No public access
master's thesis
Effect of gliadin fractions on growth of probiotic bacteria genus Lactobacillus in vitro

Marina Ožbolt (2016)
Sveučilište u Rijeci
Odjel za biotehnologiju
Metadata
TitleUtjecaj glijadinskih frakcija na rast probiotičkih bakterija iz roda Lactobacillus u in vitro uvjetima
AuthorMarina Ožbolt
Mentor(s)Roberto Antolović (thesis advisor)
Abstract
Sastav humanog mikrobioma odraz je zdravlja pojedinca. Dokazano je da se kod ljudi s alergijama na hranu u njihovom mikrobiomu javlja neravnoteža između korisnih i štetnih bakterija. Probiotički pripravci se sve češće koriste ne samo u svrhu održavanja normalne mikroflore gastrointestinalnog sustava, već kao bioterapeutici u prevenciji i liječenju bolesti. Nepotpuna razgradnja glijadina u gastrointestinalnom traktu dovodi do pojave toksičnih peptida koji mogu aktivirati imunosni odgovor organizma, međutim, dokazano je da upravo probiotički pripravci mogu pomoći u sprječavanju njihovih štetnih učinaka. Kao potencijalna terapija posebice se ističu probiotički pripravci koji sadrže bakterije roda Lactobacillus. U ovom radu je istražen utjecaj glijadina na proliferaciju sedam Lactobacillus sojeva proučavanjem dvaju parametara – brzine rasta i duljine trajanja njihove lag faze u in vitro uvjetima. Bilo je potrebno izabrati najprikladnije otapalo za otapanje glijadina, a rezultati su pokazali da glijadin ima najveću topljivost u otopini 2% natrijeva klorida pH 6,2, a zatim u otopini 70% etanola u 50 mM Tris/HCl pH 7,2. Najmanje se otopio u otopini 70% etanola pH 6,6. Lactobacillus sojevi tretirani su glijadinom otopljenim u 70%-tnoj otopini etanola u 50 mM Tris/HCl te glijadinom otopljenim u otopini 2% natrijeva klorida. Rezultati pokazuju da glijadin u otopini 70% etanola u 50 mM Tris/HCl potiče proliferaciju nekih ispitivanih bakterija (L. helveticus XA/2, L. plantarum IIA/5, L. rhamnosus GG i L. paracasei spp. paracasei 1753), dok nema značajnog utjecaja na proliferaciju ostalih ispitivanih bakterija (L. acidophilus 145, L. casei VIIB/6, L. paracasei VIIB5). Rezultati pokusa s glijadinom otopljenim u otopini 2% natrijeva klorida, pokazuju da glijadin potiče proliferaciju bakterija L. helveticus XA/2 i L. plantarum IIA/5, dok nema značajnog utjecaja na proliferaciju ostalih ispitivanih bakterija (L. acidophilus 145, L. rhamnosus GG, L. casei VIIB/6, L. paracasei VIIB5, L. paracasei spp. paracasei 1753). Brzina rasta L. helveticus XA/2 i L. plantarum IIA/5 rasla je s porastom koncentracije glijadina u otopini 2% NaCl-a, no produljivala se i lag faza jer je navedenim bakterijama bilo potrebno dulje vrijeme za prilagodbu na nove uvjete.
Keywordsgliadin disorders of the gastrointestinal tract Lactobacillus proliferation
Parallel title (English)Effect of gliadin fractions on growth of probiotic bacteria genus Lactobacillus in vitro
Committee MembersRoberto Antolović (committee chairperson)
Sandra Kraljević Pavelić (committee member)
Mladenka Malenica Staver (committee member)
GranterSveučilište u Rijeci
Lower level organizational unitsOdjel za biotehnologiju
PlaceRijeka
StateCroatia
Scientific field, discipline, subdisciplineBIOTECHNICAL SCIENCES
Biotechnology
Study programme typeuniversity
Study levelgraduate
Study programmeBiotechnology in medicine
Academic title abbreviationmag. biotech. in med.
Genremaster's thesis
Language Croatian
Defense date2016-09-16
Parallel abstract (English)
The composition of the human microbiome significantly influences the human health. It has been shown that imbalance between good (useful) and harmful bacteria is common in people who are suffering from food allergies. For that reason, use of probiotic supplements is increasing and they are broadly used not only to maintain the normal flora of the gastrointestinal system, but also as biotherapeutics in prevention and treatment of different gastrointestinal disorders. Incomplete digestion of gliadin in the gastrointestinal tract leads to formation of toxic peptides which can cause immune response in individuals. However, studies have shown that administration of probiotic supplements may prevent or mitigate adverse effects of these peptides. Among probiotic supplements, ones containing probiotic bacteria of genus Lactobacillus are standing out a potential therapy. This study shows effects of gliadin on proliferation of seven Lactobacillus strains, in vitro, studying two parameters - the growth rate and the lag phase. It was necessary to choose the most suitable solvent for dissolving the gliadin and the results showed that gliadin has the highest solubility in a solution of 2% sodium chloride pH 6,2, and then in a solution of 70 % ethanol in 50 mM Tris/HCl pH 7,2. Gliadine was least dissolved in 70 % ethanol solution pH 6,6. Lactobacillus strains were treated with gliadin disolved in solution of 70% ethanol in 50 mM Tris/HCl and with gliadin disolved in solution of 2% sodium chloridewhich was use din two different experiments. Results show that gliadin in solution of 70% ethanol in 50 mM Tris/HCl induced proliferation of tested bacteria (L. helveticus XA/2, L. plantarum II/5, L. rhamnosus GG and L. paracasei spp. paracasei 1753) or it had no significant effect on growth of other tested bacteria (L. acidophilus 145, L. casei VIIB/6, L. paracasei VIIB5). Results of the experiment with gliadin dissolved in 2% sodium chloride show that gliadin stimulated proliferation of L. helveticus XA/2 and L. plantarum II/5, but didn't have a significant effect on growth of other tested bacteria (L. acidophilus 145, L. rhamnosus GG, L. casei VIIB/6, L. paracasei VIIB5, L. paracasei spp. paracasei 1753). The growth rate of L. helveticus XA/2 and L. plantarum IIA/5 was higher with increasing concentration of gliadin in solution of 2% NaCl, but the lag fase was also longer because the bacteria needed more time to adjust to new conditions.
Parallel keywords (Croatian)glijadin bolesti gastrointestinalnog sustava Lactobacillus proliferacija
Resource typetext
Access conditionNo public access
ProjectProject funder: Sveučilište u Rijeci
Project jurisdiction: HR
Project name: Priprema uzoraka za metaboličku, proteomičku i glikomičku analizu
Project ID: 13.11.1.2.03.
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:193:975433
CommitterIvana Dorotić