Monday, February 9, 2009



Everyone dealing with fermentors knows that mixing is one of the most important parameters that affect the fermentation process. Put it this way, in order to support the high growth of microorganisms and the production of high concentration of fermentation products, mixing is necessary.

Mixing is essential in order to provide homogenous condition throughout the fermentor required the optimum growth of the microorganisms. Homogenous conditions within the fermentor will allow efficient mass transfers of nutrients, heat and oxygen throughout the fermentor. It will also eliminate formation of gradients and built up of toxic products

However, even though mixing is crucial to the fermentation process, it needs to be properly executed as there are the good, bad and ugly sides of mixing which have impact on the fermentation process.

One of the sensitive sides of mixing is the effect of shearing. In fermentor as the impeller rotates it creates a flow. Shearing forces will be generated where there are velocity gradients between two points in the liquid flow. Differences in velocity gradients in shearing could occur between the same or different phases in the broth such as between liquid and liquid, liquid and gases and liquid and solids.

Under non turbulent or laminar flow, shearing still occur but would not be significant in fermentors as high rate mixing is often the order of the day.

In a simple model of visualization we could see shearing forces as forces that physically stretch, tear or wear out surfaces. Thus, in this context if uncontrolled shearing forces are damaging to the microorganisms and the products formed. The intensity of shearing are often related to the amount of physical force or mixing power exerted into the system. Higher turbulence would relatively lead to increased or more powerful turbulence.

There are many areas or zones in the fermentor which are strongly affected by the shearing forces generated by mixings. Most intense shearing is known to occur in the mixing zones of the impellers, and especially at the tip of rotating impellers. Shearing forces could also occur in the region of the baffles or where strong air sparging occurs.


Shearing may result in the reduction of the boundary layer. This will increase the rate of mass transfers across the boundary layer between the microbial cell and the environment


Shearing can result in damages to the microorganisms and directly will affect the efficiency of the fermentation process. The effect of shearing on the microorganisms much depends on the morphology and growth forms of the microorganisms. Filamentous fungi will be easily tangled and damaged during mixing and shearing.

In the case of unicellular microbial cells the effect of shearing is not so much on the damage to individual cells but to the microbiological aggregates. Rarely do microorganisms occur as independent single cells in fermentors. Most, if not all occur as microbial aggregates such as microbial flocs, microbial mats.

Under these conditions the formation of the microbial aggregates is often the physiological response of the microorganisms to conditions of stress. These microorganisms will produce high amount of EPS around them in a protective response against damage.

Flocs are however not strong structures and studies in activated sludge system showed that larger flocs are easily broken down to smaller flocs under turbulence. Most of the damage by shearing occurs at the impeller tips.


Damages by shearing of the microbial cells will result in the release of metabolites which will complicate the fermentation process by increase in foaming and difficulty of recovery of fermentation products

Type rest of the post here.
Read more!

Sunday, February 8, 2009


There will be a temporary cessation of blogging activities in this blog for the next two weeks as the author will be in South Korea visiting Myongji University, Seoul National University and Korea Institute of Science & Technology.

Blogging activities will resume after the period
Thank You

Type rest of the post here.
Read more!

Friday, February 6, 2009




Pharmaceutical industries are big bucks! Just see the volume of drugs produced by the giant pharmaceutical manufacturers and the record billions dollars profit shown every year. Yet these mega companies are always looking for profitability and finding ways to cut the costs of their production by trying to cut the costs of producing these drugs.

Some of these pharmaceuticals are produced by fermentation such as antibiotics, vaccines and biologics. The cost of production of these fermentation derived pharmaceuticals is sky high due to the high cost of capital investment in equipments and facilities. In view of this problem many of these giant pharmaceuticals companies tries to outsource their production or manufacturing by looking for contract manufacturing beyond their shores.

Asia has always been a very attractive site for contract manufacturing as it fulfills all the requirements needed for successful contract manufacturing ventures. It should be noted that outsourcing manufacturing capabilities is not a new phenomena as the Japanese were all ready at it as in the Fifties.

The most popular countries in out sourcing pharmaceutical contract manufacturing currently are India and China. Even Malaysia do not wants to be left out on this rich gravy train.

However, in pharmaceutical contract manufacturing is not all good news. Both the proprietor and the contract manufacturer face a lot of problems and issues. It may look good on paper, but in reality there are a lot of bumps to overcome and risks to be taken.


The first question that is often asked is why do the proprietary holders want to source out pharmaceutical contract manufacturing?

There is really one reason why pharmaceutical fermentation industries outsource their manufacturing or production, that is, to cut costs and increase their profitability. In this world of free market competition, the ability to reduce the cost of products will be crucial to the survival and profitability of the company. The advantages of foreign contract manufacturing include:

1 favorable tax benefits for the parent company, allowing them to
reduce overall tax liabilities and increase profits.
2 Other advantages over in-house manufacturing, including lower
costs, flexibility, access to external expertise and reduced capital.

The trouble is that the problem is not solved by simply carrying out contract manufacturing and just gets the benefits. As stated earlier contract manufacturing is not without risks.

There are many considerations to be taken before a suitable contract manufacturer can be hired such as:

1 Have they got the proper industrial facilities to carry out the manufacturing?
2 Do they have the right people and expertise to ensure the smooth running of the contract manufacturing?
3 Can the contract manufacturer produce the products to the expected quality and standards?
4 Have the contract manufacturer sufficient industrial experience and track records to carry out such production?
5 Can they justify the correct costing and tenders to compete with other contract manufacturers?

It is a well known observation that most of the experts in the fermentation of pharmaceuticals are new and have very little experience in running industrial level contract manufacturing and scale up productions. Most of them are probably so new and are in their baby steps phase of the learning curve to pharmaceutical fermentation contract manufacturing. Most of the experts are perhaps new lecturers in universities who are too academic inclined and not exposed to the practicals of production floors. Their levels of fermentation are perhaps still at the level of Mickey Mouse projects!

True! We do have facilities for fermentation, but most are just pilot plant scale and not really geared for industrial fermentations. This is in the case of the Universities fermentation suite or pilot fermentation unit.

Even though we may have companies that supposedly have the capacity to do contract manufacturing, but in reality they do not function as professional pharmaceutical fermentation contract manufacturer. All they can show are a few big size shiny fermentors and a few staff in gleaming white lab coats. In fact they are more involved in the propagandistic public exhibitions of what they can promise. A visit to their website will expose a lot of weakness and where tons of money is poured down the drain with no returns

A facility for proper industrial scale fermentation pharmaceutical contract manufacturing must be able to show its ability and capacity to produce industrial scale production. The facilities must be adaptable enough to be used for various types of pharmaceutical fermentations. In that sense the company should not show the priority of exhibition booths to fulfill the visiting school students

These companies should be more opened to the public of the successful tenders that have been executed and not just reports of visits and exchange of MoUs.


As for the country or company that offer contract manufacturing burdened by high capital costs and need for specialist educated force. Also the demand for facilities by companies must be high to sustain the company and make sufficient profits out of the venture.

They must be able to produce products to the specifications of the clients.

Their facilities and equipment must be adaptable to various specific demands of clients and they must have the capacity to carry out large scale production. Everything is ok if contract is profitable and booking books are full and you have long term contracts. If not you are going to have many stainless steel white elephants! And a lot of research staff and laboratory coated technicians walking aimlessly at costs!

Poor marketing is another problem. As they say it even if you have poor products good marketing will generate sales. If you have good product but poor marketing no one will buy your products

But out sourcing is not without risks as there are many factors to consider before choosing which country to invest or outsource. In certain cases, if no careful considerations are given the whole outsourcing exercise could be a failure with serious economic, legal and social consequences.


Pharmaceutical fermentation contract manufacturing is not as simple as contract manufacturing for garments and shoes where all you need are simple production lines, simple machinery and thousands of workers. Far from it, pharmaceutical fermentation is very technologically complex that require well qualified experts and very sophisticated equipments and facilities. It is a very costly operation which put the investor into a lot of possible financial and even regulatory risks. Its products affect human health and safety directly.

Pharmaceutical fermentation is not as simple as food or beverage fermentations. In biologics fermentation aseptic and clean room fermentation is mandatory. Downstream processing steps are more sensitive

The only way out of this predicament is to swallow our pride and work with other manufacturing contractors by:

1 Use facilities that are already in use to produce biologics or facilities by established companies in the region
2 Build new facilities by established contractors not by fermentor sellers or their sales men
3 Carry out joint ventures with other contractors as we did with Mitsubishi and proton cars and hoped that they do carry out technology transfers in the real sense!
Maybe the only significant advantage out of these arrangements is that we have our rights to add “ Made in Malaysia” on every products produced. He he

Type rest of the post here.
Read more!

Wednesday, February 4, 2009


I just cannot understand it. At times I feel the way the whole world discovers or respect Japanese products seems to be out of perspective. At times they regarded their products as far superior or even have the magical elixir of life!
One good example is their fermented product or koji which is used widely to seed or culture their various fermented food and beverages such as miso,soy sauce and sake. There is really nothing special about it or the great hype being associated with it. Koji is just the fermenting agent! koji can refer both to a fungus and to a food ingredient that is commonly made using rice, barley, or soybeans.
Seed koji refers the spores of the fungus Aspergillus oryzae. The fungus is a type of mold that is native only to the humid Southeast and East Asian regions.
Koji is made by sprinkling seed koji over steamed rice, barley, or soybeans and cultivating the fungus under temperature conditions suitable for its growth. As the fungus propagates, enzymes break down the grains' starch and proteins into sugars and amino acids.
The main factors determining are type of koji and type of substrate used. Different types of koji are used for different type of fermented food. Even for sake there are various types of koji seeds used.
Although the main microorganism for koji is Aspergillus, koji are known to contain about fifty types of enzymes. The most important enzymes in a koji are alpha amylase, glucoamylase and acid protease.
The poor reception for koji type of fermentation is probably due to the western obsession with SF than SSF

Using koji has now grown out of popularity because modern fermentation industries are always looking for automated fast fermentation under the mantra of "faster, cheaper, and more." Mass production of widely used foods by fast fermentation led to the emergence of national brands in the fermentation industry. This lead to cheaper fermented food and beverages. However the drawback is that fermentation is not simply a process you can just speed up the fermentation time and volume produced. This has the effect of affecting the quality of the fermentation products in terms of subtle flavors and rich nutrients of naturally fermented products. In trying to short cut the fermentation extraneous enzymes and additives are added. This of course will affect the fermentation process and the quality of the fermented products.


Making koji is often a family secret. Generally it takes three days
Rice- soaked in water overnight - steamed 40 minutes- cool down, scarred to facilitate fungal growth-- sprinkled with seed koji--- transfer to fermentation room
If we look at the whole koji preparation it is more an intimate play of temperature, time and humidity. Different types of temperatures are exploited and controlled to get the right koji and enzyme activities. There is a frequent use of cloth and straw wrapping to insulate the koji temperature

Type rest of the post here.
Read more!