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In this work, we review some physical methods of macroscopic experiments, which have been recently argued to be promising for the acquisition of valuable characteristics of biomolecular structures and interactions. The methods we focused on are electron paramagnetic resonance spectroscopy, Raman spectroscopy, and differential scanning calorimetry. They were chosen since it can be shown that they are able to provide a mutually complementary picture of the composition of cellular envelopes (with special attention paid to mycobacteria), transitions between their molecular patterning, and the response to biologically active substances (reactive oxygen species and their antagonists-antioxidants-as considered in our case study).

Recent interest in the antioxidant capacity of foods and beverages is based on the established medical knowledge that antioxidants play an essential role in counteracting the damaging effects of free radicals, preventing human neurodegenerative diseases, cardiovascular disorders, and even cancer. At the same time, there is no "the method" that uniquely defines the antioxidant capacity of substances; moreover, the question of interrelation between results obtained by different experimental techniques is still open. In this work, we consider the trolox equivalent antioxidant capacity (TEAC) values obtained by electron paramagnetic resonance (EPR) spectroscopy and ultraviolet-visible (UV-vis) spectroscopy using the classic objects for such studies as an example: red, rosé, and white wine samples. Based on entirely different physical principles, these two methods give values that are not so simply interrelated; this creates a demand for machine learning as a suitable tool for revealing quantitative correspondence between them. The consideration consists of an approximate correlation-based analytical model for the key argument (i.e., TEACEPR) with subsequent adjustment by machine learning-based processing utilizing the CatBoost algorithm with the usage of auxiliary chemical data, such as the total phenolic content and color index, which cannot be accurately described by analytical expressions.

Presented here is a comprehensive study on the antioxidant properties of various alcoholic beverages: beers, wines, tinctures, and strong spirits, including whisky, brandy, cognac, vodkas, and liquors. The Trolox equivalent antioxidant capacity (TEAC) of each of these various alcoholic beverages is determined using an electron paramagnetic resonance (EPR) method, which is based on a semiempirical correlation. Moreover, the EC 50 parameter was determined on the basis of the dependences of the TEAC values obtained by this mathematical equation. Moreover, the total phenolic content (TP) and color index, which have a direct influence on the antioxidant properties of the alcoholic beverages, were identified. The results showed that all the investigated alcoholic beverages (ABs), with the exception for vodkas, exhibit antioxidant properties. By performing a statistical analysis, it was found that the TEAC value significantly depends on the TP, production method, and raw material from which the alcohol was made. However, it is assumed that the TEAC value of alcoholic beverages is independent of the alcohol content.