BHI Broth

General-purpose nutrient-rich liquid medium for growing Sporosarcina pasteurii starter cultures.

BHI Broth, v1.0 Kathryn E. Caruso · 0009-0003-2436-1791 Foreman Lab · Center for Biofilm Engineering, Montana State University Updated March 2026

How to cite this protocol Caruso, K.E. (2026). BHI Broth, v1.0. Foreman Lab, Center for Biofilm Engineering, Montana State University. https://kathryncaruso.github.io/methods/bhi-broth/

Using Difco™ Brain Heart Infusion Broth

Overview

Brain Heart Infusion (BHI) broth is a general-purpose, nutrient-rich liquid medium. Used in this project for growing Sporosarcina pasteurii starter cultures as a positive control in ureolytic activity assays.

Materials

  • Difco™ Brain Heart Infusion (BHI) powder
  • Purified water
  • Autoclave-safe bottle (use ≤50% capacity)
  • 50 mL Falcon tubes (for dispensing)

Final Concentrations

Component Final Concentration
Brain Heart Infusion 37 g/L

Procedure

  1. Suspend 37 g of BHI powder in 1 L of distilled water.
    • Important: Fill bottle to no more than 50% capacity.
  2. Heat to dissolve.
  3. Cool, mix well, and distribute into final containers.
  4. Autoclave at 121°C for 15 minutes.

Batch Variations

Batch Size BHI Powder Purified Water Notes
Small 1.85 g 50 mL ~5 Falcon tubes at 10 mL each
Medium 3.7 g 100 mL ~10 Falcon tubes at 10 mL each
Large 9.25 g 250 mL ~25 Falcon tubes at 10 mL each
Full 37 g 1 L ~100 Falcon tubes at 10 mL each

Dispensing

  1. In a Biosafety Cabinet, aseptically dispense 10 mL of sterile BHI broth per 50 mL Falcon tube.
  2. Cap tightly and label with medium type and date.

Storage

  • Store sterile broth at 4°C.
  • Label with medium type, date of preparation, and initials.
  • Stable for several weeks refrigerated. Discard if turbidity develops.

Notes

  • For S. pasteurii starter cultures, inoculate a single Falcon tube (10 mL) from a freezer stock using a sterile loop — see S. pasteurii Starter Culture SOP.
  • BHI broth does not contain agar. For BHI agar plates, see BHI Agar SOP.