Fig. 1: Taxonomic analyses of biofilms from human aging cohort.

Fecal microbiota cultured in vitro on a polymicrobial anaerobic biofilm model underwent 16S rRNA V3-V4 gene sequencing. The study groups include individuals aged 30–70 years (n = 13), individuals aged 70 years and above characterized as healthy aging (robust, n = 15) and +70 years prefrail (n = 14). A The stacked bar plots illustrate the relative abundance of the five major Phyla and their top five most abundant Families. Each individual is depicted as a separate bar plot, highlighting taxonomic variations. B For each individual, the average of the lowest values from four different beta-diversity matrices (Bray–Curtis, Jaccard, unifrac, and weighted unifrac) represented individual uniqueness. Statistical significance was determined by ANOVA followed by Tukey’s for multiple comparisons, where P < 0.05 was considered significant (* for P < 0.05, *** for P < 0.0010). C Heatmap represents Kendall’s correlation coefficients between biofilm taxa counts and clinical parameters from human donors. Clinical parameters include discrete and continuous clinical features: household (1: solo 2: with a partner), gender (1: male, 2: female), MNA score, Charlson index, age, and Fried Frailty Index. The color gradient from blue to red signifies negative to positive correlations, and * corresponds to Kendall’s P value < 0.05. For enhanced clarity, the heatmap was filtered to include only significantly positive or negative correlations (P < 0.05).