In recent years, with the increasing awareness of health concerns and environment protection needs, there is a growing interest for consumers to choose plant-based food diets compared with those made from animal origin. Pumpkin seed is an excellent dietary source for protein, oil, and some essential micronutrients. Raw pumpkin seed may have a compromised flavor, color, as well as digestibility. Therefore, the objective of present study is to study the influence of roasting (120, 160, and 200°C for 10 min) on the phenolics content, flavonoids content, antioxidant property, fatty acids, and volatile matter composition, as well as protein profile of pumpkin seeds. Our results indicated that, total phenolic compounds, total flavonoids content, as a consequence, total antioxidant capacity increased as the roasting temperature increased. Maillard reaction products and lipid peroxidation products were identified, especially from those pumpkin seeds roasted at high temperature. In the meantime, the composition and content of fatty acids did not change significantly after roasting. The results of electrophoresis and particle size analysis showed that the optimum roasting temperature was 160°C to obtain protein with better nutritional quality. The findings of this study may contribute to the utilization of pumpkin seed component in plant-based diets with increased nutritional quality.
Zinc is a crucial micronutrient for maintaining body immune system and metabolism function. However, insufficient intake from diet may lead to zinc deficiency and impair normal body function. In addition, conventional zinc salts supplementation has the disadvantage of low bioavailability since the zinc ions may be easily chelated by dietary fiber or phytate commonly found in diets rich in plants, and form precipitates that cannot be absorbed. Therefore, the objective of the present study is to prepare pumpkin seed derived peptides and to evaluate the effect of structure and surface properties on the zinc binding behavior of the pumpkin seed protein hydrolysate (PSPH), as well as their gastrointestinal stability. Briefly, different PSPHs were prepared using enzymatic hydrolysis method with bromelain, papain, flavourzyme, alcalase, and pepsin. The particle size, zeta potential, surface hydrophobicity, degree of hydrolysis, ATR-FTIR spectra, and zinc binding capacity were determined. The representative samples were chosen to characterize the binding energy and surface morphology of PSPH-Zn. At last, the in vitro gastrointestinal stability of PSPH and PSPH-Zn were evaluated. Our results showed that peptides hydrolyzed by papain had the largest average molecular weight, smallest particle size, highest hydrophobicity, and the greatest zinc binding capacity. Zinc showed better gastrointestinal stability in PSPHs chelates than in its salt. Meanwhile, PSPH-Zn with higher zinc binding capacity showed better stability. The result of this study indicated pumpkin seed hydrolyzed by papain may be used as a potential source for zinc fortification. The findings in this study may provide important implications for developing plant-based zinc chelating peptides.
In this study, pumpkin seeds peptide was purified, characterized, and evaluated for their zinc‐chelating capability, as well as in vitro bioaccessibility and transportation. Raw pumpkin seeds protein hydrolysate (PSPH) was produced by papain hydrolysis. The peptide fractions with the highest zinc‐chelating abilities were purified using immobilized metal affinity chromatography (IMAC) followed by gel filtration chromatography (GF). Eight peptides were identified, two of which with the lowest molecular weights were synthesized (RPKHPLK and RPKHPLSHDL) for determining potential bioaccessibility and bioavailability. Our results showed that the gastrointestinal stability of RPKHPLK‐Zn and RPKHPLSHDL‐Zn was higher than that of inorganic zinc salts in the simulated gastrointestinal tract model. Furthermore, the influence of the peptide zinc chelates on zinc transport was explored in vitro using Caco‐2 cell monolayer model. It was also shown that both RPKHPLK‐Zn and RPKHPLSHDL‐Zn could increase zinc transport rate and may be used to facilitate effective zinc absorption. The result of this study may provide important implications for developing plant protein foods with higher nutritional value. Practical Application As a potential alternative protein source, pumpkin seeds may find promising applications in plant‐based foods and drinks to meet the growing market for nonanimal foods. In this study, pumpkin seed protein peptides were prepared and purified, and the zinc‐chelating peptides were identified and evaluated for the abilities to promote the uptake of zinc. This type of mineral peptide chelates could be incorporated into plant‐based foods to increase mineral contents, which is significantly higher in foods originated from animals. The result of our study may provide important information for food industry to increase the nutritional value of plant‐based foods.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.