《食品微生物学》课程教学资源（PPT课件讲稿）微生物生态与生态工程

Chapter 8 microbial ecology and ecological engineering

Chapter 8 microbial ecology and ecological engineering

Microbial ecology is a science designed to study the interaction between microbes and the environment which is consisted of two parts--biosurrounding and non-bio surrounding Microflora or normal flora(微生物区系或正常菌 群)

Microbial ecology is a science designed to study the interaction between and the environment which is consisted of two parts——biosurrounding and non-bio surrounding . microbes Microflora or normal flora（微生物区系或正常菌 群）

Ecosystem is a system formed by the living creatures in a certain sphere and their closely related non biological surroundings. In the system, the material and the energy is constantly circulated between the creatures and between the creatures and the environment thus form a self-sustainable, relatively stable and independent integrated system

Ecosystem is a system formed by the living creatures in a certain sphere and their closely related non￾biological surroundings. In the system, the material and the energy is constantly circulated between the creatures and between the creatures and the environment, thus form a self-sustainable, relatively stable and independent integrated system

10 levels in the biological research Biosphere(生物圈) Individual Ecosystem(生态系统) Organ Community(群落) Tissue Population(种群)ce‖ Organelle molecule Research range of ecology

10 levels in the biological research ◼ Biosphere（生物圈） ◼ Ecosystem（生态系统） ◼ Community（群落） ◼ Population（种群） ◼ Individual ◼ Organ ◼ Tissue ◼ Cell ◼ Organelle ◼ molecule Research range of ecology

biosphere Hydrosphere Lithosphere atmosphere

biosphere ◼ Hydrosphere ◼ Lithosphere ◼ atmosphere

Aquatic ecosystem Producer--cyanobacteria and algae Consumer-human and animals Decomposer--bacteria and plankton (浮游生物)

Aquatic ecosystem ◼ Producer——cyanobacteria and algae ◼ Consumer——human and animals ◼ Decomposer——bacteria and plankton （浮游生物）

Microbial microenvironment(微生 物的微环境) is the environment where the microbes living. There are numberless microbial microenvironment on the earth and every microenvironment itself is heterologous due to the rapid physical and chemical changes resulted from the different time and spaces

Microbial microenvironment （微生 物的微环境）is the environment where the microbes living.There are numberless microbial microenvironment on the earth， and every microenvironment itself is heterologous due to the rapid physical and chemical changes resulted from the different time and spaces

Environmental gradients(环境梯度) As far as food is concerned a practical example is when a dilute syrup is added to the surface of a cup of dense syrup, facultative osmo philic microbes (兼性嗜渗微生物) will select the upper layer of dilute syrup to live in and the obligate osmophiles would choose the bottom layer to live in

Environmental gradients(环境梯度) As far as food is concerned, a practical example is when a dilute syrup is added to the surface of a cup of dense syrup, facultative osmo philic microbes (兼性嗜渗微生物)will select the upper layer of dilute syrup to live in and the obligate osmophiles would choose the bottom layer to live in

Limits of tolerance(耐受限度) a The range of a certain ecological factor from the maximun to the minimum that the microbe can Withstand for example, the ph limited for the mould is 1.510

Limits of tolerance (耐受限度) ◼ The range of a certain ecological factor from the maximun to the minimum that the microbe can withstand ◼ for example, the pH limited for the mould is 1.5~10

Food as a special microbial ecosystem Heterologous Surface environment biofilm and nata(纳塔) Nutritional provision Biomass and growth rate Population relationships community succession

Food as a special microbial ecosystem ◼ Heterologous ◼ Surface environment , biofilm and nata (纳塔) ◼ Nutritional provision ◼ Biomass and growth rate ◼ Population relationships community succession