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A report by Kupchan et al.( 1) of antitumor activity in the leaves of Acer negando L. prompted the testing of Acer saccharinum L. (Aceraceae) for antitumor activity. An Et0H/H20 extract of the leaves of this plant inhibited B16 melanoma in mice, and isolation of the active material was carried out. The separation yielded methyl gallate (methyl-3,4,5-trihydroxy benzoate) as the active compound. Methyl gallate was tested against B16 melanoma in mice following standard protocols (2) yielding T/C values of 188% and 172% at 25 mg/kg, and testing against tumor cells in culture, again following standard protocols (2), gave the following results: B16 melanoma ID50 4.OX 10-5 M, L1210 ID;o 2.2X 10-5 M, and P388 ID50 2.8X 10-5 M. Finally, the compound was tested for inhibition of reverse transcriptase using the assay detailed by Kacian and Spiegelman (4) and was found to be inhibitory with an I50 of 4.80X 10~3 M.Methyl gallate occurs widely in the Aceraceae as well as other plant families. It has previously been reported to inhibit L1210 leukemia in vivo (3). Investigators should be aware that antitumor activity detected in random screening of plants may be due to this compound. The inhibition of reverse transcriptase by this compound is an observation that has not previously been reported. This is also the first report of its

A simple and rapid liquid chromatographic (LC) method for determining ascorbic, dehydroascorbic, isoascorbic, and dehydroisoascorbic acids in mostly single-component food products was evaluated for use in analysis of multicomponent meatbased food products such as TV dinners. Groundbeef samples were used as blanks for repeatability studies. Samples were fortified with 5,10,20, and 40 ppm of mixed standards of ascorbic acid and isoascorbic acid. Means of 12 recoveries at 4 levels of fortification were 102.5 and 83.5%, respectively, for ascorbic acid and isoascorbic acid, with coefficients of variation of 6.7 and 15.2%, respectively. TV dinner products (21 samples) from a local grocery store were analyzed for vitamin C content. Samples prepared with a commercial food processor and a food grinder were compared. The commercial food processor was more capable than the food grinder in producing a homogeneous sample, which is critical to the method.

A gas chromatographic/mass spectrometric (GC/MS) confirmation procedure for 10 phenyl-N-methyl-carbamate insecticides in liver tissue was developed. The extract from liquid chromatography (LC) is purified with a C18 solid-phase extraction cartridge and then derivatized with heptafluorobutyric anhydride; the derivative is injected for analysis by GC/MS with electron ionization and multiple ion monitoring. The identity of the derivative is confirmed by comparison of its retention time and relative intensity data with those of a standard. Liver extracts from the LC procedure containing carbamates at 10 ppb levels were successfully confirmed by this procedure.

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