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Cell Lysis and Disruption
Cell disruption
Laboratory techniques: SonicationEnzyme treatment
Industrial technology: Ball mill grinding
Homogenization (orifice type)
High mechanical shear
Heat generation
*Chemical method + mechanical method combination
Product of Interest: Intracellular or Extracellular ?
Method Technique PrincipleStress
on ProductCost Examples
Chemical Osmotic Shock Osmotic rupture of membrane
Gentle Cheap Rupture of red blood cells
Enzyme digestion Cell wall digested,providing disruption
Gentle Expensive Micrococcus lysodeikticus treated with egg lysosyme
Solubilization Detergents solubilize cell membrane
Gentle Moderate-expensive
Bile salts acting on E. coli
Lipid dissolution Organic solvent dissolves in cell wall, and so destabilizes it
Moderate Cheap Toluene disruption of yeast
Alkali treatment Saponification of lipids solubilizes membrane
Harsh Cheap
Mechanical
Homogenization(blade type)
Cells chopped in Waring blender
Moderate Moderate Animal tissue and cells
Grinding Cell ruptured by grinding with abrasives
Moderate Cheap
Ultrasonication Cells broken withultrasonic cavitation
Harsh Expensive Cell suspensions at least on small scale
Homogenization(orifice type)
Cells forced through small hole are broken by shear
Harsh Moderate Large scale treatment of cell suspensions, except of bacteria
Crushing in ball mill
Cells crushed between glass or steel balls
Harsh Cheap Large scale treatment of cell suspensions and plant cells
Table 1. Cell Disruption Technique
Chemical Methods (not popular in industry)
Enzyme digestion Enzyme costAlkali treatment Harsh condition, degradation
(PHB separation) Osmotic Shock
Cells are put into pure waterSolutes in the cells cause an osmotic flow of water into the cell
(Note: Plant cell are difficult to be burst.)
Solubilization : by detergentConcentrated detergent solution is added to disrupts the cell membraneDetergent - Ex: SDS (Sod Dodecylsulfate)Solubilize cell wall lipid
Figure 1. Chemical structures of selected surfactants.
Lipid Dissolution
A volume of solvent( toluene) about 10% of the biomass is added to a cell suspensionThe cell wall lipid is solubilized.
Mechanical Disruption
Figure 2. Homogenizer Assembly. (a) A typical homogenizer and (b) a homogenization valve. Cell passing through this valve areruptured by both shear and mechanical stress.
Homogenizer
(a) (b)
Figure 3. Homogenization versus time. Mechanical disruption of cells reduces particle size but some may also denature some of the products in the cell.
*How long for operation?
Time, min
Alcohol DehydrogenaseActivity
Fumarase ActivityApparentParticle Size
Ball Mill (Sand Grinder)
Feed in
Cooling Jacket
screen
Sand (bead)
Figure 4. Schematic diagram for ball mill equipment.
*batch, continuous type*paint, dyestuff industry
* 멧돌
Enzymatic Lysis• dissolve the outer mannoprotein layerproduction of protoplasts from yeast and bacteria
• endo-β(1,3) glucanaseLytic protease
• Preparation of lytic enzymes• Lysis experiment for various enzymes -required
Cell Disruption Equipment: Bead Mill
Sept. 21st, 2011
Esther H. Kim
Bead mill
Laboratory bead mill (Dyno mill and DMQ-07)
Production machine (DMQ-10)
Media volume 0.4L
Media volume 5.5L
Scale-up & Application
• Laboratory Scale-up
Bead mill – Grinding media• Weaknesses of the sand mill
– Transition to closed mills– ottawa sand grinding beads
• Grinding media (beads)– Steel, zirconium oxide, aluminum oxide, Si/Al/Zr mixed oxide (SAZ),
steatite (modification of talc), glass and plastics– Diameter lies in the range from 0.1 to 3 mm.– The harder the beads, the greater the intensity of dispersion.– The number of beads is proportional to 1/d3 use smallest beads
possible.• Translational and rotational movement: compressive stress and
shear
Application in research• Horizontal bead mill used for cell rupture
(a) General view, (b) details of (i) stainless steel and (ii) polyurethane impellers
Application in researchBead-mill homogenization
Lysis of microbial cells in soils and sediments for large scale
relatively inexpensive widely applicable
Compared to chemical and enzymatic method
What is a French Press?
2011 - 9 - 21
Inae Kim
Bioseparation Engineering
Contents
1. What is a French Press?
2. Principle
3. Operation
4. Characteristics
5. Manufacturer
What is a French Press?
기계적으로 세포를 파괴하는 방법
염록체 , 혈구세포 및 단세포 생물의 분해와 동물조직 및 생물체 입자의 균등질 (homogenate) 제조에
이용
세포핵은 손상시키지 않고 세포벽만을 분해Sonication 보다 균일하고 완전한 분해 가능
고압 ( 최대 40,000 psi) 과 빠른 감압을 이용 단단한 세포도 쉽게 분해 가능
Stainless steel 샘플의 오염 방지Figure 1. French Press.
Principles of the French Press
Figure 3. Diagram of French Press Cylinder.
Flow valve
Outlet tube
Cylinder body
Piston
Figure 2. French Press Cylinder.
Sample
Operations of French Press
① Pump ON/OFF
② Ratio Selector valve (MED/HIGH)
- 유효 피스톤 면적 결정
③ Pressure valve
(increase/decrease)
Figure 4. Installed French Press cylinder in the press .
①
②
③
Figure 5. French Press .
Characteristics of the French Press
장점
-시료의 생화학적 성질 보존
-시료의 손실 위험이 적음
-시료 전처리 과정이 없음
-크기가 작은 시료는 거의 완전히 분해 가능
단점
- 시료의 부피가 클 때는 부적절
- 부품의 무게가 무거워서 조작이나 세척이 다소 어려움
- 배출구가 막힐 수 있음
Manufacturers of the French Press
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