Innovación, Investigación y SaludJul. 23, 2018
Columna destaca los principales beneficios de los probióticos a la salud humana
The beneficial effects of dahi, yoghurt, kefir, koumiss etc. on health are well known. These can be defined as live microbial food supplements, which beneficially influence the health of the host by improving its intestinal microbial balance. The historical association of probiotics with these fermented milk products stands true even today. Probiotic term is derived from a Greek word meaning ‘for life’. Probiotics are the live microorganisms which when ingested in sufficient quantity exert a positive effect on health in addition to traditional nutritional effects. The following microorganisms have been considered as human probiotics:
I. Lactobacillus species: L. acidophilus, L. amylovorus, L. brevis, L. casei, L. casei subsp. rhamnosus (lactobacillus GG), L. caucasicus, L. crispatus, L. delbrueckii subsp. bulgaricus (L. bulgaricus), L. fermentum (L. fermenti), L .gasseri, L. helveticus, L. johnsonii, L. lactis, L. leichmannii, L. paracasei, L. plantarum, L. reuteri, L. rhamnosus.
II. Bifidobacterim species: B. adolescentis, B. bifidum, B. breve, B. infantis, B. lactis (B. animalis), B. licheniformis, B. longum.
III. Other lactis acid bacteria: Enterococcus faecium, Lactococcus lactis, Leuconostoc mesenteroides, Pediococcus acidilactici, Streptococcus thermophilus.
IV. Non lactic acid bacteria: Bacillus subtilis, Escherichia coli strain nissle, Saccharomyces boulardii, S. cerevisiae.
An alternative approach for using the probiotics is the use of prebiotics. A prebiotics is a nondigestible food ingredient that beneficially affects the host by selectively stimulating the growth and/ or activity of one or a limited number of bacteria in the colon, that have potential to improve host health. The third approach is use of symbiotics, which have been defined as a mixture of probiotics, which beneficially affects the host by improving the survival and implantation of live microbial supplements in the gastrointestinal tract.
Due to indiscriminate use of antibiotics, a number of problems like antibiotic resistance, negative side effects and allergic reaction arise. This needs a suitable alternative to it; probiotics serve the purpose with ease and efficiency. All intestinal bacteria exist in dynamic balance with one another, but this balance may be disturbed in certain conditions like prolonged diseases, deprivation from food and water, travel by air, antibiotic and radiation therapy etc. This disturbance can be overcome by consuming fermented milk products containing probiotics. They affect the intestinal microflora in various ways. First, the constituents of products provide nutrients such as microsugars, breakdown product of K-casein etc., which support the growth of Bifidus type of intestinal microflora. Secondly some constituents like oxidation product of thiocyanate may also have antibacterial effect on some species of microflora. Thirdly many of the milk constituents promote the secretion of digestive enzymes and stimulate the peristaltic action of digestive tract, thereby affecting some specific bacteria. Finally, lactic acid bacteria (LAB) may become established within the digestive tract, thus affecting microbial balance of intestine (Sabiki and Mathur, 1997).
Most of the bacteria that are ingested die, when they reach the acid conditions of stomach. For a beneficial bacterium to be classified as a probiotic, it must be resistant to gastric, bile and pancreatic juices to reach the colon alive. The probiotics when attached to the wall of intestine increase the number of beneficial bacteria and fight against harmful bacteria thus maintaining a balance between the beneficial and harmful bacteria by following mechanisms:
- Production of inhibitory substances.
- Blocking of adhesion sites by competitive inhibition.
- Competition for nutrients otherwise consumed by pathogenic microorganisms.
- Stimulation of immunity.