Reduction of hexavalent chromium by digested oat bran proteins

Area of Science:

• Biochemistry
• Food Science
• Toxicology

Background:

• Hexavalent chromium (Cr(VI)) exposure increases oxidative stress, damaging DNA, lipids, and proteins.
• Developing effective strategies to counteract Cr(VI) toxicity is crucial for public health.

Purpose of the Study:

• To evaluate the Cr(VI)-reducing and free radical-scavenging capabilities of digested oat bran proteins.
• To explore the potential of food protein hydrolysates as a protective agent against Cr(VI) oxidative damage.

Main Methods:

• Oat bran protein isolates were digested using the endopeptidase Protamex for varying durations (1-4 hours).
• The resulting hydrolysates were analyzed for their ability to reduce Cr(VI) and inhibit superoxide (O2•−) and hydroxyl (HO•) radicals at different pH levels.

Main Results:

• Hydrolysates demonstrated Cr(VI)-reducing activity, with maximums of 5.4% at pH 7.4 and 44.6% at pH 3.0.
• The 2h hydrolysate exhibited the highest O2•− inhibition (57.4%), while the 1h hydrolysate showed the highest HO• inhibition (11.6%).
• A significant correlation (R²=0.82) was found between O2•− scavenging and Cr(VI)-reducing activities at pH 3.0.

Conclusions:

• Digested oat proteins possess significant Cr(VI)-reducing and antioxidant properties.
• The efficacy of these hydrolysates is pH-dependent, suggesting conformational or charge-related mechanisms.
• Further in vivo studies are warranted to confirm the protective effects of these protein hydrolysates against Cr(VI) oxidative stress.