In the first manufacture phase, the microorganism is prepared as a manufacture strain in a laboratory. The best breeding colony of the microorganism is selected and left to grow for several days. It is cultivated in test tubes first, then on laboratory plates and Erlenmeyer flasks, each time in a strictly sterile environment. Later on, the selected and well-grown microorganism is transferred into fermenters to grow for several days to reach an appropriate size. Then the content of an inoculation fermenter is poured into large fermenters.
The process of Talaromyces purpurogenus fermentation is a manufacturing secret which is patented. It is a complex biotechnological process which transforms Talaromyces purpurogenus is placed for several days inside the fermenter into a type of water microfungi. The microorganism is very sensitive, it needs specific conditions for growth, such as a constant temperature and pH, adequate nutrition, pressure within the tank and a sufficient amount of supplied and equally spread oxygen. The fermentation process is very demanding and its inhibition at this manufacture phase may lead to a growth cessation and failure to continue this costly process. This is why the fermentation is managed and monitored via control systems technology, which records all the measured values every second of the manufacture process. A sterile environment is needed for the entire fermentation to avoid contamination and the final product degradation.
After the fermentation stage, the final product is filtered on filtration equipment. In the first filtration stage the product goes through a filter press which separates the largest parts of the microorganism - waste biomass from the production part. This is consequently processed in a high speed centrifuge which separates the residual biomass. Moreover, a microfiltration membrane follows to separate microscopic particles. The last stage of product filtration is nanofiltration. It separates low molecular compounds such as water and simple salts using a high pressure which produces a very little amount of the final product in a liquid form.
In the fermentation tanks the product increases in volume up to several thousands of litres; after fermentation and the following filtration the product is concentrated and its yield is only a few litres.
The last manufacture phase is drying which takes place in a spray dryer at high temperatures. The substance is pressed using high-speed devices and an atomizer into a heated tank at 150-250°C. The final product is dark red powder of appropriate characteristics and qualities, in other words BIOCOL.
Overall, the manufacture of the active substance is very demanding in terms of energy, technology and time. However, it is eco-friendly and almost waste-free. The residual mycelium is used for chitosan and glucosamine processing. The rest is utilised in agriculture as an effective fertiliser.
Description of individual manufacture stages:
Fermenters are large stainless steel tanks with agitators and a double casing to enable heating up or cooling down. Fermentation tanks are equipped with sensors to monitor the entire manufacture process. The variables such as temperature, pH, stirring speed, amount of oxygen and pressure are checked. All is managed and controlled by the technology system using special IT applications. Fermentation tanks have several inputs that include air input and output, hot steam, input for growth medium and output for the final product. The tanks and their inputs and outputs are sterilised with hot steam at 130°C prior to fermentation to avoid contamination and the product degradation.
Filter press is a piece of equipment used for separation of solids (biomass) from the fermentation solution; they form in a bioreactor during fermentation and are not desirable in another part of the production process. The filter press works on a filtration basis - it collects solid parts from the filtered solution onto filter cloths. These are on filter frames that have some space in between, called a chamber where the collected solids form a filter cake. The filter press is commonly used in wine industry or the wastewater treatment plants.
Centrifuge is used for separating solids, called biomass fragments that were not collected by the filter press, from the liquid called product containing fermentation medium, it uses a monolithic bowl. During decanting, the centrifugal force helps to speed up the sedimentation process in which the higher density phase settles. When applying decantation to separate solids from liquid, the solids are moved in radial direction through the liquid and accumulate on walls of the bowl where they are "blasted" at time intervals with compressed air into a collection vessel.
Microfiltration is a device which separates solids of 0.01-10μm under certain pressure through the filter membranes. Microfiltration purifies the product from particles of size of bacteria. This device is commonly used in the food industry, pharmacy and metallurgy. It is often used as a pre-treatment for nanofiltration.
Nanofiltration is the most modern filtration technology. Nanofiltration membranes separate under pressure some hardly perceptible pores of 300 Daltons in size. The size of separated compounds is expressed in molecular weight rather than length units. In this stage the product is concentrated to a consistency which is suitable for the next step – drying.
Spray dryeris equipment which is capable to dry the product faster, from sprayed medium using the high speed atomizer and high temperatures inside the chamber, before it hits the wall of the collection vessel. The rotation speed and the product dosage take place at 18,000 rotations per minute and 150-250°C.