The study has applied multiple-enzyme hydrolysis to prepare jellyfish peptides with lower molecular weights. The authors from the Chinese Academy of Sciences, Shandong, China, state: “This method not only has a higher protein utilisation rate but also produces a product that is more easily absorbed by the human body.”
The authors of the new study also referenced that synthesised antioxidants can have detrimental effects, and suggest that jellyfish derived peptides could offer safer alternatives. They state: “Unlike chemically synthesised antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and tert-Butylhydroquinone (TBHQ), which have been linked to adverse health effects, jellyfish peptides exhibit favourable and secure biological activity.
“To mitigate this issue, the search for natural sources of safe antioxidants as substitutes for synthetic antioxidants is gaining more attention.”
The authors of the study report that their abundant population due to climate change, ease of acquisition, and high protein content, present jellyfish as a readily available, sustainable and unique source of bioactive substances.
The report states: “Jellyfish produce bioactive peptides more efficiently and simply than other cnidarians, and because they are plentiful in oceans, they are easy to harvest.
“Research and development on jellyfish bioactive compounds has the potential to make significant advancements in a variety of fields, including agriculture, medicine, and the food industry.”
Previous studies have shown that, compared with proteins, bioactive peptides have an increased variety of biological activities. The authors of the new study state: “Peptides with lower molecular weights are easier to absorb through the intestinal barrier to carry out their biological functions. The final peptide product's activity is significantly influenced by the preparation process.”
Predominantly, collagen and collagen peptides are the main topics of research on the protein resources in jellyfish. In previous studies, these substances have shown a wide range of biological activities, including potential as a new biological material, immune stimulation, nutritional skin care, antioxidant properties, and antihypertensive effects.
However, the authors report that the common extraction procedure is challenging and results in protein waste, and that most studies investigate peptides with molecular weight higher than 1000 Da (meaning Dalton, a measure of molecular weight). This is due to hydrolysis with a single enzyme, which the authors suggest could neglect the benefits of peptides with smaller molecular weights.
This new study applied multiple-enzyme hydrolysis to prepare jellyfish peptides with lower molecular weights. The authors report: “The antioxidant activity of JPHT-2 in this study was significantly improved after multi-enzyme hydrolysis."
Additionally, the study involved tests to determine the antioxidant activity of jellyfish peptides and to explore their potential as an alternative source of antioxidants. The study concludes: “It is a significant advantage of jellyfish peptides that they offer an alternative to synthesised antioxidants and can be utilised in a variety of applications.”
In the study, the salted jellyfish, Nemopilema nomurai, was subjected to a soaking process with constant water changes every four hours for four days to eliminate excess salt.
Following this, jellyfish peptides (JPHT-2) were obtained through enzymatic hydrolysis of lyophilised (freeze-dried) jellyfish powder under optimal conditions. Enzymatic hydrolysis utilises proteases to destroy the spatial structure of proteins and amide bonds to obtain polypeptides or oligopeptides with different molecular weights, activities, and amino acid compositions.
The radical scavenging ability of JPHT-2 was evaluated by adding 1 ml of JPHT-2 solution to 1ml of phosphate buffer solution, incubating the reaction mixture at 37 °C for 5 minutes, and measuring absorbance using a universal microplate reader.
When measuring antioxidant activity, findings indicated that JPHT-2 possesses significant radical-scavenging activity and reducing power.
The authors report: “JPHT-2 exhibited a remarkable ability to scavenge hydroxyl radicals, with a rate of up to 50%.”
Additionally, at a cellular level, JPHT-2 was able to protect HaCaT cells (an immortalised human keratinocyte line commonly utilised in in vitro studies), from H2O2-induced oxidative damage by increasing the level of superoxide dismutase (SOD), the important antioxidant defence against oxidative stress, in cells.
The study concludes low-molecular-weight jellyfish peptides are easily produced through hydrolysis and demonstrate exceptional antioxidant activity and safety.
The authors state: “The results not only provide a reference for the application of jellyfish peptides in preventing various degenerative diseases related to oxidative damage, but also provide a theoretical basis for the utilisation of jellyfish resources.”
The authors recognise that limitations exist in this study, recognising that while there is potential for jellyfish as an antioxidant resource, “it’s antioxidant mechanism, structure, and amino acid sequence are unknown. Future studies are needed to reveal the relationship between structure and activity.”
“Jellyfish Peptide as an Alternative Source of Antioxidant”