Basic terms
sterilization
灭菌
disinfection
消毒
Antisepsis
防腐
Bacteriostasis
抑菌
sterilization
灭菌
The process of destroying
all microbial
forms. A sterile object is one free of all
microbial forms, including bacterial
disinfection
消毒
The reduction or elimination of
pathogenic microorganisms
in or on
materials, so they are no longer a
Antisepsis
防腐
Use of chemical agents on skin or
other living tissue to inhibit or
Bacteriostasis
抑菌
Asepsis
无菌
Controlling Microorganisms By
Physical Agents
High Temperature
Radiation
辐射
Filtration
过滤
High Temperature
Dry heat 干热： protein
oxidation
Hot air sterilization 干烤 Incineration 焚化
red heat 赤热
Moist heat
湿热：
denature proteinsand melt lipids; more effective
Autoclaving: 121121℃℃,103,103.4kPa.4kPa,, 20min20min
cidal for both vegetative organisms and endospores
Boiling water 煮沸灭菌
Pasteurization 巴氏消毒法 : to kill
particular spoilage organisms or pathogens
flash method 瞬间法 : 71.6°C, 15s
fractional sterilization 间歇蒸气灭菌法 :
1) Steam heating to 100 °C for 30 min—— 常压 / 流动蒸气消毒法 Vegetative cells are destroyed but endospores survive
2) Incubate at 30 °C -37 °C overnight Most bacterial endospores germinate
3) Second heat treatment, 100 °C, 30 min Germinated endospores are killed.
4) Second incubation at 30°C-37 °C overnight Remaining endospores germinate
5) Third heat treatment, 100 °C, 60 min
Radiation
Ultraviolet Radiation
microbicidal activity of ultraviolet (UV) light
depends on:
length of exposure
Mechanism:
thymine-thymine dimmers
胸腺
photoreactivation
光复活作用
very poor penetrating power
damage the eyes, cause burns, and cause
Ionizing Radiation
电离辐射
X-rays and gamma rays
more energy and penetrating power than UV
used to sterilize pharmaceuticals and disposable
medical supplies such as syringes, surgical gloves, catheters 导尿管 , and sutures 缝合线
used to retard spoilage in seafoods, meats, poultry,
Filtration
过滤
sterilize
solutions that
may be damaged or
denatured by high
Low Temperature
inhibits microbial growth by slowing down
Desiccation
干燥
has a static effect on microorganisms by
Antimicrobial modes of action for
disinfectants and antiseptics
damage the lipids and/or proteins of the
semipermeable cytoplasmic membrane of
microorganisms resulting in leakage of cellular
materials needed to sustain life
denature microbial enzymes and other proteins
Different categories of such
chemical agents
Phenol and phenol derivatives
alter membrane permeability and denature proteins
chlorhexidine 洗必泰
Soaps and detergents
Anionic (negatively charged) detergents:
mechanically remove microorganisms and other materials but are not very microbicidal.
Cationic (positively charged) detergents: alter
Alcohols
denature membranes
70% solutions of ethyl or isopropyl alcohol 乙醇
或异丙醇
ineffective against endospores and non-enveloped
Acids and alkalies
alter membrane permeability and denature proteins and other molecules
Salts of organic acids: food preservatives
Undecylenic acid 十一烯酸 : dermatophyte 皮肤
Heavy metals
denature proteins
Mercury compounds (mercurochrome 红汞 ,
merthiolate 硫柳汞 ) : bacteriostatic, ineffective against endospores
Silver nitrate 硝酸银 (1%) : put in the eyes of
newborns to prevent gonococcal ophthalmia 淋菌
Chlorine
Iodine and iodophores
denatures microbial proteins
Aldehydes
醛
denature microbial proteins
Formalin 福尔马林 (37% aqueous solution of
formaldehyde gas)
glutaraldehyde 戊二醛 : kill vegetative bacteria in
Factors Influencing Antimicrobial
Activity
The concentration and kind of a chemical agent used; The intensity and nature of a physical agent used;
The length of exposure to the agent;
The temperature at which the agent is used; The number of microorganisms present;
The species or strain of microorganism;
1. 杀灭芽胞最常用和最有效的方法是： ____________ 。 a. 紫外线照射 b. 煮沸 5min c. 巴氏消毒法
d. 流通蒸气灭菌法 e. 高压蒸气灭菌法
2. 灭菌方法错误的是 ____________ 。
a. 手术室空气 - 紫外线
b. 排泄物 - 漂白粉 c. 饮水 - 氯气
d. 含血清培养基 - 高压蒸气灭菌
e. 温度计 -75% 酒精
3. 下述不可能杀灭细菌芽胞的方法是： ____________ 。
a. 煮沸法
b. 巴氏消毒法
c. 间歇灭菌法
d. 干热灭菌法
4. 关于紫外线，说法错误的是 ____________ 。 ( 第 03 章 )
a. 其杀菌作用与波长有关
b. 可损坏细菌的 DNA 构型
c.260-270nm 杀菌作用最强
d. 其穿透力弱，故对人体无损害
e. 紫外线适用空气和物体表面的消毒
5. ____________ 常用于空气或物体表面的消毒。 ( 第 03 章 )
a. 高压蒸气灭菌法 b. 紫外线照射法
c. 滤过除菌法 d. 巴氏消毒法 e. 干烤法 6. ____________ 常用于基础培养基灭菌。 ( 第 03 章 )
a. 高压蒸气灭菌法
b. 紫外线照射法
c. 滤过除菌法
d. 巴氏消毒法
7. 常用于手术器械的灭菌 ____________ 。 a. 高压蒸气灭菌法 b. 紫外线照射法 c. 滤过除菌法 d. 巴氏消毒法 e. 干烤法
8. 常用于血清的除菌 ____________ 。 a. 高压蒸气灭菌法 b. 滤过除菌法
c. 紫外线照射法 d. 巴氏消毒法 e. 干烤法 9. 将牛奶加热 62 30℃ 分钟的目的是 ____________ 。 a. 使牛奶中的蛋白质变性，易于吸收
b. 杀灭牛奶中的所有微生物 c. 杀死牛奶中的病原菌
d. 使牛奶不含活菌
e. 防止或抑制微生物在牛奶中生长和繁殖
