By Admin (Admin) on Saturday, April 28, 2001 - 11:07 pm: Edit

Agar culture info
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Cooking & Usage Instructions
The flask or bottle in which the medium is sterilized should never be more than 2/3 full in order to avoid boilover.
Plug the flask or bottle with non-absorbent cotton and cover with aluminum foil to help prevent entry of external contaminants.
Sterilize all formulas for 15 minutes at 15 psi.
Remove the medium as soon as the pressure reaches "0." Oversterilization or prolonged heating will change the composition of the medium. Sugars such as dextrose or malt can "caramelize," resulting in a medium that can inhibit mycelial growth and encourage sectors (mutations). Excessive heating of medium can also cause a drop in pH, resulting in a more acid medium. It is possible to destroy completely the gelling properties of agar by prolonged heating, and this destruction is hastened as the acidity increases.
For long-term health and maintenance of sacred strains, alternate any two of the above media. This will help prevent senescence, which can occur when cultures are grown on one medium only. Store strains at 35° - 40°F; transfer every six months. In this manner, sacred strains can be maintained for years.
Never compromise the integrity of your strain library. Strains showing even a hint of senescence should be removed from the collection.

Potato Dextrose Yeast Agar
250 grams of washed, unpeeled potatoes
10 grams dextrose
1.5 grams yeast
15 grams agar
Slice potatoes 1/8 inch thick
Rinse slices clean in cool tap water
Final rinse with distilled water
Cook in distilled water until tender
Strain and set aside cooking water
Rinse potatoes with distilled water
Retain rinse water, discard potatoes
Add distilled water to make 1 litre
Bring liquid to slow boil
Add dry ingredients

Malt Extract Agar
20 grams malt extract
100 mg potassium phosphate
dibasic (K2HPO4)
100 mg calcium carbonate
9.5 grams agar
1 L distilled water

Cornmeal Dextrose Agar
25grams yellow cornmeal
2.5 grams dextrose
9.5 grams agar
500 mL distilled water

Dung extract 100.00 ml
Malt extract 5.00 g
MgSO4 x 7 H2O 0.50 g
Ca(NO3)2 x 4 H2O .72 g
K2HPO4 .25 g
Peptone 0.10 g
Agar 15.00 g
Distilled water 900.00 ml

Dung extract: Boil an average sized piece of horse dung (fresh or frozen) for two hours in 150 ml
water using a water bath; filter and use immediately




more formulas....



Agar Formulas and Info
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Agar Formulas and Info



The following are proven agar recipes specifically formulated for the in vitro culturing and long-term maintenance of Psilocybe cubensis strains:

Amaranth* Soy Agar
20 grams amaranth flour
20 grams soy flour
9.5 grams agar
500 mL distilled water
Sterilize fifteen minutes at 15 psi pressure; final pH is 6.0 and requires no adjustment.

*Amaranth, from South America, is the only grain that contains all essential amino acids; it is extremely high in L-lysine, containing up to five percent.


Oatmeal Neopeptone Agar
40 grams oatmeal or oat flour
2 grams neopeptone (optional)
9.5 grams agar
500 mL distilled water
Sterilize fifteen minutes at 15 psi pressure; final pH is 6.0 and requires no adjustment.


Modified Sabouraud's Medium
25 grams barley flour
5 grams dextrose
2 grams neopeptone (optional)
1 gram yeast extract
9.5 grams agar
500 mL distilled water
Sterilize fifteen minutes at 15 psi pressure; final pH is 5.8 and requires no adjustment.


Cornmeal Dextrose Agar
25 grams yellow cornmeal
2.5 grams dextrose
9.5 grams agar
500 mL distilled water
Sterilize fifteen minutes at 15 psi pressure; final pH is 6.0 and requires no adjustment.


Barley Malt Extract Agar
40 grams barley flour
2 grams malt extract
1 - 2 grams yeast extract (optional)
9.5 grams agar
500 mL distilled water
Sterilize fifteen minutes at 15 psi pressure; final pH is 6.0 and requires no adjustment.


Dr. Pollock's Modified Agar*
10 grams dried dog food
10 grams amaranth flour
2 grams dextrose or malt extract
9.5 grams agar
500 mL distilled water
Sterilize fifteen minutes at 15 psi pressure; final pH is 6.2 and requires no adjustment.

*The above formula is a modification of one first used by the late Dr. Stephen H. Pollock, discoverer of the extremely rare Psilocybe tampanensis, Psilocybe wassoniorum, and ethnomycologist par excellence.

Tips

*The flask or bottle in which the medium is sterilized should never be more than 2/3 full in order to avoid boilover.

*Plug the flask or bottle with non-absorbent cotton and cover with aluminum foil to help prevent entry of external contaminants.

*Remove the medium as soon as the pressure reaches "0."
Oversterilization or prolonged heating will change the composition of the medium.
Sugars such as dextrose or malt can "caramelize," resulting in a medium that can inhibit mycelial growth and encourage sectors (mutations).
Excessive heating of medium can also cause a drop in pH, resulting in a more acid medium.
It is possible to destroy completely the gelling properties of agar by prolonged heating, and this destruction is hastened as the acidity increases.

*For long-term health and maintenance of sacred strains, alternate any two of the above media.
This will help prevent senescence, which can occur when cultures are grown on one medium only.
Store strains at 35° - 40°F;
transfer every six months.
In this manner, sacred strains can be maintained for years.

*Never compromise the integrity of your strain library. Strains showing even a hint of senescence should be removed from the collection.

Required Reading
Difco Manual Tenth Edition. (First Edition published in 1927.) Difco Laboratories, Detroit, MI (1984).