Razvoj liofiliziranog probiotičkog mikroinkapsulata s dodatkom L-askorbinske kiseline

master's thesis

• Title (english): Development of a lyophilized probiotic microencapsulate with the addition of L-ascorbic acid
• Author: Vesna Jurić
• Mentor: Jadranka Frece (mentor)
• Committee member: Ksenija Markov (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for General Microbiology and Food Microbiology); Zagreb
• Defense date and country: 2020-09-21, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Do danas su dokumentirani višestruki korisni učinci probiotika na zdravlje domaćina. Iako je tržište preplavljeno probiotičkim proizvodima, nerijetko provedene studije pokazuju da dostupni probiotički sojevi ne zadovoljavaju osnovne probiotičke kriterije. Jedan od glavnih kriterija je visoki stupanj preživljavanja tijekom prolaska kroz gastrointestinalni sustav domaćina kako bi se na ciljanom mjestu ispoljili korisni učinci. S obzirom na to da je nužno da probiotici u što većem broju prežive navedene stresne uvjete, često se koriste tehnike koje štite stanice netoksičnim biopolimerima. Primjer primjene takvog matriksa je mikroinkapsulacija u alginatnom nosaču. Uz navedeno, važno je da se pripravljenim proizvodima maksimalno produlji trajnost pa se koriste tehnike liofilizacije koje omogućavaju dulje skladištenje. Uz osnovne probiotičke karakteristike često su poželjne i određene funkcionalne karakteristike. Primjerice, novija istraživanja potiču konzumaciju proizvoda s visokim antioksidacijskim potencijalom zbog mnogobrojnih korisnih učinaka na zdravlje. U ovom radu, korištenjem tehnika mikroinkapsulacije i liofilizacije odabran je najefikasniji način zaštite odabranih probiotičkih bakterija: Lactobacillus plantarum M2 i Lactobacillus plantarum KO9. Liofilizirani mikroinkapsulati navedenih sojeva pokazali su visok stupanj preživljavanja u simuliranim uvjetima gastrointestinalnog sustava i bili su prikladan nosač L-askorbinske kiseline povećavajući antioksidativni kapacitet pripravka. Određena je bazalna antioksidacijska aktivnost odabranih sojeva bakterija mliječne kiseline izražena kao sposobnost uklanjanja 2,2-difenil-1-pikrilhidrazil (DPPH) radikala. Budući da L-askorbinska kiselina iskazuje potencijalnu antimikrobnu aktivnost, istražen je utjecaj na rast odabranih patogenih bakterija: Salmonella enterica serovar Typhimurium ATCC 27853 , Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 i Listeria monocytogenes ATCC 2356 te je koncentracija od 50 mg mL-1 značajno inhibirala rast navedenih patogena.

Abstract (english)

Multiple beneficial effects of probiotics on hosts health have been documented. Although the market is flooded with probiotic products, studies often show that available probiotic strains do not fulfill probiotic requirements. One of the main criteria is a high survival rate during passage through the hosts gastrointestinal system in order to exert beneficial effects at the target site. Since it is necessary for probiotics to survive these stressful conditions, techniques that protect cells with non-toxic biopolymers are often used. An example of the use of such a matrix is microencapsulation in an alginate carrier. In addition to the above, it is important to extend shelf life, so lyophilization techniques are used in order to enable longer storage. In addition to the basic probiotic characteristics, certain functional characteristics are often desirable. For example, recent studies encourage the consumption of products with high antioxidant potential due to the many beneficial health effects. In this paper, using the techniques of microencapsulation and lyophilization, the most effective way of protection of selected probiotic bacteria was selected: Lactobacillus plantarum M2 and Lactobacillus plantarum KO9. Lyophilized microencapsules of these strains showed a high survival rate in simulated conditions of the gastrointestinal system and were a suitable carrier of L-ascorbic acid increasing the antioxidant capacity of the composition. The basal antioxidant activity of selected strains of lactic acid bacteria expressed as the ability to remove 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals was determined. Since L-ascorbic acid exhibits potential antimicrobial activity, the influence on the growth of selected pathogenic bacteria: Salmonella enterica serovar Typhimurium ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and Listeria monocytogenes ATCC 2356 was investigated and the concentration of 50 mg mL-1 significantly inhibited the growth of these pathogens.

• Keywords: probiotici; mikroinkapsulacija; liofilizacija; L-askorbinska kiselina
• Keywords (english): probiotics; microencapsulation; lyophilization; L-ascorbic acid
• Language: croatian
• URN:NBN: urn:nbn:hr:159:149164
• Study programme: Title: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra nutricionizma (magistar/magistra nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-01-25 12:09:07