Antioxidant and Antimicrobial Activity of Porcine Liver Hydrolysates Using Flavourzyme

Antimicrobial peptides derived from food byproducts: Sources, production, purification, applications, and challenges

Food wastes can be a valuable reservoir of bioactive substances that can serve as natural preservatives in foods or as functional ingredients with potential health benefits. The antimicrobial properties of protein hydrolysates, especially antimicrobial peptides (AMPs) derived from food byproducts (FBs), have been extensively explored. These protein fragments are defined by their short length, low molecular weight, substantial content of hydrophobic and basic amino acids, and positive net charge. The intricate mechanisms by which these peptides exert their antimicrobial effects on microorganisms and pathogens have been elaborately described. This review also focuses on techniques for producing and purifying AMPs from diverse FBs, including seafood, livestock, poultry, plants, and dairy wastes. According to investigations, incorporating AMPs as additives and alternatives to chemical preservatives in food formulations and packaging materials has been pursued to enhance both consumer health and the shelf life of foods and their products. However, challenges associated with the utilization of AMPs derived from food waste depend on their interaction with the food matrix, acceptability, and commercial viability. Overall, AMPs can serve as alternative safe additives, thereby ensuring the safety and prolonging the storage duration of food products based on specific regulatory approvals as recommended by the respective safety authorities.

Identification and in vitro Characterization of Novel Antidiabetic Peptides Released Enzymatically from Peanut Protein

Bioactive peptides derived from proteins found in various foods provide significant health benefits, including regulating blood sugar levels by inhibiting carbohydrate-hydrolyzing enzymes. Hydrolysates of peanut protein were prepared using alcalase (AH) or trypsin (TH) to generate antidiabetic peptides with high activity against α-amylase (IC50 of 6.46 and 5.71 mg/mL) and α-glucosidase (IC50 of 6.30 and 5.57 mg/mL), as well as antiradical activity to scavenge DPPH• (IC50 of 4.18 and 3.12 mg/mL) and ABTS•+ (IC50 of 2.87 and 2.56 mg/mL), respectively. The bioactivities of hydrolysates were greatest in the ultrafiltration-generated F3 fraction (< 3 kDa). The most active fraction was TH-F3, which was purified by gel filtration chromatography to generate sub-fractions (SF). With IC50 values of 1.05 and 0.69 mg/mL, the F3-SF8 fraction was the most effective at inhibiting the activity of α-amylase and α-glucosidase, respectively. This fraction was further purified using RP-HPLC to generate sub-subfractions (SSF), the most active of which were F3-SF8-SSF9 and SSF10. The peptide sequences F3-SF8-SSF9 and SSF10 were determined using LC-MS/MS. Two novel antidiabetic peptides with the potential to inhibit α-amylase and α-glucosidase were identified, with the sequences Asp-Trp-Arg (476.22 Da, IC50 of 0.78, and 0.35 mg/mL) and Phe-Tyr (329.15 Da, IC50 of 0.91, and 0.41 mg/mL). These results suggest that peptides derived from peanut protein are attractive natural ingredients for diabetes management applications.

Valorization of porcine by-products: a combined process for protein hydrolysates and hydroxyapatite production

The meat industry generates large amounts of by-products that are costly to be treated and discarded ecologically; moreover, they could be used to extract high added-value compounds. In this work, we present an innovative combined process which allowed the parallel extraction of both organic and mineral compounds; more specifically protein hydrolysates and single-phase hydroxyapatite were obtained. The protein hydrolysates, extracted through an enzymatic hydrolysis with alcalase, showed a degree of hydrolysis of 53.3 ± 5.1%; moreover, they had a high protein content with peptides with molecular weight lower than 1.2 kDa. Their antioxidant activities, measured with ABTS and ORAC tests, were 21.1 ± 0.5 mg ascorbic acid equivalent/g of dry extract and 87.7 ± 6.3 mg Trolox equivalent/g of dry extract, respectively. Single-phase hydroxyapatite, obtained with a simple calcination at 700 °C on the residues of the hydrolysis process, showed a Ca/P ratio close to the stoichiometric one (1.65 vs. 1.67) and presented a nanometric structure. This study reports a simple and feasible process for the valorization of porcine by-products in a large-scale up generating products with potential applications for environment remediation, biomedicine, nutrition and catalysis/bioenergy.

Porcine placenta hydrolysate as an alternate functional food ingredient: In vitro antioxidant and antibacterial assessments

The production of bioactive peptides from animal-based raw materials highly depends on enzymatic hydrolysis. Porcine placenta is an underutilized biomass in Thailand's pig farms, yet it is still a source of proteins and beneficial compounds. Porcine placenta could be used as a protein substrate for the production of enzymatic hydrolysate, which could be employed as a functional food ingredient in the future. The goal of this study was to enzymatically produce porcine placenta hydrolysates (PPH) using three commercial enzymes (Alcalase, Flavouzyme, and papain) and evaluate their in vitro antioxidant and antibacterial activity. The degree of hydrolysis (DH) increased as the enzyme load and hydrolysis time increased, but the DH was governed by the enzyme class. The maximum DH was found after using 10% enzyme for 20 min of hydrolysis (36.60%, 31.40%, and 29.81% for Alcalase, Flavouzyme, and papain). Depending on the enzyme type and DH, peptides of various sizes (0.40-323.56 kDa) were detected in all PPH. PPH created with Alcalase had an excellent reducing capacity and metal chelating ability (p < 0.05), whereas PPH made with Flavourzyme and Papain had higher DPPH• and ABTS•+ inhibitory activities (p < 0.05). Papain-derived PPH also had a strong antibacterial effect against Staphylococcus aureus and Escherichia coli, with clear zone values of 17.20 mm and 14.00 mm, respectively (p < 0.05). When PPH was transported via a gastrointestinal tract model system, its antioxidative characteristics were altered. PPH's properties and bioactivities were thus influenced by the enzyme type, enzyme concentration, and hydrolysis time used. Therefore, PPH produced from porcine placenta can be categorized as an antioxidant and antibacterial alternative.