Bioactive peptides derived from plant origin by-products: Biological activities and techno-functional utilizations in food developments – A review

Highlights

• Protein recovery potentials of various plant by-products as bioactive peptides resources were reviewed.

• Chemical and biological properties of bioactive peptides were discussed.

• Plant by-product protein hydrolysates have wide range of applications.

• Plant based biologically active peptides as functional food ingredients have technological advantages in food developments.

• Future studies are needed on the further utilization attempts of bioactive peptides.

Abstract

Agro-industrial by-products containing considerable amounts of protein (10–50%) such as soybean meal, rice bran and coconut pulp are promising bioactive peptide sources with annual disposal rate of 800 million tons in the world. More recently, plant by-products rich in protein content have been studied under various prisms that include recovery techniques, peptide production methods, determination of technological benefits and functional properties, and their applications in foods. The researches in bioactive peptides provide evidence over the techno-functional properties and the health benefits are highly dependent upon their amino acid sequences, molecular weights, conformations and surface properties. Research findings compared bioactive properties of the obtained peptides with respect to their amino acid sequences and also reported that hydrophobic/hydrophilic properties have direct effect on both functional and health effects. In addition, the resultant properties of the peptides could be affected by the conducted extraction method (alkaline, enzymatic, ultrasound assisted, microwave assisted, etc.), extraction solvent, precipitation and purification techniques and even by the final drying process (spray, freeze, vacuum, etc.) which may alter molecular weights, conformations and surface properties. Latest studies have investigated solubility, emulsifying, foaming, water/oil holding capacity and surface properties and also antioxidant, antimicrobial, anticarcinogenic, hypocholesterolemic, antihypertensive, immunomodulatory and opioid activities of bioactive peptides obtained from plant by-products. Moreover, the application of the bioactive peptides into different food formulations has been a recent trend of functional food development. These bioactive peptides’ bitter taste and toxicity are possible challenges in some cases that need to be resolved before their wider utilization.

Introduction

Food processing industry generates high amounts of by-products causing environmental disposal problems along with additional significant outgoings. However, agro-industrial by-products have great potential to generate food additives which can be beneficial in terms of ensuring the global food sustainability (Gençdağ, Görgüç, & Yılmaz, 2020). Specifically, considering their high disposal rates, plant origin by-products can be utilized to obtain bioactive peptides and commercially valuable products (Salami, Luciano, O’Grady, Biondi, Newbold, Kerry, & Priolo, 2019). There have been many studies on the use of plant based bioactive peptides in the development of functional foods, especially in recent years. It has been stated that the bioactive peptides improve the technological properties of food products including processed meats, cheese, bakery products and sauces, such as the water and oil binding capacity, oil emulsification, aroma retention, solubility and gelling properties (Oreopoulou & Tzia, 2007). Bioactive peptides have also been utilized to obtain pharmaceutical components for therapeutic purposes, and for the treatment of chronic diseases such as diabetes and hypertension (Xu, Hong, Wu, & Yan, 2019).

In this regard, presenting a comprehensive review on the topic has become necessary, so this review focuses on the health related properties and techno-functional utilization of bioactive peptides derived from plant origin by-products by interrelating among different studies.