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1、（五）、 食品中常见的微生物 Common foodborne microorganisms in foods,假单胞菌属：革兰氏阴性、极生鞭毛、可运动、不生芽孢、杆状，新鲜食品中的优势菌，常存在于土壤和水中，广泛分布在食品中。另外，许多菌株是嗜冷菌，是导致新鲜冷冻食品腐败的重要细菌。有时腐败能产生水溶性蓝绿色素。 Pseudomonas：These gram-negative rods constitute the largest genus of bacteria that exist in fresh foods. They are typical of soil and water b
2、acteria and are widely distributed among foods .They are , by far, the most important group of bacteria that bring about the spoilage of refrigerated fresh foods since many species and strains are psychrotrophic.Some are notable by their production of water-soluble , blue-green pigments.,产碱杆菌属：革兰氏阴性
3、棒状杆菌，但菌体着色时有时也显现革兰氏阳性反应，周身鞭毛，无芽孢，严格好气，化能有机营养型，大多营养简单。不能发酵糖类，但能产碱（特别是在石芯乳中）。不产色素，分布在各种腐烂物质中，并大量存在于原乳、食用家禽制品以及排泄物中。 Alcaligenes:Although gram negative,these organisms sometimes stain gram positive.They are rods that do not ,as the generic name suggested,N ferment sugars but instead produce alkaline re
4、actions especially in litmus milk. Nonpigmented,they are widely distribu-ted in nature in decomposing matter of all types. Raw milk,poultry product,and fecal matter are common source.,沙雷氏菌属 :革兰氏阴性、杆状、好氧，能分解蛋白质，有时能产生红色素，而不产色素的菌株则比较少见。液化沙雷氏菌是与食物中毒相关的最常见的菌株，能够引起冷冻蔬菜以及肉类制品的腐败。 Serratia： These gram-negat
5、ive rods belong to the family Enerobacteriaceae are aerobic and proteolytic, and they generally produce red pigments on culture media and in certain foods , although nonpigmented strains are not uncommon. S.liquefaciens is the most prevalent of the foodborn species; it causes the spoilage of refrige
6、rated vegetable and meats products.,弧菌属: 革兰氏阴性，直形或弯曲形杆菌，极生鞭毛，兼厌气性，通常需要一定浓度的盐，可污染咸鱼咸肉，有几株菌株能够引起人体肠胃疾病或其他疾病。 Vibrio: They are gram-negative straight or curved rods 。 Several species cause gastroenteritis and other human illness.,志贺氏菌属 : 杆状、不运动、无芽孢、无荚膜、革兰氏阴性，不能利用柠檬酸盐，能产酸但不产气。该属所有菌株都可存在于人体肠道中。 Shigella：
7、All members of this genus are presumed to be enteropathogens.,气单胞菌属：典型的水生革兰氏阴性棒状杆菌，极生鞭毛，兼厌气性。能发酵糖类产生大量气体。通常出现在鱼体中。 Aeromonas: These are typically aquatic gram-negative rods .As the generic name suggest, they produce copious quantities of gas from those sugar fermented.,弯曲杆菌属：革兰氏阴性，弯曲成螺旋杆状，曾归入弧菌属，厌氧或
8、微好氧 。 Campylobacter: These gram negative, spirally curved rods were formerly classified as vibrios. They are microaerophilic to anaerobic.,空肠弯曲杆菌 （Campylobacter) 空肠弯曲杆菌是近年来引起食物中毒最常见的微生物，广泛存在与生肉、生奶和生水中。患腹泻病的宠物也是空肠弯曲杆菌感染的来源 少量的空肠弯曲杆菌可能导致疾病，交叉污染也会致病。食物烹饪过程和牛奶的消毒就能杀灭空肠弯曲杆菌 空肠弯曲杆菌食物中毒的症状包括发热、头痛和感觉不适，紧接着是
9、剧烈腹痛和腹泻，可能出现带血的大便。症状通常持续2-5天，长的可达10天，如有反复可能持续数周 由于空肠弯曲杆菌不耐热，能在一般热处理过程中杀灭。因此，预防弯曲菌病要避免食用未煮透的食品，尤其是乳制品,芽孢杆菌属：革兰氏阳性、杆状，侧生鞭毛能运动，产孢子，抗逆性强，好氧。大部分为中温型，但少部分嗜寒或嗜热。其中两种为病原体：炭疽芽孢杆菌和蜡样芽孢杆菌。但其它种的有些菌株可引起食品中毒。 Bacillus : These are gram-positive sporeforming rods that are aerobes in contrast to the clostridia, whic
10、h are anaerobes.Although most are mesophiles, psychrotrophs and thermophiles exist.The genus contains only two pathogens:B. anthracis and B.cereus. Although most strains of the latter are nonpathogens,some cause foodborne gastroenteritis.,枯草芽孢杆菌 芽孢杆菌，菌落变化大 G (+) 用途：蛋白酶、-淀粉酶、5核苷酸酶、氨基酸、核苷等 如：BF7658 生产
11、-淀粉酶 AS1.398 中性蛋白酶,梭状芽孢杆菌属：杆状，革兰氏阳性，形成的卵圆形芽孢使母细胞膨胀成梭状，厌气性。能分解糖产生多种有机酸、并产气，有的能产生毒素。 该属包括许多菌株，有些会引起人体疾病。中温型，嗜冷型，嗜热型菌株都存在。 Clostridium: These are anaerobic spore-forming rods.The genus contains many species, some of which cause disease in humans . Mesotrophic, psychrotrophic , and thermophilic strains
12、exist.,类芽孢杆菌属: 这个新建立的属主要包括以前属于芽孢杆菌属以及梭状芽孢杆菌的菌株。 Paenibacillus: This newly established genus is comprised of organisms formerly in the genera Bacillus and Clostridium. 莫拉氏菌属：革兰氏阴性短杆菌。它们的新陈代谢是氧化性的，同时葡萄糖发酵过程中不产酸。 Moraxella: They are short gram-negative rods . Their metabolism is oxidative,and they do n
13、ot form acid from glucose.,索丝菌属：革兰氏阳性、杆状，不产芽孢。对数期的细胞为棒杆状，而衰老后则为球状。通常存在于肉类以及冷藏温度下保存的肉类制品中。 Brochothrix:These are gram-positive nonsporeforming rods.Typically, exponential-phase cells aer rods, and older cells are coccoids, a feature typical of coryne-forms. They are common on processed meats and on f
14、resh and on fresh and processed meats that are stored in gas-impermeable packages at refrigerator tempera-tures.,柠檬酸杆菌属：革兰氏阴性、杆状、周生鞭毛，无芽孢，兼厌气性，能产酸、产气。所有菌株都能利用柠檬酸盐为惟一碳源生长，能存在于肠道中进行缓慢的乳糖发酵，有的种能引起食品腐败和人的肠胃炎。 Citrobacter: These enteric bacteria are slow lactose-fermenting , gram-negative rods. All membe
15、rs can use citrate as the sole carbon source.,肉杆菌属：革兰氏阳性、杆状，过氧化氢酶阴性。异型发酵，绝大多数能在045 。C生长。有些种能发酵葡萄糖产生气体。它们与乳酸杆菌的区别在于不能在醋酸盐培养基上生长，在代谢过程中能够合成油酸。通常存在于真空包装的肉制品或相关制品中。 Carnobacerium: These are gram-positive , catalase-negative rods. They are heterofermentative , and most grow at 0 。C and none 45 。C . Gas i
16、s produced from glucose by some species. They differ from the lactobacilli in being unable to grow on acetate medium and in their synthesis of oleic acid. They are found on vacuum-packaged meats and related products.,棒杆菌属：棒杆状，革兰氏阳性，与部分蔬菜以及肉类制 品的腐败有关。是重要的嗜冷菌，但大多数菌株都是中温型。其中白喉棒杆菌能够引起人体白喉病。 Corynebacterium : This is one of the true coryneform genera of gram-positive, rod-shaped bacteria that are sometimes involved in the spoilage of vegetable and meat products.Most are mesotrophs,
