Edible electrospun zein nanofibrous scaffolds close the gaps in biofilm formation ability between microorganisms

Abstract

Biofilm is an important survival mode of microorganisms in nature. Biofilm culture is supposed to be a way of learning from nature to endow microorganisms with a strong tolerance. However, microorganisms possess different biofilm formation abilities, and universal scaffolds, especially edible scaffolds, suitable for fast biofilm formation are not found yet. Zein is a hydrophobic and biocompatible prolamine-rich protein from corn and is one of the most used biomacromolecules now. In this work, natural zein was utilized to produce electrospun zein nanofibrous biomaterial. The results demonstrate that edible electrospun zein nanofibrous scaffolds significantly enhance biofilm formation, where bacterial probiotics and yeasts are 0.9–1.4 Log cfu/cm2 (8–25 × ) and 1.7–3.3 Log cfu/cm2 (50–2000 × ) higher than the values on polystyrene plates and zein films, respectively. Gaps in biofilm formation abilities between bacteria and yeasts are narrowed from 1.7–1.8 Log cfu/cm2 (50–63 × ) to 0.5–0.6 Log cfu/cm2 (3–4 × ), respectively. Biofilms quickly formed on electrospun zein nanofibrous scaffolds before the occurrence of serious swelling deformation of the scaffolds. This is the first attempt to use edible electrospun fibrous scaffolds based on natural biomacromolecules for enhancing biofilm formation, crucially important for the application of probiotics and yeast in food and medical industries. Electrospun zein nanofibrous scaffolds can serve as powerful tools to enhance the biofilm formation of valuable food microorganisms and close the huge gaps in biofilm formation abilities between microorganisms, providing a convenient and universal strategy to produce biofilm-phenotyped probiotics and yeasts.