Identification and Quantification of Phenolic Compounds and Antioxidant Activity in Cowpeas of BRS Xiquexique Cultivar

Abstract

Cowpea (Vigna unguiculata [L.] Walp.) is one of the most important legumes produced in tropical and subtropical regions throughout the world, especially in the developing countries in Africa, Latin America, and Asia. It is the main source of protein, calories, dietary fiber, minerals, and vitamins for a large segment of the world population. Cowpea is also a potential functional food with a range of bioactive compounds, including phenolic compounds. This legume is grown mainly in the North and Northeast regions of Brazil, but is also consumed in other regions, and is thus important for the farmers who depend on this crop for income. This study identified and quantified phenolic compounds in the cowpea cultivar BRS Xiquexique. Such quantification reveals the functional characteristics of cowpeas, mainly as a source of antioxidants, which will be essential to add value to this food and to expand its forms of consumption. The extracts were analyzed using an HPLC model LC-20AT, equipped with a manual injector. For the HPLC analysis, standard solutions were prepared with pure phenolic acids such as gallic acid, quercetin, caffeic acid, chlorogenic acid, ferulic acid, p-coumaric acid, catechin, and epicatechin. The major phenolic compounds identified were catechin (2.07± 0.329 mg 100 g-1), epicatechin (0.48 ± 0.130 mg 100 g-1), gallic acid (67.19 ± 6.200 mg 100 g-1), ferulic acid (32.07 ± 0.753 mg 100 g-1), and chlorogenic acid (3.08 ± 0.489 mg 100 g-1). We observed that the BRS Xiquexique cultivar contains functional phenolic compounds, especially gallic acid and ferulic acid, demonstrating the antioxidant potential of cowpea.

Mineral content, phenolic compounds and bioactive amines of cheese bread enriched with cowpea

“…According to Moreira-Araújo et al (2018) among the phenolic compounds identified in cowpea, stood out the catechin (2.07 to 6.48 mg/100g), epicatechin (0.48 to 8.67 mg/100g), gallic acid (45.4 to 93.4 mg/100g), ferulic acid (11.1 to 32.07 mg/100g) and chlorogenic acid (0.59 to 3.08 mg/100g).…”

Drought stress effect on polyphenolic content and antioxidant capacity of cowpea pods and seeds

“…Besides, in the specific case of immature seeds from this genotype, it was observed an increase of all parameters under water stress against the control group suggesting that this genotype is more tolerant to drought stress and can be a good choice in the climate changes context and in regions with water scarcity. To confirm this hypothesis, it would be important in a near future to fingerprint, in different water‐deficit stresses, the major individual phenolic compounds previously identified in cowpea, namely catechin, epicatechin, gallic acid, ferulic acid and chlorogenic acid (Moreira‐Araújo et al., 2018).…”

“…In contrast, Moreira‐Araújo et al. (2018) classified cowpea as a moderate crop in relation to phenolic content. Probably, these differences can be explained by the interference of genetic and environmental factors, as well as factors inherent to extraction methodology (as the solvent used).…”

Liquiritin elicitation can increase the content of medicinally important glucosinolates and phenolic compounds in Chinese kale plants

“…To this end, the direct infusion of the corresponding standard solutions for GLSs and PHs was performed. GLSs were quantified using sinigrin (Sigma) as standard compound, whereas glycosylated and acylated flavonoids were quantified as quercetin‐3‐rutinoside, and hydroxycinnamic acids as sinapic acid, as recommended by Moreira‐Araújo et al . Each standard solution prepared at a concentration of 10 mg mL −1 of 70% (v/v) methanol was infused separately into the mass spectrometer at a flow rate of 5 mL min −1 , to optimize parameters such as declustering potential, focusing potential and entrance potential.…”