Potential of Chilean Native Corn (Zea mays L.) Accessions as Natural Sources of Phenolic Antioxidants and in Vitro Bioactivity for Hyperglycemia and Hypertension Management

• Published in: Journal of agricultural and food chemistry 2013-11, Vol.61 (46), p.10995-11007
• Main Authors: González-Muñoz, Adrian, Quesille-Villalobos, Ana Maria, Fuentealba, Claudia, Shetty, Kalidas, Gálvez Ranilla, Lena
• Format: Article
• Language: English
• Subjects: alpha-amylase; alpha-Amylases - antagonists & inhibitors; alpha-glucosidase; Angiotensin-Converting Enzyme Inhibitors - chemistry; Antihypertensive Agents - chemistry; antioxidant activity; antioxidants; Antioxidants - chemistry; Biological and medical sciences; Chile; corn; Enzyme Inhibitors - chemistry; ferulic acid; Fundamental and applied biological sciences. Psychology; gallic acid; Glycoside Hydrolase Inhibitors; high performance liquid chromatography; hyperglycemia; hypertension; Hypoglycemic Agents - chemistry; peptidyl-dipeptidase A; Phenols - chemistry; Plant Extracts - administration & dosage; principal component analysis; seeds; vanillin; Zea mays; Zea mays - chemistry
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf403237p

Thirty-three Chilean corn accessions were screened for the first time regarding their phenolic profiles, total phenolic contents (TPC), antioxidant capacity (DPPH and ABTS), and in vitro inhibition against key enzymes relevant for hyperglycemia (α-amylase and α-glucosidase) and hypertension (angiotensin I-converting enzyme, ACE-I) in both free and cell wall-bound fractions. TPC varied from 132.2 to 262.5 mg of gallic acid equivalents/100g dry weight (DW), and around 88% of TPC and antioxidant capacity were found in the bound form. Vanillin, vanillic, protocatechuic, ferulic, and p-coumaric acids were detected by HPLC in free fractions, whereas ferulic and p-coumaric acids were found in the bound form. Pisankalla accession (red kernel) had the highest ferulic acid content (269.5 mg/100g DW). No α-amylase and ACE-I inhibition were found; however, all free fractions inhibited α-glucosidase (10.8–72.5%). Principal component analysis revealed that darker samples (free fraction) showed higher TPC and antioxidant capacity, while α-glucosidase inhibition was related to yellow-colored samples.