Tailoring the Health-Promoting Potential of Protein Hydrolysate Derived from Fish Wastes and Flavonoids from Yellow Onion Skins: From Binding Mechanisms to Microencapsulated Functional Ingredients

Abstract

This study focuses on combining different bioprocessing tools in order to develop an in-depth engineering approach for enhancing the biological properties of two valuable food by-products, namely fish waste and yellow onion skins, in a single new bioactive formulation. Bone tissue from phytophagous carp (Hypophthalmichthys molitrix) was used to obtain bioactive peptides through papain-assisted hydrolysis. The peptides with molecular weight lower than 3 kDa were characterized through MALDI-ToF/ToF mass spectrometry and bioinformatics tools. As a prerequisite for microencapsulation, the ability of these peptides to bind the flavonoids extracted from yellow onion skins was further tested through fluorescence quenching measurements. The results obtained demonstrate a considerable binding potency with a binding value of 106 and also the presence of one single or one class of binding site during the interaction process of flavonoids with peptides, in which the main forces involved are hydrogen bonds and van der Waals interactions. In the freeze-drying microencapsulation process, an efficiency for total flavonoids of 88.68 ± 2.37% was obtained, considering the total flavonoids and total polyphenols from the powder of 75.72 ± 2.58 quercetin equivalents/g dry weight (DW) and 97.32 ± 2.80 gallic acid equivalents/g DW, respectively. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test on the L929 cell line cultivated in the presence of different concentrations of microencapsulated samples (0.05–1.5 mg/mL) proved no sign of cytotoxicity, the cell viability being over 80% for all the samples.

Effect of Fish Bone Bioactive Peptides on Oxidative, Inflammatory and Pigmentation Processes Triggered by UVB Irradiation in Skin Cells

“…Fourteen bioactive peptides were identified in FBBP preparation, in a previous study, by matching the peaks of matrix assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrum, corresponding to 0–3000 mass-to-charge ratios ( m / z ), and the amino acid sequences provided by simulated papain cleavage of type I collagen, the most abundant protein in bone [ 17 ]. In the present study, we correlated the calculated MW and isoelectric point (pI) values of the collagenic peptides ranging 0–2000 m / z and presenting the characteristic -Gly-X-Y- repetitive sequence, to the chromatography data, in particular the ion exchange and RP-HPLC results, as well as to their antiradical activity.…”

“…For the identification of collagenic peptides with high antioxidant activity in FBBP preparation, an analysis of correlation between ion exchange chromatography and free radicals scavenging data obtained as described above was performed; the peptides were isolated by MALDI-ToF mass spectrometry analysis in the range of 0–2000 m / z ; and their amino acid sequences, pI and MW were predicted using Uniprot database information, as previously reported [ 17 ].…”

“…Studies on the enzymatic hydrolysis of its waste tissues discarded after industrial processing have mainly focused on skin [ 13 ] and muscle [ 14 , 15 , 16 ]. Papain treatment of discarded H. molitrix bones followed by centrifugal ultrafiltration resulted in a peptides mixture containing low MW compounds useful as dietary supplement after microencapsulation with flavonoids [ 17 ]. Preliminary data on the preparation’s ability to stimulate cell adhesion and migration in human keratinocytes culture were also reported, as the main processes during skin wound healing [ 18 ], which required further investigations.…”

Light and Autofluorescence, Multitasking Features in Living Organisms

“…The assessment of the color maintenance through the analysis of chromaticity parameters is used along with other techniques to estimate the effectiveness of these strategies. When proteinaceous substrates are used, their own fluorescence has also been used to monitor their association with anthocyanin molecules [99][100][101][102].…”

Bio-Based Formulations for Sustainable Applications in Agri-Food-Pharma

“…In another study, Grigore-Gurgu et al [15] used microencapsulation to enhance the biological properties of two bioactive components (flavonoids and peptides) in a single formulation. They microencapsulated flavonoids extracted from yellow onion skin using papain-hydrolysed peptides extracted from bone tissue from phytophagous carp (Hypophthalmichthys molitrix).…”