微生物传感器在食品分析中的应用

微生物传感器是以活体微生物细胞为感应元件, 感应需要测定的靶标物质浓度并按照一定规律转换为可识别信号的检测装置。早期的微生物传感器以微生物测定和微生物电极的形式出现, 近年来随着分子生物学和合成生物学技术的进步, 基因工程类微生物传感器迅速发展, 并且由于其成本低、使用便捷、功能扩展性强等优势, 使其在食品安全领域具有良好的应用潜力。本文介绍了微生物传感器的发展历程和基本原理, 总结了微生物传感器在食品安全检测、食品品质分析、食品安全毒性评估、食品污染脱毒等方面的最新研究成果, 分析了微生物传感器发展趋势和当前的技术瓶颈。本综述可为食品安全快速检测技术研究和应用人员提供信息和技术参考, 推动微生物传感器领域的进一步发展。     

浏阳洞库陈化烟叶微生物多样性分析

[目的]为研究浏阳洞库3个不同香型陈化烟叶样品微生物多样性和群落组成差异.[方法]利用高通量测序对3个不同香型陈化烟叶样品微生物多样性、群落组成进行显著性差异分析,构建各样品微生物生态网络,并对各细菌群落进行功能预测.[结果](1)浏阳洞库3个不同香型陈化烟叶样品中细菌物种丰富,在门水平上主要由变形菌门和厚壁菌门组成,...     

Interpreting deposition patterns of microbial particles in laboratory-scale column experiments

The transport and fate of microbial particles in subsurface environments is controlled by their capture (natural filtration) by sediment grains. Typically, filtration models used to describe microbe removal in porous media predict exponential decrease in microbial particle concentration with travel distance. However, a growing body of laboratory-scale column experiments suggests that the retained microbial particle profiles decay nonexponentially. The observed behavior may be attributed to the heterogeneity in the interactions between microbial particles and sediment grains, most likely due to the inherent variability in the microbial particles. This factor can be incorporated into classical colloid filtration (deposition) theory by inclusion of a distribution in the deposition rate coefficient. We show that certain distributions of the deposition rate coefficient (i.e., log-normal, bimodal, and power-law distributions) give rise to nonexponential deposition patterns. Comparisons of model predictions to experimental data indicate that the observed nonexponential deposition behavior of bacteria and virus particles may be attributed to a broad range (i.e., a power-law distribution) of microbial deposition rates. Other mechanisms such as particle release and blocking by previously deposited microbial particles are also shown to be potential sources of deviation from the classical filtration theory. Our results further suggest that monitoring fluid-phase particle concentration is insufficient for accurate characterization of the deposition and transport behavior of microbial particles in saturated porous media. Rather, the shape of the microbial particle retention profile is shown to be a key indicator of the mechanisms controlling microbial deposition and transport.     

包装饮用水生产工艺过程微生物污染的检测与评估

为全面了解包装饮用水生产工艺中微生物的污染现状,从生产工艺过程各环节中采集样品,进行微生物培养,然后分离并纯化菌株进行微生物菌种鉴定,以掌握其背景资料,从而为合理、有效地控制生产工艺中潜在的微生物危害提供科学依据。     

传统腌腊肉制品中微生物多样性及其功能研究进展

传统腌腊肉制品中微生物组成复杂多样,并已被证实与产品独特风味的形成密不可分。近年来应用新技术手段研究腌腊肉制品中的微生物多样性以及挖掘其功能已成为趋势和热点。深刻理解传统腌腊肉制品微生物多样性及其功能特性的科学内涵对于提升我国传统腌腊肉制品品质,实现其工业化改造升级具有重要意义。本文就我国传统腌腊肉制品微生物多样性研究方法及其优势菌群、微生物功能特性进行综述,并对腌腊肉制品的微生物研究发展方向进行展望。     

NADPH代谢对氨基酸生物合成影响的研究进展

烟酰胺腺嘌呤二核苷酸磷酸（nicotinamide adenine dinucleotide phosphate,NADPH）是微生物代谢重要的辅助因子,其在微生物体内的含量是限制氨基酸合成代谢的一个重要因素。本文从NADPH的生物代谢,NADPH与微生物发酵产氨基酸的关系,以及NADPH的代谢调控策略促进氨基酸的生物合成等,进行简要概述,为进一步提高氨基酸产量提供参考。     

酱香大曲间微生物群落结构时空特征的表征

为比较不同区域、企业、场地及陈曲时间所得酱香型大曲的微生物群落多样性特征差异,本文描述了应用Illumina MiSeq 2×300研究6种不同类型的14个酱香型大曲样品的微生物群落组成。结果表明,优势微生物属于4个不同细菌目和真菌目,其相对丰度分别超过了96.48%和79.75%。芽胞杆菌目(Bacillales)、肠杆菌目(Enterobacteriales)、乳杆菌目(Lactobacillales)和放线菌目(Actinomycetales)等为优势细菌目,优势真菌则是酵母菌目(Saccharomycetales)、肉座菌目(Hypocreales)、散子囊菌目(Eurotiales)和丝孢酵母目(Trichosporonales)。这些样品检测结果的聚类和非度量多维测度(NMDS)的分析显示,茅台镇与其它类型的样品间其曲心群落多样性差异明显,前者的葡萄球菌属(Staphylococcus)、芽孢杆菌属(Bacillus)、片球菌属(Pediococus)、假丝酵母属(Candida),曲霉属(Aspergillus)等属微生物丰度较高。在二郎镇地区生产的酱曲香大曲的群落结构组成也不同,陈曲时间也致使其群落多样性呈现差异。这些结果揭示了酱香型大曲的微生物群落具有显著的时空性特征。     

微生物絮凝剂研究进展及其在食品工业中的应用

在食品工业污水处理中,传统化学絮凝剂被广泛应用,但其本身有剧毒,且不易被环境降解,这大大提高了污水处理副产物回收再利用的难度。微生物絮凝剂是一类由微生物代谢产生的,具有絮凝能力的高分子有机物。因其具有无毒和可生物降解等优点,使其成为了传统化学絮凝剂潜在替代品。该文主要介绍了近年来微生物絮凝剂的发展趋势,并从微生物絮凝剂的化学组成、絮凝机理、絮凝剂产生菌的筛选、培养条件的优化以及微生物絮凝剂在食品工业领域的应用等方面进行综述。     

肉及肉制品微生物检测新技术研究进展

肉及肉制品营养丰富,也易受微生物污染,其食用安全性备受关注。本文介绍肉及肉制品中微生物限量要求,分析传统微生物检测方法的弊端,综述快速测试片法、三磷酸腺苷生物荧光法、分子诊断法、免疫分析法、光谱法、仪器法等新技术在肉及肉制品中微生物检测应用中的研究进展,以期为国内学者开展相关研究提供参考,满足肉类产业对微生物检测快速、准确的需求,为肉类企业减轻流通压力并降低由此带来的经济损失。     

Effect of chemicals on the microbial evolution in foods

In contrast with most chemical hazardous compounds, the concentration of food pathogens changes during processing, storage, and meal preparation, making it difficult to estimate the number of microorganisms or the concentration of their toxins at the moment of ingestion by the consumer. These changes are attributed to microbial proliferation, survival, and/or inactivation and must be considered when exposure to a microbial hazard is assessed. The number of microorganisms can also change as a result of physical removal, mixing of food ingredients, partitioning of a food product, or cross-contamination (M. J. Nauta. 2002. Int. J. Food Microbiol. 73:297-304). Predictive microbiology, i.e., relating these microbial evolutionary patterns to environmental conditions, can therefore be considered a useful tool for microbial risk assessment, especially in the exposure assessment step. During the early development of the field (late 1980s and early 1990s), almost all research was focused on the modeling of microbial growth over time and the influence of temperature on this growth. Later, modeling of the influence of other intrinsic and extrinsic parameters garnered attention. Recently, more attention has been given to modeling of the effects of chemicals on microbial inactivation and survival. This article is an overview of different applied strategies for modeling the effect of chemical compounds on microbial populations. Various approaches for modeling chemical growth inhibition, the growth-no growth interface, and microbial inactivation by chemicals are reviewed.     

宏基因组学在普洱茶微生物研究中的应用

宏基因组学(metagenomics)又叫微生物环境基因组学。通过从环境样品中提取全部微生物的DNA从而构建宏基因组文库,利用基因组学研究环境样品中所包含的全部微生物的遗传组成及其群落功能。它是在微生物基因组学的基础上发展起来的一种研究微生物多样性、开发新的生理活性物质(或获得新基因)的新理念和新方法。近几年宏基因技术广泛应用于微生物研究。本研究就宏基因组学应用于普洱茶微生物群落结构及其动态变化等方面进行总结,展望宏基因组学应用于普洱茶微生物研究的发展前景。     

Predictive modelling of the growth and survival of Listeria in fishery products

Predictive microbiology provides a powerful tool to aid the exposure assessment phase of 'quantitative microbial risk assessment'. Using predictive models changes in microbial populations on foods between the point of production/harvest and the point of eating can be estimated from changes in product parameters (temperature, storage atmosphere, pH, salt/water activity, etc.). Thus, it is possible to infer exposure to Listeria monocytogenes at the time of consumption from the initial microbiological condition of the food and its history from production to consumption. Predictive microbiology models have immediate practical application to improve microbial food safety and quality, and are leading to development of a quantitative understanding of the microbial ecology of foods. While models are very useful decision-support tools it must be remembered that models are, at best, only a simplified representation of reality. As such, application of model predictions should be tempered by previous experience, and used with cognisance of other microbial ecology principles that may not be included in the model. Nonetheless, it is concluded that predictive models, successfully validated in agreement with defined performance criteria, will be an essential element of exposure assessment within formal quantitative risk assessment. Sources of data and models relevant to assessment of the human health risk of L. monocytogenes in seafoods are identified. Limitations of the current generation of predictive microbiology models are also discussed. These limitations, and their consequences, must be recognised and overtly considered so that the risk assessment process remains transparent. Furthermore, there is a need to characterise and incorporate into models the extent of variability in microbial responses. The integration of models for microbial growth, growth limits or inactivation into models that can predict both increases and decreases in microbial populations over time will also improve the utility of predictive models for exposure assessment. All of these issues are the subject of ongoing research.     

合成微生物群落及在发酵食品中应用研究进展

合成微生物群落是指在明确培养基质的条件下,人工将两种或两种以上遗传背景完全解析的微生物通过共同培养而形成的微生物群体,其可通过微生物间的相互作用实现特定的功能,具有复杂度低、可控性强、稳定性好等优点。该文对合成微生物群落的特征、微生物之间的相互作用和调控机制以及其在发酵食品酱油、白酒、食醋和酸奶中的应用进行了概述,并对如何构建稳定、高效的发酵微生物群落进行了展望,旨在为合成微生物群落在发酵食品行业的进一步深入研究及开发应用提供参考。     

宏基因组学及其在大曲酒微生物研究中的应用

利用宏基因组学技术可以直接从基因水平上研究大曲酒生产微生物群落,研究发酵过程中微生物群落的消长及变化,特别是对大曲酒微生物群落的功能菌及多酶体系的认识,全面了解大曲酒微生物群落的代谢机理和形成大曲酒与众不同的香味组分的构成和风味特征.     

纯生啤酒生产过程中的工艺控制

纯生啤酒生产的关键是纯种酿造和后期对微生物污染的有效控制。对此必须对生产工艺、设备、人员及生产环境等各方面严格把关、严格控制。主要控制有：添加酵母过程微生物污染、原料微生物污染、酿造设备及仪器微生物污染的控制；后期过滤过程的微生物污染的控制；清酒的微生物控制；灌装车间的洗瓶机、验瓶机、灌装封盖机、瓶装输送线的微生物控制等。(孙悟)     

2016年广东省6类食品不同微生物污染情况分析

目的 为了解广东省流通食品的微生物污染状况。方法 采用GB 4789-2010《食品安全国家标准 食品微生物学检验》对2016年检验的6类食品进行微生物（菌落总数、大肠菌群、霉菌和酵母菌、致病菌）检验,对检验结果进行统计分析。结果 3216份样品中共检出不合格样品39份,总体合格率为98.79%。不同微生物项目的检验结果中,菌落总数的合格率相对最低,为99.19%。检验的6类食品中速冻食品、方便食品和水产制品检出不合格样品,方便食品的合格率（97.2%）相对最低。结论 广东省食品微生物污染整体状况较好,建议对微生物污染风险较高的方便食品、水产制品进行重点关注,采取有效措施降低食品微生物污染的风险。     

微生物分子生态学研究方法概述

微生物分子生态学是分子生物学与微生物生态学交叉而形成的学科,对于认识微生物生态系统组成结构、功能、微生物之间以及微生物与环境之间的相互关系具有重要意义。本文以微生物分子生态学研究方法作为切入点,对目前广泛使用的微生物分子生态学研究技术和方法进行综合介绍、分析和总结,对各种方法的优缺点和应用进行评论,以期为认识和调控生态系统的微生物群落提供参考。     

2018年云南省臭豆腐微生物污染监测结果分析

目的 了解和分析云南省臭豆腐微生物污染状况及存在的风险隐患。方法 在云南省内从农贸市场、零售及餐饮等环节,采集生、熟臭豆腐样本384件,对大肠埃希氏菌、金黄色葡萄球菌、蜡样芽胞杆菌、沙门氏菌、变形杆菌等微生物指标进行监测分析。结果 样品微生物污染阳性检出率为49.74%(191/384),食源性致病菌阳性样品检出率为28.13%(108/384),其中沙门氏菌不合格率0.52%(2/384)、金黄色葡萄球菌不合格率0.26%(1/384)、蜡样芽胞杆菌检不合格率1.30%(5/384)、变形杆菌检出率21.88%(84/384)。生、熟臭豆腐微生物污染阳性检出率存在显著差异(P<0.05)。结论 云南省臭豆腐存在较高的微生物污染,相关部门应加强监管,加快制订相应食品安全标准,以预防和控制食源性疾病的发生。     

高通量测序在食品微生物生态学研究中的应用

随着分子生物学的发展,越来越多新的研究投入到对食品微生物的研究中。高通量测序作为一种新兴的分子生物学技术,具有数据产出通量高、分析全面、灵敏、快速等特点,被广泛用于食品微生物生态学的研究中。本文对高通量测序的操作流程及其在食品微生物生态学研究中的应用进行总结,评价该技术的优势和局限性,并对其在食品微生物研究中的应用前景进行展望,以期为食品微生物生态学的研究提供参考。     

Isoprenoid quinones as biomarkers of microbial populations in the environment

Isoprenoid quinones are lipid molecules present in all species of respiratory and photosynthetic microorganisms and exhibit marked structural variations depending upon the microbial taxon. Taking advantage of this, quinones have been used not only as chemotaxonomic markers in microbial systematics but also as good measures of microbial populations in the environment in terms of quantity, quality, and activity. Basically, this biomarker approach, called the quinone profile method, is applicable to all environmental samples from which an absolute amount of microbial biomass > or =10(9) cells can be collected. The quinone profile method allows good measurement of both fundamental and applied aspects of ecological and environmental microbiology. In particular, numerical cluster analyses of quinone profiles are useful for monitoring microbial population shifts in an ecosystem which is not amenable to conventional culture methods and molecular techniques. The combined use of molecular techniques and the quinone profile method in this research area should provide more accurate and reliable data regarding population dynamics and community structures.