L-Isoleucine

L-Isoleucine is one of 20 proteinogenic amino acids. L-Isoleucine is an essential amino acid.

α-Acetolactate Synthase [Culture Solution (Strain Culture)] → Strain Expansion Culture [Fermentation] → [30-31℃, 60h] Fermentation Liquid [Filtration] → [Heating] Upper Layer Liquid [Oxalic Acid, Sulfuric Acid (Acidification) ]→[Filtration] Filtrate [H+732 Resin]→[(Adsorption Separation)] Eluent [Concentrate]→[Vacuum Distillation] Concentrate [NH3 water (neutralization)]→Precipitation [Water (refined)]→ Crystallization [Drying at 105°C]→L-isoleucine finished seed culture medium consists of glucose 2%, urea 0.3%, corn steep liquor 2.5%, soybean cake hydrolysate 0.1% (calculated as dry soybean cake), adjust pH6 .5, keep warm at 118-120℃ and sterilize for 30min. First-level seed cultivation. Add 200ml of the above-mentioned medium to a 1000ml conical flask, inoculate a ring of beef extract slant AS (ie, α-acetolactate synthase) 1.998 strain, culture at 30℃, stroke 7cm, frequency 105 times/min, 16h. Secondary seed cultivation. The second-level seed medium is similar to the first-level seed medium, with the addition of 0.4% rapeseed oil, an inoculation volume of 3.5%, and cultivation for 8 hours. In this way, a sufficient amount of strains are cultured step by step. Fermentation and acidification fermentation broth is composed of ammonium sulfate 4.5%, soybean cake hydrolysate 0.4%, corn steep liquor 2.0%, calcium carbonate 4.5%, adjusted pH to 7.2, starch hydrolysis reducing sugar initial sugar concentration 11.5. Then add the above fermentation broth for 3t in a 5m3 fermentor, heat and keep at 118-120°C, control pressure 1.1×105Pa, sterilize for 30min, immediately cool to 25°C with ice brine, connect 1% strains, 180r/ Stirring and holding at 30-31°C at min speed, fermentation at 0.21L/min aeration for 60h, continuously adding urea to 0.6% and ammonia to 0.27% between 24-50h. After 60h of fermentation, the fermentation broth was heated to 100°C and held for 10 minutes. After cooling, filter and remove the bacteria. The filtrate is processed with industrial ammonium sulfate and oxalic acid to pH3.5, and the filtrate is filtered. After separation and concentration, the above filtrate was flowed through the hydrogen type 732 ion exchange resin (400mm×1000mm) at a flow rate of 1.5% of resin per minute, then the resin column was washed with 100L of deionized water, and finally at 60℃, 0.5mol/L Ammonia is eluted at a flow rate of 3 L/min, and the eluent is collected in steps. The combined eluates with pH 3-12 were concentrated at 70-80°C under reduced pressure to a viscous state. Add deionized water to 1/4 of the original volume, and then concentrate to a viscous state, catch ammonia, repeat this three times. Decolorization, concentration, and neutralization Add deionized water to 1/4 of the original volume of the concentrated viscous material, stir well, and add 2mol/L HCl to adjust the pH to 3.5, then add 1% activated carbon, at 70-80℃ Insulate with stirring and decolorize for 1h. Filter and concentrate the filtrate under reduced pressure. Finally, add 2mol/L HCl to adjust the pH to 6.0. Incubate at 5°C. Leave to settle overnight. Suction and filter the precipitate to dry at 105°C to obtain a semi-finished product. Refining and taking 10kg semi-finished product, adding 8L concentrated hydrochloric acid, 20L deionized water, heating and stirring to dissolve, then adding 10kg NaCl to saturation, adding industrial alkali to adjust the pH to 10.5, filtering the filtrate, adding alkali to adjust the pH to 1.5, holding 5 Place the precipitate overnight at ℃, filter and collect the precipitate, dissolve with 80L deionized water by heating and stirring, then add appropriate amount of NaCl and 1% activated carbon, stir at 70-80 ℃ for 1h, filter and take the filtrate, concentrate under reduced pressure to the appropriate concentration, use Adjust the pH to 6.0 with ammonia, incubate at 5°C overnight to precipitate the crystals, filter the crystals, and dry at 105°C to obtain the finished L-isoleucine.

antipsychotic.Used as amino acid injection, compound amino acid infusion, food additive.Nutritional supplements. L-isoleucine is one of the essential amino acids of the human body,It is used in biochemical research and as a nutritional supplement in medicine.