Kalanetra, K. | bioRxiv Science

bioRxiv2025

Indoor environmental conditions shape the microbial landscape of food production facilities across space and time

The microbial communities inhabiting food production environments are distinguished from those of other built environments in their capacity to influence food quality and safety, impacting consumer health. However, how indoor environmental conditions drive the bacterial and fungal communities of food production facilities remains largely unknown. In this study of five commercial food production facilities, we employed remote wireless sensors paired with marker-gene amplicon sequencing (bacterial 16S rRNA genes and fungal ITS) of processing equipment and non-processing built environment surfaces (N=2,329) to profile spatial and longitudinal changes in bacterial and fungal communities, and their association with indoor climate. We identify multiple associations between indoor environmental conditions and microbial community structure, demonstrating the role of the indoor environment in shaping microbial communities on food processing and non-processing surfaces. This suggests that indoor climate could be manipulated to rationally modify surface communities, with the aim of enhancing food quality and safety.

microbiology↗

bioRxiv2025

A Milk Fat Globule Membrane-enriched dairy co-product modulates gut Faecalibaculum rodentium metabolism in association with the prevention of cognitive impairment in aging male Wistar rats

Consumption of the milk fat globule membrane (MFGM) by infants is linked to enhanced neurodevelopment and sustained cognitive improvements later in life. Aging, by contrast, is often marked by neurodegeneration and cognitive decline-a growing concern in the U.S. as 6.9 million Americans live with Alzheimers disease (AD). As such, identifying interventions to prevent cognitive impairment are imperative. The whey protein phospholipid concentrate (WPPC), a dairy co-product, is enriched in MFGM glycoconjugates. Given the cognitive health benefits conferred by MFGM consumption in early life, we previously found that high-fat (HF) diet induced cognitive impairment in aging male Wistar rats was prevented by supplementating with a 1.6% or 10% WPPC in the diet, compared to control rats fed a low-fat (LF) diet. We hypothesized that WPPC exerts protective effects against cognitive impairment through the gut-brain axis by modulating gut microbial composition and metabolism. To test this, we analyzed 16S rRNA sequencing data from fecal samples of aged male Wistar rat (4 months old) fed a LF, HF, HF + 1.6% WPPC, or HF + 10% WPPC diet (n=9-10/group). Compared to LF, the HF diet reduced the abundance of the Erysipelotrichaceae family, particularly the species Faecalibaculum rodentium, which increased numerically with the 10% WPPC diet. Interestingly, Erysipelotrichaceae relative abundance correlated with hippocampal memory storage (spearman correlation=0.4, p=0.034). In vitro growth assays confirmed that F. rodentium grew robustly in isolation on WPPC glycoconjugates and on constituent WPPC components (p<0.05). RNA sequencing of F. rodentium grown on the WPPC MFGM glycoconjugates versus glucose (n=3/group) revealed significant upregulation of genes involved in in amino acid metabolism and fatty acid oxidation (FDR<0.05). Collectively this data suggests a potential role for F. rodentium in preventing cognitive impairment through the gut-brain axis by metabolizing the WPPC that may act on the host.

microbiology↗