Bifidogenic action of Lactusan

1. 1. In experiments in vitro to study the effect of preparations with lactulose on the growth of bifidobacteria.

1. 1. In experiments in vitro to study the effect of preparations with lactulose on the development of populations of ubiquitous microorganisms.

1. 1. Study of the cytopathogenic effect of drugs with lactulose on a cell culture model.

1. In vitro experiments to study the effect of preparations containing lactulose on the enzymatic activity of lysozyme.

The drugs used in the work:

• "Lactofan";
• "Bifidofan";
• "Lactusan";
• "Laktovit";

pure cultures of microorganisms:

• Bifidobacterium bifidum;
• Staphylococcus aureus;
• Staphylococcus epidermidis;
• Escherichia coli;
• Pseudomonas aeruginosa;
• Bacillus subtilis;
• Bacterium cereus;
• Lactobacillus plantarum;
• bacteria of the genus Proteus;
• Candida albicans;

artificial nutrient media:

• Wednesday Endo;
• meat-peptone agar;
• milk-yolk-salt agar;
• blood agar;
• Blaurock Wednesday;
• Saburo Wednesday;
• meatloaf broth.

The study of the development of microorganism populations was carried out using the methods of quantitative inoculation and the turbidimetric method, the growth rate was assessed by the change in the turbidity of the suspension and the determination of CFU per ml.

We used semi-transplantable cell cultures:

• Hep-2 – human epithelial carcinoma cell culture
• RD, human rhabdomyosarcoma cell culture.

Lysozyme activity was determined by the nephelometric method in relation to the culture of Micrococcus luteus by the method developed by O.V. Bukharin (1992).

RESULTS OF THE STUDY

The studied preparations were added to the culture medium at a concentration of 10 percent, the studied microorganisms were inoculated in the amount of 0.1 ml 2 mld. suspensions of bacteria of certain species, inoculations were incubated at 37С, there were no lactulose preparations in the control samples. The intensity of the development of bacterial populations was estimated by the photonephelometric method according to the degree of change in the turbidity of a 24-hour culture.

The addition of "Bifidofan" to the medium increased the intensity of the development of bifidobacteria to the greatest extent, which may be associated with an increase in the inoculation dose. The turbidity of the suspension increased to 0.96 while the values in the control were 0.41. Along with this, in the presence of "LAKTOFAN", "LAKTUSAN" and "LAKTOVIT", an increase in the intensity of development of the population of bifidobacteria and lactobacilli was observed (the turbidity of the suspension was 0.72, 0.64, 0.83, respectively).

Thus, the lactulose of the studied drugs has the ability to increase the intensity of the development of populations of bifidobacteria and lactobacilli, "Bifidofan" has a more pronounced bifidogenic effect.

It has been established that LAKTOFAN reduces the intensity of the development of the S.aureus population (turbidity index 0.47, in the control - 1.45), microorganisms of the genus Proteus (in the experiment - 0.06, in the control - 0.15), Ps. aeruginosa (in the experiment - 0.1, in the control - 0.15), fungi of the genus Candida (in the experiment - 0.14, in the control - 0.16). Increases the intensity of reproduction of E. coli (in the experiment, the turbidity index is 0.17, in the control - 0.1).

"Bifidofan" increases the intensity of reproduction of Escherichia coli (from 0.1 to 1.2, respectively) and reduces the intensity of the development of populations of staphylococcus, microorganisms of the genus Proteus and fungi of the genus Candida.

"Lactusan" does not change the intensity of development of E. coli and significantly reduces the intensity of growth of fungi of the genus Candida, staphylococci and Proteus.

"LAKTOVIT" increases the development of Escherichia coli (turbidity of the culture - 0.41, in control - 0.18), reduces the growth of staphylococci (0.26 in the experiment, 1.45 - in control), microorganisms of the genus Proteus (in the experiment - 0, 4, in control - 1.01).

Thus, the intensity of the development of opportunistic microorganisms in the presence of the studied lactulose preparations significantly decreases, which may be of practical importance in the directed normalization of the intestinal microflora in dysbacteriosis using these lactulose preparations. The use of these drugs can increase the number of Escherichia coli in the intestine and reduce the intensity of reproduction of pathogenic microorganisms.

The nature of the action was the same in the study of all four drugs:

• when adding drugs to the culture medium, no significant changes in the cell culture monolayer were observed;
• after 24 hours, a change in the color of the medium was observed due to a change in the reaction of the medium to the acid side with the addition of preparations "BIFIDOPHAN" and "LACTOPHAN". Morphological changes in the cell monolayer were not observed.

Thus, lactulose preparations do not have cytopathic and cytotoxic effects.

The lysozyme activity of the commercial drug "lysozyme" was studied in the presence of various concentrations of drugs (5%, 10%, 15%, 20%). It has been established that drugs at a concentration of 5% increase the enzymatic activity of lysozyme. More active in this regard is BIFIDOFAN. Increasing the concentration of drugs to 10-15% does not affect lysozyme activity, increasing the concentration to 20% reduces the activity of the enzyme.

1. 1. Lactulose preparations increase the intensity of the development of the population of bifidobacteria in vitro.

1. 1. Growth and reproduction of the population of lactobacilli in the presence of lactulose preparations increase.

1. 1. Lactulose preparations increase the intensity of reproduction of the E.coli population.

1. 1. In the presence of lactulose preparations, the intensity of development of staphylococci, fungi of the genus Candida, microorganisms of the genus Proteus and Ps.aeruginosa decreases.

1. 1. Lactulose preparations do not have a cytopathic effect.

1. 1. In the presence of lactulose preparations, the enzymatic activity of lysozyme is enhanced, a dose-dependent effect is noted.

1. 1. The activity of drugs is different. A more pronounced bifidogenic effect, an increase in the growth rate of E.coli, suppression of the development of ubiquitous bacteria, and an increase in the enzymatic activity of lysozyme are observed in the preparations "BIFIDOPHAN" and "LAKTOVIT".

1. Preparations "LACTUSAN", "BIFIDOFAN", "LAKTOVIT", "LAKTOFAN" can be used to treat dysbiotic changes in the composition of the microflora of the body, to normalize automicroflora, to enhance the antagonistic activity of representatives of the normal microflora against pathogenic and opportunistic microorganisms, increase nonspecific resistance organism, increasing the activity of lysozyme.

Professor of the Department of Microbiology with Immunology and Virology
Yaroslavl State Medical Academy
Doctor of Medical Sciences,

corresponding member RAE