Projects / Programmes
NUTRITION AND ECOLOGY OF GASTROINTESTINAL TRACT
January 1, 2009
- December 31, 2013
| Code |
Science |
Field |
Subfield |
| 4.02.00 |
Biotechnical sciences |
Animal production |
|
| 4.06.00 |
Biotechnical sciences |
Biotechnology |
|
| Code |
Science |
Field |
| B420 |
Biomedical sciences |
Nutrition |
| Code |
Science |
Field |
| 4.02 |
Agricultural and Veterinary Sciences |
Animal and Dairy science |
nutrition, feed, environment, functional food, health, oxidative stress, probiotics, prebiotics, microbiology, bacteriocins, gastrointestinal tract, selection criteria, markers, identification, classification, biotechnology
Researchers (46)
Organisations (2)
Abstract
Nutrition is an important factor in maintaining organism in good health condition. A new concept in searching for optimal food was introduced designated as functional food. Original definition stating "Food can be labeled as functional when its beneficial effect on one or more target function in the body, beyond satisfying traditional nutrient requirements can be sufficiently demonstrated by evidence", requires establishement of new objectives of research and developmental nature. Study of mechanisms and searching for appropriate markers on molecular and immunological level which enable satisfactory measurement of effects of food or feed, are basic approaches in progress of this new scientific area.
Reasons for development of modern civilisation diseases which can be defined from nutrition-medical point of view can be classified into two groups, the first comprising energetically and compositionally non-equilibrated nutrition, and the latter resulting in disturbed microbial balance of the gut. Normal gut microflora has at least three important roles: it reduces the possibility of infections with pathogenic bacteria, it stimulates maturation of gut mucosal immunological system and development of immune tolerance to ubiquitous antigens. Discovering roles of microorganisms in interactions with host organisms and host itself, is one of the key steps towards understanding the function of the human and/or animal gastrointestinal tract ecosystems. Different in vitro, ex vivo and in vivo methods and different animal models will be applied to carry out the proposed research. Nutrition studies will be performed on domestic and laboratory animals, via monitoring of feed intake and quantitative excrement of substances with urine and faeces, via monitoring of metabolic parameters and investigating of nutritional factors by different markers such as malonaldehyde (MDA) in plasma, in urine, in feeed, in animal products and food (HPLC), via level of DNA damage in the cells (comet test), concentration of E-vitamine (alpha-, beta plus gama-, delta- tocopherol/HPLC), overall antioxidative status of blood serum and glutathion peroxidase activity in enterocytes. In addition to conventional analysis of feed and food, determination of macro- and micro-minerals concentration (atomic absorption spectrometry) and in sacco method for determination of feed digestibility by using fistulated animals, the conditions and microbial fermentation in particular parts of the gut will be studied by determination of concentrations of short chain fatty acids (gas chromatography), ATP, ammonia, of intestinal content viscosity and fermentability (in vitro gas-tests). Besides traditional microbiological methods for isolation and cultivation of microaerophilic and strictly anaerobic bacteria in anaerobic chambers, a wide range of molecular and genetic methods will be used to study structure and population dynamics of microbial community.
Objectives: study of mechanisms and new approaches in feeding, enabling the production of functional food of animal origin, finding out the effects of alternative feed additives (plant extracts, fibrinolytic enzymes) and selected probiotics and prebiotics on the composition of microbial population in the gut of domestic animals or humans and in the systems simulating these ecosystems, selection of markers for measurement of influences of feed, nutrients, pre-, probiotics and other bioactive substances in organism and development of toxicological, genotoxicological and immunological methods for tracing of their positive and negative effects.
Significance for science
Research of the effects of diet on the host organism,on their microbiota and studies of interactions among microorganisms in the gut demanded the development and implementation of molecular, genetic, genomic and proteomic methods that will be useful for the global scientific public. Among other achievements, we have, in collaboration with the Swiss investigators demonstrated the usefulness of transcriptomic analysis of blood cells (mice) as the source of biomarkers to determine the influence of probiotics on the infection, including subclinical, in cooperation with the Czech researchers introduced a method for extracting DNA from fecal and other samples which is based on the use of hydrophilic magnetic beads P(HEMA-co-GMA); improved a Comet assay to evaluate the toxicity and genotoxicity, which was upgraded on the cell line HepG2 liver cells with the use of enzymes FPG (formamidopirimidin glycosylase) and EndoIII (endonuclease III) and introduced the use of a model eukaryotic micro-organism Tetrahymena thermophila; optimized real-time PCR method for investigation of the intestinal mucosal microbiota; introduced the PMA-real-time PCR method for the selective determination of intact bacteria in probiotic products with freeze-dried or microencapsulated microorganisms; tested three dimensional in vitro model of intestinal epithelium, which comprises dendritic cells derived from human monocytes from peripheral blood, human intestinal epithelial cells and probiotic bacteria. Improved methods for the analysis of probiotic products and for genotoxic tests also contribute to EU efforts to standardize and legitimize the methods in EU and replace the use of laboratory animals with cell lines and single-cell organisms. Research of feces, intestinal mucosa, human milk, colostrum, meconium, rumen.. have brought important insights about the diversity of microbial communities that inhabit the gut of various domestic or laboratory animals and humans. Knowledge of the microbiota of different groups of people ( vegetarians, newborns, patients with chronic intestinal diseases) will be useful for the construction of new dietary strategies and preventive measures for the successful fight against various health problems affecting increasing number of humans. The results on the mode of action of natural compounds, particularly plant extracts in various important processes involved in antioxidative defense, obtained in vivo in various animal models, are particularly topical. Due to the difficulties of their implementation there are very few publication reporting in vivo studies in the scientific literature as opposed to in vitro studies. The recognition of the synergistic action of the various groups of antioxidants, soluble in water and fats. The latter affect the health of animals, feeding efficiency (the effect on rumen bacteria and degradability and digestibility of dry matter) and reduce environmental pollution. The latter is important from a global perspective, as the greenhouse gas emissions, mainly from cattle production present serious global ecological problem. Also the discovery of new microorganisms with probiotic potential and demonstration of the mechanisms of their action on the host, such as demonstration of the safety and protective ability of Lb. gasseri K7 in the C57BL/6J mouse model infected with enterohaemorrhagic E. coli O157:H7, testing the safety and anti-inflammatory activity of commensal bacteria from the intestinal mucosa and study of the mechanisms of transmission of lactobacilli (Lb. gasseri K7, Lb . rhamnosus GG) from the intestine into the mammary gland, is interesting at the international level. Today's requirements for probiotic microorganisms include detailed knowledge of the positive and negative characteristics of such microorganisms, mechanisms of their survival and activity in the gut environment and all possible interactions, that they may encounter in with other microorganisms or with host cells and tissues.
Significance for the country
Among the objectives that have been achieved by carrying out the research program Nutrition and microbial ecology of gastrointestinal tract it is worth mentioning first of all The support of the educational process at the first and second cycle of Bologna study programs and at the doctoral level, in accordance with the mission of the institution to which the programme group belongs. So we could directly transferred new developments in this field to the undergraduate academic study programs (Food Science and Nutrition, Biotechnology, Microbiology, Agriculture – Animal production), master study programs (Food Science, Nutrition, Animal Science, Biotechnology, Microbiology), as well as to the students of interdisciplinary PhD programs in Biosciences, Biomedicine and Environmental Protection. The production and supply of safe food, where the results of of this research program group can be assigned, remains among the most important areas of research in Slovenia and in Europe in general in the coming years. The production of safe food is based on the healthy resources and should be implemented in the paradigm of sustainable production. The research team has focused on both aspect, as we tested the efficacy and safety of natural bioactive compounds in the diet of humans and animals, such as natural nutritional feed additives ( wood extracts , natural resources of vitamin E , mushrooms, olive leaves..) and natural probiotics. A part of program which addressed the impact of nutrition of pregnant women and mothers on the gastrointestinal microbiota of children and consequently on their long-term health, has contributed and will contribute to greater awareness, better nutrition, and consequently improving the health status of the population of Slovenia. Along with our partners from industry, we already started with the introduction of new knowledge and methods into the cutting-edge technologies of forage production, management of animal nutrition and the production / processing of healthy and safe food, while lesser burden on the environment. Studies carried out with plant extracts, are also interesting for Slovenian manufacturers of herbal extracts, feed producers and breeders of domestic animals as on the basis of the results of our research we came to certain scientific findings that explain the in vivo activity of natural plant extracts as antioxidants in animal nutrition. They also show their potential in the form of feed additives to improve the quality and stability of animal products and open up the possibility of creating and marketing of such functional foods. The research findings related to their use to reduce environmental pollution are also of significant importance. The results obtained may in the future represent a good foundation for the use of suchnatural plant extracts as antioxidants in human nutrition. Very successful is also the transfer of methods and findings reached in the studies of probiotics into application by both the producers as well as the laboratory for probiotics, which operates in the frame of the Institute of dairy science and probiotics from year 2010. This represents an added value to the quality control of probiotic products as well as encourage the development of new probiotic products. All of the above mentioned is ultimately important to ensure the integrity, quality and competitiveness of Slovenian products and thus the competitiveness of agriculture and agri-food industry. During the implementation of the program it was confirmed that the nutrition issues require complex internal integration of research and development work (R & D), where complementary knowledge of various science and technology is indispensable, and was ensured in our program team.
Most important scientific results
Annual report
2009,
2010,
2011,
2012,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2009,
2010,
2011,
2012,
final report,
complete report on dLib.si
