Soil microbial improvement using enriched vinasse as a new abundant waste

Abstract

This study proposes the use of vinasse, an inexpensive and readily available waste biopolymer, as a fundamental component of a waste culture medium that can enhance the effectiveness and cost-efficiency of the Microbial-Induced Calcite Precipitation (MICP) method for sustainable soil improvement. Vinasse enriched with urea, sodium caseinate, or whey protein concentrate is employed to optimize bacterial growth and urease activity using Taguchi Design of Experiments (TDOE) and statistical analysis. The results show that using the new culture medium yields a 91 times reduction in the cost of culture medium compared to conventional Nutrient Broth (NB) culture medium while improving soil shear strength parameters. Furthermore, the recycling of vinasse as a waste product can promote the progress of a circular economy and reduce environmental pollution. This study provides a promising approach to achieving cost-effective and sustainable soil improvement using waste biopolymers.