Fermentation Scheme of Bacillus subtilis

1、 Introduction

Bacillus subtilis, as a widely used industrial microorganism, plays an important role in the fields of biofertilizers, biopesticides, enzyme preparations, and food industry due to its strong environmental adaptability, efficient metabolic capacity, and safe production characteristics. This program aims to provide a comprehensive and detailed Bacillus subtilis fermentation plan, covering all aspects from strain selection and preparation to storage and application.

2、 Selection and preparation of bacterial strains

1. Strain selection: Select high-quality Bacillus subtilis strains that have been screened and identified based on specific application requirements, such as the effectiveness of biological fertilizers and enzyme production. Ensure high purity, strong activity, and genetic stability of the bacterial strains.

2. Strain activation: Inoculate the frozen strains onto a suitable activation medium for revival cultivation. The cultivation conditions are generally suitable temperature (such as 30 ° C), appropriate ventilation rate, and appropriate pH value (such as 7.0-7.5).

3. Expanded cultivation: Inoculate the activated bacterial strain into an expanded medium containing rich nutrients for multi-stage expansion cultivation to increase bacterial concentration and prepare for subsequent fermentation.

3、 Preparation of culture medium

1. Ingredient selection: Based on the growth requirements and metabolic characteristics of Bacillus subtilis, select appropriate carbon sources (such as glucose, sucrose), nitrogen sources (such as yeast extract, peptone), inorganic salts, and trace elements.

2. Preparation method: weigh each component according to the preset proportion, dissolve it in deionized water, adjust the pH value to the appropriate range, and fully mix it evenly. Finally, sterilization treatment is carried out to ensure aseptic operation.

4、 Fermentation condition setting

1. Temperature control: Set an appropriate fermentation temperature, usually 30-37 ° C, to ensure the normal growth and metabolic activity of Bacillus subtilis.

2. pH adjustment: By adding acid-base regulators, the pH value of the fermentation broth is maintained within the optimal range for the growth of Bacillus subtilis, usually 7.0-7.5.

3. Ventilation management: Adjust the ventilation volume according to fermentation needs to ensure sufficient oxygen supply to promote aerobic fermentation or create an appropriate anaerobic environment.

4. Stirring and Mixing: Use appropriate stirring methods and speeds to ensure even distribution of nutrients and oxygen in the fermentation broth, promoting bacterial growth.

5、 Vaccination and Fermentation

1. Inoculation amount: Determine a reasonable inoculation amount based on the concentration of the bacterial strain and the capacity of the fermentation tank, generally 1% -5% of the volume of the fermentation broth.

2. Fermentation process: Fermentation is carried out under set fermentation conditions, and key parameters such as bacterial concentration, metabolite content, and fermentation broth properties are regularly monitored in the fermentation broth.

6、 Fermentation liquid treatment

1. Collection: After fermentation, collect the fermentation broth into a suitable container.

2. Solid liquid separation: Separation of bacterial cells from solid impurities in the fermentation broth using methods such as centrifugation and filtration.

3. Concentration and drying: Concentrate and dry the bacterial cells as needed to prepare the desired formulation form (such as powder, granules, etc.).

7、 Quality inspection

1. Bacterial content: Determine the content of Bacillus subtilis in the fermentation broth or final product to ensure compliance with the specified standards.

2. Activity evaluation: Evaluate the metabolic activity and functional characteristics of bacterial cells through specific enzyme activity tests or biological activity experiments.

3. Safety testing: Conduct safety assessments such as microbial contamination testing and heavy metal content testing to ensure that the product meets relevant standards and regulatory requirements.

8、 Optimization and improvement

1. Process optimization: By adjusting fermentation conditions (such as temperature, pH value, aeration rate, etc.) and formula composition (such as types and ratios of carbon and nitrogen sources, etc.), fermentation efficiency and product quality can be improved.

2. Technological innovation: Introducing advanced fermentation technologies and equipment (such as high-throughput screening technology, automation control systems, etc.) to enhance the intelligence and automation level of the fermentation process.

3. Cost control: Optimize raw material procurement and formula design to reduce production costs; Improve the utilization rate and energy efficiency of fermentation equipment, reduce waste and emissions.

9、 Storage and Application

1. Storage conditions: Store Bacillus subtilis preparations in a cool, dry, and well ventilated environment, avoiding direct sunlight and high temperature and humidity.

2. Shelf life management: Set a reasonable shelf life and label it on the product packaging; Regularly conduct product quality testing to ensure its effectiveness.

Application promotion: Develop appropriate promotion plans based on the characteristics and application fields of Bacillus subtilis; Strengthen communication and cooperation with customers to provide customized products and services.