Development of functional foods

Abstract

Recent advances in intestinal microbiota research are the background for the appearance of functional foods. Lactic fermentation products are included in the functional foods and classified into 3 groups based on their mechanisms of action: probiotics, prebiotics and biogenics. Probiotics are viable microorganisms, such as lactobacilli and bifidobacteria, that beneficially affect the host by improving the intestinal bacterial balance. Prebiotics are nondigestible food ingredients, such as oligosaccharides and dietary fiber, that beneficially affect the host by selectively stimulating the growth or activities of beneficial intestinal bacteria in the colon and thus improve the health of the hosts. Biogenics are biologically active peptides, including immunopotentiators (biological response modifier: BRM), plant flavonoids, etc. They act directly or indirectly through modulation of intestinal microbiota on the health of the hosts. Thus, functional foods enhance bioregulation such as stresses, appetite and absorption; biodefence, such as immunity and suppression of allergies; prevent diseases, including diarrhea, constipation, cancer, cholesterolemia and diabetes; and suppress aging through immunostimulation as well as suppression of mutagenesis, carcinogenesis, oxidation processes, intestinal putrefaction, and cholesterolemia.

Keywords: functional foods; intestinal bacteria; intestinal bacteriology; intestinal microbiota.

Fig. 1.

Changes in mortality due to selected causes among the Japanese population (Association for Health and Welfare Statistics).

Fig. 2.

Changes in mortality due to malignant tumors in selected sites of among the Japanese (Association for Health and Welfare Statistics).

Fig. 3.

Lifestyle-related diseases and their mutual relationships.

Fig. 4.

Changes in fecal population of conventional mice before and after feeding of cow’s milk and influence of oral incubation of human bifidobacteria on the fecal populations.

Fig. 5.

Effect of fructo-oligosaccharides administration on counts of bifidobacteria in feces of elderly patients.

Fig. 6.

Changes in the intestinal microbiota of volunteers following administration of soybean oligosaccharide extract (SOE) or soybean oligosaccharide extract with 6 × 10⁹ of Bifidobacterium longum (SOB).

Fig. 7.

Changes in the numbers of organisms in the feces of gnotobiotic mice inoculated with various strains.

Fig. 8.

Changes in the survival ratio of mice administered with sour milk or whole milk. ○: Control, ■: Whole milk, ▲: Sour milk.

Fig. 9.

Changes in the intestinal microbiota of mice administered with sour milk or whole milk. ○: Control, Δ: Whole milk, ●: Sour milk.

Fig. 10.

Effect of administration of yogurt or sour milk to mice on proliferation of Ehrlich ascites tumor cells. ●: Control, ○: Yogurt (pasteurized), Δ: Yogurt (not pasteurized), □: Sour milk (pasteurized).

Fig. 11.

Effect of yogurt (130 g/day) intake on fecal flora and fecal metabolites in healthy adults (21–50 years old).

Fig. 12.

Effect of NAN BF (containing 10^8.8 B. lactis, 0.14 g galacto-oligosaccharides and 4 g lactose/200 mL) on fecal flora. Figures in parentheses indicate the rate of detection (%). The rate of detection for bacterial groups without parentheses is 100%. Subjects: 9 healthy children aged 12–31 months.

Fig. 13.

Functional mechanisms of fermented milks (probiotics), lactic fermentation products (biogenics) and oligosaccharides/dietary fiber (prebiotics).

Fig. 14.

Maintenance of bio-homeostasis by lactic fermentation products.

Fig. 15.

Bioregulation by functional foods.