Navigation Links
FERMENTATION BASICS

y of the solution.


2.5.2. Gas exchange and mass transfer
One of the most critical factors in the operation of a fermentor is the provision of adequate gas exchange. Oxygen is the most important gaseous substrate for microbial metabolism, and carbon dioxide is the most important gaseous metabolic product.

When oxygen is required as a microbial substrate, it is frequently a limiting factor in fermentation. Because of its low solubility, only 0.3 mM O2, equivalent to 9 mg/l, dissolves in one liter of water at 20 degrees Celsius in an air/water mixture. This amount of oxygen will be depleted in a few seconds by an active and concentrated microbial population unless oxygen is supplied continuously. In contrast, during the same period the amount of other nutrients used is negligible compared to the bulk of concentrations. Therefor most aerobic microbial processes are oxygen limited. This is the reason why the concept of gas-liquid mass transfer in bioprocesses is centered on oxygen transfer even if other gasses such as carbon dioxide, hydrogen, methane and ammonia can also be involved.

Due to the influence of the culture nutrients, the maximal oxygen content is actually lower than it would be in pure water.

The solubility of gasses follows Henry's law in the gas pressure range over which fermentors are operated. This means that if the oxygen concentration in the gas phase increases, the O2 proportion of the nutrient solution increases. Consequently the highest O2 partial pressure are attained during aeration with pure oxygen. Compared to the value in air (9 mg O2/l), 43 mg O2/l dissolves in water when pure oxygen is considered.

As temperature rises, the O2 solubility decreases. For example the solubility at 33 degrees Celcius is
'"/>

Source:


Page: All 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Related biology technology :

1. P. pastoris Fermentation using a BioFlo 110 Benchtop Fermentor
2. E. coli Fermentation Using a BioFlo 110 Bench-Top Fermentor
3. Optimizing Your Benchscale Fermentation Process
4. High Yield Protein Production from Pichia pastoris Yeast: A Protocol for Benchtop Fermentation
5. Glossary for The BioPharm Guide to Fermentation and Cell Culture
6. Fundamentals of Fermentation: Techniques For Benchtop Fermentors
7. 140-Fold Increase of Protein Achieved in Pichia Fermentation
Post Your Comments:
*Name:
*Comment:
*Email:
TAG: FERMENTATION BASICS

(Date:10/20/2014)... Convey Computer , the leader in ... State University won first place in the 2014 ... the team’s solution achieved the highest overall performance in ... place finisher. , Experts from all segments of the ... challenge, using a variety of design tools, hardware and ...
(Date:10/20/2014)... Inc. (TSXV: BRM) ("Biorem" or "the Company") today announced four new ... and provides a good start to Q4.  The orders are for ... and one in the Middle East . ... Peter Bruijns , President & CEO. "Total bidding activity and ... have been for any complete year since the company has tracked ...
(Date:10/20/2014)... Oct. 20, 2014  GenVec, Inc. (NASDAQ: GNVC ... , Ph.D., from its board of directors effective on October ... 2003, and served as its chairman from June 2006 to ... Nominating and Corporate Governance and Audit Committees of the board.  ... a decade of dedicated service to GenVec, and its stockholders," ...
(Date:10/20/2014)... 2014 OncLive® is ... Center at Thomas Jefferson University has joined its ... Strategic Alliance Partnership program, the Sidney Kimmel Cancer ... raise awareness of the Center’s cutting-edge research programs, ... Clinicians and other health care professionals from the ...
Breaking Biology Technology:Team from Iowa State Wins 2014 MemoCODE Design Contest Using Convey HC-2ex 2Team from Iowa State Wins 2014 MemoCODE Design Contest Using Convey HC-2ex 3Zola P. Horovitz To Retire From GenVec Board 2Sidney Kimmel Cancer Center at Thomas Jefferson University Partners With OncLive 2Sidney Kimmel Cancer Center at Thomas Jefferson University Partners With OncLive 3
... Madison, Wis. - Matt Miszewski will leave his ... at the end of February, about the time an audit ... released. , ,Miszewski, who likely will pursue opportunities in the ... e-mail and praised them for revolutionizing the use of technology ...
... Wis. - Wisconsin companies raised more venture capital in ... in both categories, according to report from Ernst & ... ,Companies in Wisconsin reported 12 venture deals in 2006, including ... a Madison-based maker of genomic research tools, for a total ...
... MailFoundry , a provider of anti-spam appliances and solutions, ... spam tactics known as botnet e-mail harvesting ... company's chief executive said the new RedListing anti-spam layer, produced ... no false positives and realtime detection capabilities. , ,David C. ...
Cached Biology Technology:Miszewski to depart as state IT audit wraps up 2Wisconsin fares slightly better in venture capital chase 2Wisconsin fares slightly better in venture capital chase 3
(Date:10/16/2014)... Respiratory Syncytial Virus causes severe respiratory tract infections ... each year. Scientists at VIB and Ghent University ... to counteract this common virus infection. , ... strategy that paves the way for the development ... a virus that causes suffering in numerous small ...
(Date:10/15/2014)... 15, 2014 Sandata Technologies, LLC, an ... community-based care, today announced it released a case ... Electronic Visit Verification™ Solution (EVV™)  for Quality Care ... health company founded in 1996 and has five ... The study details the challenges facing ...
(Date:10/15/2014)... Johannes Gutenberg University Mainz (JGU) as a full ... to maintain a significant nationwide standing in the ... of Johannes Gutenberg University Mainz as a full ... the national and international competition for the best ... can be proud that Mainz University has been ...
Breaking Biology News(10 mins):New perspectives for development of an RSV vaccine 2Sandata Announces Case Study with Quality Care Services, Inc. 2Johannes Gutenberg University Mainz joins Germany's Gauss-Allianz as a full member 2Johannes Gutenberg University Mainz joins Germany's Gauss-Allianz as a full member 3
... will soon host a round-the-clock, robotically choreographed hunt for ... leads a diverse team of scientists whose goal is ... dioxide from a power plant,s exhaust, before it leaves ... betting on a recently discovered class of materials called ...
... Scientist Jon Chase once worked in a lab that set up ... "We would try to duplicate pond communities with a given ... in each pond, and five of these species, and eight of ... grams of that and ,sproing, every replicate would do its own ...
... People often have strong opinions on the "right" firmness ... some cell types have similar preferences for their ... Institute of Standards and Technology (NIST) and the National ... offer cells a three-dimensional scaffold that varies over a ...
Cached Biology News:The search for improved carbon sponges picks up speed 2The search for improved carbon sponges picks up speed 3The great pond experiment: Regional vs. local biodiversity 2The great pond experiment: Regional vs. local biodiversity 3Scaffold gradients: Finding the right environment for developing cells 2