Synergistic effects of beneficial bacteria on growth performance and nutritional quality of white button mushroom ( <i>Agaricus bisporus</i> )

The white button mushroom (Agaricus bisporus) is one of the most widely cultivated and consumed edible mushrooms worldwide, valued for its nutritional and health-promoting properties. Although recent studies suggest that bacteria can enhance mushroom growth and yield, the specific role of beneficial bacteria in improving productivity and bioactive compound content remains insufficiently understood. This study investigated the effects of individual and combined bacterial inoculations on A. bisporus yield, nutritional composition, and functional metabolites. Six treatments were tested in a completely randomized design, including a control (no inoculation), Bacillus subtilis ICMP 368, Pseudomonas fluorescens ICMP 3512, Pseudomonas putida ICMP 19449, Azotobacter chroococcum ICMP 15214, and co-inoculation of all four strains applied to the casing soil. Co-inoculation increased yield to 34.64 kg per 100 kg compost and biological efficiency to 125.96%, representing an 18.9% improvement over the control. Co-inoculated mushrooms exhibited higher ergosterol (3.92 mg/g dry weight), protein (3.16 g/100 g fresh weight), and trehalose (2.53 g/100 g fresh weight) contents, while the highest β-glucan level (9.86 g/100 g dry weight) was obtained with P. putida inoculation. Overall, co-inoculation of beneficial bacteria effectively enhanced both yield and nutritional quality of A. bisporus, whereas individual strains selectively improved specific bioactive compounds.