Morphological, physiological, and biochemical properties of fungal cells located on a liquid-surface and an organic–aqueous interface

In general, morphological, physiological, and biochemical properties of fungal cells are drastically different among solid-state (SSC), liquid-surface (LSC), and submerged cultivation (SmC) systems. In addition to these traditional cultivation systems, a unique liquid-surface cultivation [liquid-surface immobilization (LSI)] system and interface cultivation systems [extractive liquid-surface immobilization (Ext-LSI) system; liquid–liquid interface bioreactor (L–L IBR)] bring some interesting fungal morphological, physiological, and biochemical characteristics. The unique properties of fungal cells located on a liquid-surface and an organic–aqueous interface are very important to application of fungi to the production of enzymes, metabolites, and bioconversion products. In this review, the unique and important characteristics of fungal cells immobilized in the LSI, L–L IBR, and Ext-LSI systems are explained in detail. Moreover, some application of the cultivation systems to fermentation, enzyme production, and microbial transformation are introduced.