Organisms Commons^™

Proteolytic Enzymes Of Lactic Streptococci And Their Use In Improving Body And Texture Of Direct Acid Cottage Cheese, Gulamnabi Y. Vahora

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Proteolytic activity of Streptococcus cremoris HP, P₂ and AM₂; Streptococcus lactis-C₂, ML₈ and a commercial mixed culture was determined in skimmilk and whey by measuring the increase in Absorbency at 274.5 nm of a pH 4.6 soluble filtrate, following incubation in a 2.5% casein solution. Proteolytic activity, rate of acid production and growth rate decreased in order of C₂, HP, mixed culture, AM₂, ML₈ and P₂ at a regulated pH (6.1 - 6.2) and 32 C. Maximum proteolytic activity for all cultures was found during the stationary …

The Overwintering Of The Fireblight Bacteria Outside Of Living Tissue In Utah, Sherman V. Thomson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this investigation was to determine the sites of overwintering of Erwinia amylovora (Burrill) Winslow et al. outside of living tissue in Utah. Bacterial isolates were taken from the surfaces of blighted twigs and mummified fruits remaining on the tree; also from internal dead tissue of blighted twigs and mummies, and from soil beneath blighted trees. Each isolate was tested for agglutination with antiserum specific for Erwina amylovora, susceptibility to Erwinia amylovora bacteriophage, production of symptoms in pear seedlings and development of bacterial ooze on green pears.

Both virulent and avirulent isolates were taken from all sites tested. …