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

Weiwei Zhang; Guoting Tian; Shanshan Feng; Jack Ho Wong; Yongchang Zhao; Xiao Chen; Hexiang Wang; Tzi Bun Ng

doi:10.1038/srep14907

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

Sci Rep. 2015 Oct 8:5:14907. doi: 10.1038/srep14907.

Authors

Weiwei Zhang¹, Guoting Tian², Shanshan Feng¹, Jack Ho Wong², Yongchang Zhao², Xiao Chen¹, Hexiang Wang¹, Tzi Bun Ng³

Affiliations

¹ State Key Laboratory for Agrobiotechnology and Department of Microbiology, China Agricultural University, Beijing 100193, China.
² Institute of Biotechnology and Germplasmic Resource, Yunnan Academy of Agricultural Science, Kunming 650223, P.R. China.
³ School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.

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.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Agaricales / chemistry*
Agaricales / enzymology
Animals
Antidotes / isolation & purification
Antidotes / metabolism
Antidotes / pharmacokinetics
Antidotes / pharmacology*
Carcinogens / antagonists & inhibitors
Carcinogens / metabolism
Diet
Enzyme Assays
Fermentation / drug effects
Fruiting Bodies, Fungal / chemistry
Fruiting Bodies, Fungal / enzymology
Fungal Proteins / isolation & purification
Fungal Proteins / metabolism
Fungal Proteins / pharmacokinetics
Fungal Proteins / pharmacology*
Humans
Hydrogen-Ion Concentration
Kinetics
Male
Methemoglobin / antagonists & inhibitors
Methemoglobin / metabolism
Mice
Nitrite Reductases / isolation & purification
Nitrite Reductases / metabolism
Nitrite Reductases / pharmacokinetics
Nitrite Reductases / pharmacology*
Nitrosamines / antagonists & inhibitors
Nitrosamines / metabolism
Rats, Sprague-Dawley
Sodium Nitrite / metabolism
Sodium Nitrite / poisoning*
Temperature
Vegetables / poisoning

Substances

Antidotes
Carcinogens
Fungal Proteins
Nitrosamines
Methemoglobin
Nitrite Reductases
Sodium Nitrite