Nutritional and Antioxidant Evaluation and Effect of Eggplant Consumption on Anthropometric and Hematologic Parameters in Wistar Rats

The aim of the present study was to evaluate the nutritional quality of green and purple eggplant, their antioxidant activity and their nutritional efficacy on Wistar rats. For nutritional quality, the parameters measured are dry matter, protein, lipid, ash, carbohydrate, iron, phosphorus, calcium, magnesium and energy content. For antioxidant activity, the parameters measured are 50% DDPH free radical inhibition concentration and total polyphenol content. Nutritional efficacy was evaluated in rats fed the control diet and in rats fed the three treated diets containing eggplant meal obtained by replacing 5%, 10%, and 15% of the control diet. The parameters measured are the amount consumed, the weight of the animal and target organs, and hematologic parameters. The results of the nutritional analysis show the following values: 13.31% protein, 2.66% lipids, 0.84% calcium, 0.12% magnesium, 0.43% phosphorus for the Solanum aethiopicum L. species and 13.47% protein, 3.66% lipids, 0.36% calcium, 0.22% magnesium, 0.35% phosphorus for the Solanum melongena L. species. In terms of antioxidant activity, we obtained DDPH inhibition percentages of 40.28 mg/ml for Solanum aethiopicum L. and 12.42 mg/ml for Solanum melongena L., respectively. Finally, hematologic and anthropometric tests showed that for the different diets used, weight loss and an increase in hematologic parameters were observed in the rats tested. This study showed that eggplant has interesting nutritional characteristics and antioxidant activity, contributing to an increase in weight and anthropometric parameters.

Chemical Characterization and Anti-Radical Activity of Fruits and Vegetables Commonly Consumed in Brazzaville

The objective of this study was to analyze ten (10) species of edible vegetables and nine (9) fruit commonly found in Congo (Brazzaville) in order to determine their total polyphenol content (TPC) and total flavonoid content (TFC), and their antiradical activity by the method of 1,1-diphenyl-2-picrylhydrazyl (DPPH). The results obtained showed that the highest TPC and TFC were found, on the one hand, in the extracts of four species of vegetables, i.e. Ipomoea batatas L. (536.02 ± 0.01 mg of GAE/100 g DW;486.46 ± 0.10 mg of QtE/100 g DW), Cucurbita pepo (533.60 ± 0.05 mg of GAE/100 g DW;303.72 ± 0 mg of QtE/100 g DW), Hibiscus sabdariffa (421.02 ± 0.015 mg of GAE/100 g DW;243.49 ± 0.10 mg of QtE/100 g DW), Solanum negrum 1 (412.10 ± 0.05 mg of GAE/100 g DW;292.10 ± 0.14 mg of QtE/100 g of DW) and, on the other hand, in the extracts of two species of fruit, i.e. Chrysophyllum lacourtianum (532.79 ± 0.19 mg of GAE/100 g of DW;380.55 ± 0.10 mg of QtE/100 g of DW) and seeds of Aframomum alboviolaceum (469.38 ± 0.28 mg of GAE/100 g DW;107.27 ± 0.10 mg of QtE/100 g DW). The lowest TPC and TFC were obtained with the extracts of Brassica campestris and of Spinacia oleracea, respectively 97.78 ± 0.17 GAE mg/100 g DW and 27.52 ± 0.10 QtE mg/100 g DW. The extract of the Saba senegalensis pulp had the lowest TPC and TFC. In addition, the highest antiradical activity was observed with extracts from vegetables and fruit with high TPC and TFC. The results indicate that these vegetables and fruit could be potential sources of the phenolic compounds and the biomolecules having several biological activities. Thus, their consumption might be an alternative in the prevention of chronic diseases.

Hypotensive Effects and Phytochemical Profile of Aqueous Extract and Fractions of Desmodium velutinun Leaves (Willd) D. C. (Fabaceae) in the Rat

Desmodium velutinum (D. velutinum) is a plant of the family Fabaceae used in traditional Congolese medicine for the treatment of high blood pressure (HBP) or hypertension (HT). The present work evaluated the hypotensive activity and determined the phytochemical profile of the aqueous extract and fractions of Desmodium velutinun (Willd) D. C. (Fabaceae) in the rat. The hypotensive effect of the aqueous extract and different fractions (F1, F2, F3 and F4) was evaluated at the dose of 2.5 mg/kg in normotensive rats anesthetized with 15% urethane at 1.5 g/kg, i.p. (intraperitoneally). Our results showed that the F3 fraction after administration caused a significant decrease in blood pressure and heart rate which remained higher than that of the aqueous extract and fractions (F1, F2 and F4). The richness in polyphenolic and flavonoid compounds as well as the separating capacity of the eluent used within the F3 fraction clearly justifies the beneficial effects of the latter on blood pressure and heart rate compared with the extract and fractions (F1, F2 and F4). In a second part we carried out the qualitative (thin-layer chromatography) and quantitative (total polyphenols and flavonoids determination) analysis. The chemical compounds remained dominated by the polyphenolic and flavonoid groups, the content of total polyphenols and total flavonoids meets the following increasing order: (extract, F1, F2, F3 and F4). The results obtained could certify the use of Desmodium velutinun in traditional Congolese medicine.