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  • Prokaryotes人类用途 -- -- 高级

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    What is aromatic black pu-erh tea?
    ::什么是芳香黑色茶?

    Aromatic black pu-erh tea is from the Yunnan Province in China. Leaves undergoes double bacterial and fungal and are compressed into different forms. Pu-erh tea is used for improving mental alertness and sharp thinking. It is also used for reducing high cholesterol.
    ::中国云南省的芳香黑黑茶,双菌和真菌叶,压缩成不同形式,用茶提高精神戒备和思维敏锐,用它来减少高胆固醇。

    Human Uses of Bacteria
    ::人类使用细菌a

    can be used by humans in a number of useful ways. Despite the fact that some bacteria play harmful roles, such as causing diseases and spoiling food , the industrial and economic importance of bacteria includes both their useful and harmful aspects. Examples of the role of bacteria in industry include the following:
    ::尽管某些细菌起着有害的作用,例如造成疾病和破坏食物,但细菌的工业和经济重要性包括它们的有用和有害方面。

    • Fermentation processes, such as brewing, baking, and cheese and butter manufacturing.
      ::发酵过程,如酿酒、烘烤、奶酪和黄油制造。
    • Chemical manufacturing, such as the production of ethanol, acetone, organic acids, , and perfumes.
      ::化学制造,如乙醇、丙酮、有机酸和香水的生产。
    • Pharmaceuticals, such as the manufacture of antibiotics , vaccines , and steroids.
      ::药品,如抗生素、疫苗和类固醇的制造。
    • Energy , in the form of biogas (methane).
      ::以沼气(甲烷)为形式的能源。
    • Food products, such as beverages, dairy products, amino acids , , and nutritional supplements.
      ::食品,如饮料、奶制品、氨基酸、营养补充剂。
    • Decomposing sewage waste.
      ::排污废物分解。
    • , such as composting processes and use as pesticides.
      ::,例如堆肥工艺和用作农药。

    Food
    ::食品食品食品

    Bacteria, often Lactobacillus, along with yeasts and molds, have been used for thousands of years to make fermented foods such as cheese, pickles, soy sauce, sauerkraut, vinegar, wine, beer, and yogurt (some of which are shown in  Figure  . ) Bacteria are also used in the processing of coffee and cocoa beans but are not found in the end-products (coffee and chocolate). Lactobacillus bacteria also live in the intestines of humans and , where their growth inhibits the growth of potentially pathogenic bacteria. These beneficial bacteria are therefore sold as probiotic dietary supplements, such as “live” yogurts.
    ::细菌,经常是细菌,与酵母和霉菌一起,几千年来一直被用来制造发酵食品,如奶酪、泡菜、黄油酱、酸菜、醋、葡萄酒、啤酒和酸奶(其中一些见图......)。 细菌也用于加工咖啡和可可豆,但最终产品(咖啡和巧克力)中找不到。 细菌也存在于人类肠中,其生长抑制了潜在病原细菌的生长。 因此,这些有益的细菌作为“活的”酸奶等代生食物补充品出售,如“活的”酸奶。

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    Various lactic acid bacteria, including Leuconostoc, Lactobacillus, and Pediococcus, are used to ferment sauerkraut (center left, with sausage). Fermented dairy products, such as cheese (center right) and yogurt (right), are made by lactic acid bacteria that digest the milk sugar, lactose. The distinctive flavors of these foods result from the lactic acid that forms when bacteria ferment the sugars in the vegetables and milk.

    Pollution Clean-Up
    ::清理污染

    Some organisms are able to break down compounds such as petroleum or pesticides, which makes them useful in mining, pollution clean-up, and waste processing. Bioremediation is any process that uses microorganisms, , green plants, or their enzymes to clean a contaminant from the environment. Bacteria that can digest the hydrocarbons in petroleum (oil) can be used to clean up oil spills. After the Exxon Valdez oil spill in 1989, fertilizer was added to some of the beaches in Prince William Sound in Alaska, where the accident took place, in order to increase the growth of these naturally occurring bacteria. 
    ::一些生物体能够分解石油或杀虫剂等化合物,使其在采矿、污染清理和废物处理方面有用;生物补救是利用微生物、绿色植物或其酶清理环境污染物的任何过程;可以吸收石油(石油)中碳氢化合物的细菌可用于清除石油溢漏;1989年埃克森·巴尔德斯漏油事件后,在阿拉斯加威廉王子湾的一些海滩上添加化肥,以便增加这些自然产生的细菌的生长量。

    Bacteria are also used for the bioremediation of industrial toxic wastes, such as mercury. Certain bacteria can digest that are toxic to humans and other animals, such as polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and pesticides.
    ::细菌还被用于对工业有毒废物(如汞)进行生物补救,某些细菌可以消化对人类和其他动物有毒的细菌,如多氯联苯、多环芳烃和杀虫剂。

    Microbial Miners
    ::微生物矿工

    Biomining is the use of to extract certain minerals from ores. Using a bacterium such as Thiobacillus ferooxidans to leach copper from mining leftovers has improved recovery rates and reduced operating costs for mining companies. Also, using microorganisms to leach out the minerals, instead of the traditional methods of high heat or toxic chemicals, is better for the environment.
    ::生物开采是利用矿石开采某些矿物,利用Thiobacillus ferrooxidans等细菌从采矿剩余矿渣中沥滤铜,提高了回收率,降低了采矿公司的经营成本,而且,利用微生物浸出矿物,而不是传统的高热或有毒化学品方法,对于环境来说更好。

    Waste Disposal and Biogas Production
    ::废物处理和沼气生产

    Aerobic and anaerobic bacteria are used to decompose sewage waste. They break down organic matter into harmless, soluble sludge in settling tanks. The methane gas produced is used as an energy source. Figure shows aerobic digestion of sewage. The wastewater is mixed up, or agitated, which keeps the oxygenated, allowing aerobic bacteria in the water to break down the waste matter.
    ::有氧和厌氧细菌被用来分解污水废物,将有机物分解成无害、可溶解的沉淀池污泥,产生的甲烷气用作能源,图中显示了污水的有氧消化,废水混合或搅拌,保持氧,使水中的有氧细菌分解废物。

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    Pumping air through sewage gives oxygen to the bacteria that break down the organic molecules in the waste.

    When organic matter is broken down anaerobically, methane gas is produced. Methane gas that is released from landfills and sewage treatment plants can be collected and used as fuel to produce electricity, heat buildings and water, or power vehicles, like the bus in  Figure . When used as a fuel, methane is often called biogas. Biogas can also be made in special equipment called anaerobic digesters, where waste is broken down in the absence of oxygen. A biogas plant can be fed with crops, such as maize silage, or biodegradable wastes, including sewage sludge and food waste.
    ::当有机物质被厌氧地分解时,就会产生甲烷气,填埋场和污水处理厂释放的甲烷气可以收集和用作燃料,生产电、热建筑和水,或像图中的公共汽车那样的动力车辆,甲烷通常被称为沼气,沼气也可以在称为厌氧消化器的特殊设备中制造,在缺乏氧气的情况下将废物分解,沼气厂可以种植作物,如玉米淤泥,或生物降解废物,包括污水污泥和食物废物。

    Biogas as fuel for vehicles. The bus is powered by methane gas
    Biogas as fuel for vehicles. The bus is powered by methane gas

    Agricultural Uses
    ::农业使用

    Heterotrophic microbes are very common in nature and are responsible for the breakdown of large organic molecules which are generally indigestible to larger animals. They also return nutrients to the soil , such as the nutrients that are locked up in the dead leaves in  Figure . Prokaryotes and other microorganisms also have important roles in biogeochemical cycles , the cycles that move molecules and nutrients through the biotic and abiotic parts of the environment. Examples include the nitrogen, carbon, and phosphorus cycles. To learn more about biogeochemical cycles, see the Recycling Matter concepts in Concept Ecology (Advanced).
    ::遗传营养性微生物在性质上非常常见,造成大有机分子的分解,这些分子一般是大动物所无法开发的,它们还把养分还给土壤,如图中死叶中封闭的养分。Prokaryotes和其他微生物在生物地球化学循环、分子和养分通过环境的生物和非生物部分的循环中也起着重要作用。例子包括氮、碳和磷循环。要更多地了解生物地球化学循环,请参见概念生态学中的回收物质概念(高级)。

    These fallen leaves will be broken down by decomposing bacteria in the soil. Decomposition returns the nutrients in the leaves to the soil, where they can be used by other organisms. The aerobic breakdown of biodegradable organic matter, such as leaves, fruits, vegetables, grass clippings, and even animal materials, by microorganisms is called composting. The anaerobic breakdown of animal tissues by microorganisms is called putrefaction.
    These fallen leaves will be broken down by decomposing bacteria in the soil. Decomposition returns the nutrients in the leaves to the soil, where they can be used by other organisms. The aerobic breakdown of biodegradable organic matter, such as leaves, fruits, vegetables, grass clippings, and even animal materials, by microorganisms is called composting. The anaerobic breakdown of animal tissues by microorganisms is called putrefaction.

    Nutrient Recycling
    ::营养再循环

    Bacteria and other microorganisms that are able to digest complex molecules, such as lignin and cellulose , are important in composting. Lignin and cellulose are components of plant cell walls . Composting is the aerobic process of breaking down (decomposing) organic materials into simpler molecules to return nutrients to the soil. Composting is often used in organic gardening and farming. Nitrogen fixing bacteria are also used to increase the nitrogen content of soil. This is done by planting legumes, such as beans or clovers, and allowing the bacteria in their to fix nitrogen into the soil for some time. The legumes and their resident bacteria are then tilled into the soil so that other crops can be planted.
    ::细菌和能够消化复杂分子的其他微生物,如核素和纤维素,在堆肥中很重要。Lignin和纤维素是植物细胞壁的组成部分。合成是将有机材料分解(分解)为更简单的分子以将营养物还给土壤的有氧过程。合成经常用于有机园艺和耕作。氮固化细菌也用来增加土壤的氮含量。这通过种植豆类或三叶素等豆类和来完成,并允许细菌在一段时间内将氮固入土壤中。然后,将豆类及其常住细菌耕种到土壤中,以便种植其他作物。

    Pest Control
    ::害虫控制

    Bacteria can also be used in the place of pesticides. Bacillus thuringiensis are Gram-positive, soil-dwelling bacteria that are used to control certain plant pests. B. thuringiensis produces an endotoxin (called Bt toxin) that is toxic to mosquitoes, moths, and certain caterpillars. Because of its limited toxicity to certain , Bt toxin is regarded as environmentally friendly. It does not affect humans, wildlife, pollinators , and most other beneficial insects, such as ladybugs and bees. Bt toxin has been genetically engineered into crops (see Concept (Advanced)).
    ::细菌也可以用来代替杀虫剂。丁二烯菌是用于控制某些植物害虫的Gram-阳性、土壤栖息细菌。B. 丁二烯生出一种对蚊子、蛾子和某些毛虫有毒的内分泌毒素(称为Bt毒素),Bt毒素由于对某些虫子的毒性有限,被认为对环境无害。它不会影响人类、野生生物、授粉者和其他大多数有益的昆虫,如虫和蜜蜂。Bt毒素已被基因改造成作物(见“概念”(Advanced))。

    Summary
    ::摘要

    • Bacteria are used in fermentation processes, such as brewing, baking, and cheese and butter manufacturing. They are also used in agriculture, such as in composting processes and as pesticides. Bacteria play the key role in nitrogen fixation.
      ::细菌用于发酵过程,如酿造、烘烤、奶酪和黄油制造,细菌也用于农业,如堆肥过程和杀虫剂,细菌在固氮中起着关键作用。

    Review
    ::回顾

    1. Identify two industrial and two agricultural uses of bacteria.
      ::查明细菌的两种工业用途和两种农业用途。