A thorough study was done to test the reactivity of the Folin-Ciocalteu (F-C) reagent towards various compound classes. Over 80 compounds were tested. Compound classes included phenols, thiols, vitamins, amino acids, proteins, nucleotide bases, unsaturated fatty acids, carbohydrates, organic acids, inorganic ions, metal complexes, aldehydes and ketones. All phenols, proteins and thiols tested were reactive towards the reagent. Many vitamin derivatives were also reactive, as were the inorganic ions Fe+2, Mn+2, I− and SO3−2. Other compounds showing reactivity included the nucleotide base guanine and the trioses glyceraldehyde and dihydroxyacetone. Copper complexation enhanced the reactivity of salicylate derivatives towards the reagent while zinc complexation did not. Several amino acids and sugars which were reported to be reactive towards the F-C reagent in earlier studies were found not to be reactive in our study, at least in the concentrations used.
Reaction kinetics of each compound with the F-C reagent were also measured. Most compounds tested showed a biphasic kinetic pattern with half lives under one minute. Trolox and ascorbic acid displayed a rapid monophasic pattern in which the reaction reached endpoint within one minute.
In summary, our study has shown that the F-C reagent is significantly reactive towards other compounds besides phenols. As other investigators have suggested, the F-C assay should be seen as a measure of total antioxidant capacity rather than phenolic content. Since phenolics are the most abundant antioxidants in most plants, it gives a rough approximation of total phenolic content in most cases.
Co-Administration of Cu(II) chelates are reported to decrease life threatening Cisplatin [Pt(II) (NH3)2(CL)2]-induced acute degenerative renal, gastrointestinal, thymic, and bone marrow states consistent with serious necrotizing and immune-mediated inflammatory disease. Initially it was found that copper sulfate treatment completely prevented lethality as well as gastric and nephrotoxicity without compromising Pt(II) (NH3)2(CL) 2 antineoplastic activity, which led to suggestions that prior Cu(II)-treatment be used clinically to prevent serious side effects of Pt(II) (NH3)2(CL)2-treatment. In the course of these studies it was discovered that Cu(II)-treatments alone inhibited neoplastic growth and increased survival of rat and mouse models of cancer. Subsequently it was discovered that a stable non-toxic and non-polar lipophilic chelate, Copper(II)2(3,5-diisopropylsalicylate)4, caused redifferentiation of cultured neuroblastoma and mouse muscle-implanted mammary adenocarcinoma without neoplastic cell killing. Another stable non-toxic and non-polar lipophilic chelate, Copper(II)2(3,5-ditertiarybutylsalicylate)4, was found to prevent Bax-initiated and caspases-3-activation mediated apoptosis. These remarkable observations are concluded to be due to enzyme-mimetic or modulating reactivities of Cu(II) chelates and/or facilitation of Cu(II or I)-dependent enzyme syntheses required to overcome inflammatory-neoplastic disease states. Further, approaches to treating neoplastic diseases by removal of Cu from tissues with ammonium tetrathiomolybdate in an anticopper approach to therapy are not well founded based upon existing scientific literature.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.