Boletus edulis Nitrite Reductase Reduces Nitrite Content of Pickles and Mitigates Intoxication in Nitrite-intoxicated Mice

Abstract

Pickles are popular in China and exhibits health-promoting effects. However, nitrite produced during fermentation adversely affects health due to formation of methemoglobin and conversion to carcinogenic nitrosamine. Fruiting bodies of the mushroom Boletus edulis were capable of inhibiting nitrite production during pickle fermentation. A 90-kDa nitrite reductase (NiR), demonstrating peptide sequence homology to fungal nitrite reductase, was isolated from B. edulis fruiting bodies. The optimum temperature and pH of the enzyme was 45 °C and 6.8, respectively. B. edulis NiR was capable of prolonging the lifespan of nitrite-intoxicated mice, indicating that it had the action of an antidote. The enzyme could also eliminate nitrite from blood after intragastric administration of sodium nitrite, and after packaging into capsule, this nitrite-eliminating activity could persist for at least 120 minutes thus avoiding immediate gastric degradation. B. edulis NiR represents the first nitrite reductase purified from mushrooms and may facilitate subsequent applications.

Production of Pork Sausages Using Pleaurotus eryngii with Different Treatments as Replacements for Pork Back Fat

“…Similarly, Zhang et al. () found that nitrite reductase in Boletus edulis reduced the nitrite content of pickles and mitigated intoxication of nitrite‐intoxicated mice. Moreover, no statistical significant difference ( P > 0.05) was observed between the control and P2, suggesting that the functional components in P. eryngii might disappear with an increasing temperature.…”

Uncured-Labeled Meat Products Produced Using Plant-Derived Nitrates and Nitrites: Chemistry, Safety, and Regulatory Considerations

“…Efforts to abate nitrate and nitrite exposure in foodstuffs have extended to products beyond cured meats. Agronomy implementations have resulted in the successful cultivation of nitrate-free lettuce and nitrite levels in pickles have been reduced by 97% with the inclusion of nitrite reductase-generating mushrooms ( Boletus edulis ). , With a seemingly boundless demand for nitrate and nitrite-free products, it is likely the marketplace will continue to observe an expansion of clean-label, nitrate and nitrite-free alternatives.…”

Fermented Vegetables: Health Benefits, Defects, and Current Technological Solutions

“…There are also identical sequences of microbial nitrite reductase in other foods. For instance, mushroom-isolated nitrite reductase with a molecular weight of 90 kDa is homologous to the peptide sequence of fungi-derived nitrite reductase [ 137 ]. Consequently, some natural foods containing nitrite reductase have the potential to be used to produce fermented vegetables to reduce nitrite content.…”