Effects of Bromelain and Trypsin Hydrolysis on the Phytochemical Content, Antioxidant Activity, and Antibacterial Activity of Roasted Butterfly Pea Seeds

Abstract

Butterfly pea (Clitoria ternatea L.) is a traditional medicinal and edible herb, whose health-promoting benefits have been attributed to its phenolic constituents. In this study, the effects of enzymatic hydrolysis on total phenolic content (TPC) and total flavonoid content (TFC), antioxidant (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP)) and antibacterial activities of raw and roasted (200 °C, 10–20 min) butterfly pea seeds were investigated. Roasting reduced the yield of seed aqueous extracts, but it increased the TPC and FRAP values, hence the reducing ability, of the extracts. Bromelain hydrolysis enhanced the TPC and TFC of the roasted seeds up to 2- and 18-fold higher, respectively. Trypsin hydrolysis drastically increased the TPC, but not TFC, of roasted seeds; trypsin-hydrolyzed, 20 min roasted sample had the highest TPC (54.07 μg gallic acid equivalent (GAE)/mg) among all samples. Bromelain hydrolysis significantly improved the antioxidant activity of the roasted seed samples, where the antioxidant activity of bromelain-hydrolyzed, 20 min roasted sample was about 50% greater than the non-hydrolyzed 20 min roasted sample. Trypsin hydrolysis raised the FRAP values of the 20 min roasted sample to 70.28 mg Fe(II) equivalent/g, the highest among all samples. Nevertheless, trypsin only weakly elevated the ABTS scavenging activity of the roasted samples, showing no enhancement of the DPPH scavenging activity. On the other hand, only bromelain hydrolysates of raw and 10 min roasted seeds were active against Staphylococcus aureus. Taken together, bromelain hydrolysis can be used to enhance the extractable phytochemical contents and antioxidant activity of roasted butterfly pea seeds.

Evaluation of the Antioxidant and Antimicrobial Activities of Porcine Liver Protein Hydrolysates Obtained Using Alcalase, Bromelain, and Papain

“…Bromelain was the enzyme that resulted in hydrolysates with the highest antimicrobial activity, followed by alcalase. A similar behavior was observed by Ee et al [20], who noticed higher activities of bromelain and no activity against Gram-negative bacteria.…”

“…The use of different enzymes and hydrolysis times are crucial in the production of antibacterial peptides [20]. The activity of these antimicrobial peptides allows the selective disruption of cell membranes, which leads to membrane permeabilization, depolarization, dissipation of electrochemical gradients, and eventual cell death [54].…”

“…However, scarce information is available on the antioxidant and antimicrobial activities of hydrolysates and their fractions obtained with bromelain. These enzymes are less known and are usually used in the enzymatic hydrolysis of legume seed extracts [20].…”

Characterization, antioxidant, ACE inhibition and toxicity evaluations of palm kernel cake-derived Alcalase® hydrolysate

“…• -) free radical scavenging and oxygen radical absorbing capacity (ORAC) assays with slight modification (Ee et al, 2012(Ee et al, , 2019.…”

Antioxidant-rich Clitoria ternatea L. flower and its benefits in improving murine reproductive performance

“…DPPH free radical scavenging assay was carried out according to a procedure described by Ee et al (2019) with slight modification. DPPH radical solution was prepared freshly by mixing 10 mg of DPPH in 25 mL of 80% (v/v) aqueous methanol.…”