In Vitro Antioxidant Activity and In Vivo Anti-fatigue Effects of Oyster (Ostrea plicatula Gmelin) Peptides Prepared Using Neutral Proteinase

Abstract

The amino acid profile of oyster (Ostrea plicatula Gmelin) peptides (OP) was assayed. Its in vitro antioxidant activity was determined, and its in vivo anti-fatigue activity was compared with those of oyster meat and oyster protein. Seven amino acids that may play an important role in enhancing antioxidant activity account for 25.8% of total OP content. These amino acids are histidine, proline, methionine, cysteine, tyrosine, tryptophan, and phenylalanine. The F-value of OP was 4.89, and the concentration of taurine was 45.43 mmol/mL. OP acted as a scavenger for hydroxyl radicals, 1,1-diphenyl-2-picrylhydrazyl, and superoxide anion radicals. It also inhibited lipid peroxidation. The intragastric administration of OP prolonged the swimming time to exhaustion of mice by 78% over that of the control. It decreased the levels of serum lactic acid and blood urea nitrogen by 24.8% and 11.2%, respectively. Finally, it increased the levels of liver glycogen (1.0-fold) and gastrocnemius muscle glycogen (55.6%).Keywords: oyster peptides, antioxidant activity, anti-fatigue effect, endurance exercise *To whom correspondence should be addressed. E-mail: zhangch2@139.com IntroductionAcute and/or chronic exercises are associated with increases in free radicals and ROS production, which are due primarily to the increase in oxygen uptake by active tissues (Ji, 1995;Powers and Jackson, 2008). The imbalance between free radical/ROS production and its removal by antioxidant defense systems causes oxidative stress (Chalamaiah et al., 2012). Oxidative stress may lead to potential damage and consequently diminish athletic performance. Thus, increased free radical/ROS production has been associated with altered muscle function and elevated rates of muscle fatigue (Deaton and Marlin, 2003).Research consensus reflects support for the idea that antioxidative peptides can reduce the damage induced by ROS and free radicals. The antioxidative peptides from aquatic products have become of recent concern because they are considered safe and healthy molecules with low molecular weight, easy absorption, low cost, and high activity (Sarmadi and Ismail, 2010). The precursor protein in these peptides is mostly inactive. These active peptides can also be released from the precursor protein by hydrolysis techniques, such as enzymatic hydrolysis, autolytic process using endogenous enzymes, and microbial fermentation (Chalamaiah et al., 2012;Je et al., 2007;Rajapakse et al., 2005;Kim et al., 2007).In this study, we assayed the amino acid profile of oyster peptides (OP), and then investigated its in vitro antioxidant activities and the in vivo anti-fatigue effects of OP previously prepared by neutral proteinase digestion. The in vitro antioxidant activities were studied by determining the activities of hydroxyl radicals, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and superoxide anion radical scavengers, as well as lipid peroxidation inhibitory activity in a linoleic acid emulsion system. In the determination, glutathione (GSH) which is a well known peptide an...

Anti‐fatigue activity of sea cucumber peptides prepared from Stichopus japonicus in an endurance swimming rat model

“…It has been found that peptides containing glutamic acid or glutamic acid have high activity of scavenging free radical . Several amino acids, such as tyrosine, proline, methionine, lysine, histidine and tryptophan, can enhance the antioxidant activities of peptides . The total content of the seven amino acids mentioned above in SCP was 34%, indicating SCP might have latent antioxidant activity.…”

“…31 Several amino acids, such as tyrosine, proline, methionine, lysine, histidine and tryptophan, can enhance the antioxidant activities of peptides. 32,33 The total content of the seven amino acids mentioned above in SCP was 34%, indicating SCP might have latent antioxidant activity. Some amino acids are thought to be associated with the regulatory metabolism involved in muscular activity; they can improve exercise capability and remarkably slow down the catabolism of proteins in the muscle during exercise.…”

A comprehensive review of oyster peptides: Preparation, characterisation and bioactivities

“…Moreover, OPs can increase muscle and liver glycogen levels, as well as supplement glycogen replenishment during strenuous exercise. 134 Moreover, OPs have been found to significantly reduce serum levels of lactic acid and blood urea nitrogen (BUN), both indicators used in in vitro evaluation of anti-fatigue drugs and human endurance. 13,135 Oyster peptides also possess demonstrated anticoagulant and antithrombotic properties.…”

Hypoxia Tolerance and Fatigue Relief Produced by <i>Lepidium meyenii</i> and its Water-soluble Polysaccharide in Mice

“…An increase in LDH would accelerate the glycolysis process, producing more energy as well as blood lactic acid (BLA). Lactic acid may cause fatigue according to Hill and Kupalov's research (Hill, et al, 1929), so it is also often detected as an indicator in anti-fatigue tests (Hao, Cao, Hao and Zhang, 2013;Xu, Lv, Lo, Cui, Hu and Fan, 2012).…”

“…An increase in LDH would accelerate the glycolysis process, producing more energy as well as blood lactic acid (BLA). Lactic acid may cause fatigue according to Hill and Kupalov's research (Hill, et al, 1929), so it is also often detected as an indicator in anti-fatigue tests (Hao, Cao, Hao and Zhang, 2013;Xu, Lv, Lo, Cui, Hu and Fan, 2012).Glycogen, including liver glycogen (LG) and muscle glycogen (MG), is an important energy source stored in the body. Glycogen could be used to complement the consumption of blood sugar (Ren, Zhao, Wang, Cui and You, 2011;Shao, Wang and Zheng, 2013).…”