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MindMap Gallery 2 Microbial groups and common food microorganisms
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2 Microbial groups and common food microorganisms
Food microorganisms, summarizes the taxonomic units of microorganisms, common fungi, prokaryotic microorganisms, bacteria, non-cellular organisms, viruses, etc. in food.
Edited at 2024-01-20 17:11:03
- cáncer de pulmón
El cáncer de pulmón es un tumor maligno que se origina en la mucosa bronquial o las glándulas de los pulmones. Es uno de los tumores malignos con mayor morbilidad y mortalidad y mayor amenaza para la salud y la vida humana.
- diabetes
La diabetes es una enfermedad crónica con hiperglucemia como signo principal. Es causada principalmente por una disminución en la secreción de insulina causada por una disfunción de las células de los islotes pancreáticos, o porque el cuerpo es insensible a la acción de la insulina (es decir, resistencia a la insulina), o ambas cosas. la glucosa en la sangre es ineficaz para ser utilizada y almacenada.
- sistema digestivo
El sistema digestivo es uno de los nueve sistemas principales del cuerpo humano y es el principal responsable de la ingesta, digestión, absorción y excreción de los alimentos. Consta de dos partes principales: el tracto digestivo y las glándulas digestivas.
2 Microbial groups and common food microorganisms
- cáncer de pulmón
El cáncer de pulmón es un tumor maligno que se origina en la mucosa bronquial o las glándulas de los pulmones. Es uno de los tumores malignos con mayor morbilidad y mortalidad y mayor amenaza para la salud y la vida humana.
- diabetes
La diabetes es una enfermedad crónica con hiperglucemia como signo principal. Es causada principalmente por una disminución en la secreción de insulina causada por una disfunción de las células de los islotes pancreáticos, o porque el cuerpo es insensible a la acción de la insulina (es decir, resistencia a la insulina), o ambas cosas. la glucosa en la sangre es ineficaz para ser utilizada y almacenada.
- sistema digestivo
El sistema digestivo es uno de los nueve sistemas principales del cuerpo humano y es el principal responsable de la ingesta, digestión, absorción y excreción de los alimentos. Consta de dos partes principales: el tracto digestivo y las glándulas digestivas.
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- Outline
Microbial groups and common food microorganisms
taxonomic unit of microorganisms
taxonomic unit of microorganisms
microbial nomenclature
Nomenclature of relevant laws formulated by the International Committee on Classification of Microorganisms
binomial method
Microbial classification basis and methods
Morphological characteristics: individual body, colony morphology
Physiological characteristics and biochemical reactions: types of nutrients, utilization of carbon and nitrogen sources, metabolites, and the relationship between temperature and oxygen, etc.
Ecology: parasitism, symbiosis
cell wall components
Nucleic acid analysis: GC content, DNA hybridization, nucleic acid sequence, etc.
Numerical Analysis
Bacterial Classification System: Berger's Manual of Identification Bacteriology, Widely used and representative
prokaryotic microorganisms bacteria
The shape, size and arrangement of bacteria
cocci
Spherical or nearly spherical, according to the division surface and arrangement, it can be divided into monococci, diplococci, tetradococci, Sarcina, staphylococci, and streptococci.
bacilli
Single bacilli, paired bibacilli, chain streptobacteria
Spiral bacteria
Generally 5 to 50 microns × 0.5 to five microns
Vibrio
The spiral is less than one ring, banana-shaped or comma-shaped, Vibrio cholerae
spirillum
2 to 6 rings, Microspirillum
spirochetes
A spiral-shaped bacterium with many rotations and a long, soft body, such as Treponema pallidum
minority form
Triangular, filamentous, disc-shaped
structure of bacteria
basic structure
cell wall (degree of peptidoglycan cross-linking, Gram-positive and Gram-negative bacteria)
Extracellular, protective structure composed of polysaccharides on the surface
Tough and elastic, maintaining the inherent shape of the bacteria
Protect bacteria against hypotonic environment
Exchange of substances inside and outside the cell
There are a variety of antigen structures that stimulate the body to produce an immune response
Related to drug lysozyme sensitivity
related to bacterial pathogenicity
Relevant to Gram staining properties of bacteria
Gram stain
Gram-positive bacterial cell wall
There are about forty layers of peptidoglycan. Glycan backbone➕tetrapeptide side chain➕pentapeptide cross-link bridge
Gram-negative bacterial cell wall
Peptidoglycan layer (several layers) ➕Outer membrane (glycan backbone➕tetrapeptide side chain➕peptide bridge)
cell membrane
An elastic, semipermeable membrane composed of a phospholipid bilayer and protein-encrusted proteins
Accounting for about 10% of the dry weight of cells, it contains 60% to 70% protein, 20% to 30% lipids and a small amount of polysaccharides. The lipids are phospholipids.
The film thickness is 8 to 10 nanometers, and the outside is close to the cell wall
Bacterial cell membranes contain a rich enzyme system that performs metabolic functions
Metabolic synthesis mediator
Separate, form cells and organelles, and provide a relatively stable internal environment for life activities
Barrier effect, water-soluble substances on both sides of the membrane cannot pass freely
Selective transport of matter, accompanied by transfer of energy
Biological functions include enzymatic reactions, cell recognition, electron transfer, etc.
Material transport function is the exchange of materials between cells and the environment
cytoplasm
Contains various particles
Nucleoplasm (without nuclear membrane)
The nuclear region is a circular double-stranded DNA filamentous structure without a nuclear membrane. It is also called a nucleoid, nucleoplast or nuclear genome.
The nuclear region carries most of the genetic information of the bacterium
Plasmids are mobile circular DNA fragments
autonomous replication
incompatibility
Metastasis (transmission between cells)
Encode certain proteins with special functions
special
capsule
Invasiveness
flagellum (Motor organ, light-tending, benefit-tending, birth position)
Pathogenicity and antigenicity
Thin filaments that grow from a base point on the membrane and pass through the cell wall and mucus layer. They are about 150 microns long, ranging from one to two to hundreds.
There are various modes of insertion, including uni-terminal flagellates, telopheles, bi-terminal flagellates and peritrichous flagellates.
Flagellar movement mode, swimming in liquid, gliding on solid surface, rotating and shuttle in liquid
Most cocci have no flagella, some bacilli have flagella, and all spiral bacteria have flagella.
pili
adhere to host
spores (Low water content, dense, resistant to adverse environment)
bacterial dormant state
Some bacteria, mostly bacilli, form a highly stress-resistant spherical or oval dormant body that has no reproductive function under certain conditions. The cytoplasm is highly concentrated and dehydrated.
It adapts to harsh environments and can resist drying, high heat, high acid and alkali, and high osmotic environments. It is in a dormant state under harsh conditions, and the conditions are suitable for germination and growth.
Clostridium tetani survives in boiling water for 3 hours
Heat resistance: Dense spore wall, low water content, containing 2,6-pyridinedicarboxylic acid (DPA) in the form of calcium salt
reproduction of bacteria
Use your own genetic material, intracellular energy, organelles, etc. to complete reproduction
binary splitting method
Bacterial colony morphology
Colonies are mononuclear cells that grow and reproduce on or within a suitable solid medium, forming a population of daughter cells with a certain shape that is visible to the naked eye.
Colony characteristics include size, shape, edges, gloss, texture, transparency, color and surface condition, etc.
Common bacteria in food
Gram-negative bacteria
Pseudomonas
Biological characteristics: straight or slightly curved, no spores, polar flagella, motile, obligately aerobic, requires an optimal pH of 5 to 9.5, a growth temperature of 4 to 42 degrees Celsius, partially psychrophilic, simple nutritional needs, decomposable Fat and protein have strong ability to reproduce quickly
The environment is widely distributed. Typical soil and aquatic bacteria can contaminate food. Their oxidation products and mucus can cause food spoilage, odor and discoloration.
Common bacteria, at least 29 species are opportunistic pathogens
Pseudomonas aeruginosa
Water-soluble pyocyanin and fluorescein can be detected in water and soil
Bottled water hygiene indicator bacteria (WHO)
purulent infection
Often B hemolysis
pyocyanin, fluorescein
Blue-green, yellow-green
Pseudomonas fluorescens
Contamination of water, meat, and blood products
Fluorescein
yellow-green
Pseudomonas putida
Fish pathogenic bacteria
Fluorescein
yellow-green
Pseudomonas putrefaction
milk eggs
Pseudomonas stephensi
Unnamed yellow pigment
yellow
Pseudomonas alcaligenes
Unnamed yellow pigment
yellow
Alcaligenes
Distributed in water, soil, feed and human and animal intestines, milk and poultry products, rotten matter, produces mucus, does not ferment sugar, but produces alkali, litmus milk analysis
Flavobacterium
Can grow at low temperatures and produce fat-soluble pigments
Strong ability to decompose protein and low effect on carbohydrates
Rotten milk, fish, meat, eggs, etc.
Salmonella spp.
Straight rod-shaped, peritrichous flagella, aerobic, most colonies are opaque
Medium temperature, pH 5~9, less than 4% NaCL growth
Water-insoluble yellow, purple and red pigments
Includes nine species
Salmonella liquefied
food poisoning
Salmonella marcescens
Aerobic, 20 degrees Celsius, water and soil, nosocomial infection
prodigiosin
Anti-cancer and anti-microbial
Achromobacter
Water and soil decompose sugar to produce acid, causing meat and seafood to deteriorate and become sticky.
Escherichia
Proteus
Acetobacter
Salmonella
Shigella
Erwinia
Gram-positive bacteria
Bacillus
Biological characteristics: cells are straight rod-shaped, arranged in pairs or chains, with terminal or periphyllous flagella, and can produce spores
Distributed in soil and water
eight species
Bacillus cereus
carbohydrate
Bacillus subtilis
Bread spoiled
Production of protease, natto, and engineering bacteria
Bacillus anthracis
Zoonoses
Clostridium spp.
Anaerobic or microaerophilic, decomposes sugar to produce acid and gas
Canned food spoilage: Clostridium botulinum, Clostridium pyrolytica
Obligately anaerobic, spores are oval, terminal, optimal growth temperature is 55 degrees Celsius, weak growth is between 37 and 45 degrees Celsius, thermophilic anaerobic bacteria
Lactobacillus
Various forms, mainly rod-shaped, single or chain-shaped bacteria, non-motile, anaerobic or microaerophilic, fermenting sugar to produce lactic acid, optimal temperature 45 degrees Celsius, colonies round, white
Common bacteria
Lactobacillus bulgaricus
Lactobacillus lactis
Distributed in grains, vegetables, fermented bread, wine, dairy products
Usage: Lactic acid and calcium lactate, sauerkraut and kimchi, work with other microorganisms to form the flavor of wine and soy sauce, antibacterial peptides
Leuconostoc
Round or oval, arranged in chains, often found on milk, vegetables, and fruits
Economic Value
Synthesize large amounts of glucan and produce dextran
harm
Milk becomes sticky
Sugar industry increases sugar liquid viscosity
Staphylococcus
Micrococcus
Lactococcus
Corynebacterium
non-cellular organisms, viruses
A type of non-cellular microorganism that is smaller than bacteria, can pass through bacterial filters, contains only one kind of nucleic acid, and proliferates in living cells
Basic characteristics: only one kind of nucleic acid, tiny
structure
Nucleocapsid, nucleic acid and protein shell; some are composed of cysts, fat or protein
Capsid structure: helical symmetry, icosahedron, compound symmetry
Classification: Baltimore Classification
double stranded DNA virus
Viruses with double-stranded DNA as genetic material: adenovirus, herpesvirus, poxvirus, etc. Poxviridae Orthopoxvirus genus variola virus, monkeypox virus, vaccinia virus and cowpox virus
single-stranded DNA virus
Representative viruses: parvovirus, etc.
double-stranded RNA virus
Rotavirus, reovirus, etc.
positive-sense single-stranded RNA virus
New coronavirus, norovirus, hepatitis C, hepatitis A virus, dengue fever, etc.
Antisense single-stranded RNA virus
Influenza virus, rabies virus
single-stranded RNA retrovirus
HIV virus etc.
double-stranded DNA retrovirus
Hepatitis B virus, etc.
Virus life cycle
Viral particles replicate after invading cells, undergo translation and packaging, and are released from cells after maturation.
Phage
Microbial viruses that infect bacteria
Life cycle: adsorption, invasion, replication, assembly, release
Lysogenic and potent
Common fungi in food
Fungi Overview
Fungi have true nuclei
Heterotrophic organisms that do not have chlorophyll and rely on absorption for nutrition
Generally, spores can be produced through asexual reproduction and sexual reproduction to continue the population.
Its typical vegetative body is a filamentous molecular structure
The main component of the cell wall is chitin or cellulose
Including single-cell fungi (yeast), filamentous fungi (molds), large fruiting body fungi (bacteria)
Fungal vegetative body: a bacterial cell that grows and absorbs water and nutrients to proliferate.
Protoplasm, pseudohyphae, single cell, two-type hyphae, mycelium
The structure and function of fungi
cell wall
Polysaccharide chains, chitin, cellulose
cell membrane
cell nucleus
Nuclear membrane, nucleolus, chromosomes
cytoplasm
organelles
Mitochondria, ribosomes. . .
yeast
A general term for unicellular non-filamentous fungi
Asexual (budding and fissioning) and sexual reproduction are possible
Mainly belong to Ascomycetes and Deuteromycetes
Ascomycetes can reproduce sexually
Ascospores
Deuterofungi cannot reproduce sexually
Colonies are similar to bacteria, large and thick, usually milky white, a few are colored
Saccharomyces
Spherical, ellipsoidal or sausage-shaped, with multiple lateral buds or ascospores
Can form pseudohyphae
Strong fermentation power, produces ethanol and carbon dioxide, does not ferment lactose
beer yeast
Used in beer, liquor, fruit wine, bread
Distributed in fruit peels, fermented juices, soil
Physiological characteristics: Optimum temperature 25～26 degrees Celsius
Wort slab: milky white, glossy, smooth, with neat edges
budding reproduction
Ferment glucose, sucrose, maltose, etc., not lactose
grape juice yeast
whisky
Saccharomyces roudii
Making soy sauce and sweet sauce
honey yeast
High sugar food spoilage
Resistant to high salt, soy sauce gray-white powdery film
Candida
Spherical, oval or elongated
Polygonal budding can form pseudohyphae, some have fungal threads, and also form chlamydospores.
Ethanol fermentation capacity
Applied to alcoholic fermentation, single cell protein
Common species
Candida priogenum
Producing edible protein from industrial waste
Candida lipolytica
Petroleum dewaxing
Candida tropicalis
single cell protein, feed protein
Opportunistic pathogens
Rhodotorula
No alcoholic fermentation ability
Contaminated food, meat and pickles, with red spots
Shower curtains and other wet furniture
Widely distributed in the environment and food
red yeast
application
Produces pigments, lycopene, carotenoids
microbial lipids
Fat content accounts for 20 to 69% of dry matter
Composition is similar to vegetable oil
Whole cell biocatalyst
Rhodotorula acid, postharvest biological control of fruits
Animal feeding, reducing resistance, improving survival of cubs
Torulopsis sphaeroides
Tolerant to high salt and sugar, juice condensed milk
Condensed Milk Toroidula
Condensed milk cans produce gas, expand, and even burst.
Frozen food, dairy products, fish and shellfish spoilage
Production of glycerol, feed yeast
Mold
Common name for filamentous fungi
Wide distribution and many types
Powerful decomposition and synthesis capabilities
brewed food
Enzyme
Mildew
Hyphal morphology
According to the presence or absence of septa, they are divided into septate hyphae (such as Rhizopus and Mucor) and septate hyphae (Penicillium and Aspergillus).
Classification by function: basal hyphae or vegetative hyphae, aerial hyphae, reproductive hyphae
specialized structure
Creeping hyphae and rhizoids: have an extension function parallel to the surface of the solid substrate. Rhizomes (extending into the substrate) and cyst stalks grow on them, and new creeping hyphae continue to extend to form bacterial lawns. Rhizopus and Plowshare species are common
Sclerotium: a hard dormant body composed of hyphae groups. When conditions are suitable, spore stalks, hyphae, fruiting bodies, etc. can be produced.
Mold reproduction and spore types
Spores are reproductive cells that can directly or indirectly develop into new individuals after being separated from their parents.
Asexual reproduction: arthrospores, zoospores, metaspores, cystospores, conidia
Sexual reproduction: oospores, zygospores, ascospores, basidiospores
Rhizopus
Morphological characteristics: colonies are flocculent, white hyphae, unseptate multinucleated, rhizoids and creeping hyphae. The rhizoids give rise to cystic stalks to form cystospores.
Polluting bacteria distributed in soil and air laboratories
Contaminated food: starchy food rotten Usage: amylase preparation for wine making
Rhizopus black, Rhizopus oryzae, Rhizopus sinensis
Mucor
Colonies are gray-white or brown cotton-like
The hyphae are well developed and dense, with no septa and multiple nuclei, no rhizoids, and no creeping hyphae.
Asexual reproduction is cystospores, which are distributed in fruits and vegetables, starchy foods, and grain mold.
Mucor racemosa, Mucor tall, Mucor micro
application
Produce protease and make bean curd and tempeh
Amylase-producing, saccharifying bacteria or amylase-producing
Produce citric acid, lactic acid, glycerin, etc.
Aspergillus
The hyphae are well-developed, multi-branched, septate and multi-nucleated.
Colonies are multi-colored and mycelial spores are of different colors
Conidiophores grow on the podocytes, and the beaded conidia heads are shaped like chrysanthemums and come in various colors.
Distributed in soil, air, grains, food, clothing, leather, etc. moldy and rotten
Some can produce toxins
application
Sauce making, wine making and vinegar making
Production of enzyme preparations
Produce organic acids
Bacteria for producing saccharified feed
Monascus
Monascus red, purple, orange
Function
pigment
Cholesterol-lowering active substance-monacrine K
hypotensive
Produces enzymes, amylase, glucoamylase, pectinase
Esters-producing strong-flavor wine
Antioxidant, weight loss, tumor inhibition
Antibacterial activity - Staphylococcus aureus, Pseudomonas aeruginosa
Penicillium
The colonies are diverse and multi-colored, the hyphae are septate and multinucleated, and there are no podocytes.
The spores have a unique broom-like structure
Distribution of soil, air, decaying organic matter and food
Disease related, Penicillium chrysogenum, Penicillium citrinum, Penicillium chrysogenum
Industrial bacteria, antibiotics, organic acids