# Determination of the Antimicrobial Effects of Synbiotic Kefir Produced from Buffalo Milk Enriched with Galactooligosaccharides and Inulin

## TL;DR

This study examines how different factors affect the antimicrobial properties of synbiotic kefir made from buffalo milk.

## Contribution

The study identifies how fat content, prebiotics, production methods, and storage time influence kefir's antimicrobial activity.

## Key findings

- Fat content significantly affects antimicrobial activity against E. faecalis, L. monocytogenes, and E. coli.
- Commercial culture and prebiotics enhance antimicrobial activity in kefir.
- Storage time increases antimicrobial activity against all tested pathogens.

## Abstract

In this study, the effects of fat content (0.5 and 3.5%),
prebiotics
(galactooligosaccharides [GOS] and inulin), production method (traditional
and commercial), and storage period (21 days at 3 ± 1 °C)
on the antimicrobial activity of synbiotic kefirs produced using buffalo
milk against certain pathogenic microorganisms (Staphylococcus
aureus, Bacillus subtilis, Enterococcus faecalis, Listeria monocytogenes, Pseudomonas
aeruginosa, Escherichia coli, and Candida albicans) were determined.
Variations in fat content significantly affected antimicrobial activity
against E. faecalis (p < 0.01), L. monocytogenes (p < 0.01), and E. coli (p < 0.01); the production method influenced S. aureus (p < 0.01), B. subtilis (p < 0.05), E. faecalis (p < 0.01), E. coli (p < 0.01), and C. albicans (p < 0.01), while
prebiotic addition affected S. aureus (p < 0.01), L. monocytogenes (p < 0.05), E. coli (p < 0.05), and C. albicans (p < 0.01). The storage period had a significant
effect (p < 0.01) on all examined pathogens, and
antimicrobial activity increased as storage time progressed. In general,
the use of commercial culture and prebiotics in kefir production enhanced
antimicrobial activity. The effects of inulin (on S.
aureus, C. albicans) and GOS (on L. monocytogenes, E. coli, C. albicans) varied across microorganisms. Based on the average zone diameters
produced by the kefir samples: The highest activity against S. aureus was observed in inulin-containing and cultured
samples, against B. subtilis, it was
observed on the seventh day in cultured samples, against C. albicans, in inulin-containing and cultured samples
(on day 21), against L. monocytogenes, in GOS-enriched and 0.5% fat samples, as well as in inulin-added
samples (on day 21), against E. faecalis, in 0.5% fat and cultured samples (on day 21), against E. coli, in 3.5% fat, GOS-added, and cultured samples,
and against P. aeruginosa, activity
was detected on the seventh and 14th days of storage.