Phenolic and Mineral Characteristics of Seed Coats and Kernels from 24 Species from Raipur Area, India

Abstract

Aims: The objective of the present work is the investigation of the physicochemical characteristics of seed coats and kernels from 24 species with medicinal and food applications. Methodology: Seeds from 24 species (2 herbs, 11 vines and 11 trees), belonging to 13 families, were sampled in Raipur (India) in 2017. The collected seeds were dried and weighed, after which seed coats were manually peeled and separately weighed. Phenolic and mineral contents in the seed coats and kernels were analyzed by spectrophotometric and X-ray fluorescence (XRF) techniques, respectively. Results: The seed coat fraction represented from 12% to 95% of the seed mass, depending on the species. The concentrations of total polyphenols, flavonoids and minerals in the seed coats varied from 1800 to 32300 mg/kg, from 1200 to 26900 mg/kg, and from 5876 to 36499 mg/kg, respectively. In the seed kernels, TPh, Fla and minerals ranged from 780 to 31760 mg/kg, from 300 to 12020 mg/kg, and from 12595 to 40810 mg/kg, respectively. P, S, K, Mg, Ca and Fe were found to be the main macro- and micro-elements. Seed coats from Loganiaceae, Phyllanthaceae, Lauraceae and Rutaceae families featured the highest total polyphenol contents, and those from Lauraceae and Rutaceae families showed the highest flavonoid concentrations. The highest total mineral contents corresponded to seed coats from Lauraceae, Rutaceae and Euphorbiaceae families. Conclusion: Indian-laurel and curry tree stand out as promising phytochemical and nutrient sources.