By Matt
I ordered five mushroom strains from the Spore Depot. The five strains are Pearl Oyster, Blue Oyster, Reishi, Enoki and Shiitake. They are shipped as spores in liquid culture in 10 ml syringes.
Being a biochemist I have worked with supplemented Agar (typically LB Agar) to grow bacteria and therefore am very familiar with the procedure. I have also propagated different beer brewing yeast strains on malt extract Agar when trying to cut back on the cost of homebrewing. Yeast are single-celled microorganisms that are classified, along with molds and mushrooms, as members of the Kingdom Fungi, as such we are also able to propagate mushroom spores on malt extract agar.
The recipe is 20 grams of Agar, 20 grams of Malt Extract in 1000 mls of distilled water. I use telephone brand Agar-Agar available at most Asian grocery stores and Muntons light extract available at any homebrew shop or online. Since I don’t currently have access to cheap petri dishes, I am using glass pint jars that are very squat (Ball Collection Elite Wide Mount 16Oz Pint Jars). I first make a half recipe (500 mls worth) by mixing 10 grams of Agar, 10 grams of malt extract in 500 mls of distilled water. It’s first incubated at room temperature for 10 minutes to let the agar hydrate, then microwaved in 1 minute intervals until the agar and malt extract dissolve, making sure to closely monitor so the liquid does not boil over. The liquid is then distributed into 5 of the jars, loosely covered with plastic lids (sold separately) and pressure cooked at 15 PSI for 30 minutes. The pressure cooker is allowed to depressurize and cool over several hours so the liquid malt extract does not boil over and can solidify. Here is the final product.
Then I made a makeshift clean hood by turning a plastic clear bin sideways and cleaning its inner surface with rubbing alcohol. A candle burns in front to promote airflow away from inside the chamber.
I opened a new sterile needle for each mushroom variety and added 2 to 3 drops from the syringe on top of the agar within the hood. I also added 2 to 3 drops to my PFK media (shown on right above) through the holes in the lids. These cultures where then stored either at room temperature or in my heated incubator.
Here you can see that the mycelium (vegetative part of fungus) has spread all the way to the edge of the jar and sent hyphae up the sides. Using a sterile blade, agar wedges can be cut from the culture and added to new jar of malt extract agar or to start a rye grain spawn jar, which is the next propagation medium when attempting to expand the amount of fungus or trying to move to the fruiting stage (make actual mushrooms.)
Here is looking down an open container where an agar wedge was cut from one fully colonized Agar jar and placed in the middle of an uncolonized jar. Once again the mycelium has taken over the entire surface of the malt extract agar.