Investigation of the in vitro antioxidant activity of fermented tomato pruning residues and its effects on biochemical and hematological parameters of rats

Abstract

In the tomato greenhouse production process, a by-product emerges in the form of greenhouse residues. One of these residues is leaf pruning residue, which poses an environmental pollution problem in terms of waste management. The purpose of this work was to investigate the use of fermented tomato leaves (FTL) as an animal feed additive and its potential to mitigate the environmental pollution problem caused by greenhouse pruning residues. The pruning residues were fermented and their in vitro antioxidant activity (AOA) levels were analyzed using 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), reducing power (RP), and total phenolic content (TPC) assays. Wistar albino rats were fed diets containing standard rat chow with 25% FTL pellet. Performance parameters (feed intake, water intake, and body weight gain) of the rats were recorded for 21 days. Plasma biochemistry, hematological profile, and blood redox parameters (total oxidant status, TOS; total antioxidant status, TAS) were measured in rats euthanized after 21 days of treatment. It was determined that FTL had high AOA, which was due to nonphenolic components in FTL. There was no adverse effect of the test diet on the biochemical and hematological profile, and redox parameters, while an increase was observed in the feed intake. This study shows that FTL has nonphenolic AOA in vitro and that the diet prepared with 25% FTL has no detrimental effect on the measured parameters and can be used as an animal feed additive.