Antioxidant and sensory properties of protein hydrolysate derived from Nile tilapia (Oreochromis niloticus) by one- and two-step hydrolysis

Abstract

Antioxidant and sensory properties of Nile tilapia protein hydrolysates prepared by one- and two-step hydrolysis using commercial proteases were investigated. Hydrolysates prepared using single protease including Alcalase (HA), Flavourzyme (HF), Protamex (HPr) and papain (HPa) had increases in antioxidant activities as the degree of hydrolysis (DH) increased up to 40 % (P < 0.05). Amongst all hydrolysates, HA having 40 % DH showed the highest antioxidant activities. When HA was further hydrolysed by papain, the resulting hydrolysate (HAPa) exhibited the highest antioxidant activities for all assays tested (P < 0.05). ABTS radical scavenging activity and metal chelating of HAPa generally remained constant in a wide pH range (1-11) and during heating at 30-100 °C. Both activities increased in the simulated gastrointestinal tract model system, especially in intestine condition. HAPa (100-1,000 ppm) could retard lipid oxidation in β-carotene-linoleate and lecithin-liposome model systems in a dose dependent manner. Peptides in both HA and HAPa with molecular weight of 513 Da and 1,484 Da possessed the strongest ABTS radical scavenging activity and metal chelating activity, respectively. The amino acid profile of both HA and HAPa contained a high amount of hydrophobic amino acids (38.26-38.85 %) and had glutamic acid/glutamine, lysine and aspartic acid/asparagine as the dominant amino acids. However, HAPa showed a higher acceptability than did HA, owing to the lower bitterness. Therefore, the use of Alcalase in combination with papain for hydrolysis of protein isolate rendered the hydrolysate with antioxidant properties and reduced bitterness, which could serve as the functional supplement.

Antioxidative gelatin hydrolysate from unicorn leatherjacket skin as affected by prior autolysis

“…Fraction containing peptides with MW of 513 Da and 1,484 Da showed the strongest ABTS radical scavenging activity and metal chelating activity, respectively (Yarnpakdee et al 2014). The result suggested that NS-8GE and SS-8GE contained peptides with different sizes and varying modes of action.…”

“…Gelatin hydrolysate from skin of unicorn leatherjacket prepared using autolysis-assisted process with MW of 2,200 Da exhibited higher antioxidative activity than those with MW of 870 Da (Karnjanapratum and Benjakul 2014a). Yarnpakdee et al (2014) Incubation time (h)…”

Preventive effect of Nile tilapia hydrolysate against oxidative damage of HepG2 cells and DNA mediated by H2O2 and AAPH

“…PI from pre-washed mince was prepared following the method of Yarnpakdee et al (2014). Washed mince was homogenised with five volumes of cold distilled water (2-4°C) using an IKA Labortechnik homogeniser (Selangor, Malaysia) at a speed of 11,000 rpm for 1 min.…”

“…Additionally, protein hydrolysates possessing antioxidant activity have been governed by the type of proteases used for step-wise hydrolysis. Recently, the application of Alcalase in combination with papain for hydrolysis of Nile tilapia protein isolate (PI) gave a hydrolysate with antioxidant properties and reduced bitterness (Yarnpakdee et al 2014). Although protein hydrolysates derived from PI have been widely reported to exhibit in vitro antioxidant activity, a little information regarding the antioxidant ability on cell-based models, especially those induced by different types of free radicals, have been reported.…”

Antihypertensive properties of tilapia (Oreochromis spp.) frame and skin enzymatic protein hydrolysates

“…Enzymatic hydrolysates of tilapia muscle containing nearly 40% hydrophobic amino acids [5] showed antioxidant [6] and antihypertensive properties [7]. The preventive effect of tilapia hydrolysate against oxidative damage in HepG2 cells and the protective ability against DNA damage have also been reported [8].…”