Proton Exchange in Water/Mycelium System: Transdisciplinary Out-of-Equilibrium Thermodynamic Approach Using Potentiometric Titration

Abstract

In this study, we used potentiometric titration to investigate the interaction of the saprophytic fungus Trametes villosa in an aqueous environment. The study of this biological complex system allowed us to observe the evolution of out-ofequilibrium hydrogen ion potential states after systematic perturbations. The responses of the complex system to perturbations were interpreted from relations that provided qualitative response patterns for mycelium in agreement with their basic structural and organizational characteristics. We consider this to be a transdisciplinary example of the behavior of general systems with thermodynamic properties of great ecological relevance, being specifically related to the negentropic properties of heterogeneous systems.

Humic acid potentiometric response patterns: out-of-equilibrium properties and species distribution modeling

“…These characteristics are strongly related to soil stability/fertility and the health of ecosystems under different conditions, such as in the highly energetic, biodiverse natural/forest soils, and also soils of alternative sustainable agricultural systems. We propose that our simple methodology is appropriate for use in studies on a wide variety of complex systems, including other humic substances, soils, root systems and, importantly, integer samples or raw complex systems [12]. Lastly, it is important to note that in the study of complex systems the use of potentiometry (considering out-of-equilibrium thermodynamics) is proposed to contribute with transdisciplinar (e.g., agroecology) investigation and the development of socially-scientifically-technologically relevant research focused on intermediate and accessible technologies [1,12,[23][24][25].…”

“…where y(x) is the measured pH, x is time t, a is the quasi-stable pH value when x tends to infinity, b is the variation of y(x) (ΔpH) from x = 0 to x = ∞ and c is the exponential coefficient which, multiplied by b, defines the shape of the pH versus time variation curve and is related to the out-of-equilibrium negentropic stability of the studied sample [12].…”

“…Also, in the investigation of natural complex systems (integer or raw complex systems) using potentiometric methods, out-of-equilibrium thermodynamic states can be observed in terms of seconds, minutes, or hours [12]. It is interesting to note that this is not a property of all chemical systems (for example, small molecules or homogeneous solutions of pure substances), but out-ofequilibrium stable thermodynamic states are characteristic of complex, highly organized heterogeneous (negentropic) systems, such as humic substances, soils, microbiological systems, networks, root systems, and many others found in natural environments [8][9][10][11][12][13][14][15][16].…”

“…It is interesting to note that this is not a property of all chemical systems (for example, small molecules or homogeneous solutions of pure substances), but out-ofequilibrium stable thermodynamic states are characteristic of complex, highly organized heterogeneous (negentropic) systems, such as humic substances, soils, microbiological systems, networks, root systems, and many others found in natural environments [8][9][10][11][12][13][14][15][16]. A simple and important relation (for our approach and other related strategies) has been identified in modern out-of-equilibrium thermodynamics [15], which involves free energy and entropy:…”