Asian Journal of Food Research and Nutrition

Aims: The study aimed to conduct a comparative analysis of the phytochemical and protein profiles of black beans and kidney beans to better understand their distinct nutritional properties and health benefits.

Study Design: This was a comparative, in vitro study focusing on the biochemical analysis of two different bean varieties.

Place and Duration of Study: Institute of Innovative Learning and Research Academy, Indore, Madhya Pradesh, India: January 2025 – February 2025.

Methodology: Kidney and black bean extracts were prepared and analyzed for their phytochemical content using qualitative tests for flavonoids, terpenoids, glycosides, saponins, tannins, phenols, steroids, alkaloids, and anthocyanins. Total antioxidant capacity (TAC) was measured using the phosphomolybdate assay, with results expressed as Ascorbic Acid Equivalent (AAE). Protein concentration was quantified using the Folin-Lowry method, and protein profiles were analyzed via SDS-PAGE to determine molecular weight ranges and diversity.

Results: Black bean extract demonstrated a higher total protein concentration (38.7 mg/ml) compared to kidney bean extract (33.7 mg/ml). The TAC was also superior in black beans (0.93 mg AAE/ml) versus kidney beans (0.74 mg AAE/ml). Phytochemical analysis showed that black beans were richer in flavonoids and anthocyanins, while kidney beans contained more terpenoids, glycosides, and steroids. SDS-PAGE revealed a greater diversity of proteins in kidney beans, with five distinct bands compared to three in black beans.

Conclusion: Both black and kidney beans are valuable nutrient sources with complementary benefits. Black beans excel in their antioxidant capacity and total protein content, while kidney beans are distinguished by a wider variety of protein types. This research provides a basis for future studies and emphasizes the importance of dietary diversity.