**4.1 Probiotic application in diseases related to digestive enzyme deficiencies**

Sucrase deficiency, also known as sucrase-isomaltase deficiency, is the most common disaccharidase deficiency in human. It is a genetic disorder and causes to malabsorption of sucrose in diet and consequently to accumulation of hydrogen in the colon, swelling, diarrhea and abdominal cramps (Rolfe, 2000). *Saccharomyces cerevisiae* expresses significant sucrase and some isomaltase activity, and it has been proposed to improve malabsorption in patients with sucrase-isomaltase deficiency (Harms et al., 1987). Similarly Treem et al. (1993) have reported that the liquid preparation which is a by-product of the manufacture of baker's yeast reduced breath hydrogen excretion in patients with congenital sucraseisomaltase deficiency that were given a sucrose load and allowed most patients to consume a sucrose-containing diet.

#### **4.2 Lactase deficiency**

Lactase insufficiency means that the concentration of the lactose cleaving enzyme βgalactosidase, also called lactase, in the brush border membrane of the mucosa of the small intestine is too small. Lactase deficiency is a very common condition characterized with lactose malabsorption in the intestinal mucosa. High concentrations of lactase enzyme are physiologically present in neonates. In the post weaning period, an irreversible reduction of its activity occurs in human (Montalto et al., 2006), and in mammalian animal species (Batchelor et al., 2011). Secondary lactase deficiency can be seen any condition that damages the small intestinal epithelial cells or significantly increases the gastrointestinal transit time. Thus, secondary hypolactasia is transient and reversible (Montalto et al., 2006).

free animals. It has been indicated that the bacterial status altered preferentially the exocrine pancreatic function. The specific activities of amylase, trypsin and carboxypeptidase-A were lower in germ-free than in conventional rats (Lhoste et al., 1996). How microorganisms in digestive tract affect secretion of pancreatic enzymes has not been determined. However hormones which stimulate enzyme secretion in pancreas such as enteroglucagon, gastrin or pancreatic polypeptide have been reported to be lower in germ-free animals compared to conventional animals (Goodlad et al., 1989). Decreased pancreatic enzymes in germ-free animals may be explained by this report. Moreover the cecal micro flora may also affect the pancreas via its metabolites. In fact, SCFA can stimulate amylase release from the rat

Matur et al. (2007) have been reported that chymotrypsin levels decreased but amylase, lipase and trypsin levels did not changed in pancreas of broiler chicks which were supplemented with *Enterrococcius facium* NCIMB10415. In addition, intestinal tract enzyme activities were reported to be lower in animals supplemented with probiotics than those of control animals in the same study. The researchers have suggested that the relevant probiotics may affect the biosynthesis of pancreatic enzymes or their secretion to small intestines, although the mechanism underlying this effect has not been fully

Microorganisms in digestive tract may also affect digestive enzyme activities indirectly. Drouault et al. (2002) have reported that *Lactobacillus lactis* produces lipase and this lipase

Sucrase deficiency, also known as sucrase-isomaltase deficiency, is the most common disaccharidase deficiency in human. It is a genetic disorder and causes to malabsorption of sucrose in diet and consequently to accumulation of hydrogen in the colon, swelling, diarrhea and abdominal cramps (Rolfe, 2000). *Saccharomyces cerevisiae* expresses significant sucrase and some isomaltase activity, and it has been proposed to improve malabsorption in patients with sucrase-isomaltase deficiency (Harms et al., 1987). Similarly Treem et al. (1993) have reported that the liquid preparation which is a by-product of the manufacture of baker's yeast reduced breath hydrogen excretion in patients with congenital sucraseisomaltase deficiency that were given a sucrose load and allowed most patients to consume

Lactase insufficiency means that the concentration of the lactose cleaving enzyme βgalactosidase, also called lactase, in the brush border membrane of the mucosa of the small intestine is too small. Lactase deficiency is a very common condition characterized with lactose malabsorption in the intestinal mucosa. High concentrations of lactase enzyme are physiologically present in neonates. In the post weaning period, an irreversible reduction of its activity occurs in human (Montalto et al., 2006), and in mammalian animal species (Batchelor et al., 2011). Secondary lactase deficiency can be seen any condition that damages the small intestinal epithelial cells or significantly increases the gastrointestinal transit time.

Thus, secondary hypolactasia is transient and reversible (Montalto et al., 2006).

**4.1 Probiotic application in diseases related to digestive enzyme deficiencies** 

pancreas directly (Ohbo et al., 1996).

ameliorated steatorrhea in pigs fed on high lipid meal.

elucidated yet.

a sucrose-containing diet.

**4.2 Lactase deficiency** 

It has been observed that patients with lactose maldigestion had higher lactose tolerance when eating fermented dairy products such as yogurt and could easily digest them compared to milk. There are two mechanisms lying beneath this situation. First, βgalactosidase is released from bacteria in yogurt after digested by bile acids. Second, delaying gastric emptying and slowing intestinal transit times prolong the action of residual β-galactosidase in the small intestine and decrease the osmotic load of the lactose (Marteau et al., 2001). Ojetti et al. (2010) were investigated hydrogen breath excretion and gastrointestinal symptoms as indicators of lactose intolerance in patients. They have reported that hydrogen excretion decreased and clinical symptoms improved in the group given *Lactobacillus reuteri* compared to those of placebo group. De Vrese et al. (2001) tested whether live bacteria in the fermented or non-fermented milk product are a prerequisite for enhanced lactose cleavage by microbial β-galactosidase. They found that lactose digestion in lactose malabsorbers and gastrointestinal well-being can be significantly improved if a milk product contains active microbial β-galactosidase. The bacteria need not to be alive but intact cell walls are required to act as a mechanical protection of the enzyme during gastric passage.
