Sugar and Salt Tolerance of Clostridium pasteurianum and Some Related Anaerobes

Abstract

C. pasteurianum proved to be more tolerant of sugars and salts than the other cultures tested. Osmotic pressure appeared to be the limiting factor for growth in the case of sugars but not of salts. Tolerance of sucrose and sodium chloride was decreased with decrease in pH but, in part, this effect may have been due to Eh. Temperature had little effect on tolerance of sucrose, but did affect the tolerance of sodium chloride. In media with vaseline seal a higher tolerance of sodium chloride was apparent than in the same media without seal. Some evidence of adaptation of the cultures to high concentrations of sucrose and sodium chloride was obtained. Within limits, the age of the inoculum did not affect the tolerance of sucrose, but a higher tolerance of sodium chloride was obtained with older inoculum. The data are discussed in relation to spoilage of an acid canned fruit, Ananas comosus (L.) Merrill. Growth of the cultures in sea water Is considered because of the possible role of spore-forming anaerobes in nitrogen fixation in the sea.