In 2022, the Center for Application received the production process for a biological preparation containing Rhodococcus sp. bacteria capable of degrading aromatic hydrocarbon compounds in wastewater. This was part of the project titled “Research on the creation of a biological preparation containing Rhodococcus sp. bacteria that degrade aromatic hydrocarbon compounds in wastewater,” led by Dr. Nguyễn Thị Phi Oanh, with Can Tho University as the host institution. Most bacteria of the genus Rhodococcus are non-toxic; some strains are considered potential bacteria studied for application in treating environmental pollutants. Rhodococcus bacteria have relatively large genomes and carry multiple metabolic pathways to degrade a variety of natural and synthetic compounds such as straight-chain hydrocarbons, mono- and polycyclic aromatic hydrocarbons, nitriles, cholesterol, and lignins.

The production process consists of four basic steps with the following tasks:

1. Primary culture preparation: Cultivate bacteria in liquid medium to produce the primary culture (6 mL suspension). This includes preparing the medium and equipment, inoculating the strain into the medium, and incubating for 24 hours on a shaker (200 rpm) at room temperature.
2. Secondary culture preparation: Prepare the medium and equipment, inoculate 6 mL of the primary culture into 6 liters of medium, and incubate for 24 hours on a shaker (200 rpm) at room temperature for each cultivation batch.
3. Carrier preparation: Mix according to the researched ratio into 500 g per bag, sterilize by wet heat twice. Dry at 40°C for 24 hours after sterilization. Sterilize aluminum bags with alcohol and UV in a sterile cabinet. Divide the carrier material into 500 g bags.
4. Preparation mixing: Collect the bacterial suspension after incubation, add vitamin B12 to the suspension before mixing it with the carrier. Mix 50 mL of bacterial suspension into each 500 g carrier bag. Vacuum-seal the bags and label them.

After producing the 500 g preparation, it was found that the bacterial density was well maintained in the researched carriers. Evaluation of the degradation ability of BTX compounds showed feasible results and potential applications for environmental protection and public health.