Abstract
The aim of this study was to evaluate the most effective extraction condition (temperature, solvent type and time) for recovery of high-value phytochemicals present in the Tabernaemontana catharinensis leaves (TC) and to assess their effect on biochemical parameters in streptozotocin-induced diabetic rats. The extraction of phenolic compounds from TC using a factorial design (FD) 2³, high performance liquid chromatography (HPLC), response surface methodology (RSM) and principal component analysis (PCA) were studied. It was found that the optimal conditions for extraction of phenolics were higher temperature (65 °C) and time (60 min) using ethanol as extractor solvent. In this condition of extraction (A8), total phenolic compounds (TPC) and antioxidant activity (AA) were determined. Additionally, this extract was used to evaluate their effect on antioxidant enzyme activities (superoxide dismutase (SOD) and catalase (CAT)) as well as lipid peroxidation (LP) and protein thiols level (PSH) in the liver and kidneys of normal and diabetic rats. As result, T. catharinensis extract presented TPC content of 23.34 mg EAG/g (equivalent gallic acid) and AA of 34.26 μmol Trolox/g. Phenolic acids (ferulic acid and coumaric acid) and flavonoids (quercetin, rutin and pinocembrin) could be recovered and identified by HPLC. This study indicated an important role of the T. catharinensis extract on free radical inactivation and on the antioxidant defense system in diabetic rats. In fact, the use of T. catharinensis extract restored the normal activity of SOD (p < 0.05) and suppressed malondialdehyde levels in liver and kidney tissues. Thus, the T. catharinensis extract, rich in phenolic compounds, can be responsible for the recover the enzymatic changes in the liver and kidney tissues provoked by diabetes in rats. In addition, the lipid peroxidation rate decreased in the diabetic rats treated with T. catharinensis.
Highlights
The use of plants by humans for nutritional and medicinal purposes has been historically reported [1,2,3]
The chromatographic profile of Tabernaemontana catharinensis leaves extract according to factorial design (A1 to A8) demonstrates the presence of quercetin, rutin, ferulic acid, coumaric acid and pinocembrin
Ethanol can be considered the most suitable solvent for quercetin, rutin, ferulic acid and coumaric acid extraction from Tabernaemontana catharinensis leaves when compared to ethyl acetate
Summary
The use of plants by humans for nutritional and medicinal purposes has been historically reported [1,2,3]. The importance of natural products is clearly recognized [4,5] and their challenges include extraction [6] and identification of chemical composition [2,6]. The potential applications of these bioactive compounds need to be consolidated in diverse areas such as in food [7,8,9], chemical and pharmaceutical [4,5,6] industries. Nature, accompanied by its great variability of species, consists of an expressive source of chemical compounds known as secondary metabolites with great potential in the development of Molecules 2020, 25, 2391; doi:10.3390/molecules25102391 www.mdpi.com/journal/molecules. Phenolics are phytochemical compounds, which present themselves as the most important group in natural products [11]. The phenolic compounds act as antioxidant and can be effective in preventing free radical formation by scavenging them and suppressing the oxidative stress, which is responsible for the induction of many chronic and degenerative diseases [1,4,11,12,13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
