Certain fresh fruits, especially those of the citrus group, which includes the lemon, orange, lime and grapefruit, have long enjoyed popularity for their potency in preventing scurvy. This has been shown in recent investigations to be well founded and to depend upon the presence of a specific chemical substance, water-soluble C. Wide differences in the value of different fruits for this purpose have been shown by investigations relating to scurvy. The content of the anti-neuritic substance, water-soluble B, of several fruits has been studied by Osborne and Mendel, and by Byfield, Daniels and Loughlin (30). Their findings indicate that the anti-neuritic value of orange juice is about the same as that of an equal volume of milk. Orange juice to the extent of 55 c.c. per 100 grams of food mixture was not sufficient to furnish the optimal amount of the factor B, but 75 c.c. seemed satisfactory. Lemon juice was comparable in this respect to orange juice. Ten c.c. of juice per day afforded sufficient water-soluble B to support growth at the normal rate when added to an otherwise adequate diet. Grapefruit was also found to contain the anti-neuritic, water-soluble B. McCollum and Simmonds have found orange juice to contain demonstrable amounts of fat-soluble A (31).

Commercial grape juice, and fresh apple juice were found inferior to the citrus fruits as a source of water-soluble B. Pears resemble apples in this respect, but prunes seemed superior to either. The fruit juices tested by Osborne and Mendel did not show appreciable amounts of fat-soluble A (30).