magistrsko delo
Romana Černe (Avtor), Barbara Jeršek (Recenzent), Bojana Bogovič Matijašić (Mentor)

Povzetek

V zadnjih letih se je ponudba prehranskih dopolnil z živimi bakterijami močno povečala. Marca 2019 smo na slovenskem trgu našli devet takih, ki so namenjeni dojenčkom. Pregledali smo po tri različne serije istega izdelka. Z mikrobiološkimi analizami smo preverili skladnost deklaracij z dejansko prisotnimi vrstami bakterij v izdelkih in njihovim številom. Dodatni namen naloge je bil primerjati rezultate analiz, narejenih po navodilu proizvajalca, s splošnimi protokoli. Število bakterij smo ugotavljali s klasično metodo štetja kolonij na selektivnih gojiščih ali s pretočno citometrijo, če je proizvajalec navedel to metodo. Na deklaracijah smo zasledili nekaj nepravilnosti v poimenovanju bakterij in uporabo besede »probiotik«, ki v EU ni dovoljena za prehranska dopolnila. Pri vseh izdelkih je bilo navedeno le skupno število mikroorganizmov, tudi če je bilo sevov več (3 od skupno 9 izdelkov). Popolnoma ustrezno deklaracijo je imel le en izdelek. V osmih izdelkih je bilo število KE ali živih bakterij ustrezno, v eni šarži enega izdelka pa je bilo število živih bakterij, ugotovljeno s pretočno citometrijo, premajhno. Z metodama MALDI-TOF MS in PCR smo preverjali prisotnost navedenih bakterijskih vrst. Metoda MALDI-TOF MS se je izkazala za enostavno in hitro, vendar v nekaterih izdelkih nismo uspeli zanesljivo dokazati prisotnosti bakterij vrst Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus ali Bifidobacterium bifidum. To težavo bi bilo mogoče odpraviti s pregledom večjega števila kolonij. Tri izdelke smo analizirali tudi po navodilu proizvajalca, vendar večjih razlik v rezultatih, v primerjavi s splošnimi protokoli, ni bilo.

Ključne besede

prehranska dopolnila;probiotik;Lactobacillus;Bifidobacterium;Streptococcus thermophilus;masna spektrometrija z MALDI-TOF;pretočna citometrija;PCR;identifikacija bakterij;

Podatki

Jezik: Slovenski jezik
Leto izida:
Tipologija: 2.09 - Magistrsko delo
Organizacija: UL BF - Biotehniška fakulteta
Založnik: [R. Černe]
UDK: 579.67:613.292-053.2:543.51
COBISS: 33015043 Povezava se bo odprla v novem oknu
Št. ogledov: 453
Št. prenosov: 108
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Sekundarni jezik: Angleški jezik
Sekundarni naslov: Quality of dietary supplements for infants containing viable bacteria on Slovenian market
Sekundarni povzetek: In recent years, the supply of dietary supplements with live bacteria has increased significantly. In March 2019, we found nine of these products on the Slovenian market, intended for babies. We examined three different batches of the same product. We used microbiological analyses to check the compliance of the declaration with the actual types of bacteria present in the products and their number. Additional purpose of this study was to compare the results of analyses performed according to the manufacturer's instructions with general protocols. The number of bacteria was determined by the classical method of colony counting on selective media and by flow cytometry, when the producer stated this method. On the declarations, we found some irregularities in the naming of bacteria and the use of the word "probiotic" which is not allowed for dietary supplements in EU. For all products, only the total number of microorganisms was reported, even if there were more strains (3 out of 9 total products). Only one product had a fully appropriate label. In eight products, the number of cfu or viable bacteria was adequate, while in one batch of one product the number of bacteria, determined by flow cytometry, was too low. The presence of labeled bacterial species was checked by MALDI-TOF MS and PCR methods. The MALDI-TOF MS method has proven to be easy and fast, but in some products, we have not succeeded to prove the presence of Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus or Bifidobacterium bifidum. This problem could be solved by examining a larger number of colonies. Three products were also analysed according to the manufacturer's instructions, but there were no differences compared to the general protocols.
Sekundarne ključne besede: dietary supplements;probiotic;Lactobacillus;Bifidobacterium;Streptococcus thermophilus;MALDI-TOF mass spectrometry;flow cytometry;PCR;bacteria identification;
Vrsta dela (COBISS): Magistrsko delo/naloga
Študijski program: 0
Konec prepovedi (OpenAIRE): 1970-01-01
Komentar na gradivo: Univ. v Ljubljani, Biotehniška fak., Oddelek za živilstvo
Strani: XI, 46 f., [11] f. pril.
ID: 12023858