Citation: D., D.D.; Padhi, S.R.; Gore, P.G.; Tripathi, K.; Katral, A.; Chandora, R.; Abhishek, G.J.; Kondal, V.; Singh, R.; Bharadwaj, R.; et al. Nutritional Potential of Adzuki Bean Germplasm and Mining Nutri-Dense Accessions through Multivariate Analysis. Foods 2023, 12, 4159. https://doi.org/10.3390/ foods12224159 Academic Editors: Weiqun Wang and Fook Yee Chye Received: 14 August 2023 Revised: 30 October 2023 Accepted: 11 November 2023 Published: 17 November 2023 Copyright: © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). foods Article Nutritional Potential of Adzuki Bean Germplasm and Mining Nutri-Dense Accessions through Multivariate Analysis Deepika D. D. 1,2 , Siddhant Ranjan Padhi 1,2 , Padmavati G. Gore 2 , Kuldeep Tripathi 2 , Ashvinkumar Katral 1 , Rahul Chandora 2 , G. J. Abhishek 1,2 , Vishal Kondal 2 , Rakesh Singh 2 , Rakesh Bharadwaj 2, *, Kailash C. Bhatt 2,3, *, Jai Chand Rana 4 and Amritbir Riar 5 1 The Graduate School, ICAR-Indian Agricultural Research Institute, PUSA, New Delhi 110012, India; dddeepika.dd@gmail.com (D.D.D.); siddhant.padhi1@gmail.com (S.R.P.); ashokgkatral@gmail.com (A.K.); golsarabhishek50@gmail.com (G.J.A.) 2 ICAR—National Bureau of Plant Genetic Resource, Pusa, New Delhi 110012, India; padmavati.gore@icar.gov.in (P.G.G.); kuldeep.tripathi@icar.gov.in (K.T.); rahul1@icar.gov.in (R.C.); vishalkondal4@gmail.com (V.K.); rakesh.singh2@icar.gov.in (R.S.) 3 Division of Plant Exploration and Germplasm Collection, ICAR—National Bureau of Plant Genetic Resources, Pusa, New Delhi 110012, India 4 The Alliance of Bioversity International & CIAT—India Office, New Delhi 110012, India; j.rana@cgiar.org 5 Department of International Cooperation, Research Institute of Organic Agriculture FiBL, 5070 Frick, Switzerland; amritbir.riar@fibl.org * Correspondence: rakesh.bhardwaj1@icar.gov.in (R.B.); kailash.bhatt@icar.gov.in (K.C.B.) Abstract: The adzuki bean (Vigna angularis), known for its rich nutritional composition, holds significant promise in addressing food and nutritional security, particularly for low socioeconomic classes and the predominantly vegetarian and vegan populations worldwide. In this study, we assessed a total of 100 diverse adzuki bean accessions, analyzing essential nutritional compounds using AOAC’s official analysis procedures and other widely accepted standard techniques. Our analysis of variance revealed significant genotype variations for all the traits studied. The variability range among different traits was as follows: moisture: 7.5–13.3 g/100 g, ash: 1.8–4.2 g/100 g, protein: 18.0–23.9 g/100 g, starch: 31.0–43.9 g/100 g, total soluble sugar: 3.0–8.2 g/100 g, phytic acid: 0.65–1.43 g/100 g, phenol: 0.01–0.59 g/100 g, antioxidant: 11.4–19.7 mg/100 g GAE. Noteworthy accessions included IC341955 and EC15256, exhibiting very high protein content, while IC341957 and IC341955 showed increased antioxidant activity. To understand intertrait relationships, we computed correlation coefficients between the traits. Principal Component Analysis (PCA) revealed that the first four principal components contributed to 63.6% of the variation. Further, hierarchical cluster analysis (HCA) identified nutri-dense accessions, such as IC360533, characterized by high ash (>4.2 g/100 g) and protein (>23.4 g/100 g) content and low phytic acid (0.652 g/100 g). These promising compositions provide practical support for the development of high-value food and feed varieties using effective breeding strategies, ultimately contributing to improved global food security. Keywords: underutilized legume; nutritional composition; variability; multivariate analysis; ANOVA 1. Introduction Legumes are essential for meeting the dietary and nutritional needs of both people and animals. The global population is projected to increase by 170% by 2050, posing enormous challenges to the global community in ensuring secure and safe food supplies [1]. Legumes represent a unique food crop group aligning with sustainable goals while providing a substantial amount of essential nutrients. Adzuki beans, in particular, stand out as highly resilient crops, showcasing remarkable adaptability to various growing conditions in both temperate and semitropical areas. They demonstrate a capacity to thrive even in nutrient- deficient soils. Given their seeds’ high-quality protein content, low carbon and water Foods 2023, 12, 4159. https://doi.org/10.3390/foods12224159 https://www.mdpi.com/journal/foods