Meki Boutaiba Benklaouz

Algeria

Microbial Diversity of Raw Milk and Artisanal Dairy Products from Multiple Animal Species and Antibacterial Activity of native Lactic Acid Bacteria

Boutaiba Benklaouz Meki1*, Benameur Qada2, Smaranda Crăciun3, George Cosmin Nadăș4, Adriana Györke5
1Department of Agronomy, Institute of Natural and Life Sciences, University Center Nour El Bachir- El Bayadh, El Bayadh 32000, Algeria;
2Department of Agronomy, Faculty of Nature and Life Sciences, University Abdelhamid Ibn Badis of Mostaganem, 27000 Mostaganem, Algeria;
3Department of Microbiology, Immunology and Epidemiology, Faculty of Veterinary 4Medicine, University of Agricultural Sciences and Veterinary Medicine, 400372 Cluj-Napoca, Romania.
5Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, 400372 Cluj-Napoca, Romania.

Abstract

Background

BACKGROUND: The microbial composition of raw milk and artisanal dairy products is influenced by animal species, geographical origin, and product type, with significant implications for food safety and functional characteristics. This study aimed to characterize the microbial diversity of raw milk and artisanal dairy products from different animal species in Algeria and to evaluate the antibacterial activity of lactic acid bacteria (LAB).

Methods

METHODS: Five dairy product samples were analyzed in this study, including cow raw milk and buttermilk from camels, cows, sheep, and goats. Microbial identification was performed using MALDI-TOF mass spectrometry. The antibacterial activity of LAB isolates was assessed in vitro via a disk diffusion assay against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923.

Results

RESULTS: Sixteen microbial strains were recovered in this study, reflecting the microbial diversity of the analyzed samples. The isolates comprised six LAB: Lactobacillus plantarum (n=1), Limosilactobacillus fermentum (n=1), Lacticaseibacillus paracasei (n=1), Weissella confusa (n=1), Enterococcus faecalis (n=1), and Streptococcus parasanguinus (n=1). Non-LAB bacterial isolates included Escherichia coli (n=2) and Cytobacillus firmus (n=1), while yeast species consisted of Kluyveromyces marxianus (n=3), Candida tropicalis (n=3), and Pichia kudriavzevii (n=1). Notably, cow’s buttermilk exhibited the greatest microbial diversity compared to products from other animal species. All LAB isolates exhibited antibacterial activity against the tested ATCC strains, with inhibition zone diameters ranging from 7.00 to 14.50 mm.

Conclusions

CONCLUSIONS: This study highlights the diversity and richness of the indigenous dairy microbiota and demonstrates that certain LAB strains possess substantial antibacterial activity, suggesting their potential application in the development of functional fermented dairy products. These findings provide a basis for the exploitation of local microbial resources for food safety and biotechnological applications.