Production method of Bacillus subtilis antimicrobial lipopeptide and application of Bacillus subtilis antimicrobial lipopeptide in piglet feeds

[0014] Example 1

[0015] Using a 5000 L fermentor, the best fermentation process conditions after 500 L amplification are used to treat Bacillus subtilis ( Bacillus subtilis ) FmbJ (preservation number: CGMCC No. 0943, see patent publication number: CN1477189) for fermentation production. The best fermentation process parameters are: temperature 28~35℃, stirring speed 180 r∕min, ventilation 80 m 3 / h, tank pressure 0.10~0.12Mpa, pH 7.0, soybean oil 0.3%.

[0016] Take Bacillus subtilis ( Bacillus subtilis ) Strain fmbJ, seed medium expansion culture, seed medium: tryptone 10.0 g, yeast extract 5.0 g, NaCl 5.0 g, distilled water 1000 ml, pH 7.2; volume ratio 2~5% inoculation, 28~35℃, 5000 L fermentor for liquid submerged fermentation for 30 to 48 h, liquid fermentation medium: glucose 20.0 g / L, tryptone 5.0 g / L, sodium glutamate 2~5%, MgSO 4 0.5 g / L, KCl 0.5 g / L, KH 2 PO 4 1 g / L, FeSO 4 0.15 mg / L, MnSO 4 5.0 mg / L, CuSO 4 0.16 mg / L, pH7.0; fermentation process

[0018] Example 2

[0019] Using a 5000L fermentor, the optimum fermentation process conditions after 1000L amplification Bacillus subtilis fmbJ conducts fermentation production. The best fermentation process parameters are: temperature 32℃, stirring speed 180 r∕min, ventilation 80 m 3 / h, tank pressure 0.10~0.12Mpa, pH 7.0, soybean oil 0.3%.

[0020] The industrial centrifuge used is a disc centrifuge with a speed of 6000 r / min to remove bacteria, and then spray drying is used for drying. The process is: temperature 210℃, fan speed 70 rpm, excipient: maltodextrin: porous starch = 6-9:1, the recovery rate of antimicrobial peptide is 54%, and the antibacterial potency is 20000~ 70000 IU / g dry powder.

[0021] Example 3

[0022] 360 piglets were selected from 28-day-old weaned long x large binary hybrids and randomly divided into 4 treatment groups according to the principle of half males and females with different sources. Each treatment has 6 repetitions, 15 per repetition, and each piglet weight. Similar (P> 0.05). The basic diet is corn-soybean meal type, and the nutritional requirements refer to NRC (1998) "Nutritional Needs of Pigs" ileal apparent digestible amino acid model, diet composition and nutritional content. The treatment groups were the blank control group (group C) fed with a basal diet (the basal diet did not contain antibiotics and antimicrobial lipopeptides), and the antibiotic control group (AC) was fed with 5 mg / kg of flavomycin in the basal diet , Test? Bacillus subtilis fmbJ antimicrobial lipopeptide 2000 IU / kg was added to the basic diet. The pre-test period is 3 days and the test period is 28 days.

[0023] The 28-day average body weight of the group s