The Composition Of Media

LB Medium

Yeast extact 5g

Peptone 10g

NaCl 10g

Agar 1-2%

Distilled water 1000ml pH 7.0

Boil the mixture in autoclave at 121℃ for 30min

Range of applicationb: Escherichia.coli

MRS Medium

Peptone 10g

Beef extract 10g

Yeast extact 5g

K₂HPO₄ 2g

Tween 80 1ml

Diamine citrate 2g

Na-acetate 5g

MgSO₄.7H₂O 0.5g

MnSO₄.H₂O 0.25g

Glucose 20g

Agar 1-2%

Distilled water 1000ml Adjust pH to 6.4-6.8

Boil the mixture in autoclave at 115℃ for 20min

Range of application: Lactobacillus bulgaricus

2.5% glycocoll SMRS is MRS supplemented with 2.5% glycocoll 0.5mol/L saccharose, 20mmol/L MgCl₂,20mmol/L CaCl₂

SMRSMC is MRS supplemented with 0.5mol/L saccharose, 20mmol/L MgCl₂,20mmol/L CaCl₂

Hogg-Jago glucose broth(HJG) medium

Tryptone 30g

Yeast extract 10g

Beef extract 2g

KH₂PO₄ 5g

Glucose 5g

Agar 1.5%

Distilled water 1000ml

Boil the mixture in autoclave at 115℃ for 20min

Range of application: Streptococcus thermophilus

HJGL is Hogg-Jago glucose broth supplemented with 0.5% lactose, whereas HJGLS is HJGL supplemented with 0.4M D-sorbitol

Agar plates were prepared by adding 1.5% (wt/vol) agar to the media

Competent Cell and Electroporation

The competent cell of Lactobacillus bulgaricus

The competent cell of Streptococcus thermophilus

PCR Reaction

Agarose Gel Electrophoresis

Gel Purification of DNA (Solarbio QIAquick Gel Extraction Kit)