results in a higher rate of protein free radicals formation, as already mentioned; (2) lipid hydroperoxide decomposition either as a complex [LOOH-PH] or as LOOM; both decompositions would promote protein free radical formation and subsequent protein polymerization in accordance with the proposed mechanism; the decreases of the PV of the lysozyme-lipid emulsions subjected to freezedrying support this hypothesis.Lysozyme biological activity decreases after treatment with peroxidizing lipids. Previous works (Kanner and Karel, 1976; Funes et al., 1980) have shown a loss of such activity upon treatment with peroxidizing L or their breakdown volatile products. Our inability to detect changes due to freeze-drying-which induces a higher lysozyme polyermization-would indicate that such loss is not associated with cross-linking.Practical consequences of this work are that (1) usual methods to measure lipid oxidation (such as PV and TBA reaction) in lipid-containing systems subjected to freezedrying may show erroneously low values and (2) the freeze-drying process can affect the quality of food systems in which lipid oxidation has already been initiated. LITERATURE CITED AOAC (Association of Official Analytical Chemistry) "Official Methods of Analysis of the Association of Official Analytical

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Concentrations of 0.01-1.0% of a hexane extract of the seed of neem, Azadirachta indica A. Juss., and several of its chromatographic fractions significantly deterred feeding by three species of scale insects, citrus red mites, and woolly whiteflies. An ether extract of the hexane-extracted seed reduced egg deposition by driedfruit beetles, the ether and ethanol extracts repelled adults and larvae of this insect, and the hexane extract repelled only adults.A concentration of 1% of a pentane extract of the nuts of tung, Aleuritesfordii Hemsl., considerably deterred feeding by adult boll weevils; a concentration of 0.1% of an ether extract of the defatted nuts reduced feeding by striped cucumber beetles and plum curculios; and a concentration of 0.2% reduced feeding by spotted cucumber beetles. Also, these extracts, and ethanolic and aqueous extracts as well deterred feeding by larvae of the codling moth and redbanded leafroller.Several polar and nonpolar components of neem seeds and tung nuts appear to be responsible for the antifeedant properties of these plant materials.Crop damage and loss due to feeding by insect larvae and adults is estimated to total billions of dollars each year in the United States alone. It is therefore imperative that safe, biodegradable substitutes for chemical insecticides be discovered. The United States Department of Agriculture has pioneered in chemical and biological research on insect resistance in plants for many years (Schalk & Ratcliffe, 1977) and now has embarked on an intensive program to develop insect feeding deterrents known to occur naturally in many plants growing as weeds or in crops used for food or fiber.Research in this field in our laboratories involves the isolation, identification, and evaluation of a number of insect antifeedants known to be present in the Indian neem tree, Azadiraehta indica A. Juss. (formerly a synonym of Melia azadirachta (L.)), family Meliaceae, and in the fruit of the tung tree, Aleuritesfordii Hemsl., family Euphorbiaceae.

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