. Bulletin of the Department of Agriculture. Agriculture; Agriculture. SAP-STAIN, MOLD, AND DECAY IN GREEN WOOD. vegetables, cereals, mushrooms, and various soft plant tissues are brought about through the agency of certain oxidizing ferments, the oxidases and the peroxidases (Aso 1^2^ S\ Clark, <S, 9\ Kastle, 27). These ferments are sometimes distinguished by the production of a strong blue color in a tincture of guaiacum v^^hen used in the presence of oxygen or hydrogen peroxid (Haas and Hill, 16, p. 383). Bailey {5) states that the ac- tivity of these oxidizing enzyms increases with
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. SAP-STAIN, MOLD, AND DECAY IN GREEN WOOD. vegetables, cereals, mushrooms, and various soft plant tissues are brought about through the agency of certain oxidizing ferments, the oxidases and the peroxidases (Aso 1^2^ S\ Clark, <S, 9\ Kastle, 27). These ferments are sometimes distinguished by the production of a strong blue color in a tincture of guaiacum v^^hen used in the presence of oxygen or hydrogen peroxid (Haas and Hill, 16, p. 383). Bailey {5) states that the ac- tivity of these oxidizing enzyms increases with the rise in tem- perature to a certain point, which may be called the opti- mum, and then decreases as the temperature is raised above this point. In almost every case, ac- cording to the same authority, the activity is entirely destroyed before a temperature of 100° C. (212° F.) is reached. He also states that the activity of these oxidizing ferments is dimin- ished or destroyed by certain antiseptics and by other chemi- cal substances. According to Aso {1,-2), such substances as tannin, sodium fluorid, and so- dium silicofluorid, interfere with the color reactions nor- mally produced by oxidases. Bailey (5) notes the strong similarity existing between the oxidizing activities of these en- zyms and the chemical reactions responsible for certain kinds of sap-stain, namely, post-mortem oxidation with change of color produced by solutions in con- tact with the air and the similar variations in the activity of the discoloring agency in relation to variations in temperature. If discolorations in sapwood are due to the activity of oxidizing enzyms, which, as has been shown, are rendered inactive by exposure to a temperature of 100° C. (212° F.), a logical prophylactic measure would be the submersion of timber in boiling water. Bailey (5), during the spring of 1910, performed certain dipping Fig. 1.—Board of sugar pine, showing chemical stain. The unstained area
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