Pigment Glands of Cottonseed. III. Distribution and Some Properties of Cottonseed Pigments

Abstract

1. All the gossypol and gossypurpurin of the cottonseed kernel are segregated in the pigment glands, and they constitute the only detectable pigments in the glands of four varieties of seed of Gossypium hirsutum which were examined. 2. The gossypol content of the glands is relatively constant, this pigment constituting up to approximately 50% of the weight of the glands, whereas the gossypurpurin content is relatively low and variable. 3. On the basis of the direct correlation observed between the amounts of glands and of gossypol in the kernels, it is suggested that the gland content is the principal factor which determines the gossypol content of the cottonseed kernel. 4. A yellow pigment has been detected in solution in the oil of the extraglandular tissue of the kernel. This pigment has been obtained free of gossypol, gossypurpurin, and the yellow decomposition product of gossypurpurin. Partial characterization of the extraglandular pigment has shown it to be relatively stable and to differ from every pigment previously detected in cottonseed. 5. On the basis of the distribution and properties of the pigments of cottonseed, methods for their extraction and estimation have been developed.