Open AccessElicitation kinetics of phenolics in common bean ( Phaseolus vulgaris ) sprouts by thermal treatments
Author(s) -
Ampofo Josephine,
Ngadi Michael,
Ramaswamy Hosahalli S.
Publication year - 2020
Publication title -
legume science
Language(s) - English
Resource type - Journals
ISSN - 2639-6181
DOI - 10.1002/leg3.56
Subject(s) - phenylpropanoid , phaseolus , chemistry , catalase , food science , peroxidase , activation energy , guaiacol , sprouting , malondialdehyde , phenylalanine , hydrogen peroxide , phenylalanine ammonia lyase , biochemistry , botany , antioxidant , enzyme , organic chemistry , biosynthesis , biology , amino acid
Abstract Phenolics are plant secondary metabolites with numerous health benefits, produced via the phenylpropanoid pathway in plants in response to environmental conditions. In this study, the mathematical relationship between thermal elicitation (25°C, 30°C, 35°C, and 40°C) of phenolic compounds through the accumulation of oxidative stress markers (hydrogen peroxide [H 2 O 2 ], malondialdehyde [MDA], catalase [CAT], and guaiacol peroxidase [GPX]) and activation of phenylpropanoid triggering enzymes (phenylalanine ammonia‐lyase [PAL] and tyrosine ammonia‐lyase [TAL]) was kinetically modeled at different sprouting stages of common bean. The rate of H 2 O 2 and MDA formation showed an increasing trend with an increase in sprouting temperature. However, activation rates of CAT, GPX, PAL, and TAL were highest at 30°C, after which there were significant reductions. Also, activation rate of PAL was lower as compared with TAL, which was further established with its low activation energy E a value of 150 kJ/mol compared with TAL (221 kJ/mol). Also, activation energy values for total phenolic acids (30.4 kJ/mol) and flavonoids (64.0 kJ/mol) showed that they required less energy for formation during sprouting, compared with anthocyanins (209 kJ/mol), with the activation energy results obtained from their estimated kinetic rate constants and production percentages. Thus, manipulation of sprouting temperature can increase the potential use of common beans as natural functional foods with improved health benefits.