Eppin has two potential protease inhibitory domains: a whey acid protein or four disulfide core domain and a Kunitz domain. The protein is also reported to have antibacterial activity against Gram‐negative bacteria. Eppin and its whey acid protein and Kunitz domains were expressed in Escherichia coli and their ability to inhibit proteases and kill bacteria compared. The Kunitz domain inhibits elastase (EC 3.4.21.37) to a similar extent as intact eppin, whereas the whey acid protein domain has no such activity. None of these fragments inhibits trypsin (EC 3.4.21.4) or chymotrypsin (EC 3.4.21.1) at the concentrations tested. In a colony forming unit assay, both domains have some antibacterial activity against E. coli, but this was not to the same degree as intact eppin or the two domains together. When bacterial respiratory electron transport was measured using a 2,3‐bis(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide assay, eppin and its domains caused an increase in the rate of respiration. This suggests that the mechanism of cell killing may be partly through the permeablization of the bacterial inner membrane, resulting in uncoupling of respiratory electron transport and consequent collapse of the proton motive force. Thus, we conclude that although both of eppin’s domains are involved in the protein’s antibacterial activity, only the Kunitz domain is required for selective protease inhibition.

Changes in the oil fraction of stored parboiled rice have been followed as criteria of loss in quality. Storage of parboiled rice in the dark at several temperatures permitted a study of rancidification and of nonenzymatic changes in the oil as measured by peroxides, monocarbonyl compounds, and free acids. In open-container storage, values for peroxides, monocarbonyls, and free acids remain low during an induction period, then rise markedly at or just before the time rancid odors appear. Peroxides and monocarbonyls again decrease to low residual values and rancidity disappears. Free acid values remain at the higher level. Original moisture contents of 1 1.4 to 12.5% fall to about 10% at

Radial distribution of the four solubility classes of protein was determined for eight varieties of milled rice. Five consecutive layers of the kernel, totaling

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