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Isolation and Redefinition of the Toxic Agent from Cocklebur (Xanthium strumarium)The highly toxic agent responsible for the poisonous properties of cocklebur, a common weed, has been isolated and identified as carboxyatractyloside. The toxin was identified by spectroscopic and chemical comparisons with authentic carboxyatractyloside.Cocklebur plants, Xanthium spp., are widely distributed in the United States and are found in nearly all parts of the world. The plants have become especially noxious in South Africa and Australia. The poisonous properties of cocklebur are found only in seed and very young seedlings that still contain the cotyledon (cotyledon stage) (Marsh and Roe, 1924). Very young cocklebur seedlings, growing

A nondestructive peanut pod maturity classification method, Pod Maturity Profile (PMP), based on visual examination of the color and structural characteristics of pod mesocarp after partial removal of pod exocarp, was used to separate freshly harvested peanut pods into maturity classes. The separations made nondestructively were compared with those made by a method involving the examination of internal pericarp and testa characteristics. The groups separated by the two methods were closely related. In oil from the PMP classes, color decreased, free fatty acid content decreased, iodine value remained approximately constant, and oven stability of the extracted oil increased with increasing maturity. Total oil contents and fatty acid profiles had consistent but more complex relationships with maturity. The data indicate that the PMP method allows consistent and reproducible classification of peanut fruit maturity.

Samples of segregation 3 farmer stock peanuts from the 1980 southeastern United States growing season were analyzed for the presence of cyclopiazonic acid and aflatoxins. Cyclopiazonic acid appeared in 21 of 27 loose-shell kernel fractions at a range of 32 to 6,525 ,ug/kg and in 4 of 21 sound mature kernel fractions at a range of 32 to 130 ,g/kg. Aflatoxins were detected in 26 of 27 looseshell kernel fractions and in 20 of 21 sound mature kernel fractions. Cyclopiazonic acid used at 105 and 210 ,ug/kg to spike peanut samples was recovered at an average rate of 93.3%, with ranges of 89 to 119 and 166 to 221 ,ug/kg, respectively. The minimum detection limit on oxalic acid-impregnated silica gel plates was 26 ng.