Background Diseases related to oxidative stress and food quality decay are of major concern worldwide as they can lead to economic losses in both public health and food production. The antioxidant peptides, extracted from food proteins, can be explored as natural new drug and food ingredient. Scope and approach Antioxidant peptides are extracted from non-antioxidant precursor proteins from different origin by the activity of either proteolytic microorganisms or isolated enzymes. In the present review, the main sources of bioactive peptides will be discussed. Moreover, the current strategies to obtain these compounds as well as their health benefits and in vivo biological effects will be evaluated. Considerations for further research and development of strategies to increase the knowledge about this underexplored activity of peptides will be also considered. Key findings and conclusions Bioactive peptides' content and profile differ according to the matrix studied and the method used. The utilization of fermentation processes and enzymes has been established to obtain antioxidant bioactive peptides from proteins, being isolated enzymes the most commonly used method, due to their superior control over releasing and obtaining targeted peptides. Antioxidant peptides have the ability to reduce the formation of oxidative products along with the induction of antioxidant enzymes in vivo. However, at this stage of development more in vivo studies are needed in order to evaluate the specific effects on the health of selected antioxidant peptides. In food technology, successful application in meat products strengthens the role of selected peptides as antioxidant additives, although there is a need to observe the effects of the isolated bioactive peptides in other food matrices along with studies to scale-up its production.

/pdf/bioactive-peptides-as-natural-antioxidants-in-food-products-535upiw4kj.pdf

Bioactive peptides as natural antioxidants in food products – A review

Hypertension is an important factor in cardiovascular diseases. Angiotensin-I-converting enzyme (ACE) inhibitors like synthetic drugs are widely used to control hypertension. ACE-inhibitory peptides from food origins could be a good alternative to synthetic drugs. A number of plant-based peptides have been investigated for their potential ACE inhibitor activities by using in vitro and in vivo assays. These plant-based peptides can be obtained by solvent extraction, enzymatic hydrolysis with or without novel food processing methods, and fermentation. ACE-inhibitory activities of peptides can be affected by their structural characteristics such as chain length, composition and sequence. ACE-inhibitory peptides should have gastrointestinal stability and reach the cardiovascular system to show their bioactivity. This paper reviews the current literature on plant-derived ACE-inhibitory peptides including their sources, production and structure, as well as their activity by in vitro and in vivo studies and their bioavailability.

https://www.mdpi.com/2072-6643/9/4/316/pdf

Angiotensin-I-Converting Enzyme (ACE)-Inhibitory Peptides from Plants.

This review presents some of the hottest topics in biotechnological applications: proteases in biocatalysis. Obviously, one of the most relevant areas of application is in the hydrolysis of proteins in food technology, and that has led to a massive use on proteomics. The aim is to identify via peptide maps the different proteins obtained after a specific protease hydrolysis. However, concepts like degradomics are also taking on a more relevant importance in the use and study of proteases and will also be discussed. Other protease applications, as seem in cleaning (detergent development), the pharmaceutical industry, and in fine chemistry, will be analyzed. This review progresses from basic areas such as protease classification to a discussion of the preparation of protease-immobilized biocatalysts, considering the different problems raised by the use of immobilized proteases due to the peculiar features of the substrates, usually large macromolecules. Production of bioactive peptides via limited hydrolysis of proteins will occupy an important place in this review.

/pdf/biotechnological-applications-of-proteases-in-food-3wu7y6o8or.pdf

Biotechnological Applications of Proteases in Food Technology

Mechanisms underlying the effect of polysaccharides in the treatment of type 2 diabetes: A review

https://cyberleninka.org/article/n/703189.pdf

Reactive oxygen species and antioxidant properties from mushrooms

Rice bran protein was hydrolyzed using trypsin. The hydrolysate (RBPH) was then further separated by membrane bioreactor system, gel filtration and reversed phase high-performance liquid chromatography (RP-HPLC). A novel antioxidant and angiotensin I-converting enzyme (ACE) inhibitory peptide named as F2-a, which exhibited high DPPH free radicals scavenging activity, reducing power and ACE inhibitory activity (IC50 of 76 μM) was isolated. The amino acid sequence, Tyr-Ser-Lys (Mw: 395.0 Da), was identified by Quardrupole Time-of-flight Mass Spectrometer (Q-TOF-MS) with an electro-spray ionization (ESI) source. The molecular docking study revealed that the ACE inhibition of Tyr-Ser-Lys was mainly attributed to forming very strong hydrogen bonds with the active pockets of human ACE. These results indicate that rice bran is a potential source of bioactive peptides possessing antioxidant and ACE inhibitory activities.

A novel antioxidant and ACE inhibitory peptide from rice bran protein: Biochemical characterization and molecular docking study

Involvement of the PI3K/Akt signal pathway in the hypoglycemic effects of tea polysaccharides on diabetic mice.

Anti-diabetic effects of Inonotus obliquus polysaccharides in streptozotocin-induced type 2 diabetic mice and potential mechanism via PI3K-Akt signal pathway

Background The rapid increase of drug resistance in conventional antibiotics promotes the discovery and development of antimicrobial peptides (AMPs), which are important components of natural immunity. Due to the specific action modes targeting for cell membrane, AMPs have become a promising substance for bacterium inhibitions barely with no drug resistance. Here we reviewed the structure characteristics related with bactericide actions, including peptides constituents, molecular length, molecular charges and so on. And we also summarized the common mode of actions of AMPs raised by researchers. The structure-mechanism relationship was discussed. The commonly used methods for mechanism study were also listed. Key findings and conclusions The structures of AMPs were strongly related with its efficacy, such as constituents, molecular length, charges, secondary structures. The main mechanisms of AMPs were divided into membrane targets and intracellular targets. Some advanced and new techniques were applied in the mechanism study. Most of the existed mechanisms are still suppositional, and techniques were mainly focused on membrane-associated mechanism, only few of them were related with intracellular factors. Therefore, more new methods are expected to explore the authentic mechanisms and better results as well as more intracellular targets. This review provides a reference for future AMPs chemical modification and mechanism exploration.

Shuqin Li

Papers

A novel antioxidant and ACE inhibitory peptide from rice bran protein: Biochemical characterization and molecular docking study

Involvement of the PI3K/Akt signal pathway in the hypoglycemic effects of tea polysaccharides on diabetic mice.

Anti-diabetic effects of Inonotus obliquus polysaccharides in streptozotocin-induced type 2 diabetic mice and potential mechanism via PI3K-Akt signal pathway

The structure-mechanism relationship and mode of actions of antimicrobial peptides: A review

Preparation and characterization of a novel conformed bipolymer paclitaxel-nanoparticle using tea polysaccharides and zein.