Preliminary Evaluation of the Gut Microbiota Modulatory Potential of Malaysian Kefir Water in Ageing Mice

Ageing is often accompanied by gut microbiota alterations that contribute to dysbiosis-a recognised hallmark of ageing and a risk factor for neurodegenerative diseases. Probiotic interventions offer a promising approach to restore microbial homeostasis. This preliminary study explored the potential modulatory effects of Malaysian kefir water, a <i>Lactobacillus</i>-enriched fermented beverage with previously reported antioxidant and neuroprotective properties in D-galactose-induced ageing mice. Kefir water was administered as both a pre-treatment and co-treatment, and gut microbiota changes were assessed using 16S rRNA metagenomic sequencing of faecal samples. Alpha and beta diversity analyses showed a stable microbial diversity across treatments. However, preliminary descriptive trends suggested that kefir water may influence specific bacterial populations. Increases were observed in <i>Muribaculaceae</i> and <i>Lactobacillaceae</i>, along with apparent decreases in <i>Lachnospiraceae</i> and <i>Prevotellaceae</i>. Both kefir treatments tended to increase the abundance of <i>Ligilactobacillus</i>, with the co-treatment group appearing to restore the <i>Firmicutes</i>/<i>Bacteroidota</i> ratio toward control levels, while the pre-treatment group showed a tendency to further reduce this ratio. Collectively, these findings provide preliminary indications that kefir water may hold potential as a dietary approach to modulate gut microbial changes associated with ageing. However, confirmation through studies with larger sample sizes and broader analytical coverage is necessary to substantiate these initial observations.