Journal of Advances in Food Science & Technology

Introduction: Indigenous leafy vegetables are important sources of nutrients and bioactive compounds that contribute to food security and health promotion. This study aimed to evaluate the proximate and phytochemical composition of selected indigenous leafy vegetables from Southeastern Nigeria and to characterise their nutritional and pharmacognostic variability using multivariate statistical approaches.

Methods: Fresh leaves of Telfairia occidentalis, Amaranthus viridis, Solanum melongena, Ocimum gratissimum, and Gongronema latifolium were analysed using standard AOAC methods for proximate composition and established procedures for phytochemical determination. Principal component analysis (PCA), hierarchical cluster analysis (HCA), heatmap visualisation, and Pearson correlation analysis were applied to assess compositional relationships among the vegetables.

Results: Significant differences (p < 0.05) were observed in both proximate and phytochemical parameters. Moisture was the predominant proximate component, ranging from 38.47-55.06%FW, while protein content ranged from 10.63-25.37%DW, with Amaranthus viridis recording the highest value. Ash content varied between 8.79 and 13.99%, whereas fat, fibre, and carbohydrate contents ranged from 2.90-5.83%DW, 7.62-9.46%DW, and 6.02-18.57%DW, respectively. Phytochemical analysis revealed substantial variability among the vegetables. Solanum melongena exhibited the highest alkaloid (4.14 mg/g DW), flavonoid (5.71 mg QE/g DW), and total phenol (10.85 mg GAE/g DW) contents, while Ocimum gratissimum recorded the highest terpene (3.55 %DW) and glycoside (11.43 %DW) concentrations. Gongronema latifolium was distinguished by exceptionally high saponin (31.20 %DW) and tannin (26.58 mg TAE/g DW) contents. PCA of proximate and phytochemical datasets showed that the first two principal components accounted for 87.08% and 82.12% of the total variance, respectively. HCA and heatmap analyses further revealed distinct clustering patterns among the vegetables based on their nutritional and phytochemical attributes.

Conclusion: The findings demonstrate that the investigated vegetables possess complementary                      nutritional and pharmacognostic profiles, supporting their utilisation as functional foods, nutraceutical resources, and valuable components of dietary diversification strategies aimed at improving food and nutrition security.