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101.
郫县豆瓣发酵过程的微生物多样性及溯源分析 总被引:1,自引:1,他引:0
[目的] 解析郫县豆瓣及其酿造半成品-蚕豆醅与辣椒醅微生物多样性和来源,探究郫县豆瓣酿造过程风味化合物特征。[方法] 采用高通量测序法测定蚕豆醅、辣椒醅与混合醅(蚕豆醅-辣椒醅混合物,发酵成熟形成郫县豆瓣)在酿造过程中的微生物群落结构;利用高效气相质谱与高效液相色谱高通量检测蚕豆醅及辣椒醅中基础理化指标及挥发性、非挥发性风味化合物浓度;利用多种生物信息学分析方法对混合醅酿造微生物及风味化合物进行溯源。[结果] 微生物方面:44%–59%的混合醅细菌来源于辣椒醅,5%–22%的混合醅细菌来源于蚕豆醅,其他混合醅细菌来源未知。同时,42%–77%的混合醅真菌来源于辣椒醅,2%–18%的混合醅真菌来源于蚕豆醅,其他混合醅真菌来源未知。另外,16个细菌属由辣椒醅特异性贡献;2个细菌属及2个真菌属由蚕豆醅特异性贡献。化合物方面:1-辛烯-3醇(1-octen-3-ol)、苯乙醛(phenylacetaldehyde)、异丁醛(isobutyraldehyde)、苹果酸(malic acid)与糠醛(furfural)仅由蚕豆醅贡献。辣椒素(capsaicin)、3-甲基-1-丁醇(3-methyl-1-butanol)、已醇(hexanol)与异丁醇(isobutanol)仅由辣椒醅贡献。[结论] 郫县豆瓣发酵中大部分微生物来源于辣椒醅,大部分发酵底物(氨基酸及葡萄糖)来源于蚕豆醅。两种发酵半成品均特异性贡献微生物及风味化合物,形成郫县豆瓣的独特风味密码。 相似文献
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Quantifying non-point source (NPS) phosphorus (P) pollution loads is essential for watershed nutrients management. This study intended to develop a NPS P indicator which (1) was suitable in semi-humid and semi-arid watersheds of Northern China; (2) integrated the key NPS P loss factors and constructed them in a simple and physically understandable way and (3) kept P loss forms distinctively separate. An inverse distance-based delivery ratio was proposed to count for the P delivery efficiency from source to watercourses. We applied this P indicator in Luan River Watershed (LRW) of northern China under typical hydrological years and seasons. Results demonstrated that this NPS P indicator predicted reasonable NPS TP loads using simple methods and readily obtainable inputs. The sub-watersheds located in the south of LRW were recognized as the high risk areas of NPS P loss to Panjiakou reservoir. The upland and paddy fields near the river channels were particularly posing high risk and thus should be treated with prioritized management practices such as soil conservation and recommended fertilization. Rainfall-runoff related variables rather than P source variables explained more of the spatial variation in NPS P load and percentages. Using this tool could give policy makers insight into the component and location of NPS P pollution that needs to be the focus of policy at watershed scales before sophisticated studies were conducted in smaller scales. 相似文献
105.
Development of antifouling strategies requires knowledge of how fouling organisms would respond to climate change associated environmental stressors. Here, a calcareous tube built by the tubeworm, Hydroides elegans, was used as an example to evaluate the individual and interactive effects of ocean acidification (OA), warming and reduced salinity on the mechanical properties of a tube. Tubeworms produce a mechanically weaker tube with less resistance to simulated predator attack under OA (pH 7.8). Warming (29°C) increased tube volume, tube mineral density and the tube’s resistance to a simulated predatory attack. A weakening effect by OA did not make the removal of tubeworms easier except for the earliest stage, in which warming had the least effect. Reduced salinity (27 psu) did not affect tubes. This study showed that both mechanical analysis and computational modeling can be integrated with biofouling research to provide insights into how fouling communities might develop in future ocean conditions. 相似文献
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Climate change refugia in the terrestrial biosphere are areas where species are protected from global environmental change and arise from natural heterogeneity in landscapes and climate. Within the marine realm, ocean acidification, or the global decline in seawater pH, remains a pervasive threat to organisms and ecosystems. Natural variability in seawater carbon dioxide (CO2) chemistry, however, presents an opportunity to identify ocean acidification refugia (OAR) for marine species. Here, we review the literature to examine the impacts of variable CO2 chemistry on biological responses to ocean acidification and develop a framework of definitions and criteria that connects current OAR research to management goals. Under the concept of managing vulnerability, the most likely mechanisms by which OAR can mitigate ocean acidification impacts are by reducing exposure to harmful conditions or enhancing adaptive capacity. While local management options, such as OAR, show some promise, they present unique challenges, and reducing global anthropogenic CO2 emissions must remain a priority. 相似文献
108.
C. García-Aljaro A.R. Blanch C. Campos J. Jofre F. Lucena 《Journal of applied microbiology》2019,126(3):701-717
The objective of this review is to assess the current state of knowledge of pathogens, general faecal indicators and human-specific microbial source tracking markers in sewage. Most of the microbes present in sewage are from the microbiota of the human gut, including pathogens. Bacteria and viruses are the most abundant groups of microbes in the human gut microbiota. Most reports on this topic show that raw sewage microbiological profiles reflect the human gut microbiota. Human and animal faeces share many commensal microbes as well as pathogens. Faecal-orally transmitted pathogens constitute a serious public health problem that can be minimized through sanitation. Assessing both the sanitation processes and the contribution of sewage to the faecal contamination of water bodies requires knowledge of the content of pathogens in sewage, microbes indicating general faecal contamination and microbes that are only present in human faecal remains, which are known as the human-specific microbial source-tracking (MST) markers. Detection of pathogens would be the ideal option for managing sanitation and determining the microbiological quality of waters contaminated by sewage; but at present, this is neither practical nor feasible in routine testing. Traditionally, faecal indicator bacteria have been used as surrogate indicators of general faecal residues. However, in many water management circumstances, it becomes necessary to detect both the origin of faecal contamination, for which MST is paramount, and live micro-organisms, for which molecular methods are not suitable. The presence and concentrations of pathogens, general faecal indicators and human-specific MST markers most frequently reported in different areas of the world are summarized in this review. 相似文献
109.
To investigate carbon and nitrogen metabolism in Pyropia haitanensis in response to the combined conditions of ocean acidification and diurnal temperature variation, maricultured thalli were tested in acidified culture under different temperature treatments. The results showed a combined effect of ocean acidification and diurnal temperature difference on the C and N metabolism and growth of P. haitanensis. In acidifed culture, algal growth, maximum photosynthetic rate, nitrate reductase (NR) activity, amino acid (AA) content and AA score (AAS) were more significantly enhanced in seaweed under diurnal temperature variation than in seaweed at constant temperature. In acidified seawater, soluble carbohydrates in P. haitanensis increased due to greater dissolved inorganic carbon (DIC), whereas soluble proteins decreased. Under the diurnal temperature treatment, higher temperature during the light period enhanced accumulation of algal photosynthates, whereas lower temperature in the dark period reduced energy consumption, resulting in enhanced algal growth, AA content and AAS. We concluded that suitable diurnal temperature difference would be conducive to C fixation and N assimilation under ocean acidification. However, excessively high temperatures would depress algal photosynthesis and increase energy consumption, thereby exerting a negative effect on algal growth. 相似文献
110.
Shelby A. Flint Dana Olofson Nicholas R. Jordan Ruth G. Shaw 《Restoration Ecology》2019,27(6):1317-1326
Grassland restoration success depends on the development of plant communities that accord with restoration goals. Intraspecific variation in competitiveness may affect community development. For some grassland species, germplasm can be obtained from sources ranging from wild collections to selectively bred cultivars. The extent to which population source affects competitive outcomes in restoration projects is unclear. We addressed this knowledge gap in a glasshouse experiment comparing competitive response and effect among three sources of switchgrass (Panicum virgatum) that are available for restoration: selectively bred cultivars, commercial ecotypes (commercially produced but not deliberately selected), and wild collections. Two strains per source type were grown with four associates chosen to encompass varied functional groups: conspecifics, Bromus inermis, Cirsium arvense, and Solanum ptycanthum. Switchgrass competitive response was evaluated for survival, height, biomass, and shoot:root biomass ratio; competitive effect was assessed as associate survival, height, biomass, and shoot:root ratio. Competitive responses of cultivars and commercial ecotypes were broadly similar, although cultivar biomass exceeded both that of ecotypes and wild collections, and ecotypes had the highest shoot:root ratio. Wild collections were most negatively affected by competition. The shoot:root ratios of all sources were highest when grown with S. ptycanthum, indicating that competitive responses were plastic; plasticity in fitness‐related traits can contribute to persistence in variable environments. Cultivars exerted negative effects on B. inermis. Secondary analyses indicated that all switchgrass sources were most inhibited by the annual S. ptycanthum. To summarize, population source affected multiple aspects of switchgrass competitive ability, when grown against functionally varied associates. 相似文献