Studies on a Growth Stimulant From Corn Steep Using Lactobacillus Casei

Abstract

Corn steep liquor has found considerable use as a source of nutrients for certain molds and bacteria used in industrial fermentations (Moyer and Coghill, 1946; Moyer et al., 1940; Stubbs et al., 1940; Wells et al., 1939). Liggett and Koffler (1948) reported that corn steep liquor alone contains sufficient nutrients for the growth and development of many bacteria, and Winsten and Eigen (1949) and Picken and Bauriedel (1950) found that corn steep contained a growth stimulant for Lactobacillus leichmannii strain 313. Kennedy and Speck (1954) reported that corn steep contains a growth stimulant(s) for a number of lactic acid bacteria when grown in either milk or synthetic media that are supposedly complete nutritionally. Platt (1952) studied the properties of the corn steep constituent(s) which stimulated the growth of lactic acid bacteria and found the factor(s) to be stable to 120 C for 60 minutes at pH 2.0 and 4.0, but slightly less stable at higher pH values. The activity of the factor(s) was not affected by the action of pepsin, papain, pancreatin, erepsin, taka-diastase, or salivary amylase. The factor(s) was found to be very water soluble but very slightly soluble in organic solvents. It was dialyzable, not steam volatile, and was adsorbed on activated carbons, cellulose, and diatomaceous earths. This report concerns further observations on asay and purification techniques for the corn steep factor(s), and its relation to other growth stimulants.

Dl-Forming Lactic Acid Bacteria

“…We can not conclude from these results, however, that the maximum growth of active lactic acid formers is achieved in the presence of comparatively small amounts of nicotinic acid. It is more likely that their maximum growth is controlled by some other factor, as was shown by Kennedy et al (7) . 3The optical properties of lactic acid and the racemiase activity of cells formed in nicotinic acid-restricted medium.…”

Detection by Warburg manometry of compounds stimulatory to lactic acid bacteria

“…The growth-promoting effect of extracts from plants and microorganisms has been measured in a number of ways, e.g. turbidimetrically (Sandine et al 1956;Kennedy et al 1955), by measuring lactic acid production titrimetrically (Selby Smith et al 1975) or by measuring pH shifts (Koburger et al 1963;Gilliland & Speck, 1969), counting of bacterial numbers (Nath & Wagner, 1973) and with bioautographical methods (Kennedy et al 1955). In the screening for growth factors, a manometric method has the advantage that small reaction volumes can be used and the course of the reaction can be read periodically without taking samples from the system for measurements of pH or bacterial numbers.…”

AMINO ACID CONTENT OF A PEPTIDE STIMULATORY FOR LACTOBACILLUS CASEI

“…A solution of 0.25 per cent ninhydrin (w/v) in anhydrous acetone (Toennies and Kolb, 1951) was used to detect the resolution of ninhydrin reactive substances present in pancreas extract. The strip was dipped in the ninhydrin solution, held in a horizontal position until the liquid was evaporated and then placed in a drying oven at paper chromatographs were detected by the bioautographic technique of Kennedy et al (1955). The bioautograph plates were prepared with a modified medium of Kodicek and Mistry (1952).…”