An appropriate in vitro starch digestion model is necessary to comparatively evaluate the digestibility of starch samples and to help predict the in vivo glycemic responses of starchy foods. In the present study, the effect of trypsin and chymotrypsin on in vitro digestion of rice starch was studies for the first time. Inclusion of the trypsin and chymotrypsin in the digestion protocols, to mor...

The anomalies of enzyme action have frequently been accounted for by the assumption of an intermediate compound between the enzyme and the substrate. I t was shown, however, by Nelson and Hitchcock t that in the case of invertase the experiments could not be accurately calculated on this basis. The writer found with trypsin' that although the effect of varying the substrate concentration could ...

The ability of Yersinia to digest polypectate may be of some value in differentiating Y. enterocolitica and Y. pseudotuberculosis from some of the other fermenting gram-negative bacilli, such as Enterobacter agglomerans, with which they can be confused. Pectolytic activity in Yersinia may also have some teleologic or taxonomic significance about which we do not care to speculate.

About three-quarters of a century ago, Santayana wrote, "Those who cannot remember the past are condemned to repeat it." This somber dictum is splendidly illustrated by the history of the study of protein digestion and absorption over the same three-quarters of a century (12,13). This chapter begins with a summary of this history, since it provides a deeper understanding of the principles invol...

A sea anemone, normally a passive-looking animal, reacts to suitable food,.. stuffs by a series of fairly complicated activities. When its tentacles encounter solid food there is, first of all, a discharge of cnidae, which poison living prey and adhere to the food mass. These cnidae are independent effectors, responding directly to external excitation (Pantin, 1942). Next, the tentacles clasp t...

ing the installation of anaerobic digestion systems and the equipment necessary to generate electricity from the methane produced and collected by these systems. There are several reasons these systems are being considered: decreasing onfarm energy costs by using methane to generate electricity; mitigating odor problems on livestock operations; and improving the handling of manure nutrients and...

A knowledge of the sites of digestion and extent of digestion of nutrients is essential for the formulation of diets to meet the requirements of pigs. This is of particular importance for young pigs, where there is rapid gastrointestinal development, but it must be taken into consideration in formulating diets from birth, through pregnancy and lactation. The following four papers discuss the de...

Sample preparation is the critical step of any analytical protocol, and involves steps from simple dilution to partial or total digestion. The present review focuses on wet digestion methods used for solid and liquid sample pre-treatment. The methods include wet decomposition and dissolution of the organic and inorganic samples, in open and closed systems, using thermal and radiant (ultraviolet...

That some species of Clostridia elaborate proteolytic enzymes has been known since the earliest days of bacteriology (1-3). Indeed, it was soon realized that such organisms were unusually active in this respect and played a major part in the natural processes of putrefaction (4-8). Yet neither these studies nor the much more detailed chemical investigations undertaken during and shortly after W...

Concept Outline 51.1 Animals employ a digestive system to prepare food for assimilation by cells. Types of Digestive Systems. Some invertebrates have a gastrovascular cavity, but vertebrates have a digestive tract that chemically digests and absorbs the food. Vertebrate Digestive Systems. The different regions of the gastrointestinal tract are adapted for different functions. The Mouth and Teet...