Naslov
Characterisation of cultivable community of Non-Starter Lactic Acid Bacteria from traditional Istrian ewe's cheese

Autori
Skelin, Andrea ; Mrkonjić Fuka, Mirna ; Redžepović, Sulejman ; Čanžek Majhenič, Andreja

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

Izvornik
5th Croatian Congress of Microbiology with International Paticipation / Černi, S., Šeruga Musić, M., Škorić, D. - Zagreb : Hrvatsko mikrobiološko društvo, 2012, 47-47

ISBN
978-953-778-05-7

Skup
5th Croatian Congress of Microbiology with International Paticipation

Mjesto i datum
Primošten, Hrvatska, 26.09.2012. - 30.09.2012

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
NSLAB; phenotyping; genotyping

Sažetak
The microbial flora of traditional cheese, particularly those made from raw milk is very complex. Predominant inhabitants of such microbiota of raw milk cheese are nonstarter lactic acid bacteria (NSLAB) composed of many strains important for cheese ripening and flavour development. Heterogeneity of NSLAB strains with unique and diverse properties represents a key factor for improving authenticity of traditional cheese. Lactobacilli constitute a significant proportion of NSLAB communities. The objective of current study is to describe the diversity of indigenous cultivable community of the lactobacilli associated with the production of traditional Istrian cheese and to get a collection of well characterized strains. The samples of raw milk and cheese were collected from three different farms in Istria during ripening. A total of 212 mesophilic and thermophilic lactobacilli isolates as well as bulk colonies were investigated using culture- dependent approach combining phenotyping and genotyping. Biochemical fingerprinting with PhenePlate-LB system preliminary grouped 212 isolates in 16 distinct PhP types. Only one representative isolate from each PhP cluster was further analyzed by genotyping for a reliable identification at the genus and species level by employing PCR techniques and sequencing of 16S rRNA genes. Sequence analysis of 16S rRNA revealed the presence of Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus casei, Lactobacillus paracasei and Lactobacillus rhamnosus. Lactobacilli were screened for possible resistance against seven selected antibiotics: ampicillin, tetracycline, penicillin, rifampin, clindamycin, erythromycin and vancomycin. Although there was no clear pattern for antimicrobial susceptibility to most tested antibiotics, all representative isolates were resistant to vancomycin. The analysis of bulk colonies by denaturing gradient gel electrophoresis (DGGE) identified Lactobacillus plantarum and Lactobacillus brevis as predominant members of lactobacilli population. Pediococcus pentosaceus, Pediococcus acidilactici, Streptococcus sp. and Leuconostoc mesenteroides were also detected as part of the analysed consortia. Such complex viable community can be considered as a fundamental factor for the maintenance of typical features of the investigated cheese and will be preserved and used in further strain selection process.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Poljoprivreda (agronomija)

POVEZANOST RADA