Macromolecules secreted into the media by a nondifferentiating suspension culture of tobacco cells were found to be composed of protein and polysaccharide, and to account for the viscosity of the media. The concentration, composition, and viscosity of these macromolecules changed significantly with the age of the culture and growth temperature. The concentration changed from 0.02 mg/ml in newly inoculated cultures to over 1 mg/ml in older cultures. The macromolecules contained from 6 to 18% protein and 3 to 4 mumoles hydroxy-proline/mg nitrogen, more than 20 times the level found in whole cells. The macromolecules contained 5 to 25% pectic substances whose carboxyl groups were either methyl esterified or combined with calcium. Arabinose, xylose, glucose, galactose, and mannose were identified in acid hydrolysates of the macromolecules. Peroxidase activity of the macromolecules increased as cultures became older. Peroxidase isoenzyme patterns changed with culture age and growth temperature. The relation of the macromolecules to cell walls and intercellular substances is discussed.

S The conditions for the autolysis of stachyose, raffinose and phytic acid in California small white beans were determined. It was found that initially the beans contain about 3.7% stachyose, 0.4% raffinose and no detectable verbascose. Optimum conditions for autolysis of these sugars are pH 5 and 45–65°C. Approximately 30% of the sugars are hydrolyzed in 9 hr, 50% in 24 hr and 70% in 48 hr. Disappearance of the oligosaccharides is accompanied by corresponding increases in galactose and sucrose. Other changes occur during incubation, including the hydrolysis of phytic acid with the production of inorganic phosphate and inositol. Optimum conditions for the production of inorganic phosphate and inositol are pH 5 and 35–45°C. When fed to rats incubated preparations of beans produced less hydrogen than nonincubated preparations.

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