Piranhea trifoliata extracts ameliorate muscular decline in Drosophila melanogaster exposed to Paraquat.

In this study, we have demonstrated, for the first time, the muscular protective effects of Piranhea trifoliata bark extract against Paraquat (PQ)-induced oxidative stress in Drosophila melanogaster. Exposure of D. melanogaster (Canton Special) to PQ caused oxidative stress, as evidenced by protein carbonyl and elevated acetylcholinesterase (AChE) activity levels. However, a diet supplemented with the P. trifoliata extracts (0.1 mg/ml) for 10 days ameliorates protein carbonyl levels and enzymatic activities of AChE and citrate synthase to prevent PQ damage. Also, P. trifoliata bark extracts showed in phytochemical assays the presence of phenols, at 46.06 mg EAG/g extract of total phenolic compounds, and a 40% 2,2-diphenyl-1-picryl-hydrazyl scavenging effect. The study showed the muscular protective function of the P. trifoliata extracts in D. melanogaster exposed to PQ. On the basis of the results, we contemplate that the bark of P. trifoliata might prevent and ameliorate human diseases caused by oxidative stress. The muscular action of the P. trifoliata extract can be attributed to the antioxidant constituents, while the precise mechanism of its action needs further investigation.

Natural Antioxidant Evaluation: A Review of Detection Methods.

Antioxidants have drawn the attention of the scientific community due to being related to the prevention of various degenerative diseases. The antioxidant capacity has been extensively studied in vitro, and different methods have been used to assess its activity. However, the main issues related to studying natural antioxidants are evaluating whether these antioxidants demonstrate a key role in the biological system and assessing their bioavailability in the organism. The majority of outcomes in the literature are controversial due to a lack of method standardization and their proper application. Therefore, this study aims to compile the main issues concerning the natural antioxidant field of study, comparing the most common in vitro methods to evaluate the antioxidant activity of natural compounds, demonstrating the antioxidant activity in biological systems and the role of the main antioxidant enzymes of redox cellular signaling and explaining how the bioavailability of bioactive compounds is evaluated in animal models and human clinical trials.

Simple colorimetric method to determine the in vitro antioxidant activity of different monoterpenes.

The development of simple, fast and reproducible techniques that provide information about the antioxidant activity (AA) of different compounds is essential to screen and discover new molecules with potential applications in the therapeutic, cosmetic, toxicological and food fields. Here, a novel and simple colorimetric method ("BCB assay") is proposed for measuring the AA of chemical compounds by protection of the reporter dye Brilliant Cresyl Blue (BCB) from loss of color due to oxidation by hypochlorite (a physiological oxidant). The decay in BCB blue color (λmax = 634 nm) in the presence of hypochlorite occurred in only 5 min and was used to track the AA of different molecules. Particularly, the AA of monoterpenes was demonstrated and used to quantify them at milimolar concentrations. Natural antioxidants like vitamins C and E, resveratrol, dithiothreitol, N-actyl-l-cysteine and glutathione were used as controls to validate the assay. Linalool, geraniol and 1,8-cineole were tested and showed in vitro AA in a concentration-dependent manner. The monoterpene concentrations providing 50% protection against oxidation (AA50) were 2.3, 36.2 and 135.0 mM for linalool, geraniol and 1,8-cineole respectively, suggesting interesting AA. The method provides a useful, fast, simple and low-cost tool to determine the in vitro AA of different molecules.