Lactic acid producing bacteria that are capable of improving or maintaining intestinal health and function, including reducing constipation (primarily from the Lactobacillus and Bifidobacterium genera) are termed probiotic bacteria. Dietary supplements with probiotic bacteria as the active ingredient currently enjoy sales of over $700 million annually, and the market growth is approaching 30% annually. The other piece of the probiotic market is probiotic foods, especially yogurt and desserts. This segment of the market is over $1 Billion annually.
The reported health benefits of probiotics include supporting the immune system (inhibiting allergic response and neoplastic growth), treating inflammatory bowel disease, offsetting lactose intolerance, and reducing cholesterol. They are also useful for repopulating the gut after antibiotic therapy. Probiotic growth in the intestinal tract, following ingestion, depends to a large extent on the nutrients present in the patient's diet. Typical human diets are not well suited for probiotics and, given the abundance of and competition from many less fastidious digestive tract bacteria (including pathogenic strains such as clostridium, rotaviruses, pathogenic E. coli and Helicobacter pylori) it can be difficult for probiotics to effectively multiply in vivo. To help correct this problem, manufacturers of probiotic dietary supplements often include prebiotics (nutrient substances that encourage the growth of probiotics in vivo) in their formulations.
Many types of prebiotics are not digested or absorbed in the small intestine but pass into the colon where they stimulate the growth of probiotic bacteria. Fructo-oligosaccharides (FOS) are one type of prebiotic; inulin compounds (which are also oligosaccharides) are another. For these compounds to be effective they must be ingested in relatively large quantities, such as 4-10 grams/day for FOS and 10-14 grams/day for inulin. Probiotics, by comparison, can be effectively administered in milligram quantities, containing 107-1010 colony forming units (cfu). Thus, it is impractical to mix FOS or inulin with probiotics and deliver them in capsules or tablets. Further, such carbohydrate type prebiotics often break down to glucose, in vivo, which enhances growth of non-probiotic bacteria, including pathogenic clostridium. Moreover, FOS can cause flatulence and abdominal pain and some people experience severe allergic reactions to inulin. Therefore, there is a need for a non-carbohydrate prebiotic that can be used at low dosage while effectively stimulating probiotic bacteria.
Although enzymes have been used to generate prebiotics under laboratory conditions followed by subsequent feeding of the preformed prebiotics to achieve probiotic stimulation (see U.S. Pat. Nos. 6,791,015 and 6,730,502), no one has suggested using enzymes to generate these effects in vivo. U.S. Pat. No. 5,817,350 discloses the use of the prebiotic enzymes cellulase, amylase and hemicellulase, for use as dietary supplements, but not use of these enzymes to stimulate administered probiotics. Enzymes which can generate compounds which significantly increase probiotic growth or activity without generating significant amounts of glucose or otherwise stimulating growth of undesirable digestive tract bacteria, would be a significant improvement over existing formulations.
Iso-malto oligosaccharides can be enzymatically digested to simpler sugars by inulinase, which is included in some commercially-available probiotic formulations because it digests linear fructans (inulin). Inulin is known to stimulate bifidobacteria growth. Inulin in diet does not lead to a rise in serum glucose or stimulate insulin secretion, but inulinase digestion generates significant fructose. It is not clear whether fructose would preferentially increase growth of probiotics or of competitive digestive tract bacteria, including pathogenic bacteria.
The product Beano™ includes the enzyme alpha-galactosidase, which can break down polysaccharides and oligosaccharides, including iso-malto oligosaccharides, which are in foods such as legumes (beans and peanuts) and cruciferous vegetables (cauliflower, broccoli, cabbage, brussels sprouts, among others). The enzyme breaks those complex sugars into simpler sugars, making these foods somewhat more digestible, and thereby reducing intestinal gas. Beano does not include any probiotics in its formulation.
The hydrolysis of lactose to glucose and galactose is catalyzed by the enzymes lactase and β-galactosidase. Because β-galactosidase would generate glucose from lactose in the diet, it is not preferred for inclusion in probiotics. Lactobacillus bulgaricus produces beta-galactosidase, and this strain is a probiotic purported to treat lactose intolerance.