Loop-mediated isothermal amplification (LAMP) for rapid and easy identification of Omphalotus japonicus

Yohei Sugano; Kozue Sakata; Kosuke Nakamura; Aoi Hosokawa; Hirokazu Kouguchi; Tomohiro Suzuki; Kazunari Kondo

doi:10.1016/j.fochms.2022.100115

Loop-mediated isothermal amplification (LAMP) for rapid and easy identification of Omphalotus japonicus

Food Chem (Oxf). 2022 Jun 18:5:100115. doi: 10.1016/j.fochms.2022.100115. eCollection 2022 Dec 30.

Authors

Yohei Sugano¹, Kozue Sakata², Kosuke Nakamura³, Aoi Hosokawa¹, Hirokazu Kouguchi⁴, Tomohiro Suzuki⁵, Kazunari Kondo²

Affiliations

¹ Department of Food Hygiene, Hokkaido Institute of Public Health, Kita-ku, 0600819 Sapporo, Japan.
² Division of Biochemistry, National Institute of Health Sciences, Kawasaki-ku, 2109501 Kawasaki, Japan.
³ Division of Foods, National Institute of Health Sciences, Kawasaki-ku, 2109501 Kawasaki, Japan.
⁴ Department of Infectious Diseases, Hokkaido Institute of Public Health, Kita-ku, 0600819 Sapporo, Japan.
⁵ Department of General Affairs and Planning, Hokkaido Institute of Public Health, Kita-ku, 0600819 Sapporo, Japan.

Abstract

Omphalotus japonicus is a major toxic mushroom in Japan. When food poisoning caused by O. japonicus occurs, quick and accurate identification using a method that does not rely on morphological discrimination is required. Because the loop-mediated isothermal amplification (LAMP) method meets these requirements, we developed a LAMP method for detecting O. japonicus. Amplification occurred within 60 min, and the presence or absence of O. japonicus was confirmed within 2 h, including the DNA extraction protocol. The LAMP method did not show cross-reactivity with 13 species of edible mushrooms, had high specificity toward O. japonicus, and had sufficient detection sensitivity even in a mixed mushroom sample containing 1% O. japonicus. Additionally, O. japonicus could be detected in simulated food poisoning samples of heated and digested mushrooms, and in actual food poisoning residual samples.

Keywords: Food poisoning; Genetic identification; Loop-mediated isothermal amplification; Omphalotus japonicus; Toxic mushroom.