Sequence Identification of Bioactive Peptides from Amaranth Seed Proteins (Amaranthus hypochondriacus spp.)

Abstract

Amaranthus hypochondriacus spp. is a commonly grown cereal in Latin America, known for its high protein content. The objective of this study was to separate and identify bioactive peptides found in amaranth seeds through enzymatically-assisted hydrolysis using alcalase and flavourzyme. Hydrolysis was carried out for each enzyme separately and compared to two-step continuous process where both enzymes were combined. The biological activity of the resulting three hydrolysates was analyzed, finding, in general, higher bioactive potential of the hydrolysate obtained in a continuous process (combined enzymes). Its fractions were separated by RP-HPLC, and their bioactivity was analyzed. In particular, two fractions showed the highest biological activity as ACE inhibitors with IC50 at 0.158 and 0.134, thrombin inhibitors with IC50 of 167 and 155, and antioxidants in ABTS assay with SC50 at 1.375 and 0.992 mg/L, respectively. Further sequence analysis of the bioactive peptides was carried out using MALDI-TOF, which identified amino acid chains that have not been reported as bioactive so far. Bibliographic survey allowed identification of similarities between peptides reported in amaranth and other proteins. In conclusion, amaranth proteins are a potential source of peptides with multifunctional activity.

Amaranth as a Source of Antihypertensive Peptides

“…Their results showed that action of both enzymes affords hydrolysates with high antioxidant, antithrombotic and antihypertensive activity. It should be noted that the values obtained by Ayala-Niño et al. (2019a) are not very different from those reported by other authors for hydrolysates with alcalase ( Fritz et al., 2011 ; Ramírez-Torres et al., 2017 ).…”

“… Ayala-Niño et al. (2019a) analyzed the profile of peptides obtained by the consecutive hydrolysis of a protein isolate from A. hypochondriacus with alcalase and flavourzyme.…”

Enzymatic hydrolysis of black cricket (Gryllus assimilis) proteins positively affects their antioxidant properties

“…The antioxidant activities obtained in our study were lower than the antioxidant properties of cricket ( Amphiacusta annulipes ) protein hydrolyzed by gastrointestinal simulation, which presented IC 50 values of 19.1 and 7.4 µg/mL for the DPPH and ABTS radical scavenging activity, respectively (Zielińska, Karaś, & Jakubczyk, 2017). In contrast, the ABTS radical scavenging activity exhibited by the BCPC hydrolysate was higher than obtained for peptides from amaranth seed proteins that presented IC 50 ranging from 0.992 to 6.931 mg/mL (Ayala‐Niño et al., 2019).…”

Analytical Technology in Nutrition Analysis

“…This Special Issue has received remarkably positive feedback, with many contributions submitted by numerous geographically diverse scientists, resulting in a collection of 10 publications, including two exhaustive review articles [9][10][11][12][13][14][15][16][17][18]. Among the contributing authors, authors can be found from Asia (China, India, and Uzbekistan), Europe (Spain), South America (Brazil and Chile) and North America (Mexico).…”

“…Another article described the multifunctional activity of amaranth (Amaranthus hypochondriacus spp.) proteins, opening the possibility that amaranth hydrolyzed with alcalase and flavourzyme to be used as a value-added ingredient with multi-functional bioactive properties [10]. Another article aimed to find an efficient extraction method and investigate some of physical and chemical parameters, like water solubility, emulsification, foaming properties, and oil-holding capacity of obtained scorpion proteins.…”