于随机森林的非线性变量选择方法,在PLS中具有变量的投影重要性(VIP),以产生所提出的变量选择方法,VIP-Boruta.此外,重点关注培养基样品和伪培养基样品都可以使用的情况,我们将伪媒体转移到文化媒体。用培养基和伪培养基的实际数据集进行数据分析,证实VIP-Boruta可以有效选择合适的波长,提高PLS模型的预测能力,伪媒体迁移学习增强了预测能力。所提出的方法可以将葡萄糖的预测误差降低约61%,乳酸的预测误差降低约16%。与传统的PLS模型相比。
    Regression models are constructed to predict glucose and lactate concentrations from near-infrared spectra in culture media. The partial least-squares (PLS) regression technique is employed, and we investigate the improvement in the predictive ability of PLS models that can be achieved using wavelength selection and transfer learning. We combine Boruta, a nonlinear variable selection method based on random forests, with variable importance in projection (VIP) in PLS to produce the proposed variable selection method, VIP-Boruta. Furthermore, focusing on the situation where both culture medium samples and pseudo-culture medium samples can be used, we transfer pseudo media to culture media. Data analysis with an actual dataset of culture media and pseudo media confirms that VIP-Boruta can effectively select appropriate wavelengths and improves the prediction ability of PLS models, and that transfer learning with pseudo media enhances the predictive ability. The proposed method could reduce the prediction errors by about 61% for glucose and about 16% for lactate, compared to the traditional PLS model.
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  • 文章类型: Journal Article
    传统的细胞系模型是肺癌研究中常用的临床前模型。然而,细胞系不能概括复杂的肿瘤异质性,也不能模拟人类癌症的微环境。最近,称为“类器官”的3D多细胞体外自组装模型在研究领域得到了快速发展,可以模拟实际的原发性肿瘤。目前,一些研究报道了肺癌类器官(LCOs)产生的协议,使用LCO可以为肺癌的基础和转化研究提供新的见解。然而,由于肺癌的复杂性和类器官技术的不成熟,LCO模型的建立仍然具有挑战性,因此,有必要了解不同方法对LCO生成的影响,并回顾LCO模型的应用和局限性。
    在这篇评论中,我们检索了近十年来LCO领域的文献。
    我们总结了方法论,问题,以及LCO一代中的解决方案,它的应用和局限性,并提出未来的挑战和前景。
    目前,LCO是通过研究人员探索方法成功生成的。尽管在临床应用中仍然存在挑战,LCO应用于一些癌症研究,包括体外抗癌治疗反应的研究,模拟肿瘤免疫微环境,和器官芯片的构建,正在为精准医学开辟一条有希望的道路。
    UNASSIGNED: Traditional cell line models are the commonly used preclinical models for lung cancer research. However, cell lines cannot recapitulate the complex tumor heterogeneity and cannot mimic the microenvironment of human cancer. Recently, 3D multicellular in vitro self-assembled models called \"organoids\" have been developed at a fast pace in the field of research, which can mimic the actual primary tumor. At present, several studies have reported on protocols of lung cancer organoids (LCOs) generation, and using LCOs can provide novel insight into the basic and translational research of lung cancer. However, the establishment of the LCO models remains challenging due to the complexity of lung cancer and the immaturity of organoid technology, so it is necessary to understand the influences of different methodologies on LCO generation and review the applications and limitations of LCO models.
    UNASSIGNED: In this review, we searched the literature in the recent ten years in the field of LCOs.
    UNASSIGNED: We summarized the methodology, the problems, and the solutions in the LCOs generation, its application and limitations, as well as proposing future challenges and perspectives.
    UNASSIGNED: Currently, LCOs are successfully generated via exploring the methodology by the researchers. Though there are still challenges in clinical application, LCOs are applied in some cancer studies including investigation of anti-cancer treatment response in vitro, modeling tumor immune microenvironment, and construction of organ chips, which are forging a promising path towards precision medicine.
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  • 文章类型: Journal Article
    多能干细胞(PSC),包括胚胎干细胞(ESC)和诱导多能干细胞(iPSC),由于它们能够分化成成人身体的所有细胞类型,因此为再生医学提供了巨大的潜力。利用这种潜力的一个关键方面是了解它们在衍生过程中的代谢需求,维护,和体外分化。使用胎牛血清的传统培养方法通常导致诸如异质细胞群体和多能性降低的问题。尽管化学定义的2i/LIF培养基为这些挑战中的一些提供了解决方案,这些细胞的长期培养,尤其是女性ESC,引起了与基因组完整性相关的担忧。这篇综述讨论了脂质在干细胞基因组稳定性和多能性中的关键作用。值得注意的是,引入富含脂质的白蛋白,阿尔布麦克斯,加入2i/LIF培养基为增强培养的ESC的基因组稳定性和多能性提供了有希望的途径。我们进一步探索脂质诱导多能干细胞(LIP-ESCs)的独特特征,强调他们在再生医学和多能性研究中的潜力。
    Pluripotent stem cells (PSCs), comprising embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), offer immense potential for regenerative medicine due to their ability to differentiate into all cell types of the adult body. A critical aspect of harnessing this potential is understanding their metabolic requirements during derivation, maintenance, and differentiation in vitro. Traditional culture methods using fetal bovine serum often lead to issues such as heterogeneous cell populations and diminished pluripotency. Although the chemically-defined 2i/LIF medium has provided solutions to some of these challenges, prolonged culturing of these cells, especially female ESCs, raises concerns related to genome integrity. This review discusses the pivotal role of lipids in genome stability and pluripotency of stem cells. Notably, the introduction of lipid-rich albumin, AlbuMAX, into the 2i/LIF culture medium offers a promising avenue for enhancing the genomic stability and pluripotency of cultured ESCs. We further explore the unique characteristics of lipid-induced pluripotent stem cells (LIP-ESCs), emphasizing their potential in regenerative medicine and pluripotency research.
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  • 文章类型: Journal Article
    微藻和大型藻类的发酵是获得有价值的增值产品的最有效方法之一,由于环境污染最小和经济效益的可利用性,由于藻类不需要耕地和漂移藻类和藻类的生物量被认为是废物,必须回收和利用其发酵废物。藻类中发现的化合物可以有效地用于燃料中,食物,化妆品,和制药工业,取决于使用的发酵类型。甲烷和氢气等产品可以通过厌氧消化和藻类的黑暗发酵产生,乳酸及其聚合物可以通过藻类的乳酸发酵生产。文章旨在概述微藻和大型藻类发酵的不同类型潜力,考虑每种类型的优缺点,和藻类发酵生产各种增值产品的经济可行性。
    Fermentation of both microalgae and macroalgae is one of the most efficient methods of obtaining valuable value-added products due to the minimal environmental pollution and the availability of economic benefits, as algae do not require arable land and drift algae and algal bloom biomass are considered waste and must be recycled and their fermentation waste utilized. The compounds found in algae can be effectively used in the fuel, food, cosmetic, and pharmaceutical industries, depending on the type of fermentation used. Products such as methane and hydrogen can be produced by anaerobic digestion and dark fermentation of algae, and lactic acid and its polymers can be produced by lactic acid fermentation of algae. Article aims to provide an overview of the different types potential of micro- and macroalgae fermentation, the advantages and disadvantages of each type considered, and the economic feasibility of algal fermentation for the production of various value-added products.
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  • 文章类型: Journal Article
    背景:尽管有长期的研究历史和持续的临床试验努力,间充质基质细胞(MSC)疗法的市场授权数量仍然有限,没有得到美国食品和药物管理局的批准。一些障碍阻碍了MSC治疗的临床进展,其中最重要的是缺乏标准化的制造方案,这进一步加剧了缺乏生物学上有意义的表征和释放测定。观察临床试验注册证明了MSC扩增方案的多样性,具有细胞来源的可变性,隔离方法和膨胀介质,在其他文化变量中,这使得比较研究结果变得非常困难。目前的鉴定和表征标准是不够的;它们不是MSC特异性的,并且不指示细胞功能或治疗作用。
    方法:这项工作分析了五种广泛使用的培养基配方对菌落形成潜力的影响,增殖动力学,人骨髓来源的MSCs(BM-MSCs)的三系分化潜能和免疫调节潜能。还使用243个标记的高含量流式细胞术筛选组来表征表面标记表达谱。
    结果:BM-MSCs的生物学属性存在显著差异,包括克隆性,扩散,响应于培养基的组成,揭示了分化倾向和免疫调节能力。尽管它们的生物学差异,所有细胞制剂均一致且强烈地表达针对BM-MSC提出的标准阳性标志物:CD73、CD90和CD105。免疫表型分析显示,培养基对表面蛋白质组也有显著影响,三分之一的测试标记物表现出可变的表达谱。主成分分析表明,与血小板裂解物和含有胎牛血清的培养基相比,在专有的无异种和无血清培养基中分离和扩增的BM-MSC表现出最一致的细胞表型,供体之间几乎没有变异性。
    结论:这些数据表明培养基组成对MSCs的生物学特性具有非常显著的影响,但是标准表面标记测试掩盖了这些差异。结果表明,需要(1)标准化的制造方法,主要关注确定的培养基和(2)MSC表征和产品释放的新的生物学相关测试。
    Despite a long history of investigation and sustained efforts in clinical testing, the number of market authorisations for mesenchymal stromal cell (MSC) therapies remains limited, with none approved by the United States Food and Drug Administration. Several barriers are impeding the clinical progression of MSC therapies, to the forefront of these is a lack of standardised manufacturing protocols which is further compounded by an absence of biologically meaningful characterisation and release assays. A look at clinical trial registries demonstrates the diversity of MSC expansion protocols with variabilities in cell source, isolation method and expansion medium, among other culture variables, making it extraordinarily difficult to compare study outcomes. Current identification and characterisation standards are insufficient; they are not specific to MSCs and do not indicate cell function or therapeutic action.
    This work analysed the influence of five widely used culture media formulations on the colony-forming potential, proliferation kinetics, trilineage differentiation potential and immunomodulatory potential of human bone marrow-derived MSCs (BM-MSCs). The surface marker expression profiles were also characterised using a high-content flow cytometry screening panel of 243 markers.
    Significant differences in the biological attributes of BM-MSCs including clonogenicity, proliferation, differentiation propensity and immunomodulatory capacity were revealed in response to the composition of the culture medium. Despite their biological differences, all cell preparations uniformly and strongly expressed the standard positive markers proposed for BM-MSCs: CD73, CD90 and CD105. Immunophenotypic profiling revealed that the culture medium also had a significant influence on the surface proteome, with one-third of tested markers exhibiting variable expression profiles. Principal component analysis demonstrated that BM-MSCs isolated and expanded in a proprietary xeno- and serum-free medium displayed the most consistent cell phenotypes with little variability between donors compared to platelet lysate and foetal bovine serum-containing media.
    These data suggest that media composition has a highly significant impact on the biological attributes of MSCs, but standard surface marker tests conceal these differences. The results indicate a need for (1) standardised approaches to manufacturing, with an essential focus on defined media and (2) new biologically relevant tests for MSC characterisation and product release.
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  • 文章类型: Journal Article
    食用葡萄的新趋势以及对这种作物对环境的影响越来越感兴趣,这促使育种者朝着具有抗性的无核品种发展。通过杂交计划。为了获得无核葡萄,胚胎拯救技术的使用是至关重要的。在这项研究中,通过在2017-2021年期间在私人网络意大利品种俱乐部的大型私人鲜食葡萄计划的框架内进行的39个品种和41个交叉组合,对葡萄胚胎培养协议进行了优化和验证,评估了几个因素,例如胚胎形成的改善,发芽和生长,和植株发育。评估了无核亲本不同组合之间杂交的胚胎培养态度,提取的胚珠的胚胎发育率大多在3.5%至35.5%之间,43个基因型中有5个异常值。在不同采样时间进行的实验,在授粉后(DAP)的43-62天范围内,分析的样品之间没有显着差异,虽然应用方案开发的胚胎率证明了其在多种基因型上的适用性,尽管葡萄藤基因型显着影响技术效率。
    The new trends in the consumption of table grapes and the growing interest in the environmental impact of this crop have pushed breeders toward the development of seedless cultivars endowed with resistance, through crossbreeding programs. To obtain seedless grapes, the use of embryo-rescue techniques is fundamental. In this research, a grape embryo-culture protocol was optimized and validated by using 39 cultivars and 41 cross-combinations carried out in the framework of a large private table grape program of the private network Italian Variety Club in the period 2017-2021 evaluating several factors, such as the improvement in embryo formation, germination and growth, and plantlet development. The embryo culture attitude of crosses between different combinations of seedless parents was assessed, and the rates of embryo development from the extracted ovules mostly ranged from 3.5 to 35.5% with 5 out of 43 genotypes outliers. Experiments conducted at different sampling times, in a range of 43-62 days after pollination (DAP), did not show significant differences between the samples analyzed, while the rate of embryos developed with the applied protocol proved its employability on multiple genotypes, although the grapevine genotype significantly influenced the technique efficiency.
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  • 文章类型: Journal Article
    探索细胞维持自由生活的最低遗传要求是生物学中一个令人兴奋的话题。采用多种方法来解决最小基因组的问题。除了在试管中构建合成基因组,减小野生型基因组的大小是获得活细胞必需基因组序列的实用方法。经过充分研究的大肠杆菌由于其快速生长和易于操作而被用作基因组减少的模型生物。广泛的研究已经报道了如何减少细菌基因组和基因组扰动菌株的集合,之前已经进行了充分的审查。然而,遗传干扰引起的生长减少的常见问题仍未解决。这篇小型评论讨论了为改善生长适应性所做的大量努力,由于基因组减少而减少。阐明了进一步积累的遗传缺失的建议和观点,以减少基因组减少方面的大肠杆菌基因组,实验进化,介质优化,和机器学习。
    Exploring the minimal genetic requirements for cells to maintain free living is an exciting topic in biology. Multiple approaches are employed to address the question of the minimal genome. In addition to constructing the synthetic genome in the test tube, reducing the size of the wild-type genome is a practical approach for obtaining the essential genomic sequence for living cells. The well-studied Escherichia coli has been used as a model organism for genome reduction owing to its fast growth and easy manipulation. Extensive studies have reported how to reduce the bacterial genome and the collections of genomic disturbed strains acquired, which were sufficiently reviewed previously. However, the common issue of growth decrease caused by genetic disturbance remains largely unaddressed. This mini-review discusses the considerable efforts made to improve growth fitness, which was decreased due to genome reduction. The proposal and perspective are clarified for further accumulated genetic deletion to minimise the Escherichia coli genome in terms of genome reduction, experimental evolution, medium optimization, and machine learning.
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  • 文章类型: Journal Article
    土壤细菌Burkholderiapseudomallei导致类石病,一种潜在致命且严重未被诊断的热带病。检测环境中的假单胞菌对追踪感染源很重要,确定类lioidosis的风险区域并提高临床意识。尽管基于聚合酶链反应(PCR)的环境检测提供了重要信息,病原体的培养仍然是必不可少的,但仍然是方法上的挑战。假单胞菌可以分解代谢赤藓糖醇,一种代谢途径,否则在细菌中很少遇到。我们最近证明,在历史上使用的pH中性苏氨酸基础盐溶液(TBSS-C50)中,用赤藓糖醇代替苏氨酸作为单一碳源可以改善从稻田土壤中分离假单胞菌。然而,从土壤中优化回收假单胞菌菌株的进一步培养基参数仍然不确定。我们,因此,旨在通过系统地优化pH等参数来设计一种新的赤藓糖醇基培养基,缓冲能力,盐和营养成分。我们研究的一个关键发现是在酸性培养基条件下假单胞菌的基于赤藓糖醇的生长增强。我们使用来自不同地理来源的假单胞菌菌株进行的实验导致开发了pH为6.3,赤藓糖醇浓度为1.2%的磷酸盐缓冲酸性赤藓糖醇(ACER)培养基,补充维生素和硝酸盐。与基于TBSS-C50和TBSS-C50的赤藓糖醇培养基相比,这种高度选择性的培养基组合物缩短了假单胞菌培养物的滞后期,并大大提高了生长密度。在与来自越南中部的土壤样品的比较验证中,通过定量PCR从培养上清液中确定,ACER培养基导致最高的假单胞菌富集。因此,ACER继代培养的Ashdown's琼脂上的假单胞菌菌落形成单位的平均回收率是基于TBSS-C50的赤藓糖醇培养基的5.4倍(p=0.005)和TBSS-C50的30.7倍(p<0.001)。总之,我们新开发的ACER培养基显着改善了从土壤中分离活的假单胞菌,因此,有可能降低类霉菌病风险地区环境培养的假阴性率。
    The soil bacterium Burkholderia pseudomallei causes melioidosis, a potentially fatal and greatly underdiagnosed tropical disease. Detection of B. pseudomallei in the environment is important to trace the source of infections, define risk areas for melioidosis and increase the clinical awareness. Although B. pseudomallei polymerase chain reaction (PCR)-based environmental detection provides important information, the culture of the pathogen remains essential but is still a methodological challenge. B. pseudomallei can catabolize erythritol, a metabolic pathway, which is otherwise rarely encountered among bacteria. We recently demonstrated that replacing threonine with erythritol as a single carbon source in the pH-neutral threonine-basal salt solution (TBSS-C50) historically used improved the isolation of B. pseudomallei from rice paddy soils. However, further culture medium parameters for an optimized recovery of B. pseudomallei strains from soils are still ill-defined. We, therefore, aimed to design a new erythritol-based medium by systematically optimizing parameters such as pH, buffer capacity, salt and nutrient composition. A key finding of our study is the enhanced erythritol-based growth of B. pseudomallei under acidic medium conditions. Our experiments with B. pseudomallei strains from different geographical origin led to the development of a phosphate-buffered acidic erythritol (ACER) medium with a pH of 6.3, higher erythritol concentration of 1.2%, supplemented vitamins and nitrate. This highly selective medium composition shortened the lag phase of B. pseudomallei cultures and greatly increased growth densities compared to TBSS-C50 and TBSS-C50-based erythritol medium. The ACER medium led to the highest enrichments of B. pseudomallei as determined from culture supernatants by quantitative PCR in a comparative validation with soil samples from the central part of Vietnam. Consequently, the median recovery of B. pseudomallei colony forming units on Ashdown\'s agar from ACER subcultures was 5.4 times higher compared to TBSS-C50-based erythritol medium (p = 0.005) and 30.7 times higher than TBSS-C50 (p < 0.001). In conclusion, our newly developed ACER medium significantly improves the isolation of viable B. pseudomallei from soils and, thereby, has the potential to reduce the rate of false-negative environmental cultures in melioidosis risk areas.
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