Cheese and milk are stapled dairy products consumed globally. However, adulterants in these products pose significant health risks and compromise their quality. Analytical techniques are crucial in detecting and quantifying adulterants to combat adulteration. This opinion explores the problem of cheese and milk adulteration, highlights the role of spectroscopic techniques (fluorescence spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and infrared (IR) spectroscopy) in adulteration detection, and compares their effectiveness with the well-established high-performance liquid chromatography (HPLC) method. The advantages and limitations of each technique are discussed, providing valuable insights into their applications to ensure the authenticity and safety of cheese and milk products.

Lactate dehydrogenase (LDH) is an enzyme that catalyzes the reversible conversion of lactate to pyruvate while reducing NAD⁺ to NADH (or oxidizing NADH to NAD⁺). Due to its central role in the Warburg effect, LDH-A isoform has been considered a promising target for treating several types of cancer. However, research on inhibitors targeting LDH-B isoform is still limited, despite the enzyme’s implication in the development of specific cancer types such as breast and lung cancer. This study aimed to identify small-molecule compounds that specifically inhibit LDH-B. Our in silico analysis identified eight commercially available compounds that may affect LDH-B activity. The best five candidates, namely tucatinib, capmatinib, moxidectin, rifampicin, and acetyldigoxin, were evaluated further in vitro. Our results revealed that two compounds, viz., tucatinib and capmatinib, currently used for treating breast and lung cancer, respectively, could also act as inhibitors of LDH-B. Both compounds inhibited LDH-B activity through an uncompetitive mechanism, as observed in in vitro experiments. Molecular dynamics studies further support these findings. Together, our results suggest that two known drugs currently being used to treat specific cancer types may have a dual effect and target more than one enzyme that facilitates the development of these types of cancers. Furthermore, the results of this study could be used as a new starting point for identifying more potent and specific LDH-B inhibitors.

Reaction of an aqueous solution of NaVO₃ or a methanol solution of [VO(acac)₂] with 2,5-bis((bis(2-hydroxyethyl)amino)methyl)hydroquinone, H₆bdeah, results in the formation of two major vanadium species characterized by X-ray crystallography: the [(V⁵⁺O)₂(bdeah)] and the [(V^4.5+O)₂(bdeas)S₂] (S = DMSO or MeOH). The vanadium ions in the two species have a trigonal pyramidal and an octahedral coordination sphere respectively. Variable temperature UV-Vis and ⁵¹V NMR spectroscopy as well as EPR and electrochemistry showed a temperature induced electron transfer. The diamagnetic [(V⁵⁺O)₂(bdeah)] is the main species at high temperature. At low temperature one electron is transferred from the bdeah⁶⁻ to the two vanadium centers resulting in the [(V^4.5+O)₂(bdeas)S₂] species [H₅bdeas = 2,5-bis((bis(2-hydroxyethyl)amino)methyl)-1,4-semiquinone]. The thermodynamic parameters of this intramolecular electron transfer were calculated by UV-Vis (ΔH = −36 ± 2 kJ mol⁻¹ and ΔS = −129 ± 5 J mol⁻¹ K⁻¹) and ⁵¹V NMR spectroscopy (ΔH = −37 ± 2 kJ mol⁻¹ and ΔS = −109 ± 5 J mol⁻¹ K⁻¹). The electron transfer is a result of the large change of entropy which is associated with the ligation of the solvent molecules and the geometry change. EPR spectroscopy shows that most of the electron density in [(V^4.5+O)₂(bdeas)S₂] is mainly located on the two vanadium ions.