Naslov
Structural and functional characterization of exopolysaccharides produced by Limosilactobacillus fermentum MC1 isolated from mother’s milk

Autori
Čuljak, Nina ; Bellich, Barbara ; Cescutti, Paola ; Butorac, Katarina ; Novak, Jasna ; Banić, Martina ; Leboš Pavunc, Andreja ; Bendelja, Krešo ; Durgo, Ksenija ; Šušković, Jagoda ; Kos, Blaženka

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of abstracts from "10th International Congress of Food Technologists, Biotechnologists and Nutritionists" / Komes, Draženka ; Vidaček Filipec, Sanja ; Voučko, Bojana ; Šeremet, Danijela ; Marković, Ksenija ; Rumora Samarin, Ivana - Zagreb, 2022, 255-256

Skup
10th International Congress of Food Technologists, Biotechnologists and Nutritionists

Mjesto i datum
Zagreb, Hrvatska, 30.11.2022. - 02.12.2022

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
exopolysaccharides ; lactic acid bacteria ; Limosilactobacillus fermentum ; NMR

Sažetak
Exopolysaccharides (EPS) are extracellular cell structures tightly bound to the cell envelope or loosely excreted in the microenviroment. They consist of linear or branched repeating units of sugars, but may also contain non-carbohydrate substituents. Depending on sugar composition, EPSs are classified as homo-EPS (HoEPS), made of one repeated monosaccharide unit, and hetero-EPS (HeEPS), made of more than one monosaccharide unit. Among microbial polysaccharides, EPS produced by generally regarded as safe (GRAS) lactic acid bacteria (LAB) have various applications. Most commonly, their role is recognized in improving the texture of the fermented food products. Also, their importance as functional molecules has been recently recognized due to the capacity of bifidogenic, and even antitumor, antiulcer, immunomodulating or cholesterol-lowering effects in vivo. The main challenge for large-scale industrial production is increasing the yield of synthesis. The total yield of EPS depends on several factors including producer strain, medium composition, growth conditions such as temperature, pH and incubation time. Therefore, the aim of this research is a structural and functional analysis of the EPS produced by MC1 strain isolated from mother´s milk. EPS-producer showing characteristic „ropy phenotype“ was identified as Limosilactobacillus fermentum MC1 by 16S RNA sequencing. Whole genome sequencing of the MC1 genome following functional annotation by RAST enabled the detection of the eps cluster for EPS biosynthesis. 1H NMR and 2D NMR analysis showed that EPS isolated from L. fermentum MC1 is composed of two structurally different polysaccharides – the main polysaccharide is composed of repeating units of 1, 6 linked galactofuranose with glucose branches on C2 of the galactose residue, while the determination of the structure of the second polysaccharide is still ongoing. L. fermentum MC1 has shown the ability to survive under simulated gastrointestinal tract conditions, as well as the potential to reduce adhesion of Escherichia coli 3014 via competitive exclusion mechanism. Fluorescence microscopy confirmed the adhesion of L. fermentum MC1 to the Caco-2 cell line. Moreover, addition of EPS further increased adhesion to Caco-2 cell line in vitro. Further experiments will be focused on the determination of the role of EPS related to effects of MC1 strain within the probiotic concept.

Izvorni jezik
Engleski

Znanstvena područja
Biotehnologija

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